2059 lines
54 KiB
C
2059 lines
54 KiB
C
// SPDX-License-Identifier: GPL-2.0
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/*
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* Driver for STMicroelectronics STM32F7 I2C controller
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*
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* This I2C controller is described in the STM32F75xxx and STM32F74xxx Soc
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* reference manual.
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* Please see below a link to the documentation:
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* http://www.st.com/resource/en/reference_manual/dm00124865.pdf
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*
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* Copyright (C) M'boumba Cedric Madianga 2017
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* Copyright (C) STMicroelectronics 2017
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* Author: M'boumba Cedric Madianga <cedric.madianga@gmail.com>
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*
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* This driver is based on i2c-stm32f4.c
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*
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*/
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#include <linux/clk.h>
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#include <linux/delay.h>
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#include <linux/err.h>
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#include <linux/i2c.h>
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#include <linux/interrupt.h>
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#include <linux/io.h>
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#include <linux/iopoll.h>
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#include <linux/mfd/syscon.h>
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#include <linux/module.h>
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#include <linux/of.h>
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#include <linux/of_address.h>
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#include <linux/of_irq.h>
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#include <linux/of_platform.h>
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#include <linux/platform_device.h>
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#include <linux/pinctrl/consumer.h>
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#include <linux/pm_runtime.h>
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#include <linux/regmap.h>
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#include <linux/reset.h>
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#include <linux/slab.h>
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#include "i2c-stm32.h"
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/* STM32F7 I2C registers */
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#define STM32F7_I2C_CR1 0x00
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#define STM32F7_I2C_CR2 0x04
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#define STM32F7_I2C_OAR1 0x08
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#define STM32F7_I2C_OAR2 0x0C
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#define STM32F7_I2C_PECR 0x20
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#define STM32F7_I2C_TIMINGR 0x10
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#define STM32F7_I2C_ISR 0x18
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#define STM32F7_I2C_ICR 0x1C
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#define STM32F7_I2C_RXDR 0x24
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#define STM32F7_I2C_TXDR 0x28
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/* STM32F7 I2C control 1 */
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#define STM32F7_I2C_CR1_PECEN BIT(23)
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#define STM32F7_I2C_CR1_SBC BIT(16)
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#define STM32F7_I2C_CR1_RXDMAEN BIT(15)
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#define STM32F7_I2C_CR1_TXDMAEN BIT(14)
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#define STM32F7_I2C_CR1_ANFOFF BIT(12)
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#define STM32F7_I2C_CR1_ERRIE BIT(7)
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#define STM32F7_I2C_CR1_TCIE BIT(6)
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#define STM32F7_I2C_CR1_STOPIE BIT(5)
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#define STM32F7_I2C_CR1_NACKIE BIT(4)
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#define STM32F7_I2C_CR1_ADDRIE BIT(3)
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#define STM32F7_I2C_CR1_RXIE BIT(2)
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#define STM32F7_I2C_CR1_TXIE BIT(1)
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#define STM32F7_I2C_CR1_PE BIT(0)
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#define STM32F7_I2C_ALL_IRQ_MASK (STM32F7_I2C_CR1_ERRIE \
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| STM32F7_I2C_CR1_TCIE \
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| STM32F7_I2C_CR1_STOPIE \
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| STM32F7_I2C_CR1_NACKIE \
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| STM32F7_I2C_CR1_RXIE \
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| STM32F7_I2C_CR1_TXIE)
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#define STM32F7_I2C_XFER_IRQ_MASK (STM32F7_I2C_CR1_TCIE \
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| STM32F7_I2C_CR1_STOPIE \
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| STM32F7_I2C_CR1_NACKIE \
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| STM32F7_I2C_CR1_RXIE \
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| STM32F7_I2C_CR1_TXIE)
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/* STM32F7 I2C control 2 */
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#define STM32F7_I2C_CR2_PECBYTE BIT(26)
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#define STM32F7_I2C_CR2_RELOAD BIT(24)
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#define STM32F7_I2C_CR2_NBYTES_MASK GENMASK(23, 16)
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#define STM32F7_I2C_CR2_NBYTES(n) (((n) & 0xff) << 16)
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#define STM32F7_I2C_CR2_NACK BIT(15)
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#define STM32F7_I2C_CR2_STOP BIT(14)
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#define STM32F7_I2C_CR2_START BIT(13)
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#define STM32F7_I2C_CR2_HEAD10R BIT(12)
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#define STM32F7_I2C_CR2_ADD10 BIT(11)
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#define STM32F7_I2C_CR2_RD_WRN BIT(10)
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#define STM32F7_I2C_CR2_SADD10_MASK GENMASK(9, 0)
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#define STM32F7_I2C_CR2_SADD10(n) (((n) & \
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STM32F7_I2C_CR2_SADD10_MASK))
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#define STM32F7_I2C_CR2_SADD7_MASK GENMASK(7, 1)
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#define STM32F7_I2C_CR2_SADD7(n) (((n) & 0x7f) << 1)
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/* STM32F7 I2C Own Address 1 */
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#define STM32F7_I2C_OAR1_OA1EN BIT(15)
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#define STM32F7_I2C_OAR1_OA1MODE BIT(10)
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#define STM32F7_I2C_OAR1_OA1_10_MASK GENMASK(9, 0)
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#define STM32F7_I2C_OAR1_OA1_10(n) (((n) & \
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STM32F7_I2C_OAR1_OA1_10_MASK))
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#define STM32F7_I2C_OAR1_OA1_7_MASK GENMASK(7, 1)
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#define STM32F7_I2C_OAR1_OA1_7(n) (((n) & 0x7f) << 1)
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#define STM32F7_I2C_OAR1_MASK (STM32F7_I2C_OAR1_OA1_7_MASK \
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| STM32F7_I2C_OAR1_OA1_10_MASK \
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| STM32F7_I2C_OAR1_OA1EN \
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| STM32F7_I2C_OAR1_OA1MODE)
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/* STM32F7 I2C Own Address 2 */
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#define STM32F7_I2C_OAR2_OA2EN BIT(15)
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#define STM32F7_I2C_OAR2_OA2MSK_MASK GENMASK(10, 8)
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#define STM32F7_I2C_OAR2_OA2MSK(n) (((n) & 0x7) << 8)
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#define STM32F7_I2C_OAR2_OA2_7_MASK GENMASK(7, 1)
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#define STM32F7_I2C_OAR2_OA2_7(n) (((n) & 0x7f) << 1)
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#define STM32F7_I2C_OAR2_MASK (STM32F7_I2C_OAR2_OA2MSK_MASK \
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| STM32F7_I2C_OAR2_OA2_7_MASK \
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| STM32F7_I2C_OAR2_OA2EN)
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/* STM32F7 I2C Interrupt Status */
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#define STM32F7_I2C_ISR_ADDCODE_MASK GENMASK(23, 17)
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#define STM32F7_I2C_ISR_ADDCODE_GET(n) \
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(((n) & STM32F7_I2C_ISR_ADDCODE_MASK) >> 17)
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#define STM32F7_I2C_ISR_DIR BIT(16)
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#define STM32F7_I2C_ISR_BUSY BIT(15)
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#define STM32F7_I2C_ISR_PECERR BIT(11)
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#define STM32F7_I2C_ISR_ARLO BIT(9)
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#define STM32F7_I2C_ISR_BERR BIT(8)
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#define STM32F7_I2C_ISR_TCR BIT(7)
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#define STM32F7_I2C_ISR_TC BIT(6)
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#define STM32F7_I2C_ISR_STOPF BIT(5)
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#define STM32F7_I2C_ISR_NACKF BIT(4)
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#define STM32F7_I2C_ISR_ADDR BIT(3)
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#define STM32F7_I2C_ISR_RXNE BIT(2)
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#define STM32F7_I2C_ISR_TXIS BIT(1)
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#define STM32F7_I2C_ISR_TXE BIT(0)
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/* STM32F7 I2C Interrupt Clear */
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#define STM32F7_I2C_ICR_PECCF BIT(11)
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#define STM32F7_I2C_ICR_ARLOCF BIT(9)
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#define STM32F7_I2C_ICR_BERRCF BIT(8)
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#define STM32F7_I2C_ICR_STOPCF BIT(5)
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#define STM32F7_I2C_ICR_NACKCF BIT(4)
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#define STM32F7_I2C_ICR_ADDRCF BIT(3)
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/* STM32F7 I2C Timing */
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#define STM32F7_I2C_TIMINGR_PRESC(n) (((n) & 0xf) << 28)
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#define STM32F7_I2C_TIMINGR_SCLDEL(n) (((n) & 0xf) << 20)
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#define STM32F7_I2C_TIMINGR_SDADEL(n) (((n) & 0xf) << 16)
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#define STM32F7_I2C_TIMINGR_SCLH(n) (((n) & 0xff) << 8)
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#define STM32F7_I2C_TIMINGR_SCLL(n) ((n) & 0xff)
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#define STM32F7_I2C_MAX_LEN 0xff
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#define STM32F7_I2C_DMA_LEN_MIN 0x16
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#define STM32F7_I2C_MAX_SLAVE 0x2
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#define STM32F7_I2C_DNF_DEFAULT 0
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#define STM32F7_I2C_DNF_MAX 16
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#define STM32F7_I2C_ANALOG_FILTER_ENABLE 1
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#define STM32F7_I2C_ANALOG_FILTER_DELAY_MIN 50 /* ns */
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#define STM32F7_I2C_ANALOG_FILTER_DELAY_MAX 260 /* ns */
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#define STM32F7_I2C_RISE_TIME_DEFAULT 25 /* ns */
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#define STM32F7_I2C_FALL_TIME_DEFAULT 10 /* ns */
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#define STM32F7_PRESC_MAX BIT(4)
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#define STM32F7_SCLDEL_MAX BIT(4)
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#define STM32F7_SDADEL_MAX BIT(4)
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#define STM32F7_SCLH_MAX BIT(8)
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#define STM32F7_SCLL_MAX BIT(8)
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#define STM32F7_AUTOSUSPEND_DELAY (HZ / 100)
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/**
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* struct stm32f7_i2c_spec - private i2c specification timing
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* @rate: I2C bus speed (Hz)
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* @rate_min: 80% of I2C bus speed (Hz)
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* @rate_max: 100% of I2C bus speed (Hz)
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* @fall_max: Max fall time of both SDA and SCL signals (ns)
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* @rise_max: Max rise time of both SDA and SCL signals (ns)
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* @hddat_min: Min data hold time (ns)
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* @vddat_max: Max data valid time (ns)
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* @sudat_min: Min data setup time (ns)
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* @l_min: Min low period of the SCL clock (ns)
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* @h_min: Min high period of the SCL clock (ns)
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*/
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struct stm32f7_i2c_spec {
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u32 rate;
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u32 rate_min;
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u32 rate_max;
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u32 fall_max;
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u32 rise_max;
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u32 hddat_min;
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u32 vddat_max;
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u32 sudat_min;
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u32 l_min;
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u32 h_min;
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};
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/**
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* struct stm32f7_i2c_setup - private I2C timing setup parameters
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* @speed: I2C speed mode (standard, Fast Plus)
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* @speed_freq: I2C speed frequency (Hz)
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* @clock_src: I2C clock source frequency (Hz)
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* @rise_time: Rise time (ns)
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* @fall_time: Fall time (ns)
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* @dnf: Digital filter coefficient (0-16)
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* @analog_filter: Analog filter delay (On/Off)
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*/
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struct stm32f7_i2c_setup {
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enum stm32_i2c_speed speed;
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u32 speed_freq;
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u32 clock_src;
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u32 rise_time;
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u32 fall_time;
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u8 dnf;
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bool analog_filter;
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};
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/**
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* struct stm32f7_i2c_timings - private I2C output parameters
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* @node: List entry
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* @presc: Prescaler value
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* @scldel: Data setup time
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* @sdadel: Data hold time
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* @sclh: SCL high period (master mode)
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* @scll: SCL low period (master mode)
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*/
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struct stm32f7_i2c_timings {
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struct list_head node;
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u8 presc;
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u8 scldel;
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u8 sdadel;
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u8 sclh;
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u8 scll;
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};
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/**
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* struct stm32f7_i2c_msg - client specific data
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* @addr: 8-bit or 10-bit slave addr, including r/w bit
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* @count: number of bytes to be transferred
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* @buf: data buffer
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* @result: result of the transfer
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* @stop: last I2C msg to be sent, i.e. STOP to be generated
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* @smbus: boolean to know if the I2C IP is used in SMBus mode
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* @size: type of SMBus protocol
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* @read_write: direction of SMBus protocol
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* SMBus block read and SMBus block write - block read process call protocols
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* @smbus_buf: buffer to be used for SMBus protocol transfer. It will
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* contain a maximum of 32 bytes of data + byte command + byte count + PEC
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* This buffer has to be 32-bit aligned to be compliant with memory address
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* register in DMA mode.
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*/
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struct stm32f7_i2c_msg {
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u16 addr;
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u32 count;
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u8 *buf;
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int result;
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bool stop;
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bool smbus;
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int size;
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char read_write;
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u8 smbus_buf[I2C_SMBUS_BLOCK_MAX + 3] __aligned(4);
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};
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/**
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* struct stm32f7_i2c_dev - private data of the controller
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* @adap: I2C adapter for this controller
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* @dev: device for this controller
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* @base: virtual memory area
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* @complete: completion of I2C message
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* @clk: hw i2c clock
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* @speed: I2C clock frequency of the controller. Standard, Fast or Fast+
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* @msg: Pointer to data to be written
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* @msg_num: number of I2C messages to be executed
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* @msg_id: message identifiant
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* @f7_msg: customized i2c msg for driver usage
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* @setup: I2C timing input setup
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* @timing: I2C computed timings
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* @slave: list of slave devices registered on the I2C bus
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* @slave_running: slave device currently used
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* @slave_dir: transfer direction for the current slave device
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* @master_mode: boolean to know in which mode the I2C is running (master or
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* slave)
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* @dma: dma data
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* @use_dma: boolean to know if dma is used in the current transfer
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* @regmap: holds SYSCFG phandle for Fast Mode Plus bits
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*/
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struct stm32f7_i2c_dev {
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struct i2c_adapter adap;
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struct device *dev;
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void __iomem *base;
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struct completion complete;
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struct clk *clk;
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int speed;
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struct i2c_msg *msg;
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unsigned int msg_num;
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unsigned int msg_id;
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struct stm32f7_i2c_msg f7_msg;
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struct stm32f7_i2c_setup setup;
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struct stm32f7_i2c_timings timing;
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struct i2c_client *slave[STM32F7_I2C_MAX_SLAVE];
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struct i2c_client *slave_running;
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u32 slave_dir;
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bool master_mode;
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struct stm32_i2c_dma *dma;
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bool use_dma;
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struct regmap *regmap;
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};
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/**
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* All these values are coming from I2C Specification, Version 6.0, 4th of
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* April 2014.
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*
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* Table10. Characteristics of the SDA and SCL bus lines for Standard, Fast,
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* and Fast-mode Plus I2C-bus devices
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*/
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static struct stm32f7_i2c_spec i2c_specs[] = {
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[STM32_I2C_SPEED_STANDARD] = {
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.rate = 100000,
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.rate_min = 80000,
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.rate_max = 100000,
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.fall_max = 300,
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.rise_max = 1000,
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.hddat_min = 0,
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.vddat_max = 3450,
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.sudat_min = 250,
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.l_min = 4700,
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.h_min = 4000,
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},
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[STM32_I2C_SPEED_FAST] = {
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.rate = 400000,
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.rate_min = 320000,
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.rate_max = 400000,
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.fall_max = 300,
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.rise_max = 300,
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.hddat_min = 0,
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.vddat_max = 900,
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.sudat_min = 100,
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.l_min = 1300,
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.h_min = 600,
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},
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[STM32_I2C_SPEED_FAST_PLUS] = {
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.rate = 1000000,
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.rate_min = 800000,
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.rate_max = 1000000,
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.fall_max = 100,
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.rise_max = 120,
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.hddat_min = 0,
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.vddat_max = 450,
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.sudat_min = 50,
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.l_min = 500,
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.h_min = 260,
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},
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};
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static const struct stm32f7_i2c_setup stm32f7_setup = {
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.rise_time = STM32F7_I2C_RISE_TIME_DEFAULT,
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.fall_time = STM32F7_I2C_FALL_TIME_DEFAULT,
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.dnf = STM32F7_I2C_DNF_DEFAULT,
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.analog_filter = STM32F7_I2C_ANALOG_FILTER_ENABLE,
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};
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static inline void stm32f7_i2c_set_bits(void __iomem *reg, u32 mask)
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{
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writel_relaxed(readl_relaxed(reg) | mask, reg);
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}
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static inline void stm32f7_i2c_clr_bits(void __iomem *reg, u32 mask)
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{
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writel_relaxed(readl_relaxed(reg) & ~mask, reg);
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}
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static void stm32f7_i2c_disable_irq(struct stm32f7_i2c_dev *i2c_dev, u32 mask)
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{
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stm32f7_i2c_clr_bits(i2c_dev->base + STM32F7_I2C_CR1, mask);
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}
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static int stm32f7_i2c_compute_timing(struct stm32f7_i2c_dev *i2c_dev,
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struct stm32f7_i2c_setup *setup,
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struct stm32f7_i2c_timings *output)
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{
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u32 p_prev = STM32F7_PRESC_MAX;
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u32 i2cclk = DIV_ROUND_CLOSEST(NSEC_PER_SEC,
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setup->clock_src);
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u32 i2cbus = DIV_ROUND_CLOSEST(NSEC_PER_SEC,
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setup->speed_freq);
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u32 clk_error_prev = i2cbus;
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u32 tsync;
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u32 af_delay_min, af_delay_max;
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u32 dnf_delay;
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u32 clk_min, clk_max;
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int sdadel_min, sdadel_max;
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int scldel_min;
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struct stm32f7_i2c_timings *v, *_v, *s;
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struct list_head solutions;
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u16 p, l, a, h;
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int ret = 0;
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|
|
if (setup->speed >= STM32_I2C_SPEED_END) {
|
|
dev_err(i2c_dev->dev, "speed out of bound {%d/%d}\n",
|
|
setup->speed, STM32_I2C_SPEED_END - 1);
|
|
return -EINVAL;
|
|
}
|
|
|
|
if ((setup->rise_time > i2c_specs[setup->speed].rise_max) ||
|
|
(setup->fall_time > i2c_specs[setup->speed].fall_max)) {
|
|
dev_err(i2c_dev->dev,
|
|
"timings out of bound Rise{%d>%d}/Fall{%d>%d}\n",
|
|
setup->rise_time, i2c_specs[setup->speed].rise_max,
|
|
setup->fall_time, i2c_specs[setup->speed].fall_max);
|
|
return -EINVAL;
|
|
}
|
|
|
|
if (setup->dnf > STM32F7_I2C_DNF_MAX) {
|
|
dev_err(i2c_dev->dev,
|
|
"DNF out of bound %d/%d\n",
|
|
setup->dnf, STM32F7_I2C_DNF_MAX);
|
|
return -EINVAL;
|
|
}
|
|
|
|
if (setup->speed_freq > i2c_specs[setup->speed].rate) {
|
|
dev_err(i2c_dev->dev, "ERROR: Freq {%d/%d}\n",
|
|
setup->speed_freq, i2c_specs[setup->speed].rate);
|
|
return -EINVAL;
|
|
}
|
|
|
|
/* Analog and Digital Filters */
|
|
af_delay_min =
|
|
(setup->analog_filter ?
|
|
STM32F7_I2C_ANALOG_FILTER_DELAY_MIN : 0);
|
|
af_delay_max =
|
|
(setup->analog_filter ?
|
|
STM32F7_I2C_ANALOG_FILTER_DELAY_MAX : 0);
|
|
dnf_delay = setup->dnf * i2cclk;
|
|
|
|
sdadel_min = i2c_specs[setup->speed].hddat_min + setup->fall_time -
|
|
af_delay_min - (setup->dnf + 3) * i2cclk;
|
|
|
|
sdadel_max = i2c_specs[setup->speed].vddat_max - setup->rise_time -
|
|
af_delay_max - (setup->dnf + 4) * i2cclk;
|
|
|
|
scldel_min = setup->rise_time + i2c_specs[setup->speed].sudat_min;
|
|
|
|
if (sdadel_min < 0)
|
|
sdadel_min = 0;
|
|
if (sdadel_max < 0)
|
|
sdadel_max = 0;
|
|
|
|
dev_dbg(i2c_dev->dev, "SDADEL(min/max): %i/%i, SCLDEL(Min): %i\n",
|
|
sdadel_min, sdadel_max, scldel_min);
|
|
|
|
INIT_LIST_HEAD(&solutions);
|
|
/* Compute possible values for PRESC, SCLDEL and SDADEL */
|
|
for (p = 0; p < STM32F7_PRESC_MAX; p++) {
|
|
for (l = 0; l < STM32F7_SCLDEL_MAX; l++) {
|
|
u32 scldel = (l + 1) * (p + 1) * i2cclk;
|
|
|
|
if (scldel < scldel_min)
|
|
continue;
|
|
|
|
for (a = 0; a < STM32F7_SDADEL_MAX; a++) {
|
|
u32 sdadel = (a * (p + 1) + 1) * i2cclk;
|
|
|
|
if (((sdadel >= sdadel_min) &&
|
|
(sdadel <= sdadel_max)) &&
|
|
(p != p_prev)) {
|
|
v = kmalloc(sizeof(*v), GFP_KERNEL);
|
|
if (!v) {
|
|
ret = -ENOMEM;
|
|
goto exit;
|
|
}
|
|
|
|
v->presc = p;
|
|
v->scldel = l;
|
|
v->sdadel = a;
|
|
p_prev = p;
|
|
|
|
list_add_tail(&v->node,
|
|
&solutions);
|
|
break;
|
|
}
|
|
}
|
|
|
|
if (p_prev == p)
|
|
break;
|
|
}
|
|
}
|
|
|
|
if (list_empty(&solutions)) {
|
|
dev_err(i2c_dev->dev, "no Prescaler solution\n");
|
|
ret = -EPERM;
|
|
goto exit;
|
|
}
|
|
|
|
tsync = af_delay_min + dnf_delay + (2 * i2cclk);
|
|
s = NULL;
|
|
clk_max = NSEC_PER_SEC / i2c_specs[setup->speed].rate_min;
|
|
clk_min = NSEC_PER_SEC / i2c_specs[setup->speed].rate_max;
|
|
|
|
/*
|
|
* Among Prescaler possibilities discovered above figures out SCL Low
|
|
* and High Period. Provided:
|
|
* - SCL Low Period has to be higher than SCL Clock Low Period
|
|
* defined by I2C Specification. I2C Clock has to be lower than
|
|
* (SCL Low Period - Analog/Digital filters) / 4.
|
|
* - SCL High Period has to be lower than SCL Clock High Period
|
|
* defined by I2C Specification
|
|
* - I2C Clock has to be lower than SCL High Period
|
|
*/
|
|
list_for_each_entry(v, &solutions, node) {
|
|
u32 prescaler = (v->presc + 1) * i2cclk;
|
|
|
|
for (l = 0; l < STM32F7_SCLL_MAX; l++) {
|
|
u32 tscl_l = (l + 1) * prescaler + tsync;
|
|
|
|
if ((tscl_l < i2c_specs[setup->speed].l_min) ||
|
|
(i2cclk >=
|
|
((tscl_l - af_delay_min - dnf_delay) / 4))) {
|
|
continue;
|
|
}
|
|
|
|
for (h = 0; h < STM32F7_SCLH_MAX; h++) {
|
|
u32 tscl_h = (h + 1) * prescaler + tsync;
|
|
u32 tscl = tscl_l + tscl_h +
|
|
setup->rise_time + setup->fall_time;
|
|
|
|
if ((tscl >= clk_min) && (tscl <= clk_max) &&
|
|
(tscl_h >= i2c_specs[setup->speed].h_min) &&
|
|
(i2cclk < tscl_h)) {
|
|
int clk_error = tscl - i2cbus;
|
|
|
|
if (clk_error < 0)
|
|
clk_error = -clk_error;
|
|
|
|
if (clk_error < clk_error_prev) {
|
|
clk_error_prev = clk_error;
|
|
v->scll = l;
|
|
v->sclh = h;
|
|
s = v;
|
|
}
|
|
}
|
|
}
|
|
}
|
|
}
|
|
|
|
if (!s) {
|
|
dev_err(i2c_dev->dev, "no solution at all\n");
|
|
ret = -EPERM;
|
|
goto exit;
|
|
}
|
|
|
|
output->presc = s->presc;
|
|
output->scldel = s->scldel;
|
|
output->sdadel = s->sdadel;
|
|
output->scll = s->scll;
|
|
output->sclh = s->sclh;
|
|
|
|
dev_dbg(i2c_dev->dev,
|
|
"Presc: %i, scldel: %i, sdadel: %i, scll: %i, sclh: %i\n",
|
|
output->presc,
|
|
output->scldel, output->sdadel,
|
|
output->scll, output->sclh);
|
|
|
|
exit:
|
|
/* Release list and memory */
|
|
list_for_each_entry_safe(v, _v, &solutions, node) {
|
|
list_del(&v->node);
|
|
kfree(v);
|
|
}
|
|
|
|
return ret;
|
|
}
|
|
|
|
static int stm32f7_i2c_setup_timing(struct stm32f7_i2c_dev *i2c_dev,
|
|
struct stm32f7_i2c_setup *setup)
|
|
{
|
|
int ret = 0;
|
|
|
|
setup->speed = i2c_dev->speed;
|
|
setup->speed_freq = i2c_specs[setup->speed].rate;
|
|
setup->clock_src = clk_get_rate(i2c_dev->clk);
|
|
|
|
if (!setup->clock_src) {
|
|
dev_err(i2c_dev->dev, "clock rate is 0\n");
|
|
return -EINVAL;
|
|
}
|
|
|
|
do {
|
|
ret = stm32f7_i2c_compute_timing(i2c_dev, setup,
|
|
&i2c_dev->timing);
|
|
if (ret) {
|
|
dev_err(i2c_dev->dev,
|
|
"failed to compute I2C timings.\n");
|
|
if (i2c_dev->speed > STM32_I2C_SPEED_STANDARD) {
|
|
i2c_dev->speed--;
|
|
setup->speed = i2c_dev->speed;
|
|
setup->speed_freq =
|
|
i2c_specs[setup->speed].rate;
|
|
dev_warn(i2c_dev->dev,
|
|
"downgrade I2C Speed Freq to (%i)\n",
|
|
i2c_specs[setup->speed].rate);
|
|
} else {
|
|
break;
|
|
}
|
|
}
|
|
} while (ret);
|
|
|
|
if (ret) {
|
|
dev_err(i2c_dev->dev, "Impossible to compute I2C timings.\n");
|
|
return ret;
|
|
}
|
|
|
|
dev_dbg(i2c_dev->dev, "I2C Speed(%i), Freq(%i), Clk Source(%i)\n",
|
|
setup->speed, setup->speed_freq, setup->clock_src);
|
|
dev_dbg(i2c_dev->dev, "I2C Rise(%i) and Fall(%i) Time\n",
|
|
setup->rise_time, setup->fall_time);
|
|
dev_dbg(i2c_dev->dev, "I2C Analog Filter(%s), DNF(%i)\n",
|
|
(setup->analog_filter ? "On" : "Off"), setup->dnf);
|
|
|
|
return 0;
|
|
}
|
|
|
|
static void stm32f7_i2c_disable_dma_req(struct stm32f7_i2c_dev *i2c_dev)
|
|
{
|
|
void __iomem *base = i2c_dev->base;
|
|
u32 mask = STM32F7_I2C_CR1_RXDMAEN | STM32F7_I2C_CR1_TXDMAEN;
|
|
|
|
stm32f7_i2c_clr_bits(base + STM32F7_I2C_CR1, mask);
|
|
}
|
|
|
|
static void stm32f7_i2c_dma_callback(void *arg)
|
|
{
|
|
struct stm32f7_i2c_dev *i2c_dev = (struct stm32f7_i2c_dev *)arg;
|
|
struct stm32_i2c_dma *dma = i2c_dev->dma;
|
|
struct device *dev = dma->chan_using->device->dev;
|
|
|
|
stm32f7_i2c_disable_dma_req(i2c_dev);
|
|
dma_unmap_single(dev, dma->dma_buf, dma->dma_len, dma->dma_data_dir);
|
|
complete(&dma->dma_complete);
|
|
}
|
|
|
|
static void stm32f7_i2c_hw_config(struct stm32f7_i2c_dev *i2c_dev)
|
|
{
|
|
struct stm32f7_i2c_timings *t = &i2c_dev->timing;
|
|
u32 timing = 0;
|
|
|
|
/* Timing settings */
|
|
timing |= STM32F7_I2C_TIMINGR_PRESC(t->presc);
|
|
timing |= STM32F7_I2C_TIMINGR_SCLDEL(t->scldel);
|
|
timing |= STM32F7_I2C_TIMINGR_SDADEL(t->sdadel);
|
|
timing |= STM32F7_I2C_TIMINGR_SCLH(t->sclh);
|
|
timing |= STM32F7_I2C_TIMINGR_SCLL(t->scll);
|
|
writel_relaxed(timing, i2c_dev->base + STM32F7_I2C_TIMINGR);
|
|
|
|
/* Enable I2C */
|
|
if (i2c_dev->setup.analog_filter)
|
|
stm32f7_i2c_clr_bits(i2c_dev->base + STM32F7_I2C_CR1,
|
|
STM32F7_I2C_CR1_ANFOFF);
|
|
else
|
|
stm32f7_i2c_set_bits(i2c_dev->base + STM32F7_I2C_CR1,
|
|
STM32F7_I2C_CR1_ANFOFF);
|
|
stm32f7_i2c_set_bits(i2c_dev->base + STM32F7_I2C_CR1,
|
|
STM32F7_I2C_CR1_PE);
|
|
}
|
|
|
|
static void stm32f7_i2c_write_tx_data(struct stm32f7_i2c_dev *i2c_dev)
|
|
{
|
|
struct stm32f7_i2c_msg *f7_msg = &i2c_dev->f7_msg;
|
|
void __iomem *base = i2c_dev->base;
|
|
|
|
if (f7_msg->count) {
|
|
writeb_relaxed(*f7_msg->buf++, base + STM32F7_I2C_TXDR);
|
|
f7_msg->count--;
|
|
}
|
|
}
|
|
|
|
static void stm32f7_i2c_read_rx_data(struct stm32f7_i2c_dev *i2c_dev)
|
|
{
|
|
struct stm32f7_i2c_msg *f7_msg = &i2c_dev->f7_msg;
|
|
void __iomem *base = i2c_dev->base;
|
|
|
|
if (f7_msg->count) {
|
|
*f7_msg->buf++ = readb_relaxed(base + STM32F7_I2C_RXDR);
|
|
f7_msg->count--;
|
|
} else {
|
|
/* Flush RX buffer has no data is expected */
|
|
readb_relaxed(base + STM32F7_I2C_RXDR);
|
|
}
|
|
}
|
|
|
|
static void stm32f7_i2c_reload(struct stm32f7_i2c_dev *i2c_dev)
|
|
{
|
|
struct stm32f7_i2c_msg *f7_msg = &i2c_dev->f7_msg;
|
|
u32 cr2;
|
|
|
|
if (i2c_dev->use_dma)
|
|
f7_msg->count -= STM32F7_I2C_MAX_LEN;
|
|
|
|
cr2 = readl_relaxed(i2c_dev->base + STM32F7_I2C_CR2);
|
|
|
|
cr2 &= ~STM32F7_I2C_CR2_NBYTES_MASK;
|
|
if (f7_msg->count > STM32F7_I2C_MAX_LEN) {
|
|
cr2 |= STM32F7_I2C_CR2_NBYTES(STM32F7_I2C_MAX_LEN);
|
|
} else {
|
|
cr2 &= ~STM32F7_I2C_CR2_RELOAD;
|
|
cr2 |= STM32F7_I2C_CR2_NBYTES(f7_msg->count);
|
|
}
|
|
|
|
writel_relaxed(cr2, i2c_dev->base + STM32F7_I2C_CR2);
|
|
}
|
|
|
|
static void stm32f7_i2c_smbus_reload(struct stm32f7_i2c_dev *i2c_dev)
|
|
{
|
|
struct stm32f7_i2c_msg *f7_msg = &i2c_dev->f7_msg;
|
|
u32 cr2;
|
|
u8 *val;
|
|
|
|
/*
|
|
* For I2C_SMBUS_BLOCK_DATA && I2C_SMBUS_BLOCK_PROC_CALL, the first
|
|
* data received inform us how many data will follow.
|
|
*/
|
|
stm32f7_i2c_read_rx_data(i2c_dev);
|
|
|
|
/*
|
|
* Update NBYTES with the value read to continue the transfer
|
|
*/
|
|
val = f7_msg->buf - sizeof(u8);
|
|
f7_msg->count = *val;
|
|
cr2 = readl_relaxed(i2c_dev->base + STM32F7_I2C_CR2);
|
|
cr2 &= ~(STM32F7_I2C_CR2_NBYTES_MASK | STM32F7_I2C_CR2_RELOAD);
|
|
cr2 |= STM32F7_I2C_CR2_NBYTES(f7_msg->count);
|
|
writel_relaxed(cr2, i2c_dev->base + STM32F7_I2C_CR2);
|
|
}
|
|
|
|
static int stm32f7_i2c_release_bus(struct i2c_adapter *i2c_adap)
|
|
{
|
|
struct stm32f7_i2c_dev *i2c_dev = i2c_get_adapdata(i2c_adap);
|
|
|
|
dev_info(i2c_dev->dev, "Trying to recover bus\n");
|
|
|
|
stm32f7_i2c_clr_bits(i2c_dev->base + STM32F7_I2C_CR1,
|
|
STM32F7_I2C_CR1_PE);
|
|
|
|
stm32f7_i2c_hw_config(i2c_dev);
|
|
|
|
return 0;
|
|
}
|
|
|
|
static int stm32f7_i2c_wait_free_bus(struct stm32f7_i2c_dev *i2c_dev)
|
|
{
|
|
u32 status;
|
|
int ret;
|
|
|
|
ret = readl_relaxed_poll_timeout(i2c_dev->base + STM32F7_I2C_ISR,
|
|
status,
|
|
!(status & STM32F7_I2C_ISR_BUSY),
|
|
10, 1000);
|
|
if (!ret)
|
|
return 0;
|
|
|
|
dev_info(i2c_dev->dev, "bus busy\n");
|
|
|
|
ret = stm32f7_i2c_release_bus(&i2c_dev->adap);
|
|
if (ret) {
|
|
dev_err(i2c_dev->dev, "Failed to recover the bus (%d)\n", ret);
|
|
return ret;
|
|
}
|
|
|
|
return -EBUSY;
|
|
}
|
|
|
|
static void stm32f7_i2c_xfer_msg(struct stm32f7_i2c_dev *i2c_dev,
|
|
struct i2c_msg *msg)
|
|
{
|
|
struct stm32f7_i2c_msg *f7_msg = &i2c_dev->f7_msg;
|
|
void __iomem *base = i2c_dev->base;
|
|
u32 cr1, cr2;
|
|
int ret;
|
|
|
|
f7_msg->addr = msg->addr;
|
|
f7_msg->buf = msg->buf;
|
|
f7_msg->count = msg->len;
|
|
f7_msg->result = 0;
|
|
f7_msg->stop = (i2c_dev->msg_id >= i2c_dev->msg_num - 1);
|
|
|
|
reinit_completion(&i2c_dev->complete);
|
|
|
|
cr1 = readl_relaxed(base + STM32F7_I2C_CR1);
|
|
cr2 = readl_relaxed(base + STM32F7_I2C_CR2);
|
|
|
|
/* Set transfer direction */
|
|
cr2 &= ~STM32F7_I2C_CR2_RD_WRN;
|
|
if (msg->flags & I2C_M_RD)
|
|
cr2 |= STM32F7_I2C_CR2_RD_WRN;
|
|
|
|
/* Set slave address */
|
|
cr2 &= ~(STM32F7_I2C_CR2_HEAD10R | STM32F7_I2C_CR2_ADD10);
|
|
if (msg->flags & I2C_M_TEN) {
|
|
cr2 &= ~STM32F7_I2C_CR2_SADD10_MASK;
|
|
cr2 |= STM32F7_I2C_CR2_SADD10(f7_msg->addr);
|
|
cr2 |= STM32F7_I2C_CR2_ADD10;
|
|
} else {
|
|
cr2 &= ~STM32F7_I2C_CR2_SADD7_MASK;
|
|
cr2 |= STM32F7_I2C_CR2_SADD7(f7_msg->addr);
|
|
}
|
|
|
|
/* Set nb bytes to transfer and reload if needed */
|
|
cr2 &= ~(STM32F7_I2C_CR2_NBYTES_MASK | STM32F7_I2C_CR2_RELOAD);
|
|
if (f7_msg->count > STM32F7_I2C_MAX_LEN) {
|
|
cr2 |= STM32F7_I2C_CR2_NBYTES(STM32F7_I2C_MAX_LEN);
|
|
cr2 |= STM32F7_I2C_CR2_RELOAD;
|
|
} else {
|
|
cr2 |= STM32F7_I2C_CR2_NBYTES(f7_msg->count);
|
|
}
|
|
|
|
/* Enable NACK, STOP, error and transfer complete interrupts */
|
|
cr1 |= STM32F7_I2C_CR1_ERRIE | STM32F7_I2C_CR1_TCIE |
|
|
STM32F7_I2C_CR1_STOPIE | STM32F7_I2C_CR1_NACKIE;
|
|
|
|
/* Clear DMA req and TX/RX interrupt */
|
|
cr1 &= ~(STM32F7_I2C_CR1_RXIE | STM32F7_I2C_CR1_TXIE |
|
|
STM32F7_I2C_CR1_RXDMAEN | STM32F7_I2C_CR1_TXDMAEN);
|
|
|
|
/* Configure DMA or enable RX/TX interrupt */
|
|
i2c_dev->use_dma = false;
|
|
if (i2c_dev->dma && f7_msg->count >= STM32F7_I2C_DMA_LEN_MIN) {
|
|
ret = stm32_i2c_prep_dma_xfer(i2c_dev->dev, i2c_dev->dma,
|
|
msg->flags & I2C_M_RD,
|
|
f7_msg->count, f7_msg->buf,
|
|
stm32f7_i2c_dma_callback,
|
|
i2c_dev);
|
|
if (!ret)
|
|
i2c_dev->use_dma = true;
|
|
else
|
|
dev_warn(i2c_dev->dev, "can't use DMA\n");
|
|
}
|
|
|
|
if (!i2c_dev->use_dma) {
|
|
if (msg->flags & I2C_M_RD)
|
|
cr1 |= STM32F7_I2C_CR1_RXIE;
|
|
else
|
|
cr1 |= STM32F7_I2C_CR1_TXIE;
|
|
} else {
|
|
if (msg->flags & I2C_M_RD)
|
|
cr1 |= STM32F7_I2C_CR1_RXDMAEN;
|
|
else
|
|
cr1 |= STM32F7_I2C_CR1_TXDMAEN;
|
|
}
|
|
|
|
/* Configure Start/Repeated Start */
|
|
cr2 |= STM32F7_I2C_CR2_START;
|
|
|
|
i2c_dev->master_mode = true;
|
|
|
|
/* Write configurations registers */
|
|
writel_relaxed(cr1, base + STM32F7_I2C_CR1);
|
|
writel_relaxed(cr2, base + STM32F7_I2C_CR2);
|
|
}
|
|
|
|
static int stm32f7_i2c_smbus_xfer_msg(struct stm32f7_i2c_dev *i2c_dev,
|
|
unsigned short flags, u8 command,
|
|
union i2c_smbus_data *data)
|
|
{
|
|
struct stm32f7_i2c_msg *f7_msg = &i2c_dev->f7_msg;
|
|
struct device *dev = i2c_dev->dev;
|
|
void __iomem *base = i2c_dev->base;
|
|
u32 cr1, cr2;
|
|
int i, ret;
|
|
|
|
f7_msg->result = 0;
|
|
reinit_completion(&i2c_dev->complete);
|
|
|
|
cr2 = readl_relaxed(base + STM32F7_I2C_CR2);
|
|
cr1 = readl_relaxed(base + STM32F7_I2C_CR1);
|
|
|
|
/* Set transfer direction */
|
|
cr2 &= ~STM32F7_I2C_CR2_RD_WRN;
|
|
if (f7_msg->read_write)
|
|
cr2 |= STM32F7_I2C_CR2_RD_WRN;
|
|
|
|
/* Set slave address */
|
|
cr2 &= ~(STM32F7_I2C_CR2_ADD10 | STM32F7_I2C_CR2_SADD7_MASK);
|
|
cr2 |= STM32F7_I2C_CR2_SADD7(f7_msg->addr);
|
|
|
|
f7_msg->smbus_buf[0] = command;
|
|
switch (f7_msg->size) {
|
|
case I2C_SMBUS_QUICK:
|
|
f7_msg->stop = true;
|
|
f7_msg->count = 0;
|
|
break;
|
|
case I2C_SMBUS_BYTE:
|
|
f7_msg->stop = true;
|
|
f7_msg->count = 1;
|
|
break;
|
|
case I2C_SMBUS_BYTE_DATA:
|
|
if (f7_msg->read_write) {
|
|
f7_msg->stop = false;
|
|
f7_msg->count = 1;
|
|
cr2 &= ~STM32F7_I2C_CR2_RD_WRN;
|
|
} else {
|
|
f7_msg->stop = true;
|
|
f7_msg->count = 2;
|
|
f7_msg->smbus_buf[1] = data->byte;
|
|
}
|
|
break;
|
|
case I2C_SMBUS_WORD_DATA:
|
|
if (f7_msg->read_write) {
|
|
f7_msg->stop = false;
|
|
f7_msg->count = 1;
|
|
cr2 &= ~STM32F7_I2C_CR2_RD_WRN;
|
|
} else {
|
|
f7_msg->stop = true;
|
|
f7_msg->count = 3;
|
|
f7_msg->smbus_buf[1] = data->word & 0xff;
|
|
f7_msg->smbus_buf[2] = data->word >> 8;
|
|
}
|
|
break;
|
|
case I2C_SMBUS_BLOCK_DATA:
|
|
if (f7_msg->read_write) {
|
|
f7_msg->stop = false;
|
|
f7_msg->count = 1;
|
|
cr2 &= ~STM32F7_I2C_CR2_RD_WRN;
|
|
} else {
|
|
f7_msg->stop = true;
|
|
if (data->block[0] > I2C_SMBUS_BLOCK_MAX ||
|
|
!data->block[0]) {
|
|
dev_err(dev, "Invalid block write size %d\n",
|
|
data->block[0]);
|
|
return -EINVAL;
|
|
}
|
|
f7_msg->count = data->block[0] + 2;
|
|
for (i = 1; i < f7_msg->count; i++)
|
|
f7_msg->smbus_buf[i] = data->block[i - 1];
|
|
}
|
|
break;
|
|
case I2C_SMBUS_PROC_CALL:
|
|
f7_msg->stop = false;
|
|
f7_msg->count = 3;
|
|
f7_msg->smbus_buf[1] = data->word & 0xff;
|
|
f7_msg->smbus_buf[2] = data->word >> 8;
|
|
cr2 &= ~STM32F7_I2C_CR2_RD_WRN;
|
|
f7_msg->read_write = I2C_SMBUS_READ;
|
|
break;
|
|
case I2C_SMBUS_BLOCK_PROC_CALL:
|
|
f7_msg->stop = false;
|
|
if (data->block[0] > I2C_SMBUS_BLOCK_MAX - 1) {
|
|
dev_err(dev, "Invalid block write size %d\n",
|
|
data->block[0]);
|
|
return -EINVAL;
|
|
}
|
|
f7_msg->count = data->block[0] + 2;
|
|
for (i = 1; i < f7_msg->count; i++)
|
|
f7_msg->smbus_buf[i] = data->block[i - 1];
|
|
cr2 &= ~STM32F7_I2C_CR2_RD_WRN;
|
|
f7_msg->read_write = I2C_SMBUS_READ;
|
|
break;
|
|
default:
|
|
dev_err(dev, "Unsupported smbus protocol %d\n", f7_msg->size);
|
|
return -EOPNOTSUPP;
|
|
}
|
|
|
|
f7_msg->buf = f7_msg->smbus_buf;
|
|
|
|
/* Configure PEC */
|
|
if ((flags & I2C_CLIENT_PEC) && f7_msg->size != I2C_SMBUS_QUICK) {
|
|
cr1 |= STM32F7_I2C_CR1_PECEN;
|
|
cr2 |= STM32F7_I2C_CR2_PECBYTE;
|
|
if (!f7_msg->read_write)
|
|
f7_msg->count++;
|
|
} else {
|
|
cr1 &= ~STM32F7_I2C_CR1_PECEN;
|
|
cr2 &= ~STM32F7_I2C_CR2_PECBYTE;
|
|
}
|
|
|
|
/* Set number of bytes to be transferred */
|
|
cr2 &= ~(STM32F7_I2C_CR2_NBYTES_MASK | STM32F7_I2C_CR2_RELOAD);
|
|
cr2 |= STM32F7_I2C_CR2_NBYTES(f7_msg->count);
|
|
|
|
/* Enable NACK, STOP, error and transfer complete interrupts */
|
|
cr1 |= STM32F7_I2C_CR1_ERRIE | STM32F7_I2C_CR1_TCIE |
|
|
STM32F7_I2C_CR1_STOPIE | STM32F7_I2C_CR1_NACKIE;
|
|
|
|
/* Clear DMA req and TX/RX interrupt */
|
|
cr1 &= ~(STM32F7_I2C_CR1_RXIE | STM32F7_I2C_CR1_TXIE |
|
|
STM32F7_I2C_CR1_RXDMAEN | STM32F7_I2C_CR1_TXDMAEN);
|
|
|
|
/* Configure DMA or enable RX/TX interrupt */
|
|
i2c_dev->use_dma = false;
|
|
if (i2c_dev->dma && f7_msg->count >= STM32F7_I2C_DMA_LEN_MIN) {
|
|
ret = stm32_i2c_prep_dma_xfer(i2c_dev->dev, i2c_dev->dma,
|
|
cr2 & STM32F7_I2C_CR2_RD_WRN,
|
|
f7_msg->count, f7_msg->buf,
|
|
stm32f7_i2c_dma_callback,
|
|
i2c_dev);
|
|
if (!ret)
|
|
i2c_dev->use_dma = true;
|
|
else
|
|
dev_warn(i2c_dev->dev, "can't use DMA\n");
|
|
}
|
|
|
|
if (!i2c_dev->use_dma) {
|
|
if (cr2 & STM32F7_I2C_CR2_RD_WRN)
|
|
cr1 |= STM32F7_I2C_CR1_RXIE;
|
|
else
|
|
cr1 |= STM32F7_I2C_CR1_TXIE;
|
|
} else {
|
|
if (cr2 & STM32F7_I2C_CR2_RD_WRN)
|
|
cr1 |= STM32F7_I2C_CR1_RXDMAEN;
|
|
else
|
|
cr1 |= STM32F7_I2C_CR1_TXDMAEN;
|
|
}
|
|
|
|
/* Set Start bit */
|
|
cr2 |= STM32F7_I2C_CR2_START;
|
|
|
|
i2c_dev->master_mode = true;
|
|
|
|
/* Write configurations registers */
|
|
writel_relaxed(cr1, base + STM32F7_I2C_CR1);
|
|
writel_relaxed(cr2, base + STM32F7_I2C_CR2);
|
|
|
|
return 0;
|
|
}
|
|
|
|
static void stm32f7_i2c_smbus_rep_start(struct stm32f7_i2c_dev *i2c_dev)
|
|
{
|
|
struct stm32f7_i2c_msg *f7_msg = &i2c_dev->f7_msg;
|
|
void __iomem *base = i2c_dev->base;
|
|
u32 cr1, cr2;
|
|
int ret;
|
|
|
|
cr2 = readl_relaxed(base + STM32F7_I2C_CR2);
|
|
cr1 = readl_relaxed(base + STM32F7_I2C_CR1);
|
|
|
|
/* Set transfer direction */
|
|
cr2 |= STM32F7_I2C_CR2_RD_WRN;
|
|
|
|
switch (f7_msg->size) {
|
|
case I2C_SMBUS_BYTE_DATA:
|
|
f7_msg->count = 1;
|
|
break;
|
|
case I2C_SMBUS_WORD_DATA:
|
|
case I2C_SMBUS_PROC_CALL:
|
|
f7_msg->count = 2;
|
|
break;
|
|
case I2C_SMBUS_BLOCK_DATA:
|
|
case I2C_SMBUS_BLOCK_PROC_CALL:
|
|
f7_msg->count = 1;
|
|
cr2 |= STM32F7_I2C_CR2_RELOAD;
|
|
break;
|
|
}
|
|
|
|
f7_msg->buf = f7_msg->smbus_buf;
|
|
f7_msg->stop = true;
|
|
|
|
/* Add one byte for PEC if needed */
|
|
if (cr1 & STM32F7_I2C_CR1_PECEN)
|
|
f7_msg->count++;
|
|
|
|
/* Set number of bytes to be transferred */
|
|
cr2 &= ~(STM32F7_I2C_CR2_NBYTES_MASK);
|
|
cr2 |= STM32F7_I2C_CR2_NBYTES(f7_msg->count);
|
|
|
|
/*
|
|
* Configure RX/TX interrupt:
|
|
*/
|
|
cr1 &= ~(STM32F7_I2C_CR1_RXIE | STM32F7_I2C_CR1_TXIE);
|
|
cr1 |= STM32F7_I2C_CR1_RXIE;
|
|
|
|
/*
|
|
* Configure DMA or enable RX/TX interrupt:
|
|
* For I2C_SMBUS_BLOCK_DATA and I2C_SMBUS_BLOCK_PROC_CALL we don't use
|
|
* dma as we don't know in advance how many data will be received
|
|
*/
|
|
cr1 &= ~(STM32F7_I2C_CR1_RXIE | STM32F7_I2C_CR1_TXIE |
|
|
STM32F7_I2C_CR1_RXDMAEN | STM32F7_I2C_CR1_TXDMAEN);
|
|
|
|
i2c_dev->use_dma = false;
|
|
if (i2c_dev->dma && f7_msg->count >= STM32F7_I2C_DMA_LEN_MIN &&
|
|
f7_msg->size != I2C_SMBUS_BLOCK_DATA &&
|
|
f7_msg->size != I2C_SMBUS_BLOCK_PROC_CALL) {
|
|
ret = stm32_i2c_prep_dma_xfer(i2c_dev->dev, i2c_dev->dma,
|
|
cr2 & STM32F7_I2C_CR2_RD_WRN,
|
|
f7_msg->count, f7_msg->buf,
|
|
stm32f7_i2c_dma_callback,
|
|
i2c_dev);
|
|
|
|
if (!ret)
|
|
i2c_dev->use_dma = true;
|
|
else
|
|
dev_warn(i2c_dev->dev, "can't use DMA\n");
|
|
}
|
|
|
|
if (!i2c_dev->use_dma)
|
|
cr1 |= STM32F7_I2C_CR1_RXIE;
|
|
else
|
|
cr1 |= STM32F7_I2C_CR1_RXDMAEN;
|
|
|
|
/* Configure Repeated Start */
|
|
cr2 |= STM32F7_I2C_CR2_START;
|
|
|
|
/* Write configurations registers */
|
|
writel_relaxed(cr1, base + STM32F7_I2C_CR1);
|
|
writel_relaxed(cr2, base + STM32F7_I2C_CR2);
|
|
}
|
|
|
|
static int stm32f7_i2c_smbus_check_pec(struct stm32f7_i2c_dev *i2c_dev)
|
|
{
|
|
struct stm32f7_i2c_msg *f7_msg = &i2c_dev->f7_msg;
|
|
u8 count, internal_pec, received_pec;
|
|
|
|
internal_pec = readl_relaxed(i2c_dev->base + STM32F7_I2C_PECR);
|
|
|
|
switch (f7_msg->size) {
|
|
case I2C_SMBUS_BYTE:
|
|
case I2C_SMBUS_BYTE_DATA:
|
|
received_pec = f7_msg->smbus_buf[1];
|
|
break;
|
|
case I2C_SMBUS_WORD_DATA:
|
|
case I2C_SMBUS_PROC_CALL:
|
|
received_pec = f7_msg->smbus_buf[2];
|
|
break;
|
|
case I2C_SMBUS_BLOCK_DATA:
|
|
case I2C_SMBUS_BLOCK_PROC_CALL:
|
|
count = f7_msg->smbus_buf[0];
|
|
received_pec = f7_msg->smbus_buf[count];
|
|
break;
|
|
default:
|
|
dev_err(i2c_dev->dev, "Unsupported smbus protocol for PEC\n");
|
|
return -EINVAL;
|
|
}
|
|
|
|
if (internal_pec != received_pec) {
|
|
dev_err(i2c_dev->dev, "Bad PEC 0x%02x vs. 0x%02x\n",
|
|
internal_pec, received_pec);
|
|
return -EBADMSG;
|
|
}
|
|
|
|
return 0;
|
|
}
|
|
|
|
static bool stm32f7_i2c_is_addr_match(struct i2c_client *slave, u32 addcode)
|
|
{
|
|
u32 addr;
|
|
|
|
if (!slave)
|
|
return false;
|
|
|
|
if (slave->flags & I2C_CLIENT_TEN) {
|
|
/*
|
|
* For 10-bit addr, addcode = 11110XY with
|
|
* X = Bit 9 of slave address
|
|
* Y = Bit 8 of slave address
|
|
*/
|
|
addr = slave->addr >> 8;
|
|
addr |= 0x78;
|
|
if (addr == addcode)
|
|
return true;
|
|
} else {
|
|
addr = slave->addr & 0x7f;
|
|
if (addr == addcode)
|
|
return true;
|
|
}
|
|
|
|
return false;
|
|
}
|
|
|
|
static void stm32f7_i2c_slave_start(struct stm32f7_i2c_dev *i2c_dev)
|
|
{
|
|
struct i2c_client *slave = i2c_dev->slave_running;
|
|
void __iomem *base = i2c_dev->base;
|
|
u32 mask;
|
|
u8 value = 0;
|
|
|
|
if (i2c_dev->slave_dir) {
|
|
/* Notify i2c slave that new read transfer is starting */
|
|
i2c_slave_event(slave, I2C_SLAVE_READ_REQUESTED, &value);
|
|
|
|
/*
|
|
* Disable slave TX config in case of I2C combined message
|
|
* (I2C Write followed by I2C Read)
|
|
*/
|
|
mask = STM32F7_I2C_CR2_RELOAD;
|
|
stm32f7_i2c_clr_bits(base + STM32F7_I2C_CR2, mask);
|
|
mask = STM32F7_I2C_CR1_SBC | STM32F7_I2C_CR1_RXIE |
|
|
STM32F7_I2C_CR1_TCIE;
|
|
stm32f7_i2c_clr_bits(base + STM32F7_I2C_CR1, mask);
|
|
|
|
/* Enable TX empty, STOP, NACK interrupts */
|
|
mask = STM32F7_I2C_CR1_STOPIE | STM32F7_I2C_CR1_NACKIE |
|
|
STM32F7_I2C_CR1_TXIE;
|
|
stm32f7_i2c_set_bits(base + STM32F7_I2C_CR1, mask);
|
|
|
|
} else {
|
|
/* Notify i2c slave that new write transfer is starting */
|
|
i2c_slave_event(slave, I2C_SLAVE_WRITE_REQUESTED, &value);
|
|
|
|
/* Set reload mode to be able to ACK/NACK each received byte */
|
|
mask = STM32F7_I2C_CR2_RELOAD;
|
|
stm32f7_i2c_set_bits(base + STM32F7_I2C_CR2, mask);
|
|
|
|
/*
|
|
* Set STOP, NACK, RX empty and transfer complete interrupts.*
|
|
* Set Slave Byte Control to be able to ACK/NACK each data
|
|
* byte received
|
|
*/
|
|
mask = STM32F7_I2C_CR1_STOPIE | STM32F7_I2C_CR1_NACKIE |
|
|
STM32F7_I2C_CR1_SBC | STM32F7_I2C_CR1_RXIE |
|
|
STM32F7_I2C_CR1_TCIE;
|
|
stm32f7_i2c_set_bits(base + STM32F7_I2C_CR1, mask);
|
|
}
|
|
}
|
|
|
|
static void stm32f7_i2c_slave_addr(struct stm32f7_i2c_dev *i2c_dev)
|
|
{
|
|
void __iomem *base = i2c_dev->base;
|
|
u32 isr, addcode, dir, mask;
|
|
int i;
|
|
|
|
isr = readl_relaxed(i2c_dev->base + STM32F7_I2C_ISR);
|
|
addcode = STM32F7_I2C_ISR_ADDCODE_GET(isr);
|
|
dir = isr & STM32F7_I2C_ISR_DIR;
|
|
|
|
for (i = 0; i < STM32F7_I2C_MAX_SLAVE; i++) {
|
|
if (stm32f7_i2c_is_addr_match(i2c_dev->slave[i], addcode)) {
|
|
i2c_dev->slave_running = i2c_dev->slave[i];
|
|
i2c_dev->slave_dir = dir;
|
|
|
|
/* Start I2C slave processing */
|
|
stm32f7_i2c_slave_start(i2c_dev);
|
|
|
|
/* Clear ADDR flag */
|
|
mask = STM32F7_I2C_ICR_ADDRCF;
|
|
writel_relaxed(mask, base + STM32F7_I2C_ICR);
|
|
break;
|
|
}
|
|
}
|
|
}
|
|
|
|
static int stm32f7_i2c_get_slave_id(struct stm32f7_i2c_dev *i2c_dev,
|
|
struct i2c_client *slave, int *id)
|
|
{
|
|
int i;
|
|
|
|
for (i = 0; i < STM32F7_I2C_MAX_SLAVE; i++) {
|
|
if (i2c_dev->slave[i] == slave) {
|
|
*id = i;
|
|
return 0;
|
|
}
|
|
}
|
|
|
|
dev_err(i2c_dev->dev, "Slave 0x%x not registered\n", slave->addr);
|
|
|
|
return -ENODEV;
|
|
}
|
|
|
|
static int stm32f7_i2c_get_free_slave_id(struct stm32f7_i2c_dev *i2c_dev,
|
|
struct i2c_client *slave, int *id)
|
|
{
|
|
struct device *dev = i2c_dev->dev;
|
|
int i;
|
|
|
|
/*
|
|
* slave[0] supports 7-bit and 10-bit slave address
|
|
* slave[1] supports 7-bit slave address only
|
|
*/
|
|
for (i = 0; i < STM32F7_I2C_MAX_SLAVE; i++) {
|
|
if (i == 1 && (slave->flags & I2C_CLIENT_PEC))
|
|
continue;
|
|
if (!i2c_dev->slave[i]) {
|
|
*id = i;
|
|
return 0;
|
|
}
|
|
}
|
|
|
|
dev_err(dev, "Slave 0x%x could not be registered\n", slave->addr);
|
|
|
|
return -EINVAL;
|
|
}
|
|
|
|
static bool stm32f7_i2c_is_slave_registered(struct stm32f7_i2c_dev *i2c_dev)
|
|
{
|
|
int i;
|
|
|
|
for (i = 0; i < STM32F7_I2C_MAX_SLAVE; i++) {
|
|
if (i2c_dev->slave[i])
|
|
return true;
|
|
}
|
|
|
|
return false;
|
|
}
|
|
|
|
static bool stm32f7_i2c_is_slave_busy(struct stm32f7_i2c_dev *i2c_dev)
|
|
{
|
|
int i, busy;
|
|
|
|
busy = 0;
|
|
for (i = 0; i < STM32F7_I2C_MAX_SLAVE; i++) {
|
|
if (i2c_dev->slave[i])
|
|
busy++;
|
|
}
|
|
|
|
return i == busy;
|
|
}
|
|
|
|
static irqreturn_t stm32f7_i2c_slave_isr_event(struct stm32f7_i2c_dev *i2c_dev)
|
|
{
|
|
void __iomem *base = i2c_dev->base;
|
|
u32 cr2, status, mask;
|
|
u8 val;
|
|
int ret;
|
|
|
|
status = readl_relaxed(i2c_dev->base + STM32F7_I2C_ISR);
|
|
|
|
/* Slave transmitter mode */
|
|
if (status & STM32F7_I2C_ISR_TXIS) {
|
|
i2c_slave_event(i2c_dev->slave_running,
|
|
I2C_SLAVE_READ_PROCESSED,
|
|
&val);
|
|
|
|
/* Write data byte */
|
|
writel_relaxed(val, base + STM32F7_I2C_TXDR);
|
|
}
|
|
|
|
/* Transfer Complete Reload for Slave receiver mode */
|
|
if (status & STM32F7_I2C_ISR_TCR || status & STM32F7_I2C_ISR_RXNE) {
|
|
/*
|
|
* Read data byte then set NBYTES to receive next byte or NACK
|
|
* the current received byte
|
|
*/
|
|
val = readb_relaxed(i2c_dev->base + STM32F7_I2C_RXDR);
|
|
ret = i2c_slave_event(i2c_dev->slave_running,
|
|
I2C_SLAVE_WRITE_RECEIVED,
|
|
&val);
|
|
if (!ret) {
|
|
cr2 = readl_relaxed(i2c_dev->base + STM32F7_I2C_CR2);
|
|
cr2 |= STM32F7_I2C_CR2_NBYTES(1);
|
|
writel_relaxed(cr2, i2c_dev->base + STM32F7_I2C_CR2);
|
|
} else {
|
|
mask = STM32F7_I2C_CR2_NACK;
|
|
stm32f7_i2c_set_bits(base + STM32F7_I2C_CR2, mask);
|
|
}
|
|
}
|
|
|
|
/* NACK received */
|
|
if (status & STM32F7_I2C_ISR_NACKF) {
|
|
dev_dbg(i2c_dev->dev, "<%s>: Receive NACK\n", __func__);
|
|
writel_relaxed(STM32F7_I2C_ICR_NACKCF, base + STM32F7_I2C_ICR);
|
|
}
|
|
|
|
/* STOP received */
|
|
if (status & STM32F7_I2C_ISR_STOPF) {
|
|
/* Disable interrupts */
|
|
stm32f7_i2c_disable_irq(i2c_dev, STM32F7_I2C_XFER_IRQ_MASK);
|
|
|
|
if (i2c_dev->slave_dir) {
|
|
/*
|
|
* Flush TX buffer in order to not used the byte in
|
|
* TXDR for the next transfer
|
|
*/
|
|
mask = STM32F7_I2C_ISR_TXE;
|
|
stm32f7_i2c_set_bits(base + STM32F7_I2C_ISR, mask);
|
|
}
|
|
|
|
/* Clear STOP flag */
|
|
writel_relaxed(STM32F7_I2C_ICR_STOPCF, base + STM32F7_I2C_ICR);
|
|
|
|
/* Notify i2c slave that a STOP flag has been detected */
|
|
i2c_slave_event(i2c_dev->slave_running, I2C_SLAVE_STOP, &val);
|
|
|
|
i2c_dev->slave_running = NULL;
|
|
}
|
|
|
|
/* Address match received */
|
|
if (status & STM32F7_I2C_ISR_ADDR)
|
|
stm32f7_i2c_slave_addr(i2c_dev);
|
|
|
|
return IRQ_HANDLED;
|
|
}
|
|
|
|
static irqreturn_t stm32f7_i2c_isr_event(int irq, void *data)
|
|
{
|
|
struct stm32f7_i2c_dev *i2c_dev = data;
|
|
struct stm32f7_i2c_msg *f7_msg = &i2c_dev->f7_msg;
|
|
void __iomem *base = i2c_dev->base;
|
|
u32 status, mask;
|
|
int ret = IRQ_HANDLED;
|
|
|
|
/* Check if the interrupt if for a slave device */
|
|
if (!i2c_dev->master_mode) {
|
|
ret = stm32f7_i2c_slave_isr_event(i2c_dev);
|
|
return ret;
|
|
}
|
|
|
|
status = readl_relaxed(i2c_dev->base + STM32F7_I2C_ISR);
|
|
|
|
/* Tx empty */
|
|
if (status & STM32F7_I2C_ISR_TXIS)
|
|
stm32f7_i2c_write_tx_data(i2c_dev);
|
|
|
|
/* RX not empty */
|
|
if (status & STM32F7_I2C_ISR_RXNE)
|
|
stm32f7_i2c_read_rx_data(i2c_dev);
|
|
|
|
/* NACK received */
|
|
if (status & STM32F7_I2C_ISR_NACKF) {
|
|
dev_dbg(i2c_dev->dev, "<%s>: Receive NACK\n", __func__);
|
|
writel_relaxed(STM32F7_I2C_ICR_NACKCF, base + STM32F7_I2C_ICR);
|
|
f7_msg->result = -ENXIO;
|
|
}
|
|
|
|
/* STOP detection flag */
|
|
if (status & STM32F7_I2C_ISR_STOPF) {
|
|
/* Disable interrupts */
|
|
if (stm32f7_i2c_is_slave_registered(i2c_dev))
|
|
mask = STM32F7_I2C_XFER_IRQ_MASK;
|
|
else
|
|
mask = STM32F7_I2C_ALL_IRQ_MASK;
|
|
stm32f7_i2c_disable_irq(i2c_dev, mask);
|
|
|
|
/* Clear STOP flag */
|
|
writel_relaxed(STM32F7_I2C_ICR_STOPCF, base + STM32F7_I2C_ICR);
|
|
|
|
if (i2c_dev->use_dma) {
|
|
ret = IRQ_WAKE_THREAD;
|
|
} else {
|
|
i2c_dev->master_mode = false;
|
|
complete(&i2c_dev->complete);
|
|
}
|
|
}
|
|
|
|
/* Transfer complete */
|
|
if (status & STM32F7_I2C_ISR_TC) {
|
|
if (f7_msg->stop) {
|
|
mask = STM32F7_I2C_CR2_STOP;
|
|
stm32f7_i2c_set_bits(base + STM32F7_I2C_CR2, mask);
|
|
} else if (i2c_dev->use_dma) {
|
|
ret = IRQ_WAKE_THREAD;
|
|
} else if (f7_msg->smbus) {
|
|
stm32f7_i2c_smbus_rep_start(i2c_dev);
|
|
} else {
|
|
i2c_dev->msg_id++;
|
|
i2c_dev->msg++;
|
|
stm32f7_i2c_xfer_msg(i2c_dev, i2c_dev->msg);
|
|
}
|
|
}
|
|
|
|
if (status & STM32F7_I2C_ISR_TCR) {
|
|
if (f7_msg->smbus)
|
|
stm32f7_i2c_smbus_reload(i2c_dev);
|
|
else
|
|
stm32f7_i2c_reload(i2c_dev);
|
|
}
|
|
|
|
return ret;
|
|
}
|
|
|
|
static irqreturn_t stm32f7_i2c_isr_event_thread(int irq, void *data)
|
|
{
|
|
struct stm32f7_i2c_dev *i2c_dev = data;
|
|
struct stm32f7_i2c_msg *f7_msg = &i2c_dev->f7_msg;
|
|
struct stm32_i2c_dma *dma = i2c_dev->dma;
|
|
u32 status;
|
|
int ret;
|
|
|
|
/*
|
|
* Wait for dma transfer completion before sending next message or
|
|
* notity the end of xfer to the client
|
|
*/
|
|
ret = wait_for_completion_timeout(&i2c_dev->dma->dma_complete, HZ);
|
|
if (!ret) {
|
|
dev_dbg(i2c_dev->dev, "<%s>: Timed out\n", __func__);
|
|
stm32f7_i2c_disable_dma_req(i2c_dev);
|
|
dmaengine_terminate_all(dma->chan_using);
|
|
f7_msg->result = -ETIMEDOUT;
|
|
}
|
|
|
|
status = readl_relaxed(i2c_dev->base + STM32F7_I2C_ISR);
|
|
|
|
if (status & STM32F7_I2C_ISR_TC) {
|
|
if (f7_msg->smbus) {
|
|
stm32f7_i2c_smbus_rep_start(i2c_dev);
|
|
} else {
|
|
i2c_dev->msg_id++;
|
|
i2c_dev->msg++;
|
|
stm32f7_i2c_xfer_msg(i2c_dev, i2c_dev->msg);
|
|
}
|
|
} else {
|
|
i2c_dev->master_mode = false;
|
|
complete(&i2c_dev->complete);
|
|
}
|
|
|
|
return IRQ_HANDLED;
|
|
}
|
|
|
|
static irqreturn_t stm32f7_i2c_isr_error(int irq, void *data)
|
|
{
|
|
struct stm32f7_i2c_dev *i2c_dev = data;
|
|
struct stm32f7_i2c_msg *f7_msg = &i2c_dev->f7_msg;
|
|
void __iomem *base = i2c_dev->base;
|
|
struct device *dev = i2c_dev->dev;
|
|
struct stm32_i2c_dma *dma = i2c_dev->dma;
|
|
u32 mask, status;
|
|
|
|
status = readl_relaxed(i2c_dev->base + STM32F7_I2C_ISR);
|
|
|
|
/* Bus error */
|
|
if (status & STM32F7_I2C_ISR_BERR) {
|
|
dev_err(dev, "<%s>: Bus error\n", __func__);
|
|
writel_relaxed(STM32F7_I2C_ICR_BERRCF, base + STM32F7_I2C_ICR);
|
|
stm32f7_i2c_release_bus(&i2c_dev->adap);
|
|
f7_msg->result = -EIO;
|
|
}
|
|
|
|
/* Arbitration loss */
|
|
if (status & STM32F7_I2C_ISR_ARLO) {
|
|
dev_dbg(dev, "<%s>: Arbitration loss\n", __func__);
|
|
writel_relaxed(STM32F7_I2C_ICR_ARLOCF, base + STM32F7_I2C_ICR);
|
|
f7_msg->result = -EAGAIN;
|
|
}
|
|
|
|
if (status & STM32F7_I2C_ISR_PECERR) {
|
|
dev_err(dev, "<%s>: PEC error in reception\n", __func__);
|
|
writel_relaxed(STM32F7_I2C_ICR_PECCF, base + STM32F7_I2C_ICR);
|
|
f7_msg->result = -EINVAL;
|
|
}
|
|
|
|
/* Disable interrupts */
|
|
if (stm32f7_i2c_is_slave_registered(i2c_dev))
|
|
mask = STM32F7_I2C_XFER_IRQ_MASK;
|
|
else
|
|
mask = STM32F7_I2C_ALL_IRQ_MASK;
|
|
stm32f7_i2c_disable_irq(i2c_dev, mask);
|
|
|
|
/* Disable dma */
|
|
if (i2c_dev->use_dma) {
|
|
stm32f7_i2c_disable_dma_req(i2c_dev);
|
|
dmaengine_terminate_all(dma->chan_using);
|
|
}
|
|
|
|
i2c_dev->master_mode = false;
|
|
complete(&i2c_dev->complete);
|
|
|
|
return IRQ_HANDLED;
|
|
}
|
|
|
|
static int stm32f7_i2c_xfer(struct i2c_adapter *i2c_adap,
|
|
struct i2c_msg msgs[], int num)
|
|
{
|
|
struct stm32f7_i2c_dev *i2c_dev = i2c_get_adapdata(i2c_adap);
|
|
struct stm32f7_i2c_msg *f7_msg = &i2c_dev->f7_msg;
|
|
struct stm32_i2c_dma *dma = i2c_dev->dma;
|
|
unsigned long time_left;
|
|
int ret;
|
|
|
|
i2c_dev->msg = msgs;
|
|
i2c_dev->msg_num = num;
|
|
i2c_dev->msg_id = 0;
|
|
f7_msg->smbus = false;
|
|
|
|
ret = pm_runtime_get_sync(i2c_dev->dev);
|
|
if (ret < 0)
|
|
return ret;
|
|
|
|
ret = stm32f7_i2c_wait_free_bus(i2c_dev);
|
|
if (ret)
|
|
goto pm_free;
|
|
|
|
stm32f7_i2c_xfer_msg(i2c_dev, msgs);
|
|
|
|
time_left = wait_for_completion_timeout(&i2c_dev->complete,
|
|
i2c_dev->adap.timeout);
|
|
ret = f7_msg->result;
|
|
|
|
if (!time_left) {
|
|
dev_dbg(i2c_dev->dev, "Access to slave 0x%x timed out\n",
|
|
i2c_dev->msg->addr);
|
|
if (i2c_dev->use_dma)
|
|
dmaengine_terminate_all(dma->chan_using);
|
|
ret = -ETIMEDOUT;
|
|
}
|
|
|
|
pm_free:
|
|
pm_runtime_mark_last_busy(i2c_dev->dev);
|
|
pm_runtime_put_autosuspend(i2c_dev->dev);
|
|
|
|
return (ret < 0) ? ret : num;
|
|
}
|
|
|
|
static int stm32f7_i2c_smbus_xfer(struct i2c_adapter *adapter, u16 addr,
|
|
unsigned short flags, char read_write,
|
|
u8 command, int size,
|
|
union i2c_smbus_data *data)
|
|
{
|
|
struct stm32f7_i2c_dev *i2c_dev = i2c_get_adapdata(adapter);
|
|
struct stm32f7_i2c_msg *f7_msg = &i2c_dev->f7_msg;
|
|
struct stm32_i2c_dma *dma = i2c_dev->dma;
|
|
struct device *dev = i2c_dev->dev;
|
|
unsigned long timeout;
|
|
int i, ret;
|
|
|
|
f7_msg->addr = addr;
|
|
f7_msg->size = size;
|
|
f7_msg->read_write = read_write;
|
|
f7_msg->smbus = true;
|
|
|
|
ret = pm_runtime_get_sync(dev);
|
|
if (ret < 0)
|
|
return ret;
|
|
|
|
ret = stm32f7_i2c_wait_free_bus(i2c_dev);
|
|
if (ret)
|
|
goto pm_free;
|
|
|
|
ret = stm32f7_i2c_smbus_xfer_msg(i2c_dev, flags, command, data);
|
|
if (ret)
|
|
goto pm_free;
|
|
|
|
timeout = wait_for_completion_timeout(&i2c_dev->complete,
|
|
i2c_dev->adap.timeout);
|
|
ret = f7_msg->result;
|
|
if (ret)
|
|
goto pm_free;
|
|
|
|
if (!timeout) {
|
|
dev_dbg(dev, "Access to slave 0x%x timed out\n", f7_msg->addr);
|
|
if (i2c_dev->use_dma)
|
|
dmaengine_terminate_all(dma->chan_using);
|
|
ret = -ETIMEDOUT;
|
|
goto pm_free;
|
|
}
|
|
|
|
/* Check PEC */
|
|
if ((flags & I2C_CLIENT_PEC) && size != I2C_SMBUS_QUICK && read_write) {
|
|
ret = stm32f7_i2c_smbus_check_pec(i2c_dev);
|
|
if (ret)
|
|
goto pm_free;
|
|
}
|
|
|
|
if (read_write && size != I2C_SMBUS_QUICK) {
|
|
switch (size) {
|
|
case I2C_SMBUS_BYTE:
|
|
case I2C_SMBUS_BYTE_DATA:
|
|
data->byte = f7_msg->smbus_buf[0];
|
|
break;
|
|
case I2C_SMBUS_WORD_DATA:
|
|
case I2C_SMBUS_PROC_CALL:
|
|
data->word = f7_msg->smbus_buf[0] |
|
|
(f7_msg->smbus_buf[1] << 8);
|
|
break;
|
|
case I2C_SMBUS_BLOCK_DATA:
|
|
case I2C_SMBUS_BLOCK_PROC_CALL:
|
|
for (i = 0; i <= f7_msg->smbus_buf[0]; i++)
|
|
data->block[i] = f7_msg->smbus_buf[i];
|
|
break;
|
|
default:
|
|
dev_err(dev, "Unsupported smbus transaction\n");
|
|
ret = -EINVAL;
|
|
}
|
|
}
|
|
|
|
pm_free:
|
|
pm_runtime_mark_last_busy(dev);
|
|
pm_runtime_put_autosuspend(dev);
|
|
return ret;
|
|
}
|
|
|
|
static int stm32f7_i2c_reg_slave(struct i2c_client *slave)
|
|
{
|
|
struct stm32f7_i2c_dev *i2c_dev = i2c_get_adapdata(slave->adapter);
|
|
void __iomem *base = i2c_dev->base;
|
|
struct device *dev = i2c_dev->dev;
|
|
u32 oar1, oar2, mask;
|
|
int id, ret;
|
|
|
|
if (slave->flags & I2C_CLIENT_PEC) {
|
|
dev_err(dev, "SMBus PEC not supported in slave mode\n");
|
|
return -EINVAL;
|
|
}
|
|
|
|
if (stm32f7_i2c_is_slave_busy(i2c_dev)) {
|
|
dev_err(dev, "Too much slave registered\n");
|
|
return -EBUSY;
|
|
}
|
|
|
|
ret = stm32f7_i2c_get_free_slave_id(i2c_dev, slave, &id);
|
|
if (ret)
|
|
return ret;
|
|
|
|
ret = pm_runtime_get_sync(dev);
|
|
if (ret < 0)
|
|
return ret;
|
|
|
|
if (id == 0) {
|
|
/* Configure Own Address 1 */
|
|
oar1 = readl_relaxed(i2c_dev->base + STM32F7_I2C_OAR1);
|
|
oar1 &= ~STM32F7_I2C_OAR1_MASK;
|
|
if (slave->flags & I2C_CLIENT_TEN) {
|
|
oar1 |= STM32F7_I2C_OAR1_OA1_10(slave->addr);
|
|
oar1 |= STM32F7_I2C_OAR1_OA1MODE;
|
|
} else {
|
|
oar1 |= STM32F7_I2C_OAR1_OA1_7(slave->addr);
|
|
}
|
|
oar1 |= STM32F7_I2C_OAR1_OA1EN;
|
|
i2c_dev->slave[id] = slave;
|
|
writel_relaxed(oar1, i2c_dev->base + STM32F7_I2C_OAR1);
|
|
} else if (id == 1) {
|
|
/* Configure Own Address 2 */
|
|
oar2 = readl_relaxed(i2c_dev->base + STM32F7_I2C_OAR2);
|
|
oar2 &= ~STM32F7_I2C_OAR2_MASK;
|
|
if (slave->flags & I2C_CLIENT_TEN) {
|
|
ret = -EOPNOTSUPP;
|
|
goto pm_free;
|
|
}
|
|
|
|
oar2 |= STM32F7_I2C_OAR2_OA2_7(slave->addr);
|
|
oar2 |= STM32F7_I2C_OAR2_OA2EN;
|
|
i2c_dev->slave[id] = slave;
|
|
writel_relaxed(oar2, i2c_dev->base + STM32F7_I2C_OAR2);
|
|
} else {
|
|
ret = -ENODEV;
|
|
goto pm_free;
|
|
}
|
|
|
|
/* Enable ACK */
|
|
stm32f7_i2c_clr_bits(base + STM32F7_I2C_CR2, STM32F7_I2C_CR2_NACK);
|
|
|
|
/* Enable Address match interrupt, error interrupt and enable I2C */
|
|
mask = STM32F7_I2C_CR1_ADDRIE | STM32F7_I2C_CR1_ERRIE |
|
|
STM32F7_I2C_CR1_PE;
|
|
stm32f7_i2c_set_bits(base + STM32F7_I2C_CR1, mask);
|
|
|
|
ret = 0;
|
|
pm_free:
|
|
pm_runtime_mark_last_busy(dev);
|
|
pm_runtime_put_autosuspend(dev);
|
|
|
|
return ret;
|
|
}
|
|
|
|
static int stm32f7_i2c_unreg_slave(struct i2c_client *slave)
|
|
{
|
|
struct stm32f7_i2c_dev *i2c_dev = i2c_get_adapdata(slave->adapter);
|
|
void __iomem *base = i2c_dev->base;
|
|
u32 mask;
|
|
int id, ret;
|
|
|
|
ret = stm32f7_i2c_get_slave_id(i2c_dev, slave, &id);
|
|
if (ret)
|
|
return ret;
|
|
|
|
WARN_ON(!i2c_dev->slave[id]);
|
|
|
|
ret = pm_runtime_get_sync(i2c_dev->dev);
|
|
if (ret < 0)
|
|
return ret;
|
|
|
|
if (id == 0) {
|
|
mask = STM32F7_I2C_OAR1_OA1EN;
|
|
stm32f7_i2c_clr_bits(base + STM32F7_I2C_OAR1, mask);
|
|
} else {
|
|
mask = STM32F7_I2C_OAR2_OA2EN;
|
|
stm32f7_i2c_clr_bits(base + STM32F7_I2C_OAR2, mask);
|
|
}
|
|
|
|
i2c_dev->slave[id] = NULL;
|
|
|
|
if (!(stm32f7_i2c_is_slave_registered(i2c_dev)))
|
|
stm32f7_i2c_disable_irq(i2c_dev, STM32F7_I2C_ALL_IRQ_MASK);
|
|
|
|
pm_runtime_mark_last_busy(i2c_dev->dev);
|
|
pm_runtime_put_autosuspend(i2c_dev->dev);
|
|
|
|
return 0;
|
|
}
|
|
|
|
static int stm32f7_i2c_setup_fm_plus_bits(struct platform_device *pdev,
|
|
struct stm32f7_i2c_dev *i2c_dev)
|
|
{
|
|
struct device_node *np = pdev->dev.of_node;
|
|
int ret;
|
|
u32 reg, mask;
|
|
|
|
i2c_dev->regmap = syscon_regmap_lookup_by_phandle(np, "st,syscfg-fmp");
|
|
if (IS_ERR(i2c_dev->regmap)) {
|
|
/* Optional */
|
|
return 0;
|
|
}
|
|
|
|
ret = of_property_read_u32_index(np, "st,syscfg-fmp", 1, ®);
|
|
if (ret)
|
|
return ret;
|
|
|
|
ret = of_property_read_u32_index(np, "st,syscfg-fmp", 2, &mask);
|
|
if (ret)
|
|
return ret;
|
|
|
|
return regmap_update_bits(i2c_dev->regmap, reg, mask, mask);
|
|
}
|
|
|
|
static u32 stm32f7_i2c_func(struct i2c_adapter *adap)
|
|
{
|
|
return I2C_FUNC_I2C | I2C_FUNC_10BIT_ADDR | I2C_FUNC_SLAVE |
|
|
I2C_FUNC_SMBUS_QUICK | I2C_FUNC_SMBUS_BYTE |
|
|
I2C_FUNC_SMBUS_BYTE_DATA | I2C_FUNC_SMBUS_WORD_DATA |
|
|
I2C_FUNC_SMBUS_BLOCK_DATA | I2C_FUNC_SMBUS_BLOCK_PROC_CALL |
|
|
I2C_FUNC_SMBUS_PROC_CALL | I2C_FUNC_SMBUS_PEC;
|
|
}
|
|
|
|
static struct i2c_algorithm stm32f7_i2c_algo = {
|
|
.master_xfer = stm32f7_i2c_xfer,
|
|
.smbus_xfer = stm32f7_i2c_smbus_xfer,
|
|
.functionality = stm32f7_i2c_func,
|
|
.reg_slave = stm32f7_i2c_reg_slave,
|
|
.unreg_slave = stm32f7_i2c_unreg_slave,
|
|
};
|
|
|
|
static int stm32f7_i2c_probe(struct platform_device *pdev)
|
|
{
|
|
struct device_node *np = pdev->dev.of_node;
|
|
struct stm32f7_i2c_dev *i2c_dev;
|
|
const struct stm32f7_i2c_setup *setup;
|
|
struct resource *res;
|
|
u32 irq_error, irq_event, clk_rate, rise_time, fall_time;
|
|
struct i2c_adapter *adap;
|
|
struct reset_control *rst;
|
|
dma_addr_t phy_addr;
|
|
int ret;
|
|
|
|
i2c_dev = devm_kzalloc(&pdev->dev, sizeof(*i2c_dev), GFP_KERNEL);
|
|
if (!i2c_dev)
|
|
return -ENOMEM;
|
|
|
|
res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
|
|
i2c_dev->base = devm_ioremap_resource(&pdev->dev, res);
|
|
if (IS_ERR(i2c_dev->base))
|
|
return PTR_ERR(i2c_dev->base);
|
|
phy_addr = (dma_addr_t)res->start;
|
|
|
|
irq_event = irq_of_parse_and_map(np, 0);
|
|
if (!irq_event) {
|
|
dev_err(&pdev->dev, "IRQ event missing or invalid\n");
|
|
return -EINVAL;
|
|
}
|
|
|
|
irq_error = irq_of_parse_and_map(np, 1);
|
|
if (!irq_error) {
|
|
dev_err(&pdev->dev, "IRQ error missing or invalid\n");
|
|
return -EINVAL;
|
|
}
|
|
|
|
i2c_dev->clk = devm_clk_get(&pdev->dev, NULL);
|
|
if (IS_ERR(i2c_dev->clk)) {
|
|
dev_err(&pdev->dev, "Error: Missing controller clock\n");
|
|
return PTR_ERR(i2c_dev->clk);
|
|
}
|
|
|
|
ret = clk_prepare_enable(i2c_dev->clk);
|
|
if (ret) {
|
|
dev_err(&pdev->dev, "Failed to prepare_enable clock\n");
|
|
return ret;
|
|
}
|
|
|
|
i2c_dev->speed = STM32_I2C_SPEED_STANDARD;
|
|
ret = device_property_read_u32(&pdev->dev, "clock-frequency",
|
|
&clk_rate);
|
|
if (!ret && clk_rate >= 1000000) {
|
|
i2c_dev->speed = STM32_I2C_SPEED_FAST_PLUS;
|
|
ret = stm32f7_i2c_setup_fm_plus_bits(pdev, i2c_dev);
|
|
if (ret)
|
|
goto clk_free;
|
|
} else if (!ret && clk_rate >= 400000) {
|
|
i2c_dev->speed = STM32_I2C_SPEED_FAST;
|
|
} else if (!ret && clk_rate >= 100000) {
|
|
i2c_dev->speed = STM32_I2C_SPEED_STANDARD;
|
|
}
|
|
|
|
rst = devm_reset_control_get(&pdev->dev, NULL);
|
|
if (IS_ERR(rst)) {
|
|
dev_err(&pdev->dev, "Error: Missing controller reset\n");
|
|
ret = PTR_ERR(rst);
|
|
goto clk_free;
|
|
}
|
|
reset_control_assert(rst);
|
|
udelay(2);
|
|
reset_control_deassert(rst);
|
|
|
|
i2c_dev->dev = &pdev->dev;
|
|
|
|
ret = devm_request_threaded_irq(&pdev->dev, irq_event,
|
|
stm32f7_i2c_isr_event,
|
|
stm32f7_i2c_isr_event_thread,
|
|
IRQF_ONESHOT,
|
|
pdev->name, i2c_dev);
|
|
if (ret) {
|
|
dev_err(&pdev->dev, "Failed to request irq event %i\n",
|
|
irq_event);
|
|
goto clk_free;
|
|
}
|
|
|
|
ret = devm_request_irq(&pdev->dev, irq_error, stm32f7_i2c_isr_error, 0,
|
|
pdev->name, i2c_dev);
|
|
if (ret) {
|
|
dev_err(&pdev->dev, "Failed to request irq error %i\n",
|
|
irq_error);
|
|
goto clk_free;
|
|
}
|
|
|
|
setup = of_device_get_match_data(&pdev->dev);
|
|
if (!setup) {
|
|
dev_err(&pdev->dev, "Can't get device data\n");
|
|
ret = -ENODEV;
|
|
goto clk_free;
|
|
}
|
|
i2c_dev->setup = *setup;
|
|
|
|
ret = device_property_read_u32(i2c_dev->dev, "i2c-scl-rising-time-ns",
|
|
&rise_time);
|
|
if (!ret)
|
|
i2c_dev->setup.rise_time = rise_time;
|
|
|
|
ret = device_property_read_u32(i2c_dev->dev, "i2c-scl-falling-time-ns",
|
|
&fall_time);
|
|
if (!ret)
|
|
i2c_dev->setup.fall_time = fall_time;
|
|
|
|
ret = stm32f7_i2c_setup_timing(i2c_dev, &i2c_dev->setup);
|
|
if (ret)
|
|
goto clk_free;
|
|
|
|
adap = &i2c_dev->adap;
|
|
i2c_set_adapdata(adap, i2c_dev);
|
|
snprintf(adap->name, sizeof(adap->name), "STM32F7 I2C(%pa)",
|
|
&res->start);
|
|
adap->owner = THIS_MODULE;
|
|
adap->timeout = 2 * HZ;
|
|
adap->retries = 3;
|
|
adap->algo = &stm32f7_i2c_algo;
|
|
adap->dev.parent = &pdev->dev;
|
|
adap->dev.of_node = pdev->dev.of_node;
|
|
|
|
init_completion(&i2c_dev->complete);
|
|
|
|
/* Init DMA config if supported */
|
|
i2c_dev->dma = stm32_i2c_dma_request(i2c_dev->dev, phy_addr,
|
|
STM32F7_I2C_TXDR,
|
|
STM32F7_I2C_RXDR);
|
|
|
|
platform_set_drvdata(pdev, i2c_dev);
|
|
|
|
pm_runtime_set_autosuspend_delay(i2c_dev->dev,
|
|
STM32F7_AUTOSUSPEND_DELAY);
|
|
pm_runtime_use_autosuspend(i2c_dev->dev);
|
|
pm_runtime_set_active(i2c_dev->dev);
|
|
pm_runtime_enable(i2c_dev->dev);
|
|
|
|
pm_runtime_get_noresume(&pdev->dev);
|
|
|
|
stm32f7_i2c_hw_config(i2c_dev);
|
|
|
|
ret = i2c_add_adapter(adap);
|
|
if (ret)
|
|
goto pm_disable;
|
|
|
|
dev_info(i2c_dev->dev, "STM32F7 I2C-%d bus adapter\n", adap->nr);
|
|
|
|
pm_runtime_mark_last_busy(i2c_dev->dev);
|
|
pm_runtime_put_autosuspend(i2c_dev->dev);
|
|
|
|
return 0;
|
|
|
|
pm_disable:
|
|
pm_runtime_put_noidle(i2c_dev->dev);
|
|
pm_runtime_disable(i2c_dev->dev);
|
|
pm_runtime_set_suspended(i2c_dev->dev);
|
|
pm_runtime_dont_use_autosuspend(i2c_dev->dev);
|
|
|
|
clk_free:
|
|
clk_disable_unprepare(i2c_dev->clk);
|
|
|
|
return ret;
|
|
}
|
|
|
|
static int stm32f7_i2c_remove(struct platform_device *pdev)
|
|
{
|
|
struct stm32f7_i2c_dev *i2c_dev = platform_get_drvdata(pdev);
|
|
|
|
if (i2c_dev->dma) {
|
|
stm32_i2c_dma_free(i2c_dev->dma);
|
|
i2c_dev->dma = NULL;
|
|
}
|
|
|
|
i2c_del_adapter(&i2c_dev->adap);
|
|
pm_runtime_get_sync(i2c_dev->dev);
|
|
|
|
clk_disable_unprepare(i2c_dev->clk);
|
|
|
|
pm_runtime_put_noidle(i2c_dev->dev);
|
|
pm_runtime_disable(i2c_dev->dev);
|
|
pm_runtime_set_suspended(i2c_dev->dev);
|
|
pm_runtime_dont_use_autosuspend(i2c_dev->dev);
|
|
|
|
return 0;
|
|
}
|
|
|
|
#ifdef CONFIG_PM
|
|
static int stm32f7_i2c_runtime_suspend(struct device *dev)
|
|
{
|
|
struct stm32f7_i2c_dev *i2c_dev = dev_get_drvdata(dev);
|
|
|
|
if (!stm32f7_i2c_is_slave_registered(i2c_dev))
|
|
clk_disable_unprepare(i2c_dev->clk);
|
|
|
|
return 0;
|
|
}
|
|
|
|
static int stm32f7_i2c_runtime_resume(struct device *dev)
|
|
{
|
|
struct stm32f7_i2c_dev *i2c_dev = dev_get_drvdata(dev);
|
|
int ret;
|
|
|
|
if (!stm32f7_i2c_is_slave_registered(i2c_dev)) {
|
|
ret = clk_prepare_enable(i2c_dev->clk);
|
|
if (ret) {
|
|
dev_err(dev, "failed to prepare_enable clock\n");
|
|
return ret;
|
|
}
|
|
}
|
|
|
|
return 0;
|
|
}
|
|
#endif
|
|
|
|
static const struct dev_pm_ops stm32f7_i2c_pm_ops = {
|
|
SET_RUNTIME_PM_OPS(stm32f7_i2c_runtime_suspend,
|
|
stm32f7_i2c_runtime_resume, NULL)
|
|
};
|
|
|
|
static const struct of_device_id stm32f7_i2c_match[] = {
|
|
{ .compatible = "st,stm32f7-i2c", .data = &stm32f7_setup},
|
|
{},
|
|
};
|
|
MODULE_DEVICE_TABLE(of, stm32f7_i2c_match);
|
|
|
|
static struct platform_driver stm32f7_i2c_driver = {
|
|
.driver = {
|
|
.name = "stm32f7-i2c",
|
|
.of_match_table = stm32f7_i2c_match,
|
|
.pm = &stm32f7_i2c_pm_ops,
|
|
},
|
|
.probe = stm32f7_i2c_probe,
|
|
.remove = stm32f7_i2c_remove,
|
|
};
|
|
|
|
module_platform_driver(stm32f7_i2c_driver);
|
|
|
|
MODULE_AUTHOR("M'boumba Cedric Madianga <cedric.madianga@gmail.com>");
|
|
MODULE_DESCRIPTION("STMicroelectronics STM32F7 I2C driver");
|
|
MODULE_LICENSE("GPL v2");
|