OpenCloudOS-Kernel/drivers/iio/adc/meson_saradc.c

1496 lines
45 KiB
C
Raw Normal View History

// SPDX-License-Identifier: GPL-2.0
iio: adc: add a driver for the SAR ADC found in Amlogic Meson SoCs This adds support for the SAR (Successive Approximation Register) ADC on the Amlogic Meson SoCs. The code is based on the public S805 (Meson8b) and S905 (GXBB) datasheets (see [0] and [1]), as well as by reading (various versions of) the vendor driver and by inspecting the registers on the vendor kernels of my testing-hardware. Currently the GXBB, GXL and GXM SoCs are supported. GXBB hardware has 10-bit ADC resolution, while GXL and GXM have 12-bit ADC resolution. The code was written to support older SoCs (Meson8 and Meson8b) as well, but due to lack of actual testing-hardware no of_device_id was added for these. Two "features" from the vendor driver are currently missing: - the vendor driver uses channel #7 for calibration (this improves the accuracy of the results - in my tests the results were less than 3% off without calibration compared to the vendor driver). Adding support for this should be easy, but is not required for most applications. - channel #6 is connected to the SoCs internal temperature sensor. Adding support for this is probably not so easy since (based on the u-boot sources) most SoC versions are using different registers and algorithms for the conversion from "ADC value" to temperature. Supported by the hardware but currently not supported by the driver: - reading multiple channels at the same time (the hardware has a FIFO buffer which stores multiple results) - continuous sampling (this would require a way to enable this individually because otherwise the ADC would be drawing power constantly) - interrupt support (similar to the vendor driver this new driver is polling the results. It is unclear if the IRQ-mode is supported on older (Meson6 or Meson8) hardware as well or if there are any errata) [0] http://dn.odroid.com/S805/Datasheet/S805_Datasheet%20V0.8%2020150126.pdf [1] http://dn.odroid.com/S905/DataSheet/S905_Public_Datasheet_V1.1.4.pdf Signed-off-by: Martin Blumenstingl <martin.blumenstingl@googlemail.com> Tested-by: Neil Armstrong <narmstrong@baylibre.com> Signed-off-by: Jonathan Cameron <jic23@kernel.org>
2017-01-23 02:17:13 +08:00
/*
* Amlogic Meson Successive Approximation Register (SAR) A/D Converter
*
* Copyright (C) 2017 Martin Blumenstingl <martin.blumenstingl@googlemail.com>
*/
#include <linux/bitfield.h>
#include <linux/clk.h>
#include <linux/clk-provider.h>
#include <linux/delay.h>
#include <linux/io.h>
#include <linux/iio/iio.h>
#include <linux/module.h>
#include <linux/mutex.h>
iio: adc: meson-saradc: add support for the chip's temperature sensor Channel 6 of the SAR ADC can be switched between two inputs: SAR_ADC_CH6 input (an actual pad on the SoC) and the signal from the temperature sensor inside the SoC. To get usable results from the temperature sensor we need to read the corresponding calibration data from the eFuse and pass it to the SAR ADC registers. If the temperature sensor is not calibrated (the eFuse data contains a bit for this) then the driver will only register the iio_chan_spec's for voltage measurements. This only enables the temperature sensor for the Meson8 SoC. Meson8b and Meson8m2 SoCs can be supported in the future as well but we first need a way to pass the fifth TSC (temperature sensor coefficient) bit to the HHI register area (apart from that the infrastructure as already implemented for Meson8 can be used). On the 64-bit SoCs (GXBB, GXL and GXM) the temperature sensor inside SAR ADC is firmware-controlled (by BL30, we can simply use the SCPI hwmon driver to get the chip temperature). To keep the devicetree interface backwards compatible we simply skip the temperature sensor initialization if no eFuse nvmem cell is passed via devicetree. The public documentation for the SAR ADC IP block does not explain how to use the registers to read the temperature. The logic from this patch is based on reading and understanding Amlogic's GPL kernel sources. Signed-off-by: Martin Blumenstingl <martin.blumenstingl@googlemail.com> Signed-off-by: Jonathan Cameron <Jonathan.Cameron@huawei.com>
2018-11-04 07:10:24 +08:00
#include <linux/nvmem-consumer.h>
#include <linux/interrupt.h>
iio: adc: add a driver for the SAR ADC found in Amlogic Meson SoCs This adds support for the SAR (Successive Approximation Register) ADC on the Amlogic Meson SoCs. The code is based on the public S805 (Meson8b) and S905 (GXBB) datasheets (see [0] and [1]), as well as by reading (various versions of) the vendor driver and by inspecting the registers on the vendor kernels of my testing-hardware. Currently the GXBB, GXL and GXM SoCs are supported. GXBB hardware has 10-bit ADC resolution, while GXL and GXM have 12-bit ADC resolution. The code was written to support older SoCs (Meson8 and Meson8b) as well, but due to lack of actual testing-hardware no of_device_id was added for these. Two "features" from the vendor driver are currently missing: - the vendor driver uses channel #7 for calibration (this improves the accuracy of the results - in my tests the results were less than 3% off without calibration compared to the vendor driver). Adding support for this should be easy, but is not required for most applications. - channel #6 is connected to the SoCs internal temperature sensor. Adding support for this is probably not so easy since (based on the u-boot sources) most SoC versions are using different registers and algorithms for the conversion from "ADC value" to temperature. Supported by the hardware but currently not supported by the driver: - reading multiple channels at the same time (the hardware has a FIFO buffer which stores multiple results) - continuous sampling (this would require a way to enable this individually because otherwise the ADC would be drawing power constantly) - interrupt support (similar to the vendor driver this new driver is polling the results. It is unclear if the IRQ-mode is supported on older (Meson6 or Meson8) hardware as well or if there are any errata) [0] http://dn.odroid.com/S805/Datasheet/S805_Datasheet%20V0.8%2020150126.pdf [1] http://dn.odroid.com/S905/DataSheet/S905_Public_Datasheet_V1.1.4.pdf Signed-off-by: Martin Blumenstingl <martin.blumenstingl@googlemail.com> Tested-by: Neil Armstrong <narmstrong@baylibre.com> Signed-off-by: Jonathan Cameron <jic23@kernel.org>
2017-01-23 02:17:13 +08:00
#include <linux/of.h>
#include <linux/of_irq.h>
iio: adc: add a driver for the SAR ADC found in Amlogic Meson SoCs This adds support for the SAR (Successive Approximation Register) ADC on the Amlogic Meson SoCs. The code is based on the public S805 (Meson8b) and S905 (GXBB) datasheets (see [0] and [1]), as well as by reading (various versions of) the vendor driver and by inspecting the registers on the vendor kernels of my testing-hardware. Currently the GXBB, GXL and GXM SoCs are supported. GXBB hardware has 10-bit ADC resolution, while GXL and GXM have 12-bit ADC resolution. The code was written to support older SoCs (Meson8 and Meson8b) as well, but due to lack of actual testing-hardware no of_device_id was added for these. Two "features" from the vendor driver are currently missing: - the vendor driver uses channel #7 for calibration (this improves the accuracy of the results - in my tests the results were less than 3% off without calibration compared to the vendor driver). Adding support for this should be easy, but is not required for most applications. - channel #6 is connected to the SoCs internal temperature sensor. Adding support for this is probably not so easy since (based on the u-boot sources) most SoC versions are using different registers and algorithms for the conversion from "ADC value" to temperature. Supported by the hardware but currently not supported by the driver: - reading multiple channels at the same time (the hardware has a FIFO buffer which stores multiple results) - continuous sampling (this would require a way to enable this individually because otherwise the ADC would be drawing power constantly) - interrupt support (similar to the vendor driver this new driver is polling the results. It is unclear if the IRQ-mode is supported on older (Meson6 or Meson8) hardware as well or if there are any errata) [0] http://dn.odroid.com/S805/Datasheet/S805_Datasheet%20V0.8%2020150126.pdf [1] http://dn.odroid.com/S905/DataSheet/S905_Public_Datasheet_V1.1.4.pdf Signed-off-by: Martin Blumenstingl <martin.blumenstingl@googlemail.com> Tested-by: Neil Armstrong <narmstrong@baylibre.com> Signed-off-by: Jonathan Cameron <jic23@kernel.org>
2017-01-23 02:17:13 +08:00
#include <linux/platform_device.h>
#include <linux/regmap.h>
#include <linux/regulator/consumer.h>
#include <linux/mfd/syscon.h>
iio: adc: add a driver for the SAR ADC found in Amlogic Meson SoCs This adds support for the SAR (Successive Approximation Register) ADC on the Amlogic Meson SoCs. The code is based on the public S805 (Meson8b) and S905 (GXBB) datasheets (see [0] and [1]), as well as by reading (various versions of) the vendor driver and by inspecting the registers on the vendor kernels of my testing-hardware. Currently the GXBB, GXL and GXM SoCs are supported. GXBB hardware has 10-bit ADC resolution, while GXL and GXM have 12-bit ADC resolution. The code was written to support older SoCs (Meson8 and Meson8b) as well, but due to lack of actual testing-hardware no of_device_id was added for these. Two "features" from the vendor driver are currently missing: - the vendor driver uses channel #7 for calibration (this improves the accuracy of the results - in my tests the results were less than 3% off without calibration compared to the vendor driver). Adding support for this should be easy, but is not required for most applications. - channel #6 is connected to the SoCs internal temperature sensor. Adding support for this is probably not so easy since (based on the u-boot sources) most SoC versions are using different registers and algorithms for the conversion from "ADC value" to temperature. Supported by the hardware but currently not supported by the driver: - reading multiple channels at the same time (the hardware has a FIFO buffer which stores multiple results) - continuous sampling (this would require a way to enable this individually because otherwise the ADC would be drawing power constantly) - interrupt support (similar to the vendor driver this new driver is polling the results. It is unclear if the IRQ-mode is supported on older (Meson6 or Meson8) hardware as well or if there are any errata) [0] http://dn.odroid.com/S805/Datasheet/S805_Datasheet%20V0.8%2020150126.pdf [1] http://dn.odroid.com/S905/DataSheet/S905_Public_Datasheet_V1.1.4.pdf Signed-off-by: Martin Blumenstingl <martin.blumenstingl@googlemail.com> Tested-by: Neil Armstrong <narmstrong@baylibre.com> Signed-off-by: Jonathan Cameron <jic23@kernel.org>
2017-01-23 02:17:13 +08:00
#define MESON_SAR_ADC_REG0 0x00
#define MESON_SAR_ADC_REG0_PANEL_DETECT BIT(31)
#define MESON_SAR_ADC_REG0_BUSY_MASK GENMASK(30, 28)
#define MESON_SAR_ADC_REG0_DELTA_BUSY BIT(30)
#define MESON_SAR_ADC_REG0_AVG_BUSY BIT(29)
#define MESON_SAR_ADC_REG0_SAMPLE_BUSY BIT(28)
#define MESON_SAR_ADC_REG0_FIFO_FULL BIT(27)
#define MESON_SAR_ADC_REG0_FIFO_EMPTY BIT(26)
#define MESON_SAR_ADC_REG0_FIFO_COUNT_MASK GENMASK(25, 21)
#define MESON_SAR_ADC_REG0_ADC_BIAS_CTRL_MASK GENMASK(20, 19)
#define MESON_SAR_ADC_REG0_CURR_CHAN_ID_MASK GENMASK(18, 16)
#define MESON_SAR_ADC_REG0_ADC_TEMP_SEN_SEL BIT(15)
#define MESON_SAR_ADC_REG0_SAMPLING_STOP BIT(14)
#define MESON_SAR_ADC_REG0_CHAN_DELTA_EN_MASK GENMASK(13, 12)
#define MESON_SAR_ADC_REG0_DETECT_IRQ_POL BIT(10)
#define MESON_SAR_ADC_REG0_DETECT_IRQ_EN BIT(9)
#define MESON_SAR_ADC_REG0_FIFO_CNT_IRQ_MASK GENMASK(8, 4)
#define MESON_SAR_ADC_REG0_FIFO_IRQ_EN BIT(3)
#define MESON_SAR_ADC_REG0_SAMPLING_START BIT(2)
#define MESON_SAR_ADC_REG0_CONTINUOUS_EN BIT(1)
#define MESON_SAR_ADC_REG0_SAMPLE_ENGINE_ENABLE BIT(0)
#define MESON_SAR_ADC_CHAN_LIST 0x04
#define MESON_SAR_ADC_CHAN_LIST_MAX_INDEX_MASK GENMASK(26, 24)
#define MESON_SAR_ADC_CHAN_LIST_ENTRY_MASK(_chan) \
(GENMASK(2, 0) << ((_chan) * 3))
#define MESON_SAR_ADC_AVG_CNTL 0x08
#define MESON_SAR_ADC_AVG_CNTL_AVG_MODE_SHIFT(_chan) \
(16 + ((_chan) * 2))
#define MESON_SAR_ADC_AVG_CNTL_AVG_MODE_MASK(_chan) \
(GENMASK(17, 16) << ((_chan) * 2))
#define MESON_SAR_ADC_AVG_CNTL_NUM_SAMPLES_SHIFT(_chan) \
(0 + ((_chan) * 2))
#define MESON_SAR_ADC_AVG_CNTL_NUM_SAMPLES_MASK(_chan) \
(GENMASK(1, 0) << ((_chan) * 2))
#define MESON_SAR_ADC_REG3 0x0c
#define MESON_SAR_ADC_REG3_CNTL_USE_SC_DLY BIT(31)
#define MESON_SAR_ADC_REG3_CLK_EN BIT(30)
#define MESON_SAR_ADC_REG3_BL30_INITIALIZED BIT(28)
#define MESON_SAR_ADC_REG3_CTRL_CONT_RING_COUNTER_EN BIT(27)
#define MESON_SAR_ADC_REG3_CTRL_SAMPLING_CLOCK_PHASE BIT(26)
#define MESON_SAR_ADC_REG3_CTRL_CHAN7_MUX_SEL_MASK GENMASK(25, 23)
#define MESON_SAR_ADC_REG3_DETECT_EN BIT(22)
#define MESON_SAR_ADC_REG3_ADC_EN BIT(21)
#define MESON_SAR_ADC_REG3_PANEL_DETECT_COUNT_MASK GENMASK(20, 18)
#define MESON_SAR_ADC_REG3_PANEL_DETECT_FILTER_TB_MASK GENMASK(17, 16)
#define MESON_SAR_ADC_REG3_ADC_CLK_DIV_SHIFT 10
#define MESON_SAR_ADC_REG3_ADC_CLK_DIV_WIDTH 6
iio: adc: add a driver for the SAR ADC found in Amlogic Meson SoCs This adds support for the SAR (Successive Approximation Register) ADC on the Amlogic Meson SoCs. The code is based on the public S805 (Meson8b) and S905 (GXBB) datasheets (see [0] and [1]), as well as by reading (various versions of) the vendor driver and by inspecting the registers on the vendor kernels of my testing-hardware. Currently the GXBB, GXL and GXM SoCs are supported. GXBB hardware has 10-bit ADC resolution, while GXL and GXM have 12-bit ADC resolution. The code was written to support older SoCs (Meson8 and Meson8b) as well, but due to lack of actual testing-hardware no of_device_id was added for these. Two "features" from the vendor driver are currently missing: - the vendor driver uses channel #7 for calibration (this improves the accuracy of the results - in my tests the results were less than 3% off without calibration compared to the vendor driver). Adding support for this should be easy, but is not required for most applications. - channel #6 is connected to the SoCs internal temperature sensor. Adding support for this is probably not so easy since (based on the u-boot sources) most SoC versions are using different registers and algorithms for the conversion from "ADC value" to temperature. Supported by the hardware but currently not supported by the driver: - reading multiple channels at the same time (the hardware has a FIFO buffer which stores multiple results) - continuous sampling (this would require a way to enable this individually because otherwise the ADC would be drawing power constantly) - interrupt support (similar to the vendor driver this new driver is polling the results. It is unclear if the IRQ-mode is supported on older (Meson6 or Meson8) hardware as well or if there are any errata) [0] http://dn.odroid.com/S805/Datasheet/S805_Datasheet%20V0.8%2020150126.pdf [1] http://dn.odroid.com/S905/DataSheet/S905_Public_Datasheet_V1.1.4.pdf Signed-off-by: Martin Blumenstingl <martin.blumenstingl@googlemail.com> Tested-by: Neil Armstrong <narmstrong@baylibre.com> Signed-off-by: Jonathan Cameron <jic23@kernel.org>
2017-01-23 02:17:13 +08:00
#define MESON_SAR_ADC_REG3_BLOCK_DLY_SEL_MASK GENMASK(9, 8)
#define MESON_SAR_ADC_REG3_BLOCK_DLY_MASK GENMASK(7, 0)
#define MESON_SAR_ADC_DELAY 0x10
#define MESON_SAR_ADC_DELAY_INPUT_DLY_SEL_MASK GENMASK(25, 24)
#define MESON_SAR_ADC_DELAY_BL30_BUSY BIT(15)
#define MESON_SAR_ADC_DELAY_KERNEL_BUSY BIT(14)
#define MESON_SAR_ADC_DELAY_INPUT_DLY_CNT_MASK GENMASK(23, 16)
#define MESON_SAR_ADC_DELAY_SAMPLE_DLY_SEL_MASK GENMASK(9, 8)
#define MESON_SAR_ADC_DELAY_SAMPLE_DLY_CNT_MASK GENMASK(7, 0)
#define MESON_SAR_ADC_LAST_RD 0x14
#define MESON_SAR_ADC_LAST_RD_LAST_CHANNEL1_MASK GENMASK(23, 16)
#define MESON_SAR_ADC_LAST_RD_LAST_CHANNEL0_MASK GENMASK(9, 0)
#define MESON_SAR_ADC_FIFO_RD 0x18
#define MESON_SAR_ADC_FIFO_RD_CHAN_ID_MASK GENMASK(14, 12)
#define MESON_SAR_ADC_FIFO_RD_SAMPLE_VALUE_MASK GENMASK(11, 0)
#define MESON_SAR_ADC_AUX_SW 0x1c
#define MESON_SAR_ADC_AUX_SW_MUX_SEL_CHAN_SHIFT(_chan) \
(8 + (((_chan) - 2) * 3))
iio: adc: add a driver for the SAR ADC found in Amlogic Meson SoCs This adds support for the SAR (Successive Approximation Register) ADC on the Amlogic Meson SoCs. The code is based on the public S805 (Meson8b) and S905 (GXBB) datasheets (see [0] and [1]), as well as by reading (various versions of) the vendor driver and by inspecting the registers on the vendor kernels of my testing-hardware. Currently the GXBB, GXL and GXM SoCs are supported. GXBB hardware has 10-bit ADC resolution, while GXL and GXM have 12-bit ADC resolution. The code was written to support older SoCs (Meson8 and Meson8b) as well, but due to lack of actual testing-hardware no of_device_id was added for these. Two "features" from the vendor driver are currently missing: - the vendor driver uses channel #7 for calibration (this improves the accuracy of the results - in my tests the results were less than 3% off without calibration compared to the vendor driver). Adding support for this should be easy, but is not required for most applications. - channel #6 is connected to the SoCs internal temperature sensor. Adding support for this is probably not so easy since (based on the u-boot sources) most SoC versions are using different registers and algorithms for the conversion from "ADC value" to temperature. Supported by the hardware but currently not supported by the driver: - reading multiple channels at the same time (the hardware has a FIFO buffer which stores multiple results) - continuous sampling (this would require a way to enable this individually because otherwise the ADC would be drawing power constantly) - interrupt support (similar to the vendor driver this new driver is polling the results. It is unclear if the IRQ-mode is supported on older (Meson6 or Meson8) hardware as well or if there are any errata) [0] http://dn.odroid.com/S805/Datasheet/S805_Datasheet%20V0.8%2020150126.pdf [1] http://dn.odroid.com/S905/DataSheet/S905_Public_Datasheet_V1.1.4.pdf Signed-off-by: Martin Blumenstingl <martin.blumenstingl@googlemail.com> Tested-by: Neil Armstrong <narmstrong@baylibre.com> Signed-off-by: Jonathan Cameron <jic23@kernel.org>
2017-01-23 02:17:13 +08:00
#define MESON_SAR_ADC_AUX_SW_VREF_P_MUX BIT(6)
#define MESON_SAR_ADC_AUX_SW_VREF_N_MUX BIT(5)
#define MESON_SAR_ADC_AUX_SW_MODE_SEL BIT(4)
#define MESON_SAR_ADC_AUX_SW_YP_DRIVE_SW BIT(3)
#define MESON_SAR_ADC_AUX_SW_XP_DRIVE_SW BIT(2)
#define MESON_SAR_ADC_AUX_SW_YM_DRIVE_SW BIT(1)
#define MESON_SAR_ADC_AUX_SW_XM_DRIVE_SW BIT(0)
#define MESON_SAR_ADC_CHAN_10_SW 0x20
#define MESON_SAR_ADC_CHAN_10_SW_CHAN1_MUX_SEL_MASK GENMASK(25, 23)
#define MESON_SAR_ADC_CHAN_10_SW_CHAN1_VREF_P_MUX BIT(22)
#define MESON_SAR_ADC_CHAN_10_SW_CHAN1_VREF_N_MUX BIT(21)
#define MESON_SAR_ADC_CHAN_10_SW_CHAN1_MODE_SEL BIT(20)
#define MESON_SAR_ADC_CHAN_10_SW_CHAN1_YP_DRIVE_SW BIT(19)
#define MESON_SAR_ADC_CHAN_10_SW_CHAN1_XP_DRIVE_SW BIT(18)
#define MESON_SAR_ADC_CHAN_10_SW_CHAN1_YM_DRIVE_SW BIT(17)
#define MESON_SAR_ADC_CHAN_10_SW_CHAN1_XM_DRIVE_SW BIT(16)
#define MESON_SAR_ADC_CHAN_10_SW_CHAN0_MUX_SEL_MASK GENMASK(9, 7)
#define MESON_SAR_ADC_CHAN_10_SW_CHAN0_VREF_P_MUX BIT(6)
#define MESON_SAR_ADC_CHAN_10_SW_CHAN0_VREF_N_MUX BIT(5)
#define MESON_SAR_ADC_CHAN_10_SW_CHAN0_MODE_SEL BIT(4)
#define MESON_SAR_ADC_CHAN_10_SW_CHAN0_YP_DRIVE_SW BIT(3)
#define MESON_SAR_ADC_CHAN_10_SW_CHAN0_XP_DRIVE_SW BIT(2)
#define MESON_SAR_ADC_CHAN_10_SW_CHAN0_YM_DRIVE_SW BIT(1)
#define MESON_SAR_ADC_CHAN_10_SW_CHAN0_XM_DRIVE_SW BIT(0)
#define MESON_SAR_ADC_DETECT_IDLE_SW 0x24
#define MESON_SAR_ADC_DETECT_IDLE_SW_DETECT_SW_EN BIT(26)
#define MESON_SAR_ADC_DETECT_IDLE_SW_DETECT_MUX_MASK GENMASK(25, 23)
#define MESON_SAR_ADC_DETECT_IDLE_SW_DETECT_VREF_P_MUX BIT(22)
#define MESON_SAR_ADC_DETECT_IDLE_SW_DETECT_VREF_N_MUX BIT(21)
#define MESON_SAR_ADC_DETECT_IDLE_SW_DETECT_MODE_SEL BIT(20)
#define MESON_SAR_ADC_DETECT_IDLE_SW_DETECT_YP_DRIVE_SW BIT(19)
#define MESON_SAR_ADC_DETECT_IDLE_SW_DETECT_XP_DRIVE_SW BIT(18)
#define MESON_SAR_ADC_DETECT_IDLE_SW_DETECT_YM_DRIVE_SW BIT(17)
#define MESON_SAR_ADC_DETECT_IDLE_SW_DETECT_XM_DRIVE_SW BIT(16)
#define MESON_SAR_ADC_DETECT_IDLE_SW_IDLE_MUX_SEL_MASK GENMASK(9, 7)
#define MESON_SAR_ADC_DETECT_IDLE_SW_IDLE_VREF_P_MUX BIT(6)
#define MESON_SAR_ADC_DETECT_IDLE_SW_IDLE_VREF_N_MUX BIT(5)
#define MESON_SAR_ADC_DETECT_IDLE_SW_IDLE_MODE_SEL BIT(4)
#define MESON_SAR_ADC_DETECT_IDLE_SW_IDLE_YP_DRIVE_SW BIT(3)
#define MESON_SAR_ADC_DETECT_IDLE_SW_IDLE_XP_DRIVE_SW BIT(2)
#define MESON_SAR_ADC_DETECT_IDLE_SW_IDLE_YM_DRIVE_SW BIT(1)
#define MESON_SAR_ADC_DETECT_IDLE_SW_IDLE_XM_DRIVE_SW BIT(0)
#define MESON_SAR_ADC_DELTA_10 0x28
#define MESON_SAR_ADC_DELTA_10_TEMP_SEL BIT(27)
#define MESON_SAR_ADC_DELTA_10_TS_REVE1 BIT(26)
#define MESON_SAR_ADC_DELTA_10_CHAN1_DELTA_VALUE_MASK GENMASK(25, 16)
#define MESON_SAR_ADC_DELTA_10_TS_REVE0 BIT(15)
#define MESON_SAR_ADC_DELTA_10_TS_C_MASK GENMASK(14, 11)
#define MESON_SAR_ADC_DELTA_10_TS_VBG_EN BIT(10)
#define MESON_SAR_ADC_DELTA_10_CHAN0_DELTA_VALUE_MASK GENMASK(9, 0)
/*
* NOTE: registers from here are undocumented (the vendor Linux kernel driver
* and u-boot source served as reference). These only seem to be relevant on
* GXBB and newer.
*/
#define MESON_SAR_ADC_REG11 0x2c
#define MESON_SAR_ADC_REG11_BANDGAP_EN BIT(13)
#define MESON_SAR_ADC_REG11_CMV_SEL BIT(6)
#define MESON_SAR_ADC_REG11_VREF_VOLTAGE BIT(5)
#define MESON_SAR_ADC_REG11_EOC BIT(1)
#define MESON_SAR_ADC_REG11_VREF_SEL BIT(0)
iio: adc: add a driver for the SAR ADC found in Amlogic Meson SoCs This adds support for the SAR (Successive Approximation Register) ADC on the Amlogic Meson SoCs. The code is based on the public S805 (Meson8b) and S905 (GXBB) datasheets (see [0] and [1]), as well as by reading (various versions of) the vendor driver and by inspecting the registers on the vendor kernels of my testing-hardware. Currently the GXBB, GXL and GXM SoCs are supported. GXBB hardware has 10-bit ADC resolution, while GXL and GXM have 12-bit ADC resolution. The code was written to support older SoCs (Meson8 and Meson8b) as well, but due to lack of actual testing-hardware no of_device_id was added for these. Two "features" from the vendor driver are currently missing: - the vendor driver uses channel #7 for calibration (this improves the accuracy of the results - in my tests the results were less than 3% off without calibration compared to the vendor driver). Adding support for this should be easy, but is not required for most applications. - channel #6 is connected to the SoCs internal temperature sensor. Adding support for this is probably not so easy since (based on the u-boot sources) most SoC versions are using different registers and algorithms for the conversion from "ADC value" to temperature. Supported by the hardware but currently not supported by the driver: - reading multiple channels at the same time (the hardware has a FIFO buffer which stores multiple results) - continuous sampling (this would require a way to enable this individually because otherwise the ADC would be drawing power constantly) - interrupt support (similar to the vendor driver this new driver is polling the results. It is unclear if the IRQ-mode is supported on older (Meson6 or Meson8) hardware as well or if there are any errata) [0] http://dn.odroid.com/S805/Datasheet/S805_Datasheet%20V0.8%2020150126.pdf [1] http://dn.odroid.com/S905/DataSheet/S905_Public_Datasheet_V1.1.4.pdf Signed-off-by: Martin Blumenstingl <martin.blumenstingl@googlemail.com> Tested-by: Neil Armstrong <narmstrong@baylibre.com> Signed-off-by: Jonathan Cameron <jic23@kernel.org>
2017-01-23 02:17:13 +08:00
#define MESON_SAR_ADC_REG13 0x34
#define MESON_SAR_ADC_REG13_12BIT_CALIBRATION_MASK GENMASK(13, 8)
#define MESON_SAR_ADC_MAX_FIFO_SIZE 32
#define MESON_SAR_ADC_TIMEOUT 100 /* ms */
iio: adc: meson-saradc: add support for the chip's temperature sensor Channel 6 of the SAR ADC can be switched between two inputs: SAR_ADC_CH6 input (an actual pad on the SoC) and the signal from the temperature sensor inside the SoC. To get usable results from the temperature sensor we need to read the corresponding calibration data from the eFuse and pass it to the SAR ADC registers. If the temperature sensor is not calibrated (the eFuse data contains a bit for this) then the driver will only register the iio_chan_spec's for voltage measurements. This only enables the temperature sensor for the Meson8 SoC. Meson8b and Meson8m2 SoCs can be supported in the future as well but we first need a way to pass the fifth TSC (temperature sensor coefficient) bit to the HHI register area (apart from that the infrastructure as already implemented for Meson8 can be used). On the 64-bit SoCs (GXBB, GXL and GXM) the temperature sensor inside SAR ADC is firmware-controlled (by BL30, we can simply use the SCPI hwmon driver to get the chip temperature). To keep the devicetree interface backwards compatible we simply skip the temperature sensor initialization if no eFuse nvmem cell is passed via devicetree. The public documentation for the SAR ADC IP block does not explain how to use the registers to read the temperature. The logic from this patch is based on reading and understanding Amlogic's GPL kernel sources. Signed-off-by: Martin Blumenstingl <martin.blumenstingl@googlemail.com> Signed-off-by: Jonathan Cameron <Jonathan.Cameron@huawei.com>
2018-11-04 07:10:24 +08:00
#define MESON_SAR_ADC_VOLTAGE_AND_TEMP_CHANNEL 6
#define MESON_SAR_ADC_VOLTAGE_AND_MUX_CHANNEL 7
iio: adc: meson-saradc: add support for the chip's temperature sensor Channel 6 of the SAR ADC can be switched between two inputs: SAR_ADC_CH6 input (an actual pad on the SoC) and the signal from the temperature sensor inside the SoC. To get usable results from the temperature sensor we need to read the corresponding calibration data from the eFuse and pass it to the SAR ADC registers. If the temperature sensor is not calibrated (the eFuse data contains a bit for this) then the driver will only register the iio_chan_spec's for voltage measurements. This only enables the temperature sensor for the Meson8 SoC. Meson8b and Meson8m2 SoCs can be supported in the future as well but we first need a way to pass the fifth TSC (temperature sensor coefficient) bit to the HHI register area (apart from that the infrastructure as already implemented for Meson8 can be used). On the 64-bit SoCs (GXBB, GXL and GXM) the temperature sensor inside SAR ADC is firmware-controlled (by BL30, we can simply use the SCPI hwmon driver to get the chip temperature). To keep the devicetree interface backwards compatible we simply skip the temperature sensor initialization if no eFuse nvmem cell is passed via devicetree. The public documentation for the SAR ADC IP block does not explain how to use the registers to read the temperature. The logic from this patch is based on reading and understanding Amlogic's GPL kernel sources. Signed-off-by: Martin Blumenstingl <martin.blumenstingl@googlemail.com> Signed-off-by: Jonathan Cameron <Jonathan.Cameron@huawei.com>
2018-11-04 07:10:24 +08:00
#define MESON_SAR_ADC_TEMP_OFFSET 27
/* temperature sensor calibration information in eFuse */
#define MESON_SAR_ADC_EFUSE_BYTES 4
#define MESON_SAR_ADC_EFUSE_BYTE3_UPPER_ADC_VAL GENMASK(6, 0)
#define MESON_SAR_ADC_EFUSE_BYTE3_IS_CALIBRATED BIT(7)
#define MESON_HHI_DPLL_TOP_0 0x318
#define MESON_HHI_DPLL_TOP_0_TSC_BIT4 BIT(9)
/* for use with IIO_VAL_INT_PLUS_MICRO */
#define MILLION 1000000
iio: adc: add a driver for the SAR ADC found in Amlogic Meson SoCs This adds support for the SAR (Successive Approximation Register) ADC on the Amlogic Meson SoCs. The code is based on the public S805 (Meson8b) and S905 (GXBB) datasheets (see [0] and [1]), as well as by reading (various versions of) the vendor driver and by inspecting the registers on the vendor kernels of my testing-hardware. Currently the GXBB, GXL and GXM SoCs are supported. GXBB hardware has 10-bit ADC resolution, while GXL and GXM have 12-bit ADC resolution. The code was written to support older SoCs (Meson8 and Meson8b) as well, but due to lack of actual testing-hardware no of_device_id was added for these. Two "features" from the vendor driver are currently missing: - the vendor driver uses channel #7 for calibration (this improves the accuracy of the results - in my tests the results were less than 3% off without calibration compared to the vendor driver). Adding support for this should be easy, but is not required for most applications. - channel #6 is connected to the SoCs internal temperature sensor. Adding support for this is probably not so easy since (based on the u-boot sources) most SoC versions are using different registers and algorithms for the conversion from "ADC value" to temperature. Supported by the hardware but currently not supported by the driver: - reading multiple channels at the same time (the hardware has a FIFO buffer which stores multiple results) - continuous sampling (this would require a way to enable this individually because otherwise the ADC would be drawing power constantly) - interrupt support (similar to the vendor driver this new driver is polling the results. It is unclear if the IRQ-mode is supported on older (Meson6 or Meson8) hardware as well or if there are any errata) [0] http://dn.odroid.com/S805/Datasheet/S805_Datasheet%20V0.8%2020150126.pdf [1] http://dn.odroid.com/S905/DataSheet/S905_Public_Datasheet_V1.1.4.pdf Signed-off-by: Martin Blumenstingl <martin.blumenstingl@googlemail.com> Tested-by: Neil Armstrong <narmstrong@baylibre.com> Signed-off-by: Jonathan Cameron <jic23@kernel.org>
2017-01-23 02:17:13 +08:00
#define MESON_SAR_ADC_CHAN(_chan) { \
.type = IIO_VOLTAGE, \
.indexed = 1, \
.channel = _chan, \
.address = _chan, \
iio: adc: add a driver for the SAR ADC found in Amlogic Meson SoCs This adds support for the SAR (Successive Approximation Register) ADC on the Amlogic Meson SoCs. The code is based on the public S805 (Meson8b) and S905 (GXBB) datasheets (see [0] and [1]), as well as by reading (various versions of) the vendor driver and by inspecting the registers on the vendor kernels of my testing-hardware. Currently the GXBB, GXL and GXM SoCs are supported. GXBB hardware has 10-bit ADC resolution, while GXL and GXM have 12-bit ADC resolution. The code was written to support older SoCs (Meson8 and Meson8b) as well, but due to lack of actual testing-hardware no of_device_id was added for these. Two "features" from the vendor driver are currently missing: - the vendor driver uses channel #7 for calibration (this improves the accuracy of the results - in my tests the results were less than 3% off without calibration compared to the vendor driver). Adding support for this should be easy, but is not required for most applications. - channel #6 is connected to the SoCs internal temperature sensor. Adding support for this is probably not so easy since (based on the u-boot sources) most SoC versions are using different registers and algorithms for the conversion from "ADC value" to temperature. Supported by the hardware but currently not supported by the driver: - reading multiple channels at the same time (the hardware has a FIFO buffer which stores multiple results) - continuous sampling (this would require a way to enable this individually because otherwise the ADC would be drawing power constantly) - interrupt support (similar to the vendor driver this new driver is polling the results. It is unclear if the IRQ-mode is supported on older (Meson6 or Meson8) hardware as well or if there are any errata) [0] http://dn.odroid.com/S805/Datasheet/S805_Datasheet%20V0.8%2020150126.pdf [1] http://dn.odroid.com/S905/DataSheet/S905_Public_Datasheet_V1.1.4.pdf Signed-off-by: Martin Blumenstingl <martin.blumenstingl@googlemail.com> Tested-by: Neil Armstrong <narmstrong@baylibre.com> Signed-off-by: Jonathan Cameron <jic23@kernel.org>
2017-01-23 02:17:13 +08:00
.info_mask_separate = BIT(IIO_CHAN_INFO_RAW) | \
BIT(IIO_CHAN_INFO_AVERAGE_RAW), \
iio: adc: meson-saradc: add support for the chip's temperature sensor Channel 6 of the SAR ADC can be switched between two inputs: SAR_ADC_CH6 input (an actual pad on the SoC) and the signal from the temperature sensor inside the SoC. To get usable results from the temperature sensor we need to read the corresponding calibration data from the eFuse and pass it to the SAR ADC registers. If the temperature sensor is not calibrated (the eFuse data contains a bit for this) then the driver will only register the iio_chan_spec's for voltage measurements. This only enables the temperature sensor for the Meson8 SoC. Meson8b and Meson8m2 SoCs can be supported in the future as well but we first need a way to pass the fifth TSC (temperature sensor coefficient) bit to the HHI register area (apart from that the infrastructure as already implemented for Meson8 can be used). On the 64-bit SoCs (GXBB, GXL and GXM) the temperature sensor inside SAR ADC is firmware-controlled (by BL30, we can simply use the SCPI hwmon driver to get the chip temperature). To keep the devicetree interface backwards compatible we simply skip the temperature sensor initialization if no eFuse nvmem cell is passed via devicetree. The public documentation for the SAR ADC IP block does not explain how to use the registers to read the temperature. The logic from this patch is based on reading and understanding Amlogic's GPL kernel sources. Signed-off-by: Martin Blumenstingl <martin.blumenstingl@googlemail.com> Signed-off-by: Jonathan Cameron <Jonathan.Cameron@huawei.com>
2018-11-04 07:10:24 +08:00
.info_mask_shared_by_type = BIT(IIO_CHAN_INFO_SCALE), \
.info_mask_shared_by_all = BIT(IIO_CHAN_INFO_CALIBBIAS) | \
BIT(IIO_CHAN_INFO_CALIBSCALE), \
iio: adc: add a driver for the SAR ADC found in Amlogic Meson SoCs This adds support for the SAR (Successive Approximation Register) ADC on the Amlogic Meson SoCs. The code is based on the public S805 (Meson8b) and S905 (GXBB) datasheets (see [0] and [1]), as well as by reading (various versions of) the vendor driver and by inspecting the registers on the vendor kernels of my testing-hardware. Currently the GXBB, GXL and GXM SoCs are supported. GXBB hardware has 10-bit ADC resolution, while GXL and GXM have 12-bit ADC resolution. The code was written to support older SoCs (Meson8 and Meson8b) as well, but due to lack of actual testing-hardware no of_device_id was added for these. Two "features" from the vendor driver are currently missing: - the vendor driver uses channel #7 for calibration (this improves the accuracy of the results - in my tests the results were less than 3% off without calibration compared to the vendor driver). Adding support for this should be easy, but is not required for most applications. - channel #6 is connected to the SoCs internal temperature sensor. Adding support for this is probably not so easy since (based on the u-boot sources) most SoC versions are using different registers and algorithms for the conversion from "ADC value" to temperature. Supported by the hardware but currently not supported by the driver: - reading multiple channels at the same time (the hardware has a FIFO buffer which stores multiple results) - continuous sampling (this would require a way to enable this individually because otherwise the ADC would be drawing power constantly) - interrupt support (similar to the vendor driver this new driver is polling the results. It is unclear if the IRQ-mode is supported on older (Meson6 or Meson8) hardware as well or if there are any errata) [0] http://dn.odroid.com/S805/Datasheet/S805_Datasheet%20V0.8%2020150126.pdf [1] http://dn.odroid.com/S905/DataSheet/S905_Public_Datasheet_V1.1.4.pdf Signed-off-by: Martin Blumenstingl <martin.blumenstingl@googlemail.com> Tested-by: Neil Armstrong <narmstrong@baylibre.com> Signed-off-by: Jonathan Cameron <jic23@kernel.org>
2017-01-23 02:17:13 +08:00
.datasheet_name = "SAR_ADC_CH"#_chan, \
}
iio: adc: meson-saradc: add support for the chip's temperature sensor Channel 6 of the SAR ADC can be switched between two inputs: SAR_ADC_CH6 input (an actual pad on the SoC) and the signal from the temperature sensor inside the SoC. To get usable results from the temperature sensor we need to read the corresponding calibration data from the eFuse and pass it to the SAR ADC registers. If the temperature sensor is not calibrated (the eFuse data contains a bit for this) then the driver will only register the iio_chan_spec's for voltage measurements. This only enables the temperature sensor for the Meson8 SoC. Meson8b and Meson8m2 SoCs can be supported in the future as well but we first need a way to pass the fifth TSC (temperature sensor coefficient) bit to the HHI register area (apart from that the infrastructure as already implemented for Meson8 can be used). On the 64-bit SoCs (GXBB, GXL and GXM) the temperature sensor inside SAR ADC is firmware-controlled (by BL30, we can simply use the SCPI hwmon driver to get the chip temperature). To keep the devicetree interface backwards compatible we simply skip the temperature sensor initialization if no eFuse nvmem cell is passed via devicetree. The public documentation for the SAR ADC IP block does not explain how to use the registers to read the temperature. The logic from this patch is based on reading and understanding Amlogic's GPL kernel sources. Signed-off-by: Martin Blumenstingl <martin.blumenstingl@googlemail.com> Signed-off-by: Jonathan Cameron <Jonathan.Cameron@huawei.com>
2018-11-04 07:10:24 +08:00
#define MESON_SAR_ADC_TEMP_CHAN(_chan) { \
.type = IIO_TEMP, \
.channel = _chan, \
.address = MESON_SAR_ADC_VOLTAGE_AND_TEMP_CHANNEL, \
.info_mask_separate = BIT(IIO_CHAN_INFO_RAW) | \
BIT(IIO_CHAN_INFO_AVERAGE_RAW), \
.info_mask_shared_by_type = BIT(IIO_CHAN_INFO_OFFSET) | \
BIT(IIO_CHAN_INFO_SCALE), \
.info_mask_shared_by_all = BIT(IIO_CHAN_INFO_CALIBBIAS) | \
BIT(IIO_CHAN_INFO_CALIBSCALE), \
.datasheet_name = "TEMP_SENSOR", \
}
#define MESON_SAR_ADC_MUX(_chan, _sel) { \
.type = IIO_VOLTAGE, \
.channel = _chan, \
.indexed = 1, \
.address = MESON_SAR_ADC_VOLTAGE_AND_MUX_CHANNEL, \
.info_mask_separate = BIT(IIO_CHAN_INFO_RAW) | \
BIT(IIO_CHAN_INFO_AVERAGE_RAW), \
.info_mask_shared_by_type = BIT(IIO_CHAN_INFO_SCALE), \
.info_mask_shared_by_all = BIT(IIO_CHAN_INFO_CALIBBIAS) | \
BIT(IIO_CHAN_INFO_CALIBSCALE), \
.datasheet_name = "SAR_ADC_MUX_"#_sel, \
}
enum meson_sar_adc_vref_sel {
VREF_CALIBATION_VOLTAGE = 0,
VREF_VDDA = 1,
};
enum meson_sar_adc_avg_mode {
NO_AVERAGING = 0x0,
MEAN_AVERAGING = 0x1,
MEDIAN_AVERAGING = 0x2,
};
enum meson_sar_adc_num_samples {
ONE_SAMPLE = 0x0,
TWO_SAMPLES = 0x1,
FOUR_SAMPLES = 0x2,
EIGHT_SAMPLES = 0x3,
};
enum meson_sar_adc_chan7_mux_sel {
CHAN7_MUX_VSS = 0x0,
CHAN7_MUX_VDD_DIV4 = 0x1,
CHAN7_MUX_VDD_DIV2 = 0x2,
CHAN7_MUX_VDD_MUL3_DIV4 = 0x3,
CHAN7_MUX_VDD = 0x4,
CHAN7_MUX_CH7_INPUT = 0x7,
};
enum meson_sar_adc_channel_index {
NUM_CHAN_0,
NUM_CHAN_1,
NUM_CHAN_2,
NUM_CHAN_3,
NUM_CHAN_4,
NUM_CHAN_5,
NUM_CHAN_6,
NUM_CHAN_7,
NUM_CHAN_TEMP,
NUM_MUX_0_VSS,
NUM_MUX_1_VDD_DIV4,
NUM_MUX_2_VDD_DIV2,
NUM_MUX_3_VDD_MUL3_DIV4,
NUM_MUX_4_VDD,
};
static enum meson_sar_adc_chan7_mux_sel chan7_mux_values[] = {
CHAN7_MUX_VSS,
CHAN7_MUX_VDD_DIV4,
CHAN7_MUX_VDD_DIV2,
CHAN7_MUX_VDD_MUL3_DIV4,
CHAN7_MUX_VDD,
};
static const char * const chan7_mux_names[] = {
[CHAN7_MUX_VSS] = "gnd",
[CHAN7_MUX_VDD_DIV4] = "0.25vdd",
[CHAN7_MUX_VDD_DIV2] = "0.5vdd",
[CHAN7_MUX_VDD_MUL3_DIV4] = "0.75vdd",
[CHAN7_MUX_VDD] = "vdd",
};
iio: adc: add a driver for the SAR ADC found in Amlogic Meson SoCs This adds support for the SAR (Successive Approximation Register) ADC on the Amlogic Meson SoCs. The code is based on the public S805 (Meson8b) and S905 (GXBB) datasheets (see [0] and [1]), as well as by reading (various versions of) the vendor driver and by inspecting the registers on the vendor kernels of my testing-hardware. Currently the GXBB, GXL and GXM SoCs are supported. GXBB hardware has 10-bit ADC resolution, while GXL and GXM have 12-bit ADC resolution. The code was written to support older SoCs (Meson8 and Meson8b) as well, but due to lack of actual testing-hardware no of_device_id was added for these. Two "features" from the vendor driver are currently missing: - the vendor driver uses channel #7 for calibration (this improves the accuracy of the results - in my tests the results were less than 3% off without calibration compared to the vendor driver). Adding support for this should be easy, but is not required for most applications. - channel #6 is connected to the SoCs internal temperature sensor. Adding support for this is probably not so easy since (based on the u-boot sources) most SoC versions are using different registers and algorithms for the conversion from "ADC value" to temperature. Supported by the hardware but currently not supported by the driver: - reading multiple channels at the same time (the hardware has a FIFO buffer which stores multiple results) - continuous sampling (this would require a way to enable this individually because otherwise the ADC would be drawing power constantly) - interrupt support (similar to the vendor driver this new driver is polling the results. It is unclear if the IRQ-mode is supported on older (Meson6 or Meson8) hardware as well or if there are any errata) [0] http://dn.odroid.com/S805/Datasheet/S805_Datasheet%20V0.8%2020150126.pdf [1] http://dn.odroid.com/S905/DataSheet/S905_Public_Datasheet_V1.1.4.pdf Signed-off-by: Martin Blumenstingl <martin.blumenstingl@googlemail.com> Tested-by: Neil Armstrong <narmstrong@baylibre.com> Signed-off-by: Jonathan Cameron <jic23@kernel.org>
2017-01-23 02:17:13 +08:00
static const struct iio_chan_spec meson_sar_adc_iio_channels[] = {
MESON_SAR_ADC_CHAN(NUM_CHAN_0),
MESON_SAR_ADC_CHAN(NUM_CHAN_1),
MESON_SAR_ADC_CHAN(NUM_CHAN_2),
MESON_SAR_ADC_CHAN(NUM_CHAN_3),
MESON_SAR_ADC_CHAN(NUM_CHAN_4),
MESON_SAR_ADC_CHAN(NUM_CHAN_5),
MESON_SAR_ADC_CHAN(NUM_CHAN_6),
MESON_SAR_ADC_CHAN(NUM_CHAN_7),
MESON_SAR_ADC_MUX(NUM_MUX_0_VSS, 0),
MESON_SAR_ADC_MUX(NUM_MUX_1_VDD_DIV4, 1),
MESON_SAR_ADC_MUX(NUM_MUX_2_VDD_DIV2, 2),
MESON_SAR_ADC_MUX(NUM_MUX_3_VDD_MUL3_DIV4, 3),
MESON_SAR_ADC_MUX(NUM_MUX_4_VDD, 4),
iio: adc: add a driver for the SAR ADC found in Amlogic Meson SoCs This adds support for the SAR (Successive Approximation Register) ADC on the Amlogic Meson SoCs. The code is based on the public S805 (Meson8b) and S905 (GXBB) datasheets (see [0] and [1]), as well as by reading (various versions of) the vendor driver and by inspecting the registers on the vendor kernels of my testing-hardware. Currently the GXBB, GXL and GXM SoCs are supported. GXBB hardware has 10-bit ADC resolution, while GXL and GXM have 12-bit ADC resolution. The code was written to support older SoCs (Meson8 and Meson8b) as well, but due to lack of actual testing-hardware no of_device_id was added for these. Two "features" from the vendor driver are currently missing: - the vendor driver uses channel #7 for calibration (this improves the accuracy of the results - in my tests the results were less than 3% off without calibration compared to the vendor driver). Adding support for this should be easy, but is not required for most applications. - channel #6 is connected to the SoCs internal temperature sensor. Adding support for this is probably not so easy since (based on the u-boot sources) most SoC versions are using different registers and algorithms for the conversion from "ADC value" to temperature. Supported by the hardware but currently not supported by the driver: - reading multiple channels at the same time (the hardware has a FIFO buffer which stores multiple results) - continuous sampling (this would require a way to enable this individually because otherwise the ADC would be drawing power constantly) - interrupt support (similar to the vendor driver this new driver is polling the results. It is unclear if the IRQ-mode is supported on older (Meson6 or Meson8) hardware as well or if there are any errata) [0] http://dn.odroid.com/S805/Datasheet/S805_Datasheet%20V0.8%2020150126.pdf [1] http://dn.odroid.com/S905/DataSheet/S905_Public_Datasheet_V1.1.4.pdf Signed-off-by: Martin Blumenstingl <martin.blumenstingl@googlemail.com> Tested-by: Neil Armstrong <narmstrong@baylibre.com> Signed-off-by: Jonathan Cameron <jic23@kernel.org>
2017-01-23 02:17:13 +08:00
};
iio: adc: meson-saradc: add support for the chip's temperature sensor Channel 6 of the SAR ADC can be switched between two inputs: SAR_ADC_CH6 input (an actual pad on the SoC) and the signal from the temperature sensor inside the SoC. To get usable results from the temperature sensor we need to read the corresponding calibration data from the eFuse and pass it to the SAR ADC registers. If the temperature sensor is not calibrated (the eFuse data contains a bit for this) then the driver will only register the iio_chan_spec's for voltage measurements. This only enables the temperature sensor for the Meson8 SoC. Meson8b and Meson8m2 SoCs can be supported in the future as well but we first need a way to pass the fifth TSC (temperature sensor coefficient) bit to the HHI register area (apart from that the infrastructure as already implemented for Meson8 can be used). On the 64-bit SoCs (GXBB, GXL and GXM) the temperature sensor inside SAR ADC is firmware-controlled (by BL30, we can simply use the SCPI hwmon driver to get the chip temperature). To keep the devicetree interface backwards compatible we simply skip the temperature sensor initialization if no eFuse nvmem cell is passed via devicetree. The public documentation for the SAR ADC IP block does not explain how to use the registers to read the temperature. The logic from this patch is based on reading and understanding Amlogic's GPL kernel sources. Signed-off-by: Martin Blumenstingl <martin.blumenstingl@googlemail.com> Signed-off-by: Jonathan Cameron <Jonathan.Cameron@huawei.com>
2018-11-04 07:10:24 +08:00
static const struct iio_chan_spec meson_sar_adc_and_temp_iio_channels[] = {
MESON_SAR_ADC_CHAN(NUM_CHAN_0),
MESON_SAR_ADC_CHAN(NUM_CHAN_1),
MESON_SAR_ADC_CHAN(NUM_CHAN_2),
MESON_SAR_ADC_CHAN(NUM_CHAN_3),
MESON_SAR_ADC_CHAN(NUM_CHAN_4),
MESON_SAR_ADC_CHAN(NUM_CHAN_5),
MESON_SAR_ADC_CHAN(NUM_CHAN_6),
MESON_SAR_ADC_CHAN(NUM_CHAN_7),
MESON_SAR_ADC_TEMP_CHAN(NUM_CHAN_TEMP),
MESON_SAR_ADC_MUX(NUM_MUX_0_VSS, 0),
MESON_SAR_ADC_MUX(NUM_MUX_1_VDD_DIV4, 1),
MESON_SAR_ADC_MUX(NUM_MUX_2_VDD_DIV2, 2),
MESON_SAR_ADC_MUX(NUM_MUX_3_VDD_MUL3_DIV4, 3),
MESON_SAR_ADC_MUX(NUM_MUX_4_VDD, 4),
iio: adc: meson-saradc: add support for the chip's temperature sensor Channel 6 of the SAR ADC can be switched between two inputs: SAR_ADC_CH6 input (an actual pad on the SoC) and the signal from the temperature sensor inside the SoC. To get usable results from the temperature sensor we need to read the corresponding calibration data from the eFuse and pass it to the SAR ADC registers. If the temperature sensor is not calibrated (the eFuse data contains a bit for this) then the driver will only register the iio_chan_spec's for voltage measurements. This only enables the temperature sensor for the Meson8 SoC. Meson8b and Meson8m2 SoCs can be supported in the future as well but we first need a way to pass the fifth TSC (temperature sensor coefficient) bit to the HHI register area (apart from that the infrastructure as already implemented for Meson8 can be used). On the 64-bit SoCs (GXBB, GXL and GXM) the temperature sensor inside SAR ADC is firmware-controlled (by BL30, we can simply use the SCPI hwmon driver to get the chip temperature). To keep the devicetree interface backwards compatible we simply skip the temperature sensor initialization if no eFuse nvmem cell is passed via devicetree. The public documentation for the SAR ADC IP block does not explain how to use the registers to read the temperature. The logic from this patch is based on reading and understanding Amlogic's GPL kernel sources. Signed-off-by: Martin Blumenstingl <martin.blumenstingl@googlemail.com> Signed-off-by: Jonathan Cameron <Jonathan.Cameron@huawei.com>
2018-11-04 07:10:24 +08:00
};
struct meson_sar_adc_param {
bool has_bl30_integration;
unsigned long clock_rate;
u32 bandgap_reg;
iio: adc: add a driver for the SAR ADC found in Amlogic Meson SoCs This adds support for the SAR (Successive Approximation Register) ADC on the Amlogic Meson SoCs. The code is based on the public S805 (Meson8b) and S905 (GXBB) datasheets (see [0] and [1]), as well as by reading (various versions of) the vendor driver and by inspecting the registers on the vendor kernels of my testing-hardware. Currently the GXBB, GXL and GXM SoCs are supported. GXBB hardware has 10-bit ADC resolution, while GXL and GXM have 12-bit ADC resolution. The code was written to support older SoCs (Meson8 and Meson8b) as well, but due to lack of actual testing-hardware no of_device_id was added for these. Two "features" from the vendor driver are currently missing: - the vendor driver uses channel #7 for calibration (this improves the accuracy of the results - in my tests the results were less than 3% off without calibration compared to the vendor driver). Adding support for this should be easy, but is not required for most applications. - channel #6 is connected to the SoCs internal temperature sensor. Adding support for this is probably not so easy since (based on the u-boot sources) most SoC versions are using different registers and algorithms for the conversion from "ADC value" to temperature. Supported by the hardware but currently not supported by the driver: - reading multiple channels at the same time (the hardware has a FIFO buffer which stores multiple results) - continuous sampling (this would require a way to enable this individually because otherwise the ADC would be drawing power constantly) - interrupt support (similar to the vendor driver this new driver is polling the results. It is unclear if the IRQ-mode is supported on older (Meson6 or Meson8) hardware as well or if there are any errata) [0] http://dn.odroid.com/S805/Datasheet/S805_Datasheet%20V0.8%2020150126.pdf [1] http://dn.odroid.com/S905/DataSheet/S905_Public_Datasheet_V1.1.4.pdf Signed-off-by: Martin Blumenstingl <martin.blumenstingl@googlemail.com> Tested-by: Neil Armstrong <narmstrong@baylibre.com> Signed-off-by: Jonathan Cameron <jic23@kernel.org>
2017-01-23 02:17:13 +08:00
unsigned int resolution;
const struct regmap_config *regmap_config;
iio: adc: meson-saradc: add support for the chip's temperature sensor Channel 6 of the SAR ADC can be switched between two inputs: SAR_ADC_CH6 input (an actual pad on the SoC) and the signal from the temperature sensor inside the SoC. To get usable results from the temperature sensor we need to read the corresponding calibration data from the eFuse and pass it to the SAR ADC registers. If the temperature sensor is not calibrated (the eFuse data contains a bit for this) then the driver will only register the iio_chan_spec's for voltage measurements. This only enables the temperature sensor for the Meson8 SoC. Meson8b and Meson8m2 SoCs can be supported in the future as well but we first need a way to pass the fifth TSC (temperature sensor coefficient) bit to the HHI register area (apart from that the infrastructure as already implemented for Meson8 can be used). On the 64-bit SoCs (GXBB, GXL and GXM) the temperature sensor inside SAR ADC is firmware-controlled (by BL30, we can simply use the SCPI hwmon driver to get the chip temperature). To keep the devicetree interface backwards compatible we simply skip the temperature sensor initialization if no eFuse nvmem cell is passed via devicetree. The public documentation for the SAR ADC IP block does not explain how to use the registers to read the temperature. The logic from this patch is based on reading and understanding Amlogic's GPL kernel sources. Signed-off-by: Martin Blumenstingl <martin.blumenstingl@googlemail.com> Signed-off-by: Jonathan Cameron <Jonathan.Cameron@huawei.com>
2018-11-04 07:10:24 +08:00
u8 temperature_trimming_bits;
unsigned int temperature_multiplier;
unsigned int temperature_divider;
u8 disable_ring_counter;
bool has_reg11;
bool has_vref_select;
u8 vref_select;
u8 cmv_select;
u8 adc_eoc;
enum meson_sar_adc_vref_sel vref_volatge;
iio: adc: add a driver for the SAR ADC found in Amlogic Meson SoCs This adds support for the SAR (Successive Approximation Register) ADC on the Amlogic Meson SoCs. The code is based on the public S805 (Meson8b) and S905 (GXBB) datasheets (see [0] and [1]), as well as by reading (various versions of) the vendor driver and by inspecting the registers on the vendor kernels of my testing-hardware. Currently the GXBB, GXL and GXM SoCs are supported. GXBB hardware has 10-bit ADC resolution, while GXL and GXM have 12-bit ADC resolution. The code was written to support older SoCs (Meson8 and Meson8b) as well, but due to lack of actual testing-hardware no of_device_id was added for these. Two "features" from the vendor driver are currently missing: - the vendor driver uses channel #7 for calibration (this improves the accuracy of the results - in my tests the results were less than 3% off without calibration compared to the vendor driver). Adding support for this should be easy, but is not required for most applications. - channel #6 is connected to the SoCs internal temperature sensor. Adding support for this is probably not so easy since (based on the u-boot sources) most SoC versions are using different registers and algorithms for the conversion from "ADC value" to temperature. Supported by the hardware but currently not supported by the driver: - reading multiple channels at the same time (the hardware has a FIFO buffer which stores multiple results) - continuous sampling (this would require a way to enable this individually because otherwise the ADC would be drawing power constantly) - interrupt support (similar to the vendor driver this new driver is polling the results. It is unclear if the IRQ-mode is supported on older (Meson6 or Meson8) hardware as well or if there are any errata) [0] http://dn.odroid.com/S805/Datasheet/S805_Datasheet%20V0.8%2020150126.pdf [1] http://dn.odroid.com/S905/DataSheet/S905_Public_Datasheet_V1.1.4.pdf Signed-off-by: Martin Blumenstingl <martin.blumenstingl@googlemail.com> Tested-by: Neil Armstrong <narmstrong@baylibre.com> Signed-off-by: Jonathan Cameron <jic23@kernel.org>
2017-01-23 02:17:13 +08:00
};
struct meson_sar_adc_data {
const struct meson_sar_adc_param *param;
const char *name;
};
iio: adc: add a driver for the SAR ADC found in Amlogic Meson SoCs This adds support for the SAR (Successive Approximation Register) ADC on the Amlogic Meson SoCs. The code is based on the public S805 (Meson8b) and S905 (GXBB) datasheets (see [0] and [1]), as well as by reading (various versions of) the vendor driver and by inspecting the registers on the vendor kernels of my testing-hardware. Currently the GXBB, GXL and GXM SoCs are supported. GXBB hardware has 10-bit ADC resolution, while GXL and GXM have 12-bit ADC resolution. The code was written to support older SoCs (Meson8 and Meson8b) as well, but due to lack of actual testing-hardware no of_device_id was added for these. Two "features" from the vendor driver are currently missing: - the vendor driver uses channel #7 for calibration (this improves the accuracy of the results - in my tests the results were less than 3% off without calibration compared to the vendor driver). Adding support for this should be easy, but is not required for most applications. - channel #6 is connected to the SoCs internal temperature sensor. Adding support for this is probably not so easy since (based on the u-boot sources) most SoC versions are using different registers and algorithms for the conversion from "ADC value" to temperature. Supported by the hardware but currently not supported by the driver: - reading multiple channels at the same time (the hardware has a FIFO buffer which stores multiple results) - continuous sampling (this would require a way to enable this individually because otherwise the ADC would be drawing power constantly) - interrupt support (similar to the vendor driver this new driver is polling the results. It is unclear if the IRQ-mode is supported on older (Meson6 or Meson8) hardware as well or if there are any errata) [0] http://dn.odroid.com/S805/Datasheet/S805_Datasheet%20V0.8%2020150126.pdf [1] http://dn.odroid.com/S905/DataSheet/S905_Public_Datasheet_V1.1.4.pdf Signed-off-by: Martin Blumenstingl <martin.blumenstingl@googlemail.com> Tested-by: Neil Armstrong <narmstrong@baylibre.com> Signed-off-by: Jonathan Cameron <jic23@kernel.org>
2017-01-23 02:17:13 +08:00
struct meson_sar_adc_priv {
struct regmap *regmap;
struct regulator *vref;
const struct meson_sar_adc_param *param;
iio: adc: add a driver for the SAR ADC found in Amlogic Meson SoCs This adds support for the SAR (Successive Approximation Register) ADC on the Amlogic Meson SoCs. The code is based on the public S805 (Meson8b) and S905 (GXBB) datasheets (see [0] and [1]), as well as by reading (various versions of) the vendor driver and by inspecting the registers on the vendor kernels of my testing-hardware. Currently the GXBB, GXL and GXM SoCs are supported. GXBB hardware has 10-bit ADC resolution, while GXL and GXM have 12-bit ADC resolution. The code was written to support older SoCs (Meson8 and Meson8b) as well, but due to lack of actual testing-hardware no of_device_id was added for these. Two "features" from the vendor driver are currently missing: - the vendor driver uses channel #7 for calibration (this improves the accuracy of the results - in my tests the results were less than 3% off without calibration compared to the vendor driver). Adding support for this should be easy, but is not required for most applications. - channel #6 is connected to the SoCs internal temperature sensor. Adding support for this is probably not so easy since (based on the u-boot sources) most SoC versions are using different registers and algorithms for the conversion from "ADC value" to temperature. Supported by the hardware but currently not supported by the driver: - reading multiple channels at the same time (the hardware has a FIFO buffer which stores multiple results) - continuous sampling (this would require a way to enable this individually because otherwise the ADC would be drawing power constantly) - interrupt support (similar to the vendor driver this new driver is polling the results. It is unclear if the IRQ-mode is supported on older (Meson6 or Meson8) hardware as well or if there are any errata) [0] http://dn.odroid.com/S805/Datasheet/S805_Datasheet%20V0.8%2020150126.pdf [1] http://dn.odroid.com/S905/DataSheet/S905_Public_Datasheet_V1.1.4.pdf Signed-off-by: Martin Blumenstingl <martin.blumenstingl@googlemail.com> Tested-by: Neil Armstrong <narmstrong@baylibre.com> Signed-off-by: Jonathan Cameron <jic23@kernel.org>
2017-01-23 02:17:13 +08:00
struct clk *clkin;
struct clk *core_clk;
struct clk *adc_sel_clk;
struct clk *adc_clk;
struct clk_gate clk_gate;
struct clk *adc_div_clk;
struct clk_divider clk_div;
struct completion done;
/* lock to protect against multiple access to the device */
struct mutex lock;
int calibbias;
int calibscale;
struct regmap *tsc_regmap;
iio: adc: meson-saradc: add support for the chip's temperature sensor Channel 6 of the SAR ADC can be switched between two inputs: SAR_ADC_CH6 input (an actual pad on the SoC) and the signal from the temperature sensor inside the SoC. To get usable results from the temperature sensor we need to read the corresponding calibration data from the eFuse and pass it to the SAR ADC registers. If the temperature sensor is not calibrated (the eFuse data contains a bit for this) then the driver will only register the iio_chan_spec's for voltage measurements. This only enables the temperature sensor for the Meson8 SoC. Meson8b and Meson8m2 SoCs can be supported in the future as well but we first need a way to pass the fifth TSC (temperature sensor coefficient) bit to the HHI register area (apart from that the infrastructure as already implemented for Meson8 can be used). On the 64-bit SoCs (GXBB, GXL and GXM) the temperature sensor inside SAR ADC is firmware-controlled (by BL30, we can simply use the SCPI hwmon driver to get the chip temperature). To keep the devicetree interface backwards compatible we simply skip the temperature sensor initialization if no eFuse nvmem cell is passed via devicetree. The public documentation for the SAR ADC IP block does not explain how to use the registers to read the temperature. The logic from this patch is based on reading and understanding Amlogic's GPL kernel sources. Signed-off-by: Martin Blumenstingl <martin.blumenstingl@googlemail.com> Signed-off-by: Jonathan Cameron <Jonathan.Cameron@huawei.com>
2018-11-04 07:10:24 +08:00
bool temperature_sensor_calibrated;
u8 temperature_sensor_coefficient;
u16 temperature_sensor_adc_val;
enum meson_sar_adc_chan7_mux_sel chan7_mux_sel;
iio: adc: add a driver for the SAR ADC found in Amlogic Meson SoCs This adds support for the SAR (Successive Approximation Register) ADC on the Amlogic Meson SoCs. The code is based on the public S805 (Meson8b) and S905 (GXBB) datasheets (see [0] and [1]), as well as by reading (various versions of) the vendor driver and by inspecting the registers on the vendor kernels of my testing-hardware. Currently the GXBB, GXL and GXM SoCs are supported. GXBB hardware has 10-bit ADC resolution, while GXL and GXM have 12-bit ADC resolution. The code was written to support older SoCs (Meson8 and Meson8b) as well, but due to lack of actual testing-hardware no of_device_id was added for these. Two "features" from the vendor driver are currently missing: - the vendor driver uses channel #7 for calibration (this improves the accuracy of the results - in my tests the results were less than 3% off without calibration compared to the vendor driver). Adding support for this should be easy, but is not required for most applications. - channel #6 is connected to the SoCs internal temperature sensor. Adding support for this is probably not so easy since (based on the u-boot sources) most SoC versions are using different registers and algorithms for the conversion from "ADC value" to temperature. Supported by the hardware but currently not supported by the driver: - reading multiple channels at the same time (the hardware has a FIFO buffer which stores multiple results) - continuous sampling (this would require a way to enable this individually because otherwise the ADC would be drawing power constantly) - interrupt support (similar to the vendor driver this new driver is polling the results. It is unclear if the IRQ-mode is supported on older (Meson6 or Meson8) hardware as well or if there are any errata) [0] http://dn.odroid.com/S805/Datasheet/S805_Datasheet%20V0.8%2020150126.pdf [1] http://dn.odroid.com/S905/DataSheet/S905_Public_Datasheet_V1.1.4.pdf Signed-off-by: Martin Blumenstingl <martin.blumenstingl@googlemail.com> Tested-by: Neil Armstrong <narmstrong@baylibre.com> Signed-off-by: Jonathan Cameron <jic23@kernel.org>
2017-01-23 02:17:13 +08:00
};
static const struct regmap_config meson_sar_adc_regmap_config_gxbb = {
iio: adc: add a driver for the SAR ADC found in Amlogic Meson SoCs This adds support for the SAR (Successive Approximation Register) ADC on the Amlogic Meson SoCs. The code is based on the public S805 (Meson8b) and S905 (GXBB) datasheets (see [0] and [1]), as well as by reading (various versions of) the vendor driver and by inspecting the registers on the vendor kernels of my testing-hardware. Currently the GXBB, GXL and GXM SoCs are supported. GXBB hardware has 10-bit ADC resolution, while GXL and GXM have 12-bit ADC resolution. The code was written to support older SoCs (Meson8 and Meson8b) as well, but due to lack of actual testing-hardware no of_device_id was added for these. Two "features" from the vendor driver are currently missing: - the vendor driver uses channel #7 for calibration (this improves the accuracy of the results - in my tests the results were less than 3% off without calibration compared to the vendor driver). Adding support for this should be easy, but is not required for most applications. - channel #6 is connected to the SoCs internal temperature sensor. Adding support for this is probably not so easy since (based on the u-boot sources) most SoC versions are using different registers and algorithms for the conversion from "ADC value" to temperature. Supported by the hardware but currently not supported by the driver: - reading multiple channels at the same time (the hardware has a FIFO buffer which stores multiple results) - continuous sampling (this would require a way to enable this individually because otherwise the ADC would be drawing power constantly) - interrupt support (similar to the vendor driver this new driver is polling the results. It is unclear if the IRQ-mode is supported on older (Meson6 or Meson8) hardware as well or if there are any errata) [0] http://dn.odroid.com/S805/Datasheet/S805_Datasheet%20V0.8%2020150126.pdf [1] http://dn.odroid.com/S905/DataSheet/S905_Public_Datasheet_V1.1.4.pdf Signed-off-by: Martin Blumenstingl <martin.blumenstingl@googlemail.com> Tested-by: Neil Armstrong <narmstrong@baylibre.com> Signed-off-by: Jonathan Cameron <jic23@kernel.org>
2017-01-23 02:17:13 +08:00
.reg_bits = 8,
.val_bits = 32,
.reg_stride = 4,
.max_register = MESON_SAR_ADC_REG13,
};
static const struct regmap_config meson_sar_adc_regmap_config_meson8 = {
.reg_bits = 8,
.val_bits = 32,
.reg_stride = 4,
.max_register = MESON_SAR_ADC_DELTA_10,
};
static const struct iio_chan_spec *
find_channel_by_num(struct iio_dev *indio_dev, int num)
{
int i;
for (i = 0; i < indio_dev->num_channels; i++)
if (indio_dev->channels[i].channel == num)
return &indio_dev->channels[i];
return NULL;
}
iio: adc: add a driver for the SAR ADC found in Amlogic Meson SoCs This adds support for the SAR (Successive Approximation Register) ADC on the Amlogic Meson SoCs. The code is based on the public S805 (Meson8b) and S905 (GXBB) datasheets (see [0] and [1]), as well as by reading (various versions of) the vendor driver and by inspecting the registers on the vendor kernels of my testing-hardware. Currently the GXBB, GXL and GXM SoCs are supported. GXBB hardware has 10-bit ADC resolution, while GXL and GXM have 12-bit ADC resolution. The code was written to support older SoCs (Meson8 and Meson8b) as well, but due to lack of actual testing-hardware no of_device_id was added for these. Two "features" from the vendor driver are currently missing: - the vendor driver uses channel #7 for calibration (this improves the accuracy of the results - in my tests the results were less than 3% off without calibration compared to the vendor driver). Adding support for this should be easy, but is not required for most applications. - channel #6 is connected to the SoCs internal temperature sensor. Adding support for this is probably not so easy since (based on the u-boot sources) most SoC versions are using different registers and algorithms for the conversion from "ADC value" to temperature. Supported by the hardware but currently not supported by the driver: - reading multiple channels at the same time (the hardware has a FIFO buffer which stores multiple results) - continuous sampling (this would require a way to enable this individually because otherwise the ADC would be drawing power constantly) - interrupt support (similar to the vendor driver this new driver is polling the results. It is unclear if the IRQ-mode is supported on older (Meson6 or Meson8) hardware as well or if there are any errata) [0] http://dn.odroid.com/S805/Datasheet/S805_Datasheet%20V0.8%2020150126.pdf [1] http://dn.odroid.com/S905/DataSheet/S905_Public_Datasheet_V1.1.4.pdf Signed-off-by: Martin Blumenstingl <martin.blumenstingl@googlemail.com> Tested-by: Neil Armstrong <narmstrong@baylibre.com> Signed-off-by: Jonathan Cameron <jic23@kernel.org>
2017-01-23 02:17:13 +08:00
static unsigned int meson_sar_adc_get_fifo_count(struct iio_dev *indio_dev)
{
struct meson_sar_adc_priv *priv = iio_priv(indio_dev);
u32 regval;
regmap_read(priv->regmap, MESON_SAR_ADC_REG0, &regval);
return FIELD_GET(MESON_SAR_ADC_REG0_FIFO_COUNT_MASK, regval);
}
static int meson_sar_adc_calib_val(struct iio_dev *indio_dev, int val)
{
struct meson_sar_adc_priv *priv = iio_priv(indio_dev);
int tmp;
/* use val_calib = scale * val_raw + offset calibration function */
tmp = div_s64((s64)val * priv->calibscale, MILLION) + priv->calibbias;
return clamp(tmp, 0, (1 << priv->param->resolution) - 1);
}
iio: adc: add a driver for the SAR ADC found in Amlogic Meson SoCs This adds support for the SAR (Successive Approximation Register) ADC on the Amlogic Meson SoCs. The code is based on the public S805 (Meson8b) and S905 (GXBB) datasheets (see [0] and [1]), as well as by reading (various versions of) the vendor driver and by inspecting the registers on the vendor kernels of my testing-hardware. Currently the GXBB, GXL and GXM SoCs are supported. GXBB hardware has 10-bit ADC resolution, while GXL and GXM have 12-bit ADC resolution. The code was written to support older SoCs (Meson8 and Meson8b) as well, but due to lack of actual testing-hardware no of_device_id was added for these. Two "features" from the vendor driver are currently missing: - the vendor driver uses channel #7 for calibration (this improves the accuracy of the results - in my tests the results were less than 3% off without calibration compared to the vendor driver). Adding support for this should be easy, but is not required for most applications. - channel #6 is connected to the SoCs internal temperature sensor. Adding support for this is probably not so easy since (based on the u-boot sources) most SoC versions are using different registers and algorithms for the conversion from "ADC value" to temperature. Supported by the hardware but currently not supported by the driver: - reading multiple channels at the same time (the hardware has a FIFO buffer which stores multiple results) - continuous sampling (this would require a way to enable this individually because otherwise the ADC would be drawing power constantly) - interrupt support (similar to the vendor driver this new driver is polling the results. It is unclear if the IRQ-mode is supported on older (Meson6 or Meson8) hardware as well or if there are any errata) [0] http://dn.odroid.com/S805/Datasheet/S805_Datasheet%20V0.8%2020150126.pdf [1] http://dn.odroid.com/S905/DataSheet/S905_Public_Datasheet_V1.1.4.pdf Signed-off-by: Martin Blumenstingl <martin.blumenstingl@googlemail.com> Tested-by: Neil Armstrong <narmstrong@baylibre.com> Signed-off-by: Jonathan Cameron <jic23@kernel.org>
2017-01-23 02:17:13 +08:00
static int meson_sar_adc_wait_busy_clear(struct iio_dev *indio_dev)
{
struct meson_sar_adc_priv *priv = iio_priv(indio_dev);
int val;
iio: adc: add a driver for the SAR ADC found in Amlogic Meson SoCs This adds support for the SAR (Successive Approximation Register) ADC on the Amlogic Meson SoCs. The code is based on the public S805 (Meson8b) and S905 (GXBB) datasheets (see [0] and [1]), as well as by reading (various versions of) the vendor driver and by inspecting the registers on the vendor kernels of my testing-hardware. Currently the GXBB, GXL and GXM SoCs are supported. GXBB hardware has 10-bit ADC resolution, while GXL and GXM have 12-bit ADC resolution. The code was written to support older SoCs (Meson8 and Meson8b) as well, but due to lack of actual testing-hardware no of_device_id was added for these. Two "features" from the vendor driver are currently missing: - the vendor driver uses channel #7 for calibration (this improves the accuracy of the results - in my tests the results were less than 3% off without calibration compared to the vendor driver). Adding support for this should be easy, but is not required for most applications. - channel #6 is connected to the SoCs internal temperature sensor. Adding support for this is probably not so easy since (based on the u-boot sources) most SoC versions are using different registers and algorithms for the conversion from "ADC value" to temperature. Supported by the hardware but currently not supported by the driver: - reading multiple channels at the same time (the hardware has a FIFO buffer which stores multiple results) - continuous sampling (this would require a way to enable this individually because otherwise the ADC would be drawing power constantly) - interrupt support (similar to the vendor driver this new driver is polling the results. It is unclear if the IRQ-mode is supported on older (Meson6 or Meson8) hardware as well or if there are any errata) [0] http://dn.odroid.com/S805/Datasheet/S805_Datasheet%20V0.8%2020150126.pdf [1] http://dn.odroid.com/S905/DataSheet/S905_Public_Datasheet_V1.1.4.pdf Signed-off-by: Martin Blumenstingl <martin.blumenstingl@googlemail.com> Tested-by: Neil Armstrong <narmstrong@baylibre.com> Signed-off-by: Jonathan Cameron <jic23@kernel.org>
2017-01-23 02:17:13 +08:00
/*
* NOTE: we need a small delay before reading the status, otherwise
* the sample engine may not have started internally (which would
* seem to us that sampling is already finished).
*/
udelay(1);
return regmap_read_poll_timeout_atomic(priv->regmap, MESON_SAR_ADC_REG0, val,
!FIELD_GET(MESON_SAR_ADC_REG0_BUSY_MASK, val),
1, 10000);
iio: adc: add a driver for the SAR ADC found in Amlogic Meson SoCs This adds support for the SAR (Successive Approximation Register) ADC on the Amlogic Meson SoCs. The code is based on the public S805 (Meson8b) and S905 (GXBB) datasheets (see [0] and [1]), as well as by reading (various versions of) the vendor driver and by inspecting the registers on the vendor kernels of my testing-hardware. Currently the GXBB, GXL and GXM SoCs are supported. GXBB hardware has 10-bit ADC resolution, while GXL and GXM have 12-bit ADC resolution. The code was written to support older SoCs (Meson8 and Meson8b) as well, but due to lack of actual testing-hardware no of_device_id was added for these. Two "features" from the vendor driver are currently missing: - the vendor driver uses channel #7 for calibration (this improves the accuracy of the results - in my tests the results were less than 3% off without calibration compared to the vendor driver). Adding support for this should be easy, but is not required for most applications. - channel #6 is connected to the SoCs internal temperature sensor. Adding support for this is probably not so easy since (based on the u-boot sources) most SoC versions are using different registers and algorithms for the conversion from "ADC value" to temperature. Supported by the hardware but currently not supported by the driver: - reading multiple channels at the same time (the hardware has a FIFO buffer which stores multiple results) - continuous sampling (this would require a way to enable this individually because otherwise the ADC would be drawing power constantly) - interrupt support (similar to the vendor driver this new driver is polling the results. It is unclear if the IRQ-mode is supported on older (Meson6 or Meson8) hardware as well or if there are any errata) [0] http://dn.odroid.com/S805/Datasheet/S805_Datasheet%20V0.8%2020150126.pdf [1] http://dn.odroid.com/S905/DataSheet/S905_Public_Datasheet_V1.1.4.pdf Signed-off-by: Martin Blumenstingl <martin.blumenstingl@googlemail.com> Tested-by: Neil Armstrong <narmstrong@baylibre.com> Signed-off-by: Jonathan Cameron <jic23@kernel.org>
2017-01-23 02:17:13 +08:00
}
static void meson_sar_adc_set_chan7_mux(struct iio_dev *indio_dev,
enum meson_sar_adc_chan7_mux_sel sel)
{
struct meson_sar_adc_priv *priv = iio_priv(indio_dev);
u32 regval;
regval = FIELD_PREP(MESON_SAR_ADC_REG3_CTRL_CHAN7_MUX_SEL_MASK, sel);
regmap_update_bits(priv->regmap, MESON_SAR_ADC_REG3,
MESON_SAR_ADC_REG3_CTRL_CHAN7_MUX_SEL_MASK, regval);
usleep_range(10, 20);
priv->chan7_mux_sel = sel;
}
iio: adc: add a driver for the SAR ADC found in Amlogic Meson SoCs This adds support for the SAR (Successive Approximation Register) ADC on the Amlogic Meson SoCs. The code is based on the public S805 (Meson8b) and S905 (GXBB) datasheets (see [0] and [1]), as well as by reading (various versions of) the vendor driver and by inspecting the registers on the vendor kernels of my testing-hardware. Currently the GXBB, GXL and GXM SoCs are supported. GXBB hardware has 10-bit ADC resolution, while GXL and GXM have 12-bit ADC resolution. The code was written to support older SoCs (Meson8 and Meson8b) as well, but due to lack of actual testing-hardware no of_device_id was added for these. Two "features" from the vendor driver are currently missing: - the vendor driver uses channel #7 for calibration (this improves the accuracy of the results - in my tests the results were less than 3% off without calibration compared to the vendor driver). Adding support for this should be easy, but is not required for most applications. - channel #6 is connected to the SoCs internal temperature sensor. Adding support for this is probably not so easy since (based on the u-boot sources) most SoC versions are using different registers and algorithms for the conversion from "ADC value" to temperature. Supported by the hardware but currently not supported by the driver: - reading multiple channels at the same time (the hardware has a FIFO buffer which stores multiple results) - continuous sampling (this would require a way to enable this individually because otherwise the ADC would be drawing power constantly) - interrupt support (similar to the vendor driver this new driver is polling the results. It is unclear if the IRQ-mode is supported on older (Meson6 or Meson8) hardware as well or if there are any errata) [0] http://dn.odroid.com/S805/Datasheet/S805_Datasheet%20V0.8%2020150126.pdf [1] http://dn.odroid.com/S905/DataSheet/S905_Public_Datasheet_V1.1.4.pdf Signed-off-by: Martin Blumenstingl <martin.blumenstingl@googlemail.com> Tested-by: Neil Armstrong <narmstrong@baylibre.com> Signed-off-by: Jonathan Cameron <jic23@kernel.org>
2017-01-23 02:17:13 +08:00
static int meson_sar_adc_read_raw_sample(struct iio_dev *indio_dev,
const struct iio_chan_spec *chan,
int *val)
{
struct meson_sar_adc_priv *priv = iio_priv(indio_dev);
struct device *dev = indio_dev->dev.parent;
int regval, fifo_chan, fifo_val, count;
iio: adc: add a driver for the SAR ADC found in Amlogic Meson SoCs This adds support for the SAR (Successive Approximation Register) ADC on the Amlogic Meson SoCs. The code is based on the public S805 (Meson8b) and S905 (GXBB) datasheets (see [0] and [1]), as well as by reading (various versions of) the vendor driver and by inspecting the registers on the vendor kernels of my testing-hardware. Currently the GXBB, GXL and GXM SoCs are supported. GXBB hardware has 10-bit ADC resolution, while GXL and GXM have 12-bit ADC resolution. The code was written to support older SoCs (Meson8 and Meson8b) as well, but due to lack of actual testing-hardware no of_device_id was added for these. Two "features" from the vendor driver are currently missing: - the vendor driver uses channel #7 for calibration (this improves the accuracy of the results - in my tests the results were less than 3% off without calibration compared to the vendor driver). Adding support for this should be easy, but is not required for most applications. - channel #6 is connected to the SoCs internal temperature sensor. Adding support for this is probably not so easy since (based on the u-boot sources) most SoC versions are using different registers and algorithms for the conversion from "ADC value" to temperature. Supported by the hardware but currently not supported by the driver: - reading multiple channels at the same time (the hardware has a FIFO buffer which stores multiple results) - continuous sampling (this would require a way to enable this individually because otherwise the ADC would be drawing power constantly) - interrupt support (similar to the vendor driver this new driver is polling the results. It is unclear if the IRQ-mode is supported on older (Meson6 or Meson8) hardware as well or if there are any errata) [0] http://dn.odroid.com/S805/Datasheet/S805_Datasheet%20V0.8%2020150126.pdf [1] http://dn.odroid.com/S905/DataSheet/S905_Public_Datasheet_V1.1.4.pdf Signed-off-by: Martin Blumenstingl <martin.blumenstingl@googlemail.com> Tested-by: Neil Armstrong <narmstrong@baylibre.com> Signed-off-by: Jonathan Cameron <jic23@kernel.org>
2017-01-23 02:17:13 +08:00
if (!wait_for_completion_timeout(&priv->done,
msecs_to_jiffies(MESON_SAR_ADC_TIMEOUT)))
return -ETIMEDOUT;
iio: adc: add a driver for the SAR ADC found in Amlogic Meson SoCs This adds support for the SAR (Successive Approximation Register) ADC on the Amlogic Meson SoCs. The code is based on the public S805 (Meson8b) and S905 (GXBB) datasheets (see [0] and [1]), as well as by reading (various versions of) the vendor driver and by inspecting the registers on the vendor kernels of my testing-hardware. Currently the GXBB, GXL and GXM SoCs are supported. GXBB hardware has 10-bit ADC resolution, while GXL and GXM have 12-bit ADC resolution. The code was written to support older SoCs (Meson8 and Meson8b) as well, but due to lack of actual testing-hardware no of_device_id was added for these. Two "features" from the vendor driver are currently missing: - the vendor driver uses channel #7 for calibration (this improves the accuracy of the results - in my tests the results were less than 3% off without calibration compared to the vendor driver). Adding support for this should be easy, but is not required for most applications. - channel #6 is connected to the SoCs internal temperature sensor. Adding support for this is probably not so easy since (based on the u-boot sources) most SoC versions are using different registers and algorithms for the conversion from "ADC value" to temperature. Supported by the hardware but currently not supported by the driver: - reading multiple channels at the same time (the hardware has a FIFO buffer which stores multiple results) - continuous sampling (this would require a way to enable this individually because otherwise the ADC would be drawing power constantly) - interrupt support (similar to the vendor driver this new driver is polling the results. It is unclear if the IRQ-mode is supported on older (Meson6 or Meson8) hardware as well or if there are any errata) [0] http://dn.odroid.com/S805/Datasheet/S805_Datasheet%20V0.8%2020150126.pdf [1] http://dn.odroid.com/S905/DataSheet/S905_Public_Datasheet_V1.1.4.pdf Signed-off-by: Martin Blumenstingl <martin.blumenstingl@googlemail.com> Tested-by: Neil Armstrong <narmstrong@baylibre.com> Signed-off-by: Jonathan Cameron <jic23@kernel.org>
2017-01-23 02:17:13 +08:00
count = meson_sar_adc_get_fifo_count(indio_dev);
if (count != 1) {
dev_err(dev, "ADC FIFO has %d element(s) instead of one\n", count);
return -EINVAL;
iio: adc: add a driver for the SAR ADC found in Amlogic Meson SoCs This adds support for the SAR (Successive Approximation Register) ADC on the Amlogic Meson SoCs. The code is based on the public S805 (Meson8b) and S905 (GXBB) datasheets (see [0] and [1]), as well as by reading (various versions of) the vendor driver and by inspecting the registers on the vendor kernels of my testing-hardware. Currently the GXBB, GXL and GXM SoCs are supported. GXBB hardware has 10-bit ADC resolution, while GXL and GXM have 12-bit ADC resolution. The code was written to support older SoCs (Meson8 and Meson8b) as well, but due to lack of actual testing-hardware no of_device_id was added for these. Two "features" from the vendor driver are currently missing: - the vendor driver uses channel #7 for calibration (this improves the accuracy of the results - in my tests the results were less than 3% off without calibration compared to the vendor driver). Adding support for this should be easy, but is not required for most applications. - channel #6 is connected to the SoCs internal temperature sensor. Adding support for this is probably not so easy since (based on the u-boot sources) most SoC versions are using different registers and algorithms for the conversion from "ADC value" to temperature. Supported by the hardware but currently not supported by the driver: - reading multiple channels at the same time (the hardware has a FIFO buffer which stores multiple results) - continuous sampling (this would require a way to enable this individually because otherwise the ADC would be drawing power constantly) - interrupt support (similar to the vendor driver this new driver is polling the results. It is unclear if the IRQ-mode is supported on older (Meson6 or Meson8) hardware as well or if there are any errata) [0] http://dn.odroid.com/S805/Datasheet/S805_Datasheet%20V0.8%2020150126.pdf [1] http://dn.odroid.com/S905/DataSheet/S905_Public_Datasheet_V1.1.4.pdf Signed-off-by: Martin Blumenstingl <martin.blumenstingl@googlemail.com> Tested-by: Neil Armstrong <narmstrong@baylibre.com> Signed-off-by: Jonathan Cameron <jic23@kernel.org>
2017-01-23 02:17:13 +08:00
}
regmap_read(priv->regmap, MESON_SAR_ADC_FIFO_RD, &regval);
fifo_chan = FIELD_GET(MESON_SAR_ADC_FIFO_RD_CHAN_ID_MASK, regval);
if (fifo_chan != chan->address) {
dev_err(dev, "ADC FIFO entry belongs to channel %d instead of %lu\n",
fifo_chan, chan->address);
return -EINVAL;
}
iio: adc: add a driver for the SAR ADC found in Amlogic Meson SoCs This adds support for the SAR (Successive Approximation Register) ADC on the Amlogic Meson SoCs. The code is based on the public S805 (Meson8b) and S905 (GXBB) datasheets (see [0] and [1]), as well as by reading (various versions of) the vendor driver and by inspecting the registers on the vendor kernels of my testing-hardware. Currently the GXBB, GXL and GXM SoCs are supported. GXBB hardware has 10-bit ADC resolution, while GXL and GXM have 12-bit ADC resolution. The code was written to support older SoCs (Meson8 and Meson8b) as well, but due to lack of actual testing-hardware no of_device_id was added for these. Two "features" from the vendor driver are currently missing: - the vendor driver uses channel #7 for calibration (this improves the accuracy of the results - in my tests the results were less than 3% off without calibration compared to the vendor driver). Adding support for this should be easy, but is not required for most applications. - channel #6 is connected to the SoCs internal temperature sensor. Adding support for this is probably not so easy since (based on the u-boot sources) most SoC versions are using different registers and algorithms for the conversion from "ADC value" to temperature. Supported by the hardware but currently not supported by the driver: - reading multiple channels at the same time (the hardware has a FIFO buffer which stores multiple results) - continuous sampling (this would require a way to enable this individually because otherwise the ADC would be drawing power constantly) - interrupt support (similar to the vendor driver this new driver is polling the results. It is unclear if the IRQ-mode is supported on older (Meson6 or Meson8) hardware as well or if there are any errata) [0] http://dn.odroid.com/S805/Datasheet/S805_Datasheet%20V0.8%2020150126.pdf [1] http://dn.odroid.com/S905/DataSheet/S905_Public_Datasheet_V1.1.4.pdf Signed-off-by: Martin Blumenstingl <martin.blumenstingl@googlemail.com> Tested-by: Neil Armstrong <narmstrong@baylibre.com> Signed-off-by: Jonathan Cameron <jic23@kernel.org>
2017-01-23 02:17:13 +08:00
fifo_val = FIELD_GET(MESON_SAR_ADC_FIFO_RD_SAMPLE_VALUE_MASK, regval);
fifo_val &= GENMASK(priv->param->resolution - 1, 0);
*val = meson_sar_adc_calib_val(indio_dev, fifo_val);
iio: adc: add a driver for the SAR ADC found in Amlogic Meson SoCs This adds support for the SAR (Successive Approximation Register) ADC on the Amlogic Meson SoCs. The code is based on the public S805 (Meson8b) and S905 (GXBB) datasheets (see [0] and [1]), as well as by reading (various versions of) the vendor driver and by inspecting the registers on the vendor kernels of my testing-hardware. Currently the GXBB, GXL and GXM SoCs are supported. GXBB hardware has 10-bit ADC resolution, while GXL and GXM have 12-bit ADC resolution. The code was written to support older SoCs (Meson8 and Meson8b) as well, but due to lack of actual testing-hardware no of_device_id was added for these. Two "features" from the vendor driver are currently missing: - the vendor driver uses channel #7 for calibration (this improves the accuracy of the results - in my tests the results were less than 3% off without calibration compared to the vendor driver). Adding support for this should be easy, but is not required for most applications. - channel #6 is connected to the SoCs internal temperature sensor. Adding support for this is probably not so easy since (based on the u-boot sources) most SoC versions are using different registers and algorithms for the conversion from "ADC value" to temperature. Supported by the hardware but currently not supported by the driver: - reading multiple channels at the same time (the hardware has a FIFO buffer which stores multiple results) - continuous sampling (this would require a way to enable this individually because otherwise the ADC would be drawing power constantly) - interrupt support (similar to the vendor driver this new driver is polling the results. It is unclear if the IRQ-mode is supported on older (Meson6 or Meson8) hardware as well or if there are any errata) [0] http://dn.odroid.com/S805/Datasheet/S805_Datasheet%20V0.8%2020150126.pdf [1] http://dn.odroid.com/S905/DataSheet/S905_Public_Datasheet_V1.1.4.pdf Signed-off-by: Martin Blumenstingl <martin.blumenstingl@googlemail.com> Tested-by: Neil Armstrong <narmstrong@baylibre.com> Signed-off-by: Jonathan Cameron <jic23@kernel.org>
2017-01-23 02:17:13 +08:00
return 0;
}
static void meson_sar_adc_set_averaging(struct iio_dev *indio_dev,
const struct iio_chan_spec *chan,
enum meson_sar_adc_avg_mode mode,
enum meson_sar_adc_num_samples samples)
{
struct meson_sar_adc_priv *priv = iio_priv(indio_dev);
int val, address = chan->address;
iio: adc: add a driver for the SAR ADC found in Amlogic Meson SoCs This adds support for the SAR (Successive Approximation Register) ADC on the Amlogic Meson SoCs. The code is based on the public S805 (Meson8b) and S905 (GXBB) datasheets (see [0] and [1]), as well as by reading (various versions of) the vendor driver and by inspecting the registers on the vendor kernels of my testing-hardware. Currently the GXBB, GXL and GXM SoCs are supported. GXBB hardware has 10-bit ADC resolution, while GXL and GXM have 12-bit ADC resolution. The code was written to support older SoCs (Meson8 and Meson8b) as well, but due to lack of actual testing-hardware no of_device_id was added for these. Two "features" from the vendor driver are currently missing: - the vendor driver uses channel #7 for calibration (this improves the accuracy of the results - in my tests the results were less than 3% off without calibration compared to the vendor driver). Adding support for this should be easy, but is not required for most applications. - channel #6 is connected to the SoCs internal temperature sensor. Adding support for this is probably not so easy since (based on the u-boot sources) most SoC versions are using different registers and algorithms for the conversion from "ADC value" to temperature. Supported by the hardware but currently not supported by the driver: - reading multiple channels at the same time (the hardware has a FIFO buffer which stores multiple results) - continuous sampling (this would require a way to enable this individually because otherwise the ADC would be drawing power constantly) - interrupt support (similar to the vendor driver this new driver is polling the results. It is unclear if the IRQ-mode is supported on older (Meson6 or Meson8) hardware as well or if there are any errata) [0] http://dn.odroid.com/S805/Datasheet/S805_Datasheet%20V0.8%2020150126.pdf [1] http://dn.odroid.com/S905/DataSheet/S905_Public_Datasheet_V1.1.4.pdf Signed-off-by: Martin Blumenstingl <martin.blumenstingl@googlemail.com> Tested-by: Neil Armstrong <narmstrong@baylibre.com> Signed-off-by: Jonathan Cameron <jic23@kernel.org>
2017-01-23 02:17:13 +08:00
val = samples << MESON_SAR_ADC_AVG_CNTL_NUM_SAMPLES_SHIFT(address);
iio: adc: add a driver for the SAR ADC found in Amlogic Meson SoCs This adds support for the SAR (Successive Approximation Register) ADC on the Amlogic Meson SoCs. The code is based on the public S805 (Meson8b) and S905 (GXBB) datasheets (see [0] and [1]), as well as by reading (various versions of) the vendor driver and by inspecting the registers on the vendor kernels of my testing-hardware. Currently the GXBB, GXL and GXM SoCs are supported. GXBB hardware has 10-bit ADC resolution, while GXL and GXM have 12-bit ADC resolution. The code was written to support older SoCs (Meson8 and Meson8b) as well, but due to lack of actual testing-hardware no of_device_id was added for these. Two "features" from the vendor driver are currently missing: - the vendor driver uses channel #7 for calibration (this improves the accuracy of the results - in my tests the results were less than 3% off without calibration compared to the vendor driver). Adding support for this should be easy, but is not required for most applications. - channel #6 is connected to the SoCs internal temperature sensor. Adding support for this is probably not so easy since (based on the u-boot sources) most SoC versions are using different registers and algorithms for the conversion from "ADC value" to temperature. Supported by the hardware but currently not supported by the driver: - reading multiple channels at the same time (the hardware has a FIFO buffer which stores multiple results) - continuous sampling (this would require a way to enable this individually because otherwise the ADC would be drawing power constantly) - interrupt support (similar to the vendor driver this new driver is polling the results. It is unclear if the IRQ-mode is supported on older (Meson6 or Meson8) hardware as well or if there are any errata) [0] http://dn.odroid.com/S805/Datasheet/S805_Datasheet%20V0.8%2020150126.pdf [1] http://dn.odroid.com/S905/DataSheet/S905_Public_Datasheet_V1.1.4.pdf Signed-off-by: Martin Blumenstingl <martin.blumenstingl@googlemail.com> Tested-by: Neil Armstrong <narmstrong@baylibre.com> Signed-off-by: Jonathan Cameron <jic23@kernel.org>
2017-01-23 02:17:13 +08:00
regmap_update_bits(priv->regmap, MESON_SAR_ADC_AVG_CNTL,
MESON_SAR_ADC_AVG_CNTL_NUM_SAMPLES_MASK(address),
iio: adc: add a driver for the SAR ADC found in Amlogic Meson SoCs This adds support for the SAR (Successive Approximation Register) ADC on the Amlogic Meson SoCs. The code is based on the public S805 (Meson8b) and S905 (GXBB) datasheets (see [0] and [1]), as well as by reading (various versions of) the vendor driver and by inspecting the registers on the vendor kernels of my testing-hardware. Currently the GXBB, GXL and GXM SoCs are supported. GXBB hardware has 10-bit ADC resolution, while GXL and GXM have 12-bit ADC resolution. The code was written to support older SoCs (Meson8 and Meson8b) as well, but due to lack of actual testing-hardware no of_device_id was added for these. Two "features" from the vendor driver are currently missing: - the vendor driver uses channel #7 for calibration (this improves the accuracy of the results - in my tests the results were less than 3% off without calibration compared to the vendor driver). Adding support for this should be easy, but is not required for most applications. - channel #6 is connected to the SoCs internal temperature sensor. Adding support for this is probably not so easy since (based on the u-boot sources) most SoC versions are using different registers and algorithms for the conversion from "ADC value" to temperature. Supported by the hardware but currently not supported by the driver: - reading multiple channels at the same time (the hardware has a FIFO buffer which stores multiple results) - continuous sampling (this would require a way to enable this individually because otherwise the ADC would be drawing power constantly) - interrupt support (similar to the vendor driver this new driver is polling the results. It is unclear if the IRQ-mode is supported on older (Meson6 or Meson8) hardware as well or if there are any errata) [0] http://dn.odroid.com/S805/Datasheet/S805_Datasheet%20V0.8%2020150126.pdf [1] http://dn.odroid.com/S905/DataSheet/S905_Public_Datasheet_V1.1.4.pdf Signed-off-by: Martin Blumenstingl <martin.blumenstingl@googlemail.com> Tested-by: Neil Armstrong <narmstrong@baylibre.com> Signed-off-by: Jonathan Cameron <jic23@kernel.org>
2017-01-23 02:17:13 +08:00
val);
val = mode << MESON_SAR_ADC_AVG_CNTL_AVG_MODE_SHIFT(address);
iio: adc: add a driver for the SAR ADC found in Amlogic Meson SoCs This adds support for the SAR (Successive Approximation Register) ADC on the Amlogic Meson SoCs. The code is based on the public S805 (Meson8b) and S905 (GXBB) datasheets (see [0] and [1]), as well as by reading (various versions of) the vendor driver and by inspecting the registers on the vendor kernels of my testing-hardware. Currently the GXBB, GXL and GXM SoCs are supported. GXBB hardware has 10-bit ADC resolution, while GXL and GXM have 12-bit ADC resolution. The code was written to support older SoCs (Meson8 and Meson8b) as well, but due to lack of actual testing-hardware no of_device_id was added for these. Two "features" from the vendor driver are currently missing: - the vendor driver uses channel #7 for calibration (this improves the accuracy of the results - in my tests the results were less than 3% off without calibration compared to the vendor driver). Adding support for this should be easy, but is not required for most applications. - channel #6 is connected to the SoCs internal temperature sensor. Adding support for this is probably not so easy since (based on the u-boot sources) most SoC versions are using different registers and algorithms for the conversion from "ADC value" to temperature. Supported by the hardware but currently not supported by the driver: - reading multiple channels at the same time (the hardware has a FIFO buffer which stores multiple results) - continuous sampling (this would require a way to enable this individually because otherwise the ADC would be drawing power constantly) - interrupt support (similar to the vendor driver this new driver is polling the results. It is unclear if the IRQ-mode is supported on older (Meson6 or Meson8) hardware as well or if there are any errata) [0] http://dn.odroid.com/S805/Datasheet/S805_Datasheet%20V0.8%2020150126.pdf [1] http://dn.odroid.com/S905/DataSheet/S905_Public_Datasheet_V1.1.4.pdf Signed-off-by: Martin Blumenstingl <martin.blumenstingl@googlemail.com> Tested-by: Neil Armstrong <narmstrong@baylibre.com> Signed-off-by: Jonathan Cameron <jic23@kernel.org>
2017-01-23 02:17:13 +08:00
regmap_update_bits(priv->regmap, MESON_SAR_ADC_AVG_CNTL,
MESON_SAR_ADC_AVG_CNTL_AVG_MODE_MASK(address), val);
iio: adc: add a driver for the SAR ADC found in Amlogic Meson SoCs This adds support for the SAR (Successive Approximation Register) ADC on the Amlogic Meson SoCs. The code is based on the public S805 (Meson8b) and S905 (GXBB) datasheets (see [0] and [1]), as well as by reading (various versions of) the vendor driver and by inspecting the registers on the vendor kernels of my testing-hardware. Currently the GXBB, GXL and GXM SoCs are supported. GXBB hardware has 10-bit ADC resolution, while GXL and GXM have 12-bit ADC resolution. The code was written to support older SoCs (Meson8 and Meson8b) as well, but due to lack of actual testing-hardware no of_device_id was added for these. Two "features" from the vendor driver are currently missing: - the vendor driver uses channel #7 for calibration (this improves the accuracy of the results - in my tests the results were less than 3% off without calibration compared to the vendor driver). Adding support for this should be easy, but is not required for most applications. - channel #6 is connected to the SoCs internal temperature sensor. Adding support for this is probably not so easy since (based on the u-boot sources) most SoC versions are using different registers and algorithms for the conversion from "ADC value" to temperature. Supported by the hardware but currently not supported by the driver: - reading multiple channels at the same time (the hardware has a FIFO buffer which stores multiple results) - continuous sampling (this would require a way to enable this individually because otherwise the ADC would be drawing power constantly) - interrupt support (similar to the vendor driver this new driver is polling the results. It is unclear if the IRQ-mode is supported on older (Meson6 or Meson8) hardware as well or if there are any errata) [0] http://dn.odroid.com/S805/Datasheet/S805_Datasheet%20V0.8%2020150126.pdf [1] http://dn.odroid.com/S905/DataSheet/S905_Public_Datasheet_V1.1.4.pdf Signed-off-by: Martin Blumenstingl <martin.blumenstingl@googlemail.com> Tested-by: Neil Armstrong <narmstrong@baylibre.com> Signed-off-by: Jonathan Cameron <jic23@kernel.org>
2017-01-23 02:17:13 +08:00
}
static void meson_sar_adc_enable_channel(struct iio_dev *indio_dev,
const struct iio_chan_spec *chan)
{
struct meson_sar_adc_priv *priv = iio_priv(indio_dev);
u32 regval;
/*
* the SAR ADC engine allows sampling multiple channels at the same
* time. to keep it simple we're only working with one *internal*
* channel, which starts counting at index 0 (which means: count = 1).
*/
regval = FIELD_PREP(MESON_SAR_ADC_CHAN_LIST_MAX_INDEX_MASK, 0);
regmap_update_bits(priv->regmap, MESON_SAR_ADC_CHAN_LIST,
MESON_SAR_ADC_CHAN_LIST_MAX_INDEX_MASK, regval);
/* map channel index 0 to the channel which we want to read */
regval = FIELD_PREP(MESON_SAR_ADC_CHAN_LIST_ENTRY_MASK(0),
chan->address);
iio: adc: add a driver for the SAR ADC found in Amlogic Meson SoCs This adds support for the SAR (Successive Approximation Register) ADC on the Amlogic Meson SoCs. The code is based on the public S805 (Meson8b) and S905 (GXBB) datasheets (see [0] and [1]), as well as by reading (various versions of) the vendor driver and by inspecting the registers on the vendor kernels of my testing-hardware. Currently the GXBB, GXL and GXM SoCs are supported. GXBB hardware has 10-bit ADC resolution, while GXL and GXM have 12-bit ADC resolution. The code was written to support older SoCs (Meson8 and Meson8b) as well, but due to lack of actual testing-hardware no of_device_id was added for these. Two "features" from the vendor driver are currently missing: - the vendor driver uses channel #7 for calibration (this improves the accuracy of the results - in my tests the results were less than 3% off without calibration compared to the vendor driver). Adding support for this should be easy, but is not required for most applications. - channel #6 is connected to the SoCs internal temperature sensor. Adding support for this is probably not so easy since (based on the u-boot sources) most SoC versions are using different registers and algorithms for the conversion from "ADC value" to temperature. Supported by the hardware but currently not supported by the driver: - reading multiple channels at the same time (the hardware has a FIFO buffer which stores multiple results) - continuous sampling (this would require a way to enable this individually because otherwise the ADC would be drawing power constantly) - interrupt support (similar to the vendor driver this new driver is polling the results. It is unclear if the IRQ-mode is supported on older (Meson6 or Meson8) hardware as well or if there are any errata) [0] http://dn.odroid.com/S805/Datasheet/S805_Datasheet%20V0.8%2020150126.pdf [1] http://dn.odroid.com/S905/DataSheet/S905_Public_Datasheet_V1.1.4.pdf Signed-off-by: Martin Blumenstingl <martin.blumenstingl@googlemail.com> Tested-by: Neil Armstrong <narmstrong@baylibre.com> Signed-off-by: Jonathan Cameron <jic23@kernel.org>
2017-01-23 02:17:13 +08:00
regmap_update_bits(priv->regmap, MESON_SAR_ADC_CHAN_LIST,
MESON_SAR_ADC_CHAN_LIST_ENTRY_MASK(0), regval);
regval = FIELD_PREP(MESON_SAR_ADC_DETECT_IDLE_SW_DETECT_MUX_MASK,
chan->address);
iio: adc: add a driver for the SAR ADC found in Amlogic Meson SoCs This adds support for the SAR (Successive Approximation Register) ADC on the Amlogic Meson SoCs. The code is based on the public S805 (Meson8b) and S905 (GXBB) datasheets (see [0] and [1]), as well as by reading (various versions of) the vendor driver and by inspecting the registers on the vendor kernels of my testing-hardware. Currently the GXBB, GXL and GXM SoCs are supported. GXBB hardware has 10-bit ADC resolution, while GXL and GXM have 12-bit ADC resolution. The code was written to support older SoCs (Meson8 and Meson8b) as well, but due to lack of actual testing-hardware no of_device_id was added for these. Two "features" from the vendor driver are currently missing: - the vendor driver uses channel #7 for calibration (this improves the accuracy of the results - in my tests the results were less than 3% off without calibration compared to the vendor driver). Adding support for this should be easy, but is not required for most applications. - channel #6 is connected to the SoCs internal temperature sensor. Adding support for this is probably not so easy since (based on the u-boot sources) most SoC versions are using different registers and algorithms for the conversion from "ADC value" to temperature. Supported by the hardware but currently not supported by the driver: - reading multiple channels at the same time (the hardware has a FIFO buffer which stores multiple results) - continuous sampling (this would require a way to enable this individually because otherwise the ADC would be drawing power constantly) - interrupt support (similar to the vendor driver this new driver is polling the results. It is unclear if the IRQ-mode is supported on older (Meson6 or Meson8) hardware as well or if there are any errata) [0] http://dn.odroid.com/S805/Datasheet/S805_Datasheet%20V0.8%2020150126.pdf [1] http://dn.odroid.com/S905/DataSheet/S905_Public_Datasheet_V1.1.4.pdf Signed-off-by: Martin Blumenstingl <martin.blumenstingl@googlemail.com> Tested-by: Neil Armstrong <narmstrong@baylibre.com> Signed-off-by: Jonathan Cameron <jic23@kernel.org>
2017-01-23 02:17:13 +08:00
regmap_update_bits(priv->regmap, MESON_SAR_ADC_DETECT_IDLE_SW,
MESON_SAR_ADC_DETECT_IDLE_SW_DETECT_MUX_MASK,
regval);
regval = FIELD_PREP(MESON_SAR_ADC_DETECT_IDLE_SW_IDLE_MUX_SEL_MASK,
chan->address);
iio: adc: add a driver for the SAR ADC found in Amlogic Meson SoCs This adds support for the SAR (Successive Approximation Register) ADC on the Amlogic Meson SoCs. The code is based on the public S805 (Meson8b) and S905 (GXBB) datasheets (see [0] and [1]), as well as by reading (various versions of) the vendor driver and by inspecting the registers on the vendor kernels of my testing-hardware. Currently the GXBB, GXL and GXM SoCs are supported. GXBB hardware has 10-bit ADC resolution, while GXL and GXM have 12-bit ADC resolution. The code was written to support older SoCs (Meson8 and Meson8b) as well, but due to lack of actual testing-hardware no of_device_id was added for these. Two "features" from the vendor driver are currently missing: - the vendor driver uses channel #7 for calibration (this improves the accuracy of the results - in my tests the results were less than 3% off without calibration compared to the vendor driver). Adding support for this should be easy, but is not required for most applications. - channel #6 is connected to the SoCs internal temperature sensor. Adding support for this is probably not so easy since (based on the u-boot sources) most SoC versions are using different registers and algorithms for the conversion from "ADC value" to temperature. Supported by the hardware but currently not supported by the driver: - reading multiple channels at the same time (the hardware has a FIFO buffer which stores multiple results) - continuous sampling (this would require a way to enable this individually because otherwise the ADC would be drawing power constantly) - interrupt support (similar to the vendor driver this new driver is polling the results. It is unclear if the IRQ-mode is supported on older (Meson6 or Meson8) hardware as well or if there are any errata) [0] http://dn.odroid.com/S805/Datasheet/S805_Datasheet%20V0.8%2020150126.pdf [1] http://dn.odroid.com/S905/DataSheet/S905_Public_Datasheet_V1.1.4.pdf Signed-off-by: Martin Blumenstingl <martin.blumenstingl@googlemail.com> Tested-by: Neil Armstrong <narmstrong@baylibre.com> Signed-off-by: Jonathan Cameron <jic23@kernel.org>
2017-01-23 02:17:13 +08:00
regmap_update_bits(priv->regmap, MESON_SAR_ADC_DETECT_IDLE_SW,
MESON_SAR_ADC_DETECT_IDLE_SW_IDLE_MUX_SEL_MASK,
regval);
iio: adc: meson-saradc: add support for the chip's temperature sensor Channel 6 of the SAR ADC can be switched between two inputs: SAR_ADC_CH6 input (an actual pad on the SoC) and the signal from the temperature sensor inside the SoC. To get usable results from the temperature sensor we need to read the corresponding calibration data from the eFuse and pass it to the SAR ADC registers. If the temperature sensor is not calibrated (the eFuse data contains a bit for this) then the driver will only register the iio_chan_spec's for voltage measurements. This only enables the temperature sensor for the Meson8 SoC. Meson8b and Meson8m2 SoCs can be supported in the future as well but we first need a way to pass the fifth TSC (temperature sensor coefficient) bit to the HHI register area (apart from that the infrastructure as already implemented for Meson8 can be used). On the 64-bit SoCs (GXBB, GXL and GXM) the temperature sensor inside SAR ADC is firmware-controlled (by BL30, we can simply use the SCPI hwmon driver to get the chip temperature). To keep the devicetree interface backwards compatible we simply skip the temperature sensor initialization if no eFuse nvmem cell is passed via devicetree. The public documentation for the SAR ADC IP block does not explain how to use the registers to read the temperature. The logic from this patch is based on reading and understanding Amlogic's GPL kernel sources. Signed-off-by: Martin Blumenstingl <martin.blumenstingl@googlemail.com> Signed-off-by: Jonathan Cameron <Jonathan.Cameron@huawei.com>
2018-11-04 07:10:24 +08:00
if (chan->address == MESON_SAR_ADC_VOLTAGE_AND_TEMP_CHANNEL) {
if (chan->type == IIO_TEMP)
regval = MESON_SAR_ADC_DELTA_10_TEMP_SEL;
else
regval = 0;
regmap_update_bits(priv->regmap,
MESON_SAR_ADC_DELTA_10,
MESON_SAR_ADC_DELTA_10_TEMP_SEL, regval);
} else if (chan->address == MESON_SAR_ADC_VOLTAGE_AND_MUX_CHANNEL) {
enum meson_sar_adc_chan7_mux_sel sel;
if (chan->channel == NUM_CHAN_7)
sel = CHAN7_MUX_CH7_INPUT;
else
sel = chan7_mux_values[chan->channel - NUM_MUX_0_VSS];
if (sel != priv->chan7_mux_sel)
meson_sar_adc_set_chan7_mux(indio_dev, sel);
iio: adc: meson-saradc: add support for the chip's temperature sensor Channel 6 of the SAR ADC can be switched between two inputs: SAR_ADC_CH6 input (an actual pad on the SoC) and the signal from the temperature sensor inside the SoC. To get usable results from the temperature sensor we need to read the corresponding calibration data from the eFuse and pass it to the SAR ADC registers. If the temperature sensor is not calibrated (the eFuse data contains a bit for this) then the driver will only register the iio_chan_spec's for voltage measurements. This only enables the temperature sensor for the Meson8 SoC. Meson8b and Meson8m2 SoCs can be supported in the future as well but we first need a way to pass the fifth TSC (temperature sensor coefficient) bit to the HHI register area (apart from that the infrastructure as already implemented for Meson8 can be used). On the 64-bit SoCs (GXBB, GXL and GXM) the temperature sensor inside SAR ADC is firmware-controlled (by BL30, we can simply use the SCPI hwmon driver to get the chip temperature). To keep the devicetree interface backwards compatible we simply skip the temperature sensor initialization if no eFuse nvmem cell is passed via devicetree. The public documentation for the SAR ADC IP block does not explain how to use the registers to read the temperature. The logic from this patch is based on reading and understanding Amlogic's GPL kernel sources. Signed-off-by: Martin Blumenstingl <martin.blumenstingl@googlemail.com> Signed-off-by: Jonathan Cameron <Jonathan.Cameron@huawei.com>
2018-11-04 07:10:24 +08:00
}
iio: adc: add a driver for the SAR ADC found in Amlogic Meson SoCs This adds support for the SAR (Successive Approximation Register) ADC on the Amlogic Meson SoCs. The code is based on the public S805 (Meson8b) and S905 (GXBB) datasheets (see [0] and [1]), as well as by reading (various versions of) the vendor driver and by inspecting the registers on the vendor kernels of my testing-hardware. Currently the GXBB, GXL and GXM SoCs are supported. GXBB hardware has 10-bit ADC resolution, while GXL and GXM have 12-bit ADC resolution. The code was written to support older SoCs (Meson8 and Meson8b) as well, but due to lack of actual testing-hardware no of_device_id was added for these. Two "features" from the vendor driver are currently missing: - the vendor driver uses channel #7 for calibration (this improves the accuracy of the results - in my tests the results were less than 3% off without calibration compared to the vendor driver). Adding support for this should be easy, but is not required for most applications. - channel #6 is connected to the SoCs internal temperature sensor. Adding support for this is probably not so easy since (based on the u-boot sources) most SoC versions are using different registers and algorithms for the conversion from "ADC value" to temperature. Supported by the hardware but currently not supported by the driver: - reading multiple channels at the same time (the hardware has a FIFO buffer which stores multiple results) - continuous sampling (this would require a way to enable this individually because otherwise the ADC would be drawing power constantly) - interrupt support (similar to the vendor driver this new driver is polling the results. It is unclear if the IRQ-mode is supported on older (Meson6 or Meson8) hardware as well or if there are any errata) [0] http://dn.odroid.com/S805/Datasheet/S805_Datasheet%20V0.8%2020150126.pdf [1] http://dn.odroid.com/S905/DataSheet/S905_Public_Datasheet_V1.1.4.pdf Signed-off-by: Martin Blumenstingl <martin.blumenstingl@googlemail.com> Tested-by: Neil Armstrong <narmstrong@baylibre.com> Signed-off-by: Jonathan Cameron <jic23@kernel.org>
2017-01-23 02:17:13 +08:00
}
static void meson_sar_adc_start_sample_engine(struct iio_dev *indio_dev)
{
struct meson_sar_adc_priv *priv = iio_priv(indio_dev);
reinit_completion(&priv->done);
regmap_update_bits(priv->regmap, MESON_SAR_ADC_REG0,
MESON_SAR_ADC_REG0_FIFO_IRQ_EN,
MESON_SAR_ADC_REG0_FIFO_IRQ_EN);
iio: adc: add a driver for the SAR ADC found in Amlogic Meson SoCs This adds support for the SAR (Successive Approximation Register) ADC on the Amlogic Meson SoCs. The code is based on the public S805 (Meson8b) and S905 (GXBB) datasheets (see [0] and [1]), as well as by reading (various versions of) the vendor driver and by inspecting the registers on the vendor kernels of my testing-hardware. Currently the GXBB, GXL and GXM SoCs are supported. GXBB hardware has 10-bit ADC resolution, while GXL and GXM have 12-bit ADC resolution. The code was written to support older SoCs (Meson8 and Meson8b) as well, but due to lack of actual testing-hardware no of_device_id was added for these. Two "features" from the vendor driver are currently missing: - the vendor driver uses channel #7 for calibration (this improves the accuracy of the results - in my tests the results were less than 3% off without calibration compared to the vendor driver). Adding support for this should be easy, but is not required for most applications. - channel #6 is connected to the SoCs internal temperature sensor. Adding support for this is probably not so easy since (based on the u-boot sources) most SoC versions are using different registers and algorithms for the conversion from "ADC value" to temperature. Supported by the hardware but currently not supported by the driver: - reading multiple channels at the same time (the hardware has a FIFO buffer which stores multiple results) - continuous sampling (this would require a way to enable this individually because otherwise the ADC would be drawing power constantly) - interrupt support (similar to the vendor driver this new driver is polling the results. It is unclear if the IRQ-mode is supported on older (Meson6 or Meson8) hardware as well or if there are any errata) [0] http://dn.odroid.com/S805/Datasheet/S805_Datasheet%20V0.8%2020150126.pdf [1] http://dn.odroid.com/S905/DataSheet/S905_Public_Datasheet_V1.1.4.pdf Signed-off-by: Martin Blumenstingl <martin.blumenstingl@googlemail.com> Tested-by: Neil Armstrong <narmstrong@baylibre.com> Signed-off-by: Jonathan Cameron <jic23@kernel.org>
2017-01-23 02:17:13 +08:00
regmap_update_bits(priv->regmap, MESON_SAR_ADC_REG0,
MESON_SAR_ADC_REG0_SAMPLE_ENGINE_ENABLE,
MESON_SAR_ADC_REG0_SAMPLE_ENGINE_ENABLE);
regmap_update_bits(priv->regmap, MESON_SAR_ADC_REG0,
MESON_SAR_ADC_REG0_SAMPLING_START,
MESON_SAR_ADC_REG0_SAMPLING_START);
}
static void meson_sar_adc_stop_sample_engine(struct iio_dev *indio_dev)
{
struct meson_sar_adc_priv *priv = iio_priv(indio_dev);
regmap_update_bits(priv->regmap, MESON_SAR_ADC_REG0,
MESON_SAR_ADC_REG0_FIFO_IRQ_EN, 0);
iio: adc: add a driver for the SAR ADC found in Amlogic Meson SoCs This adds support for the SAR (Successive Approximation Register) ADC on the Amlogic Meson SoCs. The code is based on the public S805 (Meson8b) and S905 (GXBB) datasheets (see [0] and [1]), as well as by reading (various versions of) the vendor driver and by inspecting the registers on the vendor kernels of my testing-hardware. Currently the GXBB, GXL and GXM SoCs are supported. GXBB hardware has 10-bit ADC resolution, while GXL and GXM have 12-bit ADC resolution. The code was written to support older SoCs (Meson8 and Meson8b) as well, but due to lack of actual testing-hardware no of_device_id was added for these. Two "features" from the vendor driver are currently missing: - the vendor driver uses channel #7 for calibration (this improves the accuracy of the results - in my tests the results were less than 3% off without calibration compared to the vendor driver). Adding support for this should be easy, but is not required for most applications. - channel #6 is connected to the SoCs internal temperature sensor. Adding support for this is probably not so easy since (based on the u-boot sources) most SoC versions are using different registers and algorithms for the conversion from "ADC value" to temperature. Supported by the hardware but currently not supported by the driver: - reading multiple channels at the same time (the hardware has a FIFO buffer which stores multiple results) - continuous sampling (this would require a way to enable this individually because otherwise the ADC would be drawing power constantly) - interrupt support (similar to the vendor driver this new driver is polling the results. It is unclear if the IRQ-mode is supported on older (Meson6 or Meson8) hardware as well or if there are any errata) [0] http://dn.odroid.com/S805/Datasheet/S805_Datasheet%20V0.8%2020150126.pdf [1] http://dn.odroid.com/S905/DataSheet/S905_Public_Datasheet_V1.1.4.pdf Signed-off-by: Martin Blumenstingl <martin.blumenstingl@googlemail.com> Tested-by: Neil Armstrong <narmstrong@baylibre.com> Signed-off-by: Jonathan Cameron <jic23@kernel.org>
2017-01-23 02:17:13 +08:00
regmap_update_bits(priv->regmap, MESON_SAR_ADC_REG0,
MESON_SAR_ADC_REG0_SAMPLING_STOP,
MESON_SAR_ADC_REG0_SAMPLING_STOP);
/* wait until all modules are stopped */
meson_sar_adc_wait_busy_clear(indio_dev);
regmap_update_bits(priv->regmap, MESON_SAR_ADC_REG0,
MESON_SAR_ADC_REG0_SAMPLE_ENGINE_ENABLE, 0);
}
static int meson_sar_adc_lock(struct iio_dev *indio_dev)
{
struct meson_sar_adc_priv *priv = iio_priv(indio_dev);
int val, ret;
iio: adc: add a driver for the SAR ADC found in Amlogic Meson SoCs This adds support for the SAR (Successive Approximation Register) ADC on the Amlogic Meson SoCs. The code is based on the public S805 (Meson8b) and S905 (GXBB) datasheets (see [0] and [1]), as well as by reading (various versions of) the vendor driver and by inspecting the registers on the vendor kernels of my testing-hardware. Currently the GXBB, GXL and GXM SoCs are supported. GXBB hardware has 10-bit ADC resolution, while GXL and GXM have 12-bit ADC resolution. The code was written to support older SoCs (Meson8 and Meson8b) as well, but due to lack of actual testing-hardware no of_device_id was added for these. Two "features" from the vendor driver are currently missing: - the vendor driver uses channel #7 for calibration (this improves the accuracy of the results - in my tests the results were less than 3% off without calibration compared to the vendor driver). Adding support for this should be easy, but is not required for most applications. - channel #6 is connected to the SoCs internal temperature sensor. Adding support for this is probably not so easy since (based on the u-boot sources) most SoC versions are using different registers and algorithms for the conversion from "ADC value" to temperature. Supported by the hardware but currently not supported by the driver: - reading multiple channels at the same time (the hardware has a FIFO buffer which stores multiple results) - continuous sampling (this would require a way to enable this individually because otherwise the ADC would be drawing power constantly) - interrupt support (similar to the vendor driver this new driver is polling the results. It is unclear if the IRQ-mode is supported on older (Meson6 or Meson8) hardware as well or if there are any errata) [0] http://dn.odroid.com/S805/Datasheet/S805_Datasheet%20V0.8%2020150126.pdf [1] http://dn.odroid.com/S905/DataSheet/S905_Public_Datasheet_V1.1.4.pdf Signed-off-by: Martin Blumenstingl <martin.blumenstingl@googlemail.com> Tested-by: Neil Armstrong <narmstrong@baylibre.com> Signed-off-by: Jonathan Cameron <jic23@kernel.org>
2017-01-23 02:17:13 +08:00
mutex_lock(&priv->lock);
iio: adc: add a driver for the SAR ADC found in Amlogic Meson SoCs This adds support for the SAR (Successive Approximation Register) ADC on the Amlogic Meson SoCs. The code is based on the public S805 (Meson8b) and S905 (GXBB) datasheets (see [0] and [1]), as well as by reading (various versions of) the vendor driver and by inspecting the registers on the vendor kernels of my testing-hardware. Currently the GXBB, GXL and GXM SoCs are supported. GXBB hardware has 10-bit ADC resolution, while GXL and GXM have 12-bit ADC resolution. The code was written to support older SoCs (Meson8 and Meson8b) as well, but due to lack of actual testing-hardware no of_device_id was added for these. Two "features" from the vendor driver are currently missing: - the vendor driver uses channel #7 for calibration (this improves the accuracy of the results - in my tests the results were less than 3% off without calibration compared to the vendor driver). Adding support for this should be easy, but is not required for most applications. - channel #6 is connected to the SoCs internal temperature sensor. Adding support for this is probably not so easy since (based on the u-boot sources) most SoC versions are using different registers and algorithms for the conversion from "ADC value" to temperature. Supported by the hardware but currently not supported by the driver: - reading multiple channels at the same time (the hardware has a FIFO buffer which stores multiple results) - continuous sampling (this would require a way to enable this individually because otherwise the ADC would be drawing power constantly) - interrupt support (similar to the vendor driver this new driver is polling the results. It is unclear if the IRQ-mode is supported on older (Meson6 or Meson8) hardware as well or if there are any errata) [0] http://dn.odroid.com/S805/Datasheet/S805_Datasheet%20V0.8%2020150126.pdf [1] http://dn.odroid.com/S905/DataSheet/S905_Public_Datasheet_V1.1.4.pdf Signed-off-by: Martin Blumenstingl <martin.blumenstingl@googlemail.com> Tested-by: Neil Armstrong <narmstrong@baylibre.com> Signed-off-by: Jonathan Cameron <jic23@kernel.org>
2017-01-23 02:17:13 +08:00
if (priv->param->has_bl30_integration) {
/* prevent BL30 from using the SAR ADC while we are using it */
regmap_update_bits(priv->regmap, MESON_SAR_ADC_DELAY,
MESON_SAR_ADC_DELAY_KERNEL_BUSY,
MESON_SAR_ADC_DELAY_KERNEL_BUSY);
udelay(1);
/*
* wait until BL30 releases it's lock (so we can use the SAR
* ADC)
*/
ret = regmap_read_poll_timeout_atomic(priv->regmap, MESON_SAR_ADC_DELAY, val,
!(val & MESON_SAR_ADC_DELAY_BL30_BUSY),
1, 10000);
if (ret) {
mutex_unlock(&priv->lock);
return ret;
}
}
iio: adc: add a driver for the SAR ADC found in Amlogic Meson SoCs This adds support for the SAR (Successive Approximation Register) ADC on the Amlogic Meson SoCs. The code is based on the public S805 (Meson8b) and S905 (GXBB) datasheets (see [0] and [1]), as well as by reading (various versions of) the vendor driver and by inspecting the registers on the vendor kernels of my testing-hardware. Currently the GXBB, GXL and GXM SoCs are supported. GXBB hardware has 10-bit ADC resolution, while GXL and GXM have 12-bit ADC resolution. The code was written to support older SoCs (Meson8 and Meson8b) as well, but due to lack of actual testing-hardware no of_device_id was added for these. Two "features" from the vendor driver are currently missing: - the vendor driver uses channel #7 for calibration (this improves the accuracy of the results - in my tests the results were less than 3% off without calibration compared to the vendor driver). Adding support for this should be easy, but is not required for most applications. - channel #6 is connected to the SoCs internal temperature sensor. Adding support for this is probably not so easy since (based on the u-boot sources) most SoC versions are using different registers and algorithms for the conversion from "ADC value" to temperature. Supported by the hardware but currently not supported by the driver: - reading multiple channels at the same time (the hardware has a FIFO buffer which stores multiple results) - continuous sampling (this would require a way to enable this individually because otherwise the ADC would be drawing power constantly) - interrupt support (similar to the vendor driver this new driver is polling the results. It is unclear if the IRQ-mode is supported on older (Meson6 or Meson8) hardware as well or if there are any errata) [0] http://dn.odroid.com/S805/Datasheet/S805_Datasheet%20V0.8%2020150126.pdf [1] http://dn.odroid.com/S905/DataSheet/S905_Public_Datasheet_V1.1.4.pdf Signed-off-by: Martin Blumenstingl <martin.blumenstingl@googlemail.com> Tested-by: Neil Armstrong <narmstrong@baylibre.com> Signed-off-by: Jonathan Cameron <jic23@kernel.org>
2017-01-23 02:17:13 +08:00
return 0;
}
static void meson_sar_adc_unlock(struct iio_dev *indio_dev)
{
struct meson_sar_adc_priv *priv = iio_priv(indio_dev);
if (priv->param->has_bl30_integration)
/* allow BL30 to use the SAR ADC again */
regmap_update_bits(priv->regmap, MESON_SAR_ADC_DELAY,
MESON_SAR_ADC_DELAY_KERNEL_BUSY, 0);
iio: adc: add a driver for the SAR ADC found in Amlogic Meson SoCs This adds support for the SAR (Successive Approximation Register) ADC on the Amlogic Meson SoCs. The code is based on the public S805 (Meson8b) and S905 (GXBB) datasheets (see [0] and [1]), as well as by reading (various versions of) the vendor driver and by inspecting the registers on the vendor kernels of my testing-hardware. Currently the GXBB, GXL and GXM SoCs are supported. GXBB hardware has 10-bit ADC resolution, while GXL and GXM have 12-bit ADC resolution. The code was written to support older SoCs (Meson8 and Meson8b) as well, but due to lack of actual testing-hardware no of_device_id was added for these. Two "features" from the vendor driver are currently missing: - the vendor driver uses channel #7 for calibration (this improves the accuracy of the results - in my tests the results were less than 3% off without calibration compared to the vendor driver). Adding support for this should be easy, but is not required for most applications. - channel #6 is connected to the SoCs internal temperature sensor. Adding support for this is probably not so easy since (based on the u-boot sources) most SoC versions are using different registers and algorithms for the conversion from "ADC value" to temperature. Supported by the hardware but currently not supported by the driver: - reading multiple channels at the same time (the hardware has a FIFO buffer which stores multiple results) - continuous sampling (this would require a way to enable this individually because otherwise the ADC would be drawing power constantly) - interrupt support (similar to the vendor driver this new driver is polling the results. It is unclear if the IRQ-mode is supported on older (Meson6 or Meson8) hardware as well or if there are any errata) [0] http://dn.odroid.com/S805/Datasheet/S805_Datasheet%20V0.8%2020150126.pdf [1] http://dn.odroid.com/S905/DataSheet/S905_Public_Datasheet_V1.1.4.pdf Signed-off-by: Martin Blumenstingl <martin.blumenstingl@googlemail.com> Tested-by: Neil Armstrong <narmstrong@baylibre.com> Signed-off-by: Jonathan Cameron <jic23@kernel.org>
2017-01-23 02:17:13 +08:00
mutex_unlock(&priv->lock);
iio: adc: add a driver for the SAR ADC found in Amlogic Meson SoCs This adds support for the SAR (Successive Approximation Register) ADC on the Amlogic Meson SoCs. The code is based on the public S805 (Meson8b) and S905 (GXBB) datasheets (see [0] and [1]), as well as by reading (various versions of) the vendor driver and by inspecting the registers on the vendor kernels of my testing-hardware. Currently the GXBB, GXL and GXM SoCs are supported. GXBB hardware has 10-bit ADC resolution, while GXL and GXM have 12-bit ADC resolution. The code was written to support older SoCs (Meson8 and Meson8b) as well, but due to lack of actual testing-hardware no of_device_id was added for these. Two "features" from the vendor driver are currently missing: - the vendor driver uses channel #7 for calibration (this improves the accuracy of the results - in my tests the results were less than 3% off without calibration compared to the vendor driver). Adding support for this should be easy, but is not required for most applications. - channel #6 is connected to the SoCs internal temperature sensor. Adding support for this is probably not so easy since (based on the u-boot sources) most SoC versions are using different registers and algorithms for the conversion from "ADC value" to temperature. Supported by the hardware but currently not supported by the driver: - reading multiple channels at the same time (the hardware has a FIFO buffer which stores multiple results) - continuous sampling (this would require a way to enable this individually because otherwise the ADC would be drawing power constantly) - interrupt support (similar to the vendor driver this new driver is polling the results. It is unclear if the IRQ-mode is supported on older (Meson6 or Meson8) hardware as well or if there are any errata) [0] http://dn.odroid.com/S805/Datasheet/S805_Datasheet%20V0.8%2020150126.pdf [1] http://dn.odroid.com/S905/DataSheet/S905_Public_Datasheet_V1.1.4.pdf Signed-off-by: Martin Blumenstingl <martin.blumenstingl@googlemail.com> Tested-by: Neil Armstrong <narmstrong@baylibre.com> Signed-off-by: Jonathan Cameron <jic23@kernel.org>
2017-01-23 02:17:13 +08:00
}
static void meson_sar_adc_clear_fifo(struct iio_dev *indio_dev)
{
struct meson_sar_adc_priv *priv = iio_priv(indio_dev);
unsigned int count, tmp;
iio: adc: add a driver for the SAR ADC found in Amlogic Meson SoCs This adds support for the SAR (Successive Approximation Register) ADC on the Amlogic Meson SoCs. The code is based on the public S805 (Meson8b) and S905 (GXBB) datasheets (see [0] and [1]), as well as by reading (various versions of) the vendor driver and by inspecting the registers on the vendor kernels of my testing-hardware. Currently the GXBB, GXL and GXM SoCs are supported. GXBB hardware has 10-bit ADC resolution, while GXL and GXM have 12-bit ADC resolution. The code was written to support older SoCs (Meson8 and Meson8b) as well, but due to lack of actual testing-hardware no of_device_id was added for these. Two "features" from the vendor driver are currently missing: - the vendor driver uses channel #7 for calibration (this improves the accuracy of the results - in my tests the results were less than 3% off without calibration compared to the vendor driver). Adding support for this should be easy, but is not required for most applications. - channel #6 is connected to the SoCs internal temperature sensor. Adding support for this is probably not so easy since (based on the u-boot sources) most SoC versions are using different registers and algorithms for the conversion from "ADC value" to temperature. Supported by the hardware but currently not supported by the driver: - reading multiple channels at the same time (the hardware has a FIFO buffer which stores multiple results) - continuous sampling (this would require a way to enable this individually because otherwise the ADC would be drawing power constantly) - interrupt support (similar to the vendor driver this new driver is polling the results. It is unclear if the IRQ-mode is supported on older (Meson6 or Meson8) hardware as well or if there are any errata) [0] http://dn.odroid.com/S805/Datasheet/S805_Datasheet%20V0.8%2020150126.pdf [1] http://dn.odroid.com/S905/DataSheet/S905_Public_Datasheet_V1.1.4.pdf Signed-off-by: Martin Blumenstingl <martin.blumenstingl@googlemail.com> Tested-by: Neil Armstrong <narmstrong@baylibre.com> Signed-off-by: Jonathan Cameron <jic23@kernel.org>
2017-01-23 02:17:13 +08:00
for (count = 0; count < MESON_SAR_ADC_MAX_FIFO_SIZE; count++) {
if (!meson_sar_adc_get_fifo_count(indio_dev))
break;
regmap_read(priv->regmap, MESON_SAR_ADC_FIFO_RD, &tmp);
iio: adc: add a driver for the SAR ADC found in Amlogic Meson SoCs This adds support for the SAR (Successive Approximation Register) ADC on the Amlogic Meson SoCs. The code is based on the public S805 (Meson8b) and S905 (GXBB) datasheets (see [0] and [1]), as well as by reading (various versions of) the vendor driver and by inspecting the registers on the vendor kernels of my testing-hardware. Currently the GXBB, GXL and GXM SoCs are supported. GXBB hardware has 10-bit ADC resolution, while GXL and GXM have 12-bit ADC resolution. The code was written to support older SoCs (Meson8 and Meson8b) as well, but due to lack of actual testing-hardware no of_device_id was added for these. Two "features" from the vendor driver are currently missing: - the vendor driver uses channel #7 for calibration (this improves the accuracy of the results - in my tests the results were less than 3% off without calibration compared to the vendor driver). Adding support for this should be easy, but is not required for most applications. - channel #6 is connected to the SoCs internal temperature sensor. Adding support for this is probably not so easy since (based on the u-boot sources) most SoC versions are using different registers and algorithms for the conversion from "ADC value" to temperature. Supported by the hardware but currently not supported by the driver: - reading multiple channels at the same time (the hardware has a FIFO buffer which stores multiple results) - continuous sampling (this would require a way to enable this individually because otherwise the ADC would be drawing power constantly) - interrupt support (similar to the vendor driver this new driver is polling the results. It is unclear if the IRQ-mode is supported on older (Meson6 or Meson8) hardware as well or if there are any errata) [0] http://dn.odroid.com/S805/Datasheet/S805_Datasheet%20V0.8%2020150126.pdf [1] http://dn.odroid.com/S905/DataSheet/S905_Public_Datasheet_V1.1.4.pdf Signed-off-by: Martin Blumenstingl <martin.blumenstingl@googlemail.com> Tested-by: Neil Armstrong <narmstrong@baylibre.com> Signed-off-by: Jonathan Cameron <jic23@kernel.org>
2017-01-23 02:17:13 +08:00
}
}
static int meson_sar_adc_get_sample(struct iio_dev *indio_dev,
const struct iio_chan_spec *chan,
enum meson_sar_adc_avg_mode avg_mode,
enum meson_sar_adc_num_samples avg_samples,
int *val)
{
iio: adc: meson-saradc: add support for the chip's temperature sensor Channel 6 of the SAR ADC can be switched between two inputs: SAR_ADC_CH6 input (an actual pad on the SoC) and the signal from the temperature sensor inside the SoC. To get usable results from the temperature sensor we need to read the corresponding calibration data from the eFuse and pass it to the SAR ADC registers. If the temperature sensor is not calibrated (the eFuse data contains a bit for this) then the driver will only register the iio_chan_spec's for voltage measurements. This only enables the temperature sensor for the Meson8 SoC. Meson8b and Meson8m2 SoCs can be supported in the future as well but we first need a way to pass the fifth TSC (temperature sensor coefficient) bit to the HHI register area (apart from that the infrastructure as already implemented for Meson8 can be used). On the 64-bit SoCs (GXBB, GXL and GXM) the temperature sensor inside SAR ADC is firmware-controlled (by BL30, we can simply use the SCPI hwmon driver to get the chip temperature). To keep the devicetree interface backwards compatible we simply skip the temperature sensor initialization if no eFuse nvmem cell is passed via devicetree. The public documentation for the SAR ADC IP block does not explain how to use the registers to read the temperature. The logic from this patch is based on reading and understanding Amlogic's GPL kernel sources. Signed-off-by: Martin Blumenstingl <martin.blumenstingl@googlemail.com> Signed-off-by: Jonathan Cameron <Jonathan.Cameron@huawei.com>
2018-11-04 07:10:24 +08:00
struct meson_sar_adc_priv *priv = iio_priv(indio_dev);
struct device *dev = indio_dev->dev.parent;
iio: adc: add a driver for the SAR ADC found in Amlogic Meson SoCs This adds support for the SAR (Successive Approximation Register) ADC on the Amlogic Meson SoCs. The code is based on the public S805 (Meson8b) and S905 (GXBB) datasheets (see [0] and [1]), as well as by reading (various versions of) the vendor driver and by inspecting the registers on the vendor kernels of my testing-hardware. Currently the GXBB, GXL and GXM SoCs are supported. GXBB hardware has 10-bit ADC resolution, while GXL and GXM have 12-bit ADC resolution. The code was written to support older SoCs (Meson8 and Meson8b) as well, but due to lack of actual testing-hardware no of_device_id was added for these. Two "features" from the vendor driver are currently missing: - the vendor driver uses channel #7 for calibration (this improves the accuracy of the results - in my tests the results were less than 3% off without calibration compared to the vendor driver). Adding support for this should be easy, but is not required for most applications. - channel #6 is connected to the SoCs internal temperature sensor. Adding support for this is probably not so easy since (based on the u-boot sources) most SoC versions are using different registers and algorithms for the conversion from "ADC value" to temperature. Supported by the hardware but currently not supported by the driver: - reading multiple channels at the same time (the hardware has a FIFO buffer which stores multiple results) - continuous sampling (this would require a way to enable this individually because otherwise the ADC would be drawing power constantly) - interrupt support (similar to the vendor driver this new driver is polling the results. It is unclear if the IRQ-mode is supported on older (Meson6 or Meson8) hardware as well or if there are any errata) [0] http://dn.odroid.com/S805/Datasheet/S805_Datasheet%20V0.8%2020150126.pdf [1] http://dn.odroid.com/S905/DataSheet/S905_Public_Datasheet_V1.1.4.pdf Signed-off-by: Martin Blumenstingl <martin.blumenstingl@googlemail.com> Tested-by: Neil Armstrong <narmstrong@baylibre.com> Signed-off-by: Jonathan Cameron <jic23@kernel.org>
2017-01-23 02:17:13 +08:00
int ret;
iio: adc: meson-saradc: add support for the chip's temperature sensor Channel 6 of the SAR ADC can be switched between two inputs: SAR_ADC_CH6 input (an actual pad on the SoC) and the signal from the temperature sensor inside the SoC. To get usable results from the temperature sensor we need to read the corresponding calibration data from the eFuse and pass it to the SAR ADC registers. If the temperature sensor is not calibrated (the eFuse data contains a bit for this) then the driver will only register the iio_chan_spec's for voltage measurements. This only enables the temperature sensor for the Meson8 SoC. Meson8b and Meson8m2 SoCs can be supported in the future as well but we first need a way to pass the fifth TSC (temperature sensor coefficient) bit to the HHI register area (apart from that the infrastructure as already implemented for Meson8 can be used). On the 64-bit SoCs (GXBB, GXL and GXM) the temperature sensor inside SAR ADC is firmware-controlled (by BL30, we can simply use the SCPI hwmon driver to get the chip temperature). To keep the devicetree interface backwards compatible we simply skip the temperature sensor initialization if no eFuse nvmem cell is passed via devicetree. The public documentation for the SAR ADC IP block does not explain how to use the registers to read the temperature. The logic from this patch is based on reading and understanding Amlogic's GPL kernel sources. Signed-off-by: Martin Blumenstingl <martin.blumenstingl@googlemail.com> Signed-off-by: Jonathan Cameron <Jonathan.Cameron@huawei.com>
2018-11-04 07:10:24 +08:00
if (chan->type == IIO_TEMP && !priv->temperature_sensor_calibrated)
return -ENOTSUPP;
iio: adc: add a driver for the SAR ADC found in Amlogic Meson SoCs This adds support for the SAR (Successive Approximation Register) ADC on the Amlogic Meson SoCs. The code is based on the public S805 (Meson8b) and S905 (GXBB) datasheets (see [0] and [1]), as well as by reading (various versions of) the vendor driver and by inspecting the registers on the vendor kernels of my testing-hardware. Currently the GXBB, GXL and GXM SoCs are supported. GXBB hardware has 10-bit ADC resolution, while GXL and GXM have 12-bit ADC resolution. The code was written to support older SoCs (Meson8 and Meson8b) as well, but due to lack of actual testing-hardware no of_device_id was added for these. Two "features" from the vendor driver are currently missing: - the vendor driver uses channel #7 for calibration (this improves the accuracy of the results - in my tests the results were less than 3% off without calibration compared to the vendor driver). Adding support for this should be easy, but is not required for most applications. - channel #6 is connected to the SoCs internal temperature sensor. Adding support for this is probably not so easy since (based on the u-boot sources) most SoC versions are using different registers and algorithms for the conversion from "ADC value" to temperature. Supported by the hardware but currently not supported by the driver: - reading multiple channels at the same time (the hardware has a FIFO buffer which stores multiple results) - continuous sampling (this would require a way to enable this individually because otherwise the ADC would be drawing power constantly) - interrupt support (similar to the vendor driver this new driver is polling the results. It is unclear if the IRQ-mode is supported on older (Meson6 or Meson8) hardware as well or if there are any errata) [0] http://dn.odroid.com/S805/Datasheet/S805_Datasheet%20V0.8%2020150126.pdf [1] http://dn.odroid.com/S905/DataSheet/S905_Public_Datasheet_V1.1.4.pdf Signed-off-by: Martin Blumenstingl <martin.blumenstingl@googlemail.com> Tested-by: Neil Armstrong <narmstrong@baylibre.com> Signed-off-by: Jonathan Cameron <jic23@kernel.org>
2017-01-23 02:17:13 +08:00
ret = meson_sar_adc_lock(indio_dev);
if (ret)
return ret;
/* clear the FIFO to make sure we're not reading old values */
meson_sar_adc_clear_fifo(indio_dev);
meson_sar_adc_set_averaging(indio_dev, chan, avg_mode, avg_samples);
meson_sar_adc_enable_channel(indio_dev, chan);
meson_sar_adc_start_sample_engine(indio_dev);
ret = meson_sar_adc_read_raw_sample(indio_dev, chan, val);
meson_sar_adc_stop_sample_engine(indio_dev);
meson_sar_adc_unlock(indio_dev);
if (ret) {
dev_warn(dev, "failed to read sample for channel %lu: %d\n",
chan->address, ret);
iio: adc: add a driver for the SAR ADC found in Amlogic Meson SoCs This adds support for the SAR (Successive Approximation Register) ADC on the Amlogic Meson SoCs. The code is based on the public S805 (Meson8b) and S905 (GXBB) datasheets (see [0] and [1]), as well as by reading (various versions of) the vendor driver and by inspecting the registers on the vendor kernels of my testing-hardware. Currently the GXBB, GXL and GXM SoCs are supported. GXBB hardware has 10-bit ADC resolution, while GXL and GXM have 12-bit ADC resolution. The code was written to support older SoCs (Meson8 and Meson8b) as well, but due to lack of actual testing-hardware no of_device_id was added for these. Two "features" from the vendor driver are currently missing: - the vendor driver uses channel #7 for calibration (this improves the accuracy of the results - in my tests the results were less than 3% off without calibration compared to the vendor driver). Adding support for this should be easy, but is not required for most applications. - channel #6 is connected to the SoCs internal temperature sensor. Adding support for this is probably not so easy since (based on the u-boot sources) most SoC versions are using different registers and algorithms for the conversion from "ADC value" to temperature. Supported by the hardware but currently not supported by the driver: - reading multiple channels at the same time (the hardware has a FIFO buffer which stores multiple results) - continuous sampling (this would require a way to enable this individually because otherwise the ADC would be drawing power constantly) - interrupt support (similar to the vendor driver this new driver is polling the results. It is unclear if the IRQ-mode is supported on older (Meson6 or Meson8) hardware as well or if there are any errata) [0] http://dn.odroid.com/S805/Datasheet/S805_Datasheet%20V0.8%2020150126.pdf [1] http://dn.odroid.com/S905/DataSheet/S905_Public_Datasheet_V1.1.4.pdf Signed-off-by: Martin Blumenstingl <martin.blumenstingl@googlemail.com> Tested-by: Neil Armstrong <narmstrong@baylibre.com> Signed-off-by: Jonathan Cameron <jic23@kernel.org>
2017-01-23 02:17:13 +08:00
return ret;
}
return IIO_VAL_INT;
}
static int meson_sar_adc_iio_info_read_raw(struct iio_dev *indio_dev,
const struct iio_chan_spec *chan,
int *val, int *val2, long mask)
{
struct meson_sar_adc_priv *priv = iio_priv(indio_dev);
struct device *dev = indio_dev->dev.parent;
iio: adc: add a driver for the SAR ADC found in Amlogic Meson SoCs This adds support for the SAR (Successive Approximation Register) ADC on the Amlogic Meson SoCs. The code is based on the public S805 (Meson8b) and S905 (GXBB) datasheets (see [0] and [1]), as well as by reading (various versions of) the vendor driver and by inspecting the registers on the vendor kernels of my testing-hardware. Currently the GXBB, GXL and GXM SoCs are supported. GXBB hardware has 10-bit ADC resolution, while GXL and GXM have 12-bit ADC resolution. The code was written to support older SoCs (Meson8 and Meson8b) as well, but due to lack of actual testing-hardware no of_device_id was added for these. Two "features" from the vendor driver are currently missing: - the vendor driver uses channel #7 for calibration (this improves the accuracy of the results - in my tests the results were less than 3% off without calibration compared to the vendor driver). Adding support for this should be easy, but is not required for most applications. - channel #6 is connected to the SoCs internal temperature sensor. Adding support for this is probably not so easy since (based on the u-boot sources) most SoC versions are using different registers and algorithms for the conversion from "ADC value" to temperature. Supported by the hardware but currently not supported by the driver: - reading multiple channels at the same time (the hardware has a FIFO buffer which stores multiple results) - continuous sampling (this would require a way to enable this individually because otherwise the ADC would be drawing power constantly) - interrupt support (similar to the vendor driver this new driver is polling the results. It is unclear if the IRQ-mode is supported on older (Meson6 or Meson8) hardware as well or if there are any errata) [0] http://dn.odroid.com/S805/Datasheet/S805_Datasheet%20V0.8%2020150126.pdf [1] http://dn.odroid.com/S905/DataSheet/S905_Public_Datasheet_V1.1.4.pdf Signed-off-by: Martin Blumenstingl <martin.blumenstingl@googlemail.com> Tested-by: Neil Armstrong <narmstrong@baylibre.com> Signed-off-by: Jonathan Cameron <jic23@kernel.org>
2017-01-23 02:17:13 +08:00
int ret;
switch (mask) {
case IIO_CHAN_INFO_RAW:
return meson_sar_adc_get_sample(indio_dev, chan, NO_AVERAGING,
ONE_SAMPLE, val);
case IIO_CHAN_INFO_AVERAGE_RAW:
return meson_sar_adc_get_sample(indio_dev, chan,
MEAN_AVERAGING, EIGHT_SAMPLES,
val);
case IIO_CHAN_INFO_SCALE:
iio: adc: meson-saradc: add support for the chip's temperature sensor Channel 6 of the SAR ADC can be switched between two inputs: SAR_ADC_CH6 input (an actual pad on the SoC) and the signal from the temperature sensor inside the SoC. To get usable results from the temperature sensor we need to read the corresponding calibration data from the eFuse and pass it to the SAR ADC registers. If the temperature sensor is not calibrated (the eFuse data contains a bit for this) then the driver will only register the iio_chan_spec's for voltage measurements. This only enables the temperature sensor for the Meson8 SoC. Meson8b and Meson8m2 SoCs can be supported in the future as well but we first need a way to pass the fifth TSC (temperature sensor coefficient) bit to the HHI register area (apart from that the infrastructure as already implemented for Meson8 can be used). On the 64-bit SoCs (GXBB, GXL and GXM) the temperature sensor inside SAR ADC is firmware-controlled (by BL30, we can simply use the SCPI hwmon driver to get the chip temperature). To keep the devicetree interface backwards compatible we simply skip the temperature sensor initialization if no eFuse nvmem cell is passed via devicetree. The public documentation for the SAR ADC IP block does not explain how to use the registers to read the temperature. The logic from this patch is based on reading and understanding Amlogic's GPL kernel sources. Signed-off-by: Martin Blumenstingl <martin.blumenstingl@googlemail.com> Signed-off-by: Jonathan Cameron <Jonathan.Cameron@huawei.com>
2018-11-04 07:10:24 +08:00
if (chan->type == IIO_VOLTAGE) {
ret = regulator_get_voltage(priv->vref);
if (ret < 0) {
dev_err(dev, "failed to get vref voltage: %d\n", ret);
iio: adc: meson-saradc: add support for the chip's temperature sensor Channel 6 of the SAR ADC can be switched between two inputs: SAR_ADC_CH6 input (an actual pad on the SoC) and the signal from the temperature sensor inside the SoC. To get usable results from the temperature sensor we need to read the corresponding calibration data from the eFuse and pass it to the SAR ADC registers. If the temperature sensor is not calibrated (the eFuse data contains a bit for this) then the driver will only register the iio_chan_spec's for voltage measurements. This only enables the temperature sensor for the Meson8 SoC. Meson8b and Meson8m2 SoCs can be supported in the future as well but we first need a way to pass the fifth TSC (temperature sensor coefficient) bit to the HHI register area (apart from that the infrastructure as already implemented for Meson8 can be used). On the 64-bit SoCs (GXBB, GXL and GXM) the temperature sensor inside SAR ADC is firmware-controlled (by BL30, we can simply use the SCPI hwmon driver to get the chip temperature). To keep the devicetree interface backwards compatible we simply skip the temperature sensor initialization if no eFuse nvmem cell is passed via devicetree. The public documentation for the SAR ADC IP block does not explain how to use the registers to read the temperature. The logic from this patch is based on reading and understanding Amlogic's GPL kernel sources. Signed-off-by: Martin Blumenstingl <martin.blumenstingl@googlemail.com> Signed-off-by: Jonathan Cameron <Jonathan.Cameron@huawei.com>
2018-11-04 07:10:24 +08:00
return ret;
}
*val = ret / 1000;
*val2 = priv->param->resolution;
return IIO_VAL_FRACTIONAL_LOG2;
} else if (chan->type == IIO_TEMP) {
/* SoC specific multiplier and divider */
*val = priv->param->temperature_multiplier;
*val2 = priv->param->temperature_divider;
/* celsius to millicelsius */
*val *= 1000;
return IIO_VAL_FRACTIONAL;
} else {
return -EINVAL;
iio: adc: add a driver for the SAR ADC found in Amlogic Meson SoCs This adds support for the SAR (Successive Approximation Register) ADC on the Amlogic Meson SoCs. The code is based on the public S805 (Meson8b) and S905 (GXBB) datasheets (see [0] and [1]), as well as by reading (various versions of) the vendor driver and by inspecting the registers on the vendor kernels of my testing-hardware. Currently the GXBB, GXL and GXM SoCs are supported. GXBB hardware has 10-bit ADC resolution, while GXL and GXM have 12-bit ADC resolution. The code was written to support older SoCs (Meson8 and Meson8b) as well, but due to lack of actual testing-hardware no of_device_id was added for these. Two "features" from the vendor driver are currently missing: - the vendor driver uses channel #7 for calibration (this improves the accuracy of the results - in my tests the results were less than 3% off without calibration compared to the vendor driver). Adding support for this should be easy, but is not required for most applications. - channel #6 is connected to the SoCs internal temperature sensor. Adding support for this is probably not so easy since (based on the u-boot sources) most SoC versions are using different registers and algorithms for the conversion from "ADC value" to temperature. Supported by the hardware but currently not supported by the driver: - reading multiple channels at the same time (the hardware has a FIFO buffer which stores multiple results) - continuous sampling (this would require a way to enable this individually because otherwise the ADC would be drawing power constantly) - interrupt support (similar to the vendor driver this new driver is polling the results. It is unclear if the IRQ-mode is supported on older (Meson6 or Meson8) hardware as well or if there are any errata) [0] http://dn.odroid.com/S805/Datasheet/S805_Datasheet%20V0.8%2020150126.pdf [1] http://dn.odroid.com/S905/DataSheet/S905_Public_Datasheet_V1.1.4.pdf Signed-off-by: Martin Blumenstingl <martin.blumenstingl@googlemail.com> Tested-by: Neil Armstrong <narmstrong@baylibre.com> Signed-off-by: Jonathan Cameron <jic23@kernel.org>
2017-01-23 02:17:13 +08:00
}
case IIO_CHAN_INFO_CALIBBIAS:
*val = priv->calibbias;
return IIO_VAL_INT;
case IIO_CHAN_INFO_CALIBSCALE:
*val = priv->calibscale / MILLION;
*val2 = priv->calibscale % MILLION;
return IIO_VAL_INT_PLUS_MICRO;
iio: adc: meson-saradc: add support for the chip's temperature sensor Channel 6 of the SAR ADC can be switched between two inputs: SAR_ADC_CH6 input (an actual pad on the SoC) and the signal from the temperature sensor inside the SoC. To get usable results from the temperature sensor we need to read the corresponding calibration data from the eFuse and pass it to the SAR ADC registers. If the temperature sensor is not calibrated (the eFuse data contains a bit for this) then the driver will only register the iio_chan_spec's for voltage measurements. This only enables the temperature sensor for the Meson8 SoC. Meson8b and Meson8m2 SoCs can be supported in the future as well but we first need a way to pass the fifth TSC (temperature sensor coefficient) bit to the HHI register area (apart from that the infrastructure as already implemented for Meson8 can be used). On the 64-bit SoCs (GXBB, GXL and GXM) the temperature sensor inside SAR ADC is firmware-controlled (by BL30, we can simply use the SCPI hwmon driver to get the chip temperature). To keep the devicetree interface backwards compatible we simply skip the temperature sensor initialization if no eFuse nvmem cell is passed via devicetree. The public documentation for the SAR ADC IP block does not explain how to use the registers to read the temperature. The logic from this patch is based on reading and understanding Amlogic's GPL kernel sources. Signed-off-by: Martin Blumenstingl <martin.blumenstingl@googlemail.com> Signed-off-by: Jonathan Cameron <Jonathan.Cameron@huawei.com>
2018-11-04 07:10:24 +08:00
case IIO_CHAN_INFO_OFFSET:
*val = DIV_ROUND_CLOSEST(MESON_SAR_ADC_TEMP_OFFSET *
priv->param->temperature_divider,
priv->param->temperature_multiplier);
*val -= priv->temperature_sensor_adc_val;
return IIO_VAL_INT;
iio: adc: add a driver for the SAR ADC found in Amlogic Meson SoCs This adds support for the SAR (Successive Approximation Register) ADC on the Amlogic Meson SoCs. The code is based on the public S805 (Meson8b) and S905 (GXBB) datasheets (see [0] and [1]), as well as by reading (various versions of) the vendor driver and by inspecting the registers on the vendor kernels of my testing-hardware. Currently the GXBB, GXL and GXM SoCs are supported. GXBB hardware has 10-bit ADC resolution, while GXL and GXM have 12-bit ADC resolution. The code was written to support older SoCs (Meson8 and Meson8b) as well, but due to lack of actual testing-hardware no of_device_id was added for these. Two "features" from the vendor driver are currently missing: - the vendor driver uses channel #7 for calibration (this improves the accuracy of the results - in my tests the results were less than 3% off without calibration compared to the vendor driver). Adding support for this should be easy, but is not required for most applications. - channel #6 is connected to the SoCs internal temperature sensor. Adding support for this is probably not so easy since (based on the u-boot sources) most SoC versions are using different registers and algorithms for the conversion from "ADC value" to temperature. Supported by the hardware but currently not supported by the driver: - reading multiple channels at the same time (the hardware has a FIFO buffer which stores multiple results) - continuous sampling (this would require a way to enable this individually because otherwise the ADC would be drawing power constantly) - interrupt support (similar to the vendor driver this new driver is polling the results. It is unclear if the IRQ-mode is supported on older (Meson6 or Meson8) hardware as well or if there are any errata) [0] http://dn.odroid.com/S805/Datasheet/S805_Datasheet%20V0.8%2020150126.pdf [1] http://dn.odroid.com/S905/DataSheet/S905_Public_Datasheet_V1.1.4.pdf Signed-off-by: Martin Blumenstingl <martin.blumenstingl@googlemail.com> Tested-by: Neil Armstrong <narmstrong@baylibre.com> Signed-off-by: Jonathan Cameron <jic23@kernel.org>
2017-01-23 02:17:13 +08:00
default:
return -EINVAL;
}
}
static int meson_sar_adc_clk_init(struct iio_dev *indio_dev,
void __iomem *base)
{
struct meson_sar_adc_priv *priv = iio_priv(indio_dev);
struct device *dev = indio_dev->dev.parent;
iio: adc: add a driver for the SAR ADC found in Amlogic Meson SoCs This adds support for the SAR (Successive Approximation Register) ADC on the Amlogic Meson SoCs. The code is based on the public S805 (Meson8b) and S905 (GXBB) datasheets (see [0] and [1]), as well as by reading (various versions of) the vendor driver and by inspecting the registers on the vendor kernels of my testing-hardware. Currently the GXBB, GXL and GXM SoCs are supported. GXBB hardware has 10-bit ADC resolution, while GXL and GXM have 12-bit ADC resolution. The code was written to support older SoCs (Meson8 and Meson8b) as well, but due to lack of actual testing-hardware no of_device_id was added for these. Two "features" from the vendor driver are currently missing: - the vendor driver uses channel #7 for calibration (this improves the accuracy of the results - in my tests the results were less than 3% off without calibration compared to the vendor driver). Adding support for this should be easy, but is not required for most applications. - channel #6 is connected to the SoCs internal temperature sensor. Adding support for this is probably not so easy since (based on the u-boot sources) most SoC versions are using different registers and algorithms for the conversion from "ADC value" to temperature. Supported by the hardware but currently not supported by the driver: - reading multiple channels at the same time (the hardware has a FIFO buffer which stores multiple results) - continuous sampling (this would require a way to enable this individually because otherwise the ADC would be drawing power constantly) - interrupt support (similar to the vendor driver this new driver is polling the results. It is unclear if the IRQ-mode is supported on older (Meson6 or Meson8) hardware as well or if there are any errata) [0] http://dn.odroid.com/S805/Datasheet/S805_Datasheet%20V0.8%2020150126.pdf [1] http://dn.odroid.com/S905/DataSheet/S905_Public_Datasheet_V1.1.4.pdf Signed-off-by: Martin Blumenstingl <martin.blumenstingl@googlemail.com> Tested-by: Neil Armstrong <narmstrong@baylibre.com> Signed-off-by: Jonathan Cameron <jic23@kernel.org>
2017-01-23 02:17:13 +08:00
struct clk_init_data init;
const char *clk_parents[1];
init.name = devm_kasprintf(dev, GFP_KERNEL, "%s#adc_div", dev_name(dev));
if (!init.name)
return -ENOMEM;
iio: adc: add a driver for the SAR ADC found in Amlogic Meson SoCs This adds support for the SAR (Successive Approximation Register) ADC on the Amlogic Meson SoCs. The code is based on the public S805 (Meson8b) and S905 (GXBB) datasheets (see [0] and [1]), as well as by reading (various versions of) the vendor driver and by inspecting the registers on the vendor kernels of my testing-hardware. Currently the GXBB, GXL and GXM SoCs are supported. GXBB hardware has 10-bit ADC resolution, while GXL and GXM have 12-bit ADC resolution. The code was written to support older SoCs (Meson8 and Meson8b) as well, but due to lack of actual testing-hardware no of_device_id was added for these. Two "features" from the vendor driver are currently missing: - the vendor driver uses channel #7 for calibration (this improves the accuracy of the results - in my tests the results were less than 3% off without calibration compared to the vendor driver). Adding support for this should be easy, but is not required for most applications. - channel #6 is connected to the SoCs internal temperature sensor. Adding support for this is probably not so easy since (based on the u-boot sources) most SoC versions are using different registers and algorithms for the conversion from "ADC value" to temperature. Supported by the hardware but currently not supported by the driver: - reading multiple channels at the same time (the hardware has a FIFO buffer which stores multiple results) - continuous sampling (this would require a way to enable this individually because otherwise the ADC would be drawing power constantly) - interrupt support (similar to the vendor driver this new driver is polling the results. It is unclear if the IRQ-mode is supported on older (Meson6 or Meson8) hardware as well or if there are any errata) [0] http://dn.odroid.com/S805/Datasheet/S805_Datasheet%20V0.8%2020150126.pdf [1] http://dn.odroid.com/S905/DataSheet/S905_Public_Datasheet_V1.1.4.pdf Signed-off-by: Martin Blumenstingl <martin.blumenstingl@googlemail.com> Tested-by: Neil Armstrong <narmstrong@baylibre.com> Signed-off-by: Jonathan Cameron <jic23@kernel.org>
2017-01-23 02:17:13 +08:00
init.flags = 0;
init.ops = &clk_divider_ops;
clk_parents[0] = __clk_get_name(priv->clkin);
init.parent_names = clk_parents;
init.num_parents = 1;
priv->clk_div.reg = base + MESON_SAR_ADC_REG3;
priv->clk_div.shift = MESON_SAR_ADC_REG3_ADC_CLK_DIV_SHIFT;
priv->clk_div.width = MESON_SAR_ADC_REG3_ADC_CLK_DIV_WIDTH;
priv->clk_div.hw.init = &init;
priv->clk_div.flags = 0;
priv->adc_div_clk = devm_clk_register(dev, &priv->clk_div.hw);
iio: adc: add a driver for the SAR ADC found in Amlogic Meson SoCs This adds support for the SAR (Successive Approximation Register) ADC on the Amlogic Meson SoCs. The code is based on the public S805 (Meson8b) and S905 (GXBB) datasheets (see [0] and [1]), as well as by reading (various versions of) the vendor driver and by inspecting the registers on the vendor kernels of my testing-hardware. Currently the GXBB, GXL and GXM SoCs are supported. GXBB hardware has 10-bit ADC resolution, while GXL and GXM have 12-bit ADC resolution. The code was written to support older SoCs (Meson8 and Meson8b) as well, but due to lack of actual testing-hardware no of_device_id was added for these. Two "features" from the vendor driver are currently missing: - the vendor driver uses channel #7 for calibration (this improves the accuracy of the results - in my tests the results were less than 3% off without calibration compared to the vendor driver). Adding support for this should be easy, but is not required for most applications. - channel #6 is connected to the SoCs internal temperature sensor. Adding support for this is probably not so easy since (based on the u-boot sources) most SoC versions are using different registers and algorithms for the conversion from "ADC value" to temperature. Supported by the hardware but currently not supported by the driver: - reading multiple channels at the same time (the hardware has a FIFO buffer which stores multiple results) - continuous sampling (this would require a way to enable this individually because otherwise the ADC would be drawing power constantly) - interrupt support (similar to the vendor driver this new driver is polling the results. It is unclear if the IRQ-mode is supported on older (Meson6 or Meson8) hardware as well or if there are any errata) [0] http://dn.odroid.com/S805/Datasheet/S805_Datasheet%20V0.8%2020150126.pdf [1] http://dn.odroid.com/S905/DataSheet/S905_Public_Datasheet_V1.1.4.pdf Signed-off-by: Martin Blumenstingl <martin.blumenstingl@googlemail.com> Tested-by: Neil Armstrong <narmstrong@baylibre.com> Signed-off-by: Jonathan Cameron <jic23@kernel.org>
2017-01-23 02:17:13 +08:00
if (WARN_ON(IS_ERR(priv->adc_div_clk)))
return PTR_ERR(priv->adc_div_clk);
init.name = devm_kasprintf(dev, GFP_KERNEL, "%s#adc_en", dev_name(dev));
if (!init.name)
return -ENOMEM;
iio: adc: add a driver for the SAR ADC found in Amlogic Meson SoCs This adds support for the SAR (Successive Approximation Register) ADC on the Amlogic Meson SoCs. The code is based on the public S805 (Meson8b) and S905 (GXBB) datasheets (see [0] and [1]), as well as by reading (various versions of) the vendor driver and by inspecting the registers on the vendor kernels of my testing-hardware. Currently the GXBB, GXL and GXM SoCs are supported. GXBB hardware has 10-bit ADC resolution, while GXL and GXM have 12-bit ADC resolution. The code was written to support older SoCs (Meson8 and Meson8b) as well, but due to lack of actual testing-hardware no of_device_id was added for these. Two "features" from the vendor driver are currently missing: - the vendor driver uses channel #7 for calibration (this improves the accuracy of the results - in my tests the results were less than 3% off without calibration compared to the vendor driver). Adding support for this should be easy, but is not required for most applications. - channel #6 is connected to the SoCs internal temperature sensor. Adding support for this is probably not so easy since (based on the u-boot sources) most SoC versions are using different registers and algorithms for the conversion from "ADC value" to temperature. Supported by the hardware but currently not supported by the driver: - reading multiple channels at the same time (the hardware has a FIFO buffer which stores multiple results) - continuous sampling (this would require a way to enable this individually because otherwise the ADC would be drawing power constantly) - interrupt support (similar to the vendor driver this new driver is polling the results. It is unclear if the IRQ-mode is supported on older (Meson6 or Meson8) hardware as well or if there are any errata) [0] http://dn.odroid.com/S805/Datasheet/S805_Datasheet%20V0.8%2020150126.pdf [1] http://dn.odroid.com/S905/DataSheet/S905_Public_Datasheet_V1.1.4.pdf Signed-off-by: Martin Blumenstingl <martin.blumenstingl@googlemail.com> Tested-by: Neil Armstrong <narmstrong@baylibre.com> Signed-off-by: Jonathan Cameron <jic23@kernel.org>
2017-01-23 02:17:13 +08:00
init.flags = CLK_SET_RATE_PARENT;
init.ops = &clk_gate_ops;
clk_parents[0] = __clk_get_name(priv->adc_div_clk);
init.parent_names = clk_parents;
init.num_parents = 1;
priv->clk_gate.reg = base + MESON_SAR_ADC_REG3;
priv->clk_gate.bit_idx = __ffs(MESON_SAR_ADC_REG3_CLK_EN);
iio: adc: add a driver for the SAR ADC found in Amlogic Meson SoCs This adds support for the SAR (Successive Approximation Register) ADC on the Amlogic Meson SoCs. The code is based on the public S805 (Meson8b) and S905 (GXBB) datasheets (see [0] and [1]), as well as by reading (various versions of) the vendor driver and by inspecting the registers on the vendor kernels of my testing-hardware. Currently the GXBB, GXL and GXM SoCs are supported. GXBB hardware has 10-bit ADC resolution, while GXL and GXM have 12-bit ADC resolution. The code was written to support older SoCs (Meson8 and Meson8b) as well, but due to lack of actual testing-hardware no of_device_id was added for these. Two "features" from the vendor driver are currently missing: - the vendor driver uses channel #7 for calibration (this improves the accuracy of the results - in my tests the results were less than 3% off without calibration compared to the vendor driver). Adding support for this should be easy, but is not required for most applications. - channel #6 is connected to the SoCs internal temperature sensor. Adding support for this is probably not so easy since (based on the u-boot sources) most SoC versions are using different registers and algorithms for the conversion from "ADC value" to temperature. Supported by the hardware but currently not supported by the driver: - reading multiple channels at the same time (the hardware has a FIFO buffer which stores multiple results) - continuous sampling (this would require a way to enable this individually because otherwise the ADC would be drawing power constantly) - interrupt support (similar to the vendor driver this new driver is polling the results. It is unclear if the IRQ-mode is supported on older (Meson6 or Meson8) hardware as well or if there are any errata) [0] http://dn.odroid.com/S805/Datasheet/S805_Datasheet%20V0.8%2020150126.pdf [1] http://dn.odroid.com/S905/DataSheet/S905_Public_Datasheet_V1.1.4.pdf Signed-off-by: Martin Blumenstingl <martin.blumenstingl@googlemail.com> Tested-by: Neil Armstrong <narmstrong@baylibre.com> Signed-off-by: Jonathan Cameron <jic23@kernel.org>
2017-01-23 02:17:13 +08:00
priv->clk_gate.hw.init = &init;
priv->adc_clk = devm_clk_register(dev, &priv->clk_gate.hw);
iio: adc: add a driver for the SAR ADC found in Amlogic Meson SoCs This adds support for the SAR (Successive Approximation Register) ADC on the Amlogic Meson SoCs. The code is based on the public S805 (Meson8b) and S905 (GXBB) datasheets (see [0] and [1]), as well as by reading (various versions of) the vendor driver and by inspecting the registers on the vendor kernels of my testing-hardware. Currently the GXBB, GXL and GXM SoCs are supported. GXBB hardware has 10-bit ADC resolution, while GXL and GXM have 12-bit ADC resolution. The code was written to support older SoCs (Meson8 and Meson8b) as well, but due to lack of actual testing-hardware no of_device_id was added for these. Two "features" from the vendor driver are currently missing: - the vendor driver uses channel #7 for calibration (this improves the accuracy of the results - in my tests the results were less than 3% off without calibration compared to the vendor driver). Adding support for this should be easy, but is not required for most applications. - channel #6 is connected to the SoCs internal temperature sensor. Adding support for this is probably not so easy since (based on the u-boot sources) most SoC versions are using different registers and algorithms for the conversion from "ADC value" to temperature. Supported by the hardware but currently not supported by the driver: - reading multiple channels at the same time (the hardware has a FIFO buffer which stores multiple results) - continuous sampling (this would require a way to enable this individually because otherwise the ADC would be drawing power constantly) - interrupt support (similar to the vendor driver this new driver is polling the results. It is unclear if the IRQ-mode is supported on older (Meson6 or Meson8) hardware as well or if there are any errata) [0] http://dn.odroid.com/S805/Datasheet/S805_Datasheet%20V0.8%2020150126.pdf [1] http://dn.odroid.com/S905/DataSheet/S905_Public_Datasheet_V1.1.4.pdf Signed-off-by: Martin Blumenstingl <martin.blumenstingl@googlemail.com> Tested-by: Neil Armstrong <narmstrong@baylibre.com> Signed-off-by: Jonathan Cameron <jic23@kernel.org>
2017-01-23 02:17:13 +08:00
if (WARN_ON(IS_ERR(priv->adc_clk)))
return PTR_ERR(priv->adc_clk);
return 0;
}
iio: adc: meson-saradc: add support for the chip's temperature sensor Channel 6 of the SAR ADC can be switched between two inputs: SAR_ADC_CH6 input (an actual pad on the SoC) and the signal from the temperature sensor inside the SoC. To get usable results from the temperature sensor we need to read the corresponding calibration data from the eFuse and pass it to the SAR ADC registers. If the temperature sensor is not calibrated (the eFuse data contains a bit for this) then the driver will only register the iio_chan_spec's for voltage measurements. This only enables the temperature sensor for the Meson8 SoC. Meson8b and Meson8m2 SoCs can be supported in the future as well but we first need a way to pass the fifth TSC (temperature sensor coefficient) bit to the HHI register area (apart from that the infrastructure as already implemented for Meson8 can be used). On the 64-bit SoCs (GXBB, GXL and GXM) the temperature sensor inside SAR ADC is firmware-controlled (by BL30, we can simply use the SCPI hwmon driver to get the chip temperature). To keep the devicetree interface backwards compatible we simply skip the temperature sensor initialization if no eFuse nvmem cell is passed via devicetree. The public documentation for the SAR ADC IP block does not explain how to use the registers to read the temperature. The logic from this patch is based on reading and understanding Amlogic's GPL kernel sources. Signed-off-by: Martin Blumenstingl <martin.blumenstingl@googlemail.com> Signed-off-by: Jonathan Cameron <Jonathan.Cameron@huawei.com>
2018-11-04 07:10:24 +08:00
static int meson_sar_adc_temp_sensor_init(struct iio_dev *indio_dev)
{
struct meson_sar_adc_priv *priv = iio_priv(indio_dev);
u8 *buf, trimming_bits, trimming_mask, upper_adc_val;
struct device *dev = indio_dev->dev.parent;
iio: adc: meson-saradc: add support for the chip's temperature sensor Channel 6 of the SAR ADC can be switched between two inputs: SAR_ADC_CH6 input (an actual pad on the SoC) and the signal from the temperature sensor inside the SoC. To get usable results from the temperature sensor we need to read the corresponding calibration data from the eFuse and pass it to the SAR ADC registers. If the temperature sensor is not calibrated (the eFuse data contains a bit for this) then the driver will only register the iio_chan_spec's for voltage measurements. This only enables the temperature sensor for the Meson8 SoC. Meson8b and Meson8m2 SoCs can be supported in the future as well but we first need a way to pass the fifth TSC (temperature sensor coefficient) bit to the HHI register area (apart from that the infrastructure as already implemented for Meson8 can be used). On the 64-bit SoCs (GXBB, GXL and GXM) the temperature sensor inside SAR ADC is firmware-controlled (by BL30, we can simply use the SCPI hwmon driver to get the chip temperature). To keep the devicetree interface backwards compatible we simply skip the temperature sensor initialization if no eFuse nvmem cell is passed via devicetree. The public documentation for the SAR ADC IP block does not explain how to use the registers to read the temperature. The logic from this patch is based on reading and understanding Amlogic's GPL kernel sources. Signed-off-by: Martin Blumenstingl <martin.blumenstingl@googlemail.com> Signed-off-by: Jonathan Cameron <Jonathan.Cameron@huawei.com>
2018-11-04 07:10:24 +08:00
struct nvmem_cell *temperature_calib;
size_t read_len;
int ret;
temperature_calib = devm_nvmem_cell_get(dev, "temperature_calib");
iio: adc: meson-saradc: add support for the chip's temperature sensor Channel 6 of the SAR ADC can be switched between two inputs: SAR_ADC_CH6 input (an actual pad on the SoC) and the signal from the temperature sensor inside the SoC. To get usable results from the temperature sensor we need to read the corresponding calibration data from the eFuse and pass it to the SAR ADC registers. If the temperature sensor is not calibrated (the eFuse data contains a bit for this) then the driver will only register the iio_chan_spec's for voltage measurements. This only enables the temperature sensor for the Meson8 SoC. Meson8b and Meson8m2 SoCs can be supported in the future as well but we first need a way to pass the fifth TSC (temperature sensor coefficient) bit to the HHI register area (apart from that the infrastructure as already implemented for Meson8 can be used). On the 64-bit SoCs (GXBB, GXL and GXM) the temperature sensor inside SAR ADC is firmware-controlled (by BL30, we can simply use the SCPI hwmon driver to get the chip temperature). To keep the devicetree interface backwards compatible we simply skip the temperature sensor initialization if no eFuse nvmem cell is passed via devicetree. The public documentation for the SAR ADC IP block does not explain how to use the registers to read the temperature. The logic from this patch is based on reading and understanding Amlogic's GPL kernel sources. Signed-off-by: Martin Blumenstingl <martin.blumenstingl@googlemail.com> Signed-off-by: Jonathan Cameron <Jonathan.Cameron@huawei.com>
2018-11-04 07:10:24 +08:00
if (IS_ERR(temperature_calib)) {
ret = PTR_ERR(temperature_calib);
/*
* leave the temperature sensor disabled if no calibration data
* was passed via nvmem-cells.
*/
if (ret == -ENODEV)
return 0;
return dev_err_probe(dev, ret, "failed to get temperature_calib cell\n");
iio: adc: meson-saradc: add support for the chip's temperature sensor Channel 6 of the SAR ADC can be switched between two inputs: SAR_ADC_CH6 input (an actual pad on the SoC) and the signal from the temperature sensor inside the SoC. To get usable results from the temperature sensor we need to read the corresponding calibration data from the eFuse and pass it to the SAR ADC registers. If the temperature sensor is not calibrated (the eFuse data contains a bit for this) then the driver will only register the iio_chan_spec's for voltage measurements. This only enables the temperature sensor for the Meson8 SoC. Meson8b and Meson8m2 SoCs can be supported in the future as well but we first need a way to pass the fifth TSC (temperature sensor coefficient) bit to the HHI register area (apart from that the infrastructure as already implemented for Meson8 can be used). On the 64-bit SoCs (GXBB, GXL and GXM) the temperature sensor inside SAR ADC is firmware-controlled (by BL30, we can simply use the SCPI hwmon driver to get the chip temperature). To keep the devicetree interface backwards compatible we simply skip the temperature sensor initialization if no eFuse nvmem cell is passed via devicetree. The public documentation for the SAR ADC IP block does not explain how to use the registers to read the temperature. The logic from this patch is based on reading and understanding Amlogic's GPL kernel sources. Signed-off-by: Martin Blumenstingl <martin.blumenstingl@googlemail.com> Signed-off-by: Jonathan Cameron <Jonathan.Cameron@huawei.com>
2018-11-04 07:10:24 +08:00
}
priv->tsc_regmap = syscon_regmap_lookup_by_phandle(dev->of_node, "amlogic,hhi-sysctrl");
if (IS_ERR(priv->tsc_regmap))
return dev_err_probe(dev, PTR_ERR(priv->tsc_regmap),
"failed to get amlogic,hhi-sysctrl regmap\n");
iio: adc: meson-saradc: add support for the chip's temperature sensor Channel 6 of the SAR ADC can be switched between two inputs: SAR_ADC_CH6 input (an actual pad on the SoC) and the signal from the temperature sensor inside the SoC. To get usable results from the temperature sensor we need to read the corresponding calibration data from the eFuse and pass it to the SAR ADC registers. If the temperature sensor is not calibrated (the eFuse data contains a bit for this) then the driver will only register the iio_chan_spec's for voltage measurements. This only enables the temperature sensor for the Meson8 SoC. Meson8b and Meson8m2 SoCs can be supported in the future as well but we first need a way to pass the fifth TSC (temperature sensor coefficient) bit to the HHI register area (apart from that the infrastructure as already implemented for Meson8 can be used). On the 64-bit SoCs (GXBB, GXL and GXM) the temperature sensor inside SAR ADC is firmware-controlled (by BL30, we can simply use the SCPI hwmon driver to get the chip temperature). To keep the devicetree interface backwards compatible we simply skip the temperature sensor initialization if no eFuse nvmem cell is passed via devicetree. The public documentation for the SAR ADC IP block does not explain how to use the registers to read the temperature. The logic from this patch is based on reading and understanding Amlogic's GPL kernel sources. Signed-off-by: Martin Blumenstingl <martin.blumenstingl@googlemail.com> Signed-off-by: Jonathan Cameron <Jonathan.Cameron@huawei.com>
2018-11-04 07:10:24 +08:00
read_len = MESON_SAR_ADC_EFUSE_BYTES;
buf = nvmem_cell_read(temperature_calib, &read_len);
if (IS_ERR(buf))
return dev_err_probe(dev, PTR_ERR(buf), "failed to read temperature_calib cell\n");
if (read_len != MESON_SAR_ADC_EFUSE_BYTES) {
iio: adc: meson-saradc: add support for the chip's temperature sensor Channel 6 of the SAR ADC can be switched between two inputs: SAR_ADC_CH6 input (an actual pad on the SoC) and the signal from the temperature sensor inside the SoC. To get usable results from the temperature sensor we need to read the corresponding calibration data from the eFuse and pass it to the SAR ADC registers. If the temperature sensor is not calibrated (the eFuse data contains a bit for this) then the driver will only register the iio_chan_spec's for voltage measurements. This only enables the temperature sensor for the Meson8 SoC. Meson8b and Meson8m2 SoCs can be supported in the future as well but we first need a way to pass the fifth TSC (temperature sensor coefficient) bit to the HHI register area (apart from that the infrastructure as already implemented for Meson8 can be used). On the 64-bit SoCs (GXBB, GXL and GXM) the temperature sensor inside SAR ADC is firmware-controlled (by BL30, we can simply use the SCPI hwmon driver to get the chip temperature). To keep the devicetree interface backwards compatible we simply skip the temperature sensor initialization if no eFuse nvmem cell is passed via devicetree. The public documentation for the SAR ADC IP block does not explain how to use the registers to read the temperature. The logic from this patch is based on reading and understanding Amlogic's GPL kernel sources. Signed-off-by: Martin Blumenstingl <martin.blumenstingl@googlemail.com> Signed-off-by: Jonathan Cameron <Jonathan.Cameron@huawei.com>
2018-11-04 07:10:24 +08:00
kfree(buf);
return dev_err_probe(dev, -EINVAL, "invalid read size of temperature_calib cell\n");
iio: adc: meson-saradc: add support for the chip's temperature sensor Channel 6 of the SAR ADC can be switched between two inputs: SAR_ADC_CH6 input (an actual pad on the SoC) and the signal from the temperature sensor inside the SoC. To get usable results from the temperature sensor we need to read the corresponding calibration data from the eFuse and pass it to the SAR ADC registers. If the temperature sensor is not calibrated (the eFuse data contains a bit for this) then the driver will only register the iio_chan_spec's for voltage measurements. This only enables the temperature sensor for the Meson8 SoC. Meson8b and Meson8m2 SoCs can be supported in the future as well but we first need a way to pass the fifth TSC (temperature sensor coefficient) bit to the HHI register area (apart from that the infrastructure as already implemented for Meson8 can be used). On the 64-bit SoCs (GXBB, GXL and GXM) the temperature sensor inside SAR ADC is firmware-controlled (by BL30, we can simply use the SCPI hwmon driver to get the chip temperature). To keep the devicetree interface backwards compatible we simply skip the temperature sensor initialization if no eFuse nvmem cell is passed via devicetree. The public documentation for the SAR ADC IP block does not explain how to use the registers to read the temperature. The logic from this patch is based on reading and understanding Amlogic's GPL kernel sources. Signed-off-by: Martin Blumenstingl <martin.blumenstingl@googlemail.com> Signed-off-by: Jonathan Cameron <Jonathan.Cameron@huawei.com>
2018-11-04 07:10:24 +08:00
}
trimming_bits = priv->param->temperature_trimming_bits;
trimming_mask = BIT(trimming_bits) - 1;
priv->temperature_sensor_calibrated =
buf[3] & MESON_SAR_ADC_EFUSE_BYTE3_IS_CALIBRATED;
priv->temperature_sensor_coefficient = buf[2] & trimming_mask;
upper_adc_val = FIELD_GET(MESON_SAR_ADC_EFUSE_BYTE3_UPPER_ADC_VAL,
buf[3]);
priv->temperature_sensor_adc_val = buf[2];
priv->temperature_sensor_adc_val |= upper_adc_val << BITS_PER_BYTE;
priv->temperature_sensor_adc_val >>= trimming_bits;
kfree(buf);
return 0;
}
iio: adc: add a driver for the SAR ADC found in Amlogic Meson SoCs This adds support for the SAR (Successive Approximation Register) ADC on the Amlogic Meson SoCs. The code is based on the public S805 (Meson8b) and S905 (GXBB) datasheets (see [0] and [1]), as well as by reading (various versions of) the vendor driver and by inspecting the registers on the vendor kernels of my testing-hardware. Currently the GXBB, GXL and GXM SoCs are supported. GXBB hardware has 10-bit ADC resolution, while GXL and GXM have 12-bit ADC resolution. The code was written to support older SoCs (Meson8 and Meson8b) as well, but due to lack of actual testing-hardware no of_device_id was added for these. Two "features" from the vendor driver are currently missing: - the vendor driver uses channel #7 for calibration (this improves the accuracy of the results - in my tests the results were less than 3% off without calibration compared to the vendor driver). Adding support for this should be easy, but is not required for most applications. - channel #6 is connected to the SoCs internal temperature sensor. Adding support for this is probably not so easy since (based on the u-boot sources) most SoC versions are using different registers and algorithms for the conversion from "ADC value" to temperature. Supported by the hardware but currently not supported by the driver: - reading multiple channels at the same time (the hardware has a FIFO buffer which stores multiple results) - continuous sampling (this would require a way to enable this individually because otherwise the ADC would be drawing power constantly) - interrupt support (similar to the vendor driver this new driver is polling the results. It is unclear if the IRQ-mode is supported on older (Meson6 or Meson8) hardware as well or if there are any errata) [0] http://dn.odroid.com/S805/Datasheet/S805_Datasheet%20V0.8%2020150126.pdf [1] http://dn.odroid.com/S905/DataSheet/S905_Public_Datasheet_V1.1.4.pdf Signed-off-by: Martin Blumenstingl <martin.blumenstingl@googlemail.com> Tested-by: Neil Armstrong <narmstrong@baylibre.com> Signed-off-by: Jonathan Cameron <jic23@kernel.org>
2017-01-23 02:17:13 +08:00
static int meson_sar_adc_init(struct iio_dev *indio_dev)
{
struct meson_sar_adc_priv *priv = iio_priv(indio_dev);
struct device *dev = indio_dev->dev.parent;
int regval, i, ret;
iio: adc: add a driver for the SAR ADC found in Amlogic Meson SoCs This adds support for the SAR (Successive Approximation Register) ADC on the Amlogic Meson SoCs. The code is based on the public S805 (Meson8b) and S905 (GXBB) datasheets (see [0] and [1]), as well as by reading (various versions of) the vendor driver and by inspecting the registers on the vendor kernels of my testing-hardware. Currently the GXBB, GXL and GXM SoCs are supported. GXBB hardware has 10-bit ADC resolution, while GXL and GXM have 12-bit ADC resolution. The code was written to support older SoCs (Meson8 and Meson8b) as well, but due to lack of actual testing-hardware no of_device_id was added for these. Two "features" from the vendor driver are currently missing: - the vendor driver uses channel #7 for calibration (this improves the accuracy of the results - in my tests the results were less than 3% off without calibration compared to the vendor driver). Adding support for this should be easy, but is not required for most applications. - channel #6 is connected to the SoCs internal temperature sensor. Adding support for this is probably not so easy since (based on the u-boot sources) most SoC versions are using different registers and algorithms for the conversion from "ADC value" to temperature. Supported by the hardware but currently not supported by the driver: - reading multiple channels at the same time (the hardware has a FIFO buffer which stores multiple results) - continuous sampling (this would require a way to enable this individually because otherwise the ADC would be drawing power constantly) - interrupt support (similar to the vendor driver this new driver is polling the results. It is unclear if the IRQ-mode is supported on older (Meson6 or Meson8) hardware as well or if there are any errata) [0] http://dn.odroid.com/S805/Datasheet/S805_Datasheet%20V0.8%2020150126.pdf [1] http://dn.odroid.com/S905/DataSheet/S905_Public_Datasheet_V1.1.4.pdf Signed-off-by: Martin Blumenstingl <martin.blumenstingl@googlemail.com> Tested-by: Neil Armstrong <narmstrong@baylibre.com> Signed-off-by: Jonathan Cameron <jic23@kernel.org>
2017-01-23 02:17:13 +08:00
/*
* make sure we start at CH7 input since the other muxes are only used
* for internal calibration.
*/
meson_sar_adc_set_chan7_mux(indio_dev, CHAN7_MUX_CH7_INPUT);
if (priv->param->has_bl30_integration) {
/*
* leave sampling delay and the input clocks as configured by
* BL30 to make sure BL30 gets the values it expects when
* reading the temperature sensor.
*/
regmap_read(priv->regmap, MESON_SAR_ADC_REG3, &regval);
if (regval & MESON_SAR_ADC_REG3_BL30_INITIALIZED)
return 0;
}
iio: adc: add a driver for the SAR ADC found in Amlogic Meson SoCs This adds support for the SAR (Successive Approximation Register) ADC on the Amlogic Meson SoCs. The code is based on the public S805 (Meson8b) and S905 (GXBB) datasheets (see [0] and [1]), as well as by reading (various versions of) the vendor driver and by inspecting the registers on the vendor kernels of my testing-hardware. Currently the GXBB, GXL and GXM SoCs are supported. GXBB hardware has 10-bit ADC resolution, while GXL and GXM have 12-bit ADC resolution. The code was written to support older SoCs (Meson8 and Meson8b) as well, but due to lack of actual testing-hardware no of_device_id was added for these. Two "features" from the vendor driver are currently missing: - the vendor driver uses channel #7 for calibration (this improves the accuracy of the results - in my tests the results were less than 3% off without calibration compared to the vendor driver). Adding support for this should be easy, but is not required for most applications. - channel #6 is connected to the SoCs internal temperature sensor. Adding support for this is probably not so easy since (based on the u-boot sources) most SoC versions are using different registers and algorithms for the conversion from "ADC value" to temperature. Supported by the hardware but currently not supported by the driver: - reading multiple channels at the same time (the hardware has a FIFO buffer which stores multiple results) - continuous sampling (this would require a way to enable this individually because otherwise the ADC would be drawing power constantly) - interrupt support (similar to the vendor driver this new driver is polling the results. It is unclear if the IRQ-mode is supported on older (Meson6 or Meson8) hardware as well or if there are any errata) [0] http://dn.odroid.com/S805/Datasheet/S805_Datasheet%20V0.8%2020150126.pdf [1] http://dn.odroid.com/S905/DataSheet/S905_Public_Datasheet_V1.1.4.pdf Signed-off-by: Martin Blumenstingl <martin.blumenstingl@googlemail.com> Tested-by: Neil Armstrong <narmstrong@baylibre.com> Signed-off-by: Jonathan Cameron <jic23@kernel.org>
2017-01-23 02:17:13 +08:00
meson_sar_adc_stop_sample_engine(indio_dev);
iio: adc: meson-saradc: add support for the chip's temperature sensor Channel 6 of the SAR ADC can be switched between two inputs: SAR_ADC_CH6 input (an actual pad on the SoC) and the signal from the temperature sensor inside the SoC. To get usable results from the temperature sensor we need to read the corresponding calibration data from the eFuse and pass it to the SAR ADC registers. If the temperature sensor is not calibrated (the eFuse data contains a bit for this) then the driver will only register the iio_chan_spec's for voltage measurements. This only enables the temperature sensor for the Meson8 SoC. Meson8b and Meson8m2 SoCs can be supported in the future as well but we first need a way to pass the fifth TSC (temperature sensor coefficient) bit to the HHI register area (apart from that the infrastructure as already implemented for Meson8 can be used). On the 64-bit SoCs (GXBB, GXL and GXM) the temperature sensor inside SAR ADC is firmware-controlled (by BL30, we can simply use the SCPI hwmon driver to get the chip temperature). To keep the devicetree interface backwards compatible we simply skip the temperature sensor initialization if no eFuse nvmem cell is passed via devicetree. The public documentation for the SAR ADC IP block does not explain how to use the registers to read the temperature. The logic from this patch is based on reading and understanding Amlogic's GPL kernel sources. Signed-off-by: Martin Blumenstingl <martin.blumenstingl@googlemail.com> Signed-off-by: Jonathan Cameron <Jonathan.Cameron@huawei.com>
2018-11-04 07:10:24 +08:00
/*
* disable this bit as seems to be only relevant for Meson6 (based
* on the vendor driver), which we don't support at the moment.
*/
iio: adc: add a driver for the SAR ADC found in Amlogic Meson SoCs This adds support for the SAR (Successive Approximation Register) ADC on the Amlogic Meson SoCs. The code is based on the public S805 (Meson8b) and S905 (GXBB) datasheets (see [0] and [1]), as well as by reading (various versions of) the vendor driver and by inspecting the registers on the vendor kernels of my testing-hardware. Currently the GXBB, GXL and GXM SoCs are supported. GXBB hardware has 10-bit ADC resolution, while GXL and GXM have 12-bit ADC resolution. The code was written to support older SoCs (Meson8 and Meson8b) as well, but due to lack of actual testing-hardware no of_device_id was added for these. Two "features" from the vendor driver are currently missing: - the vendor driver uses channel #7 for calibration (this improves the accuracy of the results - in my tests the results were less than 3% off without calibration compared to the vendor driver). Adding support for this should be easy, but is not required for most applications. - channel #6 is connected to the SoCs internal temperature sensor. Adding support for this is probably not so easy since (based on the u-boot sources) most SoC versions are using different registers and algorithms for the conversion from "ADC value" to temperature. Supported by the hardware but currently not supported by the driver: - reading multiple channels at the same time (the hardware has a FIFO buffer which stores multiple results) - continuous sampling (this would require a way to enable this individually because otherwise the ADC would be drawing power constantly) - interrupt support (similar to the vendor driver this new driver is polling the results. It is unclear if the IRQ-mode is supported on older (Meson6 or Meson8) hardware as well or if there are any errata) [0] http://dn.odroid.com/S805/Datasheet/S805_Datasheet%20V0.8%2020150126.pdf [1] http://dn.odroid.com/S905/DataSheet/S905_Public_Datasheet_V1.1.4.pdf Signed-off-by: Martin Blumenstingl <martin.blumenstingl@googlemail.com> Tested-by: Neil Armstrong <narmstrong@baylibre.com> Signed-off-by: Jonathan Cameron <jic23@kernel.org>
2017-01-23 02:17:13 +08:00
regmap_update_bits(priv->regmap, MESON_SAR_ADC_REG0,
MESON_SAR_ADC_REG0_ADC_TEMP_SEN_SEL, 0);
iio: adc: add a driver for the SAR ADC found in Amlogic Meson SoCs This adds support for the SAR (Successive Approximation Register) ADC on the Amlogic Meson SoCs. The code is based on the public S805 (Meson8b) and S905 (GXBB) datasheets (see [0] and [1]), as well as by reading (various versions of) the vendor driver and by inspecting the registers on the vendor kernels of my testing-hardware. Currently the GXBB, GXL and GXM SoCs are supported. GXBB hardware has 10-bit ADC resolution, while GXL and GXM have 12-bit ADC resolution. The code was written to support older SoCs (Meson8 and Meson8b) as well, but due to lack of actual testing-hardware no of_device_id was added for these. Two "features" from the vendor driver are currently missing: - the vendor driver uses channel #7 for calibration (this improves the accuracy of the results - in my tests the results were less than 3% off without calibration compared to the vendor driver). Adding support for this should be easy, but is not required for most applications. - channel #6 is connected to the SoCs internal temperature sensor. Adding support for this is probably not so easy since (based on the u-boot sources) most SoC versions are using different registers and algorithms for the conversion from "ADC value" to temperature. Supported by the hardware but currently not supported by the driver: - reading multiple channels at the same time (the hardware has a FIFO buffer which stores multiple results) - continuous sampling (this would require a way to enable this individually because otherwise the ADC would be drawing power constantly) - interrupt support (similar to the vendor driver this new driver is polling the results. It is unclear if the IRQ-mode is supported on older (Meson6 or Meson8) hardware as well or if there are any errata) [0] http://dn.odroid.com/S805/Datasheet/S805_Datasheet%20V0.8%2020150126.pdf [1] http://dn.odroid.com/S905/DataSheet/S905_Public_Datasheet_V1.1.4.pdf Signed-off-by: Martin Blumenstingl <martin.blumenstingl@googlemail.com> Tested-by: Neil Armstrong <narmstrong@baylibre.com> Signed-off-by: Jonathan Cameron <jic23@kernel.org>
2017-01-23 02:17:13 +08:00
/* disable all channels by default */
regmap_write(priv->regmap, MESON_SAR_ADC_CHAN_LIST, 0x0);
regmap_update_bits(priv->regmap, MESON_SAR_ADC_REG3,
MESON_SAR_ADC_REG3_CTRL_SAMPLING_CLOCK_PHASE, 0);
regmap_update_bits(priv->regmap, MESON_SAR_ADC_REG3,
MESON_SAR_ADC_REG3_CNTL_USE_SC_DLY,
MESON_SAR_ADC_REG3_CNTL_USE_SC_DLY);
/* delay between two samples = (10+1) * 1uS */
regmap_update_bits(priv->regmap, MESON_SAR_ADC_DELAY,
MESON_SAR_ADC_DELAY_INPUT_DLY_CNT_MASK,
FIELD_PREP(MESON_SAR_ADC_DELAY_SAMPLE_DLY_CNT_MASK,
10));
regmap_update_bits(priv->regmap, MESON_SAR_ADC_DELAY,
MESON_SAR_ADC_DELAY_SAMPLE_DLY_SEL_MASK,
FIELD_PREP(MESON_SAR_ADC_DELAY_SAMPLE_DLY_SEL_MASK,
0));
/* delay between two samples = (10+1) * 1uS */
regmap_update_bits(priv->regmap, MESON_SAR_ADC_DELAY,
MESON_SAR_ADC_DELAY_INPUT_DLY_CNT_MASK,
FIELD_PREP(MESON_SAR_ADC_DELAY_INPUT_DLY_CNT_MASK,
10));
regmap_update_bits(priv->regmap, MESON_SAR_ADC_DELAY,
MESON_SAR_ADC_DELAY_INPUT_DLY_SEL_MASK,
FIELD_PREP(MESON_SAR_ADC_DELAY_INPUT_DLY_SEL_MASK,
1));
/*
* set up the input channel muxes in MESON_SAR_ADC_CHAN_10_SW
* (0 = SAR_ADC_CH0, 1 = SAR_ADC_CH1)
*/
regval = FIELD_PREP(MESON_SAR_ADC_CHAN_10_SW_CHAN0_MUX_SEL_MASK, 0);
regmap_update_bits(priv->regmap, MESON_SAR_ADC_CHAN_10_SW,
MESON_SAR_ADC_CHAN_10_SW_CHAN0_MUX_SEL_MASK,
regval);
regval = FIELD_PREP(MESON_SAR_ADC_CHAN_10_SW_CHAN1_MUX_SEL_MASK, 1);
regmap_update_bits(priv->regmap, MESON_SAR_ADC_CHAN_10_SW,
MESON_SAR_ADC_CHAN_10_SW_CHAN1_MUX_SEL_MASK,
regval);
regmap_update_bits(priv->regmap, MESON_SAR_ADC_CHAN_10_SW,
MESON_SAR_ADC_CHAN_10_SW_CHAN0_XP_DRIVE_SW,
MESON_SAR_ADC_CHAN_10_SW_CHAN0_XP_DRIVE_SW);
regmap_update_bits(priv->regmap, MESON_SAR_ADC_CHAN_10_SW,
MESON_SAR_ADC_CHAN_10_SW_CHAN0_YP_DRIVE_SW,
MESON_SAR_ADC_CHAN_10_SW_CHAN0_YP_DRIVE_SW);
regmap_update_bits(priv->regmap, MESON_SAR_ADC_CHAN_10_SW,
MESON_SAR_ADC_CHAN_10_SW_CHAN1_XP_DRIVE_SW,
MESON_SAR_ADC_CHAN_10_SW_CHAN1_XP_DRIVE_SW);
regmap_update_bits(priv->regmap, MESON_SAR_ADC_CHAN_10_SW,
MESON_SAR_ADC_CHAN_10_SW_CHAN1_YP_DRIVE_SW,
MESON_SAR_ADC_CHAN_10_SW_CHAN1_YP_DRIVE_SW);
/*
* set up the input channel muxes in MESON_SAR_ADC_AUX_SW
* (2 = SAR_ADC_CH2, 3 = SAR_ADC_CH3, ...) and enable
* MESON_SAR_ADC_AUX_SW_YP_DRIVE_SW and
* MESON_SAR_ADC_AUX_SW_XP_DRIVE_SW like the vendor driver.
*/
regval = 0;
for (i = 2; i <= 7; i++)
regval |= i << MESON_SAR_ADC_AUX_SW_MUX_SEL_CHAN_SHIFT(i);
regval |= MESON_SAR_ADC_AUX_SW_YP_DRIVE_SW;
regval |= MESON_SAR_ADC_AUX_SW_XP_DRIVE_SW;
regmap_write(priv->regmap, MESON_SAR_ADC_AUX_SW, regval);
iio: adc: meson-saradc: add support for the chip's temperature sensor Channel 6 of the SAR ADC can be switched between two inputs: SAR_ADC_CH6 input (an actual pad on the SoC) and the signal from the temperature sensor inside the SoC. To get usable results from the temperature sensor we need to read the corresponding calibration data from the eFuse and pass it to the SAR ADC registers. If the temperature sensor is not calibrated (the eFuse data contains a bit for this) then the driver will only register the iio_chan_spec's for voltage measurements. This only enables the temperature sensor for the Meson8 SoC. Meson8b and Meson8m2 SoCs can be supported in the future as well but we first need a way to pass the fifth TSC (temperature sensor coefficient) bit to the HHI register area (apart from that the infrastructure as already implemented for Meson8 can be used). On the 64-bit SoCs (GXBB, GXL and GXM) the temperature sensor inside SAR ADC is firmware-controlled (by BL30, we can simply use the SCPI hwmon driver to get the chip temperature). To keep the devicetree interface backwards compatible we simply skip the temperature sensor initialization if no eFuse nvmem cell is passed via devicetree. The public documentation for the SAR ADC IP block does not explain how to use the registers to read the temperature. The logic from this patch is based on reading and understanding Amlogic's GPL kernel sources. Signed-off-by: Martin Blumenstingl <martin.blumenstingl@googlemail.com> Signed-off-by: Jonathan Cameron <Jonathan.Cameron@huawei.com>
2018-11-04 07:10:24 +08:00
if (priv->temperature_sensor_calibrated) {
regmap_update_bits(priv->regmap, MESON_SAR_ADC_DELTA_10,
MESON_SAR_ADC_DELTA_10_TS_REVE1,
MESON_SAR_ADC_DELTA_10_TS_REVE1);
regmap_update_bits(priv->regmap, MESON_SAR_ADC_DELTA_10,
MESON_SAR_ADC_DELTA_10_TS_REVE0,
MESON_SAR_ADC_DELTA_10_TS_REVE0);
/*
* set bits [3:0] of the TSC (temperature sensor coefficient)
* to get the correct values when reading the temperature.
*/
regval = FIELD_PREP(MESON_SAR_ADC_DELTA_10_TS_C_MASK,
priv->temperature_sensor_coefficient);
regmap_update_bits(priv->regmap, MESON_SAR_ADC_DELTA_10,
MESON_SAR_ADC_DELTA_10_TS_C_MASK, regval);
if (priv->param->temperature_trimming_bits == 5) {
if (priv->temperature_sensor_coefficient & BIT(4))
regval = MESON_HHI_DPLL_TOP_0_TSC_BIT4;
else
regval = 0;
/*
* bit [4] (the 5th bit when starting to count at 1)
* of the TSC is located in the HHI register area.
*/
regmap_update_bits(priv->tsc_regmap,
MESON_HHI_DPLL_TOP_0,
MESON_HHI_DPLL_TOP_0_TSC_BIT4,
regval);
}
iio: adc: meson-saradc: add support for the chip's temperature sensor Channel 6 of the SAR ADC can be switched between two inputs: SAR_ADC_CH6 input (an actual pad on the SoC) and the signal from the temperature sensor inside the SoC. To get usable results from the temperature sensor we need to read the corresponding calibration data from the eFuse and pass it to the SAR ADC registers. If the temperature sensor is not calibrated (the eFuse data contains a bit for this) then the driver will only register the iio_chan_spec's for voltage measurements. This only enables the temperature sensor for the Meson8 SoC. Meson8b and Meson8m2 SoCs can be supported in the future as well but we first need a way to pass the fifth TSC (temperature sensor coefficient) bit to the HHI register area (apart from that the infrastructure as already implemented for Meson8 can be used). On the 64-bit SoCs (GXBB, GXL and GXM) the temperature sensor inside SAR ADC is firmware-controlled (by BL30, we can simply use the SCPI hwmon driver to get the chip temperature). To keep the devicetree interface backwards compatible we simply skip the temperature sensor initialization if no eFuse nvmem cell is passed via devicetree. The public documentation for the SAR ADC IP block does not explain how to use the registers to read the temperature. The logic from this patch is based on reading and understanding Amlogic's GPL kernel sources. Signed-off-by: Martin Blumenstingl <martin.blumenstingl@googlemail.com> Signed-off-by: Jonathan Cameron <Jonathan.Cameron@huawei.com>
2018-11-04 07:10:24 +08:00
} else {
regmap_update_bits(priv->regmap, MESON_SAR_ADC_DELTA_10,
MESON_SAR_ADC_DELTA_10_TS_REVE1, 0);
regmap_update_bits(priv->regmap, MESON_SAR_ADC_DELTA_10,
MESON_SAR_ADC_DELTA_10_TS_REVE0, 0);
}
regval = FIELD_PREP(MESON_SAR_ADC_REG3_CTRL_CONT_RING_COUNTER_EN,
priv->param->disable_ring_counter);
regmap_update_bits(priv->regmap, MESON_SAR_ADC_REG3,
MESON_SAR_ADC_REG3_CTRL_CONT_RING_COUNTER_EN,
regval);
if (priv->param->has_reg11) {
regval = FIELD_PREP(MESON_SAR_ADC_REG11_EOC, priv->param->adc_eoc);
regmap_update_bits(priv->regmap, MESON_SAR_ADC_REG11,
MESON_SAR_ADC_REG11_EOC, regval);
if (priv->param->has_vref_select) {
regval = FIELD_PREP(MESON_SAR_ADC_REG11_VREF_SEL,
priv->param->vref_select);
regmap_update_bits(priv->regmap, MESON_SAR_ADC_REG11,
MESON_SAR_ADC_REG11_VREF_SEL, regval);
}
regval = FIELD_PREP(MESON_SAR_ADC_REG11_VREF_VOLTAGE,
priv->param->vref_volatge);
regmap_update_bits(priv->regmap, MESON_SAR_ADC_REG11,
MESON_SAR_ADC_REG11_VREF_VOLTAGE, regval);
regval = FIELD_PREP(MESON_SAR_ADC_REG11_CMV_SEL,
priv->param->cmv_select);
regmap_update_bits(priv->regmap, MESON_SAR_ADC_REG11,
MESON_SAR_ADC_REG11_CMV_SEL, regval);
}
iio: adc: add a driver for the SAR ADC found in Amlogic Meson SoCs This adds support for the SAR (Successive Approximation Register) ADC on the Amlogic Meson SoCs. The code is based on the public S805 (Meson8b) and S905 (GXBB) datasheets (see [0] and [1]), as well as by reading (various versions of) the vendor driver and by inspecting the registers on the vendor kernels of my testing-hardware. Currently the GXBB, GXL and GXM SoCs are supported. GXBB hardware has 10-bit ADC resolution, while GXL and GXM have 12-bit ADC resolution. The code was written to support older SoCs (Meson8 and Meson8b) as well, but due to lack of actual testing-hardware no of_device_id was added for these. Two "features" from the vendor driver are currently missing: - the vendor driver uses channel #7 for calibration (this improves the accuracy of the results - in my tests the results were less than 3% off without calibration compared to the vendor driver). Adding support for this should be easy, but is not required for most applications. - channel #6 is connected to the SoCs internal temperature sensor. Adding support for this is probably not so easy since (based on the u-boot sources) most SoC versions are using different registers and algorithms for the conversion from "ADC value" to temperature. Supported by the hardware but currently not supported by the driver: - reading multiple channels at the same time (the hardware has a FIFO buffer which stores multiple results) - continuous sampling (this would require a way to enable this individually because otherwise the ADC would be drawing power constantly) - interrupt support (similar to the vendor driver this new driver is polling the results. It is unclear if the IRQ-mode is supported on older (Meson6 or Meson8) hardware as well or if there are any errata) [0] http://dn.odroid.com/S805/Datasheet/S805_Datasheet%20V0.8%2020150126.pdf [1] http://dn.odroid.com/S905/DataSheet/S905_Public_Datasheet_V1.1.4.pdf Signed-off-by: Martin Blumenstingl <martin.blumenstingl@googlemail.com> Tested-by: Neil Armstrong <narmstrong@baylibre.com> Signed-off-by: Jonathan Cameron <jic23@kernel.org>
2017-01-23 02:17:13 +08:00
ret = clk_set_parent(priv->adc_sel_clk, priv->clkin);
if (ret)
return dev_err_probe(dev, ret, "failed to set adc parent to clkin\n");
iio: adc: add a driver for the SAR ADC found in Amlogic Meson SoCs This adds support for the SAR (Successive Approximation Register) ADC on the Amlogic Meson SoCs. The code is based on the public S805 (Meson8b) and S905 (GXBB) datasheets (see [0] and [1]), as well as by reading (various versions of) the vendor driver and by inspecting the registers on the vendor kernels of my testing-hardware. Currently the GXBB, GXL and GXM SoCs are supported. GXBB hardware has 10-bit ADC resolution, while GXL and GXM have 12-bit ADC resolution. The code was written to support older SoCs (Meson8 and Meson8b) as well, but due to lack of actual testing-hardware no of_device_id was added for these. Two "features" from the vendor driver are currently missing: - the vendor driver uses channel #7 for calibration (this improves the accuracy of the results - in my tests the results were less than 3% off without calibration compared to the vendor driver). Adding support for this should be easy, but is not required for most applications. - channel #6 is connected to the SoCs internal temperature sensor. Adding support for this is probably not so easy since (based on the u-boot sources) most SoC versions are using different registers and algorithms for the conversion from "ADC value" to temperature. Supported by the hardware but currently not supported by the driver: - reading multiple channels at the same time (the hardware has a FIFO buffer which stores multiple results) - continuous sampling (this would require a way to enable this individually because otherwise the ADC would be drawing power constantly) - interrupt support (similar to the vendor driver this new driver is polling the results. It is unclear if the IRQ-mode is supported on older (Meson6 or Meson8) hardware as well or if there are any errata) [0] http://dn.odroid.com/S805/Datasheet/S805_Datasheet%20V0.8%2020150126.pdf [1] http://dn.odroid.com/S905/DataSheet/S905_Public_Datasheet_V1.1.4.pdf Signed-off-by: Martin Blumenstingl <martin.blumenstingl@googlemail.com> Tested-by: Neil Armstrong <narmstrong@baylibre.com> Signed-off-by: Jonathan Cameron <jic23@kernel.org>
2017-01-23 02:17:13 +08:00
ret = clk_set_rate(priv->adc_clk, priv->param->clock_rate);
if (ret)
return dev_err_probe(dev, ret, "failed to set adc clock rate\n");
iio: adc: add a driver for the SAR ADC found in Amlogic Meson SoCs This adds support for the SAR (Successive Approximation Register) ADC on the Amlogic Meson SoCs. The code is based on the public S805 (Meson8b) and S905 (GXBB) datasheets (see [0] and [1]), as well as by reading (various versions of) the vendor driver and by inspecting the registers on the vendor kernels of my testing-hardware. Currently the GXBB, GXL and GXM SoCs are supported. GXBB hardware has 10-bit ADC resolution, while GXL and GXM have 12-bit ADC resolution. The code was written to support older SoCs (Meson8 and Meson8b) as well, but due to lack of actual testing-hardware no of_device_id was added for these. Two "features" from the vendor driver are currently missing: - the vendor driver uses channel #7 for calibration (this improves the accuracy of the results - in my tests the results were less than 3% off without calibration compared to the vendor driver). Adding support for this should be easy, but is not required for most applications. - channel #6 is connected to the SoCs internal temperature sensor. Adding support for this is probably not so easy since (based on the u-boot sources) most SoC versions are using different registers and algorithms for the conversion from "ADC value" to temperature. Supported by the hardware but currently not supported by the driver: - reading multiple channels at the same time (the hardware has a FIFO buffer which stores multiple results) - continuous sampling (this would require a way to enable this individually because otherwise the ADC would be drawing power constantly) - interrupt support (similar to the vendor driver this new driver is polling the results. It is unclear if the IRQ-mode is supported on older (Meson6 or Meson8) hardware as well or if there are any errata) [0] http://dn.odroid.com/S805/Datasheet/S805_Datasheet%20V0.8%2020150126.pdf [1] http://dn.odroid.com/S905/DataSheet/S905_Public_Datasheet_V1.1.4.pdf Signed-off-by: Martin Blumenstingl <martin.blumenstingl@googlemail.com> Tested-by: Neil Armstrong <narmstrong@baylibre.com> Signed-off-by: Jonathan Cameron <jic23@kernel.org>
2017-01-23 02:17:13 +08:00
return 0;
}
static void meson_sar_adc_set_bandgap(struct iio_dev *indio_dev, bool on_off)
{
struct meson_sar_adc_priv *priv = iio_priv(indio_dev);
const struct meson_sar_adc_param *param = priv->param;
u32 enable_mask;
if (param->bandgap_reg == MESON_SAR_ADC_REG11)
enable_mask = MESON_SAR_ADC_REG11_BANDGAP_EN;
else
enable_mask = MESON_SAR_ADC_DELTA_10_TS_VBG_EN;
regmap_update_bits(priv->regmap, param->bandgap_reg, enable_mask,
on_off ? enable_mask : 0);
}
iio: adc: add a driver for the SAR ADC found in Amlogic Meson SoCs This adds support for the SAR (Successive Approximation Register) ADC on the Amlogic Meson SoCs. The code is based on the public S805 (Meson8b) and S905 (GXBB) datasheets (see [0] and [1]), as well as by reading (various versions of) the vendor driver and by inspecting the registers on the vendor kernels of my testing-hardware. Currently the GXBB, GXL and GXM SoCs are supported. GXBB hardware has 10-bit ADC resolution, while GXL and GXM have 12-bit ADC resolution. The code was written to support older SoCs (Meson8 and Meson8b) as well, but due to lack of actual testing-hardware no of_device_id was added for these. Two "features" from the vendor driver are currently missing: - the vendor driver uses channel #7 for calibration (this improves the accuracy of the results - in my tests the results were less than 3% off without calibration compared to the vendor driver). Adding support for this should be easy, but is not required for most applications. - channel #6 is connected to the SoCs internal temperature sensor. Adding support for this is probably not so easy since (based on the u-boot sources) most SoC versions are using different registers and algorithms for the conversion from "ADC value" to temperature. Supported by the hardware but currently not supported by the driver: - reading multiple channels at the same time (the hardware has a FIFO buffer which stores multiple results) - continuous sampling (this would require a way to enable this individually because otherwise the ADC would be drawing power constantly) - interrupt support (similar to the vendor driver this new driver is polling the results. It is unclear if the IRQ-mode is supported on older (Meson6 or Meson8) hardware as well or if there are any errata) [0] http://dn.odroid.com/S805/Datasheet/S805_Datasheet%20V0.8%2020150126.pdf [1] http://dn.odroid.com/S905/DataSheet/S905_Public_Datasheet_V1.1.4.pdf Signed-off-by: Martin Blumenstingl <martin.blumenstingl@googlemail.com> Tested-by: Neil Armstrong <narmstrong@baylibre.com> Signed-off-by: Jonathan Cameron <jic23@kernel.org>
2017-01-23 02:17:13 +08:00
static int meson_sar_adc_hw_enable(struct iio_dev *indio_dev)
{
struct meson_sar_adc_priv *priv = iio_priv(indio_dev);
struct device *dev = indio_dev->dev.parent;
iio: adc: add a driver for the SAR ADC found in Amlogic Meson SoCs This adds support for the SAR (Successive Approximation Register) ADC on the Amlogic Meson SoCs. The code is based on the public S805 (Meson8b) and S905 (GXBB) datasheets (see [0] and [1]), as well as by reading (various versions of) the vendor driver and by inspecting the registers on the vendor kernels of my testing-hardware. Currently the GXBB, GXL and GXM SoCs are supported. GXBB hardware has 10-bit ADC resolution, while GXL and GXM have 12-bit ADC resolution. The code was written to support older SoCs (Meson8 and Meson8b) as well, but due to lack of actual testing-hardware no of_device_id was added for these. Two "features" from the vendor driver are currently missing: - the vendor driver uses channel #7 for calibration (this improves the accuracy of the results - in my tests the results were less than 3% off without calibration compared to the vendor driver). Adding support for this should be easy, but is not required for most applications. - channel #6 is connected to the SoCs internal temperature sensor. Adding support for this is probably not so easy since (based on the u-boot sources) most SoC versions are using different registers and algorithms for the conversion from "ADC value" to temperature. Supported by the hardware but currently not supported by the driver: - reading multiple channels at the same time (the hardware has a FIFO buffer which stores multiple results) - continuous sampling (this would require a way to enable this individually because otherwise the ADC would be drawing power constantly) - interrupt support (similar to the vendor driver this new driver is polling the results. It is unclear if the IRQ-mode is supported on older (Meson6 or Meson8) hardware as well or if there are any errata) [0] http://dn.odroid.com/S805/Datasheet/S805_Datasheet%20V0.8%2020150126.pdf [1] http://dn.odroid.com/S905/DataSheet/S905_Public_Datasheet_V1.1.4.pdf Signed-off-by: Martin Blumenstingl <martin.blumenstingl@googlemail.com> Tested-by: Neil Armstrong <narmstrong@baylibre.com> Signed-off-by: Jonathan Cameron <jic23@kernel.org>
2017-01-23 02:17:13 +08:00
int ret;
u32 regval;
iio: adc: add a driver for the SAR ADC found in Amlogic Meson SoCs This adds support for the SAR (Successive Approximation Register) ADC on the Amlogic Meson SoCs. The code is based on the public S805 (Meson8b) and S905 (GXBB) datasheets (see [0] and [1]), as well as by reading (various versions of) the vendor driver and by inspecting the registers on the vendor kernels of my testing-hardware. Currently the GXBB, GXL and GXM SoCs are supported. GXBB hardware has 10-bit ADC resolution, while GXL and GXM have 12-bit ADC resolution. The code was written to support older SoCs (Meson8 and Meson8b) as well, but due to lack of actual testing-hardware no of_device_id was added for these. Two "features" from the vendor driver are currently missing: - the vendor driver uses channel #7 for calibration (this improves the accuracy of the results - in my tests the results were less than 3% off without calibration compared to the vendor driver). Adding support for this should be easy, but is not required for most applications. - channel #6 is connected to the SoCs internal temperature sensor. Adding support for this is probably not so easy since (based on the u-boot sources) most SoC versions are using different registers and algorithms for the conversion from "ADC value" to temperature. Supported by the hardware but currently not supported by the driver: - reading multiple channels at the same time (the hardware has a FIFO buffer which stores multiple results) - continuous sampling (this would require a way to enable this individually because otherwise the ADC would be drawing power constantly) - interrupt support (similar to the vendor driver this new driver is polling the results. It is unclear if the IRQ-mode is supported on older (Meson6 or Meson8) hardware as well or if there are any errata) [0] http://dn.odroid.com/S805/Datasheet/S805_Datasheet%20V0.8%2020150126.pdf [1] http://dn.odroid.com/S905/DataSheet/S905_Public_Datasheet_V1.1.4.pdf Signed-off-by: Martin Blumenstingl <martin.blumenstingl@googlemail.com> Tested-by: Neil Armstrong <narmstrong@baylibre.com> Signed-off-by: Jonathan Cameron <jic23@kernel.org>
2017-01-23 02:17:13 +08:00
ret = meson_sar_adc_lock(indio_dev);
if (ret)
goto err_lock;
ret = regulator_enable(priv->vref);
if (ret < 0) {
dev_err(dev, "failed to enable vref regulator\n");
iio: adc: add a driver for the SAR ADC found in Amlogic Meson SoCs This adds support for the SAR (Successive Approximation Register) ADC on the Amlogic Meson SoCs. The code is based on the public S805 (Meson8b) and S905 (GXBB) datasheets (see [0] and [1]), as well as by reading (various versions of) the vendor driver and by inspecting the registers on the vendor kernels of my testing-hardware. Currently the GXBB, GXL and GXM SoCs are supported. GXBB hardware has 10-bit ADC resolution, while GXL and GXM have 12-bit ADC resolution. The code was written to support older SoCs (Meson8 and Meson8b) as well, but due to lack of actual testing-hardware no of_device_id was added for these. Two "features" from the vendor driver are currently missing: - the vendor driver uses channel #7 for calibration (this improves the accuracy of the results - in my tests the results were less than 3% off without calibration compared to the vendor driver). Adding support for this should be easy, but is not required for most applications. - channel #6 is connected to the SoCs internal temperature sensor. Adding support for this is probably not so easy since (based on the u-boot sources) most SoC versions are using different registers and algorithms for the conversion from "ADC value" to temperature. Supported by the hardware but currently not supported by the driver: - reading multiple channels at the same time (the hardware has a FIFO buffer which stores multiple results) - continuous sampling (this would require a way to enable this individually because otherwise the ADC would be drawing power constantly) - interrupt support (similar to the vendor driver this new driver is polling the results. It is unclear if the IRQ-mode is supported on older (Meson6 or Meson8) hardware as well or if there are any errata) [0] http://dn.odroid.com/S805/Datasheet/S805_Datasheet%20V0.8%2020150126.pdf [1] http://dn.odroid.com/S905/DataSheet/S905_Public_Datasheet_V1.1.4.pdf Signed-off-by: Martin Blumenstingl <martin.blumenstingl@googlemail.com> Tested-by: Neil Armstrong <narmstrong@baylibre.com> Signed-off-by: Jonathan Cameron <jic23@kernel.org>
2017-01-23 02:17:13 +08:00
goto err_vref;
}
regval = FIELD_PREP(MESON_SAR_ADC_REG0_FIFO_CNT_IRQ_MASK, 1);
regmap_update_bits(priv->regmap, MESON_SAR_ADC_REG0,
MESON_SAR_ADC_REG0_FIFO_CNT_IRQ_MASK, regval);
meson_sar_adc_set_bandgap(indio_dev, true);
iio: adc: add a driver for the SAR ADC found in Amlogic Meson SoCs This adds support for the SAR (Successive Approximation Register) ADC on the Amlogic Meson SoCs. The code is based on the public S805 (Meson8b) and S905 (GXBB) datasheets (see [0] and [1]), as well as by reading (various versions of) the vendor driver and by inspecting the registers on the vendor kernels of my testing-hardware. Currently the GXBB, GXL and GXM SoCs are supported. GXBB hardware has 10-bit ADC resolution, while GXL and GXM have 12-bit ADC resolution. The code was written to support older SoCs (Meson8 and Meson8b) as well, but due to lack of actual testing-hardware no of_device_id was added for these. Two "features" from the vendor driver are currently missing: - the vendor driver uses channel #7 for calibration (this improves the accuracy of the results - in my tests the results were less than 3% off without calibration compared to the vendor driver). Adding support for this should be easy, but is not required for most applications. - channel #6 is connected to the SoCs internal temperature sensor. Adding support for this is probably not so easy since (based on the u-boot sources) most SoC versions are using different registers and algorithms for the conversion from "ADC value" to temperature. Supported by the hardware but currently not supported by the driver: - reading multiple channels at the same time (the hardware has a FIFO buffer which stores multiple results) - continuous sampling (this would require a way to enable this individually because otherwise the ADC would be drawing power constantly) - interrupt support (similar to the vendor driver this new driver is polling the results. It is unclear if the IRQ-mode is supported on older (Meson6 or Meson8) hardware as well or if there are any errata) [0] http://dn.odroid.com/S805/Datasheet/S805_Datasheet%20V0.8%2020150126.pdf [1] http://dn.odroid.com/S905/DataSheet/S905_Public_Datasheet_V1.1.4.pdf Signed-off-by: Martin Blumenstingl <martin.blumenstingl@googlemail.com> Tested-by: Neil Armstrong <narmstrong@baylibre.com> Signed-off-by: Jonathan Cameron <jic23@kernel.org>
2017-01-23 02:17:13 +08:00
regmap_update_bits(priv->regmap, MESON_SAR_ADC_REG3,
MESON_SAR_ADC_REG3_ADC_EN,
MESON_SAR_ADC_REG3_ADC_EN);
udelay(5);
ret = clk_prepare_enable(priv->adc_clk);
if (ret) {
dev_err(dev, "failed to enable adc clk\n");
iio: adc: add a driver for the SAR ADC found in Amlogic Meson SoCs This adds support for the SAR (Successive Approximation Register) ADC on the Amlogic Meson SoCs. The code is based on the public S805 (Meson8b) and S905 (GXBB) datasheets (see [0] and [1]), as well as by reading (various versions of) the vendor driver and by inspecting the registers on the vendor kernels of my testing-hardware. Currently the GXBB, GXL and GXM SoCs are supported. GXBB hardware has 10-bit ADC resolution, while GXL and GXM have 12-bit ADC resolution. The code was written to support older SoCs (Meson8 and Meson8b) as well, but due to lack of actual testing-hardware no of_device_id was added for these. Two "features" from the vendor driver are currently missing: - the vendor driver uses channel #7 for calibration (this improves the accuracy of the results - in my tests the results were less than 3% off without calibration compared to the vendor driver). Adding support for this should be easy, but is not required for most applications. - channel #6 is connected to the SoCs internal temperature sensor. Adding support for this is probably not so easy since (based on the u-boot sources) most SoC versions are using different registers and algorithms for the conversion from "ADC value" to temperature. Supported by the hardware but currently not supported by the driver: - reading multiple channels at the same time (the hardware has a FIFO buffer which stores multiple results) - continuous sampling (this would require a way to enable this individually because otherwise the ADC would be drawing power constantly) - interrupt support (similar to the vendor driver this new driver is polling the results. It is unclear if the IRQ-mode is supported on older (Meson6 or Meson8) hardware as well or if there are any errata) [0] http://dn.odroid.com/S805/Datasheet/S805_Datasheet%20V0.8%2020150126.pdf [1] http://dn.odroid.com/S905/DataSheet/S905_Public_Datasheet_V1.1.4.pdf Signed-off-by: Martin Blumenstingl <martin.blumenstingl@googlemail.com> Tested-by: Neil Armstrong <narmstrong@baylibre.com> Signed-off-by: Jonathan Cameron <jic23@kernel.org>
2017-01-23 02:17:13 +08:00
goto err_adc_clk;
}
meson_sar_adc_unlock(indio_dev);
return 0;
err_adc_clk:
regmap_update_bits(priv->regmap, MESON_SAR_ADC_REG3,
MESON_SAR_ADC_REG3_ADC_EN, 0);
meson_sar_adc_set_bandgap(indio_dev, false);
iio: adc: add a driver for the SAR ADC found in Amlogic Meson SoCs This adds support for the SAR (Successive Approximation Register) ADC on the Amlogic Meson SoCs. The code is based on the public S805 (Meson8b) and S905 (GXBB) datasheets (see [0] and [1]), as well as by reading (various versions of) the vendor driver and by inspecting the registers on the vendor kernels of my testing-hardware. Currently the GXBB, GXL and GXM SoCs are supported. GXBB hardware has 10-bit ADC resolution, while GXL and GXM have 12-bit ADC resolution. The code was written to support older SoCs (Meson8 and Meson8b) as well, but due to lack of actual testing-hardware no of_device_id was added for these. Two "features" from the vendor driver are currently missing: - the vendor driver uses channel #7 for calibration (this improves the accuracy of the results - in my tests the results were less than 3% off without calibration compared to the vendor driver). Adding support for this should be easy, but is not required for most applications. - channel #6 is connected to the SoCs internal temperature sensor. Adding support for this is probably not so easy since (based on the u-boot sources) most SoC versions are using different registers and algorithms for the conversion from "ADC value" to temperature. Supported by the hardware but currently not supported by the driver: - reading multiple channels at the same time (the hardware has a FIFO buffer which stores multiple results) - continuous sampling (this would require a way to enable this individually because otherwise the ADC would be drawing power constantly) - interrupt support (similar to the vendor driver this new driver is polling the results. It is unclear if the IRQ-mode is supported on older (Meson6 or Meson8) hardware as well or if there are any errata) [0] http://dn.odroid.com/S805/Datasheet/S805_Datasheet%20V0.8%2020150126.pdf [1] http://dn.odroid.com/S905/DataSheet/S905_Public_Datasheet_V1.1.4.pdf Signed-off-by: Martin Blumenstingl <martin.blumenstingl@googlemail.com> Tested-by: Neil Armstrong <narmstrong@baylibre.com> Signed-off-by: Jonathan Cameron <jic23@kernel.org>
2017-01-23 02:17:13 +08:00
regulator_disable(priv->vref);
err_vref:
meson_sar_adc_unlock(indio_dev);
err_lock:
return ret;
}
static void meson_sar_adc_hw_disable(struct iio_dev *indio_dev)
iio: adc: add a driver for the SAR ADC found in Amlogic Meson SoCs This adds support for the SAR (Successive Approximation Register) ADC on the Amlogic Meson SoCs. The code is based on the public S805 (Meson8b) and S905 (GXBB) datasheets (see [0] and [1]), as well as by reading (various versions of) the vendor driver and by inspecting the registers on the vendor kernels of my testing-hardware. Currently the GXBB, GXL and GXM SoCs are supported. GXBB hardware has 10-bit ADC resolution, while GXL and GXM have 12-bit ADC resolution. The code was written to support older SoCs (Meson8 and Meson8b) as well, but due to lack of actual testing-hardware no of_device_id was added for these. Two "features" from the vendor driver are currently missing: - the vendor driver uses channel #7 for calibration (this improves the accuracy of the results - in my tests the results were less than 3% off without calibration compared to the vendor driver). Adding support for this should be easy, but is not required for most applications. - channel #6 is connected to the SoCs internal temperature sensor. Adding support for this is probably not so easy since (based on the u-boot sources) most SoC versions are using different registers and algorithms for the conversion from "ADC value" to temperature. Supported by the hardware but currently not supported by the driver: - reading multiple channels at the same time (the hardware has a FIFO buffer which stores multiple results) - continuous sampling (this would require a way to enable this individually because otherwise the ADC would be drawing power constantly) - interrupt support (similar to the vendor driver this new driver is polling the results. It is unclear if the IRQ-mode is supported on older (Meson6 or Meson8) hardware as well or if there are any errata) [0] http://dn.odroid.com/S805/Datasheet/S805_Datasheet%20V0.8%2020150126.pdf [1] http://dn.odroid.com/S905/DataSheet/S905_Public_Datasheet_V1.1.4.pdf Signed-off-by: Martin Blumenstingl <martin.blumenstingl@googlemail.com> Tested-by: Neil Armstrong <narmstrong@baylibre.com> Signed-off-by: Jonathan Cameron <jic23@kernel.org>
2017-01-23 02:17:13 +08:00
{
struct meson_sar_adc_priv *priv = iio_priv(indio_dev);
int ret;
/*
* If taking the lock fails we have to assume that BL30 is broken. The
* best we can do then is to release the resources anyhow.
*/
iio: adc: add a driver for the SAR ADC found in Amlogic Meson SoCs This adds support for the SAR (Successive Approximation Register) ADC on the Amlogic Meson SoCs. The code is based on the public S805 (Meson8b) and S905 (GXBB) datasheets (see [0] and [1]), as well as by reading (various versions of) the vendor driver and by inspecting the registers on the vendor kernels of my testing-hardware. Currently the GXBB, GXL and GXM SoCs are supported. GXBB hardware has 10-bit ADC resolution, while GXL and GXM have 12-bit ADC resolution. The code was written to support older SoCs (Meson8 and Meson8b) as well, but due to lack of actual testing-hardware no of_device_id was added for these. Two "features" from the vendor driver are currently missing: - the vendor driver uses channel #7 for calibration (this improves the accuracy of the results - in my tests the results were less than 3% off without calibration compared to the vendor driver). Adding support for this should be easy, but is not required for most applications. - channel #6 is connected to the SoCs internal temperature sensor. Adding support for this is probably not so easy since (based on the u-boot sources) most SoC versions are using different registers and algorithms for the conversion from "ADC value" to temperature. Supported by the hardware but currently not supported by the driver: - reading multiple channels at the same time (the hardware has a FIFO buffer which stores multiple results) - continuous sampling (this would require a way to enable this individually because otherwise the ADC would be drawing power constantly) - interrupt support (similar to the vendor driver this new driver is polling the results. It is unclear if the IRQ-mode is supported on older (Meson6 or Meson8) hardware as well or if there are any errata) [0] http://dn.odroid.com/S805/Datasheet/S805_Datasheet%20V0.8%2020150126.pdf [1] http://dn.odroid.com/S905/DataSheet/S905_Public_Datasheet_V1.1.4.pdf Signed-off-by: Martin Blumenstingl <martin.blumenstingl@googlemail.com> Tested-by: Neil Armstrong <narmstrong@baylibre.com> Signed-off-by: Jonathan Cameron <jic23@kernel.org>
2017-01-23 02:17:13 +08:00
ret = meson_sar_adc_lock(indio_dev);
if (ret)
dev_err(indio_dev->dev.parent, "Failed to lock ADC (%pE)\n", ERR_PTR(ret));
iio: adc: add a driver for the SAR ADC found in Amlogic Meson SoCs This adds support for the SAR (Successive Approximation Register) ADC on the Amlogic Meson SoCs. The code is based on the public S805 (Meson8b) and S905 (GXBB) datasheets (see [0] and [1]), as well as by reading (various versions of) the vendor driver and by inspecting the registers on the vendor kernels of my testing-hardware. Currently the GXBB, GXL and GXM SoCs are supported. GXBB hardware has 10-bit ADC resolution, while GXL and GXM have 12-bit ADC resolution. The code was written to support older SoCs (Meson8 and Meson8b) as well, but due to lack of actual testing-hardware no of_device_id was added for these. Two "features" from the vendor driver are currently missing: - the vendor driver uses channel #7 for calibration (this improves the accuracy of the results - in my tests the results were less than 3% off without calibration compared to the vendor driver). Adding support for this should be easy, but is not required for most applications. - channel #6 is connected to the SoCs internal temperature sensor. Adding support for this is probably not so easy since (based on the u-boot sources) most SoC versions are using different registers and algorithms for the conversion from "ADC value" to temperature. Supported by the hardware but currently not supported by the driver: - reading multiple channels at the same time (the hardware has a FIFO buffer which stores multiple results) - continuous sampling (this would require a way to enable this individually because otherwise the ADC would be drawing power constantly) - interrupt support (similar to the vendor driver this new driver is polling the results. It is unclear if the IRQ-mode is supported on older (Meson6 or Meson8) hardware as well or if there are any errata) [0] http://dn.odroid.com/S805/Datasheet/S805_Datasheet%20V0.8%2020150126.pdf [1] http://dn.odroid.com/S905/DataSheet/S905_Public_Datasheet_V1.1.4.pdf Signed-off-by: Martin Blumenstingl <martin.blumenstingl@googlemail.com> Tested-by: Neil Armstrong <narmstrong@baylibre.com> Signed-off-by: Jonathan Cameron <jic23@kernel.org>
2017-01-23 02:17:13 +08:00
clk_disable_unprepare(priv->adc_clk);
regmap_update_bits(priv->regmap, MESON_SAR_ADC_REG3,
MESON_SAR_ADC_REG3_ADC_EN, 0);
meson_sar_adc_set_bandgap(indio_dev, false);
iio: adc: add a driver for the SAR ADC found in Amlogic Meson SoCs This adds support for the SAR (Successive Approximation Register) ADC on the Amlogic Meson SoCs. The code is based on the public S805 (Meson8b) and S905 (GXBB) datasheets (see [0] and [1]), as well as by reading (various versions of) the vendor driver and by inspecting the registers on the vendor kernels of my testing-hardware. Currently the GXBB, GXL and GXM SoCs are supported. GXBB hardware has 10-bit ADC resolution, while GXL and GXM have 12-bit ADC resolution. The code was written to support older SoCs (Meson8 and Meson8b) as well, but due to lack of actual testing-hardware no of_device_id was added for these. Two "features" from the vendor driver are currently missing: - the vendor driver uses channel #7 for calibration (this improves the accuracy of the results - in my tests the results were less than 3% off without calibration compared to the vendor driver). Adding support for this should be easy, but is not required for most applications. - channel #6 is connected to the SoCs internal temperature sensor. Adding support for this is probably not so easy since (based on the u-boot sources) most SoC versions are using different registers and algorithms for the conversion from "ADC value" to temperature. Supported by the hardware but currently not supported by the driver: - reading multiple channels at the same time (the hardware has a FIFO buffer which stores multiple results) - continuous sampling (this would require a way to enable this individually because otherwise the ADC would be drawing power constantly) - interrupt support (similar to the vendor driver this new driver is polling the results. It is unclear if the IRQ-mode is supported on older (Meson6 or Meson8) hardware as well or if there are any errata) [0] http://dn.odroid.com/S805/Datasheet/S805_Datasheet%20V0.8%2020150126.pdf [1] http://dn.odroid.com/S905/DataSheet/S905_Public_Datasheet_V1.1.4.pdf Signed-off-by: Martin Blumenstingl <martin.blumenstingl@googlemail.com> Tested-by: Neil Armstrong <narmstrong@baylibre.com> Signed-off-by: Jonathan Cameron <jic23@kernel.org>
2017-01-23 02:17:13 +08:00
regulator_disable(priv->vref);
if (!ret)
meson_sar_adc_unlock(indio_dev);
iio: adc: add a driver for the SAR ADC found in Amlogic Meson SoCs This adds support for the SAR (Successive Approximation Register) ADC on the Amlogic Meson SoCs. The code is based on the public S805 (Meson8b) and S905 (GXBB) datasheets (see [0] and [1]), as well as by reading (various versions of) the vendor driver and by inspecting the registers on the vendor kernels of my testing-hardware. Currently the GXBB, GXL and GXM SoCs are supported. GXBB hardware has 10-bit ADC resolution, while GXL and GXM have 12-bit ADC resolution. The code was written to support older SoCs (Meson8 and Meson8b) as well, but due to lack of actual testing-hardware no of_device_id was added for these. Two "features" from the vendor driver are currently missing: - the vendor driver uses channel #7 for calibration (this improves the accuracy of the results - in my tests the results were less than 3% off without calibration compared to the vendor driver). Adding support for this should be easy, but is not required for most applications. - channel #6 is connected to the SoCs internal temperature sensor. Adding support for this is probably not so easy since (based on the u-boot sources) most SoC versions are using different registers and algorithms for the conversion from "ADC value" to temperature. Supported by the hardware but currently not supported by the driver: - reading multiple channels at the same time (the hardware has a FIFO buffer which stores multiple results) - continuous sampling (this would require a way to enable this individually because otherwise the ADC would be drawing power constantly) - interrupt support (similar to the vendor driver this new driver is polling the results. It is unclear if the IRQ-mode is supported on older (Meson6 or Meson8) hardware as well or if there are any errata) [0] http://dn.odroid.com/S805/Datasheet/S805_Datasheet%20V0.8%2020150126.pdf [1] http://dn.odroid.com/S905/DataSheet/S905_Public_Datasheet_V1.1.4.pdf Signed-off-by: Martin Blumenstingl <martin.blumenstingl@googlemail.com> Tested-by: Neil Armstrong <narmstrong@baylibre.com> Signed-off-by: Jonathan Cameron <jic23@kernel.org>
2017-01-23 02:17:13 +08:00
}
static irqreturn_t meson_sar_adc_irq(int irq, void *data)
{
struct iio_dev *indio_dev = data;
struct meson_sar_adc_priv *priv = iio_priv(indio_dev);
unsigned int cnt, threshold;
u32 regval;
regmap_read(priv->regmap, MESON_SAR_ADC_REG0, &regval);
cnt = FIELD_GET(MESON_SAR_ADC_REG0_FIFO_COUNT_MASK, regval);
threshold = FIELD_GET(MESON_SAR_ADC_REG0_FIFO_CNT_IRQ_MASK, regval);
if (cnt < threshold)
return IRQ_NONE;
complete(&priv->done);
return IRQ_HANDLED;
}
static int meson_sar_adc_calib(struct iio_dev *indio_dev)
{
struct meson_sar_adc_priv *priv = iio_priv(indio_dev);
int ret, nominal0, nominal1, value0, value1;
/* use points 25% and 75% for calibration */
nominal0 = (1 << priv->param->resolution) / 4;
nominal1 = (1 << priv->param->resolution) * 3 / 4;
meson_sar_adc_set_chan7_mux(indio_dev, CHAN7_MUX_VDD_DIV4);
usleep_range(10, 20);
ret = meson_sar_adc_get_sample(indio_dev,
find_channel_by_num(indio_dev,
NUM_MUX_1_VDD_DIV4),
MEAN_AVERAGING, EIGHT_SAMPLES, &value0);
if (ret < 0)
goto out;
meson_sar_adc_set_chan7_mux(indio_dev, CHAN7_MUX_VDD_MUL3_DIV4);
usleep_range(10, 20);
ret = meson_sar_adc_get_sample(indio_dev,
find_channel_by_num(indio_dev,
NUM_MUX_3_VDD_MUL3_DIV4),
MEAN_AVERAGING, EIGHT_SAMPLES, &value1);
if (ret < 0)
goto out;
if (value1 <= value0) {
ret = -EINVAL;
goto out;
}
priv->calibscale = div_s64((nominal1 - nominal0) * (s64)MILLION,
value1 - value0);
priv->calibbias = nominal0 - div_s64((s64)value0 * priv->calibscale,
MILLION);
ret = 0;
out:
meson_sar_adc_set_chan7_mux(indio_dev, CHAN7_MUX_CH7_INPUT);
return ret;
}
static int read_label(struct iio_dev *indio_dev,
struct iio_chan_spec const *chan,
char *label)
{
if (chan->type == IIO_TEMP)
return sprintf(label, "temp-sensor\n");
if (chan->type == IIO_VOLTAGE && chan->channel >= NUM_MUX_0_VSS)
return sprintf(label, "%s\n",
chan7_mux_names[chan->channel - NUM_MUX_0_VSS]);
if (chan->type == IIO_VOLTAGE)
return sprintf(label, "channel-%d\n", chan->channel);
return 0;
}
iio: adc: add a driver for the SAR ADC found in Amlogic Meson SoCs This adds support for the SAR (Successive Approximation Register) ADC on the Amlogic Meson SoCs. The code is based on the public S805 (Meson8b) and S905 (GXBB) datasheets (see [0] and [1]), as well as by reading (various versions of) the vendor driver and by inspecting the registers on the vendor kernels of my testing-hardware. Currently the GXBB, GXL and GXM SoCs are supported. GXBB hardware has 10-bit ADC resolution, while GXL and GXM have 12-bit ADC resolution. The code was written to support older SoCs (Meson8 and Meson8b) as well, but due to lack of actual testing-hardware no of_device_id was added for these. Two "features" from the vendor driver are currently missing: - the vendor driver uses channel #7 for calibration (this improves the accuracy of the results - in my tests the results were less than 3% off without calibration compared to the vendor driver). Adding support for this should be easy, but is not required for most applications. - channel #6 is connected to the SoCs internal temperature sensor. Adding support for this is probably not so easy since (based on the u-boot sources) most SoC versions are using different registers and algorithms for the conversion from "ADC value" to temperature. Supported by the hardware but currently not supported by the driver: - reading multiple channels at the same time (the hardware has a FIFO buffer which stores multiple results) - continuous sampling (this would require a way to enable this individually because otherwise the ADC would be drawing power constantly) - interrupt support (similar to the vendor driver this new driver is polling the results. It is unclear if the IRQ-mode is supported on older (Meson6 or Meson8) hardware as well or if there are any errata) [0] http://dn.odroid.com/S805/Datasheet/S805_Datasheet%20V0.8%2020150126.pdf [1] http://dn.odroid.com/S905/DataSheet/S905_Public_Datasheet_V1.1.4.pdf Signed-off-by: Martin Blumenstingl <martin.blumenstingl@googlemail.com> Tested-by: Neil Armstrong <narmstrong@baylibre.com> Signed-off-by: Jonathan Cameron <jic23@kernel.org>
2017-01-23 02:17:13 +08:00
static const struct iio_info meson_sar_adc_iio_info = {
.read_raw = meson_sar_adc_iio_info_read_raw,
.read_label = read_label,
iio: adc: add a driver for the SAR ADC found in Amlogic Meson SoCs This adds support for the SAR (Successive Approximation Register) ADC on the Amlogic Meson SoCs. The code is based on the public S805 (Meson8b) and S905 (GXBB) datasheets (see [0] and [1]), as well as by reading (various versions of) the vendor driver and by inspecting the registers on the vendor kernels of my testing-hardware. Currently the GXBB, GXL and GXM SoCs are supported. GXBB hardware has 10-bit ADC resolution, while GXL and GXM have 12-bit ADC resolution. The code was written to support older SoCs (Meson8 and Meson8b) as well, but due to lack of actual testing-hardware no of_device_id was added for these. Two "features" from the vendor driver are currently missing: - the vendor driver uses channel #7 for calibration (this improves the accuracy of the results - in my tests the results were less than 3% off without calibration compared to the vendor driver). Adding support for this should be easy, but is not required for most applications. - channel #6 is connected to the SoCs internal temperature sensor. Adding support for this is probably not so easy since (based on the u-boot sources) most SoC versions are using different registers and algorithms for the conversion from "ADC value" to temperature. Supported by the hardware but currently not supported by the driver: - reading multiple channels at the same time (the hardware has a FIFO buffer which stores multiple results) - continuous sampling (this would require a way to enable this individually because otherwise the ADC would be drawing power constantly) - interrupt support (similar to the vendor driver this new driver is polling the results. It is unclear if the IRQ-mode is supported on older (Meson6 or Meson8) hardware as well or if there are any errata) [0] http://dn.odroid.com/S805/Datasheet/S805_Datasheet%20V0.8%2020150126.pdf [1] http://dn.odroid.com/S905/DataSheet/S905_Public_Datasheet_V1.1.4.pdf Signed-off-by: Martin Blumenstingl <martin.blumenstingl@googlemail.com> Tested-by: Neil Armstrong <narmstrong@baylibre.com> Signed-off-by: Jonathan Cameron <jic23@kernel.org>
2017-01-23 02:17:13 +08:00
};
static const struct meson_sar_adc_param meson_sar_adc_meson8_param = {
.has_bl30_integration = false,
.clock_rate = 1150000,
.bandgap_reg = MESON_SAR_ADC_DELTA_10,
.regmap_config = &meson_sar_adc_regmap_config_meson8,
.resolution = 10,
iio: adc: meson-saradc: add support for the chip's temperature sensor Channel 6 of the SAR ADC can be switched between two inputs: SAR_ADC_CH6 input (an actual pad on the SoC) and the signal from the temperature sensor inside the SoC. To get usable results from the temperature sensor we need to read the corresponding calibration data from the eFuse and pass it to the SAR ADC registers. If the temperature sensor is not calibrated (the eFuse data contains a bit for this) then the driver will only register the iio_chan_spec's for voltage measurements. This only enables the temperature sensor for the Meson8 SoC. Meson8b and Meson8m2 SoCs can be supported in the future as well but we first need a way to pass the fifth TSC (temperature sensor coefficient) bit to the HHI register area (apart from that the infrastructure as already implemented for Meson8 can be used). On the 64-bit SoCs (GXBB, GXL and GXM) the temperature sensor inside SAR ADC is firmware-controlled (by BL30, we can simply use the SCPI hwmon driver to get the chip temperature). To keep the devicetree interface backwards compatible we simply skip the temperature sensor initialization if no eFuse nvmem cell is passed via devicetree. The public documentation for the SAR ADC IP block does not explain how to use the registers to read the temperature. The logic from this patch is based on reading and understanding Amlogic's GPL kernel sources. Signed-off-by: Martin Blumenstingl <martin.blumenstingl@googlemail.com> Signed-off-by: Jonathan Cameron <Jonathan.Cameron@huawei.com>
2018-11-04 07:10:24 +08:00
.temperature_trimming_bits = 4,
.temperature_multiplier = 18 * 10000,
.temperature_divider = 1024 * 10 * 85,
};
static const struct meson_sar_adc_param meson_sar_adc_meson8b_param = {
.has_bl30_integration = false,
.clock_rate = 1150000,
.bandgap_reg = MESON_SAR_ADC_DELTA_10,
.regmap_config = &meson_sar_adc_regmap_config_meson8,
.resolution = 10,
.temperature_trimming_bits = 5,
.temperature_multiplier = 10,
.temperature_divider = 32,
};
static const struct meson_sar_adc_param meson_sar_adc_gxbb_param = {
.has_bl30_integration = true,
.clock_rate = 1200000,
.bandgap_reg = MESON_SAR_ADC_REG11,
.regmap_config = &meson_sar_adc_regmap_config_gxbb,
iio: adc: add a driver for the SAR ADC found in Amlogic Meson SoCs This adds support for the SAR (Successive Approximation Register) ADC on the Amlogic Meson SoCs. The code is based on the public S805 (Meson8b) and S905 (GXBB) datasheets (see [0] and [1]), as well as by reading (various versions of) the vendor driver and by inspecting the registers on the vendor kernels of my testing-hardware. Currently the GXBB, GXL and GXM SoCs are supported. GXBB hardware has 10-bit ADC resolution, while GXL and GXM have 12-bit ADC resolution. The code was written to support older SoCs (Meson8 and Meson8b) as well, but due to lack of actual testing-hardware no of_device_id was added for these. Two "features" from the vendor driver are currently missing: - the vendor driver uses channel #7 for calibration (this improves the accuracy of the results - in my tests the results were less than 3% off without calibration compared to the vendor driver). Adding support for this should be easy, but is not required for most applications. - channel #6 is connected to the SoCs internal temperature sensor. Adding support for this is probably not so easy since (based on the u-boot sources) most SoC versions are using different registers and algorithms for the conversion from "ADC value" to temperature. Supported by the hardware but currently not supported by the driver: - reading multiple channels at the same time (the hardware has a FIFO buffer which stores multiple results) - continuous sampling (this would require a way to enable this individually because otherwise the ADC would be drawing power constantly) - interrupt support (similar to the vendor driver this new driver is polling the results. It is unclear if the IRQ-mode is supported on older (Meson6 or Meson8) hardware as well or if there are any errata) [0] http://dn.odroid.com/S805/Datasheet/S805_Datasheet%20V0.8%2020150126.pdf [1] http://dn.odroid.com/S905/DataSheet/S905_Public_Datasheet_V1.1.4.pdf Signed-off-by: Martin Blumenstingl <martin.blumenstingl@googlemail.com> Tested-by: Neil Armstrong <narmstrong@baylibre.com> Signed-off-by: Jonathan Cameron <jic23@kernel.org>
2017-01-23 02:17:13 +08:00
.resolution = 10,
.has_reg11 = true,
.vref_volatge = 1,
.cmv_select = 1,
iio: adc: add a driver for the SAR ADC found in Amlogic Meson SoCs This adds support for the SAR (Successive Approximation Register) ADC on the Amlogic Meson SoCs. The code is based on the public S805 (Meson8b) and S905 (GXBB) datasheets (see [0] and [1]), as well as by reading (various versions of) the vendor driver and by inspecting the registers on the vendor kernels of my testing-hardware. Currently the GXBB, GXL and GXM SoCs are supported. GXBB hardware has 10-bit ADC resolution, while GXL and GXM have 12-bit ADC resolution. The code was written to support older SoCs (Meson8 and Meson8b) as well, but due to lack of actual testing-hardware no of_device_id was added for these. Two "features" from the vendor driver are currently missing: - the vendor driver uses channel #7 for calibration (this improves the accuracy of the results - in my tests the results were less than 3% off without calibration compared to the vendor driver). Adding support for this should be easy, but is not required for most applications. - channel #6 is connected to the SoCs internal temperature sensor. Adding support for this is probably not so easy since (based on the u-boot sources) most SoC versions are using different registers and algorithms for the conversion from "ADC value" to temperature. Supported by the hardware but currently not supported by the driver: - reading multiple channels at the same time (the hardware has a FIFO buffer which stores multiple results) - continuous sampling (this would require a way to enable this individually because otherwise the ADC would be drawing power constantly) - interrupt support (similar to the vendor driver this new driver is polling the results. It is unclear if the IRQ-mode is supported on older (Meson6 or Meson8) hardware as well or if there are any errata) [0] http://dn.odroid.com/S805/Datasheet/S805_Datasheet%20V0.8%2020150126.pdf [1] http://dn.odroid.com/S905/DataSheet/S905_Public_Datasheet_V1.1.4.pdf Signed-off-by: Martin Blumenstingl <martin.blumenstingl@googlemail.com> Tested-by: Neil Armstrong <narmstrong@baylibre.com> Signed-off-by: Jonathan Cameron <jic23@kernel.org>
2017-01-23 02:17:13 +08:00
};
static const struct meson_sar_adc_param meson_sar_adc_gxl_param = {
.has_bl30_integration = true,
.clock_rate = 1200000,
.bandgap_reg = MESON_SAR_ADC_REG11,
.regmap_config = &meson_sar_adc_regmap_config_gxbb,
iio: adc: add a driver for the SAR ADC found in Amlogic Meson SoCs This adds support for the SAR (Successive Approximation Register) ADC on the Amlogic Meson SoCs. The code is based on the public S805 (Meson8b) and S905 (GXBB) datasheets (see [0] and [1]), as well as by reading (various versions of) the vendor driver and by inspecting the registers on the vendor kernels of my testing-hardware. Currently the GXBB, GXL and GXM SoCs are supported. GXBB hardware has 10-bit ADC resolution, while GXL and GXM have 12-bit ADC resolution. The code was written to support older SoCs (Meson8 and Meson8b) as well, but due to lack of actual testing-hardware no of_device_id was added for these. Two "features" from the vendor driver are currently missing: - the vendor driver uses channel #7 for calibration (this improves the accuracy of the results - in my tests the results were less than 3% off without calibration compared to the vendor driver). Adding support for this should be easy, but is not required for most applications. - channel #6 is connected to the SoCs internal temperature sensor. Adding support for this is probably not so easy since (based on the u-boot sources) most SoC versions are using different registers and algorithms for the conversion from "ADC value" to temperature. Supported by the hardware but currently not supported by the driver: - reading multiple channels at the same time (the hardware has a FIFO buffer which stores multiple results) - continuous sampling (this would require a way to enable this individually because otherwise the ADC would be drawing power constantly) - interrupt support (similar to the vendor driver this new driver is polling the results. It is unclear if the IRQ-mode is supported on older (Meson6 or Meson8) hardware as well or if there are any errata) [0] http://dn.odroid.com/S805/Datasheet/S805_Datasheet%20V0.8%2020150126.pdf [1] http://dn.odroid.com/S905/DataSheet/S905_Public_Datasheet_V1.1.4.pdf Signed-off-by: Martin Blumenstingl <martin.blumenstingl@googlemail.com> Tested-by: Neil Armstrong <narmstrong@baylibre.com> Signed-off-by: Jonathan Cameron <jic23@kernel.org>
2017-01-23 02:17:13 +08:00
.resolution = 12,
.disable_ring_counter = 1,
.has_reg11 = true,
.vref_volatge = 1,
.cmv_select = 1,
};
static const struct meson_sar_adc_param meson_sar_adc_g12a_param = {
.has_bl30_integration = false,
.clock_rate = 1200000,
.bandgap_reg = MESON_SAR_ADC_REG11,
.regmap_config = &meson_sar_adc_regmap_config_gxbb,
.resolution = 12,
.disable_ring_counter = 1,
.has_reg11 = true,
.adc_eoc = 1,
.has_vref_select = true,
.vref_select = VREF_VDDA,
};
static const struct meson_sar_adc_data meson_sar_adc_meson8_data = {
.param = &meson_sar_adc_meson8_param,
.name = "meson-meson8-saradc",
};
static const struct meson_sar_adc_data meson_sar_adc_meson8b_data = {
iio: adc: meson-saradc: add support for the chip's temperature sensor Channel 6 of the SAR ADC can be switched between two inputs: SAR_ADC_CH6 input (an actual pad on the SoC) and the signal from the temperature sensor inside the SoC. To get usable results from the temperature sensor we need to read the corresponding calibration data from the eFuse and pass it to the SAR ADC registers. If the temperature sensor is not calibrated (the eFuse data contains a bit for this) then the driver will only register the iio_chan_spec's for voltage measurements. This only enables the temperature sensor for the Meson8 SoC. Meson8b and Meson8m2 SoCs can be supported in the future as well but we first need a way to pass the fifth TSC (temperature sensor coefficient) bit to the HHI register area (apart from that the infrastructure as already implemented for Meson8 can be used). On the 64-bit SoCs (GXBB, GXL and GXM) the temperature sensor inside SAR ADC is firmware-controlled (by BL30, we can simply use the SCPI hwmon driver to get the chip temperature). To keep the devicetree interface backwards compatible we simply skip the temperature sensor initialization if no eFuse nvmem cell is passed via devicetree. The public documentation for the SAR ADC IP block does not explain how to use the registers to read the temperature. The logic from this patch is based on reading and understanding Amlogic's GPL kernel sources. Signed-off-by: Martin Blumenstingl <martin.blumenstingl@googlemail.com> Signed-off-by: Jonathan Cameron <Jonathan.Cameron@huawei.com>
2018-11-04 07:10:24 +08:00
.param = &meson_sar_adc_meson8b_param,
.name = "meson-meson8b-saradc",
};
static const struct meson_sar_adc_data meson_sar_adc_meson8m2_data = {
iio: adc: meson-saradc: add support for the chip's temperature sensor Channel 6 of the SAR ADC can be switched between two inputs: SAR_ADC_CH6 input (an actual pad on the SoC) and the signal from the temperature sensor inside the SoC. To get usable results from the temperature sensor we need to read the corresponding calibration data from the eFuse and pass it to the SAR ADC registers. If the temperature sensor is not calibrated (the eFuse data contains a bit for this) then the driver will only register the iio_chan_spec's for voltage measurements. This only enables the temperature sensor for the Meson8 SoC. Meson8b and Meson8m2 SoCs can be supported in the future as well but we first need a way to pass the fifth TSC (temperature sensor coefficient) bit to the HHI register area (apart from that the infrastructure as already implemented for Meson8 can be used). On the 64-bit SoCs (GXBB, GXL and GXM) the temperature sensor inside SAR ADC is firmware-controlled (by BL30, we can simply use the SCPI hwmon driver to get the chip temperature). To keep the devicetree interface backwards compatible we simply skip the temperature sensor initialization if no eFuse nvmem cell is passed via devicetree. The public documentation for the SAR ADC IP block does not explain how to use the registers to read the temperature. The logic from this patch is based on reading and understanding Amlogic's GPL kernel sources. Signed-off-by: Martin Blumenstingl <martin.blumenstingl@googlemail.com> Signed-off-by: Jonathan Cameron <Jonathan.Cameron@huawei.com>
2018-11-04 07:10:24 +08:00
.param = &meson_sar_adc_meson8b_param,
.name = "meson-meson8m2-saradc",
};
static const struct meson_sar_adc_data meson_sar_adc_gxbb_data = {
.param = &meson_sar_adc_gxbb_param,
.name = "meson-gxbb-saradc",
};
static const struct meson_sar_adc_data meson_sar_adc_gxl_data = {
.param = &meson_sar_adc_gxl_param,
iio: adc: add a driver for the SAR ADC found in Amlogic Meson SoCs This adds support for the SAR (Successive Approximation Register) ADC on the Amlogic Meson SoCs. The code is based on the public S805 (Meson8b) and S905 (GXBB) datasheets (see [0] and [1]), as well as by reading (various versions of) the vendor driver and by inspecting the registers on the vendor kernels of my testing-hardware. Currently the GXBB, GXL and GXM SoCs are supported. GXBB hardware has 10-bit ADC resolution, while GXL and GXM have 12-bit ADC resolution. The code was written to support older SoCs (Meson8 and Meson8b) as well, but due to lack of actual testing-hardware no of_device_id was added for these. Two "features" from the vendor driver are currently missing: - the vendor driver uses channel #7 for calibration (this improves the accuracy of the results - in my tests the results were less than 3% off without calibration compared to the vendor driver). Adding support for this should be easy, but is not required for most applications. - channel #6 is connected to the SoCs internal temperature sensor. Adding support for this is probably not so easy since (based on the u-boot sources) most SoC versions are using different registers and algorithms for the conversion from "ADC value" to temperature. Supported by the hardware but currently not supported by the driver: - reading multiple channels at the same time (the hardware has a FIFO buffer which stores multiple results) - continuous sampling (this would require a way to enable this individually because otherwise the ADC would be drawing power constantly) - interrupt support (similar to the vendor driver this new driver is polling the results. It is unclear if the IRQ-mode is supported on older (Meson6 or Meson8) hardware as well or if there are any errata) [0] http://dn.odroid.com/S805/Datasheet/S805_Datasheet%20V0.8%2020150126.pdf [1] http://dn.odroid.com/S905/DataSheet/S905_Public_Datasheet_V1.1.4.pdf Signed-off-by: Martin Blumenstingl <martin.blumenstingl@googlemail.com> Tested-by: Neil Armstrong <narmstrong@baylibre.com> Signed-off-by: Jonathan Cameron <jic23@kernel.org>
2017-01-23 02:17:13 +08:00
.name = "meson-gxl-saradc",
};
static const struct meson_sar_adc_data meson_sar_adc_gxm_data = {
.param = &meson_sar_adc_gxl_param,
iio: adc: add a driver for the SAR ADC found in Amlogic Meson SoCs This adds support for the SAR (Successive Approximation Register) ADC on the Amlogic Meson SoCs. The code is based on the public S805 (Meson8b) and S905 (GXBB) datasheets (see [0] and [1]), as well as by reading (various versions of) the vendor driver and by inspecting the registers on the vendor kernels of my testing-hardware. Currently the GXBB, GXL and GXM SoCs are supported. GXBB hardware has 10-bit ADC resolution, while GXL and GXM have 12-bit ADC resolution. The code was written to support older SoCs (Meson8 and Meson8b) as well, but due to lack of actual testing-hardware no of_device_id was added for these. Two "features" from the vendor driver are currently missing: - the vendor driver uses channel #7 for calibration (this improves the accuracy of the results - in my tests the results were less than 3% off without calibration compared to the vendor driver). Adding support for this should be easy, but is not required for most applications. - channel #6 is connected to the SoCs internal temperature sensor. Adding support for this is probably not so easy since (based on the u-boot sources) most SoC versions are using different registers and algorithms for the conversion from "ADC value" to temperature. Supported by the hardware but currently not supported by the driver: - reading multiple channels at the same time (the hardware has a FIFO buffer which stores multiple results) - continuous sampling (this would require a way to enable this individually because otherwise the ADC would be drawing power constantly) - interrupt support (similar to the vendor driver this new driver is polling the results. It is unclear if the IRQ-mode is supported on older (Meson6 or Meson8) hardware as well or if there are any errata) [0] http://dn.odroid.com/S805/Datasheet/S805_Datasheet%20V0.8%2020150126.pdf [1] http://dn.odroid.com/S905/DataSheet/S905_Public_Datasheet_V1.1.4.pdf Signed-off-by: Martin Blumenstingl <martin.blumenstingl@googlemail.com> Tested-by: Neil Armstrong <narmstrong@baylibre.com> Signed-off-by: Jonathan Cameron <jic23@kernel.org>
2017-01-23 02:17:13 +08:00
.name = "meson-gxm-saradc",
};
static const struct meson_sar_adc_data meson_sar_adc_axg_data = {
.param = &meson_sar_adc_gxl_param,
.name = "meson-axg-saradc",
};
static const struct meson_sar_adc_data meson_sar_adc_g12a_data = {
.param = &meson_sar_adc_g12a_param,
.name = "meson-g12a-saradc",
};
iio: adc: add a driver for the SAR ADC found in Amlogic Meson SoCs This adds support for the SAR (Successive Approximation Register) ADC on the Amlogic Meson SoCs. The code is based on the public S805 (Meson8b) and S905 (GXBB) datasheets (see [0] and [1]), as well as by reading (various versions of) the vendor driver and by inspecting the registers on the vendor kernels of my testing-hardware. Currently the GXBB, GXL and GXM SoCs are supported. GXBB hardware has 10-bit ADC resolution, while GXL and GXM have 12-bit ADC resolution. The code was written to support older SoCs (Meson8 and Meson8b) as well, but due to lack of actual testing-hardware no of_device_id was added for these. Two "features" from the vendor driver are currently missing: - the vendor driver uses channel #7 for calibration (this improves the accuracy of the results - in my tests the results were less than 3% off without calibration compared to the vendor driver). Adding support for this should be easy, but is not required for most applications. - channel #6 is connected to the SoCs internal temperature sensor. Adding support for this is probably not so easy since (based on the u-boot sources) most SoC versions are using different registers and algorithms for the conversion from "ADC value" to temperature. Supported by the hardware but currently not supported by the driver: - reading multiple channels at the same time (the hardware has a FIFO buffer which stores multiple results) - continuous sampling (this would require a way to enable this individually because otherwise the ADC would be drawing power constantly) - interrupt support (similar to the vendor driver this new driver is polling the results. It is unclear if the IRQ-mode is supported on older (Meson6 or Meson8) hardware as well or if there are any errata) [0] http://dn.odroid.com/S805/Datasheet/S805_Datasheet%20V0.8%2020150126.pdf [1] http://dn.odroid.com/S905/DataSheet/S905_Public_Datasheet_V1.1.4.pdf Signed-off-by: Martin Blumenstingl <martin.blumenstingl@googlemail.com> Tested-by: Neil Armstrong <narmstrong@baylibre.com> Signed-off-by: Jonathan Cameron <jic23@kernel.org>
2017-01-23 02:17:13 +08:00
static const struct of_device_id meson_sar_adc_of_match[] = {
{
.compatible = "amlogic,meson8-saradc",
.data = &meson_sar_adc_meson8_data,
}, {
.compatible = "amlogic,meson8b-saradc",
.data = &meson_sar_adc_meson8b_data,
}, {
.compatible = "amlogic,meson8m2-saradc",
.data = &meson_sar_adc_meson8m2_data,
}, {
iio: adc: add a driver for the SAR ADC found in Amlogic Meson SoCs This adds support for the SAR (Successive Approximation Register) ADC on the Amlogic Meson SoCs. The code is based on the public S805 (Meson8b) and S905 (GXBB) datasheets (see [0] and [1]), as well as by reading (various versions of) the vendor driver and by inspecting the registers on the vendor kernels of my testing-hardware. Currently the GXBB, GXL and GXM SoCs are supported. GXBB hardware has 10-bit ADC resolution, while GXL and GXM have 12-bit ADC resolution. The code was written to support older SoCs (Meson8 and Meson8b) as well, but due to lack of actual testing-hardware no of_device_id was added for these. Two "features" from the vendor driver are currently missing: - the vendor driver uses channel #7 for calibration (this improves the accuracy of the results - in my tests the results were less than 3% off without calibration compared to the vendor driver). Adding support for this should be easy, but is not required for most applications. - channel #6 is connected to the SoCs internal temperature sensor. Adding support for this is probably not so easy since (based on the u-boot sources) most SoC versions are using different registers and algorithms for the conversion from "ADC value" to temperature. Supported by the hardware but currently not supported by the driver: - reading multiple channels at the same time (the hardware has a FIFO buffer which stores multiple results) - continuous sampling (this would require a way to enable this individually because otherwise the ADC would be drawing power constantly) - interrupt support (similar to the vendor driver this new driver is polling the results. It is unclear if the IRQ-mode is supported on older (Meson6 or Meson8) hardware as well or if there are any errata) [0] http://dn.odroid.com/S805/Datasheet/S805_Datasheet%20V0.8%2020150126.pdf [1] http://dn.odroid.com/S905/DataSheet/S905_Public_Datasheet_V1.1.4.pdf Signed-off-by: Martin Blumenstingl <martin.blumenstingl@googlemail.com> Tested-by: Neil Armstrong <narmstrong@baylibre.com> Signed-off-by: Jonathan Cameron <jic23@kernel.org>
2017-01-23 02:17:13 +08:00
.compatible = "amlogic,meson-gxbb-saradc",
.data = &meson_sar_adc_gxbb_data,
}, {
.compatible = "amlogic,meson-gxl-saradc",
.data = &meson_sar_adc_gxl_data,
}, {
.compatible = "amlogic,meson-gxm-saradc",
.data = &meson_sar_adc_gxm_data,
}, {
.compatible = "amlogic,meson-axg-saradc",
.data = &meson_sar_adc_axg_data,
}, {
.compatible = "amlogic,meson-g12a-saradc",
.data = &meson_sar_adc_g12a_data,
iio: adc: add a driver for the SAR ADC found in Amlogic Meson SoCs This adds support for the SAR (Successive Approximation Register) ADC on the Amlogic Meson SoCs. The code is based on the public S805 (Meson8b) and S905 (GXBB) datasheets (see [0] and [1]), as well as by reading (various versions of) the vendor driver and by inspecting the registers on the vendor kernels of my testing-hardware. Currently the GXBB, GXL and GXM SoCs are supported. GXBB hardware has 10-bit ADC resolution, while GXL and GXM have 12-bit ADC resolution. The code was written to support older SoCs (Meson8 and Meson8b) as well, but due to lack of actual testing-hardware no of_device_id was added for these. Two "features" from the vendor driver are currently missing: - the vendor driver uses channel #7 for calibration (this improves the accuracy of the results - in my tests the results were less than 3% off without calibration compared to the vendor driver). Adding support for this should be easy, but is not required for most applications. - channel #6 is connected to the SoCs internal temperature sensor. Adding support for this is probably not so easy since (based on the u-boot sources) most SoC versions are using different registers and algorithms for the conversion from "ADC value" to temperature. Supported by the hardware but currently not supported by the driver: - reading multiple channels at the same time (the hardware has a FIFO buffer which stores multiple results) - continuous sampling (this would require a way to enable this individually because otherwise the ADC would be drawing power constantly) - interrupt support (similar to the vendor driver this new driver is polling the results. It is unclear if the IRQ-mode is supported on older (Meson6 or Meson8) hardware as well or if there are any errata) [0] http://dn.odroid.com/S805/Datasheet/S805_Datasheet%20V0.8%2020150126.pdf [1] http://dn.odroid.com/S905/DataSheet/S905_Public_Datasheet_V1.1.4.pdf Signed-off-by: Martin Blumenstingl <martin.blumenstingl@googlemail.com> Tested-by: Neil Armstrong <narmstrong@baylibre.com> Signed-off-by: Jonathan Cameron <jic23@kernel.org>
2017-01-23 02:17:13 +08:00
},
{ /* sentinel */ }
iio: adc: add a driver for the SAR ADC found in Amlogic Meson SoCs This adds support for the SAR (Successive Approximation Register) ADC on the Amlogic Meson SoCs. The code is based on the public S805 (Meson8b) and S905 (GXBB) datasheets (see [0] and [1]), as well as by reading (various versions of) the vendor driver and by inspecting the registers on the vendor kernels of my testing-hardware. Currently the GXBB, GXL and GXM SoCs are supported. GXBB hardware has 10-bit ADC resolution, while GXL and GXM have 12-bit ADC resolution. The code was written to support older SoCs (Meson8 and Meson8b) as well, but due to lack of actual testing-hardware no of_device_id was added for these. Two "features" from the vendor driver are currently missing: - the vendor driver uses channel #7 for calibration (this improves the accuracy of the results - in my tests the results were less than 3% off without calibration compared to the vendor driver). Adding support for this should be easy, but is not required for most applications. - channel #6 is connected to the SoCs internal temperature sensor. Adding support for this is probably not so easy since (based on the u-boot sources) most SoC versions are using different registers and algorithms for the conversion from "ADC value" to temperature. Supported by the hardware but currently not supported by the driver: - reading multiple channels at the same time (the hardware has a FIFO buffer which stores multiple results) - continuous sampling (this would require a way to enable this individually because otherwise the ADC would be drawing power constantly) - interrupt support (similar to the vendor driver this new driver is polling the results. It is unclear if the IRQ-mode is supported on older (Meson6 or Meson8) hardware as well or if there are any errata) [0] http://dn.odroid.com/S805/Datasheet/S805_Datasheet%20V0.8%2020150126.pdf [1] http://dn.odroid.com/S905/DataSheet/S905_Public_Datasheet_V1.1.4.pdf Signed-off-by: Martin Blumenstingl <martin.blumenstingl@googlemail.com> Tested-by: Neil Armstrong <narmstrong@baylibre.com> Signed-off-by: Jonathan Cameron <jic23@kernel.org>
2017-01-23 02:17:13 +08:00
};
MODULE_DEVICE_TABLE(of, meson_sar_adc_of_match);
static int meson_sar_adc_probe(struct platform_device *pdev)
{
const struct meson_sar_adc_data *match_data;
iio: adc: add a driver for the SAR ADC found in Amlogic Meson SoCs This adds support for the SAR (Successive Approximation Register) ADC on the Amlogic Meson SoCs. The code is based on the public S805 (Meson8b) and S905 (GXBB) datasheets (see [0] and [1]), as well as by reading (various versions of) the vendor driver and by inspecting the registers on the vendor kernels of my testing-hardware. Currently the GXBB, GXL and GXM SoCs are supported. GXBB hardware has 10-bit ADC resolution, while GXL and GXM have 12-bit ADC resolution. The code was written to support older SoCs (Meson8 and Meson8b) as well, but due to lack of actual testing-hardware no of_device_id was added for these. Two "features" from the vendor driver are currently missing: - the vendor driver uses channel #7 for calibration (this improves the accuracy of the results - in my tests the results were less than 3% off without calibration compared to the vendor driver). Adding support for this should be easy, but is not required for most applications. - channel #6 is connected to the SoCs internal temperature sensor. Adding support for this is probably not so easy since (based on the u-boot sources) most SoC versions are using different registers and algorithms for the conversion from "ADC value" to temperature. Supported by the hardware but currently not supported by the driver: - reading multiple channels at the same time (the hardware has a FIFO buffer which stores multiple results) - continuous sampling (this would require a way to enable this individually because otherwise the ADC would be drawing power constantly) - interrupt support (similar to the vendor driver this new driver is polling the results. It is unclear if the IRQ-mode is supported on older (Meson6 or Meson8) hardware as well or if there are any errata) [0] http://dn.odroid.com/S805/Datasheet/S805_Datasheet%20V0.8%2020150126.pdf [1] http://dn.odroid.com/S905/DataSheet/S905_Public_Datasheet_V1.1.4.pdf Signed-off-by: Martin Blumenstingl <martin.blumenstingl@googlemail.com> Tested-by: Neil Armstrong <narmstrong@baylibre.com> Signed-off-by: Jonathan Cameron <jic23@kernel.org>
2017-01-23 02:17:13 +08:00
struct meson_sar_adc_priv *priv;
struct device *dev = &pdev->dev;
iio: adc: add a driver for the SAR ADC found in Amlogic Meson SoCs This adds support for the SAR (Successive Approximation Register) ADC on the Amlogic Meson SoCs. The code is based on the public S805 (Meson8b) and S905 (GXBB) datasheets (see [0] and [1]), as well as by reading (various versions of) the vendor driver and by inspecting the registers on the vendor kernels of my testing-hardware. Currently the GXBB, GXL and GXM SoCs are supported. GXBB hardware has 10-bit ADC resolution, while GXL and GXM have 12-bit ADC resolution. The code was written to support older SoCs (Meson8 and Meson8b) as well, but due to lack of actual testing-hardware no of_device_id was added for these. Two "features" from the vendor driver are currently missing: - the vendor driver uses channel #7 for calibration (this improves the accuracy of the results - in my tests the results were less than 3% off without calibration compared to the vendor driver). Adding support for this should be easy, but is not required for most applications. - channel #6 is connected to the SoCs internal temperature sensor. Adding support for this is probably not so easy since (based on the u-boot sources) most SoC versions are using different registers and algorithms for the conversion from "ADC value" to temperature. Supported by the hardware but currently not supported by the driver: - reading multiple channels at the same time (the hardware has a FIFO buffer which stores multiple results) - continuous sampling (this would require a way to enable this individually because otherwise the ADC would be drawing power constantly) - interrupt support (similar to the vendor driver this new driver is polling the results. It is unclear if the IRQ-mode is supported on older (Meson6 or Meson8) hardware as well or if there are any errata) [0] http://dn.odroid.com/S805/Datasheet/S805_Datasheet%20V0.8%2020150126.pdf [1] http://dn.odroid.com/S905/DataSheet/S905_Public_Datasheet_V1.1.4.pdf Signed-off-by: Martin Blumenstingl <martin.blumenstingl@googlemail.com> Tested-by: Neil Armstrong <narmstrong@baylibre.com> Signed-off-by: Jonathan Cameron <jic23@kernel.org>
2017-01-23 02:17:13 +08:00
struct iio_dev *indio_dev;
void __iomem *base;
int irq, ret;
iio: adc: add a driver for the SAR ADC found in Amlogic Meson SoCs This adds support for the SAR (Successive Approximation Register) ADC on the Amlogic Meson SoCs. The code is based on the public S805 (Meson8b) and S905 (GXBB) datasheets (see [0] and [1]), as well as by reading (various versions of) the vendor driver and by inspecting the registers on the vendor kernels of my testing-hardware. Currently the GXBB, GXL and GXM SoCs are supported. GXBB hardware has 10-bit ADC resolution, while GXL and GXM have 12-bit ADC resolution. The code was written to support older SoCs (Meson8 and Meson8b) as well, but due to lack of actual testing-hardware no of_device_id was added for these. Two "features" from the vendor driver are currently missing: - the vendor driver uses channel #7 for calibration (this improves the accuracy of the results - in my tests the results were less than 3% off without calibration compared to the vendor driver). Adding support for this should be easy, but is not required for most applications. - channel #6 is connected to the SoCs internal temperature sensor. Adding support for this is probably not so easy since (based on the u-boot sources) most SoC versions are using different registers and algorithms for the conversion from "ADC value" to temperature. Supported by the hardware but currently not supported by the driver: - reading multiple channels at the same time (the hardware has a FIFO buffer which stores multiple results) - continuous sampling (this would require a way to enable this individually because otherwise the ADC would be drawing power constantly) - interrupt support (similar to the vendor driver this new driver is polling the results. It is unclear if the IRQ-mode is supported on older (Meson6 or Meson8) hardware as well or if there are any errata) [0] http://dn.odroid.com/S805/Datasheet/S805_Datasheet%20V0.8%2020150126.pdf [1] http://dn.odroid.com/S905/DataSheet/S905_Public_Datasheet_V1.1.4.pdf Signed-off-by: Martin Blumenstingl <martin.blumenstingl@googlemail.com> Tested-by: Neil Armstrong <narmstrong@baylibre.com> Signed-off-by: Jonathan Cameron <jic23@kernel.org>
2017-01-23 02:17:13 +08:00
indio_dev = devm_iio_device_alloc(dev, sizeof(*priv));
if (!indio_dev)
return dev_err_probe(dev, -ENOMEM, "failed allocating iio device\n");
iio: adc: add a driver for the SAR ADC found in Amlogic Meson SoCs This adds support for the SAR (Successive Approximation Register) ADC on the Amlogic Meson SoCs. The code is based on the public S805 (Meson8b) and S905 (GXBB) datasheets (see [0] and [1]), as well as by reading (various versions of) the vendor driver and by inspecting the registers on the vendor kernels of my testing-hardware. Currently the GXBB, GXL and GXM SoCs are supported. GXBB hardware has 10-bit ADC resolution, while GXL and GXM have 12-bit ADC resolution. The code was written to support older SoCs (Meson8 and Meson8b) as well, but due to lack of actual testing-hardware no of_device_id was added for these. Two "features" from the vendor driver are currently missing: - the vendor driver uses channel #7 for calibration (this improves the accuracy of the results - in my tests the results were less than 3% off without calibration compared to the vendor driver). Adding support for this should be easy, but is not required for most applications. - channel #6 is connected to the SoCs internal temperature sensor. Adding support for this is probably not so easy since (based on the u-boot sources) most SoC versions are using different registers and algorithms for the conversion from "ADC value" to temperature. Supported by the hardware but currently not supported by the driver: - reading multiple channels at the same time (the hardware has a FIFO buffer which stores multiple results) - continuous sampling (this would require a way to enable this individually because otherwise the ADC would be drawing power constantly) - interrupt support (similar to the vendor driver this new driver is polling the results. It is unclear if the IRQ-mode is supported on older (Meson6 or Meson8) hardware as well or if there are any errata) [0] http://dn.odroid.com/S805/Datasheet/S805_Datasheet%20V0.8%2020150126.pdf [1] http://dn.odroid.com/S905/DataSheet/S905_Public_Datasheet_V1.1.4.pdf Signed-off-by: Martin Blumenstingl <martin.blumenstingl@googlemail.com> Tested-by: Neil Armstrong <narmstrong@baylibre.com> Signed-off-by: Jonathan Cameron <jic23@kernel.org>
2017-01-23 02:17:13 +08:00
priv = iio_priv(indio_dev);
init_completion(&priv->done);
iio: adc: add a driver for the SAR ADC found in Amlogic Meson SoCs This adds support for the SAR (Successive Approximation Register) ADC on the Amlogic Meson SoCs. The code is based on the public S805 (Meson8b) and S905 (GXBB) datasheets (see [0] and [1]), as well as by reading (various versions of) the vendor driver and by inspecting the registers on the vendor kernels of my testing-hardware. Currently the GXBB, GXL and GXM SoCs are supported. GXBB hardware has 10-bit ADC resolution, while GXL and GXM have 12-bit ADC resolution. The code was written to support older SoCs (Meson8 and Meson8b) as well, but due to lack of actual testing-hardware no of_device_id was added for these. Two "features" from the vendor driver are currently missing: - the vendor driver uses channel #7 for calibration (this improves the accuracy of the results - in my tests the results were less than 3% off without calibration compared to the vendor driver). Adding support for this should be easy, but is not required for most applications. - channel #6 is connected to the SoCs internal temperature sensor. Adding support for this is probably not so easy since (based on the u-boot sources) most SoC versions are using different registers and algorithms for the conversion from "ADC value" to temperature. Supported by the hardware but currently not supported by the driver: - reading multiple channels at the same time (the hardware has a FIFO buffer which stores multiple results) - continuous sampling (this would require a way to enable this individually because otherwise the ADC would be drawing power constantly) - interrupt support (similar to the vendor driver this new driver is polling the results. It is unclear if the IRQ-mode is supported on older (Meson6 or Meson8) hardware as well or if there are any errata) [0] http://dn.odroid.com/S805/Datasheet/S805_Datasheet%20V0.8%2020150126.pdf [1] http://dn.odroid.com/S905/DataSheet/S905_Public_Datasheet_V1.1.4.pdf Signed-off-by: Martin Blumenstingl <martin.blumenstingl@googlemail.com> Tested-by: Neil Armstrong <narmstrong@baylibre.com> Signed-off-by: Jonathan Cameron <jic23@kernel.org>
2017-01-23 02:17:13 +08:00
match_data = of_device_get_match_data(dev);
if (!match_data)
return dev_err_probe(dev, -ENODEV, "failed to get match data\n");
priv->param = match_data->param;
iio: adc: add a driver for the SAR ADC found in Amlogic Meson SoCs This adds support for the SAR (Successive Approximation Register) ADC on the Amlogic Meson SoCs. The code is based on the public S805 (Meson8b) and S905 (GXBB) datasheets (see [0] and [1]), as well as by reading (various versions of) the vendor driver and by inspecting the registers on the vendor kernels of my testing-hardware. Currently the GXBB, GXL and GXM SoCs are supported. GXBB hardware has 10-bit ADC resolution, while GXL and GXM have 12-bit ADC resolution. The code was written to support older SoCs (Meson8 and Meson8b) as well, but due to lack of actual testing-hardware no of_device_id was added for these. Two "features" from the vendor driver are currently missing: - the vendor driver uses channel #7 for calibration (this improves the accuracy of the results - in my tests the results were less than 3% off without calibration compared to the vendor driver). Adding support for this should be easy, but is not required for most applications. - channel #6 is connected to the SoCs internal temperature sensor. Adding support for this is probably not so easy since (based on the u-boot sources) most SoC versions are using different registers and algorithms for the conversion from "ADC value" to temperature. Supported by the hardware but currently not supported by the driver: - reading multiple channels at the same time (the hardware has a FIFO buffer which stores multiple results) - continuous sampling (this would require a way to enable this individually because otherwise the ADC would be drawing power constantly) - interrupt support (similar to the vendor driver this new driver is polling the results. It is unclear if the IRQ-mode is supported on older (Meson6 or Meson8) hardware as well or if there are any errata) [0] http://dn.odroid.com/S805/Datasheet/S805_Datasheet%20V0.8%2020150126.pdf [1] http://dn.odroid.com/S905/DataSheet/S905_Public_Datasheet_V1.1.4.pdf Signed-off-by: Martin Blumenstingl <martin.blumenstingl@googlemail.com> Tested-by: Neil Armstrong <narmstrong@baylibre.com> Signed-off-by: Jonathan Cameron <jic23@kernel.org>
2017-01-23 02:17:13 +08:00
indio_dev->name = match_data->name;
iio: adc: add a driver for the SAR ADC found in Amlogic Meson SoCs This adds support for the SAR (Successive Approximation Register) ADC on the Amlogic Meson SoCs. The code is based on the public S805 (Meson8b) and S905 (GXBB) datasheets (see [0] and [1]), as well as by reading (various versions of) the vendor driver and by inspecting the registers on the vendor kernels of my testing-hardware. Currently the GXBB, GXL and GXM SoCs are supported. GXBB hardware has 10-bit ADC resolution, while GXL and GXM have 12-bit ADC resolution. The code was written to support older SoCs (Meson8 and Meson8b) as well, but due to lack of actual testing-hardware no of_device_id was added for these. Two "features" from the vendor driver are currently missing: - the vendor driver uses channel #7 for calibration (this improves the accuracy of the results - in my tests the results were less than 3% off without calibration compared to the vendor driver). Adding support for this should be easy, but is not required for most applications. - channel #6 is connected to the SoCs internal temperature sensor. Adding support for this is probably not so easy since (based on the u-boot sources) most SoC versions are using different registers and algorithms for the conversion from "ADC value" to temperature. Supported by the hardware but currently not supported by the driver: - reading multiple channels at the same time (the hardware has a FIFO buffer which stores multiple results) - continuous sampling (this would require a way to enable this individually because otherwise the ADC would be drawing power constantly) - interrupt support (similar to the vendor driver this new driver is polling the results. It is unclear if the IRQ-mode is supported on older (Meson6 or Meson8) hardware as well or if there are any errata) [0] http://dn.odroid.com/S805/Datasheet/S805_Datasheet%20V0.8%2020150126.pdf [1] http://dn.odroid.com/S905/DataSheet/S905_Public_Datasheet_V1.1.4.pdf Signed-off-by: Martin Blumenstingl <martin.blumenstingl@googlemail.com> Tested-by: Neil Armstrong <narmstrong@baylibre.com> Signed-off-by: Jonathan Cameron <jic23@kernel.org>
2017-01-23 02:17:13 +08:00
indio_dev->modes = INDIO_DIRECT_MODE;
indio_dev->info = &meson_sar_adc_iio_info;
base = devm_platform_ioremap_resource(pdev, 0);
iio: adc: add a driver for the SAR ADC found in Amlogic Meson SoCs This adds support for the SAR (Successive Approximation Register) ADC on the Amlogic Meson SoCs. The code is based on the public S805 (Meson8b) and S905 (GXBB) datasheets (see [0] and [1]), as well as by reading (various versions of) the vendor driver and by inspecting the registers on the vendor kernels of my testing-hardware. Currently the GXBB, GXL and GXM SoCs are supported. GXBB hardware has 10-bit ADC resolution, while GXL and GXM have 12-bit ADC resolution. The code was written to support older SoCs (Meson8 and Meson8b) as well, but due to lack of actual testing-hardware no of_device_id was added for these. Two "features" from the vendor driver are currently missing: - the vendor driver uses channel #7 for calibration (this improves the accuracy of the results - in my tests the results were less than 3% off without calibration compared to the vendor driver). Adding support for this should be easy, but is not required for most applications. - channel #6 is connected to the SoCs internal temperature sensor. Adding support for this is probably not so easy since (based on the u-boot sources) most SoC versions are using different registers and algorithms for the conversion from "ADC value" to temperature. Supported by the hardware but currently not supported by the driver: - reading multiple channels at the same time (the hardware has a FIFO buffer which stores multiple results) - continuous sampling (this would require a way to enable this individually because otherwise the ADC would be drawing power constantly) - interrupt support (similar to the vendor driver this new driver is polling the results. It is unclear if the IRQ-mode is supported on older (Meson6 or Meson8) hardware as well or if there are any errata) [0] http://dn.odroid.com/S805/Datasheet/S805_Datasheet%20V0.8%2020150126.pdf [1] http://dn.odroid.com/S905/DataSheet/S905_Public_Datasheet_V1.1.4.pdf Signed-off-by: Martin Blumenstingl <martin.blumenstingl@googlemail.com> Tested-by: Neil Armstrong <narmstrong@baylibre.com> Signed-off-by: Jonathan Cameron <jic23@kernel.org>
2017-01-23 02:17:13 +08:00
if (IS_ERR(base))
return PTR_ERR(base);
priv->regmap = devm_regmap_init_mmio(dev, base, priv->param->regmap_config);
if (IS_ERR(priv->regmap))
return PTR_ERR(priv->regmap);
irq = irq_of_parse_and_map(dev->of_node, 0);
if (!irq)
return -EINVAL;
ret = devm_request_irq(dev, irq, meson_sar_adc_irq, IRQF_SHARED, dev_name(dev), indio_dev);
if (ret)
return ret;
priv->clkin = devm_clk_get(dev, "clkin");
if (IS_ERR(priv->clkin))
return dev_err_probe(dev, PTR_ERR(priv->clkin), "failed to get clkin\n");
iio: adc: add a driver for the SAR ADC found in Amlogic Meson SoCs This adds support for the SAR (Successive Approximation Register) ADC on the Amlogic Meson SoCs. The code is based on the public S805 (Meson8b) and S905 (GXBB) datasheets (see [0] and [1]), as well as by reading (various versions of) the vendor driver and by inspecting the registers on the vendor kernels of my testing-hardware. Currently the GXBB, GXL and GXM SoCs are supported. GXBB hardware has 10-bit ADC resolution, while GXL and GXM have 12-bit ADC resolution. The code was written to support older SoCs (Meson8 and Meson8b) as well, but due to lack of actual testing-hardware no of_device_id was added for these. Two "features" from the vendor driver are currently missing: - the vendor driver uses channel #7 for calibration (this improves the accuracy of the results - in my tests the results were less than 3% off without calibration compared to the vendor driver). Adding support for this should be easy, but is not required for most applications. - channel #6 is connected to the SoCs internal temperature sensor. Adding support for this is probably not so easy since (based on the u-boot sources) most SoC versions are using different registers and algorithms for the conversion from "ADC value" to temperature. Supported by the hardware but currently not supported by the driver: - reading multiple channels at the same time (the hardware has a FIFO buffer which stores multiple results) - continuous sampling (this would require a way to enable this individually because otherwise the ADC would be drawing power constantly) - interrupt support (similar to the vendor driver this new driver is polling the results. It is unclear if the IRQ-mode is supported on older (Meson6 or Meson8) hardware as well or if there are any errata) [0] http://dn.odroid.com/S805/Datasheet/S805_Datasheet%20V0.8%2020150126.pdf [1] http://dn.odroid.com/S905/DataSheet/S905_Public_Datasheet_V1.1.4.pdf Signed-off-by: Martin Blumenstingl <martin.blumenstingl@googlemail.com> Tested-by: Neil Armstrong <narmstrong@baylibre.com> Signed-off-by: Jonathan Cameron <jic23@kernel.org>
2017-01-23 02:17:13 +08:00
priv->core_clk = devm_clk_get_enabled(dev, "core");
if (IS_ERR(priv->core_clk))
return dev_err_probe(dev, PTR_ERR(priv->core_clk), "failed to get core clk\n");
iio: adc: add a driver for the SAR ADC found in Amlogic Meson SoCs This adds support for the SAR (Successive Approximation Register) ADC on the Amlogic Meson SoCs. The code is based on the public S805 (Meson8b) and S905 (GXBB) datasheets (see [0] and [1]), as well as by reading (various versions of) the vendor driver and by inspecting the registers on the vendor kernels of my testing-hardware. Currently the GXBB, GXL and GXM SoCs are supported. GXBB hardware has 10-bit ADC resolution, while GXL and GXM have 12-bit ADC resolution. The code was written to support older SoCs (Meson8 and Meson8b) as well, but due to lack of actual testing-hardware no of_device_id was added for these. Two "features" from the vendor driver are currently missing: - the vendor driver uses channel #7 for calibration (this improves the accuracy of the results - in my tests the results were less than 3% off without calibration compared to the vendor driver). Adding support for this should be easy, but is not required for most applications. - channel #6 is connected to the SoCs internal temperature sensor. Adding support for this is probably not so easy since (based on the u-boot sources) most SoC versions are using different registers and algorithms for the conversion from "ADC value" to temperature. Supported by the hardware but currently not supported by the driver: - reading multiple channels at the same time (the hardware has a FIFO buffer which stores multiple results) - continuous sampling (this would require a way to enable this individually because otherwise the ADC would be drawing power constantly) - interrupt support (similar to the vendor driver this new driver is polling the results. It is unclear if the IRQ-mode is supported on older (Meson6 or Meson8) hardware as well or if there are any errata) [0] http://dn.odroid.com/S805/Datasheet/S805_Datasheet%20V0.8%2020150126.pdf [1] http://dn.odroid.com/S905/DataSheet/S905_Public_Datasheet_V1.1.4.pdf Signed-off-by: Martin Blumenstingl <martin.blumenstingl@googlemail.com> Tested-by: Neil Armstrong <narmstrong@baylibre.com> Signed-off-by: Jonathan Cameron <jic23@kernel.org>
2017-01-23 02:17:13 +08:00
priv->adc_clk = devm_clk_get_optional(dev, "adc_clk");
if (IS_ERR(priv->adc_clk))
return dev_err_probe(dev, PTR_ERR(priv->adc_clk), "failed to get adc clk\n");
iio: adc: add a driver for the SAR ADC found in Amlogic Meson SoCs This adds support for the SAR (Successive Approximation Register) ADC on the Amlogic Meson SoCs. The code is based on the public S805 (Meson8b) and S905 (GXBB) datasheets (see [0] and [1]), as well as by reading (various versions of) the vendor driver and by inspecting the registers on the vendor kernels of my testing-hardware. Currently the GXBB, GXL and GXM SoCs are supported. GXBB hardware has 10-bit ADC resolution, while GXL and GXM have 12-bit ADC resolution. The code was written to support older SoCs (Meson8 and Meson8b) as well, but due to lack of actual testing-hardware no of_device_id was added for these. Two "features" from the vendor driver are currently missing: - the vendor driver uses channel #7 for calibration (this improves the accuracy of the results - in my tests the results were less than 3% off without calibration compared to the vendor driver). Adding support for this should be easy, but is not required for most applications. - channel #6 is connected to the SoCs internal temperature sensor. Adding support for this is probably not so easy since (based on the u-boot sources) most SoC versions are using different registers and algorithms for the conversion from "ADC value" to temperature. Supported by the hardware but currently not supported by the driver: - reading multiple channels at the same time (the hardware has a FIFO buffer which stores multiple results) - continuous sampling (this would require a way to enable this individually because otherwise the ADC would be drawing power constantly) - interrupt support (similar to the vendor driver this new driver is polling the results. It is unclear if the IRQ-mode is supported on older (Meson6 or Meson8) hardware as well or if there are any errata) [0] http://dn.odroid.com/S805/Datasheet/S805_Datasheet%20V0.8%2020150126.pdf [1] http://dn.odroid.com/S905/DataSheet/S905_Public_Datasheet_V1.1.4.pdf Signed-off-by: Martin Blumenstingl <martin.blumenstingl@googlemail.com> Tested-by: Neil Armstrong <narmstrong@baylibre.com> Signed-off-by: Jonathan Cameron <jic23@kernel.org>
2017-01-23 02:17:13 +08:00
priv->adc_sel_clk = devm_clk_get_optional(dev, "adc_sel");
if (IS_ERR(priv->adc_sel_clk))
return dev_err_probe(dev, PTR_ERR(priv->adc_sel_clk), "failed to get adc_sel clk\n");
iio: adc: add a driver for the SAR ADC found in Amlogic Meson SoCs This adds support for the SAR (Successive Approximation Register) ADC on the Amlogic Meson SoCs. The code is based on the public S805 (Meson8b) and S905 (GXBB) datasheets (see [0] and [1]), as well as by reading (various versions of) the vendor driver and by inspecting the registers on the vendor kernels of my testing-hardware. Currently the GXBB, GXL and GXM SoCs are supported. GXBB hardware has 10-bit ADC resolution, while GXL and GXM have 12-bit ADC resolution. The code was written to support older SoCs (Meson8 and Meson8b) as well, but due to lack of actual testing-hardware no of_device_id was added for these. Two "features" from the vendor driver are currently missing: - the vendor driver uses channel #7 for calibration (this improves the accuracy of the results - in my tests the results were less than 3% off without calibration compared to the vendor driver). Adding support for this should be easy, but is not required for most applications. - channel #6 is connected to the SoCs internal temperature sensor. Adding support for this is probably not so easy since (based on the u-boot sources) most SoC versions are using different registers and algorithms for the conversion from "ADC value" to temperature. Supported by the hardware but currently not supported by the driver: - reading multiple channels at the same time (the hardware has a FIFO buffer which stores multiple results) - continuous sampling (this would require a way to enable this individually because otherwise the ADC would be drawing power constantly) - interrupt support (similar to the vendor driver this new driver is polling the results. It is unclear if the IRQ-mode is supported on older (Meson6 or Meson8) hardware as well or if there are any errata) [0] http://dn.odroid.com/S805/Datasheet/S805_Datasheet%20V0.8%2020150126.pdf [1] http://dn.odroid.com/S905/DataSheet/S905_Public_Datasheet_V1.1.4.pdf Signed-off-by: Martin Blumenstingl <martin.blumenstingl@googlemail.com> Tested-by: Neil Armstrong <narmstrong@baylibre.com> Signed-off-by: Jonathan Cameron <jic23@kernel.org>
2017-01-23 02:17:13 +08:00
/* on pre-GXBB SoCs the SAR ADC itself provides the ADC clock: */
if (!priv->adc_clk) {
ret = meson_sar_adc_clk_init(indio_dev, base);
if (ret)
return ret;
}
priv->vref = devm_regulator_get(dev, "vref");
if (IS_ERR(priv->vref))
return dev_err_probe(dev, PTR_ERR(priv->vref), "failed to get vref regulator\n");
iio: adc: add a driver for the SAR ADC found in Amlogic Meson SoCs This adds support for the SAR (Successive Approximation Register) ADC on the Amlogic Meson SoCs. The code is based on the public S805 (Meson8b) and S905 (GXBB) datasheets (see [0] and [1]), as well as by reading (various versions of) the vendor driver and by inspecting the registers on the vendor kernels of my testing-hardware. Currently the GXBB, GXL and GXM SoCs are supported. GXBB hardware has 10-bit ADC resolution, while GXL and GXM have 12-bit ADC resolution. The code was written to support older SoCs (Meson8 and Meson8b) as well, but due to lack of actual testing-hardware no of_device_id was added for these. Two "features" from the vendor driver are currently missing: - the vendor driver uses channel #7 for calibration (this improves the accuracy of the results - in my tests the results were less than 3% off without calibration compared to the vendor driver). Adding support for this should be easy, but is not required for most applications. - channel #6 is connected to the SoCs internal temperature sensor. Adding support for this is probably not so easy since (based on the u-boot sources) most SoC versions are using different registers and algorithms for the conversion from "ADC value" to temperature. Supported by the hardware but currently not supported by the driver: - reading multiple channels at the same time (the hardware has a FIFO buffer which stores multiple results) - continuous sampling (this would require a way to enable this individually because otherwise the ADC would be drawing power constantly) - interrupt support (similar to the vendor driver this new driver is polling the results. It is unclear if the IRQ-mode is supported on older (Meson6 or Meson8) hardware as well or if there are any errata) [0] http://dn.odroid.com/S805/Datasheet/S805_Datasheet%20V0.8%2020150126.pdf [1] http://dn.odroid.com/S905/DataSheet/S905_Public_Datasheet_V1.1.4.pdf Signed-off-by: Martin Blumenstingl <martin.blumenstingl@googlemail.com> Tested-by: Neil Armstrong <narmstrong@baylibre.com> Signed-off-by: Jonathan Cameron <jic23@kernel.org>
2017-01-23 02:17:13 +08:00
priv->calibscale = MILLION;
iio: adc: meson-saradc: add support for the chip's temperature sensor Channel 6 of the SAR ADC can be switched between two inputs: SAR_ADC_CH6 input (an actual pad on the SoC) and the signal from the temperature sensor inside the SoC. To get usable results from the temperature sensor we need to read the corresponding calibration data from the eFuse and pass it to the SAR ADC registers. If the temperature sensor is not calibrated (the eFuse data contains a bit for this) then the driver will only register the iio_chan_spec's for voltage measurements. This only enables the temperature sensor for the Meson8 SoC. Meson8b and Meson8m2 SoCs can be supported in the future as well but we first need a way to pass the fifth TSC (temperature sensor coefficient) bit to the HHI register area (apart from that the infrastructure as already implemented for Meson8 can be used). On the 64-bit SoCs (GXBB, GXL and GXM) the temperature sensor inside SAR ADC is firmware-controlled (by BL30, we can simply use the SCPI hwmon driver to get the chip temperature). To keep the devicetree interface backwards compatible we simply skip the temperature sensor initialization if no eFuse nvmem cell is passed via devicetree. The public documentation for the SAR ADC IP block does not explain how to use the registers to read the temperature. The logic from this patch is based on reading and understanding Amlogic's GPL kernel sources. Signed-off-by: Martin Blumenstingl <martin.blumenstingl@googlemail.com> Signed-off-by: Jonathan Cameron <Jonathan.Cameron@huawei.com>
2018-11-04 07:10:24 +08:00
if (priv->param->temperature_trimming_bits) {
ret = meson_sar_adc_temp_sensor_init(indio_dev);
if (ret)
return ret;
}
if (priv->temperature_sensor_calibrated) {
indio_dev->channels = meson_sar_adc_and_temp_iio_channels;
indio_dev->num_channels =
ARRAY_SIZE(meson_sar_adc_and_temp_iio_channels);
} else {
indio_dev->channels = meson_sar_adc_iio_channels;
indio_dev->num_channels =
ARRAY_SIZE(meson_sar_adc_iio_channels);
}
iio: adc: add a driver for the SAR ADC found in Amlogic Meson SoCs This adds support for the SAR (Successive Approximation Register) ADC on the Amlogic Meson SoCs. The code is based on the public S805 (Meson8b) and S905 (GXBB) datasheets (see [0] and [1]), as well as by reading (various versions of) the vendor driver and by inspecting the registers on the vendor kernels of my testing-hardware. Currently the GXBB, GXL and GXM SoCs are supported. GXBB hardware has 10-bit ADC resolution, while GXL and GXM have 12-bit ADC resolution. The code was written to support older SoCs (Meson8 and Meson8b) as well, but due to lack of actual testing-hardware no of_device_id was added for these. Two "features" from the vendor driver are currently missing: - the vendor driver uses channel #7 for calibration (this improves the accuracy of the results - in my tests the results were less than 3% off without calibration compared to the vendor driver). Adding support for this should be easy, but is not required for most applications. - channel #6 is connected to the SoCs internal temperature sensor. Adding support for this is probably not so easy since (based on the u-boot sources) most SoC versions are using different registers and algorithms for the conversion from "ADC value" to temperature. Supported by the hardware but currently not supported by the driver: - reading multiple channels at the same time (the hardware has a FIFO buffer which stores multiple results) - continuous sampling (this would require a way to enable this individually because otherwise the ADC would be drawing power constantly) - interrupt support (similar to the vendor driver this new driver is polling the results. It is unclear if the IRQ-mode is supported on older (Meson6 or Meson8) hardware as well or if there are any errata) [0] http://dn.odroid.com/S805/Datasheet/S805_Datasheet%20V0.8%2020150126.pdf [1] http://dn.odroid.com/S905/DataSheet/S905_Public_Datasheet_V1.1.4.pdf Signed-off-by: Martin Blumenstingl <martin.blumenstingl@googlemail.com> Tested-by: Neil Armstrong <narmstrong@baylibre.com> Signed-off-by: Jonathan Cameron <jic23@kernel.org>
2017-01-23 02:17:13 +08:00
ret = meson_sar_adc_init(indio_dev);
if (ret)
goto err;
mutex_init(&priv->lock);
iio: adc: add a driver for the SAR ADC found in Amlogic Meson SoCs This adds support for the SAR (Successive Approximation Register) ADC on the Amlogic Meson SoCs. The code is based on the public S805 (Meson8b) and S905 (GXBB) datasheets (see [0] and [1]), as well as by reading (various versions of) the vendor driver and by inspecting the registers on the vendor kernels of my testing-hardware. Currently the GXBB, GXL and GXM SoCs are supported. GXBB hardware has 10-bit ADC resolution, while GXL and GXM have 12-bit ADC resolution. The code was written to support older SoCs (Meson8 and Meson8b) as well, but due to lack of actual testing-hardware no of_device_id was added for these. Two "features" from the vendor driver are currently missing: - the vendor driver uses channel #7 for calibration (this improves the accuracy of the results - in my tests the results were less than 3% off without calibration compared to the vendor driver). Adding support for this should be easy, but is not required for most applications. - channel #6 is connected to the SoCs internal temperature sensor. Adding support for this is probably not so easy since (based on the u-boot sources) most SoC versions are using different registers and algorithms for the conversion from "ADC value" to temperature. Supported by the hardware but currently not supported by the driver: - reading multiple channels at the same time (the hardware has a FIFO buffer which stores multiple results) - continuous sampling (this would require a way to enable this individually because otherwise the ADC would be drawing power constantly) - interrupt support (similar to the vendor driver this new driver is polling the results. It is unclear if the IRQ-mode is supported on older (Meson6 or Meson8) hardware as well or if there are any errata) [0] http://dn.odroid.com/S805/Datasheet/S805_Datasheet%20V0.8%2020150126.pdf [1] http://dn.odroid.com/S905/DataSheet/S905_Public_Datasheet_V1.1.4.pdf Signed-off-by: Martin Blumenstingl <martin.blumenstingl@googlemail.com> Tested-by: Neil Armstrong <narmstrong@baylibre.com> Signed-off-by: Jonathan Cameron <jic23@kernel.org>
2017-01-23 02:17:13 +08:00
ret = meson_sar_adc_hw_enable(indio_dev);
if (ret)
goto err;
ret = meson_sar_adc_calib(indio_dev);
if (ret)
dev_warn(dev, "calibration failed\n");
iio: adc: add a driver for the SAR ADC found in Amlogic Meson SoCs This adds support for the SAR (Successive Approximation Register) ADC on the Amlogic Meson SoCs. The code is based on the public S805 (Meson8b) and S905 (GXBB) datasheets (see [0] and [1]), as well as by reading (various versions of) the vendor driver and by inspecting the registers on the vendor kernels of my testing-hardware. Currently the GXBB, GXL and GXM SoCs are supported. GXBB hardware has 10-bit ADC resolution, while GXL and GXM have 12-bit ADC resolution. The code was written to support older SoCs (Meson8 and Meson8b) as well, but due to lack of actual testing-hardware no of_device_id was added for these. Two "features" from the vendor driver are currently missing: - the vendor driver uses channel #7 for calibration (this improves the accuracy of the results - in my tests the results were less than 3% off without calibration compared to the vendor driver). Adding support for this should be easy, but is not required for most applications. - channel #6 is connected to the SoCs internal temperature sensor. Adding support for this is probably not so easy since (based on the u-boot sources) most SoC versions are using different registers and algorithms for the conversion from "ADC value" to temperature. Supported by the hardware but currently not supported by the driver: - reading multiple channels at the same time (the hardware has a FIFO buffer which stores multiple results) - continuous sampling (this would require a way to enable this individually because otherwise the ADC would be drawing power constantly) - interrupt support (similar to the vendor driver this new driver is polling the results. It is unclear if the IRQ-mode is supported on older (Meson6 or Meson8) hardware as well or if there are any errata) [0] http://dn.odroid.com/S805/Datasheet/S805_Datasheet%20V0.8%2020150126.pdf [1] http://dn.odroid.com/S905/DataSheet/S905_Public_Datasheet_V1.1.4.pdf Signed-off-by: Martin Blumenstingl <martin.blumenstingl@googlemail.com> Tested-by: Neil Armstrong <narmstrong@baylibre.com> Signed-off-by: Jonathan Cameron <jic23@kernel.org>
2017-01-23 02:17:13 +08:00
platform_set_drvdata(pdev, indio_dev);
ret = iio_device_register(indio_dev);
if (ret)
goto err_hw;
return 0;
err_hw:
meson_sar_adc_hw_disable(indio_dev);
err:
return ret;
}
static int meson_sar_adc_remove(struct platform_device *pdev)
{
struct iio_dev *indio_dev = platform_get_drvdata(pdev);
iio_device_unregister(indio_dev);
meson_sar_adc_hw_disable(indio_dev);
return 0;
iio: adc: add a driver for the SAR ADC found in Amlogic Meson SoCs This adds support for the SAR (Successive Approximation Register) ADC on the Amlogic Meson SoCs. The code is based on the public S805 (Meson8b) and S905 (GXBB) datasheets (see [0] and [1]), as well as by reading (various versions of) the vendor driver and by inspecting the registers on the vendor kernels of my testing-hardware. Currently the GXBB, GXL and GXM SoCs are supported. GXBB hardware has 10-bit ADC resolution, while GXL and GXM have 12-bit ADC resolution. The code was written to support older SoCs (Meson8 and Meson8b) as well, but due to lack of actual testing-hardware no of_device_id was added for these. Two "features" from the vendor driver are currently missing: - the vendor driver uses channel #7 for calibration (this improves the accuracy of the results - in my tests the results were less than 3% off without calibration compared to the vendor driver). Adding support for this should be easy, but is not required for most applications. - channel #6 is connected to the SoCs internal temperature sensor. Adding support for this is probably not so easy since (based on the u-boot sources) most SoC versions are using different registers and algorithms for the conversion from "ADC value" to temperature. Supported by the hardware but currently not supported by the driver: - reading multiple channels at the same time (the hardware has a FIFO buffer which stores multiple results) - continuous sampling (this would require a way to enable this individually because otherwise the ADC would be drawing power constantly) - interrupt support (similar to the vendor driver this new driver is polling the results. It is unclear if the IRQ-mode is supported on older (Meson6 or Meson8) hardware as well or if there are any errata) [0] http://dn.odroid.com/S805/Datasheet/S805_Datasheet%20V0.8%2020150126.pdf [1] http://dn.odroid.com/S905/DataSheet/S905_Public_Datasheet_V1.1.4.pdf Signed-off-by: Martin Blumenstingl <martin.blumenstingl@googlemail.com> Tested-by: Neil Armstrong <narmstrong@baylibre.com> Signed-off-by: Jonathan Cameron <jic23@kernel.org>
2017-01-23 02:17:13 +08:00
}
static int meson_sar_adc_suspend(struct device *dev)
iio: adc: add a driver for the SAR ADC found in Amlogic Meson SoCs This adds support for the SAR (Successive Approximation Register) ADC on the Amlogic Meson SoCs. The code is based on the public S805 (Meson8b) and S905 (GXBB) datasheets (see [0] and [1]), as well as by reading (various versions of) the vendor driver and by inspecting the registers on the vendor kernels of my testing-hardware. Currently the GXBB, GXL and GXM SoCs are supported. GXBB hardware has 10-bit ADC resolution, while GXL and GXM have 12-bit ADC resolution. The code was written to support older SoCs (Meson8 and Meson8b) as well, but due to lack of actual testing-hardware no of_device_id was added for these. Two "features" from the vendor driver are currently missing: - the vendor driver uses channel #7 for calibration (this improves the accuracy of the results - in my tests the results were less than 3% off without calibration compared to the vendor driver). Adding support for this should be easy, but is not required for most applications. - channel #6 is connected to the SoCs internal temperature sensor. Adding support for this is probably not so easy since (based on the u-boot sources) most SoC versions are using different registers and algorithms for the conversion from "ADC value" to temperature. Supported by the hardware but currently not supported by the driver: - reading multiple channels at the same time (the hardware has a FIFO buffer which stores multiple results) - continuous sampling (this would require a way to enable this individually because otherwise the ADC would be drawing power constantly) - interrupt support (similar to the vendor driver this new driver is polling the results. It is unclear if the IRQ-mode is supported on older (Meson6 or Meson8) hardware as well or if there are any errata) [0] http://dn.odroid.com/S805/Datasheet/S805_Datasheet%20V0.8%2020150126.pdf [1] http://dn.odroid.com/S905/DataSheet/S905_Public_Datasheet_V1.1.4.pdf Signed-off-by: Martin Blumenstingl <martin.blumenstingl@googlemail.com> Tested-by: Neil Armstrong <narmstrong@baylibre.com> Signed-off-by: Jonathan Cameron <jic23@kernel.org>
2017-01-23 02:17:13 +08:00
{
struct iio_dev *indio_dev = dev_get_drvdata(dev);
struct meson_sar_adc_priv *priv = iio_priv(indio_dev);
iio: adc: add a driver for the SAR ADC found in Amlogic Meson SoCs This adds support for the SAR (Successive Approximation Register) ADC on the Amlogic Meson SoCs. The code is based on the public S805 (Meson8b) and S905 (GXBB) datasheets (see [0] and [1]), as well as by reading (various versions of) the vendor driver and by inspecting the registers on the vendor kernels of my testing-hardware. Currently the GXBB, GXL and GXM SoCs are supported. GXBB hardware has 10-bit ADC resolution, while GXL and GXM have 12-bit ADC resolution. The code was written to support older SoCs (Meson8 and Meson8b) as well, but due to lack of actual testing-hardware no of_device_id was added for these. Two "features" from the vendor driver are currently missing: - the vendor driver uses channel #7 for calibration (this improves the accuracy of the results - in my tests the results were less than 3% off without calibration compared to the vendor driver). Adding support for this should be easy, but is not required for most applications. - channel #6 is connected to the SoCs internal temperature sensor. Adding support for this is probably not so easy since (based on the u-boot sources) most SoC versions are using different registers and algorithms for the conversion from "ADC value" to temperature. Supported by the hardware but currently not supported by the driver: - reading multiple channels at the same time (the hardware has a FIFO buffer which stores multiple results) - continuous sampling (this would require a way to enable this individually because otherwise the ADC would be drawing power constantly) - interrupt support (similar to the vendor driver this new driver is polling the results. It is unclear if the IRQ-mode is supported on older (Meson6 or Meson8) hardware as well or if there are any errata) [0] http://dn.odroid.com/S805/Datasheet/S805_Datasheet%20V0.8%2020150126.pdf [1] http://dn.odroid.com/S905/DataSheet/S905_Public_Datasheet_V1.1.4.pdf Signed-off-by: Martin Blumenstingl <martin.blumenstingl@googlemail.com> Tested-by: Neil Armstrong <narmstrong@baylibre.com> Signed-off-by: Jonathan Cameron <jic23@kernel.org>
2017-01-23 02:17:13 +08:00
meson_sar_adc_hw_disable(indio_dev);
clk_disable_unprepare(priv->core_clk);
return 0;
iio: adc: add a driver for the SAR ADC found in Amlogic Meson SoCs This adds support for the SAR (Successive Approximation Register) ADC on the Amlogic Meson SoCs. The code is based on the public S805 (Meson8b) and S905 (GXBB) datasheets (see [0] and [1]), as well as by reading (various versions of) the vendor driver and by inspecting the registers on the vendor kernels of my testing-hardware. Currently the GXBB, GXL and GXM SoCs are supported. GXBB hardware has 10-bit ADC resolution, while GXL and GXM have 12-bit ADC resolution. The code was written to support older SoCs (Meson8 and Meson8b) as well, but due to lack of actual testing-hardware no of_device_id was added for these. Two "features" from the vendor driver are currently missing: - the vendor driver uses channel #7 for calibration (this improves the accuracy of the results - in my tests the results were less than 3% off without calibration compared to the vendor driver). Adding support for this should be easy, but is not required for most applications. - channel #6 is connected to the SoCs internal temperature sensor. Adding support for this is probably not so easy since (based on the u-boot sources) most SoC versions are using different registers and algorithms for the conversion from "ADC value" to temperature. Supported by the hardware but currently not supported by the driver: - reading multiple channels at the same time (the hardware has a FIFO buffer which stores multiple results) - continuous sampling (this would require a way to enable this individually because otherwise the ADC would be drawing power constantly) - interrupt support (similar to the vendor driver this new driver is polling the results. It is unclear if the IRQ-mode is supported on older (Meson6 or Meson8) hardware as well or if there are any errata) [0] http://dn.odroid.com/S805/Datasheet/S805_Datasheet%20V0.8%2020150126.pdf [1] http://dn.odroid.com/S905/DataSheet/S905_Public_Datasheet_V1.1.4.pdf Signed-off-by: Martin Blumenstingl <martin.blumenstingl@googlemail.com> Tested-by: Neil Armstrong <narmstrong@baylibre.com> Signed-off-by: Jonathan Cameron <jic23@kernel.org>
2017-01-23 02:17:13 +08:00
}
static int meson_sar_adc_resume(struct device *dev)
iio: adc: add a driver for the SAR ADC found in Amlogic Meson SoCs This adds support for the SAR (Successive Approximation Register) ADC on the Amlogic Meson SoCs. The code is based on the public S805 (Meson8b) and S905 (GXBB) datasheets (see [0] and [1]), as well as by reading (various versions of) the vendor driver and by inspecting the registers on the vendor kernels of my testing-hardware. Currently the GXBB, GXL and GXM SoCs are supported. GXBB hardware has 10-bit ADC resolution, while GXL and GXM have 12-bit ADC resolution. The code was written to support older SoCs (Meson8 and Meson8b) as well, but due to lack of actual testing-hardware no of_device_id was added for these. Two "features" from the vendor driver are currently missing: - the vendor driver uses channel #7 for calibration (this improves the accuracy of the results - in my tests the results were less than 3% off without calibration compared to the vendor driver). Adding support for this should be easy, but is not required for most applications. - channel #6 is connected to the SoCs internal temperature sensor. Adding support for this is probably not so easy since (based on the u-boot sources) most SoC versions are using different registers and algorithms for the conversion from "ADC value" to temperature. Supported by the hardware but currently not supported by the driver: - reading multiple channels at the same time (the hardware has a FIFO buffer which stores multiple results) - continuous sampling (this would require a way to enable this individually because otherwise the ADC would be drawing power constantly) - interrupt support (similar to the vendor driver this new driver is polling the results. It is unclear if the IRQ-mode is supported on older (Meson6 or Meson8) hardware as well or if there are any errata) [0] http://dn.odroid.com/S805/Datasheet/S805_Datasheet%20V0.8%2020150126.pdf [1] http://dn.odroid.com/S905/DataSheet/S905_Public_Datasheet_V1.1.4.pdf Signed-off-by: Martin Blumenstingl <martin.blumenstingl@googlemail.com> Tested-by: Neil Armstrong <narmstrong@baylibre.com> Signed-off-by: Jonathan Cameron <jic23@kernel.org>
2017-01-23 02:17:13 +08:00
{
struct iio_dev *indio_dev = dev_get_drvdata(dev);
struct meson_sar_adc_priv *priv = iio_priv(indio_dev);
int ret;
ret = clk_prepare_enable(priv->core_clk);
if (ret) {
dev_err(dev, "failed to enable core clk\n");
return ret;
}
iio: adc: add a driver for the SAR ADC found in Amlogic Meson SoCs This adds support for the SAR (Successive Approximation Register) ADC on the Amlogic Meson SoCs. The code is based on the public S805 (Meson8b) and S905 (GXBB) datasheets (see [0] and [1]), as well as by reading (various versions of) the vendor driver and by inspecting the registers on the vendor kernels of my testing-hardware. Currently the GXBB, GXL and GXM SoCs are supported. GXBB hardware has 10-bit ADC resolution, while GXL and GXM have 12-bit ADC resolution. The code was written to support older SoCs (Meson8 and Meson8b) as well, but due to lack of actual testing-hardware no of_device_id was added for these. Two "features" from the vendor driver are currently missing: - the vendor driver uses channel #7 for calibration (this improves the accuracy of the results - in my tests the results were less than 3% off without calibration compared to the vendor driver). Adding support for this should be easy, but is not required for most applications. - channel #6 is connected to the SoCs internal temperature sensor. Adding support for this is probably not so easy since (based on the u-boot sources) most SoC versions are using different registers and algorithms for the conversion from "ADC value" to temperature. Supported by the hardware but currently not supported by the driver: - reading multiple channels at the same time (the hardware has a FIFO buffer which stores multiple results) - continuous sampling (this would require a way to enable this individually because otherwise the ADC would be drawing power constantly) - interrupt support (similar to the vendor driver this new driver is polling the results. It is unclear if the IRQ-mode is supported on older (Meson6 or Meson8) hardware as well or if there are any errata) [0] http://dn.odroid.com/S805/Datasheet/S805_Datasheet%20V0.8%2020150126.pdf [1] http://dn.odroid.com/S905/DataSheet/S905_Public_Datasheet_V1.1.4.pdf Signed-off-by: Martin Blumenstingl <martin.blumenstingl@googlemail.com> Tested-by: Neil Armstrong <narmstrong@baylibre.com> Signed-off-by: Jonathan Cameron <jic23@kernel.org>
2017-01-23 02:17:13 +08:00
return meson_sar_adc_hw_enable(indio_dev);
}
static DEFINE_SIMPLE_DEV_PM_OPS(meson_sar_adc_pm_ops,
meson_sar_adc_suspend, meson_sar_adc_resume);
iio: adc: add a driver for the SAR ADC found in Amlogic Meson SoCs This adds support for the SAR (Successive Approximation Register) ADC on the Amlogic Meson SoCs. The code is based on the public S805 (Meson8b) and S905 (GXBB) datasheets (see [0] and [1]), as well as by reading (various versions of) the vendor driver and by inspecting the registers on the vendor kernels of my testing-hardware. Currently the GXBB, GXL and GXM SoCs are supported. GXBB hardware has 10-bit ADC resolution, while GXL and GXM have 12-bit ADC resolution. The code was written to support older SoCs (Meson8 and Meson8b) as well, but due to lack of actual testing-hardware no of_device_id was added for these. Two "features" from the vendor driver are currently missing: - the vendor driver uses channel #7 for calibration (this improves the accuracy of the results - in my tests the results were less than 3% off without calibration compared to the vendor driver). Adding support for this should be easy, but is not required for most applications. - channel #6 is connected to the SoCs internal temperature sensor. Adding support for this is probably not so easy since (based on the u-boot sources) most SoC versions are using different registers and algorithms for the conversion from "ADC value" to temperature. Supported by the hardware but currently not supported by the driver: - reading multiple channels at the same time (the hardware has a FIFO buffer which stores multiple results) - continuous sampling (this would require a way to enable this individually because otherwise the ADC would be drawing power constantly) - interrupt support (similar to the vendor driver this new driver is polling the results. It is unclear if the IRQ-mode is supported on older (Meson6 or Meson8) hardware as well or if there are any errata) [0] http://dn.odroid.com/S805/Datasheet/S805_Datasheet%20V0.8%2020150126.pdf [1] http://dn.odroid.com/S905/DataSheet/S905_Public_Datasheet_V1.1.4.pdf Signed-off-by: Martin Blumenstingl <martin.blumenstingl@googlemail.com> Tested-by: Neil Armstrong <narmstrong@baylibre.com> Signed-off-by: Jonathan Cameron <jic23@kernel.org>
2017-01-23 02:17:13 +08:00
static struct platform_driver meson_sar_adc_driver = {
.probe = meson_sar_adc_probe,
.remove = meson_sar_adc_remove,
.driver = {
.name = "meson-saradc",
.of_match_table = meson_sar_adc_of_match,
.pm = pm_sleep_ptr(&meson_sar_adc_pm_ops),
iio: adc: add a driver for the SAR ADC found in Amlogic Meson SoCs This adds support for the SAR (Successive Approximation Register) ADC on the Amlogic Meson SoCs. The code is based on the public S805 (Meson8b) and S905 (GXBB) datasheets (see [0] and [1]), as well as by reading (various versions of) the vendor driver and by inspecting the registers on the vendor kernels of my testing-hardware. Currently the GXBB, GXL and GXM SoCs are supported. GXBB hardware has 10-bit ADC resolution, while GXL and GXM have 12-bit ADC resolution. The code was written to support older SoCs (Meson8 and Meson8b) as well, but due to lack of actual testing-hardware no of_device_id was added for these. Two "features" from the vendor driver are currently missing: - the vendor driver uses channel #7 for calibration (this improves the accuracy of the results - in my tests the results were less than 3% off without calibration compared to the vendor driver). Adding support for this should be easy, but is not required for most applications. - channel #6 is connected to the SoCs internal temperature sensor. Adding support for this is probably not so easy since (based on the u-boot sources) most SoC versions are using different registers and algorithms for the conversion from "ADC value" to temperature. Supported by the hardware but currently not supported by the driver: - reading multiple channels at the same time (the hardware has a FIFO buffer which stores multiple results) - continuous sampling (this would require a way to enable this individually because otherwise the ADC would be drawing power constantly) - interrupt support (similar to the vendor driver this new driver is polling the results. It is unclear if the IRQ-mode is supported on older (Meson6 or Meson8) hardware as well or if there are any errata) [0] http://dn.odroid.com/S805/Datasheet/S805_Datasheet%20V0.8%2020150126.pdf [1] http://dn.odroid.com/S905/DataSheet/S905_Public_Datasheet_V1.1.4.pdf Signed-off-by: Martin Blumenstingl <martin.blumenstingl@googlemail.com> Tested-by: Neil Armstrong <narmstrong@baylibre.com> Signed-off-by: Jonathan Cameron <jic23@kernel.org>
2017-01-23 02:17:13 +08:00
},
};
module_platform_driver(meson_sar_adc_driver);
MODULE_AUTHOR("Martin Blumenstingl <martin.blumenstingl@googlemail.com>");
MODULE_DESCRIPTION("Amlogic Meson SAR ADC driver");
MODULE_LICENSE("GPL v2");