| Author | Tokens | Token Proportion | Commits | Commit Proportion |
|---|---|---|---|---|
| Pierre-Yves MORDRET | 8739 | 99.82% | 11 | 73.33% |
| Nicolas Le Bayon | 12 | 0.14% | 2 | 13.33% |
| Colin Ian King | 2 | 0.02% | 1 | 6.67% |
| Benjamin Gaignard | 2 | 0.02% | 1 | 6.67% |
| Total | 8755 | 15 |
// SPDX-License-Identifier: GPL-2.0 /* * Driver for STMicroelectronics STM32F7 I2C controller * * This I2C controller is described in the STM32F75xxx and STM32F74xxx Soc * reference manual. * Please see below a link to the documentation: * http://www.st.com/resource/en/reference_manual/dm00124865.pdf * * Copyright (C) M'boumba Cedric Madianga 2017 * Copyright (C) STMicroelectronics 2017 * Author: M'boumba Cedric Madianga <cedric.madianga@gmail.com> * * This driver is based on i2c-stm32f4.c * */ #include <linux/clk.h> #include <linux/delay.h> #include <linux/err.h> #include <linux/i2c.h> #include <linux/interrupt.h> #include <linux/io.h> #include <linux/iopoll.h> #include <linux/mfd/syscon.h> #include <linux/module.h> #include <linux/of.h> #include <linux/of_address.h> #include <linux/of_irq.h> #include <linux/of_platform.h> #include <linux/platform_device.h> #include <linux/pinctrl/consumer.h> #include <linux/pm_runtime.h> #include <linux/regmap.h> #include <linux/reset.h> #include <linux/slab.h> #include "i2c-stm32.h" /* STM32F7 I2C registers */ #define STM32F7_I2C_CR1 0x00 #define STM32F7_I2C_CR2 0x04 #define STM32F7_I2C_OAR1 0x08 #define STM32F7_I2C_OAR2 0x0C #define STM32F7_I2C_PECR 0x20 #define STM32F7_I2C_TIMINGR 0x10 #define STM32F7_I2C_ISR 0x18 #define STM32F7_I2C_ICR 0x1C #define STM32F7_I2C_RXDR 0x24 #define STM32F7_I2C_TXDR 0x28 /* STM32F7 I2C control 1 */ #define STM32F7_I2C_CR1_PECEN BIT(23) #define STM32F7_I2C_CR1_SBC BIT(16) #define STM32F7_I2C_CR1_RXDMAEN BIT(15) #define STM32F7_I2C_CR1_TXDMAEN BIT(14) #define STM32F7_I2C_CR1_ANFOFF BIT(12) #define STM32F7_I2C_CR1_ERRIE BIT(7) #define STM32F7_I2C_CR1_TCIE BIT(6) #define STM32F7_I2C_CR1_STOPIE BIT(5) #define STM32F7_I2C_CR1_NACKIE BIT(4) #define STM32F7_I2C_CR1_ADDRIE BIT(3) #define STM32F7_I2C_CR1_RXIE BIT(2) #define STM32F7_I2C_CR1_TXIE BIT(1) #define STM32F7_I2C_CR1_PE BIT(0) #define STM32F7_I2C_ALL_IRQ_MASK (STM32F7_I2C_CR1_ERRIE \ | STM32F7_I2C_CR1_TCIE \ | STM32F7_I2C_CR1_STOPIE \ | STM32F7_I2C_CR1_NACKIE \ | STM32F7_I2C_CR1_RXIE \ | STM32F7_I2C_CR1_TXIE) #define STM32F7_I2C_XFER_IRQ_MASK (STM32F7_I2C_CR1_TCIE \ | STM32F7_I2C_CR1_STOPIE \ | STM32F7_I2C_CR1_NACKIE \ | STM32F7_I2C_CR1_RXIE \ | STM32F7_I2C_CR1_TXIE) /* STM32F7 I2C control 2 */ #define STM32F7_I2C_CR2_PECBYTE BIT(26) #define STM32F7_I2C_CR2_RELOAD BIT(24) #define STM32F7_I2C_CR2_NBYTES_MASK GENMASK(23, 16) #define STM32F7_I2C_CR2_NBYTES(n) (((n) & 0xff) << 16) #define STM32F7_I2C_CR2_NACK BIT(15) #define STM32F7_I2C_CR2_STOP BIT(14) #define STM32F7_I2C_CR2_START BIT(13) #define STM32F7_I2C_CR2_HEAD10R BIT(12) #define STM32F7_I2C_CR2_ADD10 BIT(11) #define STM32F7_I2C_CR2_RD_WRN BIT(10) #define STM32F7_I2C_CR2_SADD10_MASK GENMASK(9, 0) #define STM32F7_I2C_CR2_SADD10(n) (((n) & \ STM32F7_I2C_CR2_SADD10_MASK)) #define STM32F7_I2C_CR2_SADD7_MASK GENMASK(7, 1) #define STM32F7_I2C_CR2_SADD7(n) (((n) & 0x7f) << 1) /* STM32F7 I2C Own Address 1 */ #define STM32F7_I2C_OAR1_OA1EN BIT(15) #define STM32F7_I2C_OAR1_OA1MODE BIT(10) #define STM32F7_I2C_OAR1_OA1_10_MASK GENMASK(9, 0) #define STM32F7_I2C_OAR1_OA1_10(n) (((n) & \ STM32F7_I2C_OAR1_OA1_10_MASK)) #define STM32F7_I2C_OAR1_OA1_7_MASK GENMASK(7, 1) #define STM32F7_I2C_OAR1_OA1_7(n) (((n) & 0x7f) << 1) #define STM32F7_I2C_OAR1_MASK (STM32F7_I2C_OAR1_OA1_7_MASK \ | STM32F7_I2C_OAR1_OA1_10_MASK \ | STM32F7_I2C_OAR1_OA1EN \ | STM32F7_I2C_OAR1_OA1MODE) /* STM32F7 I2C Own Address 2 */ #define STM32F7_I2C_OAR2_OA2EN BIT(15) #define STM32F7_I2C_OAR2_OA2MSK_MASK GENMASK(10, 8) #define STM32F7_I2C_OAR2_OA2MSK(n) (((n) & 0x7) << 8) #define STM32F7_I2C_OAR2_OA2_7_MASK GENMASK(7, 1) #define STM32F7_I2C_OAR2_OA2_7(n) (((n) & 0x7f) << 1) #define STM32F7_I2C_OAR2_MASK (STM32F7_I2C_OAR2_OA2MSK_MASK \ | STM32F7_I2C_OAR2_OA2_7_MASK \ | STM32F7_I2C_OAR2_OA2EN) /* STM32F7 I2C Interrupt Status */ #define STM32F7_I2C_ISR_ADDCODE_MASK GENMASK(23, 17) #define STM32F7_I2C_ISR_ADDCODE_GET(n) \ (((n) & STM32F7_I2C_ISR_ADDCODE_MASK) >> 17) #define STM32F7_I2C_ISR_DIR BIT(16) #define STM32F7_I2C_ISR_BUSY BIT(15) #define STM32F7_I2C_ISR_PECERR BIT(11) #define STM32F7_I2C_ISR_ARLO BIT(9) #define STM32F7_I2C_ISR_BERR BIT(8) #define STM32F7_I2C_ISR_TCR BIT(7) #define STM32F7_I2C_ISR_TC BIT(6) #define STM32F7_I2C_ISR_STOPF BIT(5) #define STM32F7_I2C_ISR_NACKF BIT(4) #define STM32F7_I2C_ISR_ADDR BIT(3) #define STM32F7_I2C_ISR_RXNE BIT(2) #define STM32F7_I2C_ISR_TXIS BIT(1) #define STM32F7_I2C_ISR_TXE BIT(0) /* STM32F7 I2C Interrupt Clear */ #define STM32F7_I2C_ICR_PECCF BIT(11) #define STM32F7_I2C_ICR_ARLOCF BIT(9) #define STM32F7_I2C_ICR_BERRCF BIT(8) #define STM32F7_I2C_ICR_STOPCF BIT(5) #define STM32F7_I2C_ICR_NACKCF BIT(4) #define STM32F7_I2C_ICR_ADDRCF BIT(3) /* STM32F7 I2C Timing */ #define STM32F7_I2C_TIMINGR_PRESC(n) (((n) & 0xf) << 28) #define STM32F7_I2C_TIMINGR_SCLDEL(n) (((n) & 0xf) << 20) #define STM32F7_I2C_TIMINGR_SDADEL(n) (((n) & 0xf) << 16) #define STM32F7_I2C_TIMINGR_SCLH(n) (((n) & 0xff) << 8) #define STM32F7_I2C_TIMINGR_SCLL(n) ((n) & 0xff) #define STM32F7_I2C_MAX_LEN 0xff #define STM32F7_I2C_DMA_LEN_MIN 0x16 #define STM32F7_I2C_MAX_SLAVE 0x2 #define STM32F7_I2C_DNF_DEFAULT 0 #define STM32F7_I2C_DNF_MAX 16 #define STM32F7_I2C_ANALOG_FILTER_ENABLE 1 #define STM32F7_I2C_ANALOG_FILTER_DELAY_MIN 50 /* ns */ #define STM32F7_I2C_ANALOG_FILTER_DELAY_MAX 260 /* ns */ #define STM32F7_I2C_RISE_TIME_DEFAULT 25 /* ns */ #define STM32F7_I2C_FALL_TIME_DEFAULT 10 /* ns */ #define STM32F7_PRESC_MAX BIT(4) #define STM32F7_SCLDEL_MAX BIT(4) #define STM32F7_SDADEL_MAX BIT(4) #define STM32F7_SCLH_MAX BIT(8) #define STM32F7_SCLL_MAX BIT(8) #define STM32F7_AUTOSUSPEND_DELAY (HZ / 100) /** * struct stm32f7_i2c_spec - private i2c specification timing * @rate: I2C bus speed (Hz) * @rate_min: 80% of I2C bus speed (Hz) * @rate_max: 100% of I2C bus speed (Hz) * @fall_max: Max fall time of both SDA and SCL signals (ns) * @rise_max: Max rise time of both SDA and SCL signals (ns) * @hddat_min: Min data hold time (ns) * @vddat_max: Max data valid time (ns) * @sudat_min: Min data setup time (ns) * @l_min: Min low period of the SCL clock (ns) * @h_min: Min high period of the SCL clock (ns) */ struct stm32f7_i2c_spec { u32 rate; u32 rate_min; u32 rate_max; u32 fall_max; u32 rise_max; u32 hddat_min; u32 vddat_max; u32 sudat_min; u32 l_min; u32 h_min; }; /** * struct stm32f7_i2c_setup - private I2C timing setup parameters * @speed: I2C speed mode (standard, Fast Plus) * @speed_freq: I2C speed frequency (Hz) * @clock_src: I2C clock source frequency (Hz) * @rise_time: Rise time (ns) * @fall_time: Fall time (ns) * @dnf: Digital filter coefficient (0-16) * @analog_filter: Analog filter delay (On/Off) */ struct stm32f7_i2c_setup { enum stm32_i2c_speed speed; u32 speed_freq; u32 clock_src; u32 rise_time; u32 fall_time; u8 dnf; bool analog_filter; }; /** * struct stm32f7_i2c_timings - private I2C output parameters * @node: List entry * @presc: Prescaler value * @scldel: Data setup time * @sdadel: Data hold time * @sclh: SCL high period (master mode) * @scll: SCL low period (master mode) */ struct stm32f7_i2c_timings { struct list_head node; u8 presc; u8 scldel; u8 sdadel; u8 sclh; u8 scll; }; /** * struct stm32f7_i2c_msg - client specific data * @addr: 8-bit or 10-bit slave addr, including r/w bit * @count: number of bytes to be transferred * @buf: data buffer * @result: result of the transfer * @stop: last I2C msg to be sent, i.e. STOP to be generated * @smbus: boolean to know if the I2C IP is used in SMBus mode * @size: type of SMBus protocol * @read_write: direction of SMBus protocol * SMBus block read and SMBus block write - block read process call protocols * @smbus_buf: buffer to be used for SMBus protocol transfer. It will * contain a maximum of 32 bytes of data + byte command + byte count + PEC * This buffer has to be 32-bit aligned to be compliant with memory address * register in DMA mode. */ struct stm32f7_i2c_msg { u16 addr; u32 count; u8 *buf; int result; bool stop; bool smbus; int size; char read_write; u8 smbus_buf[I2C_SMBUS_BLOCK_MAX + 3] __aligned(4); }; /** * struct stm32f7_i2c_dev - private data of the controller * @adap: I2C adapter for this controller * @dev: device for this controller * @base: virtual memory area * @complete: completion of I2C message * @clk: hw i2c clock * @speed: I2C clock frequency of the controller. Standard, Fast or Fast+ * @msg: Pointer to data to be written * @msg_num: number of I2C messages to be executed * @msg_id: message identifiant * @f7_msg: customized i2c msg for driver usage * @setup: I2C timing input setup * @timing: I2C computed timings * @slave: list of slave devices registered on the I2C bus * @slave_running: slave device currently used * @slave_dir: transfer direction for the current slave device * @master_mode: boolean to know in which mode the I2C is running (master or * slave) * @dma: dma data * @use_dma: boolean to know if dma is used in the current transfer * @regmap: holds SYSCFG phandle for Fast Mode Plus bits */ struct stm32f7_i2c_dev { struct i2c_adapter adap; struct device *dev; void __iomem *base; struct completion complete; struct clk *clk; int speed; struct i2c_msg *msg; unsigned int msg_num; unsigned int msg_id; struct stm32f7_i2c_msg f7_msg; struct stm32f7_i2c_setup setup; struct stm32f7_i2c_timings timing; struct i2c_client *slave[STM32F7_I2C_MAX_SLAVE]; struct i2c_client *slave_running; u32 slave_dir; bool master_mode; struct stm32_i2c_dma *dma; bool use_dma; struct regmap *regmap; }; /** * All these values are coming from I2C Specification, Version 6.0, 4th of * April 2014. * * Table10. Characteristics of the SDA and SCL bus lines for Standard, Fast, * and Fast-mode Plus I2C-bus devices */ static struct stm32f7_i2c_spec i2c_specs[] = { [STM32_I2C_SPEED_STANDARD] = { .rate = 100000, .rate_min = 80000, .rate_max = 100000, .fall_max = 300, .rise_max = 1000, .hddat_min = 0, .vddat_max = 3450, .sudat_min = 250, .l_min = 4700, .h_min = 4000, }, [STM32_I2C_SPEED_FAST] = { .rate = 400000, .rate_min = 320000, .rate_max = 400000, .fall_max = 300, .rise_max = 300, .hddat_min = 0, .vddat_max = 900, .sudat_min = 100, .l_min = 1300, .h_min = 600, }, [STM32_I2C_SPEED_FAST_PLUS] = { .rate = 1000000, .rate_min = 800000, .rate_max = 1000000, .fall_max = 100, .rise_max = 120, .hddat_min = 0, .vddat_max = 450, .sudat_min = 50, .l_min = 500, .h_min = 260, }, }; static const struct stm32f7_i2c_setup stm32f7_setup = { .rise_time = STM32F7_I2C_RISE_TIME_DEFAULT, .fall_time = STM32F7_I2C_FALL_TIME_DEFAULT, .dnf = STM32F7_I2C_DNF_DEFAULT, .analog_filter = STM32F7_I2C_ANALOG_FILTER_ENABLE, }; static inline void stm32f7_i2c_set_bits(void __iomem *reg, u32 mask) { writel_relaxed(readl_relaxed(reg) | mask, reg); } static inline void stm32f7_i2c_clr_bits(void __iomem *reg, u32 mask) { writel_relaxed(readl_relaxed(reg) & ~mask, reg); } static void stm32f7_i2c_disable_irq(struct stm32f7_i2c_dev *i2c_dev, u32 mask) { stm32f7_i2c_clr_bits(i2c_dev->base + STM32F7_I2C_CR1, mask); } static int stm32f7_i2c_compute_timing(struct stm32f7_i2c_dev *i2c_dev, struct stm32f7_i2c_setup *setup, struct stm32f7_i2c_timings *output) { u32 p_prev = STM32F7_PRESC_MAX; u32 i2cclk = DIV_ROUND_CLOSEST(NSEC_PER_SEC, setup->clock_src); u32 i2cbus = DIV_ROUND_CLOSEST(NSEC_PER_SEC, setup->speed_freq); u32 clk_error_prev = i2cbus; u32 tsync; u32 af_delay_min, af_delay_max; u32 dnf_delay; u32 clk_min, clk_max; int sdadel_min, sdadel_max; int scldel_min; struct stm32f7_i2c_timings *v, *_v, *s; struct list_head solutions; u16 p, l, a, h; int ret = 0; 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");
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