xref: /openbmc/linux/drivers/i2c/busses/i2c-stm32f7.c (revision e82c878d)
1 // SPDX-License-Identifier: GPL-2.0
2 /*
3  * Driver for STMicroelectronics STM32F7 I2C controller
4  *
5  * This I2C controller is described in the STM32F75xxx and STM32F74xxx Soc
6  * reference manual.
7  * Please see below a link to the documentation:
8  * http://www.st.com/resource/en/reference_manual/dm00124865.pdf
9  *
10  * Copyright (C) M'boumba Cedric Madianga 2017
11  * Copyright (C) STMicroelectronics 2017
12  * Author: M'boumba Cedric Madianga <cedric.madianga@gmail.com>
13  *
14  * This driver is based on i2c-stm32f4.c
15  *
16  */
17 #include <linux/clk.h>
18 #include <linux/delay.h>
19 #include <linux/err.h>
20 #include <linux/i2c.h>
21 #include <linux/interrupt.h>
22 #include <linux/io.h>
23 #include <linux/iopoll.h>
24 #include <linux/mfd/syscon.h>
25 #include <linux/module.h>
26 #include <linux/of.h>
27 #include <linux/of_address.h>
28 #include <linux/of_platform.h>
29 #include <linux/platform_device.h>
30 #include <linux/pinctrl/consumer.h>
31 #include <linux/pm_runtime.h>
32 #include <linux/pm_wakeirq.h>
33 #include <linux/regmap.h>
34 #include <linux/reset.h>
35 #include <linux/slab.h>
36 
37 #include "i2c-stm32.h"
38 
39 /* STM32F7 I2C registers */
40 #define STM32F7_I2C_CR1				0x00
41 #define STM32F7_I2C_CR2				0x04
42 #define STM32F7_I2C_OAR1			0x08
43 #define STM32F7_I2C_OAR2			0x0C
44 #define STM32F7_I2C_PECR			0x20
45 #define STM32F7_I2C_TIMINGR			0x10
46 #define STM32F7_I2C_ISR				0x18
47 #define STM32F7_I2C_ICR				0x1C
48 #define STM32F7_I2C_RXDR			0x24
49 #define STM32F7_I2C_TXDR			0x28
50 
51 /* STM32F7 I2C control 1 */
52 #define STM32F7_I2C_CR1_PECEN			BIT(23)
53 #define STM32F7_I2C_CR1_WUPEN			BIT(18)
54 #define STM32F7_I2C_CR1_SBC			BIT(16)
55 #define STM32F7_I2C_CR1_RXDMAEN			BIT(15)
56 #define STM32F7_I2C_CR1_TXDMAEN			BIT(14)
57 #define STM32F7_I2C_CR1_ANFOFF			BIT(12)
58 #define STM32F7_I2C_CR1_ERRIE			BIT(7)
59 #define STM32F7_I2C_CR1_TCIE			BIT(6)
60 #define STM32F7_I2C_CR1_STOPIE			BIT(5)
61 #define STM32F7_I2C_CR1_NACKIE			BIT(4)
62 #define STM32F7_I2C_CR1_ADDRIE			BIT(3)
63 #define STM32F7_I2C_CR1_RXIE			BIT(2)
64 #define STM32F7_I2C_CR1_TXIE			BIT(1)
65 #define STM32F7_I2C_CR1_PE			BIT(0)
66 #define STM32F7_I2C_ALL_IRQ_MASK		(STM32F7_I2C_CR1_ERRIE \
67 						| STM32F7_I2C_CR1_TCIE \
68 						| STM32F7_I2C_CR1_STOPIE \
69 						| STM32F7_I2C_CR1_NACKIE \
70 						| STM32F7_I2C_CR1_RXIE \
71 						| STM32F7_I2C_CR1_TXIE)
72 #define STM32F7_I2C_XFER_IRQ_MASK		(STM32F7_I2C_CR1_TCIE \
73 						| STM32F7_I2C_CR1_STOPIE \
74 						| STM32F7_I2C_CR1_NACKIE \
75 						| STM32F7_I2C_CR1_RXIE \
76 						| STM32F7_I2C_CR1_TXIE)
77 
78 /* STM32F7 I2C control 2 */
79 #define STM32F7_I2C_CR2_PECBYTE			BIT(26)
80 #define STM32F7_I2C_CR2_RELOAD			BIT(24)
81 #define STM32F7_I2C_CR2_NBYTES_MASK		GENMASK(23, 16)
82 #define STM32F7_I2C_CR2_NBYTES(n)		(((n) & 0xff) << 16)
83 #define STM32F7_I2C_CR2_NACK			BIT(15)
84 #define STM32F7_I2C_CR2_STOP			BIT(14)
85 #define STM32F7_I2C_CR2_START			BIT(13)
86 #define STM32F7_I2C_CR2_HEAD10R			BIT(12)
87 #define STM32F7_I2C_CR2_ADD10			BIT(11)
88 #define STM32F7_I2C_CR2_RD_WRN			BIT(10)
89 #define STM32F7_I2C_CR2_SADD10_MASK		GENMASK(9, 0)
90 #define STM32F7_I2C_CR2_SADD10(n)		(((n) & \
91 						STM32F7_I2C_CR2_SADD10_MASK))
92 #define STM32F7_I2C_CR2_SADD7_MASK		GENMASK(7, 1)
93 #define STM32F7_I2C_CR2_SADD7(n)		(((n) & 0x7f) << 1)
94 
95 /* STM32F7 I2C Own Address 1 */
96 #define STM32F7_I2C_OAR1_OA1EN			BIT(15)
97 #define STM32F7_I2C_OAR1_OA1MODE		BIT(10)
98 #define STM32F7_I2C_OAR1_OA1_10_MASK		GENMASK(9, 0)
99 #define STM32F7_I2C_OAR1_OA1_10(n)		(((n) & \
100 						STM32F7_I2C_OAR1_OA1_10_MASK))
101 #define STM32F7_I2C_OAR1_OA1_7_MASK		GENMASK(7, 1)
102 #define STM32F7_I2C_OAR1_OA1_7(n)		(((n) & 0x7f) << 1)
103 #define STM32F7_I2C_OAR1_MASK			(STM32F7_I2C_OAR1_OA1_7_MASK \
104 						| STM32F7_I2C_OAR1_OA1_10_MASK \
105 						| STM32F7_I2C_OAR1_OA1EN \
106 						| STM32F7_I2C_OAR1_OA1MODE)
107 
108 /* STM32F7 I2C Own Address 2 */
109 #define STM32F7_I2C_OAR2_OA2EN			BIT(15)
110 #define STM32F7_I2C_OAR2_OA2MSK_MASK		GENMASK(10, 8)
111 #define STM32F7_I2C_OAR2_OA2MSK(n)		(((n) & 0x7) << 8)
112 #define STM32F7_I2C_OAR2_OA2_7_MASK		GENMASK(7, 1)
113 #define STM32F7_I2C_OAR2_OA2_7(n)		(((n) & 0x7f) << 1)
114 #define STM32F7_I2C_OAR2_MASK			(STM32F7_I2C_OAR2_OA2MSK_MASK \
115 						| STM32F7_I2C_OAR2_OA2_7_MASK \
116 						| STM32F7_I2C_OAR2_OA2EN)
117 
118 /* STM32F7 I2C Interrupt Status */
119 #define STM32F7_I2C_ISR_ADDCODE_MASK		GENMASK(23, 17)
120 #define STM32F7_I2C_ISR_ADDCODE_GET(n) \
121 				(((n) & STM32F7_I2C_ISR_ADDCODE_MASK) >> 17)
122 #define STM32F7_I2C_ISR_DIR			BIT(16)
123 #define STM32F7_I2C_ISR_BUSY			BIT(15)
124 #define STM32F7_I2C_ISR_PECERR			BIT(11)
125 #define STM32F7_I2C_ISR_ARLO			BIT(9)
126 #define STM32F7_I2C_ISR_BERR			BIT(8)
127 #define STM32F7_I2C_ISR_TCR			BIT(7)
128 #define STM32F7_I2C_ISR_TC			BIT(6)
129 #define STM32F7_I2C_ISR_STOPF			BIT(5)
130 #define STM32F7_I2C_ISR_NACKF			BIT(4)
131 #define STM32F7_I2C_ISR_ADDR			BIT(3)
132 #define STM32F7_I2C_ISR_RXNE			BIT(2)
133 #define STM32F7_I2C_ISR_TXIS			BIT(1)
134 #define STM32F7_I2C_ISR_TXE			BIT(0)
135 
136 /* STM32F7 I2C Interrupt Clear */
137 #define STM32F7_I2C_ICR_PECCF			BIT(11)
138 #define STM32F7_I2C_ICR_ARLOCF			BIT(9)
139 #define STM32F7_I2C_ICR_BERRCF			BIT(8)
140 #define STM32F7_I2C_ICR_STOPCF			BIT(5)
141 #define STM32F7_I2C_ICR_NACKCF			BIT(4)
142 #define STM32F7_I2C_ICR_ADDRCF			BIT(3)
143 
144 /* STM32F7 I2C Timing */
145 #define STM32F7_I2C_TIMINGR_PRESC(n)		(((n) & 0xf) << 28)
146 #define STM32F7_I2C_TIMINGR_SCLDEL(n)		(((n) & 0xf) << 20)
147 #define STM32F7_I2C_TIMINGR_SDADEL(n)		(((n) & 0xf) << 16)
148 #define STM32F7_I2C_TIMINGR_SCLH(n)		(((n) & 0xff) << 8)
149 #define STM32F7_I2C_TIMINGR_SCLL(n)		((n) & 0xff)
150 
151 #define STM32F7_I2C_MAX_LEN			0xff
152 #define STM32F7_I2C_DMA_LEN_MIN			0x16
153 #define STM32F7_I2C_MAX_SLAVE			0x2
154 
155 #define STM32F7_I2C_DNF_DEFAULT			0
156 #define STM32F7_I2C_DNF_MAX			16
157 
158 #define STM32F7_I2C_ANALOG_FILTER_ENABLE	1
159 #define STM32F7_I2C_ANALOG_FILTER_DELAY_MIN	50	/* ns */
160 #define STM32F7_I2C_ANALOG_FILTER_DELAY_MAX	260	/* ns */
161 
162 #define STM32F7_I2C_RISE_TIME_DEFAULT		25	/* ns */
163 #define STM32F7_I2C_FALL_TIME_DEFAULT		10	/* ns */
164 
165 #define STM32F7_PRESC_MAX			BIT(4)
166 #define STM32F7_SCLDEL_MAX			BIT(4)
167 #define STM32F7_SDADEL_MAX			BIT(4)
168 #define STM32F7_SCLH_MAX			BIT(8)
169 #define STM32F7_SCLL_MAX			BIT(8)
170 
171 #define STM32F7_AUTOSUSPEND_DELAY		(HZ / 100)
172 
173 /**
174  * struct stm32f7_i2c_regs - i2c f7 registers backup
175  * @cr1: Control register 1
176  * @cr2: Control register 2
177  * @oar1: Own address 1 register
178  * @oar2: Own address 2 register
179  * @tmgr: Timing register
180  */
181 struct stm32f7_i2c_regs {
182 	u32 cr1;
183 	u32 cr2;
184 	u32 oar1;
185 	u32 oar2;
186 	u32 tmgr;
187 };
188 
189 /**
190  * struct stm32f7_i2c_spec - private i2c specification timing
191  * @rate: I2C bus speed (Hz)
192  * @rate_min: 80% of I2C bus speed (Hz)
193  * @rate_max: 100% of I2C bus speed (Hz)
194  * @fall_max: Max fall time of both SDA and SCL signals (ns)
195  * @rise_max: Max rise time of both SDA and SCL signals (ns)
196  * @hddat_min: Min data hold time (ns)
197  * @vddat_max: Max data valid time (ns)
198  * @sudat_min: Min data setup time (ns)
199  * @l_min: Min low period of the SCL clock (ns)
200  * @h_min: Min high period of the SCL clock (ns)
201  */
202 struct stm32f7_i2c_spec {
203 	u32 rate;
204 	u32 rate_min;
205 	u32 rate_max;
206 	u32 fall_max;
207 	u32 rise_max;
208 	u32 hddat_min;
209 	u32 vddat_max;
210 	u32 sudat_min;
211 	u32 l_min;
212 	u32 h_min;
213 };
214 
215 /**
216  * struct stm32f7_i2c_setup - private I2C timing setup parameters
217  * @speed: I2C speed mode (standard, Fast Plus)
218  * @speed_freq: I2C speed frequency  (Hz)
219  * @clock_src: I2C clock source frequency (Hz)
220  * @rise_time: Rise time (ns)
221  * @fall_time: Fall time (ns)
222  * @dnf: Digital filter coefficient (0-16)
223  * @analog_filter: Analog filter delay (On/Off)
224  * @fmp_clr_offset: Fast Mode Plus clear register offset from set register
225  */
226 struct stm32f7_i2c_setup {
227 	enum stm32_i2c_speed speed;
228 	u32 speed_freq;
229 	u32 clock_src;
230 	u32 rise_time;
231 	u32 fall_time;
232 	u8 dnf;
233 	bool analog_filter;
234 	u32 fmp_clr_offset;
235 };
236 
237 /**
238  * struct stm32f7_i2c_timings - private I2C output parameters
239  * @node: List entry
240  * @presc: Prescaler value
241  * @scldel: Data setup time
242  * @sdadel: Data hold time
243  * @sclh: SCL high period (master mode)
244  * @scll: SCL low period (master mode)
245  */
246 struct stm32f7_i2c_timings {
247 	struct list_head node;
248 	u8 presc;
249 	u8 scldel;
250 	u8 sdadel;
251 	u8 sclh;
252 	u8 scll;
253 };
254 
255 /**
256  * struct stm32f7_i2c_msg - client specific data
257  * @addr: 8-bit or 10-bit slave addr, including r/w bit
258  * @count: number of bytes to be transferred
259  * @buf: data buffer
260  * @result: result of the transfer
261  * @stop: last I2C msg to be sent, i.e. STOP to be generated
262  * @smbus: boolean to know if the I2C IP is used in SMBus mode
263  * @size: type of SMBus protocol
264  * @read_write: direction of SMBus protocol
265  * SMBus block read and SMBus block write - block read process call protocols
266  * @smbus_buf: buffer to be used for SMBus protocol transfer. It will
267  * contain a maximum of 32 bytes of data + byte command + byte count + PEC
268  * This buffer has to be 32-bit aligned to be compliant with memory address
269  * register in DMA mode.
270  */
271 struct stm32f7_i2c_msg {
272 	u16 addr;
273 	u32 count;
274 	u8 *buf;
275 	int result;
276 	bool stop;
277 	bool smbus;
278 	int size;
279 	char read_write;
280 	u8 smbus_buf[I2C_SMBUS_BLOCK_MAX + 3] __aligned(4);
281 };
282 
283 /**
284  * struct stm32f7_i2c_dev - private data of the controller
285  * @adap: I2C adapter for this controller
286  * @dev: device for this controller
287  * @base: virtual memory area
288  * @complete: completion of I2C message
289  * @clk: hw i2c clock
290  * @speed: I2C clock frequency of the controller. Standard, Fast or Fast+
291  * @msg: Pointer to data to be written
292  * @msg_num: number of I2C messages to be executed
293  * @msg_id: message identifiant
294  * @f7_msg: customized i2c msg for driver usage
295  * @setup: I2C timing input setup
296  * @timing: I2C computed timings
297  * @slave: list of slave devices registered on the I2C bus
298  * @slave_running: slave device currently used
299  * @backup_regs: backup of i2c controller registers (for suspend/resume)
300  * @slave_dir: transfer direction for the current slave device
301  * @master_mode: boolean to know in which mode the I2C is running (master or
302  * slave)
303  * @dma: dma data
304  * @use_dma: boolean to know if dma is used in the current transfer
305  * @regmap: holds SYSCFG phandle for Fast Mode Plus bits
306  * @fmp_sreg: register address for setting Fast Mode Plus bits
307  * @fmp_creg: register address for clearing Fast Mode Plus bits
308  * @fmp_mask: mask for Fast Mode Plus bits in set register
309  * @wakeup_src: boolean to know if the device is a wakeup source
310  */
311 struct stm32f7_i2c_dev {
312 	struct i2c_adapter adap;
313 	struct device *dev;
314 	void __iomem *base;
315 	struct completion complete;
316 	struct clk *clk;
317 	int speed;
318 	struct i2c_msg *msg;
319 	unsigned int msg_num;
320 	unsigned int msg_id;
321 	struct stm32f7_i2c_msg f7_msg;
322 	struct stm32f7_i2c_setup setup;
323 	struct stm32f7_i2c_timings timing;
324 	struct i2c_client *slave[STM32F7_I2C_MAX_SLAVE];
325 	struct i2c_client *slave_running;
326 	struct stm32f7_i2c_regs backup_regs;
327 	u32 slave_dir;
328 	bool master_mode;
329 	struct stm32_i2c_dma *dma;
330 	bool use_dma;
331 	struct regmap *regmap;
332 	u32 fmp_sreg;
333 	u32 fmp_creg;
334 	u32 fmp_mask;
335 	bool wakeup_src;
336 };
337 
338 /*
339  * All these values are coming from I2C Specification, Version 6.0, 4th of
340  * April 2014.
341  *
342  * Table10. Characteristics of the SDA and SCL bus lines for Standard, Fast,
343  * and Fast-mode Plus I2C-bus devices
344  */
345 static struct stm32f7_i2c_spec i2c_specs[] = {
346 	[STM32_I2C_SPEED_STANDARD] = {
347 		.rate = I2C_MAX_STANDARD_MODE_FREQ,
348 		.rate_min = I2C_MAX_STANDARD_MODE_FREQ * 8 / 10,	/* 80% */
349 		.rate_max = I2C_MAX_STANDARD_MODE_FREQ,
350 		.fall_max = 300,
351 		.rise_max = 1000,
352 		.hddat_min = 0,
353 		.vddat_max = 3450,
354 		.sudat_min = 250,
355 		.l_min = 4700,
356 		.h_min = 4000,
357 	},
358 	[STM32_I2C_SPEED_FAST] = {
359 		.rate = I2C_MAX_FAST_MODE_FREQ,
360 		.rate_min = I2C_MAX_FAST_MODE_FREQ * 8 / 10,		/* 80% */
361 		.rate_max = I2C_MAX_FAST_MODE_FREQ,
362 		.fall_max = 300,
363 		.rise_max = 300,
364 		.hddat_min = 0,
365 		.vddat_max = 900,
366 		.sudat_min = 100,
367 		.l_min = 1300,
368 		.h_min = 600,
369 	},
370 	[STM32_I2C_SPEED_FAST_PLUS] = {
371 		.rate = I2C_MAX_FAST_MODE_PLUS_FREQ,
372 		.rate_min = I2C_MAX_FAST_MODE_PLUS_FREQ * 8 / 10,	/* 80% */
373 		.rate_max = I2C_MAX_FAST_MODE_PLUS_FREQ,
374 		.fall_max = 100,
375 		.rise_max = 120,
376 		.hddat_min = 0,
377 		.vddat_max = 450,
378 		.sudat_min = 50,
379 		.l_min = 500,
380 		.h_min = 260,
381 	},
382 };
383 
384 static const struct stm32f7_i2c_setup stm32f7_setup = {
385 	.rise_time = STM32F7_I2C_RISE_TIME_DEFAULT,
386 	.fall_time = STM32F7_I2C_FALL_TIME_DEFAULT,
387 	.dnf = STM32F7_I2C_DNF_DEFAULT,
388 	.analog_filter = STM32F7_I2C_ANALOG_FILTER_ENABLE,
389 };
390 
391 static const struct stm32f7_i2c_setup stm32mp15_setup = {
392 	.rise_time = STM32F7_I2C_RISE_TIME_DEFAULT,
393 	.fall_time = STM32F7_I2C_FALL_TIME_DEFAULT,
394 	.dnf = STM32F7_I2C_DNF_DEFAULT,
395 	.analog_filter = STM32F7_I2C_ANALOG_FILTER_ENABLE,
396 	.fmp_clr_offset = 0x40,
397 };
398 
399 static inline void stm32f7_i2c_set_bits(void __iomem *reg, u32 mask)
400 {
401 	writel_relaxed(readl_relaxed(reg) | mask, reg);
402 }
403 
404 static inline void stm32f7_i2c_clr_bits(void __iomem *reg, u32 mask)
405 {
406 	writel_relaxed(readl_relaxed(reg) & ~mask, reg);
407 }
408 
409 static void stm32f7_i2c_disable_irq(struct stm32f7_i2c_dev *i2c_dev, u32 mask)
410 {
411 	stm32f7_i2c_clr_bits(i2c_dev->base + STM32F7_I2C_CR1, mask);
412 }
413 
414 static int stm32f7_i2c_compute_timing(struct stm32f7_i2c_dev *i2c_dev,
415 				      struct stm32f7_i2c_setup *setup,
416 				      struct stm32f7_i2c_timings *output)
417 {
418 	u32 p_prev = STM32F7_PRESC_MAX;
419 	u32 i2cclk = DIV_ROUND_CLOSEST(NSEC_PER_SEC,
420 				       setup->clock_src);
421 	u32 i2cbus = DIV_ROUND_CLOSEST(NSEC_PER_SEC,
422 				       setup->speed_freq);
423 	u32 clk_error_prev = i2cbus;
424 	u32 tsync;
425 	u32 af_delay_min, af_delay_max;
426 	u32 dnf_delay;
427 	u32 clk_min, clk_max;
428 	int sdadel_min, sdadel_max;
429 	int scldel_min;
430 	struct stm32f7_i2c_timings *v, *_v, *s;
431 	struct list_head solutions;
432 	u16 p, l, a, h;
433 	int ret = 0;
434 
435 	if (setup->speed >= STM32_I2C_SPEED_END) {
436 		dev_err(i2c_dev->dev, "speed out of bound {%d/%d}\n",
437 			setup->speed, STM32_I2C_SPEED_END - 1);
438 		return -EINVAL;
439 	}
440 
441 	if ((setup->rise_time > i2c_specs[setup->speed].rise_max) ||
442 	    (setup->fall_time > i2c_specs[setup->speed].fall_max)) {
443 		dev_err(i2c_dev->dev,
444 			"timings out of bound Rise{%d>%d}/Fall{%d>%d}\n",
445 			setup->rise_time, i2c_specs[setup->speed].rise_max,
446 			setup->fall_time, i2c_specs[setup->speed].fall_max);
447 		return -EINVAL;
448 	}
449 
450 	if (setup->dnf > STM32F7_I2C_DNF_MAX) {
451 		dev_err(i2c_dev->dev,
452 			"DNF out of bound %d/%d\n",
453 			setup->dnf, STM32F7_I2C_DNF_MAX);
454 		return -EINVAL;
455 	}
456 
457 	if (setup->speed_freq > i2c_specs[setup->speed].rate) {
458 		dev_err(i2c_dev->dev, "ERROR: Freq {%d/%d}\n",
459 			setup->speed_freq, i2c_specs[setup->speed].rate);
460 		return -EINVAL;
461 	}
462 
463 	/*  Analog and Digital Filters */
464 	af_delay_min =
465 		(setup->analog_filter ?
466 		 STM32F7_I2C_ANALOG_FILTER_DELAY_MIN : 0);
467 	af_delay_max =
468 		(setup->analog_filter ?
469 		 STM32F7_I2C_ANALOG_FILTER_DELAY_MAX : 0);
470 	dnf_delay = setup->dnf * i2cclk;
471 
472 	sdadel_min = i2c_specs[setup->speed].hddat_min + setup->fall_time -
473 		af_delay_min - (setup->dnf + 3) * i2cclk;
474 
475 	sdadel_max = i2c_specs[setup->speed].vddat_max - setup->rise_time -
476 		af_delay_max - (setup->dnf + 4) * i2cclk;
477 
478 	scldel_min = setup->rise_time + i2c_specs[setup->speed].sudat_min;
479 
480 	if (sdadel_min < 0)
481 		sdadel_min = 0;
482 	if (sdadel_max < 0)
483 		sdadel_max = 0;
484 
485 	dev_dbg(i2c_dev->dev, "SDADEL(min/max): %i/%i, SCLDEL(Min): %i\n",
486 		sdadel_min, sdadel_max, scldel_min);
487 
488 	INIT_LIST_HEAD(&solutions);
489 	/* Compute possible values for PRESC, SCLDEL and SDADEL */
490 	for (p = 0; p < STM32F7_PRESC_MAX; p++) {
491 		for (l = 0; l < STM32F7_SCLDEL_MAX; l++) {
492 			u32 scldel = (l + 1) * (p + 1) * i2cclk;
493 
494 			if (scldel < scldel_min)
495 				continue;
496 
497 			for (a = 0; a < STM32F7_SDADEL_MAX; a++) {
498 				u32 sdadel = (a * (p + 1) + 1) * i2cclk;
499 
500 				if (((sdadel >= sdadel_min) &&
501 				     (sdadel <= sdadel_max)) &&
502 				    (p != p_prev)) {
503 					v = kmalloc(sizeof(*v), GFP_KERNEL);
504 					if (!v) {
505 						ret = -ENOMEM;
506 						goto exit;
507 					}
508 
509 					v->presc = p;
510 					v->scldel = l;
511 					v->sdadel = a;
512 					p_prev = p;
513 
514 					list_add_tail(&v->node,
515 						      &solutions);
516 					break;
517 				}
518 			}
519 
520 			if (p_prev == p)
521 				break;
522 		}
523 	}
524 
525 	if (list_empty(&solutions)) {
526 		dev_err(i2c_dev->dev, "no Prescaler solution\n");
527 		ret = -EPERM;
528 		goto exit;
529 	}
530 
531 	tsync = af_delay_min + dnf_delay + (2 * i2cclk);
532 	s = NULL;
533 	clk_max = NSEC_PER_SEC / i2c_specs[setup->speed].rate_min;
534 	clk_min = NSEC_PER_SEC / i2c_specs[setup->speed].rate_max;
535 
536 	/*
537 	 * Among Prescaler possibilities discovered above figures out SCL Low
538 	 * and High Period. Provided:
539 	 * - SCL Low Period has to be higher than SCL Clock Low Period
540 	 *   defined by I2C Specification. I2C Clock has to be lower than
541 	 *   (SCL Low Period - Analog/Digital filters) / 4.
542 	 * - SCL High Period has to be lower than SCL Clock High Period
543 	 *   defined by I2C Specification
544 	 * - I2C Clock has to be lower than SCL High Period
545 	 */
546 	list_for_each_entry(v, &solutions, node) {
547 		u32 prescaler = (v->presc + 1) * i2cclk;
548 
549 		for (l = 0; l < STM32F7_SCLL_MAX; l++) {
550 			u32 tscl_l = (l + 1) * prescaler + tsync;
551 
552 			if ((tscl_l < i2c_specs[setup->speed].l_min) ||
553 			    (i2cclk >=
554 			     ((tscl_l - af_delay_min - dnf_delay) / 4))) {
555 				continue;
556 			}
557 
558 			for (h = 0; h < STM32F7_SCLH_MAX; h++) {
559 				u32 tscl_h = (h + 1) * prescaler + tsync;
560 				u32 tscl = tscl_l + tscl_h +
561 					setup->rise_time + setup->fall_time;
562 
563 				if ((tscl >= clk_min) && (tscl <= clk_max) &&
564 				    (tscl_h >= i2c_specs[setup->speed].h_min) &&
565 				    (i2cclk < tscl_h)) {
566 					int clk_error = tscl - i2cbus;
567 
568 					if (clk_error < 0)
569 						clk_error = -clk_error;
570 
571 					if (clk_error < clk_error_prev) {
572 						clk_error_prev = clk_error;
573 						v->scll = l;
574 						v->sclh = h;
575 						s = v;
576 					}
577 				}
578 			}
579 		}
580 	}
581 
582 	if (!s) {
583 		dev_err(i2c_dev->dev, "no solution at all\n");
584 		ret = -EPERM;
585 		goto exit;
586 	}
587 
588 	output->presc = s->presc;
589 	output->scldel = s->scldel;
590 	output->sdadel = s->sdadel;
591 	output->scll = s->scll;
592 	output->sclh = s->sclh;
593 
594 	dev_dbg(i2c_dev->dev,
595 		"Presc: %i, scldel: %i, sdadel: %i, scll: %i, sclh: %i\n",
596 		output->presc,
597 		output->scldel, output->sdadel,
598 		output->scll, output->sclh);
599 
600 exit:
601 	/* Release list and memory */
602 	list_for_each_entry_safe(v, _v, &solutions, node) {
603 		list_del(&v->node);
604 		kfree(v);
605 	}
606 
607 	return ret;
608 }
609 
610 static int stm32f7_i2c_setup_timing(struct stm32f7_i2c_dev *i2c_dev,
611 				    struct stm32f7_i2c_setup *setup)
612 {
613 	struct i2c_timings timings, *t = &timings;
614 	int ret = 0;
615 
616 	t->bus_freq_hz = I2C_MAX_STANDARD_MODE_FREQ;
617 	t->scl_rise_ns = i2c_dev->setup.rise_time;
618 	t->scl_fall_ns = i2c_dev->setup.fall_time;
619 
620 	i2c_parse_fw_timings(i2c_dev->dev, t, false);
621 
622 	if (t->bus_freq_hz >= I2C_MAX_FAST_MODE_PLUS_FREQ)
623 		i2c_dev->speed = STM32_I2C_SPEED_FAST_PLUS;
624 	else if (t->bus_freq_hz >= I2C_MAX_FAST_MODE_FREQ)
625 		i2c_dev->speed = STM32_I2C_SPEED_FAST;
626 	else
627 		i2c_dev->speed = STM32_I2C_SPEED_STANDARD;
628 
629 	i2c_dev->setup.rise_time = t->scl_rise_ns;
630 	i2c_dev->setup.fall_time = t->scl_fall_ns;
631 
632 	setup->speed = i2c_dev->speed;
633 	setup->speed_freq = i2c_specs[setup->speed].rate;
634 	setup->clock_src = clk_get_rate(i2c_dev->clk);
635 
636 	if (!setup->clock_src) {
637 		dev_err(i2c_dev->dev, "clock rate is 0\n");
638 		return -EINVAL;
639 	}
640 
641 	do {
642 		ret = stm32f7_i2c_compute_timing(i2c_dev, setup,
643 						 &i2c_dev->timing);
644 		if (ret) {
645 			dev_err(i2c_dev->dev,
646 				"failed to compute I2C timings.\n");
647 			if (i2c_dev->speed > STM32_I2C_SPEED_STANDARD) {
648 				i2c_dev->speed--;
649 				setup->speed = i2c_dev->speed;
650 				setup->speed_freq =
651 					i2c_specs[setup->speed].rate;
652 				dev_warn(i2c_dev->dev,
653 					 "downgrade I2C Speed Freq to (%i)\n",
654 					 i2c_specs[setup->speed].rate);
655 			} else {
656 				break;
657 			}
658 		}
659 	} while (ret);
660 
661 	if (ret) {
662 		dev_err(i2c_dev->dev, "Impossible to compute I2C timings.\n");
663 		return ret;
664 	}
665 
666 	dev_dbg(i2c_dev->dev, "I2C Speed(%i), Freq(%i), Clk Source(%i)\n",
667 		setup->speed, setup->speed_freq, setup->clock_src);
668 	dev_dbg(i2c_dev->dev, "I2C Rise(%i) and Fall(%i) Time\n",
669 		setup->rise_time, setup->fall_time);
670 	dev_dbg(i2c_dev->dev, "I2C Analog Filter(%s), DNF(%i)\n",
671 		(setup->analog_filter ? "On" : "Off"), setup->dnf);
672 
673 	return 0;
674 }
675 
676 static void stm32f7_i2c_disable_dma_req(struct stm32f7_i2c_dev *i2c_dev)
677 {
678 	void __iomem *base = i2c_dev->base;
679 	u32 mask = STM32F7_I2C_CR1_RXDMAEN | STM32F7_I2C_CR1_TXDMAEN;
680 
681 	stm32f7_i2c_clr_bits(base + STM32F7_I2C_CR1, mask);
682 }
683 
684 static void stm32f7_i2c_dma_callback(void *arg)
685 {
686 	struct stm32f7_i2c_dev *i2c_dev = (struct stm32f7_i2c_dev *)arg;
687 	struct stm32_i2c_dma *dma = i2c_dev->dma;
688 	struct device *dev = dma->chan_using->device->dev;
689 
690 	stm32f7_i2c_disable_dma_req(i2c_dev);
691 	dma_unmap_single(dev, dma->dma_buf, dma->dma_len, dma->dma_data_dir);
692 	complete(&dma->dma_complete);
693 }
694 
695 static void stm32f7_i2c_hw_config(struct stm32f7_i2c_dev *i2c_dev)
696 {
697 	struct stm32f7_i2c_timings *t = &i2c_dev->timing;
698 	u32 timing = 0;
699 
700 	/* Timing settings */
701 	timing |= STM32F7_I2C_TIMINGR_PRESC(t->presc);
702 	timing |= STM32F7_I2C_TIMINGR_SCLDEL(t->scldel);
703 	timing |= STM32F7_I2C_TIMINGR_SDADEL(t->sdadel);
704 	timing |= STM32F7_I2C_TIMINGR_SCLH(t->sclh);
705 	timing |= STM32F7_I2C_TIMINGR_SCLL(t->scll);
706 	writel_relaxed(timing, i2c_dev->base + STM32F7_I2C_TIMINGR);
707 
708 	/* Enable I2C */
709 	if (i2c_dev->setup.analog_filter)
710 		stm32f7_i2c_clr_bits(i2c_dev->base + STM32F7_I2C_CR1,
711 				     STM32F7_I2C_CR1_ANFOFF);
712 	else
713 		stm32f7_i2c_set_bits(i2c_dev->base + STM32F7_I2C_CR1,
714 				     STM32F7_I2C_CR1_ANFOFF);
715 	stm32f7_i2c_set_bits(i2c_dev->base + STM32F7_I2C_CR1,
716 			     STM32F7_I2C_CR1_PE);
717 }
718 
719 static void stm32f7_i2c_write_tx_data(struct stm32f7_i2c_dev *i2c_dev)
720 {
721 	struct stm32f7_i2c_msg *f7_msg = &i2c_dev->f7_msg;
722 	void __iomem *base = i2c_dev->base;
723 
724 	if (f7_msg->count) {
725 		writeb_relaxed(*f7_msg->buf++, base + STM32F7_I2C_TXDR);
726 		f7_msg->count--;
727 	}
728 }
729 
730 static void stm32f7_i2c_read_rx_data(struct stm32f7_i2c_dev *i2c_dev)
731 {
732 	struct stm32f7_i2c_msg *f7_msg = &i2c_dev->f7_msg;
733 	void __iomem *base = i2c_dev->base;
734 
735 	if (f7_msg->count) {
736 		*f7_msg->buf++ = readb_relaxed(base + STM32F7_I2C_RXDR);
737 		f7_msg->count--;
738 	} else {
739 		/* Flush RX buffer has no data is expected */
740 		readb_relaxed(base + STM32F7_I2C_RXDR);
741 	}
742 }
743 
744 static void stm32f7_i2c_reload(struct stm32f7_i2c_dev *i2c_dev)
745 {
746 	struct stm32f7_i2c_msg *f7_msg = &i2c_dev->f7_msg;
747 	u32 cr2;
748 
749 	if (i2c_dev->use_dma)
750 		f7_msg->count -= STM32F7_I2C_MAX_LEN;
751 
752 	cr2 = readl_relaxed(i2c_dev->base + STM32F7_I2C_CR2);
753 
754 	cr2 &= ~STM32F7_I2C_CR2_NBYTES_MASK;
755 	if (f7_msg->count > STM32F7_I2C_MAX_LEN) {
756 		cr2 |= STM32F7_I2C_CR2_NBYTES(STM32F7_I2C_MAX_LEN);
757 	} else {
758 		cr2 &= ~STM32F7_I2C_CR2_RELOAD;
759 		cr2 |= STM32F7_I2C_CR2_NBYTES(f7_msg->count);
760 	}
761 
762 	writel_relaxed(cr2, i2c_dev->base + STM32F7_I2C_CR2);
763 }
764 
765 static void stm32f7_i2c_smbus_reload(struct stm32f7_i2c_dev *i2c_dev)
766 {
767 	struct stm32f7_i2c_msg *f7_msg = &i2c_dev->f7_msg;
768 	u32 cr2;
769 	u8 *val;
770 
771 	/*
772 	 * For I2C_SMBUS_BLOCK_DATA && I2C_SMBUS_BLOCK_PROC_CALL, the first
773 	 * data received inform us how many data will follow.
774 	 */
775 	stm32f7_i2c_read_rx_data(i2c_dev);
776 
777 	/*
778 	 * Update NBYTES with the value read to continue the transfer
779 	 */
780 	val = f7_msg->buf - sizeof(u8);
781 	f7_msg->count = *val;
782 	cr2 = readl_relaxed(i2c_dev->base + STM32F7_I2C_CR2);
783 	cr2 &= ~(STM32F7_I2C_CR2_NBYTES_MASK | STM32F7_I2C_CR2_RELOAD);
784 	cr2 |= STM32F7_I2C_CR2_NBYTES(f7_msg->count);
785 	writel_relaxed(cr2, i2c_dev->base + STM32F7_I2C_CR2);
786 }
787 
788 static int stm32f7_i2c_release_bus(struct i2c_adapter *i2c_adap)
789 {
790 	struct stm32f7_i2c_dev *i2c_dev = i2c_get_adapdata(i2c_adap);
791 
792 	dev_info(i2c_dev->dev, "Trying to recover bus\n");
793 
794 	stm32f7_i2c_clr_bits(i2c_dev->base + STM32F7_I2C_CR1,
795 			     STM32F7_I2C_CR1_PE);
796 
797 	stm32f7_i2c_hw_config(i2c_dev);
798 
799 	return 0;
800 }
801 
802 static int stm32f7_i2c_wait_free_bus(struct stm32f7_i2c_dev *i2c_dev)
803 {
804 	u32 status;
805 	int ret;
806 
807 	ret = readl_relaxed_poll_timeout(i2c_dev->base + STM32F7_I2C_ISR,
808 					 status,
809 					 !(status & STM32F7_I2C_ISR_BUSY),
810 					 10, 1000);
811 	if (!ret)
812 		return 0;
813 
814 	dev_info(i2c_dev->dev, "bus busy\n");
815 
816 	ret = stm32f7_i2c_release_bus(&i2c_dev->adap);
817 	if (ret) {
818 		dev_err(i2c_dev->dev, "Failed to recover the bus (%d)\n", ret);
819 		return ret;
820 	}
821 
822 	return -EBUSY;
823 }
824 
825 static void stm32f7_i2c_xfer_msg(struct stm32f7_i2c_dev *i2c_dev,
826 				 struct i2c_msg *msg)
827 {
828 	struct stm32f7_i2c_msg *f7_msg = &i2c_dev->f7_msg;
829 	void __iomem *base = i2c_dev->base;
830 	u32 cr1, cr2;
831 	int ret;
832 
833 	f7_msg->addr = msg->addr;
834 	f7_msg->buf = msg->buf;
835 	f7_msg->count = msg->len;
836 	f7_msg->result = 0;
837 	f7_msg->stop = (i2c_dev->msg_id >= i2c_dev->msg_num - 1);
838 
839 	reinit_completion(&i2c_dev->complete);
840 
841 	cr1 = readl_relaxed(base + STM32F7_I2C_CR1);
842 	cr2 = readl_relaxed(base + STM32F7_I2C_CR2);
843 
844 	/* Set transfer direction */
845 	cr2 &= ~STM32F7_I2C_CR2_RD_WRN;
846 	if (msg->flags & I2C_M_RD)
847 		cr2 |= STM32F7_I2C_CR2_RD_WRN;
848 
849 	/* Set slave address */
850 	cr2 &= ~(STM32F7_I2C_CR2_HEAD10R | STM32F7_I2C_CR2_ADD10);
851 	if (msg->flags & I2C_M_TEN) {
852 		cr2 &= ~STM32F7_I2C_CR2_SADD10_MASK;
853 		cr2 |= STM32F7_I2C_CR2_SADD10(f7_msg->addr);
854 		cr2 |= STM32F7_I2C_CR2_ADD10;
855 	} else {
856 		cr2 &= ~STM32F7_I2C_CR2_SADD7_MASK;
857 		cr2 |= STM32F7_I2C_CR2_SADD7(f7_msg->addr);
858 	}
859 
860 	/* Set nb bytes to transfer and reload if needed */
861 	cr2 &= ~(STM32F7_I2C_CR2_NBYTES_MASK | STM32F7_I2C_CR2_RELOAD);
862 	if (f7_msg->count > STM32F7_I2C_MAX_LEN) {
863 		cr2 |= STM32F7_I2C_CR2_NBYTES(STM32F7_I2C_MAX_LEN);
864 		cr2 |= STM32F7_I2C_CR2_RELOAD;
865 	} else {
866 		cr2 |= STM32F7_I2C_CR2_NBYTES(f7_msg->count);
867 	}
868 
869 	/* Enable NACK, STOP, error and transfer complete interrupts */
870 	cr1 |= STM32F7_I2C_CR1_ERRIE | STM32F7_I2C_CR1_TCIE |
871 		STM32F7_I2C_CR1_STOPIE | STM32F7_I2C_CR1_NACKIE;
872 
873 	/* Clear DMA req and TX/RX interrupt */
874 	cr1 &= ~(STM32F7_I2C_CR1_RXIE | STM32F7_I2C_CR1_TXIE |
875 			STM32F7_I2C_CR1_RXDMAEN | STM32F7_I2C_CR1_TXDMAEN);
876 
877 	/* Configure DMA or enable RX/TX interrupt */
878 	i2c_dev->use_dma = false;
879 	if (i2c_dev->dma && f7_msg->count >= STM32F7_I2C_DMA_LEN_MIN) {
880 		ret = stm32_i2c_prep_dma_xfer(i2c_dev->dev, i2c_dev->dma,
881 					      msg->flags & I2C_M_RD,
882 					      f7_msg->count, f7_msg->buf,
883 					      stm32f7_i2c_dma_callback,
884 					      i2c_dev);
885 		if (!ret)
886 			i2c_dev->use_dma = true;
887 		else
888 			dev_warn(i2c_dev->dev, "can't use DMA\n");
889 	}
890 
891 	if (!i2c_dev->use_dma) {
892 		if (msg->flags & I2C_M_RD)
893 			cr1 |= STM32F7_I2C_CR1_RXIE;
894 		else
895 			cr1 |= STM32F7_I2C_CR1_TXIE;
896 	} else {
897 		if (msg->flags & I2C_M_RD)
898 			cr1 |= STM32F7_I2C_CR1_RXDMAEN;
899 		else
900 			cr1 |= STM32F7_I2C_CR1_TXDMAEN;
901 	}
902 
903 	/* Configure Start/Repeated Start */
904 	cr2 |= STM32F7_I2C_CR2_START;
905 
906 	i2c_dev->master_mode = true;
907 
908 	/* Write configurations registers */
909 	writel_relaxed(cr1, base + STM32F7_I2C_CR1);
910 	writel_relaxed(cr2, base + STM32F7_I2C_CR2);
911 }
912 
913 static int stm32f7_i2c_smbus_xfer_msg(struct stm32f7_i2c_dev *i2c_dev,
914 				      unsigned short flags, u8 command,
915 				      union i2c_smbus_data *data)
916 {
917 	struct stm32f7_i2c_msg *f7_msg = &i2c_dev->f7_msg;
918 	struct device *dev = i2c_dev->dev;
919 	void __iomem *base = i2c_dev->base;
920 	u32 cr1, cr2;
921 	int i, ret;
922 
923 	f7_msg->result = 0;
924 	reinit_completion(&i2c_dev->complete);
925 
926 	cr2 = readl_relaxed(base + STM32F7_I2C_CR2);
927 	cr1 = readl_relaxed(base + STM32F7_I2C_CR1);
928 
929 	/* Set transfer direction */
930 	cr2 &= ~STM32F7_I2C_CR2_RD_WRN;
931 	if (f7_msg->read_write)
932 		cr2 |= STM32F7_I2C_CR2_RD_WRN;
933 
934 	/* Set slave address */
935 	cr2 &= ~(STM32F7_I2C_CR2_ADD10 | STM32F7_I2C_CR2_SADD7_MASK);
936 	cr2 |= STM32F7_I2C_CR2_SADD7(f7_msg->addr);
937 
938 	f7_msg->smbus_buf[0] = command;
939 	switch (f7_msg->size) {
940 	case I2C_SMBUS_QUICK:
941 		f7_msg->stop = true;
942 		f7_msg->count = 0;
943 		break;
944 	case I2C_SMBUS_BYTE:
945 		f7_msg->stop = true;
946 		f7_msg->count = 1;
947 		break;
948 	case I2C_SMBUS_BYTE_DATA:
949 		if (f7_msg->read_write) {
950 			f7_msg->stop = false;
951 			f7_msg->count = 1;
952 			cr2 &= ~STM32F7_I2C_CR2_RD_WRN;
953 		} else {
954 			f7_msg->stop = true;
955 			f7_msg->count = 2;
956 			f7_msg->smbus_buf[1] = data->byte;
957 		}
958 		break;
959 	case I2C_SMBUS_WORD_DATA:
960 		if (f7_msg->read_write) {
961 			f7_msg->stop = false;
962 			f7_msg->count = 1;
963 			cr2 &= ~STM32F7_I2C_CR2_RD_WRN;
964 		} else {
965 			f7_msg->stop = true;
966 			f7_msg->count = 3;
967 			f7_msg->smbus_buf[1] = data->word & 0xff;
968 			f7_msg->smbus_buf[2] = data->word >> 8;
969 		}
970 		break;
971 	case I2C_SMBUS_BLOCK_DATA:
972 		if (f7_msg->read_write) {
973 			f7_msg->stop = false;
974 			f7_msg->count = 1;
975 			cr2 &= ~STM32F7_I2C_CR2_RD_WRN;
976 		} else {
977 			f7_msg->stop = true;
978 			if (data->block[0] > I2C_SMBUS_BLOCK_MAX ||
979 			    !data->block[0]) {
980 				dev_err(dev, "Invalid block write size %d\n",
981 					data->block[0]);
982 				return -EINVAL;
983 			}
984 			f7_msg->count = data->block[0] + 2;
985 			for (i = 1; i < f7_msg->count; i++)
986 				f7_msg->smbus_buf[i] = data->block[i - 1];
987 		}
988 		break;
989 	case I2C_SMBUS_PROC_CALL:
990 		f7_msg->stop = false;
991 		f7_msg->count = 3;
992 		f7_msg->smbus_buf[1] = data->word & 0xff;
993 		f7_msg->smbus_buf[2] = data->word >> 8;
994 		cr2 &= ~STM32F7_I2C_CR2_RD_WRN;
995 		f7_msg->read_write = I2C_SMBUS_READ;
996 		break;
997 	case I2C_SMBUS_BLOCK_PROC_CALL:
998 		f7_msg->stop = false;
999 		if (data->block[0] > I2C_SMBUS_BLOCK_MAX - 1) {
1000 			dev_err(dev, "Invalid block write size %d\n",
1001 				data->block[0]);
1002 			return -EINVAL;
1003 		}
1004 		f7_msg->count = data->block[0] + 2;
1005 		for (i = 1; i < f7_msg->count; i++)
1006 			f7_msg->smbus_buf[i] = data->block[i - 1];
1007 		cr2 &= ~STM32F7_I2C_CR2_RD_WRN;
1008 		f7_msg->read_write = I2C_SMBUS_READ;
1009 		break;
1010 	case I2C_SMBUS_I2C_BLOCK_DATA:
1011 		/* Rely on emulated i2c transfer (through master_xfer) */
1012 		return -EOPNOTSUPP;
1013 	default:
1014 		dev_err(dev, "Unsupported smbus protocol %d\n", f7_msg->size);
1015 		return -EOPNOTSUPP;
1016 	}
1017 
1018 	f7_msg->buf = f7_msg->smbus_buf;
1019 
1020 	/* Configure PEC */
1021 	if ((flags & I2C_CLIENT_PEC) && f7_msg->size != I2C_SMBUS_QUICK) {
1022 		cr1 |= STM32F7_I2C_CR1_PECEN;
1023 		cr2 |= STM32F7_I2C_CR2_PECBYTE;
1024 		if (!f7_msg->read_write)
1025 			f7_msg->count++;
1026 	} else {
1027 		cr1 &= ~STM32F7_I2C_CR1_PECEN;
1028 		cr2 &= ~STM32F7_I2C_CR2_PECBYTE;
1029 	}
1030 
1031 	/* Set number of bytes to be transferred */
1032 	cr2 &= ~(STM32F7_I2C_CR2_NBYTES_MASK | STM32F7_I2C_CR2_RELOAD);
1033 	cr2 |= STM32F7_I2C_CR2_NBYTES(f7_msg->count);
1034 
1035 	/* Enable NACK, STOP, error and transfer complete interrupts */
1036 	cr1 |= STM32F7_I2C_CR1_ERRIE | STM32F7_I2C_CR1_TCIE |
1037 		STM32F7_I2C_CR1_STOPIE | STM32F7_I2C_CR1_NACKIE;
1038 
1039 	/* Clear DMA req and TX/RX interrupt */
1040 	cr1 &= ~(STM32F7_I2C_CR1_RXIE | STM32F7_I2C_CR1_TXIE |
1041 			STM32F7_I2C_CR1_RXDMAEN | STM32F7_I2C_CR1_TXDMAEN);
1042 
1043 	/* Configure DMA or enable RX/TX interrupt */
1044 	i2c_dev->use_dma = false;
1045 	if (i2c_dev->dma && f7_msg->count >= STM32F7_I2C_DMA_LEN_MIN) {
1046 		ret = stm32_i2c_prep_dma_xfer(i2c_dev->dev, i2c_dev->dma,
1047 					      cr2 & STM32F7_I2C_CR2_RD_WRN,
1048 					      f7_msg->count, f7_msg->buf,
1049 					      stm32f7_i2c_dma_callback,
1050 					      i2c_dev);
1051 		if (!ret)
1052 			i2c_dev->use_dma = true;
1053 		else
1054 			dev_warn(i2c_dev->dev, "can't use DMA\n");
1055 	}
1056 
1057 	if (!i2c_dev->use_dma) {
1058 		if (cr2 & STM32F7_I2C_CR2_RD_WRN)
1059 			cr1 |= STM32F7_I2C_CR1_RXIE;
1060 		else
1061 			cr1 |= STM32F7_I2C_CR1_TXIE;
1062 	} else {
1063 		if (cr2 & STM32F7_I2C_CR2_RD_WRN)
1064 			cr1 |= STM32F7_I2C_CR1_RXDMAEN;
1065 		else
1066 			cr1 |= STM32F7_I2C_CR1_TXDMAEN;
1067 	}
1068 
1069 	/* Set Start bit */
1070 	cr2 |= STM32F7_I2C_CR2_START;
1071 
1072 	i2c_dev->master_mode = true;
1073 
1074 	/* Write configurations registers */
1075 	writel_relaxed(cr1, base + STM32F7_I2C_CR1);
1076 	writel_relaxed(cr2, base + STM32F7_I2C_CR2);
1077 
1078 	return 0;
1079 }
1080 
1081 static void stm32f7_i2c_smbus_rep_start(struct stm32f7_i2c_dev *i2c_dev)
1082 {
1083 	struct stm32f7_i2c_msg *f7_msg = &i2c_dev->f7_msg;
1084 	void __iomem *base = i2c_dev->base;
1085 	u32 cr1, cr2;
1086 	int ret;
1087 
1088 	cr2 = readl_relaxed(base + STM32F7_I2C_CR2);
1089 	cr1 = readl_relaxed(base + STM32F7_I2C_CR1);
1090 
1091 	/* Set transfer direction */
1092 	cr2 |= STM32F7_I2C_CR2_RD_WRN;
1093 
1094 	switch (f7_msg->size) {
1095 	case I2C_SMBUS_BYTE_DATA:
1096 		f7_msg->count = 1;
1097 		break;
1098 	case I2C_SMBUS_WORD_DATA:
1099 	case I2C_SMBUS_PROC_CALL:
1100 		f7_msg->count = 2;
1101 		break;
1102 	case I2C_SMBUS_BLOCK_DATA:
1103 	case I2C_SMBUS_BLOCK_PROC_CALL:
1104 		f7_msg->count = 1;
1105 		cr2 |= STM32F7_I2C_CR2_RELOAD;
1106 		break;
1107 	}
1108 
1109 	f7_msg->buf = f7_msg->smbus_buf;
1110 	f7_msg->stop = true;
1111 
1112 	/* Add one byte for PEC if needed */
1113 	if (cr1 & STM32F7_I2C_CR1_PECEN)
1114 		f7_msg->count++;
1115 
1116 	/* Set number of bytes to be transferred */
1117 	cr2 &= ~(STM32F7_I2C_CR2_NBYTES_MASK);
1118 	cr2 |= STM32F7_I2C_CR2_NBYTES(f7_msg->count);
1119 
1120 	/*
1121 	 * Configure RX/TX interrupt:
1122 	 */
1123 	cr1 &= ~(STM32F7_I2C_CR1_RXIE | STM32F7_I2C_CR1_TXIE);
1124 	cr1 |= STM32F7_I2C_CR1_RXIE;
1125 
1126 	/*
1127 	 * Configure DMA or enable RX/TX interrupt:
1128 	 * For I2C_SMBUS_BLOCK_DATA and I2C_SMBUS_BLOCK_PROC_CALL we don't use
1129 	 * dma as we don't know in advance how many data will be received
1130 	 */
1131 	cr1 &= ~(STM32F7_I2C_CR1_RXIE | STM32F7_I2C_CR1_TXIE |
1132 		 STM32F7_I2C_CR1_RXDMAEN | STM32F7_I2C_CR1_TXDMAEN);
1133 
1134 	i2c_dev->use_dma = false;
1135 	if (i2c_dev->dma && f7_msg->count >= STM32F7_I2C_DMA_LEN_MIN &&
1136 	    f7_msg->size != I2C_SMBUS_BLOCK_DATA &&
1137 	    f7_msg->size != I2C_SMBUS_BLOCK_PROC_CALL) {
1138 		ret = stm32_i2c_prep_dma_xfer(i2c_dev->dev, i2c_dev->dma,
1139 					      cr2 & STM32F7_I2C_CR2_RD_WRN,
1140 					      f7_msg->count, f7_msg->buf,
1141 					      stm32f7_i2c_dma_callback,
1142 					      i2c_dev);
1143 
1144 		if (!ret)
1145 			i2c_dev->use_dma = true;
1146 		else
1147 			dev_warn(i2c_dev->dev, "can't use DMA\n");
1148 	}
1149 
1150 	if (!i2c_dev->use_dma)
1151 		cr1 |= STM32F7_I2C_CR1_RXIE;
1152 	else
1153 		cr1 |= STM32F7_I2C_CR1_RXDMAEN;
1154 
1155 	/* Configure Repeated Start */
1156 	cr2 |= STM32F7_I2C_CR2_START;
1157 
1158 	/* Write configurations registers */
1159 	writel_relaxed(cr1, base + STM32F7_I2C_CR1);
1160 	writel_relaxed(cr2, base + STM32F7_I2C_CR2);
1161 }
1162 
1163 static int stm32f7_i2c_smbus_check_pec(struct stm32f7_i2c_dev *i2c_dev)
1164 {
1165 	struct stm32f7_i2c_msg *f7_msg = &i2c_dev->f7_msg;
1166 	u8 count, internal_pec, received_pec;
1167 
1168 	internal_pec = readl_relaxed(i2c_dev->base + STM32F7_I2C_PECR);
1169 
1170 	switch (f7_msg->size) {
1171 	case I2C_SMBUS_BYTE:
1172 	case I2C_SMBUS_BYTE_DATA:
1173 		received_pec = f7_msg->smbus_buf[1];
1174 		break;
1175 	case I2C_SMBUS_WORD_DATA:
1176 	case I2C_SMBUS_PROC_CALL:
1177 		received_pec = f7_msg->smbus_buf[2];
1178 		break;
1179 	case I2C_SMBUS_BLOCK_DATA:
1180 	case I2C_SMBUS_BLOCK_PROC_CALL:
1181 		count = f7_msg->smbus_buf[0];
1182 		received_pec = f7_msg->smbus_buf[count];
1183 		break;
1184 	default:
1185 		dev_err(i2c_dev->dev, "Unsupported smbus protocol for PEC\n");
1186 		return -EINVAL;
1187 	}
1188 
1189 	if (internal_pec != received_pec) {
1190 		dev_err(i2c_dev->dev, "Bad PEC 0x%02x vs. 0x%02x\n",
1191 			internal_pec, received_pec);
1192 		return -EBADMSG;
1193 	}
1194 
1195 	return 0;
1196 }
1197 
1198 static bool stm32f7_i2c_is_addr_match(struct i2c_client *slave, u32 addcode)
1199 {
1200 	u32 addr;
1201 
1202 	if (!slave)
1203 		return false;
1204 
1205 	if (slave->flags & I2C_CLIENT_TEN) {
1206 		/*
1207 		 * For 10-bit addr, addcode = 11110XY with
1208 		 * X = Bit 9 of slave address
1209 		 * Y = Bit 8 of slave address
1210 		 */
1211 		addr = slave->addr >> 8;
1212 		addr |= 0x78;
1213 		if (addr == addcode)
1214 			return true;
1215 	} else {
1216 		addr = slave->addr & 0x7f;
1217 		if (addr == addcode)
1218 			return true;
1219 	}
1220 
1221 	return false;
1222 }
1223 
1224 static void stm32f7_i2c_slave_start(struct stm32f7_i2c_dev *i2c_dev)
1225 {
1226 	struct i2c_client *slave = i2c_dev->slave_running;
1227 	void __iomem *base = i2c_dev->base;
1228 	u32 mask;
1229 	u8 value = 0;
1230 
1231 	if (i2c_dev->slave_dir) {
1232 		/* Notify i2c slave that new read transfer is starting */
1233 		i2c_slave_event(slave, I2C_SLAVE_READ_REQUESTED, &value);
1234 
1235 		/*
1236 		 * Disable slave TX config in case of I2C combined message
1237 		 * (I2C Write followed by I2C Read)
1238 		 */
1239 		mask = STM32F7_I2C_CR2_RELOAD;
1240 		stm32f7_i2c_clr_bits(base + STM32F7_I2C_CR2, mask);
1241 		mask = STM32F7_I2C_CR1_SBC | STM32F7_I2C_CR1_RXIE |
1242 		       STM32F7_I2C_CR1_TCIE;
1243 		stm32f7_i2c_clr_bits(base + STM32F7_I2C_CR1, mask);
1244 
1245 		/* Enable TX empty, STOP, NACK interrupts */
1246 		mask =  STM32F7_I2C_CR1_STOPIE | STM32F7_I2C_CR1_NACKIE |
1247 			STM32F7_I2C_CR1_TXIE;
1248 		stm32f7_i2c_set_bits(base + STM32F7_I2C_CR1, mask);
1249 
1250 		/* Write 1st data byte */
1251 		writel_relaxed(value, base + STM32F7_I2C_TXDR);
1252 	} else {
1253 		/* Notify i2c slave that new write transfer is starting */
1254 		i2c_slave_event(slave, I2C_SLAVE_WRITE_REQUESTED, &value);
1255 
1256 		/* Set reload mode to be able to ACK/NACK each received byte */
1257 		mask = STM32F7_I2C_CR2_RELOAD;
1258 		stm32f7_i2c_set_bits(base + STM32F7_I2C_CR2, mask);
1259 
1260 		/*
1261 		 * Set STOP, NACK, RX empty and transfer complete interrupts.*
1262 		 * Set Slave Byte Control to be able to ACK/NACK each data
1263 		 * byte received
1264 		 */
1265 		mask =  STM32F7_I2C_CR1_STOPIE | STM32F7_I2C_CR1_NACKIE |
1266 			STM32F7_I2C_CR1_SBC | STM32F7_I2C_CR1_RXIE |
1267 			STM32F7_I2C_CR1_TCIE;
1268 		stm32f7_i2c_set_bits(base + STM32F7_I2C_CR1, mask);
1269 	}
1270 }
1271 
1272 static void stm32f7_i2c_slave_addr(struct stm32f7_i2c_dev *i2c_dev)
1273 {
1274 	void __iomem *base = i2c_dev->base;
1275 	u32 isr, addcode, dir, mask;
1276 	int i;
1277 
1278 	isr = readl_relaxed(i2c_dev->base + STM32F7_I2C_ISR);
1279 	addcode = STM32F7_I2C_ISR_ADDCODE_GET(isr);
1280 	dir = isr & STM32F7_I2C_ISR_DIR;
1281 
1282 	for (i = 0; i < STM32F7_I2C_MAX_SLAVE; i++) {
1283 		if (stm32f7_i2c_is_addr_match(i2c_dev->slave[i], addcode)) {
1284 			i2c_dev->slave_running = i2c_dev->slave[i];
1285 			i2c_dev->slave_dir = dir;
1286 
1287 			/* Start I2C slave processing */
1288 			stm32f7_i2c_slave_start(i2c_dev);
1289 
1290 			/* Clear ADDR flag */
1291 			mask = STM32F7_I2C_ICR_ADDRCF;
1292 			writel_relaxed(mask, base + STM32F7_I2C_ICR);
1293 			break;
1294 		}
1295 	}
1296 }
1297 
1298 static int stm32f7_i2c_get_slave_id(struct stm32f7_i2c_dev *i2c_dev,
1299 				    struct i2c_client *slave, int *id)
1300 {
1301 	int i;
1302 
1303 	for (i = 0; i < STM32F7_I2C_MAX_SLAVE; i++) {
1304 		if (i2c_dev->slave[i] == slave) {
1305 			*id = i;
1306 			return 0;
1307 		}
1308 	}
1309 
1310 	dev_err(i2c_dev->dev, "Slave 0x%x not registered\n", slave->addr);
1311 
1312 	return -ENODEV;
1313 }
1314 
1315 static int stm32f7_i2c_get_free_slave_id(struct stm32f7_i2c_dev *i2c_dev,
1316 					 struct i2c_client *slave, int *id)
1317 {
1318 	struct device *dev = i2c_dev->dev;
1319 	int i;
1320 
1321 	/*
1322 	 * slave[0] supports 7-bit and 10-bit slave address
1323 	 * slave[1] supports 7-bit slave address only
1324 	 */
1325 	for (i = STM32F7_I2C_MAX_SLAVE - 1; i >= 0; i--) {
1326 		if (i == 1 && (slave->flags & I2C_CLIENT_TEN))
1327 			continue;
1328 		if (!i2c_dev->slave[i]) {
1329 			*id = i;
1330 			return 0;
1331 		}
1332 	}
1333 
1334 	dev_err(dev, "Slave 0x%x could not be registered\n", slave->addr);
1335 
1336 	return -EINVAL;
1337 }
1338 
1339 static bool stm32f7_i2c_is_slave_registered(struct stm32f7_i2c_dev *i2c_dev)
1340 {
1341 	int i;
1342 
1343 	for (i = 0; i < STM32F7_I2C_MAX_SLAVE; i++) {
1344 		if (i2c_dev->slave[i])
1345 			return true;
1346 	}
1347 
1348 	return false;
1349 }
1350 
1351 static bool stm32f7_i2c_is_slave_busy(struct stm32f7_i2c_dev *i2c_dev)
1352 {
1353 	int i, busy;
1354 
1355 	busy = 0;
1356 	for (i = 0; i < STM32F7_I2C_MAX_SLAVE; i++) {
1357 		if (i2c_dev->slave[i])
1358 			busy++;
1359 	}
1360 
1361 	return i == busy;
1362 }
1363 
1364 static irqreturn_t stm32f7_i2c_slave_isr_event(struct stm32f7_i2c_dev *i2c_dev)
1365 {
1366 	void __iomem *base = i2c_dev->base;
1367 	u32 cr2, status, mask;
1368 	u8 val;
1369 	int ret;
1370 
1371 	status = readl_relaxed(i2c_dev->base + STM32F7_I2C_ISR);
1372 
1373 	/* Slave transmitter mode */
1374 	if (status & STM32F7_I2C_ISR_TXIS) {
1375 		i2c_slave_event(i2c_dev->slave_running,
1376 				I2C_SLAVE_READ_PROCESSED,
1377 				&val);
1378 
1379 		/* Write data byte */
1380 		writel_relaxed(val, base + STM32F7_I2C_TXDR);
1381 	}
1382 
1383 	/* Transfer Complete Reload for Slave receiver mode */
1384 	if (status & STM32F7_I2C_ISR_TCR || status & STM32F7_I2C_ISR_RXNE) {
1385 		/*
1386 		 * Read data byte then set NBYTES to receive next byte or NACK
1387 		 * the current received byte
1388 		 */
1389 		val = readb_relaxed(i2c_dev->base + STM32F7_I2C_RXDR);
1390 		ret = i2c_slave_event(i2c_dev->slave_running,
1391 				      I2C_SLAVE_WRITE_RECEIVED,
1392 				      &val);
1393 		if (!ret) {
1394 			cr2 = readl_relaxed(i2c_dev->base + STM32F7_I2C_CR2);
1395 			cr2 |= STM32F7_I2C_CR2_NBYTES(1);
1396 			writel_relaxed(cr2, i2c_dev->base + STM32F7_I2C_CR2);
1397 		} else {
1398 			mask = STM32F7_I2C_CR2_NACK;
1399 			stm32f7_i2c_set_bits(base + STM32F7_I2C_CR2, mask);
1400 		}
1401 	}
1402 
1403 	/* NACK received */
1404 	if (status & STM32F7_I2C_ISR_NACKF) {
1405 		dev_dbg(i2c_dev->dev, "<%s>: Receive NACK\n", __func__);
1406 		writel_relaxed(STM32F7_I2C_ICR_NACKCF, base + STM32F7_I2C_ICR);
1407 	}
1408 
1409 	/* STOP received */
1410 	if (status & STM32F7_I2C_ISR_STOPF) {
1411 		/* Disable interrupts */
1412 		stm32f7_i2c_disable_irq(i2c_dev, STM32F7_I2C_XFER_IRQ_MASK);
1413 
1414 		if (i2c_dev->slave_dir) {
1415 			/*
1416 			 * Flush TX buffer in order to not used the byte in
1417 			 * TXDR for the next transfer
1418 			 */
1419 			mask = STM32F7_I2C_ISR_TXE;
1420 			stm32f7_i2c_set_bits(base + STM32F7_I2C_ISR, mask);
1421 		}
1422 
1423 		/* Clear STOP flag */
1424 		writel_relaxed(STM32F7_I2C_ICR_STOPCF, base + STM32F7_I2C_ICR);
1425 
1426 		/* Notify i2c slave that a STOP flag has been detected */
1427 		i2c_slave_event(i2c_dev->slave_running, I2C_SLAVE_STOP, &val);
1428 
1429 		i2c_dev->slave_running = NULL;
1430 	}
1431 
1432 	/* Address match received */
1433 	if (status & STM32F7_I2C_ISR_ADDR)
1434 		stm32f7_i2c_slave_addr(i2c_dev);
1435 
1436 	return IRQ_HANDLED;
1437 }
1438 
1439 static irqreturn_t stm32f7_i2c_isr_event(int irq, void *data)
1440 {
1441 	struct stm32f7_i2c_dev *i2c_dev = data;
1442 	struct stm32f7_i2c_msg *f7_msg = &i2c_dev->f7_msg;
1443 	void __iomem *base = i2c_dev->base;
1444 	u32 status, mask;
1445 	int ret = IRQ_HANDLED;
1446 
1447 	/* Check if the interrupt if for a slave device */
1448 	if (!i2c_dev->master_mode) {
1449 		ret = stm32f7_i2c_slave_isr_event(i2c_dev);
1450 		return ret;
1451 	}
1452 
1453 	status = readl_relaxed(i2c_dev->base + STM32F7_I2C_ISR);
1454 
1455 	/* Tx empty */
1456 	if (status & STM32F7_I2C_ISR_TXIS)
1457 		stm32f7_i2c_write_tx_data(i2c_dev);
1458 
1459 	/* RX not empty */
1460 	if (status & STM32F7_I2C_ISR_RXNE)
1461 		stm32f7_i2c_read_rx_data(i2c_dev);
1462 
1463 	/* NACK received */
1464 	if (status & STM32F7_I2C_ISR_NACKF) {
1465 		dev_dbg(i2c_dev->dev, "<%s>: Receive NACK\n", __func__);
1466 		writel_relaxed(STM32F7_I2C_ICR_NACKCF, base + STM32F7_I2C_ICR);
1467 		f7_msg->result = -ENXIO;
1468 	}
1469 
1470 	/* STOP detection flag */
1471 	if (status & STM32F7_I2C_ISR_STOPF) {
1472 		/* Disable interrupts */
1473 		if (stm32f7_i2c_is_slave_registered(i2c_dev))
1474 			mask = STM32F7_I2C_XFER_IRQ_MASK;
1475 		else
1476 			mask = STM32F7_I2C_ALL_IRQ_MASK;
1477 		stm32f7_i2c_disable_irq(i2c_dev, mask);
1478 
1479 		/* Clear STOP flag */
1480 		writel_relaxed(STM32F7_I2C_ICR_STOPCF, base + STM32F7_I2C_ICR);
1481 
1482 		if (i2c_dev->use_dma) {
1483 			ret = IRQ_WAKE_THREAD;
1484 		} else {
1485 			i2c_dev->master_mode = false;
1486 			complete(&i2c_dev->complete);
1487 		}
1488 	}
1489 
1490 	/* Transfer complete */
1491 	if (status & STM32F7_I2C_ISR_TC) {
1492 		if (f7_msg->stop) {
1493 			mask = STM32F7_I2C_CR2_STOP;
1494 			stm32f7_i2c_set_bits(base + STM32F7_I2C_CR2, mask);
1495 		} else if (i2c_dev->use_dma) {
1496 			ret = IRQ_WAKE_THREAD;
1497 		} else if (f7_msg->smbus) {
1498 			stm32f7_i2c_smbus_rep_start(i2c_dev);
1499 		} else {
1500 			i2c_dev->msg_id++;
1501 			i2c_dev->msg++;
1502 			stm32f7_i2c_xfer_msg(i2c_dev, i2c_dev->msg);
1503 		}
1504 	}
1505 
1506 	if (status & STM32F7_I2C_ISR_TCR) {
1507 		if (f7_msg->smbus)
1508 			stm32f7_i2c_smbus_reload(i2c_dev);
1509 		else
1510 			stm32f7_i2c_reload(i2c_dev);
1511 	}
1512 
1513 	return ret;
1514 }
1515 
1516 static irqreturn_t stm32f7_i2c_isr_event_thread(int irq, void *data)
1517 {
1518 	struct stm32f7_i2c_dev *i2c_dev = data;
1519 	struct stm32f7_i2c_msg *f7_msg = &i2c_dev->f7_msg;
1520 	struct stm32_i2c_dma *dma = i2c_dev->dma;
1521 	u32 status;
1522 	int ret;
1523 
1524 	/*
1525 	 * Wait for dma transfer completion before sending next message or
1526 	 * notity the end of xfer to the client
1527 	 */
1528 	ret = wait_for_completion_timeout(&i2c_dev->dma->dma_complete, HZ);
1529 	if (!ret) {
1530 		dev_dbg(i2c_dev->dev, "<%s>: Timed out\n", __func__);
1531 		stm32f7_i2c_disable_dma_req(i2c_dev);
1532 		dmaengine_terminate_all(dma->chan_using);
1533 		f7_msg->result = -ETIMEDOUT;
1534 	}
1535 
1536 	status = readl_relaxed(i2c_dev->base + STM32F7_I2C_ISR);
1537 
1538 	if (status & STM32F7_I2C_ISR_TC) {
1539 		if (f7_msg->smbus) {
1540 			stm32f7_i2c_smbus_rep_start(i2c_dev);
1541 		} else {
1542 			i2c_dev->msg_id++;
1543 			i2c_dev->msg++;
1544 			stm32f7_i2c_xfer_msg(i2c_dev, i2c_dev->msg);
1545 		}
1546 	} else {
1547 		i2c_dev->master_mode = false;
1548 		complete(&i2c_dev->complete);
1549 	}
1550 
1551 	return IRQ_HANDLED;
1552 }
1553 
1554 static irqreturn_t stm32f7_i2c_isr_error(int irq, void *data)
1555 {
1556 	struct stm32f7_i2c_dev *i2c_dev = data;
1557 	struct stm32f7_i2c_msg *f7_msg = &i2c_dev->f7_msg;
1558 	void __iomem *base = i2c_dev->base;
1559 	struct device *dev = i2c_dev->dev;
1560 	struct stm32_i2c_dma *dma = i2c_dev->dma;
1561 	u32 status;
1562 
1563 	status = readl_relaxed(i2c_dev->base + STM32F7_I2C_ISR);
1564 
1565 	/* Bus error */
1566 	if (status & STM32F7_I2C_ISR_BERR) {
1567 		dev_err(dev, "<%s>: Bus error\n", __func__);
1568 		writel_relaxed(STM32F7_I2C_ICR_BERRCF, base + STM32F7_I2C_ICR);
1569 		stm32f7_i2c_release_bus(&i2c_dev->adap);
1570 		f7_msg->result = -EIO;
1571 	}
1572 
1573 	/* Arbitration loss */
1574 	if (status & STM32F7_I2C_ISR_ARLO) {
1575 		dev_dbg(dev, "<%s>: Arbitration loss\n", __func__);
1576 		writel_relaxed(STM32F7_I2C_ICR_ARLOCF, base + STM32F7_I2C_ICR);
1577 		f7_msg->result = -EAGAIN;
1578 	}
1579 
1580 	if (status & STM32F7_I2C_ISR_PECERR) {
1581 		dev_err(dev, "<%s>: PEC error in reception\n", __func__);
1582 		writel_relaxed(STM32F7_I2C_ICR_PECCF, base + STM32F7_I2C_ICR);
1583 		f7_msg->result = -EINVAL;
1584 	}
1585 
1586 	if (!i2c_dev->slave_running) {
1587 		u32 mask;
1588 		/* Disable interrupts */
1589 		if (stm32f7_i2c_is_slave_registered(i2c_dev))
1590 			mask = STM32F7_I2C_XFER_IRQ_MASK;
1591 		else
1592 			mask = STM32F7_I2C_ALL_IRQ_MASK;
1593 		stm32f7_i2c_disable_irq(i2c_dev, mask);
1594 	}
1595 
1596 	/* Disable dma */
1597 	if (i2c_dev->use_dma) {
1598 		stm32f7_i2c_disable_dma_req(i2c_dev);
1599 		dmaengine_terminate_all(dma->chan_using);
1600 	}
1601 
1602 	i2c_dev->master_mode = false;
1603 	complete(&i2c_dev->complete);
1604 
1605 	return IRQ_HANDLED;
1606 }
1607 
1608 static int stm32f7_i2c_xfer(struct i2c_adapter *i2c_adap,
1609 			    struct i2c_msg msgs[], int num)
1610 {
1611 	struct stm32f7_i2c_dev *i2c_dev = i2c_get_adapdata(i2c_adap);
1612 	struct stm32f7_i2c_msg *f7_msg = &i2c_dev->f7_msg;
1613 	struct stm32_i2c_dma *dma = i2c_dev->dma;
1614 	unsigned long time_left;
1615 	int ret;
1616 
1617 	i2c_dev->msg = msgs;
1618 	i2c_dev->msg_num = num;
1619 	i2c_dev->msg_id = 0;
1620 	f7_msg->smbus = false;
1621 
1622 	ret = pm_runtime_get_sync(i2c_dev->dev);
1623 	if (ret < 0)
1624 		return ret;
1625 
1626 	ret = stm32f7_i2c_wait_free_bus(i2c_dev);
1627 	if (ret)
1628 		goto pm_free;
1629 
1630 	stm32f7_i2c_xfer_msg(i2c_dev, msgs);
1631 
1632 	time_left = wait_for_completion_timeout(&i2c_dev->complete,
1633 						i2c_dev->adap.timeout);
1634 	ret = f7_msg->result;
1635 
1636 	if (!time_left) {
1637 		dev_dbg(i2c_dev->dev, "Access to slave 0x%x timed out\n",
1638 			i2c_dev->msg->addr);
1639 		if (i2c_dev->use_dma)
1640 			dmaengine_terminate_all(dma->chan_using);
1641 		ret = -ETIMEDOUT;
1642 	}
1643 
1644 pm_free:
1645 	pm_runtime_mark_last_busy(i2c_dev->dev);
1646 	pm_runtime_put_autosuspend(i2c_dev->dev);
1647 
1648 	return (ret < 0) ? ret : num;
1649 }
1650 
1651 static int stm32f7_i2c_smbus_xfer(struct i2c_adapter *adapter, u16 addr,
1652 				  unsigned short flags, char read_write,
1653 				  u8 command, int size,
1654 				  union i2c_smbus_data *data)
1655 {
1656 	struct stm32f7_i2c_dev *i2c_dev = i2c_get_adapdata(adapter);
1657 	struct stm32f7_i2c_msg *f7_msg = &i2c_dev->f7_msg;
1658 	struct stm32_i2c_dma *dma = i2c_dev->dma;
1659 	struct device *dev = i2c_dev->dev;
1660 	unsigned long timeout;
1661 	int i, ret;
1662 
1663 	f7_msg->addr = addr;
1664 	f7_msg->size = size;
1665 	f7_msg->read_write = read_write;
1666 	f7_msg->smbus = true;
1667 
1668 	ret = pm_runtime_get_sync(dev);
1669 	if (ret < 0)
1670 		return ret;
1671 
1672 	ret = stm32f7_i2c_wait_free_bus(i2c_dev);
1673 	if (ret)
1674 		goto pm_free;
1675 
1676 	ret = stm32f7_i2c_smbus_xfer_msg(i2c_dev, flags, command, data);
1677 	if (ret)
1678 		goto pm_free;
1679 
1680 	timeout = wait_for_completion_timeout(&i2c_dev->complete,
1681 					      i2c_dev->adap.timeout);
1682 	ret = f7_msg->result;
1683 	if (ret)
1684 		goto pm_free;
1685 
1686 	if (!timeout) {
1687 		dev_dbg(dev, "Access to slave 0x%x timed out\n", f7_msg->addr);
1688 		if (i2c_dev->use_dma)
1689 			dmaengine_terminate_all(dma->chan_using);
1690 		ret = -ETIMEDOUT;
1691 		goto pm_free;
1692 	}
1693 
1694 	/* Check PEC */
1695 	if ((flags & I2C_CLIENT_PEC) && size != I2C_SMBUS_QUICK && read_write) {
1696 		ret = stm32f7_i2c_smbus_check_pec(i2c_dev);
1697 		if (ret)
1698 			goto pm_free;
1699 	}
1700 
1701 	if (read_write && size != I2C_SMBUS_QUICK) {
1702 		switch (size) {
1703 		case I2C_SMBUS_BYTE:
1704 		case I2C_SMBUS_BYTE_DATA:
1705 			data->byte = f7_msg->smbus_buf[0];
1706 		break;
1707 		case I2C_SMBUS_WORD_DATA:
1708 		case I2C_SMBUS_PROC_CALL:
1709 			data->word = f7_msg->smbus_buf[0] |
1710 				(f7_msg->smbus_buf[1] << 8);
1711 		break;
1712 		case I2C_SMBUS_BLOCK_DATA:
1713 		case I2C_SMBUS_BLOCK_PROC_CALL:
1714 		for (i = 0; i <= f7_msg->smbus_buf[0]; i++)
1715 			data->block[i] = f7_msg->smbus_buf[i];
1716 		break;
1717 		default:
1718 			dev_err(dev, "Unsupported smbus transaction\n");
1719 			ret = -EINVAL;
1720 		}
1721 	}
1722 
1723 pm_free:
1724 	pm_runtime_mark_last_busy(dev);
1725 	pm_runtime_put_autosuspend(dev);
1726 	return ret;
1727 }
1728 
1729 static void stm32f7_i2c_enable_wakeup(struct stm32f7_i2c_dev *i2c_dev,
1730 				      bool enable)
1731 {
1732 	void __iomem *base = i2c_dev->base;
1733 	u32 mask = STM32F7_I2C_CR1_WUPEN;
1734 
1735 	if (!i2c_dev->wakeup_src)
1736 		return;
1737 
1738 	if (enable) {
1739 		device_set_wakeup_enable(i2c_dev->dev, true);
1740 		stm32f7_i2c_set_bits(base + STM32F7_I2C_CR1, mask);
1741 	} else {
1742 		device_set_wakeup_enable(i2c_dev->dev, false);
1743 		stm32f7_i2c_clr_bits(base + STM32F7_I2C_CR1, mask);
1744 	}
1745 }
1746 
1747 static int stm32f7_i2c_reg_slave(struct i2c_client *slave)
1748 {
1749 	struct stm32f7_i2c_dev *i2c_dev = i2c_get_adapdata(slave->adapter);
1750 	void __iomem *base = i2c_dev->base;
1751 	struct device *dev = i2c_dev->dev;
1752 	u32 oar1, oar2, mask;
1753 	int id, ret;
1754 
1755 	if (slave->flags & I2C_CLIENT_PEC) {
1756 		dev_err(dev, "SMBus PEC not supported in slave mode\n");
1757 		return -EINVAL;
1758 	}
1759 
1760 	if (stm32f7_i2c_is_slave_busy(i2c_dev)) {
1761 		dev_err(dev, "Too much slave registered\n");
1762 		return -EBUSY;
1763 	}
1764 
1765 	ret = stm32f7_i2c_get_free_slave_id(i2c_dev, slave, &id);
1766 	if (ret)
1767 		return ret;
1768 
1769 	ret = pm_runtime_get_sync(dev);
1770 	if (ret < 0)
1771 		return ret;
1772 
1773 	if (!stm32f7_i2c_is_slave_registered(i2c_dev))
1774 		stm32f7_i2c_enable_wakeup(i2c_dev, true);
1775 
1776 	if (id == 0) {
1777 		/* Configure Own Address 1 */
1778 		oar1 = readl_relaxed(i2c_dev->base + STM32F7_I2C_OAR1);
1779 		oar1 &= ~STM32F7_I2C_OAR1_MASK;
1780 		if (slave->flags & I2C_CLIENT_TEN) {
1781 			oar1 |= STM32F7_I2C_OAR1_OA1_10(slave->addr);
1782 			oar1 |= STM32F7_I2C_OAR1_OA1MODE;
1783 		} else {
1784 			oar1 |= STM32F7_I2C_OAR1_OA1_7(slave->addr);
1785 		}
1786 		oar1 |= STM32F7_I2C_OAR1_OA1EN;
1787 		i2c_dev->slave[id] = slave;
1788 		writel_relaxed(oar1, i2c_dev->base + STM32F7_I2C_OAR1);
1789 	} else if (id == 1) {
1790 		/* Configure Own Address 2 */
1791 		oar2 = readl_relaxed(i2c_dev->base + STM32F7_I2C_OAR2);
1792 		oar2 &= ~STM32F7_I2C_OAR2_MASK;
1793 		if (slave->flags & I2C_CLIENT_TEN) {
1794 			ret = -EOPNOTSUPP;
1795 			goto pm_free;
1796 		}
1797 
1798 		oar2 |= STM32F7_I2C_OAR2_OA2_7(slave->addr);
1799 		oar2 |= STM32F7_I2C_OAR2_OA2EN;
1800 		i2c_dev->slave[id] = slave;
1801 		writel_relaxed(oar2, i2c_dev->base + STM32F7_I2C_OAR2);
1802 	} else {
1803 		ret = -ENODEV;
1804 		goto pm_free;
1805 	}
1806 
1807 	/* Enable ACK */
1808 	stm32f7_i2c_clr_bits(base + STM32F7_I2C_CR2, STM32F7_I2C_CR2_NACK);
1809 
1810 	/* Enable Address match interrupt, error interrupt and enable I2C  */
1811 	mask = STM32F7_I2C_CR1_ADDRIE | STM32F7_I2C_CR1_ERRIE |
1812 		STM32F7_I2C_CR1_PE;
1813 	stm32f7_i2c_set_bits(base + STM32F7_I2C_CR1, mask);
1814 
1815 	ret = 0;
1816 pm_free:
1817 	if (!stm32f7_i2c_is_slave_registered(i2c_dev))
1818 		stm32f7_i2c_enable_wakeup(i2c_dev, false);
1819 
1820 	pm_runtime_mark_last_busy(dev);
1821 	pm_runtime_put_autosuspend(dev);
1822 
1823 	return ret;
1824 }
1825 
1826 static int stm32f7_i2c_unreg_slave(struct i2c_client *slave)
1827 {
1828 	struct stm32f7_i2c_dev *i2c_dev = i2c_get_adapdata(slave->adapter);
1829 	void __iomem *base = i2c_dev->base;
1830 	u32 mask;
1831 	int id, ret;
1832 
1833 	ret = stm32f7_i2c_get_slave_id(i2c_dev, slave, &id);
1834 	if (ret)
1835 		return ret;
1836 
1837 	WARN_ON(!i2c_dev->slave[id]);
1838 
1839 	ret = pm_runtime_get_sync(i2c_dev->dev);
1840 	if (ret < 0)
1841 		return ret;
1842 
1843 	if (id == 0) {
1844 		mask = STM32F7_I2C_OAR1_OA1EN;
1845 		stm32f7_i2c_clr_bits(base + STM32F7_I2C_OAR1, mask);
1846 	} else {
1847 		mask = STM32F7_I2C_OAR2_OA2EN;
1848 		stm32f7_i2c_clr_bits(base + STM32F7_I2C_OAR2, mask);
1849 	}
1850 
1851 	i2c_dev->slave[id] = NULL;
1852 
1853 	if (!stm32f7_i2c_is_slave_registered(i2c_dev)) {
1854 		stm32f7_i2c_disable_irq(i2c_dev, STM32F7_I2C_ALL_IRQ_MASK);
1855 		stm32f7_i2c_enable_wakeup(i2c_dev, false);
1856 	}
1857 
1858 	pm_runtime_mark_last_busy(i2c_dev->dev);
1859 	pm_runtime_put_autosuspend(i2c_dev->dev);
1860 
1861 	return 0;
1862 }
1863 
1864 static int stm32f7_i2c_write_fm_plus_bits(struct stm32f7_i2c_dev *i2c_dev,
1865 					  bool enable)
1866 {
1867 	int ret;
1868 
1869 	if (i2c_dev->speed != STM32_I2C_SPEED_FAST_PLUS ||
1870 	    IS_ERR_OR_NULL(i2c_dev->regmap))
1871 		/* Optional */
1872 		return 0;
1873 
1874 	if (i2c_dev->fmp_sreg == i2c_dev->fmp_creg)
1875 		ret = regmap_update_bits(i2c_dev->regmap,
1876 					 i2c_dev->fmp_sreg,
1877 					 i2c_dev->fmp_mask,
1878 					 enable ? i2c_dev->fmp_mask : 0);
1879 	else
1880 		ret = regmap_write(i2c_dev->regmap,
1881 				   enable ? i2c_dev->fmp_sreg :
1882 					    i2c_dev->fmp_creg,
1883 				   i2c_dev->fmp_mask);
1884 
1885 	return ret;
1886 }
1887 
1888 static int stm32f7_i2c_setup_fm_plus_bits(struct platform_device *pdev,
1889 					  struct stm32f7_i2c_dev *i2c_dev)
1890 {
1891 	struct device_node *np = pdev->dev.of_node;
1892 	int ret;
1893 
1894 	i2c_dev->regmap = syscon_regmap_lookup_by_phandle(np, "st,syscfg-fmp");
1895 	if (IS_ERR(i2c_dev->regmap))
1896 		/* Optional */
1897 		return 0;
1898 
1899 	ret = of_property_read_u32_index(np, "st,syscfg-fmp", 1,
1900 					 &i2c_dev->fmp_sreg);
1901 	if (ret)
1902 		return ret;
1903 
1904 	i2c_dev->fmp_creg = i2c_dev->fmp_sreg +
1905 			       i2c_dev->setup.fmp_clr_offset;
1906 
1907 	return of_property_read_u32_index(np, "st,syscfg-fmp", 2,
1908 					  &i2c_dev->fmp_mask);
1909 }
1910 
1911 static u32 stm32f7_i2c_func(struct i2c_adapter *adap)
1912 {
1913 	return I2C_FUNC_I2C | I2C_FUNC_10BIT_ADDR | I2C_FUNC_SLAVE |
1914 		I2C_FUNC_SMBUS_QUICK | I2C_FUNC_SMBUS_BYTE |
1915 		I2C_FUNC_SMBUS_BYTE_DATA | I2C_FUNC_SMBUS_WORD_DATA |
1916 		I2C_FUNC_SMBUS_BLOCK_DATA | I2C_FUNC_SMBUS_BLOCK_PROC_CALL |
1917 		I2C_FUNC_SMBUS_PROC_CALL | I2C_FUNC_SMBUS_PEC |
1918 		I2C_FUNC_SMBUS_I2C_BLOCK;
1919 }
1920 
1921 static const struct i2c_algorithm stm32f7_i2c_algo = {
1922 	.master_xfer = stm32f7_i2c_xfer,
1923 	.smbus_xfer = stm32f7_i2c_smbus_xfer,
1924 	.functionality = stm32f7_i2c_func,
1925 	.reg_slave = stm32f7_i2c_reg_slave,
1926 	.unreg_slave = stm32f7_i2c_unreg_slave,
1927 };
1928 
1929 static int stm32f7_i2c_probe(struct platform_device *pdev)
1930 {
1931 	struct stm32f7_i2c_dev *i2c_dev;
1932 	const struct stm32f7_i2c_setup *setup;
1933 	struct resource *res;
1934 	struct i2c_adapter *adap;
1935 	struct reset_control *rst;
1936 	dma_addr_t phy_addr;
1937 	int irq_error, irq_event, ret;
1938 
1939 	i2c_dev = devm_kzalloc(&pdev->dev, sizeof(*i2c_dev), GFP_KERNEL);
1940 	if (!i2c_dev)
1941 		return -ENOMEM;
1942 
1943 	res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
1944 	i2c_dev->base = devm_ioremap_resource(&pdev->dev, res);
1945 	if (IS_ERR(i2c_dev->base))
1946 		return PTR_ERR(i2c_dev->base);
1947 	phy_addr = (dma_addr_t)res->start;
1948 
1949 	irq_event = platform_get_irq(pdev, 0);
1950 	if (irq_event <= 0) {
1951 		if (irq_event != -EPROBE_DEFER)
1952 			dev_err(&pdev->dev, "Failed to get IRQ event: %d\n",
1953 				irq_event);
1954 		return irq_event ? : -ENOENT;
1955 	}
1956 
1957 	irq_error = platform_get_irq(pdev, 1);
1958 	if (irq_error <= 0) {
1959 		if (irq_error != -EPROBE_DEFER)
1960 			dev_err(&pdev->dev, "Failed to get IRQ error: %d\n",
1961 				irq_error);
1962 		return irq_error ? : -ENOENT;
1963 	}
1964 
1965 	i2c_dev->wakeup_src = of_property_read_bool(pdev->dev.of_node,
1966 						    "wakeup-source");
1967 
1968 	i2c_dev->clk = devm_clk_get(&pdev->dev, NULL);
1969 	if (IS_ERR(i2c_dev->clk)) {
1970 		dev_err(&pdev->dev, "Error: Missing controller clock\n");
1971 		return PTR_ERR(i2c_dev->clk);
1972 	}
1973 
1974 	ret = clk_prepare_enable(i2c_dev->clk);
1975 	if (ret) {
1976 		dev_err(&pdev->dev, "Failed to prepare_enable clock\n");
1977 		return ret;
1978 	}
1979 
1980 	rst = devm_reset_control_get(&pdev->dev, NULL);
1981 	if (IS_ERR(rst)) {
1982 		dev_err(&pdev->dev, "Error: Missing controller reset\n");
1983 		ret = PTR_ERR(rst);
1984 		goto clk_free;
1985 	}
1986 	reset_control_assert(rst);
1987 	udelay(2);
1988 	reset_control_deassert(rst);
1989 
1990 	i2c_dev->dev = &pdev->dev;
1991 
1992 	ret = devm_request_threaded_irq(&pdev->dev, irq_event,
1993 					stm32f7_i2c_isr_event,
1994 					stm32f7_i2c_isr_event_thread,
1995 					IRQF_ONESHOT,
1996 					pdev->name, i2c_dev);
1997 	if (ret) {
1998 		dev_err(&pdev->dev, "Failed to request irq event %i\n",
1999 			irq_event);
2000 		goto clk_free;
2001 	}
2002 
2003 	ret = devm_request_irq(&pdev->dev, irq_error, stm32f7_i2c_isr_error, 0,
2004 			       pdev->name, i2c_dev);
2005 	if (ret) {
2006 		dev_err(&pdev->dev, "Failed to request irq error %i\n",
2007 			irq_error);
2008 		goto clk_free;
2009 	}
2010 
2011 	setup = of_device_get_match_data(&pdev->dev);
2012 	if (!setup) {
2013 		dev_err(&pdev->dev, "Can't get device data\n");
2014 		ret = -ENODEV;
2015 		goto clk_free;
2016 	}
2017 	i2c_dev->setup = *setup;
2018 
2019 	ret = stm32f7_i2c_setup_timing(i2c_dev, &i2c_dev->setup);
2020 	if (ret)
2021 		goto clk_free;
2022 
2023 	if (i2c_dev->speed == STM32_I2C_SPEED_FAST_PLUS) {
2024 		ret = stm32f7_i2c_setup_fm_plus_bits(pdev, i2c_dev);
2025 		if (ret)
2026 			goto clk_free;
2027 		ret = stm32f7_i2c_write_fm_plus_bits(i2c_dev, true);
2028 		if (ret)
2029 			goto clk_free;
2030 	}
2031 
2032 	adap = &i2c_dev->adap;
2033 	i2c_set_adapdata(adap, i2c_dev);
2034 	snprintf(adap->name, sizeof(adap->name), "STM32F7 I2C(%pa)",
2035 		 &res->start);
2036 	adap->owner = THIS_MODULE;
2037 	adap->timeout = 2 * HZ;
2038 	adap->retries = 3;
2039 	adap->algo = &stm32f7_i2c_algo;
2040 	adap->dev.parent = &pdev->dev;
2041 	adap->dev.of_node = pdev->dev.of_node;
2042 
2043 	init_completion(&i2c_dev->complete);
2044 
2045 	/* Init DMA config if supported */
2046 	i2c_dev->dma = stm32_i2c_dma_request(i2c_dev->dev, phy_addr,
2047 					     STM32F7_I2C_TXDR,
2048 					     STM32F7_I2C_RXDR);
2049 	if (PTR_ERR(i2c_dev->dma) == -ENODEV)
2050 		i2c_dev->dma = NULL;
2051 	else if (IS_ERR(i2c_dev->dma)) {
2052 		ret = PTR_ERR(i2c_dev->dma);
2053 		if (ret != -EPROBE_DEFER)
2054 			dev_err(&pdev->dev,
2055 				"Failed to request dma error %i\n", ret);
2056 		goto fmp_clear;
2057 	}
2058 
2059 	if (i2c_dev->wakeup_src) {
2060 		device_set_wakeup_capable(i2c_dev->dev, true);
2061 
2062 		ret = dev_pm_set_wake_irq(i2c_dev->dev, irq_event);
2063 		if (ret) {
2064 			dev_err(i2c_dev->dev, "Failed to set wake up irq\n");
2065 			goto clr_wakeup_capable;
2066 		}
2067 	}
2068 
2069 	platform_set_drvdata(pdev, i2c_dev);
2070 
2071 	pm_runtime_set_autosuspend_delay(i2c_dev->dev,
2072 					 STM32F7_AUTOSUSPEND_DELAY);
2073 	pm_runtime_use_autosuspend(i2c_dev->dev);
2074 	pm_runtime_set_active(i2c_dev->dev);
2075 	pm_runtime_enable(i2c_dev->dev);
2076 
2077 	pm_runtime_get_noresume(&pdev->dev);
2078 
2079 	stm32f7_i2c_hw_config(i2c_dev);
2080 
2081 	ret = i2c_add_adapter(adap);
2082 	if (ret)
2083 		goto pm_disable;
2084 
2085 	dev_info(i2c_dev->dev, "STM32F7 I2C-%d bus adapter\n", adap->nr);
2086 
2087 	pm_runtime_mark_last_busy(i2c_dev->dev);
2088 	pm_runtime_put_autosuspend(i2c_dev->dev);
2089 
2090 	return 0;
2091 
2092 pm_disable:
2093 	pm_runtime_put_noidle(i2c_dev->dev);
2094 	pm_runtime_disable(i2c_dev->dev);
2095 	pm_runtime_set_suspended(i2c_dev->dev);
2096 	pm_runtime_dont_use_autosuspend(i2c_dev->dev);
2097 
2098 	if (i2c_dev->wakeup_src)
2099 		dev_pm_clear_wake_irq(i2c_dev->dev);
2100 
2101 clr_wakeup_capable:
2102 	if (i2c_dev->wakeup_src)
2103 		device_set_wakeup_capable(i2c_dev->dev, false);
2104 
2105 	if (i2c_dev->dma) {
2106 		stm32_i2c_dma_free(i2c_dev->dma);
2107 		i2c_dev->dma = NULL;
2108 	}
2109 
2110 fmp_clear:
2111 	stm32f7_i2c_write_fm_plus_bits(i2c_dev, false);
2112 
2113 clk_free:
2114 	clk_disable_unprepare(i2c_dev->clk);
2115 
2116 	return ret;
2117 }
2118 
2119 static int stm32f7_i2c_remove(struct platform_device *pdev)
2120 {
2121 	struct stm32f7_i2c_dev *i2c_dev = platform_get_drvdata(pdev);
2122 
2123 	i2c_del_adapter(&i2c_dev->adap);
2124 	pm_runtime_get_sync(i2c_dev->dev);
2125 
2126 	if (i2c_dev->wakeup_src) {
2127 		dev_pm_clear_wake_irq(i2c_dev->dev);
2128 		/*
2129 		 * enforce that wakeup is disabled and that the device
2130 		 * is marked as non wakeup capable
2131 		 */
2132 		device_init_wakeup(i2c_dev->dev, false);
2133 	}
2134 
2135 	pm_runtime_put_noidle(i2c_dev->dev);
2136 	pm_runtime_disable(i2c_dev->dev);
2137 	pm_runtime_set_suspended(i2c_dev->dev);
2138 	pm_runtime_dont_use_autosuspend(i2c_dev->dev);
2139 
2140 	if (i2c_dev->dma) {
2141 		stm32_i2c_dma_free(i2c_dev->dma);
2142 		i2c_dev->dma = NULL;
2143 	}
2144 
2145 	stm32f7_i2c_write_fm_plus_bits(i2c_dev, false);
2146 
2147 	clk_disable_unprepare(i2c_dev->clk);
2148 
2149 	return 0;
2150 }
2151 
2152 static int __maybe_unused stm32f7_i2c_runtime_suspend(struct device *dev)
2153 {
2154 	struct stm32f7_i2c_dev *i2c_dev = dev_get_drvdata(dev);
2155 
2156 	if (!stm32f7_i2c_is_slave_registered(i2c_dev))
2157 		clk_disable_unprepare(i2c_dev->clk);
2158 
2159 	return 0;
2160 }
2161 
2162 static int __maybe_unused stm32f7_i2c_runtime_resume(struct device *dev)
2163 {
2164 	struct stm32f7_i2c_dev *i2c_dev = dev_get_drvdata(dev);
2165 	int ret;
2166 
2167 	if (!stm32f7_i2c_is_slave_registered(i2c_dev)) {
2168 		ret = clk_prepare_enable(i2c_dev->clk);
2169 		if (ret) {
2170 			dev_err(dev, "failed to prepare_enable clock\n");
2171 			return ret;
2172 		}
2173 	}
2174 
2175 	return 0;
2176 }
2177 
2178 #ifdef CONFIG_PM_SLEEP
2179 static int stm32f7_i2c_regs_backup(struct stm32f7_i2c_dev *i2c_dev)
2180 {
2181 	int ret;
2182 	struct stm32f7_i2c_regs *backup_regs = &i2c_dev->backup_regs;
2183 
2184 	ret = pm_runtime_get_sync(i2c_dev->dev);
2185 	if (ret < 0)
2186 		return ret;
2187 
2188 	backup_regs->cr1 = readl_relaxed(i2c_dev->base + STM32F7_I2C_CR1);
2189 	backup_regs->cr2 = readl_relaxed(i2c_dev->base + STM32F7_I2C_CR2);
2190 	backup_regs->oar1 = readl_relaxed(i2c_dev->base + STM32F7_I2C_OAR1);
2191 	backup_regs->oar2 = readl_relaxed(i2c_dev->base + STM32F7_I2C_OAR2);
2192 	backup_regs->tmgr = readl_relaxed(i2c_dev->base + STM32F7_I2C_TIMINGR);
2193 	stm32f7_i2c_write_fm_plus_bits(i2c_dev, false);
2194 
2195 	pm_runtime_put_sync(i2c_dev->dev);
2196 
2197 	return ret;
2198 }
2199 
2200 static int stm32f7_i2c_regs_restore(struct stm32f7_i2c_dev *i2c_dev)
2201 {
2202 	u32 cr1;
2203 	int ret;
2204 	struct stm32f7_i2c_regs *backup_regs = &i2c_dev->backup_regs;
2205 
2206 	ret = pm_runtime_get_sync(i2c_dev->dev);
2207 	if (ret < 0)
2208 		return ret;
2209 
2210 	cr1 = readl_relaxed(i2c_dev->base + STM32F7_I2C_CR1);
2211 	if (cr1 & STM32F7_I2C_CR1_PE)
2212 		stm32f7_i2c_clr_bits(i2c_dev->base + STM32F7_I2C_CR1,
2213 				     STM32F7_I2C_CR1_PE);
2214 
2215 	writel_relaxed(backup_regs->tmgr, i2c_dev->base + STM32F7_I2C_TIMINGR);
2216 	writel_relaxed(backup_regs->cr1 & ~STM32F7_I2C_CR1_PE,
2217 		       i2c_dev->base + STM32F7_I2C_CR1);
2218 	if (backup_regs->cr1 & STM32F7_I2C_CR1_PE)
2219 		stm32f7_i2c_set_bits(i2c_dev->base + STM32F7_I2C_CR1,
2220 				     STM32F7_I2C_CR1_PE);
2221 	writel_relaxed(backup_regs->cr2, i2c_dev->base + STM32F7_I2C_CR2);
2222 	writel_relaxed(backup_regs->oar1, i2c_dev->base + STM32F7_I2C_OAR1);
2223 	writel_relaxed(backup_regs->oar2, i2c_dev->base + STM32F7_I2C_OAR2);
2224 	stm32f7_i2c_write_fm_plus_bits(i2c_dev, true);
2225 
2226 	pm_runtime_put_sync(i2c_dev->dev);
2227 
2228 	return ret;
2229 }
2230 
2231 static int stm32f7_i2c_suspend(struct device *dev)
2232 {
2233 	struct stm32f7_i2c_dev *i2c_dev = dev_get_drvdata(dev);
2234 	int ret;
2235 
2236 	i2c_mark_adapter_suspended(&i2c_dev->adap);
2237 
2238 	if (!device_may_wakeup(dev) && !dev->power.wakeup_path) {
2239 		ret = stm32f7_i2c_regs_backup(i2c_dev);
2240 		if (ret < 0) {
2241 			i2c_mark_adapter_resumed(&i2c_dev->adap);
2242 			return ret;
2243 		}
2244 
2245 		pinctrl_pm_select_sleep_state(dev);
2246 		pm_runtime_force_suspend(dev);
2247 	}
2248 
2249 	return 0;
2250 }
2251 
2252 static int stm32f7_i2c_resume(struct device *dev)
2253 {
2254 	struct stm32f7_i2c_dev *i2c_dev = dev_get_drvdata(dev);
2255 	int ret;
2256 
2257 	if (!device_may_wakeup(dev) && !dev->power.wakeup_path) {
2258 		ret = pm_runtime_force_resume(dev);
2259 		if (ret < 0)
2260 			return ret;
2261 		pinctrl_pm_select_default_state(dev);
2262 
2263 		ret = stm32f7_i2c_regs_restore(i2c_dev);
2264 		if (ret < 0)
2265 			return ret;
2266 	}
2267 
2268 	i2c_mark_adapter_resumed(&i2c_dev->adap);
2269 
2270 	return 0;
2271 }
2272 #endif
2273 
2274 static const struct dev_pm_ops stm32f7_i2c_pm_ops = {
2275 	SET_RUNTIME_PM_OPS(stm32f7_i2c_runtime_suspend,
2276 			   stm32f7_i2c_runtime_resume, NULL)
2277 	SET_SYSTEM_SLEEP_PM_OPS(stm32f7_i2c_suspend, stm32f7_i2c_resume)
2278 };
2279 
2280 static const struct of_device_id stm32f7_i2c_match[] = {
2281 	{ .compatible = "st,stm32f7-i2c", .data = &stm32f7_setup},
2282 	{ .compatible = "st,stm32mp15-i2c", .data = &stm32mp15_setup},
2283 	{},
2284 };
2285 MODULE_DEVICE_TABLE(of, stm32f7_i2c_match);
2286 
2287 static struct platform_driver stm32f7_i2c_driver = {
2288 	.driver = {
2289 		.name = "stm32f7-i2c",
2290 		.of_match_table = stm32f7_i2c_match,
2291 		.pm = &stm32f7_i2c_pm_ops,
2292 	},
2293 	.probe = stm32f7_i2c_probe,
2294 	.remove = stm32f7_i2c_remove,
2295 };
2296 
2297 module_platform_driver(stm32f7_i2c_driver);
2298 
2299 MODULE_AUTHOR("M'boumba Cedric Madianga <cedric.madianga@gmail.com>");
2300 MODULE_DESCRIPTION("STMicroelectronics STM32F7 I2C driver");
2301 MODULE_LICENSE("GPL v2");
2302