Commit Graph

47 Commits

Author SHA1 Message Date
David Frey 1691d4ca70 iio: chemical: bme680: Remove field value defines
Remove BME680_RUN_GAS_EN_BIT and BME680_NB_CONV_0_VAL field value
definitions because the fields are simply boolean and integer
respectively.

Signed-off-by: David Frey <dpfrey@gmail.com>
Reviewed-by: Himanshu Jha <himanshujha199640@gmail.com>
Tested-by: Himanshu Jha <himanshujha199640@gmail.com>
Signed-off-by: Jonathan Cameron <Jonathan.Cameron@huawei.com>
2018-08-25 09:13:45 +01:00
Himanshu Jha 892e62fab4 iio: chemical: bme680: Add check for val2 in the write_raw function
val2 is responsible for the floating part of the number to be
written to the device. We don't need the floating part
while writing the oversampling ratio for BME680 since the
available oversampling ratios are pure natural numbers.

So, add a sanity check to make sure val2 is 0.

Signed-off-by: Himanshu Jha <himanshujha199640@gmail.com>
Signed-off-by: Jonathan Cameron <Jonathan.Cameron@huawei.com>
2018-08-19 20:07:25 +01:00
David Frey 79fd571b7a iio: chemical: bme680: simplify oversampling handling
Temperature, pressure and humidity all expose and oversampling setting
that works in the same way.  Provide common handling for the
oversampling sysfs attributes.

Signed-off-by: David Frey <dpfrey@gmail.com>
Reviewed-by: Himanshu Jha <himanshujha199640@gmail.com>
Tested-by: Himanshu Jha <himanshujha199640@gmail.com>
Signed-off-by: Jonathan Cameron <Jonathan.Cameron@huawei.com>
2018-08-19 17:11:42 +01:00
David Frey 3dcb60cd92 iio: chemical: bme680: use FIELD_GET macro
Use the FIELD_GET macro instead of explicit mask and shift.

Signed-off-by: David Frey <dpfrey@gmail.com>
Reviewed-by: Himanshu Jha <himanshujha199640@gmail.com>
Tested-by: Himanshu Jha <himanshujha199640@gmail.com>
Signed-off-by: Jonathan Cameron <Jonathan.Cameron@huawei.com>
2018-08-19 17:08:25 +01:00
David Frey 8d3032c369 iio: chemical: bme680: use GENMASK macro
Replace hardcoded bit masks with GENMASK macro

Signed-off-by: David Frey <dpfrey@gmail.com>
Reviewed-by: Himanshu Jha <himanshujha199640@gmail.com>
Tested-by: Himanshu Jha <himanshujha199640@gmail.com>
Signed-off-by: Jonathan Cameron <Jonathan.Cameron@huawei.com>
2018-08-19 17:06:53 +01:00
David Frey a24b4d70c7 iio: chemical: bme680: change MSK->MASK in #defines
Convert all defines to use "MASK" instead of a mix of "MSK" and "MASK"

Signed-off-by: David Frey <dpfrey@gmail.com>
Reviewed-by: Himanshu Jha <himanshujha199640@gmail.com>
Tested-by: Himanshu Jha <himanshujha199640@gmail.com>
Signed-off-by: Jonathan Cameron <Jonathan.Cameron@huawei.com>
2018-08-19 17:04:43 +01:00
David Frey 70f1cbddb2 iio: chemical: bme680: indent #defines consistently
Signed-off-by: David Frey <dpfrey@gmail.com>
Reviewed-by: Himanshu Jha <himanshujha199640@gmail.com>
Tested-by: Himanshu Jha <himanshujha199640@gmail.com>
Signed-off-by: Jonathan Cameron <Jonathan.Cameron@huawei.com>
2018-08-19 17:00:52 +01:00
David Frey 6784ba340a iio: chemical: bme680: cleanup bme680_read_calib formatting
Use the full 80 char width to reduce the number of lines taken
by function calls.

Remove blank lines where it aids clarity by bringing together related
code blocks (such as read hi and low bytes and then combine them into
one value).

Signed-off-by: David Frey <dpfrey@gmail.com>
Reviewed-by: Himanshu Jha <himanshujha199640@gmail.com>
Tested-by: Himanshu Jha <himanshujha199640@gmail.com>
Signed-off-by: Jonathan Cameron <Jonathan.Cameron@huawei.com>
2018-08-19 16:58:45 +01:00
David Frey 8a0ae7d83a iio: chemical: bme680: use clamp macro
Signed-off-by: David Frey <dpfrey@gmail.com>
Reviewed-by: Himanshu Jha <himanshujha199640@gmail.com>
Tested-by: Himanshu Jha <himanshujha199640@gmail.com>
Signed-off-by: Jonathan Cameron <Jonathan.Cameron@huawei.com>
2018-08-19 16:46:28 +01:00
Colin Ian King 5e45729608 iio: chemical: fix spelling mistake "failted" -> "failed"
fix spelling mistake in dev_err error message text

Signed-off-by: Colin Ian King <colin.king@canonical.com>
Reviewed-by: Himanshu Jha <himanshujha199640@gmail.com>
Signed-off-by: Jonathan Cameron <Jonathan.Cameron@huawei.com>
2018-08-03 22:33:48 +01:00
Himanshu Jha 1b3bd85927 iio: chemical: Add support for Bosch BME680 sensor
Bosch BME680 is a 4-in-1 sensor with temperature, pressure, humidity
and gas sensing capability. It supports both I2C and SPI communication
protocol for effective data communication.

The device supports two modes:

1. Sleep mode
2. Forced mode

The measurements only takes place when forced mode is triggered and a
single TPHG cycle is performed by the sensor. The sensor automatically
goes to sleep after afterwards.

The device has various calibration constants/parameters programmed into
devices' non-volatile memory(NVM) during production and can't be altered
by the user. These constants are used in the compensation functions to
get the required compensated readings along with the raw data. The
compensation functions/algorithms are provided by Bosch Sensortec GmbH
via their API[1]. As these don't change during the measurement cycle,
therefore we read and store them at the probe. The default configs
supplied by Bosch are also set at probe.

0-day tested with build success.

GSoC-2018: https://summerofcode.withgoogle.com/projects/#6691473790074880
Mentor: Daniel Baluta
[1] https://github.com/BoschSensortec/BME680_driver
Datasheet:
https://ae-bst.resource.bosch.com/media/_tech/media/datasheets/BST-BME680-DS001-00.pdf

Note from Jonathan: The compensation functions are 'interesting' and
could do with a tidy up in future.  However, they work so we can leave that
for another day.

Cc: Daniel Baluta <daniel.baluta@nxp.com>
Signed-off-by: Himanshu Jha <himanshujha199640@gmail.com>
Signed-off-by: Jonathan Cameron <Jonathan.Cameron@huawei.com>
2018-07-28 11:38:46 +01:00
Greg Kroah-Hartman 6a8b25abf1 1st round of IIO new device support, features and cleanup for the 4.18 cycle
A nice mix this time of excellent cleanups (many to send drivers
 speeding toward staging graduations) and new drivers / device support.
 A good part of this is Brian Masney's never ending task on the tsl2x7x
 driver.  The end is in sight so hopefully we'll get that one out of
 staging very soon!
 
 New device support
 * AD5686
   - Support AD5685R (was wrongly present as AD5685)
   - Support AD5672R, AD5676, AD5676, AD5684R and AD5686R 4 and 8 channel
     SPI DACs with various precisions.
   - Support AD5671R, AD5675R, AD5694, AD5694R, AD5695R, AD5696 and AD5696R
     I2C DACs with various percisions and numbers of channels.
 * Analog front end rescale driver - New driver.
   - Support current sensing usings a shunt resistor.
   - Support simple voltage dividers.
   - support simple current sense amplifiers.
 * TI dac5571
   - New driver and device bindings supporting:
     dac5571, dac6571, dac7571, dac5574, dac6574, dac7574,
     dac5573, dac6573 and dac7573
 * Meson-adc
   - Support for Meson AXG with DT bindings.
 * mpu6050
   - Support the mpu9255 which only requires additional WHOAMI entry and
     compatible string.
 * st_lsm6dsx
   - Support for lsm330dlc combinded accelerometer and gyro sensors with
     DT bindings.
 * stm32_adc
   - Add support for STM32MP1 with bindings.
 
 Staging graduations
 * adis16201 after some excelent cleanup by Himanshu Jha.
 * adis16029 after some excelent cleanup by Shreeya Patel.
 
 New features:
 * ABI docs
   - Add core ABI docs for angle channels.
 * inv_mpu6050
   - Provide support for the full range of interrupts the device
     supports.
 * st_accel
   - Add SMO8840 ACPI ID seen in the wild on some Lenovo machines.
 * stx104
   - Provide a multiple gpio get function.
 
 Cleanups / Minor fixes
 * core
   - Use new nested structure support to improve kernel-doc.
 * ad2s1200
   - Use be16_to_cpup instead of opencoding.
 * ad5686
   - Indentation tidy up.
   - Switch to SPDX
   - Refactor to allow various numbers of channels.
   - Refactor to separate core and SPI specific support, prior to
     addition of i2c equivalent devices.
 * ad7606
   - Use drvdata directly from device rather than boucing via the
     platform_device structure.
 * ad7746
   - Replace opencoded byte swapped i2c calls with _swapped variants.
   - White space and line break readability improvements.
   - Reorder includes and variable declarations where appropriate.
 * ad7791
   - Changes to the AD ADC library used by this driver took in the
     sampling frequency.  This lead to be the wrong path being the one
     tied to the resulting attribute, so it didn't work, and a warning
     to be printed.
 * ad7780
   - Remove apparent support for sampling frequency control on devices
     that don't support changing the sampling attributes.
 * ade7854
   - Fix a read of the wrong number of bits.
   - Improve error handling on i2c read/write errors.
   - Rework i2c and spi code to reduce duplication.
 * adis16201 (staging)
   - Improve meaning inherent in some macro names by adding units etc
     where relevant.
   - Adjust comments to improve detail and drop the irrelevant.
   - Rename register address definitions definitions to add a _REG
     postfix, clearly separating them from field definitions. Reorganize
     the definitions to group register address and fields.
   - Use sign_extend32 rather than open coding.
   - Reverse Xmas tree ordering where appropriate and align function args.
   - Remove unused headers.
   - Use GENMASK where appropriate instead of open coding.
 * adis16209 (staging)
   - Indent field definitions to visually separate them from
     register address definitions.
   - Use reverse xmas tree ordering where appropriate.
   - Add some whitespace where it will help readability.
   - Drop some unused headers.
   - Use GENMASK where appropriate.
 * ad2s1200
   - Drop unnecessary includes and reorder alphabetically.
   - Reverse xmas tree and blank line cleanups.
 * atlas-ph-sensor
   - Use msleep instead of usleep_range where the precise value doesn't
     matter and the delays are long.
 * bcm150
   - Drop transaction splitting as core now handles it.
 * cros_ec
   - Move the shared header to the include/iio/common directory.
     This brings it inline with the other multiple type devices.
   - Use drvdata directly from device rather than boucing via the
     platform_device structure.
 * hid-sensors
   - Use drvdata directly from device rather than boucing via the
     platform_device structure.
 * inv_mpu6050
   - Clear out a second function definition for the same function.
   - Don't flush fifo when the iio buffer is full but just drop excess
     data.
   - Tidy up set_power_itg and ensure it is used in the right places.
   - Use set_power_itg rather than opencoding it again in the i2c mux
     control.
   - Make sure error paths disable the power if undoing power on.
   - Used managed devm_ functions during probe. Delete remove function.
   - Refactor to pull raw data read out of read_raw function.
   - Simplify data reading error paths.
   - Only enable the i2c mux for chips with the i2c aux bus (not icm20608)
   - Fix a potential deadlock due to varying lock ordering.
   - Fix an issue where first sample from gyro after enabling is unstable
     by dropping the first sample.
   - Fix an issue where the user_ctrl register is incorrectly overwritten.
   - Tidy up some grammar and spelling minor issus.
 * mcp320x
   - Use vendor compatible strings.
 * mcp4018
   - Switch to using i2c .probe_new.
 * mcp4351
   - switch to using i2c .probe_new.
 * meson-adc
   - rework handing on common ADC platform data so it can be shared
     across multiple families of SoCs.
 * sca3000
   - Fix an error handling path if the ring configure fails.
 * st_lsm6dsx
   - Fix a wrong fifo threshold mask (no actual effect)
 * stm32-dfsdm
   - Style fixes and cleanups.
   - Check filter ID is in range and check spi-max-frequency.
 * tsl2x7x (staging)
   - Drop some unnecessary function calls, unused variables and
     unnecessary local variables.
   - Fix wrong interrupt type.
   - Avoid unnecessary double clear of interrupt.
   - Simplify proximity calibration call which did various things
     unrelated to actually calibrating.
   - Separate control of the proximity and ALS interrupts.
   - Improve consistency of logging.
   - Separate ALS and proximity persistence settings as they have
     separate hardware controls.
   - Tidy up variable ordering.
   - Add Brian to copyright notice given consider work on this driver.
   - Take advantage of hardware support for I2C address auto increment.
   - Combine individuaal enable and period attributes for the two
     directions on the threshold events into a single value as the
     hardware doesn't separate them.
   - Move integration_time* attributes from light channel to
     intensity value as they effect the intensity readings directly
     and the light reading only indirectly.  Hence this better
     reflects reality. Also move the calibscale_available.
   - Avoid returning an error in the IRQ handler.
   - Hard code the reg value in _clear_interrupts as it only takes
     one value in the code.   Result is the function has little
     purpose so opencode the two remaining i2c_smbus_write_byte
     calls.
   - Drop some unnecessary checking of the chip status register.
   - Tidy up return path in _write_interrupt_config.
   - Tidy up the ID verification code.
   - Move the power and diode settings defines into the header as these
     are needed for platform data configuration.
   - Various renames and comment cleanups for consistency and clarity.
   - Use actual device defaults for default startup settings.
   - SPDX
   - Add some range sanity checking to sysfs attribute writes.
   - Don't provide event interfaces if the interrupt line isn't available.
   - Use IIO_CONST_ATTR macro for calibscale_available as it's a constant
     string.
   - Fix the integration time and lux equations.
   - Make device IDs explicit index values in the device_channel_config array.
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Merge tag 'iio-for-4.18a' of git://git.kernel.org/pub/scm/linux/kernel/git/jic23/iio into staging-next

Jonathan writes:

1st round of IIO new device support, features and cleanup for the 4.18 cycle

A nice mix this time of excellent cleanups (many to send drivers
speeding toward staging graduations) and new drivers / device support.
A good part of this is Brian Masney's never ending task on the tsl2x7x
driver.  The end is in sight so hopefully we'll get that one out of
staging very soon!

New device support
* AD5686
  - Support AD5685R (was wrongly present as AD5685)
  - Support AD5672R, AD5676, AD5676, AD5684R and AD5686R 4 and 8 channel
    SPI DACs with various precisions.
  - Support AD5671R, AD5675R, AD5694, AD5694R, AD5695R, AD5696 and AD5696R
    I2C DACs with various percisions and numbers of channels.
* Analog front end rescale driver - New driver.
  - Support current sensing usings a shunt resistor.
  - Support simple voltage dividers.
  - support simple current sense amplifiers.
* TI dac5571
  - New driver and device bindings supporting:
    dac5571, dac6571, dac7571, dac5574, dac6574, dac7574,
    dac5573, dac6573 and dac7573
* Meson-adc
  - Support for Meson AXG with DT bindings.
* mpu6050
  - Support the mpu9255 which only requires additional WHOAMI entry and
    compatible string.
* st_lsm6dsx
  - Support for lsm330dlc combinded accelerometer and gyro sensors with
    DT bindings.
* stm32_adc
  - Add support for STM32MP1 with bindings.

Staging graduations
* adis16201 after some excelent cleanup by Himanshu Jha.
* adis16029 after some excelent cleanup by Shreeya Patel.

New features:
* ABI docs
  - Add core ABI docs for angle channels.
* inv_mpu6050
  - Provide support for the full range of interrupts the device
    supports.
* st_accel
  - Add SMO8840 ACPI ID seen in the wild on some Lenovo machines.
* stx104
  - Provide a multiple gpio get function.

Cleanups / Minor fixes
* core
  - Use new nested structure support to improve kernel-doc.
* ad2s1200
  - Use be16_to_cpup instead of opencoding.
* ad5686
  - Indentation tidy up.
  - Switch to SPDX
  - Refactor to allow various numbers of channels.
  - Refactor to separate core and SPI specific support, prior to
    addition of i2c equivalent devices.
* ad7606
  - Use drvdata directly from device rather than boucing via the
    platform_device structure.
* ad7746
  - Replace opencoded byte swapped i2c calls with _swapped variants.
  - White space and line break readability improvements.
  - Reorder includes and variable declarations where appropriate.
* ad7791
  - Changes to the AD ADC library used by this driver took in the
    sampling frequency.  This lead to be the wrong path being the one
    tied to the resulting attribute, so it didn't work, and a warning
    to be printed.
* ad7780
  - Remove apparent support for sampling frequency control on devices
    that don't support changing the sampling attributes.
* ade7854
  - Fix a read of the wrong number of bits.
  - Improve error handling on i2c read/write errors.
  - Rework i2c and spi code to reduce duplication.
* adis16201 (staging)
  - Improve meaning inherent in some macro names by adding units etc
    where relevant.
  - Adjust comments to improve detail and drop the irrelevant.
  - Rename register address definitions definitions to add a _REG
    postfix, clearly separating them from field definitions. Reorganize
    the definitions to group register address and fields.
  - Use sign_extend32 rather than open coding.
  - Reverse Xmas tree ordering where appropriate and align function args.
  - Remove unused headers.
  - Use GENMASK where appropriate instead of open coding.
* adis16209 (staging)
  - Indent field definitions to visually separate them from
    register address definitions.
  - Use reverse xmas tree ordering where appropriate.
  - Add some whitespace where it will help readability.
  - Drop some unused headers.
  - Use GENMASK where appropriate.
* ad2s1200
  - Drop unnecessary includes and reorder alphabetically.
  - Reverse xmas tree and blank line cleanups.
* atlas-ph-sensor
  - Use msleep instead of usleep_range where the precise value doesn't
    matter and the delays are long.
* bcm150
  - Drop transaction splitting as core now handles it.
* cros_ec
  - Move the shared header to the include/iio/common directory.
    This brings it inline with the other multiple type devices.
  - Use drvdata directly from device rather than boucing via the
    platform_device structure.
* hid-sensors
  - Use drvdata directly from device rather than boucing via the
    platform_device structure.
* inv_mpu6050
  - Clear out a second function definition for the same function.
  - Don't flush fifo when the iio buffer is full but just drop excess
    data.
  - Tidy up set_power_itg and ensure it is used in the right places.
  - Use set_power_itg rather than opencoding it again in the i2c mux
    control.
  - Make sure error paths disable the power if undoing power on.
  - Used managed devm_ functions during probe. Delete remove function.
  - Refactor to pull raw data read out of read_raw function.
  - Simplify data reading error paths.
  - Only enable the i2c mux for chips with the i2c aux bus (not icm20608)
  - Fix a potential deadlock due to varying lock ordering.
  - Fix an issue where first sample from gyro after enabling is unstable
    by dropping the first sample.
  - Fix an issue where the user_ctrl register is incorrectly overwritten.
  - Tidy up some grammar and spelling minor issus.
* mcp320x
  - Use vendor compatible strings.
* mcp4018
  - Switch to using i2c .probe_new.
* mcp4351
  - switch to using i2c .probe_new.
* meson-adc
  - rework handing on common ADC platform data so it can be shared
    across multiple families of SoCs.
* sca3000
  - Fix an error handling path if the ring configure fails.
* st_lsm6dsx
  - Fix a wrong fifo threshold mask (no actual effect)
* stm32-dfsdm
  - Style fixes and cleanups.
  - Check filter ID is in range and check spi-max-frequency.
* tsl2x7x (staging)
  - Drop some unnecessary function calls, unused variables and
    unnecessary local variables.
  - Fix wrong interrupt type.
  - Avoid unnecessary double clear of interrupt.
  - Simplify proximity calibration call which did various things
    unrelated to actually calibrating.
  - Separate control of the proximity and ALS interrupts.
  - Improve consistency of logging.
  - Separate ALS and proximity persistence settings as they have
    separate hardware controls.
  - Tidy up variable ordering.
  - Add Brian to copyright notice given consider work on this driver.
  - Take advantage of hardware support for I2C address auto increment.
  - Combine individuaal enable and period attributes for the two
    directions on the threshold events into a single value as the
    hardware doesn't separate them.
  - Move integration_time* attributes from light channel to
    intensity value as they effect the intensity readings directly
    and the light reading only indirectly.  Hence this better
    reflects reality. Also move the calibscale_available.
  - Avoid returning an error in the IRQ handler.
  - Hard code the reg value in _clear_interrupts as it only takes
    one value in the code.   Result is the function has little
    purpose so opencode the two remaining i2c_smbus_write_byte
    calls.
  - Drop some unnecessary checking of the chip status register.
  - Tidy up return path in _write_interrupt_config.
  - Tidy up the ID verification code.
  - Move the power and diode settings defines into the header as these
    are needed for platform data configuration.
  - Various renames and comment cleanups for consistency and clarity.
  - Use actual device defaults for default startup settings.
  - SPDX
  - Add some range sanity checking to sysfs attribute writes.
  - Don't provide event interfaces if the interrupt line isn't available.
  - Use IIO_CONST_ATTR macro for calibscale_available as it's a constant
    string.
  - Fix the integration time and lux equations.
  - Make device IDs explicit index values in the device_channel_config array.
2018-05-11 09:50:04 +02:00
Matt Ranostay 02112260ac iio: chemical: atlas-ph-sensor: use msleep() for long uncritical delays
usleep_range() uses hrtimers and provides no advantage over msleep()
for larger delays.

Cc: Nicholas Mc Guire <hofrat@osadl.org>
Link: http://lkml.org/lkml/2017/1/11/377
Signed-off-by: Matt Ranostay <matt.ranostay@konsulko.com>
Reviewed-by: Nicholas Mc Guire <hofrat@osadl.org>
Signed-off-by: Jonathan Cameron <Jonathan.Cameron@huawei.com>
2018-04-15 18:37:26 +01:00
Greg Kroah-Hartman a0306db6e5 Merge 4.16-rc7 into staging-next
We want the IIO and staging driver fixes in here as well.

Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2018-03-28 13:33:37 +02:00
Richard Lai b91e146c38 iio: chemical: ccs811: Corrected firmware boot/application mode transition
CCS811 has different I2C register maps in boot and application mode. When
CCS811 is in boot mode, register APP_START (0xF4) is used to transit the
firmware state from boot to application mode. However, APP_START is not a
valid register location when CCS811 is in application mode (refer to
"CCS811 Bootloader Register Map" and "CCS811 Application Register Map" in
CCS811 datasheet). The driver should not attempt to perform a write to
APP_START while CCS811 is in application mode, as this is not a valid or
documented register location.

When prob function is being called, the driver assumes the CCS811 sensor
is in boot mode, and attempts to perform a write to APP_START. Although
CCS811 powers-up in boot mode, it may have already been transited to
application mode by previous instances, e.g. unload and reload device
driver by the system, or explicitly by user. Depending on the system
design, CCS811 sensor may be permanently connected to system power source
rather than power controlled by GPIO, hence it is possible that the sensor
is never power reset, thus the firmware could be in either boot or
application mode at any given time when driver prob function is being
called.

This patch checks the STATUS register before attempting to send a write to
APP_START. Only if the firmware is not in application mode and has valid
firmware application loaded, then it will continue to start transiting the
firmware boot to application mode.

Signed-off-by: Richard Lai <richard@richardman.com>
Cc: <Stable@vger.kernel.org>
Signed-off-by: Jonathan Cameron <Jonathan.Cameron@huawei.com>
2018-02-24 12:12:19 +00:00
Richard Lai 4c73b809a9 iio: chemical: ccs811: Renamed resistance member in ccs811_reading struct
The resistance member in ccs811_reading struct is an unsigned 16-bit
integer variable used to store RAW_DATA register bytes read from CCS811.
It is kind of misleading to name this struct member as resistance.

About the RAW_DATA register bytes, the CCS811 datasheet states that:
-----
Two byte read only register which contains the latest readings from the
sense resistor.

The most significant 6 bits of the Byte 0 contain the value of the current
through the sensor (0μA to 63μA).

The lower 10 bits contain (as computed from the ADC) the readings of the
voltage across the sensor with the selected current (1023 = 1.65V)"
-----

Hence, the RAW_DATA register byte contains information about electric
current and voltage of the CCS811 sensor. Calling this struct member
'resistance' is kind of misleading, although both electric current and
voltage are needed to calculate the electrical resistance of the sensor
using Ohm's law, V = I x R, in which a new channel type of IIO_RESISTANCE
may be added to the driver in the future.

Signed-off-by: Richard Lai <richard@richardman.com>

Signed-off-by: Jonathan Cameron <Jonathan.Cameron@huawei.com>
2018-02-24 11:04:28 +00:00
Matt Ranostay d6ad805844 iio: add SPDX identifier for various drivers
Add GPLv2+ SPDX identifier and update email for author's drivers.

Signed-off-by: Matt Ranostay <matt.ranostay@konsulko.com>
Signed-off-by: Jonathan Cameron <Jonathan.Cameron@huawei.com>
2018-02-18 11:55:19 +00:00
Richard Lai f0ef941a62 iio: chemical: ccs811: Typo correction in HW_ID_VALUE constant define naming
This particular constant was named with prefix "CCS881", which should be
"CCS811" instead, just like the rest of constant names in the file, as this
driver implementation is for AMS CCS811 sensor. "CCS881" could literally be
referring to another sensor product unrelated to AMS CCS811 sensor.

Signed-off-by: Richard Lai <richard@richardman.com>
Signed-off-by: Jonathan Cameron <Jonathan.Cameron@huawei.com>
2018-02-17 14:11:18 +00:00
Narcisa Ana Maria Vasile 8f114acd4e iio: chemical: ccs811: Fix output of IIO_CONCENTRATION channels
in_concentration_raw should report, according to sysfs-bus-iio documentation,
a "Raw (unscaled no offset etc.) percentage reading of a substance."

Modify scale to convert from ppm/ppb to percentage:
1 ppm = 0.0001%
1 ppb = 0.0000001%

There is no offset needed to convert the ppm/ppb to percentage,
so remove offset from IIO_CONCENTRATION (IIO_MOD_CO2) channel.

Cc'd stable to reduce chance of userspace breakage in the long
run as we fix this wrong bit of ABI usage.

Signed-off-by: Narcisa Ana Maria Vasile <narcisaanamaria12@gmail.com>
Cc: <Stable@vger.kernel.org>
Reviewed-by: Matt Ranostay <matt.ranostay@konsulko.com>
Signed-off-by: Jonathan Cameron <Jonathan.Cameron@huawei.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2018-01-08 16:03:44 +01:00
Narcisa Ana Maria Vasile f1f065d7ac iio: chemical: ccs811: Add support for data ready trigger
Add data ready trigger for hardware interrupts that signal
new, available measurement samples.

Cc: Daniel Baluta <daniel.baluta@gmail.com>
Cc: Alison Schofield <amsfield22@gmail.com>
Signed-off-by: Narcisa Ana Maria Vasile <narcisaanamaria12@gmail.com>
Signed-off-by: Jonathan Cameron <Jonathan.Cameron@huawei.com>
2017-09-24 12:34:36 +01:00
Jonathan Cameron 254f3a6364 iio:chemical: drop assign iio_info.driver_module and iio_trigger_ops.owner
The equivalent of both of these are now done via macro magic when
the relevant register calls are made.  The actual structure
elements will shortly go away.

Signed-off-by: Jonathan Cameron <Jonathan.Cameron@huawei.com>
Reviewed-by: Lars-Peter Clausen <lars@metafoo.de>
2017-08-22 21:25:20 +01:00
Narcisa Ana Maria Vasile 283d26917a iio: chemical: ccs811: Add triggered buffer support
A software trigger such as hrtimer can be used to capture the data
that will be stored in the buffer.

Cc: Daniel Baluta <daniel.baluta@gmail.com>
Cc: Alison Schofield <amsfield22@gmail.com>
Signed-off-by: Narcisa Ana Maria Vasile <narcisaanamaria12@gmail.com>
Signed-off-by: Jonathan Cameron <Jonathan.Cameron@huawei.com>
2017-08-18 08:08:02 +01:00
Narcisa Ana Maria Vasile a94c24a712 iio: chemical: ccs811: Add support for AMS CCS811 VOC sensor
Add support for CCS811 VOC sensor. This patch adds support
for reading current and voltage across the sensor and TVOC
and equivalent CO2 values.

Scale and offset values have been computed according to datasheet:
    - For current: raw value is in microamps
        => 0.001 scale to convert to milliamps
    - For voltage: 1.65V = 1023, therefore 1650mV = 1023
        => 1650.0/1023 = 1.612903 scale to convert to millivolts
    - For eCO2: raw value range is from 400ppm to 8192ppm.
        => (val - 400) * (100 - 0) / (8192 - 400) + 0 =
           (val - 400) * 0.01283367 => offset: -400, scale = 0.012834
           to get a percentage value
    -For TVOC: raw value range is from 0ppb to 1187ppb.
        => (val - 0) * 100 / (1187 - 0) + 0 = val * 0.0842459 =>
            scale = 0.084246 for getting a percentage value

Cc: Daniel Baluta <daniel.baluta@gmail.com>
Cc: Alison Schofield <amsfield22@gmail.com>
Signed-off-by: Narcisa Ana Maria Vasile <narcisaanamaria12@gmail.com>
Signed-off-by: Jonathan Cameron <Jonathan.Cameron@huawei.com>
2017-07-22 21:16:37 +01:00
Arushi Singhal 5e13b6f0e7 drivers: iio: chemical: replace comma with a semicolon
Replace a comma between expression statements by a semicolon. This
changes the semantics of the code, but given the current indentation
appears to be what is intended.
A simplified version of the Coccinelle semantic patch that performs this
transformation is as follows:

// <smpl>
@r@
expression e1,e2;
@@

 e1
-,
+;
 e2;
// </smpl>

Signed-off-by: Arushi Singhal <arushisinghal19971997@gmail.com>
Signed-off-by: Jonathan Cameron <jic23@kernel.org>
2017-03-30 19:13:23 +01:00
Sandhya Bankar d1fe85ec77 iio:chemical:atlas-ph-sensor: Fix use of 32 bit int to hold 16 bit big endian value
This will result in a random value being reported on big endian architectures.
(thanks to Lars-Peter Clausen for pointing out the effects of this bug)

Only effects a value printed to the log, but as this reports the settings of
the probe in question it may be of direct interest to users.

Also, fixes the following sparse endianness warnings:

drivers/iio/chemical/atlas-ph-sensor.c:215:9: warning: cast to restricted __be16
drivers/iio/chemical/atlas-ph-sensor.c:215:9: warning: cast to restricted __be16
drivers/iio/chemical/atlas-ph-sensor.c:215:9: warning: cast to restricted __be16
drivers/iio/chemical/atlas-ph-sensor.c:215:9: warning: cast to restricted __be16
drivers/iio/chemical/atlas-ph-sensor.c:215:9: warning: cast to restricted __be16
drivers/iio/chemical/atlas-ph-sensor.c:215:9: warning: cast to restricted __be16
drivers/iio/chemical/atlas-ph-sensor.c:215:9: warning: cast to restricted __be16
drivers/iio/chemical/atlas-ph-sensor.c:215:9: warning: cast to restricted __be16

Signed-off-by: Sandhya Bankar <bankarsandhya512@gmail.com>
Fixes: e8dd92bfbf ("iio: chemical: atlas-ph-sensor: add EC feature")
Cc: <Stable@vger.kernel.org>
Signed-off-by: Jonathan Cameron <jic23@kernel.org>
2016-10-23 22:18:27 +01:00
Greg Kroah-Hartman 552edf8d79 Second set of iio new device support, features and cleanups for the 4.9 cycle.
New device support
 * ad8801 dac
   - new driver supporting ad8801 and ad8803 DACs.
 * adc12138
   - new driver supporting TI adc12130/adc12132 and adc12138 ADCs.
 * ltc2485 adc
   - new driver
 * mxc6255
   - add support for the mxc6225 part name and fixup the ID check so it works.
 * vz89x VOC sensor
   - add support for the vz89te part which drops the voc_short channel and adds
     CRCs compared to other supported parts.
 
 New features
 * core
   - immutable triggers.  These effectively grant exclusive control over a
     trigger. The typical usecase is a device representing an analog part
     (perhaps a MUX) that needs to control the sampling of a downstream
     ADC.
   - resource managed trigger registration and triggered_buffer_init.
   - iio_push_event now protected against case of the event interface
     registration not having yet occured.  Only matters if an interrupt
     can occur during this window - might happen on shared interrupt lines.
   - helper to let a driver query if the trigger it is using is provided by
     itself (using the convention of both device and trigger having the same
     parent).
 * tools
   - iio-utils. Used channel modifier scaling in preference to generic scaling
     when both exist.
 * at91-adc
   - Add support for touchscreen switches closure time needed by some newer
     parts.
 * stx104
   - support the ADC channels on this ADC/DAC board. As these are the primary
     feature of the board also move the driver to the iio/adc directory.
 * sx9500
   - device tree bindings.
 
 Cleanups / Fixes
 * ad5755
   - fix an off-by-one on devnr limit check (introduced earlier this cycle)
 * ad7266
   - drop NULL check on devm_regulator_get_optional as it can't return NULL.
 * ak8974
   - avoid an unused functional warning due to rework in PM core code.
   - remove .owner field setting as done by i2c_core.
 * ina2xx
   - clear out a left over debug field from chip global data.
 * hid-sensors
   - avoid an unused functional warning due to rework in PM core code.
 * maxim-thermocouple
   - fix non static symbol warnings.
 * ms5611
   - fetch and enable regulators unconditionally when they aren't optional.
 * sca3000
   - whitespace cleanup.
 * st_sensors
   - fetch and enable regulators unconditionally rather than having them
     supported as optional regulators (missunderstanding on my part amongst
     others a while back)
   - followup to previous patch fixes error checking on the regulators.
   - mark symbols static where possible.
   - use the 'is it my trigger' help function.  This prevents the odd case
     of another device triggering from the st-sensors trigger whilst the
     st-sensors trigger is itself not using it but rather using say an hrtimer.
 * ti-ads1015
   - add missing of_node_put.
 * vz89x
   - rework to all support of new devices.
   - prevent reading of a corrupted buffer.
   - fixup a return value of 0/1 in a bool returning function.
 
 Address updates
 - Vlad Dogaru email address change.
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Merge tag 'iio-for-4.9b' of git://git.kernel.org/pub/scm/linux/kernel/git/jic23/iio into staging-next

Jonathan writes:

Second set of iio new device support, features and cleanups for the 4.9 cycle.

New device support
* ad8801 dac
  - new driver supporting ad8801 and ad8803 DACs.
* adc12138
  - new driver supporting TI adc12130/adc12132 and adc12138 ADCs.
* ltc2485 adc
  - new driver
* mxc6255
  - add support for the mxc6225 part name and fixup the ID check so it works.
* vz89x VOC sensor
  - add support for the vz89te part which drops the voc_short channel and adds
    CRCs compared to other supported parts.

New features
* core
  - immutable triggers.  These effectively grant exclusive control over a
    trigger. The typical usecase is a device representing an analog part
    (perhaps a MUX) that needs to control the sampling of a downstream
    ADC.
  - resource managed trigger registration and triggered_buffer_init.
  - iio_push_event now protected against case of the event interface
    registration not having yet occured.  Only matters if an interrupt
    can occur during this window - might happen on shared interrupt lines.
  - helper to let a driver query if the trigger it is using is provided by
    itself (using the convention of both device and trigger having the same
    parent).
* tools
  - iio-utils. Used channel modifier scaling in preference to generic scaling
    when both exist.
* at91-adc
  - Add support for touchscreen switches closure time needed by some newer
    parts.
* stx104
  - support the ADC channels on this ADC/DAC board. As these are the primary
    feature of the board also move the driver to the iio/adc directory.
* sx9500
  - device tree bindings.

Cleanups / Fixes
* ad5755
  - fix an off-by-one on devnr limit check (introduced earlier this cycle)
* ad7266
  - drop NULL check on devm_regulator_get_optional as it can't return NULL.
* ak8974
  - avoid an unused functional warning due to rework in PM core code.
  - remove .owner field setting as done by i2c_core.
* ina2xx
  - clear out a left over debug field from chip global data.
* hid-sensors
  - avoid an unused functional warning due to rework in PM core code.
* maxim-thermocouple
  - fix non static symbol warnings.
* ms5611
  - fetch and enable regulators unconditionally when they aren't optional.
* sca3000
  - whitespace cleanup.
* st_sensors
  - fetch and enable regulators unconditionally rather than having them
    supported as optional regulators (missunderstanding on my part amongst
    others a while back)
  - followup to previous patch fixes error checking on the regulators.
  - mark symbols static where possible.
  - use the 'is it my trigger' help function.  This prevents the odd case
    of another device triggering from the st-sensors trigger whilst the
    st-sensors trigger is itself not using it but rather using say an hrtimer.
* ti-ads1015
  - add missing of_node_put.
* vz89x
  - rework to all support of new devices.
  - prevent reading of a corrupted buffer.
  - fixup a return value of 0/1 in a bool returning function.

Address updates
- Vlad Dogaru email address change.
2016-09-14 20:42:03 +02:00
Greg Kroah-Hartman 9c2edd8b5b Merge 4.8-rc5 into staging-next
We want the staging fixes in here as well to handle merge issues.

Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2016-09-05 08:13:24 +02:00
kbuild test robot 2535cc7ae0 iio: chemical: vz89x: fix boolreturn.cocci warnings
drivers/iio/chemical/vz89x.c:119:9-10: WARNING: return of 0/1 in function 'vz89x_measurement_is_valid' with return type bool

 Return statements in functions returning bool should use
 true/false instead of 1/0.
Generated by: scripts/coccinelle/misc/boolreturn.cocci

CC: Matt Ranostay <mranostay@gmail.com>
Signed-off-by: Fengguang Wu <fengguang.wu@intel.com>
Signed-off-by: Jonathan Cameron <jic23@kernel.org>
2016-09-03 17:49:53 +01:00
Matt Ranostay 9d1894cd19 iio: chemical: vz89x: prevent corrupted buffer from being read
Signed-off-by: Matt Ranostay <mranostay@gmail.com>
Signed-off-by: Jonathan Cameron <jic23@kernel.org>
2016-08-29 18:00:46 +01:00
Matt Ranostay 0a735aa07f iio: chemical: vz89x: add support for VZ89TE part
Add support the VZ89TE variant which removes the voc_short channel,
and has CRC check for data transactions.

Signed-off-by: Matt Ranostay <mranostay@gmail.com>
Signed-off-by: Jonathan Cameron <jic23@kernel.org>
2016-08-29 18:00:06 +01:00
Matt Ranostay 8376882f16 iio: chemical: vz89x: abstract chip configuration
Abstract chip configuration data to allow supporting multiple variants
of the VZ89 chemical sensor line.

Signed-off-by: Matt Ranostay <mranostay@gmail.com>
Signed-off-by: Jonathan Cameron <jic23@kernel.org>
2016-08-29 17:46:52 +01:00
Colin Ian King ca64d4bc80 iio: chemical: atlas-ph-sensor: fix typo in val assignment
Fix an incorrect assignment due to a typo on a variable name. The
variable val2 should be assigned 100000 and not val.

Signed-off-by: Colin Ian King <colin.king@canonical.com>
Reviewed-By: Matt Ranostay <mranostay@gmail.com>
Signed-off-by: Jonathan Cameron <jic23@kernel.org>
2016-08-21 16:23:27 +01:00
Matt Ranostay ce08cc986e iio: chemical: atlas-ph-sensor: add ORP feature
Signed-off-by: Matt Ranostay <mranostay@gmail.com>
Signed-off-by: Jonathan Cameron <jic23@kernel.org>
2016-08-21 11:59:53 +01:00
Matt Ranostay d7c0e5ae70 iio: chemical: atlas-ph-sensor: switch to REGCACHE_NONE regmap tree
Since there are overlapping volatile regions between parts, and only
register that isn't volatile is the temperature compensation provided
from userspace.

Signed-off-by: Matt Ranostay <mranostay@gmail.com>
Signed-off-by: Jonathan Cameron <jic23@kernel.org>
2016-08-21 11:57:59 +01:00
Matt Ranostay b015b3e321 iio: chemical: atlas-ph-sensor: switch to iio_device_*_direct_mode helpers
Signed-off-by: Matt Ranostay <mranostay@gmail.com>
Signed-off-by: Jonathan Cameron <jic23@kernel.org>
2016-08-21 11:55:30 +01:00
Gregor Boirie bc2b7dab62 iio:core: timestamping clock selection support
Adds a new per-device sysfs attribute "current_timestamp_clock" to allow
userspace to select a particular POSIX clock for buffered samples and
events timestamping.

Following clocks, as listed in clock_gettime(2), are supported:
CLOCK_REALTIME, CLOCK_MONOTONIC, CLOCK_MONOTONIC_RAW,
CLOCK_REALTIME_COARSE, CLOCK_MONOTONIC_COARSE, CLOCK_BOOTTIME and
CLOCK_TAI.

Signed-off-by: Gregor Boirie <gregor.boirie@parrot.com>
Acked-by: Sanchayan Maity <maitysanchayan@gmail.com>
Signed-off-by: Jonathan Cameron <jic23@kernel.org>
2016-06-30 19:41:38 +01:00
Matt Ranostay e8dd92bfbf iio: chemical: atlas-ph-sensor: add EC feature
Signed-off-by: Matt Ranostay <mranostay@gmail.com>
Signed-off-by: Jonathan Cameron <jic23@kernel.org>
2016-05-29 20:03:23 +01:00
Matt Ranostay 7103b99b03 iio: chemical: atlas-ph-sensor: reorg driver to allow multiple chips
Signed-off-by: Matt Ranostay <mranostay@gmail.com>
Signed-off-by: Jonathan Cameron <jic23@kernel.org>
2016-05-29 20:03:16 +01:00
Matt Ranostay f8d9d3b434 iio: convert to common i2c_check_functionality() return value
Previously most drivers that used a i2c_check_functionality() check
condition required various error codes on failure. This patchset
converts to a standard of -EOPNOTSUPP

Signed-off-by: Matt Ranostay <mranostay@gmail.com>
Signed-off-by: Jonathan Cameron <jic23@kernel.org>
2016-02-27 17:17:43 +00:00
Matt Ranostay 98e55e93a0 iio: chemical: atlas-ph-sensor: use regmap_bulk_read
Replaced i2c_smbus_read_i2c_block_data() with regmap_bulk_read()
function call. This is to make the driver code more consistent.

Signed-off-by: Matt Ranostay <mranostay@gmail.com>
Signed-off-by: Jonathan Cameron <jic23@kernel.org>
2016-02-24 20:40:40 +00:00
Matt Ranostay 0d43b34688 iio: chemical: atlas-ph-sensor: switch regmap cache
switch from using REGCACHE_FLAT to REGCACHE_RBTREE so initial hw values
are read from device. This also allows some volatile ranges to be
dropped.

Note that REGCACHE_FLAT is intended only for very low lag cases so doesn't
do nice things like read initial values from the device.  Hence this change.

Signed-off-by: Matt Ranostay <mranostay@gmail.com>
Signed-off-by: Jonathan Cameron <jic23@kernel.org>
2016-02-19 18:57:13 +00:00
Arnd Bergmann 3b31b783ad iio: chemical: select IRQ_WORK for ATLAS ph sensor
The newly added atlas-ph-sensor driver uses irq_work_queue, which
may not always be enabled:

ERROR: "irq_work_queue" [drivers/iio/chemical/atlas-ph-sensor.ko] undefined!

This adds a 'select' statement to Kconfig to ensure it's there
when we need it.

Signed-off-by: Arnd Bergmann <arnd@arndb.de>
Fixes: 27dec00ecf ("iio: chemical: add Atlas pH-SM sensor support")
Reviewed-by: Matt Ranostay <mranostay@gmail.com>
Signed-off-by: Jonathan Cameron <jic23@kernel.org>
2016-02-06 18:36:58 +00:00
Matt Ranostay 27dec00ecf iio: chemical: add Atlas pH-SM sensor support
Add support for the Atlas Scientific pH-SM chemical sensor that can
detect pH levels of solutions in the range of 0-14.

Signed-off-by: Matt Ranostay <mranostay@gmail.com>
Signed-off-by: Jonathan Cameron <jic23@kernel.org>
2016-01-30 16:27:17 +00:00
Matt Ranostay 466df4d0c1 iio: chemical: add AMS iAQ-core support
Add support for AMS iAQ-core continuous and pulsed VOC sensors.

Signed-off-by: Matt Ranostay <mranostay@gmail.com>
Signed-off-by: Jonathan Cameron <jic23@kernel.org>
2015-12-12 15:07:38 +00:00
Matt Ranostay 93e87d73cc iio: chemical: vz89x: rework i2c transfer reading
Add an optimized i2c transfer reading function, and fallback
to racey smbus transfers if client->adapter doesn't support this.

Signed-off-by: Matt Ranostay <mranostay@gmail.com>
Signed-off-by: Jonathan Cameron <jic23@kernel.org>
2015-12-03 18:31:12 +00:00
Matt Ranostay bf23cee62d iio: chemical: vz89x hardware i2c workaround
Chipset sometime updates in the middle of a reading causing it
to reset the data pointer, and causing invalid reading of previous data.

We can check for this invalid state by reading MSB of the resistance
reading that is always zero, and by also confirming the VOC_short isn't
zero.

Signed-off-by: Matt Ranostay <mranostay@gmail.com>
Signed-off-by: Jonathan Cameron <jic23@kernel.org>
2015-09-30 18:20:53 +01:00
Matt Ranostay cd8d97774f iio: chemical: add SGX VZ89x VOC sensor support
Add support for VZ89X sensors VOC and CO2 reporting channels in
percentage which can be converted to part per million.

Signed-off-by: Matt Ranostay <mranostay@gmail.com>
Signed-off-by: Jonathan Cameron <jic23@kernel.org>
2015-09-23 20:23:26 +01:00