xref: /optee_os/core/drivers/stm32_i2c.c (revision 717f942aebec6d7b7601b197b456fe20be914ef4)
1 // SPDX-License-Identifier: (GPL-2.0 OR BSD-3-Clause)
2 /*
3  * Copyright (c) 2017-2019, STMicroelectronics
4  *
5  * The driver API is defined in header file stm32_i2c.h.
6  *
7  * I2C bus driver does not register to the PM framework. It is the
8  * responsibility of the bus owner to call the related STM32 I2C driver
9  * API functions when bus suspends or resumes.
10  */
11 
12 #include <arm.h>
13 #include <drivers/stm32_i2c.h>
14 #include <io.h>
15 #include <kernel/delay.h>
16 #include <kernel/dt.h>
17 #include <kernel/boot.h>
18 #include <kernel/panic.h>
19 #include <libfdt.h>
20 #include <stdbool.h>
21 #include <stdlib.h>
22 #include <stm32_util.h>
23 #include <trace.h>
24 
25 /* STM32 I2C registers offsets */
26 #define I2C_CR1				0x00U
27 #define I2C_CR2				0x04U
28 #define I2C_OAR1			0x08U
29 #define I2C_OAR2			0x0CU
30 #define I2C_TIMINGR			0x10U
31 #define I2C_TIMEOUTR			0x14U
32 #define I2C_ISR				0x18U
33 #define I2C_ICR				0x1CU
34 #define I2C_PECR			0x20U
35 #define I2C_RXDR			0x24U
36 #define I2C_TXDR			0x28U
37 #define I2C_SIZE			0x2CU
38 
39 /* Bit definition for I2C_CR1 register */
40 #define I2C_CR1_PE			BIT(0)
41 #define I2C_CR1_TXIE			BIT(1)
42 #define I2C_CR1_RXIE			BIT(2)
43 #define I2C_CR1_ADDRIE			BIT(3)
44 #define I2C_CR1_NACKIE			BIT(4)
45 #define I2C_CR1_STOPIE			BIT(5)
46 #define I2C_CR1_TCIE			BIT(6)
47 #define I2C_CR1_ERRIE			BIT(7)
48 #define I2C_CR1_DNF			GENMASK_32(11, 8)
49 #define I2C_CR1_ANFOFF			BIT(12)
50 #define I2C_CR1_SWRST			BIT(13)
51 #define I2C_CR1_TXDMAEN			BIT(14)
52 #define I2C_CR1_RXDMAEN			BIT(15)
53 #define I2C_CR1_SBC			BIT(16)
54 #define I2C_CR1_NOSTRETCH		BIT(17)
55 #define I2C_CR1_WUPEN			BIT(18)
56 #define I2C_CR1_GCEN			BIT(19)
57 #define I2C_CR1_SMBHEN			BIT(22)
58 #define I2C_CR1_SMBDEN			BIT(21)
59 #define I2C_CR1_ALERTEN			BIT(22)
60 #define I2C_CR1_PECEN			BIT(23)
61 
62 /* Bit definition for I2C_CR2 register */
63 #define I2C_CR2_SADD			GENMASK_32(9, 0)
64 #define I2C_CR2_RD_WRN			BIT(10)
65 #define I2C_CR2_RD_WRN_OFFSET		10U
66 #define I2C_CR2_ADD10			BIT(11)
67 #define I2C_CR2_HEAD10R			BIT(12)
68 #define I2C_CR2_START			BIT(13)
69 #define I2C_CR2_STOP			BIT(14)
70 #define I2C_CR2_NACK			BIT(15)
71 #define I2C_CR2_NBYTES			GENMASK_32(23, 16)
72 #define I2C_CR2_NBYTES_OFFSET		16U
73 #define I2C_CR2_RELOAD			BIT(24)
74 #define I2C_CR2_AUTOEND			BIT(25)
75 #define I2C_CR2_PECBYTE			BIT(26)
76 
77 /* Bit definition for I2C_OAR1 register */
78 #define I2C_OAR1_OA1			GENMASK_32(9, 0)
79 #define I2C_OAR1_OA1MODE		BIT(10)
80 #define I2C_OAR1_OA1EN			BIT(15)
81 
82 /* Bit definition for I2C_OAR2 register */
83 #define I2C_OAR2_OA2			GENMASK_32(7, 1)
84 #define I2C_OAR2_OA2MSK			GENMASK_32(10, 8)
85 #define I2C_OAR2_OA2NOMASK		0
86 #define I2C_OAR2_OA2MASK01		BIT(8)
87 #define I2C_OAR2_OA2MASK02		BIT(9)
88 #define I2C_OAR2_OA2MASK03		GENMASK_32(9, 8)
89 #define I2C_OAR2_OA2MASK04		BIT(10)
90 #define I2C_OAR2_OA2MASK05		(BIT(8) | BIT(10))
91 #define I2C_OAR2_OA2MASK06		(BIT(9) | BIT(10))
92 #define I2C_OAR2_OA2MASK07		GENMASK_32(10, 8)
93 #define I2C_OAR2_OA2EN			BIT(15)
94 
95 /* Bit definition for I2C_TIMINGR register */
96 #define I2C_TIMINGR_SCLL		GENMASK_32(7, 0)
97 #define I2C_TIMINGR_SCLH		GENMASK_32(15, 8)
98 #define I2C_TIMINGR_SDADEL		GENMASK_32(19, 16)
99 #define I2C_TIMINGR_SCLDEL		GENMASK_32(23, 20)
100 #define I2C_TIMINGR_PRESC		GENMASK_32(31, 28)
101 #define I2C_TIMINGR_SCLL_MAX		(I2C_TIMINGR_SCLL + 1)
102 #define I2C_TIMINGR_SCLH_MAX		((I2C_TIMINGR_SCLH >> 8) + 1)
103 #define I2C_TIMINGR_SDADEL_MAX		((I2C_TIMINGR_SDADEL >> 16) + 1)
104 #define I2C_TIMINGR_SCLDEL_MAX		((I2C_TIMINGR_SCLDEL >> 20) + 1)
105 #define I2C_TIMINGR_PRESC_MAX		((I2C_TIMINGR_PRESC >> 28) + 1)
106 #define I2C_SET_TIMINGR_SCLL(n)		((n) & \
107 					 (I2C_TIMINGR_SCLL_MAX - 1))
108 #define I2C_SET_TIMINGR_SCLH(n)		(((n) & \
109 					  (I2C_TIMINGR_SCLH_MAX - 1)) << 8)
110 #define I2C_SET_TIMINGR_SDADEL(n)	(((n) & \
111 					  (I2C_TIMINGR_SDADEL_MAX - 1)) << 16)
112 #define I2C_SET_TIMINGR_SCLDEL(n)	(((n) & \
113 					  (I2C_TIMINGR_SCLDEL_MAX - 1)) << 20)
114 #define I2C_SET_TIMINGR_PRESC(n)	(((n) & \
115 					  (I2C_TIMINGR_PRESC_MAX - 1)) << 28)
116 
117 /* Bit definition for I2C_TIMEOUTR register */
118 #define I2C_TIMEOUTR_TIMEOUTA		GENMASK_32(11, 0)
119 #define I2C_TIMEOUTR_TIDLE		BIT(12)
120 #define I2C_TIMEOUTR_TIMOUTEN		BIT(15)
121 #define I2C_TIMEOUTR_TIMEOUTB		GENMASK_32(27, 16)
122 #define I2C_TIMEOUTR_TEXTEN		BIT(31)
123 
124 /* Bit definition for I2C_ISR register */
125 #define I2C_ISR_TXE			BIT(0)
126 #define I2C_ISR_TXIS			BIT(1)
127 #define I2C_ISR_RXNE			BIT(2)
128 #define I2C_ISR_ADDR			BIT(3)
129 #define I2C_ISR_NACKF			BIT(4)
130 #define I2C_ISR_STOPF			BIT(5)
131 #define I2C_ISR_TC			BIT(6)
132 #define I2C_ISR_TCR			BIT(7)
133 #define I2C_ISR_BERR			BIT(8)
134 #define I2C_ISR_ARLO			BIT(9)
135 #define I2C_ISR_OVR			BIT(10)
136 #define I2C_ISR_PECERR			BIT(11)
137 #define I2C_ISR_TIMEOUT			BIT(12)
138 #define I2C_ISR_ALERT			BIT(13)
139 #define I2C_ISR_BUSY			BIT(15)
140 #define I2C_ISR_DIR			BIT(16)
141 #define I2C_ISR_ADDCODE			GENMASK_32(23, 17)
142 
143 /* Bit definition for I2C_ICR register */
144 #define I2C_ICR_ADDRCF			BIT(3)
145 #define I2C_ICR_NACKCF			BIT(4)
146 #define I2C_ICR_STOPCF			BIT(5)
147 #define I2C_ICR_BERRCF			BIT(8)
148 #define I2C_ICR_ARLOCF			BIT(9)
149 #define I2C_ICR_OVRCF			BIT(10)
150 #define I2C_ICR_PECCF			BIT(11)
151 #define I2C_ICR_TIMOUTCF		BIT(12)
152 #define I2C_ICR_ALERTCF			BIT(13)
153 
154 /* Max data size for a single I2C transfer */
155 #define MAX_NBYTE_SIZE			255U
156 
157 #define I2C_NSEC_PER_SEC		1000000000UL
158 #define I2C_TIMEOUT_BUSY_MS		25
159 #define I2C_TIMEOUT_BUSY_US		(I2C_TIMEOUT_BUSY_MS * 1000)
160 
161 #define CR2_RESET_MASK			(I2C_CR2_SADD | I2C_CR2_HEAD10R | \
162 					 I2C_CR2_NBYTES | I2C_CR2_RELOAD | \
163 					 I2C_CR2_RD_WRN)
164 
165 #define TIMINGR_CLEAR_MASK		(I2C_TIMINGR_SCLL | I2C_TIMINGR_SCLH | \
166 					 I2C_TIMINGR_SDADEL | \
167 					 I2C_TIMINGR_SCLDEL | I2C_TIMINGR_PRESC)
168 
169 /*
170  * I2C transfer modes
171  * I2C_RELOAD: Enable Reload mode
172  * I2C_AUTOEND_MODE: Enable automatic end mode
173  * I2C_SOFTEND_MODE: Enable software end mode
174  */
175 #define I2C_RELOAD_MODE				I2C_CR2_RELOAD
176 #define I2C_AUTOEND_MODE			I2C_CR2_AUTOEND
177 #define I2C_SOFTEND_MODE			0x0
178 
179 /*
180  * Start/restart/stop I2C transfer requests.
181  *
182  * I2C_NO_STARTSTOP: Don't Generate stop and start condition
183  * I2C_GENERATE_STOP: Generate stop condition (size should be set to 0)
184  * I2C_GENERATE_START_READ: Generate Restart for read request.
185  * I2C_GENERATE_START_WRITE: Generate Restart for write request
186  */
187 #define I2C_NO_STARTSTOP			0x0
188 #define I2C_GENERATE_STOP			(BIT(31) | I2C_CR2_STOP)
189 #define I2C_GENERATE_START_READ			(BIT(31) | I2C_CR2_START | \
190 						 I2C_CR2_RD_WRN)
191 #define I2C_GENERATE_START_WRITE		(BIT(31) | I2C_CR2_START)
192 
193 /* Memory address byte sizes */
194 #define I2C_MEMADD_SIZE_8BIT		1
195 #define I2C_MEMADD_SIZE_16BIT		2
196 
197 /* Effective rate cannot be lower than 80% target rate */
198 #define RATE_MIN(rate)			(((rate) * 80U) / 100U)
199 
200 /*
201  * struct i2c_spec_s - Private I2C timing specifications.
202  * @rate: I2C bus speed (Hz)
203  * @fall_max: Max fall time of both SDA and SCL signals (ns)
204  * @rise_max: Max rise time of both SDA and SCL signals (ns)
205  * @hddat_min: Min data hold time (ns)
206  * @vddat_max: Max data valid time (ns)
207  * @sudat_min: Min data setup time (ns)
208  * @l_min: Min low period of the SCL clock (ns)
209  * @h_min: Min high period of the SCL clock (ns)
210  */
211 struct i2c_spec_s {
212 	uint32_t rate;
213 	uint32_t fall_max;
214 	uint32_t rise_max;
215 	uint32_t hddat_min;
216 	uint32_t vddat_max;
217 	uint32_t sudat_min;
218 	uint32_t l_min;
219 	uint32_t h_min;
220 };
221 
222 /*
223  * struct i2c_timing_s - Private I2C output parameters.
224  * @scldel: Data setup time
225  * @sdadel: Data hold time
226  * @sclh: SCL high period (master mode)
227  * @sclh: SCL low period (master mode)
228  * @is_saved: True if relating to a configuration candidate
229  */
230 struct i2c_timing_s {
231 	uint8_t scldel;
232 	uint8_t sdadel;
233 	uint8_t sclh;
234 	uint8_t scll;
235 	bool is_saved;
236 };
237 
238 /* This table must be sorted in increasing value for field @rate */
239 static const struct i2c_spec_s i2c_specs[] = {
240 	/* Standard - 100KHz */
241 	{
242 		.rate = I2C_STANDARD_RATE,
243 		.fall_max = 300,
244 		.rise_max = 1000,
245 		.hddat_min = 0,
246 		.vddat_max = 3450,
247 		.sudat_min = 250,
248 		.l_min = 4700,
249 		.h_min = 4000,
250 	},
251 	/* Fast - 400KHz */
252 	{
253 		.rate = I2C_FAST_RATE,
254 		.fall_max = 300,
255 		.rise_max = 300,
256 		.hddat_min = 0,
257 		.vddat_max = 900,
258 		.sudat_min = 100,
259 		.l_min = 1300,
260 		.h_min = 600,
261 	},
262 	/* FastPlus - 1MHz */
263 	{
264 		.rate = I2C_FAST_PLUS_RATE,
265 		.fall_max = 100,
266 		.rise_max = 120,
267 		.hddat_min = 0,
268 		.vddat_max = 450,
269 		.sudat_min = 50,
270 		.l_min = 500,
271 		.h_min = 260,
272 	},
273 };
274 
275 /*
276  * I2C request parameters
277  * @dev_addr: I2C address of the target device
278  * @mode: Communication mode, one of I2C_MODE_(MASTER|MEM)
279  * @mem_addr: Target memory cell accessed in device (memory mode)
280  * @mem_addr_size: Byte size of the memory cell address (memory mode)
281  * @timeout_ms: Timeout in millisenconds for the request
282  */
283 struct i2c_request {
284 	uint32_t dev_addr;
285 	enum i2c_mode_e mode;
286 	uint32_t mem_addr;
287 	uint32_t mem_addr_size;
288 	unsigned int timeout_ms;
289 };
290 
291 static vaddr_t get_base(struct i2c_handle_s *hi2c)
292 {
293 	return io_pa_or_va_secure(&hi2c->base, hi2c->reg_size);
294 }
295 
296 static void notif_i2c_timeout(struct i2c_handle_s *hi2c)
297 {
298 	hi2c->i2c_err |= I2C_ERROR_TIMEOUT;
299 	hi2c->i2c_state = I2C_STATE_READY;
300 }
301 
302 static const struct i2c_spec_s *get_specs(uint32_t rate)
303 {
304 	size_t i = 0;
305 
306 	for (i = 0; i < ARRAY_SIZE(i2c_specs); i++)
307 		if (rate <= i2c_specs[i].rate)
308 			return i2c_specs + i;
309 
310 	return NULL;
311 }
312 
313 static void save_cfg(struct i2c_handle_s *hi2c, struct i2c_cfg *cfg)
314 {
315 	vaddr_t base = get_base(hi2c);
316 
317 	stm32_clock_enable(hi2c->clock);
318 
319 	cfg->cr1 = io_read32(base + I2C_CR1);
320 	cfg->cr2 = io_read32(base + I2C_CR2);
321 	cfg->oar1 = io_read32(base + I2C_OAR1);
322 	cfg->oar2 = io_read32(base + I2C_OAR2);
323 	cfg->timingr = io_read32(base + I2C_TIMINGR);
324 
325 	stm32_clock_disable(hi2c->clock);
326 }
327 
328 static void restore_cfg(struct i2c_handle_s *hi2c, struct i2c_cfg *cfg)
329 {
330 	vaddr_t base = get_base(hi2c);
331 
332 	stm32_clock_enable(hi2c->clock);
333 
334 	io_clrbits32(base + I2C_CR1, I2C_CR1_PE);
335 	io_write32(base + I2C_TIMINGR, cfg->timingr & TIMINGR_CLEAR_MASK);
336 	io_write32(base + I2C_OAR1, cfg->oar1);
337 	io_write32(base + I2C_CR2, cfg->cr2);
338 	io_write32(base + I2C_OAR2, cfg->oar2);
339 	io_write32(base + I2C_CR1, cfg->cr1 & ~I2C_CR1_PE);
340 	io_setbits32(base + I2C_CR1, cfg->cr1 & I2C_CR1_PE);
341 
342 	stm32_clock_disable(hi2c->clock);
343 }
344 
345 static void __maybe_unused dump_cfg(struct i2c_cfg *cfg __maybe_unused)
346 {
347 	DMSG("CR1:  %#"PRIx32, cfg->cr1);
348 	DMSG("CR2:  %#"PRIx32, cfg->cr2);
349 	DMSG("OAR1: %#"PRIx32, cfg->oar1);
350 	DMSG("OAR2: %#"PRIx32, cfg->oar2);
351 	DMSG("TIM:  %#"PRIx32, cfg->timingr);
352 }
353 
354 static void __maybe_unused dump_i2c(struct i2c_handle_s *hi2c)
355 {
356 	vaddr_t __maybe_unused base = get_base(hi2c);
357 
358 	stm32_clock_enable(hi2c->clock);
359 
360 	DMSG("CR1:  %#"PRIx32, io_read32(base + I2C_CR1));
361 	DMSG("CR2:  %#"PRIx32, io_read32(base + I2C_CR2));
362 	DMSG("OAR1: %#"PRIx32, io_read32(base + I2C_OAR1));
363 	DMSG("OAR2: %#"PRIx32, io_read32(base + I2C_OAR2));
364 	DMSG("TIM:  %#"PRIx32, io_read32(base + I2C_TIMINGR));
365 
366 	stm32_clock_disable(hi2c->clock);
367 }
368 
369 /*
370  * Compute the I2C device timings
371  *
372  * @init: Ref to the initialization configuration structure
373  * @clock_src: I2C clock source frequency (Hz)
374  * @timing: Pointer to the final computed timing result
375  * Return 0 on success or a negative value
376  */
377 static int i2c_compute_timing(struct stm32_i2c_init_s *init,
378 			      unsigned long clock_src, uint32_t *timing)
379 {
380 	const struct i2c_spec_s *specs = NULL;
381 	uint32_t speed_freq = 0;
382 	uint32_t i2cbus = UDIV_ROUND_NEAREST(I2C_NSEC_PER_SEC, speed_freq);
383 	uint32_t i2cclk = UDIV_ROUND_NEAREST(I2C_NSEC_PER_SEC, clock_src);
384 	uint32_t p_prev = I2C_TIMINGR_PRESC_MAX;
385 	uint32_t af_delay_min = 0;
386 	uint32_t af_delay_max = 0;
387 	uint32_t dnf_delay = 0;
388 	uint32_t tsync = 0;
389 	uint32_t clk_min = 0;
390 	uint32_t clk_max = 0;
391 	int clk_error_prev = 0;
392 	uint16_t p = 0;
393 	uint16_t l = 0;
394 	uint16_t a = 0;
395 	uint16_t h = 0;
396 	unsigned int sdadel_min = 0;
397 	unsigned int sdadel_max = 0;
398 	unsigned int scldel_min = 0;
399 	unsigned int delay = 0;
400 	int s = -1;
401 	struct i2c_timing_s solutions[I2C_TIMINGR_PRESC_MAX] = { 0 };
402 
403 	specs = get_specs(init->bus_rate);
404 	if (!specs) {
405 		DMSG("I2C speed out of bound: %"PRId32"Hz", init->bus_rate);
406 		return -1;
407 	}
408 
409 	speed_freq = specs->rate;
410 	i2cbus = UDIV_ROUND_NEAREST(I2C_NSEC_PER_SEC, speed_freq);
411 	clk_error_prev = INT_MAX;
412 
413 	if (init->rise_time > specs->rise_max ||
414 	    init->fall_time > specs->fall_max) {
415 		DMSG("I2C rise{%"PRId32">%"PRId32"}/fall{%"PRId32">%"PRId32"}",
416 		     init->rise_time, specs->rise_max,
417 		     init->fall_time, specs->fall_max);
418 		return -1;
419 	}
420 
421 	if (init->digital_filter_coef > STM32_I2C_DIGITAL_FILTER_MAX) {
422 		DMSG("DNF out of bound %"PRId8"/%d",
423 		     init->digital_filter_coef, STM32_I2C_DIGITAL_FILTER_MAX);
424 		return -1;
425 	}
426 
427 	/* Analog and Digital Filters */
428 	if (init->analog_filter) {
429 		af_delay_min = STM32_I2C_ANALOG_FILTER_DELAY_MIN;
430 		af_delay_max = STM32_I2C_ANALOG_FILTER_DELAY_MAX;
431 	}
432 	dnf_delay = init->digital_filter_coef * i2cclk;
433 
434 	sdadel_min = specs->hddat_min + init->fall_time;
435 	delay = af_delay_min - ((init->digital_filter_coef + 3) * i2cclk);
436 	if (SUB_OVERFLOW(sdadel_min, delay, &sdadel_min))
437 		sdadel_min = 0;
438 
439 	sdadel_max = specs->vddat_max - init->rise_time;
440 	delay = af_delay_max - ((init->digital_filter_coef + 4) * i2cclk);
441 	if (SUB_OVERFLOW(sdadel_max, delay, &sdadel_max))
442 		sdadel_max = 0;
443 
444 	scldel_min = init->rise_time + specs->sudat_min;
445 
446 	DMSG("I2C SDADEL(min/max): %u/%u, SCLDEL(Min): %u",
447 	     sdadel_min, sdadel_max, scldel_min);
448 
449 	/* Compute possible values for PRESC, SCLDEL and SDADEL */
450 	for (p = 0; p < I2C_TIMINGR_PRESC_MAX; p++) {
451 		for (l = 0; l < I2C_TIMINGR_SCLDEL_MAX; l++) {
452 			uint32_t scldel = (l + 1) * (p + 1) * i2cclk;
453 
454 			if (scldel < scldel_min)
455 				continue;
456 
457 			for (a = 0; a < I2C_TIMINGR_SDADEL_MAX; a++) {
458 				uint32_t sdadel = (a * (p + 1) + 1) * i2cclk;
459 
460 				if ((sdadel >= sdadel_min) &&
461 				    (sdadel <= sdadel_max) &&
462 				    (p != p_prev)) {
463 					solutions[p].scldel = l;
464 					solutions[p].sdadel = a;
465 					solutions[p].is_saved = true;
466 					p_prev = p;
467 					break;
468 				}
469 			}
470 
471 			if (p_prev == p)
472 				break;
473 		}
474 	}
475 
476 	if (p_prev == I2C_TIMINGR_PRESC_MAX) {
477 		DMSG("I2C no Prescaler solution");
478 		return -1;
479 	}
480 
481 	tsync = af_delay_min + dnf_delay + (2 * i2cclk);
482 	clk_max = I2C_NSEC_PER_SEC / RATE_MIN(specs->rate);
483 	clk_min = I2C_NSEC_PER_SEC / specs->rate;
484 
485 	/*
486 	 * Among prescaler possibilities discovered above figures out SCL Low
487 	 * and High Period. Provided:
488 	 * - SCL Low Period has to be higher than Low Period of the SCL Clock
489 	 *   defined by I2C Specification. I2C Clock has to be lower than
490 	 *   (SCL Low Period - Analog/Digital filters) / 4.
491 	 * - SCL High Period has to be lower than High Period of the SCL Clock
492 	 *   defined by I2C Specification.
493 	 * - I2C Clock has to be lower than SCL High Period.
494 	 */
495 	for (p = 0; p < I2C_TIMINGR_PRESC_MAX; p++) {
496 		uint32_t prescaler = (p + 1) * i2cclk;
497 
498 		if (!solutions[p].is_saved)
499 			continue;
500 
501 		for (l = 0; l < I2C_TIMINGR_SCLL_MAX; l++) {
502 			uint32_t tscl_l = ((l + 1) * prescaler) + tsync;
503 
504 			if (tscl_l < specs->l_min ||
505 			    i2cclk >= ((tscl_l - af_delay_min - dnf_delay) / 4))
506 				continue;
507 
508 			for (h = 0; h < I2C_TIMINGR_SCLH_MAX; h++) {
509 				uint32_t tscl_h = ((h + 1) * prescaler) + tsync;
510 				uint32_t tscl = tscl_l + tscl_h +
511 						init->rise_time +
512 						init->fall_time;
513 
514 				if (tscl >= clk_min && tscl <= clk_max &&
515 				    tscl_h >= specs->h_min && i2cclk < tscl_h) {
516 					int clk_error = tscl - i2cbus;
517 
518 					if (clk_error < 0)
519 						clk_error = -clk_error;
520 
521 					if (clk_error < clk_error_prev) {
522 						clk_error_prev = clk_error;
523 						solutions[p].scll = l;
524 						solutions[p].sclh = h;
525 						s = p;
526 					}
527 				}
528 			}
529 		}
530 	}
531 
532 	if (s < 0) {
533 		DMSG("I2C no solution at all");
534 		return -1;
535 	}
536 
537 	/* Finalize timing settings */
538 	*timing = I2C_SET_TIMINGR_PRESC(s) |
539 		   I2C_SET_TIMINGR_SCLDEL(solutions[s].scldel) |
540 		   I2C_SET_TIMINGR_SDADEL(solutions[s].sdadel) |
541 		   I2C_SET_TIMINGR_SCLH(solutions[s].sclh) |
542 		   I2C_SET_TIMINGR_SCLL(solutions[s].scll);
543 
544 	DMSG("I2C TIMINGR (PRESC/SCLDEL/SDADEL): %i/%"PRIu8"/%"PRIu8,
545 	     s, solutions[s].scldel, solutions[s].sdadel);
546 	DMSG("I2C TIMINGR (SCLH/SCLL): %"PRIu8"/%"PRIu8,
547 	     solutions[s].sclh, solutions[s].scll);
548 	DMSG("I2C TIMINGR: 0x%"PRIx32, *timing);
549 
550 	return 0;
551 }
552 
553 /* i2c_specs[] must be sorted by increasing rate */
554 static bool __maybe_unused i2c_specs_is_consistent(void)
555 {
556 	size_t i = 0;
557 
558 	COMPILE_TIME_ASSERT(ARRAY_SIZE(i2c_specs));
559 
560 	for (i = 1; i < ARRAY_SIZE(i2c_specs); i++)
561 		if (i2c_specs[i - 1].rate >= i2c_specs[i].rate)
562 			return false;
563 
564 	return true;
565 }
566 
567 /*
568  * @brief  From requested rate, get the closest I2C rate without exceeding it,
569  *         within I2C specification values defined in @i2c_specs.
570  * @param  rate: The requested rate.
571  * @retval Found rate, else the lowest value supported by platform.
572  */
573 static uint32_t get_lower_rate(uint32_t rate)
574 {
575 	size_t i = 0;
576 
577 	for (i = ARRAY_SIZE(i2c_specs); i > 0; i--)
578 		if (rate > i2c_specs[i - 1].rate)
579 			return i2c_specs[i - 1].rate;
580 
581 	return i2c_specs[0].rate;
582 }
583 
584 /*
585  * Setup the I2C device timings
586  *
587  * @hi2c: I2C handle structure
588  * @init: Ref to the initialization configuration structure
589  * @timing: Output TIMINGR register configuration value
590  * @retval 0 if OK, negative value else
591  */
592 static int i2c_setup_timing(struct i2c_handle_s *hi2c,
593 			    struct stm32_i2c_init_s *init,
594 			    uint32_t *timing)
595 {
596 	int rc = 0;
597 	unsigned long clock_src = 0;
598 
599 	assert(i2c_specs_is_consistent());
600 
601 	clock_src = stm32_clock_get_rate(hi2c->clock);
602 	if (!clock_src) {
603 		DMSG("Null I2C clock rate");
604 		return -1;
605 	}
606 
607 	/*
608 	 * If the timing has already been computed, and the frequency is the
609 	 * same as when it was computed, then use the saved timing.
610 	 */
611 	if (clock_src == hi2c->saved_frequency) {
612 		*timing = hi2c->saved_timing;
613 		return 0;
614 	}
615 
616 	do {
617 		rc = i2c_compute_timing(init, clock_src, timing);
618 		if (rc) {
619 			DMSG("Failed to compute I2C timings");
620 			if (init->bus_rate > I2C_STANDARD_RATE) {
621 				init->bus_rate = get_lower_rate(init->bus_rate);
622 				IMSG("Downgrade I2C speed to %"PRIu32"Hz)",
623 				     init->bus_rate);
624 			} else {
625 				break;
626 			}
627 		}
628 	} while (rc);
629 
630 	if (rc) {
631 		DMSG("Impossible to compute I2C timings");
632 		return rc;
633 	}
634 
635 	DMSG("I2C Freq(%"PRIu32"Hz), Clk Source(%lu)",
636 	     init->bus_rate, clock_src);
637 	DMSG("I2C Rise(%"PRId32") and Fall(%"PRId32") Time",
638 	     init->rise_time, init->fall_time);
639 	DMSG("I2C Analog Filter(%s), DNF(%"PRIu8")",
640 	     init->analog_filter ? "On" : "Off", init->digital_filter_coef);
641 
642 	hi2c->saved_timing = *timing;
643 	hi2c->saved_frequency = clock_src;
644 
645 	return 0;
646 }
647 
648 /*
649  * Configure I2C Analog noise filter.
650  * @hi2c: I2C handle structure
651  * @analog_filter_on: True if enabling analog filter, false otherwise
652  * Return 0 on success or a negative value
653  */
654 static int i2c_config_analog_filter(struct i2c_handle_s *hi2c,
655 				    bool analog_filter_on)
656 {
657 	vaddr_t base = get_base(hi2c);
658 
659 	if (hi2c->i2c_state != I2C_STATE_READY)
660 		return -1;
661 
662 	hi2c->i2c_state = I2C_STATE_BUSY;
663 
664 	/* Disable the selected I2C peripheral */
665 	io_clrbits32(base + I2C_CR1, I2C_CR1_PE);
666 
667 	/* Reset I2Cx ANOFF bit */
668 	io_clrbits32(base + I2C_CR1, I2C_CR1_ANFOFF);
669 
670 	/* Set analog filter bit if filter is disabled */
671 	if (!analog_filter_on)
672 		io_setbits32(base + I2C_CR1, I2C_CR1_ANFOFF);
673 
674 	/* Enable the selected I2C peripheral */
675 	io_setbits32(base + I2C_CR1, I2C_CR1_PE);
676 
677 	hi2c->i2c_state = I2C_STATE_READY;
678 
679 	return 0;
680 }
681 
682 int stm32_i2c_get_setup_from_fdt(void *fdt, int node,
683 				 struct stm32_i2c_init_s *init,
684 				 struct stm32_pinctrl **pinctrl,
685 				 size_t *pinctrl_count)
686 {
687 	const fdt32_t *cuint = NULL;
688 	struct dt_node_info info = { .status = 0 };
689 	int count = 0;
690 
691 	/* Default STM32 specific configs caller may need to overwrite */
692 	memset(init, 0, sizeof(*init));
693 
694 	_fdt_fill_device_info(fdt, &info, node);
695 	assert(info.reg != DT_INFO_INVALID_REG &&
696 	       info.reg_size != DT_INFO_INVALID_REG_SIZE &&
697 	       info.clock != DT_INFO_INVALID_CLOCK);
698 
699 	init->dt_status = info.status;
700 	init->pbase = info.reg;
701 	init->reg_size = info.reg_size;
702 	init->clock = info.clock;
703 
704 	cuint = fdt_getprop(fdt, node, "i2c-scl-rising-time-ns", NULL);
705 	if (cuint)
706 		init->rise_time = fdt32_to_cpu(*cuint);
707 	else
708 		init->rise_time = STM32_I2C_RISE_TIME_DEFAULT;
709 
710 	cuint = fdt_getprop(fdt, node, "i2c-scl-falling-time-ns", NULL);
711 	if (cuint)
712 		init->fall_time = fdt32_to_cpu(*cuint);
713 	else
714 		init->fall_time = STM32_I2C_FALL_TIME_DEFAULT;
715 
716 	cuint = fdt_getprop(fdt, node, "clock-frequency", NULL);
717 	if (cuint) {
718 		init->bus_rate = fdt32_to_cpu(*cuint);
719 
720 		if (init->bus_rate > I2C_FAST_PLUS_RATE) {
721 			DMSG("Invalid bus speed (%"PRIu32" > %i)",
722 			     init->bus_rate, I2C_FAST_PLUS_RATE);
723 			return -FDT_ERR_BADVALUE;
724 		}
725 	} else {
726 		init->bus_rate = I2C_STANDARD_RATE;
727 	}
728 
729 	count = stm32_pinctrl_fdt_get_pinctrl(fdt, node, NULL, 0);
730 	if (count <= 0) {
731 		*pinctrl = NULL;
732 		*pinctrl_count = 0;
733 		return count;
734 	}
735 
736 	if (count > 2)
737 		panic("Too many PINCTRLs found");
738 
739 	*pinctrl = calloc(count, sizeof(**pinctrl));
740 	if (!*pinctrl)
741 		panic();
742 
743 	*pinctrl_count = stm32_pinctrl_fdt_get_pinctrl(fdt, node,
744 						       *pinctrl, count);
745 	assert(*pinctrl_count == (unsigned int)count);
746 
747 	return 0;
748 }
749 
750 int stm32_i2c_init(struct i2c_handle_s *hi2c,
751 		   struct stm32_i2c_init_s *init_data)
752 {
753 	int rc = 0;
754 	uint32_t timing = 0;
755 	vaddr_t base = 0;
756 	uint32_t val = 0;
757 
758 	hi2c->dt_status = init_data->dt_status;
759 	hi2c->base.pa = init_data->pbase;
760 	hi2c->reg_size = init_data->reg_size;
761 	hi2c->clock = init_data->clock;
762 
763 	rc = i2c_setup_timing(hi2c, init_data, &timing);
764 	if (rc)
765 		return rc;
766 
767 	stm32_clock_enable(hi2c->clock);
768 	base = get_base(hi2c);
769 	hi2c->i2c_state = I2C_STATE_BUSY;
770 
771 	/* Disable the selected I2C peripheral */
772 	io_clrbits32(base + I2C_CR1, I2C_CR1_PE);
773 
774 	/* Configure I2Cx: Frequency range */
775 	io_write32(base + I2C_TIMINGR, timing & TIMINGR_CLEAR_MASK);
776 
777 	/* Disable Own Address1 before set the Own Address1 configuration */
778 	io_write32(base + I2C_OAR1, 0);
779 
780 	/* Configure I2Cx: Own Address1 and ack own address1 mode */
781 	if (init_data->addr_mode_10b_not_7b)
782 		io_write32(base + I2C_OAR1,
783 			   I2C_OAR1_OA1EN | I2C_OAR1_OA1MODE |
784 			   init_data->own_address1);
785 	else
786 		io_write32(base + I2C_OAR1,
787 			   I2C_OAR1_OA1EN | init_data->own_address1);
788 
789 	/* Configure I2Cx: Addressing Master mode */
790 	io_write32(base + I2C_CR2, 0);
791 	if (init_data->addr_mode_10b_not_7b)
792 		io_setbits32(base + I2C_CR2, I2C_CR2_ADD10);
793 
794 	/*
795 	 * Enable the AUTOEND by default, and enable NACK
796 	 * (should be disabled only during Slave process).
797 	 */
798 	io_setbits32(base + I2C_CR2, I2C_CR2_AUTOEND | I2C_CR2_NACK);
799 
800 	/* Disable Own Address2 before set the Own Address2 configuration */
801 	io_write32(base + I2C_OAR2, 0);
802 
803 	/* Configure I2Cx: Dual mode and Own Address2 */
804 	if (init_data->dual_address_mode)
805 		io_write32(base + I2C_OAR2,
806 			   I2C_OAR2_OA2EN | init_data->own_address2 |
807 			   (init_data->own_address2_masks << 8));
808 
809 	/* Configure I2Cx: Generalcall and NoStretch mode */
810 	val = 0;
811 	if (init_data->general_call_mode)
812 		val |= I2C_CR1_GCEN;
813 	if (init_data->no_stretch_mode)
814 		val |= I2C_CR1_NOSTRETCH;
815 	io_write32(base + I2C_CR1, val);
816 
817 	/* Enable the selected I2C peripheral */
818 	io_setbits32(base + I2C_CR1, I2C_CR1_PE);
819 
820 	hi2c->i2c_err = I2C_ERROR_NONE;
821 	hi2c->i2c_state = I2C_STATE_READY;
822 
823 	rc = i2c_config_analog_filter(hi2c, init_data->analog_filter);
824 	if (rc)
825 		DMSG("I2C analog filter error %d", rc);
826 
827 	stm32_clock_disable(hi2c->clock);
828 
829 	return rc;
830 }
831 
832 /* I2C transmit (TX) data register flush sequence */
833 static void i2c_flush_txdr(struct i2c_handle_s *hi2c)
834 {
835 	vaddr_t base = get_base(hi2c);
836 
837 	/*
838 	 * If a pending TXIS flag is set,
839 	 * write a dummy data in TXDR to clear it.
840 	 */
841 	if (io_read32(base + I2C_ISR) & I2C_ISR_TXIS)
842 		io_write32(base + I2C_TXDR, 0);
843 
844 	/* Flush TX register if not empty */
845 	if ((io_read32(base + I2C_ISR) & I2C_ISR_TXE) == 0)
846 		io_setbits32(base + I2C_ISR, I2C_ISR_TXE);
847 }
848 
849 /*
850  * Wait for a single target I2C_ISR bit to reach an awaited value (0 or 1)
851  *
852  * @hi2c: I2C handle structure
853  * @bit_mask: Bit mask for the target single bit position to consider
854  * @awaited_value: Awaited value of the target bit in I2C_ISR, 0 or 1
855  * @timeout_ref: Expriation timeout reference
856  * Return 0 on success and a non-zero value on timeout
857  */
858 static int wait_isr_event(struct i2c_handle_s *hi2c, uint32_t bit_mask,
859 			  unsigned int awaited_value, uint64_t timeout_ref)
860 {
861 	vaddr_t isr = get_base(hi2c) + I2C_ISR;
862 
863 	assert(IS_POWER_OF_TWO(bit_mask) && !(awaited_value & ~1U));
864 
865 	/* May timeout while TEE thread is suspended */
866 	while (!timeout_elapsed(timeout_ref))
867 		if (!!(io_read32(isr) & bit_mask) == awaited_value)
868 			break;
869 
870 	if (!!(io_read32(isr) & bit_mask) == awaited_value)
871 		return 0;
872 
873 	notif_i2c_timeout(hi2c);
874 	return -1;
875 }
876 
877 /* Handle Acknowledge-Failed sequence detection during an I2C Communication */
878 static int i2c_ack_failed(struct i2c_handle_s *hi2c, uint64_t timeout_ref)
879 {
880 	vaddr_t base = get_base(hi2c);
881 
882 	if ((io_read32(base + I2C_ISR) & I2C_ISR_NACKF) == 0U)
883 		return 0;
884 
885 	/*
886 	 * Wait until STOP Flag is reset. Use polling method.
887 	 * AutoEnd should be initiate after AF.
888 	 * Timeout may elpased while TEE thread is suspended.
889 	 */
890 	while (!timeout_elapsed(timeout_ref))
891 		if (io_read32(base + I2C_ISR) & I2C_ISR_STOPF)
892 			break;
893 
894 	if ((io_read32(base + I2C_ISR) & I2C_ISR_STOPF) == 0) {
895 		notif_i2c_timeout(hi2c);
896 		return -1;
897 	}
898 
899 	io_write32(base + I2C_ICR, I2C_ISR_NACKF);
900 
901 	io_write32(base + I2C_ICR, I2C_ISR_STOPF);
902 
903 	i2c_flush_txdr(hi2c);
904 
905 	io_clrbits32(base + I2C_CR2, CR2_RESET_MASK);
906 
907 	hi2c->i2c_err |= I2C_ERROR_ACKF;
908 	hi2c->i2c_state = I2C_STATE_READY;
909 
910 	return -1;
911 }
912 
913 /* Wait TXIS bit is 1 in I2C_ISR register */
914 static int i2c_wait_txis(struct i2c_handle_s *hi2c, uint64_t timeout_ref)
915 {
916 	while (!timeout_elapsed(timeout_ref)) {
917 		if (io_read32(get_base(hi2c) + I2C_ISR) & I2C_ISR_TXIS)
918 			break;
919 		if (i2c_ack_failed(hi2c, timeout_ref))
920 			return -1;
921 	}
922 
923 	if (io_read32(get_base(hi2c) + I2C_ISR) & I2C_ISR_TXIS)
924 		return 0;
925 
926 	if (i2c_ack_failed(hi2c, timeout_ref))
927 		return -1;
928 
929 	notif_i2c_timeout(hi2c);
930 	return -1;
931 }
932 
933 /* Wait STOPF bit is 1 in I2C_ISR register */
934 static int i2c_wait_stop(struct i2c_handle_s *hi2c, uint64_t timeout_ref)
935 {
936 	while (!timeout_elapsed(timeout_ref)) {
937 		if (io_read32(get_base(hi2c) + I2C_ISR) & I2C_ISR_STOPF)
938 			break;
939 
940 		if (i2c_ack_failed(hi2c, timeout_ref))
941 			return -1;
942 	}
943 
944 	if (io_read32(get_base(hi2c) + I2C_ISR) & I2C_ISR_STOPF)
945 		return 0;
946 
947 	if (i2c_ack_failed(hi2c, timeout_ref))
948 		return -1;
949 
950 	notif_i2c_timeout(hi2c);
951 	return -1;
952 }
953 
954 /*
955  * Load I2C_CR2 register for a I2C transfer
956  *
957  * @hi2c: I2C handle structure
958  * @dev_addr: Slave address to be transferred
959  * @size: Number of bytes to be transferred
960  * @i2c_mode: One of I2C_{RELOAD|AUTOEND|SOFTEND}_MODE: Enable Reload mode.
961  * @startstop: One of I2C_NO_STARTSTOP, I2C_GENERATE_STOP,
962  *		I2C_GENERATE_START_{READ|WRITE}
963  */
964 static void i2c_transfer_config(struct i2c_handle_s *hi2c, uint32_t dev_addr,
965 				uint32_t size, uint32_t i2c_mode,
966 				uint32_t startstop)
967 {
968 	uint32_t clr_value = I2C_CR2_SADD | I2C_CR2_NBYTES | I2C_CR2_RELOAD |
969 			     I2C_CR2_AUTOEND | I2C_CR2_START | I2C_CR2_STOP |
970 			     (I2C_CR2_RD_WRN &
971 			      (startstop >> (31U - I2C_CR2_RD_WRN_OFFSET)));
972 	uint32_t set_value = (dev_addr & I2C_CR2_SADD) |
973 			     ((size << I2C_CR2_NBYTES_OFFSET) &
974 			      I2C_CR2_NBYTES) |
975 			     i2c_mode | startstop;
976 
977 	io_clrsetbits32(get_base(hi2c) + I2C_CR2, clr_value, set_value);
978 }
979 
980 /*
981  * Master sends target device address followed by internal memory
982  * address for a memory write request.
983  * Function returns 0 on success or a negative value.
984  */
985 static int i2c_request_mem_write(struct i2c_handle_s *hi2c,
986 				 struct i2c_request *request,
987 				 uint64_t timeout_ref)
988 {
989 	vaddr_t base = get_base(hi2c);
990 
991 	i2c_transfer_config(hi2c, request->dev_addr, request->mem_addr_size,
992 			    I2C_RELOAD_MODE, I2C_GENERATE_START_WRITE);
993 
994 	if (i2c_wait_txis(hi2c, timeout_ref))
995 		return -1;
996 
997 	if (request->mem_addr_size == I2C_MEMADD_SIZE_8BIT) {
998 		/* Send memory address */
999 		io_write8(base + I2C_TXDR, request->mem_addr & 0x00FFU);
1000 	} else {
1001 		/* Send MSB of memory address */
1002 		io_write8(base + I2C_TXDR, (request->mem_addr & 0xFF00U) >> 8);
1003 
1004 		if (i2c_wait_txis(hi2c, timeout_ref))
1005 			return -1;
1006 
1007 		/* Send LSB of memory address */
1008 		io_write8(base + I2C_TXDR, request->mem_addr & 0x00FFU);
1009 	}
1010 
1011 	if (wait_isr_event(hi2c, I2C_ISR_TCR, 1, timeout_ref))
1012 		return -1;
1013 
1014 	return 0;
1015 }
1016 
1017 /*
1018  * Master sends target device address followed by internal memory
1019  * address to prepare a memory read request.
1020  * Function returns 0 on success or a negative value.
1021  */
1022 static int i2c_request_mem_read(struct i2c_handle_s *hi2c,
1023 				struct i2c_request *request,
1024 				uint64_t timeout_ref)
1025 {
1026 	vaddr_t base = get_base(hi2c);
1027 
1028 	i2c_transfer_config(hi2c, request->dev_addr, request->mem_addr_size,
1029 			    I2C_SOFTEND_MODE, I2C_GENERATE_START_WRITE);
1030 
1031 	if (i2c_wait_txis(hi2c, timeout_ref))
1032 		return -1;
1033 
1034 	if (request->mem_addr_size == I2C_MEMADD_SIZE_8BIT) {
1035 		/* Send memory address */
1036 		io_write8(base + I2C_TXDR, request->mem_addr & 0x00FFU);
1037 	} else {
1038 		/* Send MSB of memory address */
1039 		io_write8(base + I2C_TXDR, (request->mem_addr & 0xFF00U) >> 8);
1040 
1041 		if (i2c_wait_txis(hi2c, timeout_ref))
1042 			return -1;
1043 
1044 		/* Send LSB of memory address */
1045 		io_write8(base + I2C_TXDR, request->mem_addr & 0x00FFU);
1046 	}
1047 
1048 	if (wait_isr_event(hi2c, I2C_ISR_TC, 1, timeout_ref))
1049 		return -1;
1050 
1051 	return 0;
1052 }
1053 
1054 /*
1055  * Write an amount of data in blocking mode
1056  *
1057  * @hi2c: Reference to struct i2c_handle_s
1058  * @request: I2C request parameters
1059  * @p_data: Pointer to data buffer
1060  * @size: Amount of data to be sent
1061  * Return 0 on success or a negative value
1062  */
1063 static int i2c_write(struct i2c_handle_s *hi2c, struct i2c_request *request,
1064 		     uint8_t *p_data, uint16_t size)
1065 {
1066 	uint64_t timeout_ref = 0;
1067 	vaddr_t base = get_base(hi2c);
1068 	int rc = -1;
1069 	uint8_t *p_buff = p_data;
1070 	size_t xfer_size = 0;
1071 	size_t xfer_count = size;
1072 
1073 	if (request->mode != I2C_MODE_MASTER && request->mode != I2C_MODE_MEM)
1074 		return -1;
1075 
1076 	if (hi2c->i2c_state != I2C_STATE_READY)
1077 		return -1;
1078 
1079 	if (!p_data || !size)
1080 		return -1;
1081 
1082 	stm32_clock_enable(hi2c->clock);
1083 
1084 	timeout_ref = timeout_init_us(I2C_TIMEOUT_BUSY_MS * 1000);
1085 	if (wait_isr_event(hi2c, I2C_ISR_BUSY, 0, timeout_ref))
1086 		goto bail;
1087 
1088 	hi2c->i2c_state = I2C_STATE_BUSY_TX;
1089 	hi2c->i2c_err = I2C_ERROR_NONE;
1090 	timeout_ref = timeout_init_us(request->timeout_ms * 1000);
1091 
1092 	if (request->mode == I2C_MODE_MEM) {
1093 		/* In memory mode, send slave address and memory address */
1094 		if (i2c_request_mem_write(hi2c, request, timeout_ref))
1095 			goto bail;
1096 
1097 		if (xfer_count > MAX_NBYTE_SIZE) {
1098 			xfer_size = MAX_NBYTE_SIZE;
1099 			i2c_transfer_config(hi2c, request->dev_addr, xfer_size,
1100 					    I2C_RELOAD_MODE, I2C_NO_STARTSTOP);
1101 		} else {
1102 			xfer_size = xfer_count;
1103 			i2c_transfer_config(hi2c, request->dev_addr, xfer_size,
1104 					    I2C_AUTOEND_MODE, I2C_NO_STARTSTOP);
1105 		}
1106 	} else {
1107 		/* In master mode, send slave address */
1108 		if (xfer_count > MAX_NBYTE_SIZE) {
1109 			xfer_size = MAX_NBYTE_SIZE;
1110 			i2c_transfer_config(hi2c, request->dev_addr, xfer_size,
1111 					    I2C_RELOAD_MODE,
1112 					    I2C_GENERATE_START_WRITE);
1113 		} else {
1114 			xfer_size = xfer_count;
1115 			i2c_transfer_config(hi2c, request->dev_addr, xfer_size,
1116 					    I2C_AUTOEND_MODE,
1117 					    I2C_GENERATE_START_WRITE);
1118 		}
1119 	}
1120 
1121 	do {
1122 		if (i2c_wait_txis(hi2c, timeout_ref))
1123 			goto bail;
1124 
1125 		io_write8(base + I2C_TXDR, *p_buff);
1126 		p_buff++;
1127 		xfer_count--;
1128 		xfer_size--;
1129 
1130 		if (xfer_count && !xfer_size) {
1131 			/* Wait until TCR flag is set */
1132 			if (wait_isr_event(hi2c, I2C_ISR_TCR, 1, timeout_ref))
1133 				goto bail;
1134 
1135 			if (xfer_count > MAX_NBYTE_SIZE) {
1136 				xfer_size = MAX_NBYTE_SIZE;
1137 				i2c_transfer_config(hi2c, request->dev_addr,
1138 						    xfer_size,
1139 						    I2C_RELOAD_MODE,
1140 						    I2C_NO_STARTSTOP);
1141 			} else {
1142 				xfer_size = xfer_count;
1143 				i2c_transfer_config(hi2c, request->dev_addr,
1144 						    xfer_size,
1145 						    I2C_AUTOEND_MODE,
1146 						    I2C_NO_STARTSTOP);
1147 			}
1148 		}
1149 
1150 	} while (xfer_count > 0U);
1151 
1152 	/*
1153 	 * No need to Check TC flag, with AUTOEND mode the stop
1154 	 * is automatically generated.
1155 	 * Wait until STOPF flag is reset.
1156 	 */
1157 	if (i2c_wait_stop(hi2c, timeout_ref))
1158 		goto bail;
1159 
1160 	io_write32(base + I2C_ICR, I2C_ISR_STOPF);
1161 
1162 	io_clrbits32(base + I2C_CR2, CR2_RESET_MASK);
1163 
1164 	hi2c->i2c_state = I2C_STATE_READY;
1165 
1166 	rc = 0;
1167 
1168 bail:
1169 	stm32_clock_disable(hi2c->clock);
1170 
1171 	return rc;
1172 }
1173 
1174 int stm32_i2c_mem_write(struct i2c_handle_s *hi2c, uint32_t dev_addr,
1175 			uint32_t mem_addr, uint32_t mem_addr_size,
1176 			uint8_t *p_data, size_t size, unsigned int timeout_ms)
1177 {
1178 	struct i2c_request request = {
1179 		.dev_addr = dev_addr,
1180 		.mode = I2C_MODE_MEM,
1181 		.mem_addr = mem_addr,
1182 		.mem_addr_size = mem_addr_size,
1183 		.timeout_ms = timeout_ms,
1184 	};
1185 
1186 	return i2c_write(hi2c, &request, p_data, size);
1187 }
1188 
1189 int stm32_i2c_master_transmit(struct i2c_handle_s *hi2c, uint32_t dev_addr,
1190 			      uint8_t *p_data, size_t size,
1191 			      unsigned int timeout_ms)
1192 {
1193 	struct i2c_request request = {
1194 		.dev_addr = dev_addr,
1195 		.mode = I2C_MODE_MASTER,
1196 		.timeout_ms = timeout_ms,
1197 	};
1198 
1199 	return i2c_write(hi2c, &request, p_data, size);
1200 }
1201 
1202 int stm32_i2c_read_write_membyte(struct i2c_handle_s *hi2c, uint16_t dev_addr,
1203 				 unsigned int mem_addr, uint8_t *p_data,
1204 				 bool write)
1205 {
1206 	uint64_t timeout_ref = 0;
1207 	uintptr_t base = get_base(hi2c);
1208 	int rc = -1;
1209 	uint8_t *p_buff = p_data;
1210 	uint32_t event_mask = 0;
1211 
1212 	if (hi2c->i2c_state != I2C_STATE_READY || !p_data)
1213 		return -1;
1214 
1215 	stm32_clock_enable(hi2c->clock);
1216 
1217 	timeout_ref = timeout_init_us(I2C_TIMEOUT_BUSY_US);
1218 	if (wait_isr_event(hi2c, I2C_ISR_BUSY, 0, timeout_ref))
1219 		goto bail;
1220 
1221 	hi2c->i2c_state = write ? I2C_STATE_BUSY_TX : I2C_STATE_BUSY_RX;
1222 	hi2c->i2c_err = I2C_ERROR_NONE;
1223 
1224 	i2c_transfer_config(hi2c, dev_addr, I2C_MEMADD_SIZE_8BIT,
1225 			    write ? I2C_RELOAD_MODE : I2C_SOFTEND_MODE,
1226 			    I2C_GENERATE_START_WRITE);
1227 
1228 	timeout_ref = timeout_init_us(I2C_TIMEOUT_BUSY_US);
1229 	if (i2c_wait_txis(hi2c, timeout_ref))
1230 		goto bail;
1231 
1232 	io_write8(base + I2C_TXDR, mem_addr);
1233 
1234 	if (write)
1235 		event_mask = I2C_ISR_TCR;
1236 	else
1237 		event_mask = I2C_ISR_TC;
1238 
1239 	timeout_ref = timeout_init_us(I2C_TIMEOUT_BUSY_US);
1240 	if (wait_isr_event(hi2c, event_mask, 1, timeout_ref))
1241 		goto bail;
1242 
1243 	i2c_transfer_config(hi2c, dev_addr, I2C_MEMADD_SIZE_8BIT,
1244 			    I2C_AUTOEND_MODE,
1245 			    write ? I2C_NO_STARTSTOP : I2C_GENERATE_START_READ);
1246 
1247 	timeout_ref = timeout_init_us(I2C_TIMEOUT_BUSY_US);
1248 	if (write) {
1249 		if (i2c_wait_txis(hi2c, timeout_ref))
1250 			goto bail;
1251 
1252 		io_write8(base + I2C_TXDR, *p_buff);
1253 	} else {
1254 		if (wait_isr_event(hi2c, I2C_ISR_RXNE, 1, timeout_ref))
1255 			goto bail;
1256 
1257 		*p_buff = io_read8(base + I2C_RXDR);
1258 	}
1259 
1260 	timeout_ref = timeout_init_us(I2C_TIMEOUT_BUSY_US);
1261 	if (i2c_wait_stop(hi2c, timeout_ref))
1262 		goto bail;
1263 
1264 	io_write32(base + I2C_ICR, I2C_ISR_STOPF);
1265 	io_clrbits32(base + I2C_CR2, CR2_RESET_MASK);
1266 
1267 	hi2c->i2c_state = I2C_STATE_READY;
1268 
1269 	rc = 0;
1270 
1271 bail:
1272 	stm32_clock_disable(hi2c->clock);
1273 
1274 	return rc;
1275 }
1276 
1277 /*
1278  * Read an amount of data in blocking mode
1279  *
1280  * @hi2c: Reference to struct i2c_handle_s
1281  * @request: I2C request parameters
1282  * @p_data: Pointer to data buffer
1283  * @size: Amount of data to be sent
1284  * Return 0 on success or a negative value
1285  */
1286 static int i2c_read(struct i2c_handle_s *hi2c, struct i2c_request *request,
1287 		    uint8_t *p_data, uint32_t size)
1288 {
1289 	vaddr_t base = get_base(hi2c);
1290 	uint64_t timeout_ref = 0;
1291 	int rc = -1;
1292 	uint8_t *p_buff = p_data;
1293 	size_t xfer_count = size;
1294 	size_t xfer_size = 0;
1295 
1296 	if (request->mode != I2C_MODE_MASTER && request->mode != I2C_MODE_MEM)
1297 		return -1;
1298 
1299 	if (hi2c->i2c_state != I2C_STATE_READY)
1300 		return -1;
1301 
1302 	if (!p_data || !size)
1303 		return -1;
1304 
1305 	stm32_clock_enable(hi2c->clock);
1306 
1307 	timeout_ref = timeout_init_us(I2C_TIMEOUT_BUSY_MS * 1000);
1308 	if (wait_isr_event(hi2c, I2C_ISR_BUSY, 0, timeout_ref))
1309 		goto bail;
1310 
1311 	hi2c->i2c_state = I2C_STATE_BUSY_RX;
1312 	hi2c->i2c_err = I2C_ERROR_NONE;
1313 	timeout_ref = timeout_init_us(request->timeout_ms * 1000);
1314 
1315 	if (request->mode == I2C_MODE_MEM) {
1316 		/* Send memory address */
1317 		if (i2c_request_mem_read(hi2c, request, timeout_ref))
1318 			goto bail;
1319 	}
1320 
1321 	/*
1322 	 * Send slave address.
1323 	 * Set NBYTES to write and reload if xfer_count > MAX_NBYTE_SIZE
1324 	 * and generate RESTART.
1325 	 */
1326 	if (xfer_count > MAX_NBYTE_SIZE) {
1327 		xfer_size = MAX_NBYTE_SIZE;
1328 		i2c_transfer_config(hi2c, request->dev_addr, xfer_size,
1329 				    I2C_RELOAD_MODE, I2C_GENERATE_START_READ);
1330 	} else {
1331 		xfer_size = xfer_count;
1332 		i2c_transfer_config(hi2c, request->dev_addr, xfer_size,
1333 				    I2C_AUTOEND_MODE, I2C_GENERATE_START_READ);
1334 	}
1335 
1336 	do {
1337 		if (wait_isr_event(hi2c, I2C_ISR_RXNE, 1, timeout_ref))
1338 			goto bail;
1339 
1340 		*p_buff = io_read8(base + I2C_RXDR);
1341 		p_buff++;
1342 		xfer_size--;
1343 		xfer_count--;
1344 
1345 		if (xfer_count && !xfer_size) {
1346 			if (wait_isr_event(hi2c, I2C_ISR_TCR, 1, timeout_ref))
1347 				goto bail;
1348 
1349 			if (xfer_count > MAX_NBYTE_SIZE) {
1350 				xfer_size = MAX_NBYTE_SIZE;
1351 				i2c_transfer_config(hi2c, request->dev_addr,
1352 						    xfer_size,
1353 						    I2C_RELOAD_MODE,
1354 						    I2C_NO_STARTSTOP);
1355 			} else {
1356 				xfer_size = xfer_count;
1357 				i2c_transfer_config(hi2c, request->dev_addr,
1358 						    xfer_size,
1359 						    I2C_AUTOEND_MODE,
1360 						    I2C_NO_STARTSTOP);
1361 			}
1362 		}
1363 	} while (xfer_count > 0U);
1364 
1365 	/*
1366 	 * No need to Check TC flag, with AUTOEND mode the stop
1367 	 * is automatically generated.
1368 	 * Wait until STOPF flag is reset.
1369 	 */
1370 	if (i2c_wait_stop(hi2c, timeout_ref))
1371 		goto bail;
1372 
1373 	io_write32(base + I2C_ICR, I2C_ISR_STOPF);
1374 
1375 	io_clrbits32(base + I2C_CR2, CR2_RESET_MASK);
1376 
1377 	hi2c->i2c_state = I2C_STATE_READY;
1378 
1379 	rc = 0;
1380 
1381 bail:
1382 	stm32_clock_disable(hi2c->clock);
1383 
1384 	return rc;
1385 }
1386 
1387 int stm32_i2c_mem_read(struct i2c_handle_s *hi2c, uint32_t dev_addr,
1388 		       uint32_t mem_addr, uint32_t mem_addr_size,
1389 		       uint8_t *p_data, size_t size, unsigned int timeout_ms)
1390 {
1391 	struct i2c_request request = {
1392 		.dev_addr = dev_addr,
1393 		.mode = I2C_MODE_MEM,
1394 		.mem_addr = mem_addr,
1395 		.mem_addr_size = mem_addr_size,
1396 		.timeout_ms = timeout_ms,
1397 	};
1398 
1399 	return i2c_read(hi2c, &request, p_data, size);
1400 }
1401 
1402 int stm32_i2c_master_receive(struct i2c_handle_s *hi2c, uint32_t dev_addr,
1403 			     uint8_t *p_data, size_t size,
1404 			     unsigned int timeout_ms)
1405 {
1406 	struct i2c_request request = {
1407 		.dev_addr = dev_addr,
1408 		.mode = I2C_MODE_MASTER,
1409 		.timeout_ms = timeout_ms,
1410 	};
1411 
1412 	return i2c_read(hi2c, &request, p_data, size);
1413 }
1414 
1415 bool stm32_i2c_is_device_ready(struct i2c_handle_s *hi2c, uint32_t dev_addr,
1416 			       unsigned int trials, unsigned int timeout_ms)
1417 {
1418 	vaddr_t base = get_base(hi2c);
1419 	unsigned int i2c_trials = 0U;
1420 	bool rc = false;
1421 
1422 	if (hi2c->i2c_state != I2C_STATE_READY)
1423 		return rc;
1424 
1425 	stm32_clock_enable(hi2c->clock);
1426 
1427 	if (io_read32(base + I2C_ISR) & I2C_ISR_BUSY)
1428 		goto bail;
1429 
1430 	hi2c->i2c_state = I2C_STATE_BUSY;
1431 	hi2c->i2c_err = I2C_ERROR_NONE;
1432 
1433 	do {
1434 		uint64_t timeout_ref = 0;
1435 		vaddr_t isr = base + I2C_ISR;
1436 
1437 		/* Generate Start */
1438 		if ((io_read32(base + I2C_OAR1) & I2C_OAR1_OA1MODE) == 0)
1439 			io_write32(base + I2C_CR2,
1440 				   ((dev_addr & I2C_CR2_SADD) |
1441 				    I2C_CR2_START | I2C_CR2_AUTOEND) &
1442 				   ~I2C_CR2_RD_WRN);
1443 		else
1444 			io_write32(base + I2C_CR2,
1445 				   ((dev_addr & I2C_CR2_SADD) |
1446 				    I2C_CR2_START | I2C_CR2_ADD10) &
1447 				   ~I2C_CR2_RD_WRN);
1448 
1449 		/*
1450 		 * No need to Check TC flag, with AUTOEND mode the stop
1451 		 * is automatically generated.
1452 		 * Wait until STOPF flag is set or a NACK flag is set.
1453 		 */
1454 		timeout_ref = timeout_init_us(timeout_ms * 1000);
1455 		while (!timeout_elapsed(timeout_ref))
1456 			if (io_read32(isr) & (I2C_ISR_STOPF | I2C_ISR_NACKF))
1457 				break;
1458 
1459 		if ((io_read32(isr) & (I2C_ISR_STOPF | I2C_ISR_NACKF)) == 0) {
1460 			notif_i2c_timeout(hi2c);
1461 			goto bail;
1462 		}
1463 
1464 		if ((io_read32(base + I2C_ISR) & I2C_ISR_NACKF) == 0U) {
1465 			if (wait_isr_event(hi2c, I2C_ISR_STOPF, 1, timeout_ref))
1466 				goto bail;
1467 
1468 			io_write32(base + I2C_ICR, I2C_ISR_STOPF);
1469 
1470 			hi2c->i2c_state = I2C_STATE_READY;
1471 
1472 			rc = true;
1473 			goto bail;
1474 		}
1475 
1476 		if (wait_isr_event(hi2c, I2C_ISR_STOPF, 1, timeout_ref))
1477 			goto bail;
1478 
1479 		io_write32(base + I2C_ICR, I2C_ISR_NACKF);
1480 		io_write32(base + I2C_ICR, I2C_ISR_STOPF);
1481 
1482 		if (i2c_trials == trials) {
1483 			io_setbits32(base + I2C_CR2, I2C_CR2_STOP);
1484 
1485 			if (wait_isr_event(hi2c, I2C_ISR_STOPF, 1, timeout_ref))
1486 				goto bail;
1487 
1488 			io_write32(base + I2C_ICR, I2C_ISR_STOPF);
1489 		}
1490 
1491 		i2c_trials++;
1492 	} while (i2c_trials < trials);
1493 
1494 	notif_i2c_timeout(hi2c);
1495 
1496 bail:
1497 	stm32_clock_disable(hi2c->clock);
1498 
1499 	return rc;
1500 }
1501 
1502 void stm32_i2c_resume(struct i2c_handle_s *hi2c)
1503 {
1504 	if (hi2c->i2c_state == I2C_STATE_READY)
1505 		return;
1506 
1507 	if ((hi2c->i2c_state != I2C_STATE_RESET) &&
1508 	    (hi2c->i2c_state != I2C_STATE_SUSPENDED))
1509 		panic();
1510 
1511 	stm32_pinctrl_load_active_cfg(hi2c->pinctrl, hi2c->pinctrl_count);
1512 
1513 	if (hi2c->i2c_state == I2C_STATE_RESET) {
1514 		/* There is no valid I2C configuration to be loaded yet */
1515 		return;
1516 	}
1517 
1518 	restore_cfg(hi2c, &hi2c->sec_cfg);
1519 
1520 	hi2c->i2c_state = I2C_STATE_READY;
1521 }
1522 
1523 void stm32_i2c_suspend(struct i2c_handle_s *hi2c)
1524 {
1525 	if (hi2c->i2c_state == I2C_STATE_SUSPENDED)
1526 		return;
1527 
1528 	if (hi2c->i2c_state != I2C_STATE_READY)
1529 		panic();
1530 
1531 	save_cfg(hi2c, &hi2c->sec_cfg);
1532 	stm32_pinctrl_load_standby_cfg(hi2c->pinctrl, hi2c->pinctrl_count);
1533 
1534 	hi2c->i2c_state = I2C_STATE_SUSPENDED;
1535 }
1536