xref: /optee_os/core/drivers/stm32_i2c.c (revision 834ce4c65a544eab592f8f339a77d6b7ace4165d)
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/generic_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 
38 /* Bit definition for I2C_CR1 register */
39 #define I2C_CR1_PE			BIT(0)
40 #define I2C_CR1_TXIE			BIT(1)
41 #define I2C_CR1_RXIE			BIT(2)
42 #define I2C_CR1_ADDRIE			BIT(3)
43 #define I2C_CR1_NACKIE			BIT(4)
44 #define I2C_CR1_STOPIE			BIT(5)
45 #define I2C_CR1_TCIE			BIT(6)
46 #define I2C_CR1_ERRIE			BIT(7)
47 #define I2C_CR1_DNF			GENMASK_32(11, 8)
48 #define I2C_CR1_ANFOFF			BIT(12)
49 #define I2C_CR1_SWRST			BIT(13)
50 #define I2C_CR1_TXDMAEN			BIT(14)
51 #define I2C_CR1_RXDMAEN			BIT(15)
52 #define I2C_CR1_SBC			BIT(16)
53 #define I2C_CR1_NOSTRETCH		BIT(17)
54 #define I2C_CR1_WUPEN			BIT(18)
55 #define I2C_CR1_GCEN			BIT(19)
56 #define I2C_CR1_SMBHEN			BIT(22)
57 #define I2C_CR1_SMBDEN			BIT(21)
58 #define I2C_CR1_ALERTEN			BIT(22)
59 #define I2C_CR1_PECEN			BIT(23)
60 
61 /* Bit definition for I2C_CR2 register */
62 #define I2C_CR2_SADD			GENMASK_32(9, 0)
63 #define I2C_CR2_RD_WRN			BIT(10)
64 #define I2C_CR2_RD_WRN_OFFSET		10U
65 #define I2C_CR2_ADD10			BIT(11)
66 #define I2C_CR2_HEAD10R			BIT(12)
67 #define I2C_CR2_START			BIT(13)
68 #define I2C_CR2_STOP			BIT(14)
69 #define I2C_CR2_NACK			BIT(15)
70 #define I2C_CR2_NBYTES			GENMASK_32(23, 16)
71 #define I2C_CR2_NBYTES_OFFSET		16U
72 #define I2C_CR2_RELOAD			BIT(24)
73 #define I2C_CR2_AUTOEND			BIT(25)
74 #define I2C_CR2_PECBYTE			BIT(26)
75 
76 /* Bit definition for I2C_OAR1 register */
77 #define I2C_OAR1_OA1			GENMASK_32(9, 0)
78 #define I2C_OAR1_OA1MODE		BIT(10)
79 #define I2C_OAR1_OA1EN			BIT(15)
80 
81 /* Bit definition for I2C_OAR2 register */
82 #define I2C_OAR2_OA2			GENMASK_32(7, 1)
83 #define I2C_OAR2_OA2MSK			GENMASK_32(10, 8)
84 #define I2C_OAR2_OA2NOMASK		0
85 #define I2C_OAR2_OA2MASK01		BIT(8)
86 #define I2C_OAR2_OA2MASK02		BIT(9)
87 #define I2C_OAR2_OA2MASK03		GENMASK_32(9, 8)
88 #define I2C_OAR2_OA2MASK04		BIT(10)
89 #define I2C_OAR2_OA2MASK05		(BIT(8) | BIT(10))
90 #define I2C_OAR2_OA2MASK06		(BIT(9) | BIT(10))
91 #define I2C_OAR2_OA2MASK07		GENMASK_32(10, 8)
92 #define I2C_OAR2_OA2EN			BIT(15)
93 
94 /* Bit definition for I2C_TIMINGR register */
95 #define I2C_TIMINGR_SCLL		GENMASK_32(7, 0)
96 #define I2C_TIMINGR_SCLH		GENMASK_32(15, 8)
97 #define I2C_TIMINGR_SDADEL		GENMASK_32(19, 16)
98 #define I2C_TIMINGR_SCLDEL		GENMASK_32(23, 20)
99 #define I2C_TIMINGR_PRESC		GENMASK_32(31, 28)
100 #define I2C_TIMINGR_SCLL_MAX		(I2C_TIMINGR_SCLL + 1)
101 #define I2C_TIMINGR_SCLH_MAX		((I2C_TIMINGR_SCLH >> 8) + 1)
102 #define I2C_TIMINGR_SDADEL_MAX		((I2C_TIMINGR_SDADEL >> 16) + 1)
103 #define I2C_TIMINGR_SCLDEL_MAX		((I2C_TIMINGR_SCLDEL >> 20) + 1)
104 #define I2C_TIMINGR_PRESC_MAX		((I2C_TIMINGR_PRESC >> 28) + 1)
105 #define I2C_SET_TIMINGR_SCLL(n)		((n) & \
106 					 (I2C_TIMINGR_SCLL_MAX - 1))
107 #define I2C_SET_TIMINGR_SCLH(n)		(((n) & \
108 					  (I2C_TIMINGR_SCLH_MAX - 1)) << 8)
109 #define I2C_SET_TIMINGR_SDADEL(n)	(((n) & \
110 					  (I2C_TIMINGR_SDADEL_MAX - 1)) << 16)
111 #define I2C_SET_TIMINGR_SCLDEL(n)	(((n) & \
112 					  (I2C_TIMINGR_SCLDEL_MAX - 1)) << 20)
113 #define I2C_SET_TIMINGR_PRESC(n)	(((n) & \
114 					  (I2C_TIMINGR_PRESC_MAX - 1)) << 28)
115 
116 /* Bit definition for I2C_TIMEOUTR register */
117 #define I2C_TIMEOUTR_TIMEOUTA		GENMASK_32(11, 0)
118 #define I2C_TIMEOUTR_TIDLE		BIT(12)
119 #define I2C_TIMEOUTR_TIMOUTEN		BIT(15)
120 #define I2C_TIMEOUTR_TIMEOUTB		GENMASK_32(27, 16)
121 #define I2C_TIMEOUTR_TEXTEN		BIT(31)
122 
123 /* Bit definition for I2C_ISR register */
124 #define I2C_ISR_TXE			BIT(0)
125 #define I2C_ISR_TXIS			BIT(1)
126 #define I2C_ISR_RXNE			BIT(2)
127 #define I2C_ISR_ADDR			BIT(3)
128 #define I2C_ISR_NACKF			BIT(4)
129 #define I2C_ISR_STOPF			BIT(5)
130 #define I2C_ISR_TC			BIT(6)
131 #define I2C_ISR_TCR			BIT(7)
132 #define I2C_ISR_BERR			BIT(8)
133 #define I2C_ISR_ARLO			BIT(9)
134 #define I2C_ISR_OVR			BIT(10)
135 #define I2C_ISR_PECERR			BIT(11)
136 #define I2C_ISR_TIMEOUT			BIT(12)
137 #define I2C_ISR_ALERT			BIT(13)
138 #define I2C_ISR_BUSY			BIT(15)
139 #define I2C_ISR_DIR			BIT(16)
140 #define I2C_ISR_ADDCODE			GENMASK_32(23, 17)
141 
142 /* Bit definition for I2C_ICR register */
143 #define I2C_ICR_ADDRCF			BIT(3)
144 #define I2C_ICR_NACKCF			BIT(4)
145 #define I2C_ICR_STOPCF			BIT(5)
146 #define I2C_ICR_BERRCF			BIT(8)
147 #define I2C_ICR_ARLOCF			BIT(9)
148 #define I2C_ICR_OVRCF			BIT(10)
149 #define I2C_ICR_PECCF			BIT(11)
150 #define I2C_ICR_TIMOUTCF		BIT(12)
151 #define I2C_ICR_ALERTCF			BIT(13)
152 
153 /* Max data size for a single I2C transfer */
154 #define MAX_NBYTE_SIZE			255U
155 
156 #define I2C_NSEC_PER_SEC		1000000000L
157 #define I2C_TIMEOUT_BUSY_MS		25
158 #define I2C_TIMEOUT_BUSY_US		(I2C_TIMEOUT_BUSY_MS * 1000)
159 
160 #define CR2_RESET_MASK			(I2C_CR2_SADD | I2C_CR2_HEAD10R | \
161 					 I2C_CR2_NBYTES | I2C_CR2_RELOAD | \
162 					 I2C_CR2_RD_WRN)
163 
164 #define TIMINGR_CLEAR_MASK		(I2C_TIMINGR_SCLL | I2C_TIMINGR_SCLH | \
165 					 I2C_TIMINGR_SDADEL | \
166 					 I2C_TIMINGR_SCLDEL | I2C_TIMINGR_PRESC)
167 
168 /*
169  * I2C transfer modes
170  * I2C_RELOAD: Enable Reload mode
171  * I2C_AUTOEND_MODE: Enable automatic end mode
172  * I2C_SOFTEND_MODE: Enable software end mode
173  */
174 #define I2C_RELOAD_MODE				I2C_CR2_RELOAD
175 #define I2C_AUTOEND_MODE			I2C_CR2_AUTOEND
176 #define I2C_SOFTEND_MODE			0x0
177 
178 /*
179  * Start/restart/stop I2C transfer requests.
180  *
181  * I2C_NO_STARTSTOP: Don't Generate stop and start condition
182  * I2C_GENERATE_STOP: Generate stop condition (size should be set to 0)
183  * I2C_GENERATE_START_READ: Generate Restart for read request.
184  * I2C_GENERATE_START_WRITE: Generate Restart for write request
185  */
186 #define I2C_NO_STARTSTOP			0x0
187 #define I2C_GENERATE_STOP			(BIT(31) | I2C_CR2_STOP)
188 #define I2C_GENERATE_START_READ			(BIT(31) | I2C_CR2_START | \
189 						 I2C_CR2_RD_WRN)
190 #define I2C_GENERATE_START_WRITE		(BIT(31) | I2C_CR2_START)
191 
192 /* Memory address byte sizes */
193 #define I2C_MEMADD_SIZE_8BIT		1
194 #define I2C_MEMADD_SIZE_16BIT		2
195 
196 /*
197  * struct i2c_spec_s - Private I2C timing specifications.
198  * @rate: I2C bus speed (Hz)
199  * @rate_min: 80% of I2C bus speed (Hz)
200  * @rate_max: 120% of I2C bus speed (Hz)
201  * @fall_max: Max fall time of both SDA and SCL signals (ns)
202  * @rise_max: Max rise time of both SDA and SCL signals (ns)
203  * @hddat_min: Min data hold time (ns)
204  * @vddat_max: Max data valid time (ns)
205  * @sudat_min: Min data setup time (ns)
206  * @l_min: Min low period of the SCL clock (ns)
207  * @h_min: Min high period of the SCL clock (ns)
208  */
209 struct i2c_spec_s {
210 	uint32_t rate;
211 	uint32_t rate_min;
212 	uint32_t rate_max;
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 static const struct i2c_spec_s i2c_specs[] = {
239 	[I2C_SPEED_STANDARD] = {
240 		.rate = I2C_STANDARD_RATE,
241 		.rate_min = (I2C_STANDARD_RATE * 80) / 100,
242 		.rate_max = (I2C_STANDARD_RATE * 120) / 100,
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 	[I2C_SPEED_FAST] = {
252 		.rate = I2C_FAST_RATE,
253 		.rate_min = (I2C_FAST_RATE * 80) / 100,
254 		.rate_max = (I2C_FAST_RATE * 120) / 100,
255 		.fall_max = 300,
256 		.rise_max = 300,
257 		.hddat_min = 0,
258 		.vddat_max = 900,
259 		.sudat_min = 100,
260 		.l_min = 1300,
261 		.h_min = 600,
262 	},
263 	[I2C_SPEED_FAST_PLUS] = {
264 		.rate = I2C_FAST_PLUS_RATE,
265 		.rate_min = (I2C_FAST_PLUS_RATE * 80) / 100,
266 		.rate_max = (I2C_FAST_PLUS_RATE * 120) / 100,
267 		.fall_max = 100,
268 		.rise_max = 120,
269 		.hddat_min = 0,
270 		.vddat_max = 450,
271 		.sudat_min = 50,
272 		.l_min = 500,
273 		.h_min = 260,
274 	},
275 };
276 
277 /*
278  * I2C request parameters
279  * @dev_addr: I2C address of the target device
280  * @mode: Communication mode, one of I2C_MODE_(MASTER|MEM)
281  * @mem_addr: Target memory cell accessed in device (memory mode)
282  * @mem_addr_size: Byte size of the memory cell address (memory mode)
283  * @timeout_ms: Timeout in millisenconds for the request
284  */
285 struct i2c_request {
286 	uint32_t dev_addr;
287 	enum i2c_mode_e mode;
288 	uint32_t mem_addr;
289 	uint32_t mem_addr_size;
290 	unsigned int timeout_ms;
291 };
292 
293 static vaddr_t get_base(struct i2c_handle_s *hi2c)
294 {
295 	return io_pa_or_va_secure(&hi2c->base);
296 }
297 
298 static void notif_i2c_timeout(struct i2c_handle_s *hi2c)
299 {
300 	hi2c->i2c_err |= I2C_ERROR_TIMEOUT;
301 	hi2c->i2c_state = I2C_STATE_READY;
302 }
303 
304 static void save_cfg(struct i2c_handle_s *hi2c, struct i2c_cfg *cfg)
305 {
306 	vaddr_t base = get_base(hi2c);
307 
308 	stm32_clock_enable(hi2c->clock);
309 
310 	cfg->cr1 = io_read32(base + I2C_CR1);
311 	cfg->cr2 = io_read32(base + I2C_CR2);
312 	cfg->oar1 = io_read32(base + I2C_OAR1);
313 	cfg->oar2 = io_read32(base + I2C_OAR2);
314 	cfg->timingr = io_read32(base + I2C_TIMINGR);
315 
316 	stm32_clock_disable(hi2c->clock);
317 }
318 
319 static void restore_cfg(struct i2c_handle_s *hi2c, struct i2c_cfg *cfg)
320 {
321 	vaddr_t base = get_base(hi2c);
322 
323 	stm32_clock_enable(hi2c->clock);
324 
325 	io_clrbits32(base + I2C_CR1, I2C_CR1_PE);
326 	io_write32(base + I2C_TIMINGR, cfg->timingr & TIMINGR_CLEAR_MASK);
327 	io_write32(base + I2C_OAR1, cfg->oar1);
328 	io_write32(base + I2C_CR2, cfg->cr2);
329 	io_write32(base + I2C_OAR2, cfg->oar2);
330 	io_write32(base + I2C_CR1, cfg->cr1 & ~I2C_CR1_PE);
331 	io_setbits32(base + I2C_CR1, cfg->cr1 & I2C_CR1_PE);
332 
333 	stm32_clock_disable(hi2c->clock);
334 }
335 
336 static void __maybe_unused dump_cfg(struct i2c_cfg *cfg __maybe_unused)
337 {
338 	DMSG("CR1:  0x%" PRIx32, cfg->cr1);
339 	DMSG("CR2:  0x%" PRIx32, cfg->cr2);
340 	DMSG("OAR1: 0x%" PRIx32, cfg->oar1);
341 	DMSG("OAR2: 0x%" PRIx32, cfg->oar2);
342 	DMSG("TIM:  0x%" PRIx32, cfg->timingr);
343 }
344 
345 static void __maybe_unused dump_i2c(struct i2c_handle_s *hi2c)
346 {
347 	vaddr_t __maybe_unused base = get_base(hi2c);
348 
349 	stm32_clock_enable(hi2c->clock);
350 
351 	DMSG("CR1:  0x%" PRIx32, io_read32(base + I2C_CR1));
352 	DMSG("CR2:  0x%" PRIx32, io_read32(base + I2C_CR2));
353 	DMSG("OAR1: 0x%" PRIx32, io_read32(base + I2C_OAR1));
354 	DMSG("OAR2: 0x%" PRIx32, io_read32(base + I2C_OAR2));
355 	DMSG("TIM:  0x%" PRIx32, io_read32(base + I2C_TIMINGR));
356 
357 	stm32_clock_disable(hi2c->clock);
358 }
359 
360 /*
361  * Compute the I2C device timings
362  *
363  * @init: Ref to the initialization configuration structure
364  * @clock_src: I2C clock source frequency (Hz)
365  * @timing: Pointer to the final computed timing result
366  * Return 0 on success or a negative value
367  */
368 static int i2c_compute_timing(struct stm32_i2c_init_s *init,
369 			      uint32_t clock_src, uint32_t *timing)
370 {
371 	enum i2c_speed_e mode = init->speed_mode;
372 	uint32_t speed_freq = i2c_specs[mode].rate;
373 	uint32_t i2cbus = UDIV_ROUND_NEAREST(I2C_NSEC_PER_SEC, speed_freq);
374 	uint32_t i2cclk = UDIV_ROUND_NEAREST(I2C_NSEC_PER_SEC, clock_src);
375 	uint32_t p_prev = I2C_TIMINGR_PRESC_MAX;
376 	uint32_t af_delay_min = 0;
377 	uint32_t af_delay_max = 0;
378 	uint32_t dnf_delay = 0;
379 	uint32_t tsync = 0;
380 	uint32_t clk_min = 0;
381 	uint32_t clk_max = 0;
382 	int clk_error_prev = 0;
383 	uint16_t p = 0;
384 	uint16_t l = 0;
385 	uint16_t a = 0;
386 	uint16_t h = 0;
387 	unsigned int sdadel_min = 0;
388 	unsigned int sdadel_max = 0;
389 	unsigned int scldel_min = 0;
390 	unsigned int delay = 0;
391 	int s = -1;
392 	struct i2c_timing_s solutions[I2C_TIMINGR_PRESC_MAX] = { 0 };
393 
394 	switch (mode) {
395 	case I2C_SPEED_STANDARD:
396 	case I2C_SPEED_FAST:
397 	case I2C_SPEED_FAST_PLUS:
398 		break;
399 	default:
400 		EMSG("I2C speed out of bound {%d/%d}",
401 		     mode, I2C_SPEED_FAST_PLUS);
402 		return -1;
403 	}
404 
405 	speed_freq = i2c_specs[mode].rate;
406 	i2cbus = UDIV_ROUND_NEAREST(I2C_NSEC_PER_SEC, speed_freq);
407 	clk_error_prev = INT_MAX;
408 
409 	if ((init->rise_time > i2c_specs[mode].rise_max) ||
410 	    (init->fall_time > i2c_specs[mode].fall_max)) {
411 		EMSG(" I2C timings out of bound: Rise{%d > %d}/Fall{%d > %d}",
412 		     init->rise_time, i2c_specs[mode].rise_max,
413 		     init->fall_time, i2c_specs[mode].fall_max);
414 		return -1;
415 	}
416 
417 	if (init->digital_filter_coef > STM32_I2C_DIGITAL_FILTER_MAX) {
418 		EMSG("DNF out of bound %d/%d",
419 		     init->digital_filter_coef, STM32_I2C_DIGITAL_FILTER_MAX);
420 		return -1;
421 	}
422 
423 	/* Analog and Digital Filters */
424 	if (init->analog_filter) {
425 		af_delay_min = STM32_I2C_ANALOG_FILTER_DELAY_MIN;
426 		af_delay_max = STM32_I2C_ANALOG_FILTER_DELAY_MAX;
427 	}
428 	dnf_delay = init->digital_filter_coef * i2cclk;
429 
430 	sdadel_min = i2c_specs[mode].hddat_min + init->fall_time;
431 	delay = af_delay_min - ((init->digital_filter_coef + 3) * i2cclk);
432 	if (SUB_OVERFLOW(sdadel_min, delay, &sdadel_min))
433 		sdadel_min = 0;
434 
435 	sdadel_max = i2c_specs[mode].vddat_max - init->rise_time;
436 	delay = af_delay_max - ((init->digital_filter_coef + 4) * i2cclk);
437 	if (SUB_OVERFLOW(sdadel_max, delay, &sdadel_max))
438 		sdadel_max = 0;
439 
440 	scldel_min = init->rise_time + i2c_specs[mode].sudat_min;
441 
442 	DMSG("I2C SDADEL(min/max): %u/%u, SCLDEL(Min): %u",
443 	     sdadel_min, sdadel_max, scldel_min);
444 
445 	/* Compute possible values for PRESC, SCLDEL and SDADEL */
446 	for (p = 0; p < I2C_TIMINGR_PRESC_MAX; p++) {
447 		for (l = 0; l < I2C_TIMINGR_SCLDEL_MAX; l++) {
448 			uint32_t scldel = (l + 1) * (p + 1) * i2cclk;
449 
450 			if (scldel < scldel_min)
451 				continue;
452 
453 			for (a = 0; a < I2C_TIMINGR_SDADEL_MAX; a++) {
454 				uint32_t sdadel = (a * (p + 1) + 1) * i2cclk;
455 
456 				if ((sdadel >= sdadel_min) &&
457 				    (sdadel <= sdadel_max) &&
458 				    (p != p_prev)) {
459 					solutions[p].scldel = l;
460 					solutions[p].sdadel = a;
461 					solutions[p].is_saved = true;
462 					p_prev = p;
463 					break;
464 				}
465 			}
466 
467 			if (p_prev == p)
468 				break;
469 		}
470 	}
471 
472 	if (p_prev == I2C_TIMINGR_PRESC_MAX) {
473 		EMSG(" I2C no Prescaler solution");
474 		return -1;
475 	}
476 
477 	tsync = af_delay_min + dnf_delay + (2 * i2cclk);
478 	clk_max = I2C_NSEC_PER_SEC / i2c_specs[mode].rate_min;
479 	clk_min = I2C_NSEC_PER_SEC / i2c_specs[mode].rate_max;
480 
481 	/*
482 	 * Among prescaler possibilities discovered above figures out SCL Low
483 	 * and High Period. Provided:
484 	 * - SCL Low Period has to be higher than Low Period of the SCL Clock
485 	 *   defined by I2C Specification. I2C Clock has to be lower than
486 	 *   (SCL Low Period - Analog/Digital filters) / 4.
487 	 * - SCL High Period has to be lower than High Period of the SCL Clock
488 	 *   defined by I2C Specification.
489 	 * - I2C Clock has to be lower than SCL High Period.
490 	 */
491 	for (p = 0; p < I2C_TIMINGR_PRESC_MAX; p++) {
492 		uint32_t prescaler = (p + 1) * i2cclk;
493 
494 		if (!solutions[p].is_saved)
495 			continue;
496 
497 		for (l = 0; l < I2C_TIMINGR_SCLL_MAX; l++) {
498 			uint32_t tscl_l = ((l + 1) * prescaler) + tsync;
499 
500 			if ((tscl_l < i2c_specs[mode].l_min) ||
501 			    (i2cclk >=
502 			     ((tscl_l - af_delay_min - dnf_delay) / 4)))
503 				continue;
504 
505 			for (h = 0; h < I2C_TIMINGR_SCLH_MAX; h++) {
506 				uint32_t tscl_h = ((h + 1) * prescaler) + tsync;
507 				uint32_t tscl = tscl_l + tscl_h +
508 						init->rise_time +
509 						init->fall_time;
510 
511 				if ((tscl >= clk_min) && (tscl <= clk_max) &&
512 				    (tscl_h >= i2c_specs[mode].h_min) &&
513 				    (i2cclk < tscl_h)) {
514 					int clk_error = tscl - i2cbus;
515 
516 					if (clk_error < 0)
517 						clk_error = -clk_error;
518 
519 					if (clk_error < clk_error_prev) {
520 						clk_error_prev = clk_error;
521 						solutions[p].scll = l;
522 						solutions[p].sclh = h;
523 						s = p;
524 					}
525 				}
526 			}
527 		}
528 	}
529 
530 	if (s < 0) {
531 		EMSG(" I2C no solution at all");
532 		return -1;
533 	}
534 
535 	/* Finalize timing settings */
536 	*timing = I2C_SET_TIMINGR_PRESC(s) |
537 		   I2C_SET_TIMINGR_SCLDEL(solutions[s].scldel) |
538 		   I2C_SET_TIMINGR_SDADEL(solutions[s].sdadel) |
539 		   I2C_SET_TIMINGR_SCLH(solutions[s].sclh) |
540 		   I2C_SET_TIMINGR_SCLL(solutions[s].scll);
541 
542 	DMSG("I2C TIMINGR (PRESC/SCLDEL/SDADEL): %i/%i/%i",
543 		s, solutions[s].scldel, solutions[s].sdadel);
544 	DMSG("I2C TIMINGR (SCLH/SCLL): %i/%i",
545 		solutions[s].sclh, solutions[s].scll);
546 	DMSG("I2C TIMINGR: 0x%x", *timing);
547 
548 	return 0;
549 }
550 
551 /*
552  * Setup the I2C device timings
553  *
554  * @hi2c: I2C handle structure
555  * @init: Ref to the initialization configuration structure
556  * @timing: Output TIMINGR register configuration value
557  * @retval 0 if OK, negative value else
558  */
559 static int i2c_setup_timing(struct i2c_handle_s *hi2c,
560 			    struct stm32_i2c_init_s *init,
561 			    uint32_t *timing)
562 {
563 	int rc = 0;
564 	uint32_t clock_src = stm32_clock_get_rate(hi2c->clock);
565 
566 	if (!clock_src) {
567 		EMSG("Null I2C clock rate");
568 		return -1;
569 	}
570 
571 	do {
572 		rc = i2c_compute_timing(init, clock_src, timing);
573 		if (rc) {
574 			EMSG("Failed to compute I2C timings");
575 			if (init->speed_mode > I2C_SPEED_STANDARD) {
576 				init->speed_mode--;
577 				IMSG("Downgrade I2C speed to %uHz)",
578 				     i2c_specs[init->speed_mode].rate);
579 			} else {
580 				break;
581 			}
582 		}
583 	} while (rc);
584 
585 	if (rc) {
586 		EMSG("Impossible to compute I2C timings");
587 		return rc;
588 	}
589 
590 	DMSG("I2C Speed Mode(%i), Freq(%i), Clk Source(%i)",
591 	     init->speed_mode, i2c_specs[init->speed_mode].rate, clock_src);
592 	DMSG("I2C Rise(%i) and Fall(%i) Time",
593 	     init->rise_time, init->fall_time);
594 	DMSG("I2C Analog Filter(%s), DNF(%i)",
595 	     init->analog_filter ? "On" : "Off", init->digital_filter_coef);
596 
597 	return 0;
598 }
599 
600 /*
601  * Configure I2C Analog noise filter.
602  * @hi2c: I2C handle structure
603  * @analog_filter_on: True if enabling analog filter, false otherwise
604  * Return 0 on success or a negative value
605  */
606 static int i2c_config_analog_filter(struct i2c_handle_s *hi2c,
607 				    bool analog_filter_on)
608 {
609 	vaddr_t base = get_base(hi2c);
610 
611 	if (hi2c->i2c_state != I2C_STATE_READY)
612 		return -1;
613 
614 	hi2c->i2c_state = I2C_STATE_BUSY;
615 
616 	/* Disable the selected I2C peripheral */
617 	io_clrbits32(base + I2C_CR1, I2C_CR1_PE);
618 
619 	/* Reset I2Cx ANOFF bit */
620 	io_clrbits32(base + I2C_CR1, I2C_CR1_ANFOFF);
621 
622 	/* Set analog filter bit if filter is disabled */
623 	if (!analog_filter_on)
624 		io_setbits32(base + I2C_CR1, I2C_CR1_ANFOFF);
625 
626 	/* Enable the selected I2C peripheral */
627 	io_setbits32(base + I2C_CR1, I2C_CR1_PE);
628 
629 	hi2c->i2c_state = I2C_STATE_READY;
630 
631 	return 0;
632 }
633 
634 int stm32_i2c_get_setup_from_fdt(void *fdt, int node,
635 				 struct stm32_i2c_init_s *init,
636 				 struct stm32_pinctrl **pinctrl,
637 				 size_t *pinctrl_count)
638 {
639 	const fdt32_t *cuint = NULL;
640 	struct dt_node_info info = { .status = 0 };
641 	int count = 0;
642 
643 	/* Default STM32 specific configs caller may need to overwrite */
644 	memset(init, 0, sizeof(*init));
645 
646 	_fdt_fill_device_info(fdt, &info, node);
647 	init->pbase = info.reg;
648 	init->clock = info.clock;
649 	assert(info.reg != DT_INFO_INVALID_REG &&
650 	       info.clock != DT_INFO_INVALID_CLOCK);
651 
652 	cuint = fdt_getprop(fdt, node, "i2c-scl-rising-time-ns", NULL);
653 	if (cuint)
654 		init->rise_time = fdt32_to_cpu(*cuint);
655 	else
656 		init->rise_time = STM32_I2C_RISE_TIME_DEFAULT;
657 
658 	cuint = fdt_getprop(fdt, node, "i2c-scl-falling-time-ns", NULL);
659 	if (cuint)
660 		init->fall_time = fdt32_to_cpu(*cuint);
661 	else
662 		init->fall_time = STM32_I2C_FALL_TIME_DEFAULT;
663 
664 	cuint = fdt_getprop(fdt, node, "clock-frequency", NULL);
665 	if (cuint) {
666 		switch (fdt32_to_cpu(*cuint)) {
667 		case I2C_STANDARD_RATE:
668 			init->speed_mode = I2C_SPEED_STANDARD;
669 			break;
670 		case I2C_FAST_RATE:
671 			init->speed_mode = I2C_SPEED_FAST;
672 			break;
673 		case I2C_FAST_PLUS_RATE:
674 			init->speed_mode = I2C_SPEED_FAST_PLUS;
675 			break;
676 		default:
677 			init->speed_mode = STM32_I2C_SPEED_DEFAULT;
678 			break;
679 		}
680 	} else {
681 		init->speed_mode = STM32_I2C_SPEED_DEFAULT;
682 	}
683 
684 	count = stm32_pinctrl_fdt_get_pinctrl(fdt, node, NULL, 0);
685 	if (count <= 0) {
686 		*pinctrl = NULL;
687 		*pinctrl_count = 0;
688 		return count;
689 	}
690 
691 	if (count > 2)
692 		panic("Too many PINCTRLs found");
693 
694 	*pinctrl = calloc(count, sizeof(**pinctrl));
695 	if (!*pinctrl)
696 		panic();
697 
698 	*pinctrl_count = stm32_pinctrl_fdt_get_pinctrl(fdt, node,
699 						       *pinctrl, count);
700 	assert(*pinctrl_count == (unsigned int)count);
701 
702 	return 0;
703 }
704 
705 int stm32_i2c_init(struct i2c_handle_s *hi2c,
706 		   struct stm32_i2c_init_s *init_data)
707 {
708 	int rc = 0;
709 	uint32_t timing = 0;
710 	vaddr_t base = 0;
711 	uint32_t val = 0;
712 
713 	hi2c->base.pa = init_data->pbase;
714 	hi2c->clock = init_data->clock;
715 
716 	rc = i2c_setup_timing(hi2c, init_data, &timing);
717 	if (rc)
718 		return rc;
719 
720 	stm32_clock_enable(hi2c->clock);
721 	base = get_base(hi2c);
722 	hi2c->i2c_state = I2C_STATE_BUSY;
723 
724 	/* Disable the selected I2C peripheral */
725 	io_clrbits32(base + I2C_CR1, I2C_CR1_PE);
726 
727 	/* Configure I2Cx: Frequency range */
728 	io_write32(base + I2C_TIMINGR, timing & TIMINGR_CLEAR_MASK);
729 
730 	/* Disable Own Address1 before set the Own Address1 configuration */
731 	io_write32(base + I2C_OAR1, 0);
732 
733 	/* Configure I2Cx: Own Address1 and ack own address1 mode */
734 	if (init_data->addr_mode_10b_not_7b)
735 		io_write32(base + I2C_OAR1,
736 			   I2C_OAR1_OA1EN | I2C_OAR1_OA1MODE |
737 			   init_data->own_address1);
738 	else
739 		io_write32(base + I2C_OAR1,
740 			   I2C_OAR1_OA1EN | init_data->own_address1);
741 
742 	/* Configure I2Cx: Addressing Master mode */
743 	io_write32(base + I2C_CR2, 0);
744 	if (init_data->addr_mode_10b_not_7b)
745 		io_setbits32(base + I2C_CR2, I2C_CR2_ADD10);
746 
747 	/*
748 	 * Enable the AUTOEND by default, and enable NACK
749 	 * (should be disabled only during Slave process).
750 	 */
751 	io_setbits32(base + I2C_CR2, I2C_CR2_AUTOEND | I2C_CR2_NACK);
752 
753 	/* Disable Own Address2 before set the Own Address2 configuration */
754 	io_write32(base + I2C_OAR2, 0);
755 
756 	/* Configure I2Cx: Dual mode and Own Address2 */
757 	if (init_data->dual_address_mode)
758 		io_write32(base + I2C_OAR2,
759 			   I2C_OAR2_OA2EN | init_data->own_address2 |
760 			   (init_data->own_address2_masks << 8));
761 
762 	/* Configure I2Cx: Generalcall and NoStretch mode */
763 	val = 0;
764 	if (init_data->general_call_mode)
765 		val |= I2C_CR1_GCEN;
766 	if (init_data->no_stretch_mode)
767 		val |= I2C_CR1_NOSTRETCH;
768 	io_write32(base + I2C_CR1, val);
769 
770 	/* Enable the selected I2C peripheral */
771 	io_setbits32(base + I2C_CR1, I2C_CR1_PE);
772 
773 	hi2c->i2c_err = I2C_ERROR_NONE;
774 	hi2c->i2c_state = I2C_STATE_READY;
775 
776 	rc = i2c_config_analog_filter(hi2c, init_data->analog_filter);
777 	if (rc)
778 		EMSG("I2C analog filter error %d", rc);
779 
780 	stm32_clock_disable(hi2c->clock);
781 
782 	return rc;
783 }
784 
785 /* I2C transmit (TX) data register flush sequence */
786 static void i2c_flush_txdr(struct i2c_handle_s *hi2c)
787 {
788 	vaddr_t base = get_base(hi2c);
789 
790 	/*
791 	 * If a pending TXIS flag is set,
792 	 * write a dummy data in TXDR to clear it.
793 	 */
794 	if (io_read32(base + I2C_ISR) & I2C_ISR_TXIS)
795 		io_write32(base + I2C_TXDR, 0);
796 
797 	/* Flush TX register if not empty */
798 	if ((io_read32(base + I2C_ISR) & I2C_ISR_TXE) == 0)
799 		io_setbits32(base + I2C_ISR, I2C_ISR_TXE);
800 }
801 
802 /*
803  * Wait for a single target I2C_ISR bit to reach an awaited value (0 or 1)
804  *
805  * @hi2c: I2C handle structure
806  * @bit_mask: Bit mask for the target single bit position to consider
807  * @awaited_value: Awaited value of the target bit in I2C_ISR, 0 or 1
808  * @timeout_ref: Expriation timeout reference
809  * Return 0 on success and a non-zero value on timeout
810  */
811 static int wait_isr_event(struct i2c_handle_s *hi2c, uint32_t bit_mask,
812 			  unsigned int awaited_value, uint64_t timeout_ref)
813 {
814 	vaddr_t isr = get_base(hi2c) + I2C_ISR;
815 
816 	assert(IS_POWER_OF_TWO(bit_mask) && !(awaited_value & ~1U));
817 
818 	/* May timeout while TEE thread is suspended */
819 	while (!timeout_elapsed(timeout_ref))
820 		if (!!(io_read32(isr) & bit_mask) == awaited_value)
821 			break;
822 
823 	if (!!(io_read32(isr) & bit_mask) == awaited_value)
824 		return 0;
825 
826 	notif_i2c_timeout(hi2c);
827 	return -1;
828 }
829 
830 /* Handle Acknowledge-Failed sequence detection during an I2C Communication */
831 static int i2c_ack_failed(struct i2c_handle_s *hi2c, uint64_t timeout_ref)
832 {
833 	vaddr_t base = get_base(hi2c);
834 
835 	if ((io_read32(base + I2C_ISR) & I2C_ISR_NACKF) == 0U)
836 		return 0;
837 
838 	/*
839 	 * Wait until STOP Flag is reset. Use polling method.
840 	 * AutoEnd should be initiate after AF.
841 	 * Timeout may elpased while TEE thread is suspended.
842 	 */
843 	while (!timeout_elapsed(timeout_ref))
844 		if (io_read32(base + I2C_ISR) & I2C_ISR_STOPF)
845 			break;
846 
847 	if ((io_read32(base + I2C_ISR) & I2C_ISR_STOPF) == 0) {
848 		notif_i2c_timeout(hi2c);
849 		return -1;
850 	}
851 
852 	io_write32(base + I2C_ICR, I2C_ISR_NACKF);
853 
854 	io_write32(base + I2C_ICR, I2C_ISR_STOPF);
855 
856 	i2c_flush_txdr(hi2c);
857 
858 	io_clrbits32(base + I2C_CR2, CR2_RESET_MASK);
859 
860 	hi2c->i2c_err |= I2C_ERROR_ACKF;
861 	hi2c->i2c_state = I2C_STATE_READY;
862 
863 	return -1;
864 }
865 
866 /* Wait TXIS bit is 1 in I2C_ISR register */
867 static int i2c_wait_txis(struct i2c_handle_s *hi2c, uint64_t timeout_ref)
868 {
869 	while (!timeout_elapsed(timeout_ref)) {
870 		if (io_read32(get_base(hi2c) + I2C_ISR) & I2C_ISR_TXIS)
871 			break;
872 		if (i2c_ack_failed(hi2c, timeout_ref))
873 			return -1;
874 	}
875 
876 	if (io_read32(get_base(hi2c) + I2C_ISR) & I2C_ISR_TXIS)
877 		return 0;
878 
879 	if (i2c_ack_failed(hi2c, timeout_ref))
880 		return -1;
881 
882 	notif_i2c_timeout(hi2c);
883 	return -1;
884 }
885 
886 /* Wait STOPF bit is 1 in I2C_ISR register */
887 static int i2c_wait_stop(struct i2c_handle_s *hi2c, uint64_t timeout_ref)
888 {
889 	while (!timeout_elapsed(timeout_ref)) {
890 		if (io_read32(get_base(hi2c) + I2C_ISR) & I2C_ISR_STOPF)
891 			break;
892 
893 		if (i2c_ack_failed(hi2c, timeout_ref))
894 			return -1;
895 	}
896 
897 	if (io_read32(get_base(hi2c) + I2C_ISR) & I2C_ISR_STOPF)
898 		return 0;
899 
900 	if (i2c_ack_failed(hi2c, timeout_ref))
901 		return -1;
902 
903 	notif_i2c_timeout(hi2c);
904 	return -1;
905 }
906 
907 /*
908  * Load I2C_CR2 register for a I2C transfer
909  *
910  * @hi2c: I2C handle structure
911  * @dev_addr: Slave address to be transferred
912  * @size: Number of bytes to be transferred
913  * @i2c_mode: One of I2C_{RELOAD|AUTOEND|SOFTEND}_MODE: Enable Reload mode.
914  * @startstop: One of I2C_NO_STARTSTOP, I2C_GENERATE_STOP,
915  *		I2C_GENERATE_START_{READ|WRITE}
916  */
917 static void i2c_transfer_config(struct i2c_handle_s *hi2c, uint32_t dev_addr,
918 				uint32_t size, uint32_t i2c_mode,
919 				uint32_t startstop)
920 {
921 	uint32_t clr_value = I2C_CR2_SADD | I2C_CR2_NBYTES | I2C_CR2_RELOAD |
922 			     I2C_CR2_AUTOEND | I2C_CR2_START | I2C_CR2_STOP |
923 			     (I2C_CR2_RD_WRN &
924 			      (startstop >> (31U - I2C_CR2_RD_WRN_OFFSET)));
925 	uint32_t set_value = (dev_addr & I2C_CR2_SADD) |
926 			     ((size << I2C_CR2_NBYTES_OFFSET) &
927 			      I2C_CR2_NBYTES) |
928 			     i2c_mode | startstop;
929 
930 	io_clrsetbits32(get_base(hi2c) + I2C_CR2, clr_value, set_value);
931 }
932 
933 /*
934  * Master sends target device address followed by internal memory
935  * address for a memory write request.
936  * Function returns 0 on success or a negative value.
937  */
938 static int i2c_request_mem_write(struct i2c_handle_s *hi2c,
939 				 struct i2c_request *request,
940 				 uint64_t timeout_ref)
941 {
942 	vaddr_t base = get_base(hi2c);
943 
944 	i2c_transfer_config(hi2c, request->dev_addr, request->mem_addr_size,
945 			    I2C_RELOAD_MODE, I2C_GENERATE_START_WRITE);
946 
947 	if (i2c_wait_txis(hi2c, timeout_ref))
948 		return -1;
949 
950 	if (request->mem_addr_size == I2C_MEMADD_SIZE_8BIT) {
951 		/* Send memory address */
952 		io_write8(base + I2C_TXDR, request->mem_addr & 0x00FFU);
953 	} else {
954 		/* Send MSB of memory address */
955 		io_write8(base + I2C_TXDR, (request->mem_addr & 0xFF00U) >> 8);
956 
957 		if (i2c_wait_txis(hi2c, timeout_ref))
958 			return -1;
959 
960 		/* Send LSB of memory address */
961 		io_write8(base + I2C_TXDR, request->mem_addr & 0x00FFU);
962 	}
963 
964 	if (wait_isr_event(hi2c, I2C_ISR_TCR, 1, timeout_ref))
965 		return -1;
966 
967 	return 0;
968 }
969 
970 /*
971  * Master sends target device address followed by internal memory
972  * address to prepare a memory read request.
973  * Function returns 0 on success or a negative value.
974  */
975 static int i2c_request_mem_read(struct i2c_handle_s *hi2c,
976 				struct i2c_request *request,
977 				uint64_t timeout_ref)
978 {
979 	vaddr_t base = get_base(hi2c);
980 
981 	i2c_transfer_config(hi2c, request->dev_addr, request->mem_addr_size,
982 			    I2C_SOFTEND_MODE, I2C_GENERATE_START_WRITE);
983 
984 	if (i2c_wait_txis(hi2c, timeout_ref))
985 		return -1;
986 
987 	if (request->mem_addr_size == I2C_MEMADD_SIZE_8BIT) {
988 		/* Send memory address */
989 		io_write8(base + I2C_TXDR, request->mem_addr & 0x00FFU);
990 	} else {
991 		/* Send MSB of memory address */
992 		io_write8(base + I2C_TXDR, (request->mem_addr & 0xFF00U) >> 8);
993 
994 		if (i2c_wait_txis(hi2c, timeout_ref))
995 			return -1;
996 
997 		/* Send LSB of memory address */
998 		io_write8(base + I2C_TXDR, request->mem_addr & 0x00FFU);
999 	}
1000 
1001 	if (wait_isr_event(hi2c, I2C_ISR_TC, 1, timeout_ref))
1002 		return -1;
1003 
1004 	return 0;
1005 }
1006 
1007 /*
1008  * Write an amount of data in blocking mode
1009  *
1010  * @hi2c: Reference to struct i2c_handle_s
1011  * @request: I2C request parameters
1012  * @p_data: Pointer to data buffer
1013  * @size: Amount of data to be sent
1014  * Return 0 on success or a negative value
1015  */
1016 static int i2c_write(struct i2c_handle_s *hi2c, struct i2c_request *request,
1017 		     uint8_t *p_data, uint16_t size)
1018 {
1019 	uint64_t timeout_ref = 0;
1020 	vaddr_t base = get_base(hi2c);
1021 	int rc = -1;
1022 	uint8_t *p_buff = p_data;
1023 	size_t xfer_size = 0;
1024 	size_t xfer_count = size;
1025 
1026 	if (request->mode != I2C_MODE_MASTER && request->mode != I2C_MODE_MEM)
1027 		return -1;
1028 
1029 	if (hi2c->i2c_state != I2C_STATE_READY)
1030 		return -1;
1031 
1032 	if (!p_data || !size)
1033 		return -1;
1034 
1035 	stm32_clock_enable(hi2c->clock);
1036 
1037 	timeout_ref = timeout_init_us(I2C_TIMEOUT_BUSY_MS * 1000);
1038 	if (wait_isr_event(hi2c, I2C_ISR_BUSY, 0, timeout_ref))
1039 		goto bail;
1040 
1041 	hi2c->i2c_state = I2C_STATE_BUSY_TX;
1042 	hi2c->i2c_err = I2C_ERROR_NONE;
1043 	timeout_ref = timeout_init_us(request->timeout_ms * 1000);
1044 
1045 	if (request->mode == I2C_MODE_MEM) {
1046 		/* In memory mode, send slave address and memory address */
1047 		if (i2c_request_mem_write(hi2c, request, timeout_ref))
1048 			goto bail;
1049 
1050 		if (xfer_count > MAX_NBYTE_SIZE) {
1051 			xfer_size = MAX_NBYTE_SIZE;
1052 			i2c_transfer_config(hi2c, request->dev_addr, xfer_size,
1053 					    I2C_RELOAD_MODE, I2C_NO_STARTSTOP);
1054 		} else {
1055 			xfer_size = xfer_count;
1056 			i2c_transfer_config(hi2c, request->dev_addr, xfer_size,
1057 					    I2C_AUTOEND_MODE, I2C_NO_STARTSTOP);
1058 		}
1059 	} else {
1060 		/* In master mode, send slave address */
1061 		if (xfer_count > MAX_NBYTE_SIZE) {
1062 			xfer_size = MAX_NBYTE_SIZE;
1063 			i2c_transfer_config(hi2c, request->dev_addr, xfer_size,
1064 					    I2C_RELOAD_MODE,
1065 					    I2C_GENERATE_START_WRITE);
1066 		} else {
1067 			xfer_size = xfer_count;
1068 			i2c_transfer_config(hi2c, request->dev_addr, xfer_size,
1069 					    I2C_AUTOEND_MODE,
1070 					    I2C_GENERATE_START_WRITE);
1071 		}
1072 	}
1073 
1074 	do {
1075 		if (i2c_wait_txis(hi2c, timeout_ref))
1076 			goto bail;
1077 
1078 		io_write8(base + I2C_TXDR, *p_buff);
1079 		p_buff++;
1080 		xfer_count--;
1081 		xfer_size--;
1082 
1083 		if (xfer_count && !xfer_size) {
1084 			/* Wait until TCR flag is set */
1085 			if (wait_isr_event(hi2c, I2C_ISR_TCR, 1, timeout_ref))
1086 				goto bail;
1087 
1088 			if (xfer_count > MAX_NBYTE_SIZE) {
1089 				xfer_size = MAX_NBYTE_SIZE;
1090 				i2c_transfer_config(hi2c, request->dev_addr,
1091 						    xfer_size,
1092 						    I2C_RELOAD_MODE,
1093 						    I2C_NO_STARTSTOP);
1094 			} else {
1095 				xfer_size = xfer_count;
1096 				i2c_transfer_config(hi2c, request->dev_addr,
1097 						    xfer_size,
1098 						    I2C_AUTOEND_MODE,
1099 						    I2C_NO_STARTSTOP);
1100 			}
1101 		}
1102 
1103 	} while (xfer_count > 0U);
1104 
1105 	/*
1106 	 * No need to Check TC flag, with AUTOEND mode the stop
1107 	 * is automatically generated.
1108 	 * Wait until STOPF flag is reset.
1109 	 */
1110 	if (i2c_wait_stop(hi2c, timeout_ref))
1111 		goto bail;
1112 
1113 	io_write32(base + I2C_ICR, I2C_ISR_STOPF);
1114 
1115 	io_clrbits32(base + I2C_CR2, CR2_RESET_MASK);
1116 
1117 	hi2c->i2c_state = I2C_STATE_READY;
1118 
1119 	rc = 0;
1120 
1121 bail:
1122 	stm32_clock_disable(hi2c->clock);
1123 
1124 	return rc;
1125 }
1126 
1127 int stm32_i2c_mem_write(struct i2c_handle_s *hi2c, uint32_t dev_addr,
1128 			uint32_t mem_addr, uint32_t mem_addr_size,
1129 			uint8_t *p_data, size_t size, unsigned int timeout_ms)
1130 {
1131 	struct i2c_request request = {
1132 		.dev_addr = dev_addr,
1133 		.mode = I2C_MODE_MEM,
1134 		.mem_addr = mem_addr,
1135 		.mem_addr_size = mem_addr_size,
1136 		.timeout_ms = timeout_ms,
1137 	};
1138 
1139 	return i2c_write(hi2c, &request, p_data, size);
1140 }
1141 
1142 int stm32_i2c_master_transmit(struct i2c_handle_s *hi2c, uint32_t dev_addr,
1143 			      uint8_t *p_data, size_t size,
1144 			      unsigned int timeout_ms)
1145 {
1146 	struct i2c_request request = {
1147 		.dev_addr = dev_addr,
1148 		.mode = I2C_MODE_MASTER,
1149 		.timeout_ms = timeout_ms,
1150 	};
1151 
1152 	return i2c_write(hi2c, &request, p_data, size);
1153 }
1154 
1155 int stm32_i2c_read_write_membyte(struct i2c_handle_s *hi2c, uint16_t dev_addr,
1156 				 unsigned int mem_addr, uint8_t *p_data,
1157 				 bool write)
1158 {
1159 	uint64_t timeout_ref = 0;
1160 	uintptr_t base = get_base(hi2c);
1161 	int rc = -1;
1162 	uint8_t *p_buff = p_data;
1163 	uint32_t event_mask = 0;
1164 
1165 	if (hi2c->i2c_state != I2C_STATE_READY || !p_data)
1166 		return -1;
1167 
1168 	stm32_clock_enable(hi2c->clock);
1169 
1170 	timeout_ref = timeout_init_us(I2C_TIMEOUT_BUSY_US);
1171 	if (wait_isr_event(hi2c, I2C_ISR_BUSY, 0, timeout_ref))
1172 		goto bail;
1173 
1174 	hi2c->i2c_state = write ? I2C_STATE_BUSY_TX : I2C_STATE_BUSY_RX;
1175 	hi2c->i2c_err = I2C_ERROR_NONE;
1176 
1177 	i2c_transfer_config(hi2c, dev_addr, I2C_MEMADD_SIZE_8BIT,
1178 			    write ? I2C_RELOAD_MODE : I2C_SOFTEND_MODE,
1179 			    I2C_GENERATE_START_WRITE);
1180 
1181 	timeout_ref = timeout_init_us(I2C_TIMEOUT_BUSY_US);
1182 	if (i2c_wait_txis(hi2c, timeout_ref))
1183 		goto bail;
1184 
1185 	io_write8(base + I2C_TXDR, mem_addr);
1186 
1187 	if (write)
1188 		event_mask = I2C_ISR_TCR;
1189 	else
1190 		event_mask = I2C_ISR_TC;
1191 
1192 	timeout_ref = timeout_init_us(I2C_TIMEOUT_BUSY_US);
1193 	if (wait_isr_event(hi2c, event_mask, 1, timeout_ref))
1194 		goto bail;
1195 
1196 	i2c_transfer_config(hi2c, dev_addr, I2C_MEMADD_SIZE_8BIT,
1197 			    I2C_AUTOEND_MODE,
1198 			    write ? I2C_NO_STARTSTOP : I2C_GENERATE_START_READ);
1199 
1200 	timeout_ref = timeout_init_us(I2C_TIMEOUT_BUSY_US);
1201 	if (write) {
1202 		if (i2c_wait_txis(hi2c, timeout_ref))
1203 			goto bail;
1204 
1205 		io_write8(base + I2C_TXDR, *p_buff);
1206 	} else {
1207 		if (wait_isr_event(hi2c, I2C_ISR_RXNE, 1, timeout_ref))
1208 			goto bail;
1209 
1210 		*p_buff = io_read8(base + I2C_RXDR);
1211 	}
1212 
1213 	timeout_ref = timeout_init_us(I2C_TIMEOUT_BUSY_US);
1214 	if (i2c_wait_stop(hi2c, timeout_ref))
1215 		goto bail;
1216 
1217 	io_write32(base + I2C_ICR, I2C_ISR_STOPF);
1218 	io_clrbits32(base + I2C_CR2, CR2_RESET_MASK);
1219 
1220 	hi2c->i2c_state = I2C_STATE_READY;
1221 
1222 	rc = 0;
1223 
1224 bail:
1225 	stm32_clock_disable(hi2c->clock);
1226 
1227 	return rc;
1228 }
1229 
1230 /*
1231  * Read an amount of data in blocking mode
1232  *
1233  * @hi2c: Reference to struct i2c_handle_s
1234  * @request: I2C request parameters
1235  * @p_data: Pointer to data buffer
1236  * @size: Amount of data to be sent
1237  * Return 0 on success or a negative value
1238  */
1239 static int i2c_read(struct i2c_handle_s *hi2c, struct i2c_request *request,
1240 		    uint8_t *p_data, uint32_t size)
1241 {
1242 	vaddr_t base = get_base(hi2c);
1243 	uint64_t timeout_ref = 0;
1244 	int rc = -1;
1245 	uint8_t *p_buff = p_data;
1246 	size_t xfer_count = size;
1247 	size_t xfer_size = 0;
1248 
1249 	if (request->mode != I2C_MODE_MASTER && request->mode != I2C_MODE_MEM)
1250 		return -1;
1251 
1252 	if (hi2c->i2c_state != I2C_STATE_READY)
1253 		return -1;
1254 
1255 	if (!p_data || !size)
1256 		return -1;
1257 
1258 	stm32_clock_enable(hi2c->clock);
1259 
1260 	timeout_ref = timeout_init_us(I2C_TIMEOUT_BUSY_MS * 1000);
1261 	if (wait_isr_event(hi2c, I2C_ISR_BUSY, 0, timeout_ref))
1262 		goto bail;
1263 
1264 	hi2c->i2c_state = I2C_STATE_BUSY_RX;
1265 	hi2c->i2c_err = I2C_ERROR_NONE;
1266 	timeout_ref = timeout_init_us(request->timeout_ms * 1000);
1267 
1268 	if (request->mode == I2C_MODE_MEM) {
1269 		/* Send memory address */
1270 		if (i2c_request_mem_read(hi2c, request, timeout_ref))
1271 			goto bail;
1272 	}
1273 
1274 	/*
1275 	 * Send slave address.
1276 	 * Set NBYTES to write and reload if xfer_count > MAX_NBYTE_SIZE
1277 	 * and generate RESTART.
1278 	 */
1279 	if (xfer_count > MAX_NBYTE_SIZE) {
1280 		xfer_size = MAX_NBYTE_SIZE;
1281 		i2c_transfer_config(hi2c, request->dev_addr, xfer_size,
1282 				    I2C_RELOAD_MODE, I2C_GENERATE_START_READ);
1283 	} else {
1284 		xfer_size = xfer_count;
1285 		i2c_transfer_config(hi2c, request->dev_addr, xfer_size,
1286 				    I2C_AUTOEND_MODE, I2C_GENERATE_START_READ);
1287 	}
1288 
1289 	do {
1290 		if (wait_isr_event(hi2c, I2C_ISR_RXNE, 1, timeout_ref))
1291 			goto bail;
1292 
1293 		*p_buff = io_read8(base + I2C_RXDR);
1294 		p_buff++;
1295 		xfer_size--;
1296 		xfer_count--;
1297 
1298 		if (xfer_count && !xfer_size) {
1299 			if (wait_isr_event(hi2c, I2C_ISR_TCR, 1, timeout_ref))
1300 				goto bail;
1301 
1302 			if (xfer_count > MAX_NBYTE_SIZE) {
1303 				xfer_size = MAX_NBYTE_SIZE;
1304 				i2c_transfer_config(hi2c, request->dev_addr,
1305 						    xfer_size,
1306 						    I2C_RELOAD_MODE,
1307 						    I2C_NO_STARTSTOP);
1308 			} else {
1309 				xfer_size = xfer_count;
1310 				i2c_transfer_config(hi2c, request->dev_addr,
1311 						    xfer_size,
1312 						    I2C_AUTOEND_MODE,
1313 						    I2C_NO_STARTSTOP);
1314 			}
1315 		}
1316 	} while (xfer_count > 0U);
1317 
1318 	/*
1319 	 * No need to Check TC flag, with AUTOEND mode the stop
1320 	 * is automatically generated.
1321 	 * Wait until STOPF flag is reset.
1322 	 */
1323 	if (i2c_wait_stop(hi2c, timeout_ref))
1324 		goto bail;
1325 
1326 	io_write32(base + I2C_ICR, I2C_ISR_STOPF);
1327 
1328 	io_clrbits32(base + I2C_CR2, CR2_RESET_MASK);
1329 
1330 	hi2c->i2c_state = I2C_STATE_READY;
1331 
1332 	rc = 0;
1333 
1334 bail:
1335 	stm32_clock_disable(hi2c->clock);
1336 
1337 	return rc;
1338 }
1339 
1340 int stm32_i2c_mem_read(struct i2c_handle_s *hi2c, uint32_t dev_addr,
1341 		       uint32_t mem_addr, uint32_t mem_addr_size,
1342 		       uint8_t *p_data, size_t size, unsigned int timeout_ms)
1343 {
1344 	struct i2c_request request = {
1345 		.dev_addr = dev_addr,
1346 		.mode = I2C_MODE_MEM,
1347 		.mem_addr = mem_addr,
1348 		.mem_addr_size = mem_addr_size,
1349 		.timeout_ms = timeout_ms,
1350 	};
1351 
1352 	return i2c_read(hi2c, &request, p_data, size);
1353 }
1354 
1355 int stm32_i2c_master_receive(struct i2c_handle_s *hi2c, uint32_t dev_addr,
1356 			     uint8_t *p_data, size_t size,
1357 			     unsigned int timeout_ms)
1358 {
1359 	struct i2c_request request = {
1360 		.dev_addr = dev_addr,
1361 		.mode = I2C_MODE_MASTER,
1362 		.timeout_ms = timeout_ms,
1363 	};
1364 
1365 	return i2c_read(hi2c, &request, p_data, size);
1366 }
1367 
1368 bool stm32_i2c_is_device_ready(struct i2c_handle_s *hi2c, uint32_t dev_addr,
1369 			       unsigned int trials, unsigned int timeout_ms)
1370 {
1371 	vaddr_t base = get_base(hi2c);
1372 	unsigned int i2c_trials = 0U;
1373 	bool rc = false;
1374 
1375 	if (hi2c->i2c_state != I2C_STATE_READY)
1376 		return rc;
1377 
1378 	stm32_clock_enable(hi2c->clock);
1379 
1380 	if (io_read32(base + I2C_ISR) & I2C_ISR_BUSY)
1381 		goto bail;
1382 
1383 	hi2c->i2c_state = I2C_STATE_BUSY;
1384 	hi2c->i2c_err = I2C_ERROR_NONE;
1385 
1386 	do {
1387 		uint64_t timeout_ref = 0;
1388 		vaddr_t isr = base + I2C_ISR;
1389 
1390 		/* Generate Start */
1391 		if ((io_read32(base + I2C_OAR1) & I2C_OAR1_OA1MODE) == 0)
1392 			io_write32(base + I2C_CR2,
1393 				   ((dev_addr & I2C_CR2_SADD) |
1394 				    I2C_CR2_START | I2C_CR2_AUTOEND) &
1395 				   ~I2C_CR2_RD_WRN);
1396 		else
1397 			io_write32(base + I2C_CR2,
1398 				   ((dev_addr & I2C_CR2_SADD) |
1399 				    I2C_CR2_START | I2C_CR2_ADD10) &
1400 				   ~I2C_CR2_RD_WRN);
1401 
1402 		/*
1403 		 * No need to Check TC flag, with AUTOEND mode the stop
1404 		 * is automatically generated.
1405 		 * Wait until STOPF flag is set or a NACK flag is set.
1406 		 */
1407 		timeout_ref = timeout_init_us(timeout_ms * 1000);
1408 		while (!timeout_elapsed(timeout_ref))
1409 			if (io_read32(isr) & (I2C_ISR_STOPF | I2C_ISR_NACKF))
1410 				break;
1411 
1412 		if ((io_read32(isr) & (I2C_ISR_STOPF | I2C_ISR_NACKF)) == 0) {
1413 			notif_i2c_timeout(hi2c);
1414 			goto bail;
1415 		}
1416 
1417 		if ((io_read32(base + I2C_ISR) & I2C_ISR_NACKF) == 0U) {
1418 			if (wait_isr_event(hi2c, I2C_ISR_STOPF, 1, timeout_ref))
1419 				goto bail;
1420 
1421 			io_write32(base + I2C_ICR, I2C_ISR_STOPF);
1422 
1423 			hi2c->i2c_state = I2C_STATE_READY;
1424 
1425 			rc = true;
1426 			goto bail;
1427 		}
1428 
1429 		if (wait_isr_event(hi2c, I2C_ISR_STOPF, 1, timeout_ref))
1430 			goto bail;
1431 
1432 		io_write32(base + I2C_ICR, I2C_ISR_NACKF);
1433 		io_write32(base + I2C_ICR, I2C_ISR_STOPF);
1434 
1435 		if (i2c_trials == trials) {
1436 			io_setbits32(base + I2C_CR2, I2C_CR2_STOP);
1437 
1438 			if (wait_isr_event(hi2c, I2C_ISR_STOPF, 1, timeout_ref))
1439 				goto bail;
1440 
1441 			io_write32(base + I2C_ICR, I2C_ISR_STOPF);
1442 		}
1443 
1444 		i2c_trials++;
1445 	} while (i2c_trials < trials);
1446 
1447 	notif_i2c_timeout(hi2c);
1448 
1449 bail:
1450 	stm32_clock_disable(hi2c->clock);
1451 
1452 	return rc;
1453 }
1454 
1455 void stm32_i2c_resume(struct i2c_handle_s *hi2c)
1456 {
1457 	if (hi2c->i2c_state == I2C_STATE_READY)
1458 		return;
1459 
1460 	if ((hi2c->i2c_state != I2C_STATE_RESET) &&
1461 	    (hi2c->i2c_state != I2C_STATE_SUSPENDED))
1462 		panic();
1463 
1464 	stm32_pinctrl_load_active_cfg(hi2c->pinctrl, hi2c->pinctrl_count);
1465 
1466 	if (hi2c->i2c_state == I2C_STATE_RESET) {
1467 		/* There is no valid I2C configuration to be loaded yet */
1468 		return;
1469 	}
1470 
1471 	restore_cfg(hi2c, &hi2c->sec_cfg);
1472 
1473 	hi2c->i2c_state = I2C_STATE_READY;
1474 }
1475 
1476 void stm32_i2c_suspend(struct i2c_handle_s *hi2c)
1477 {
1478 	if (hi2c->i2c_state == I2C_STATE_SUSPENDED)
1479 		return;
1480 
1481 	if (hi2c->i2c_state != I2C_STATE_READY)
1482 		panic();
1483 
1484 	save_cfg(hi2c, &hi2c->sec_cfg);
1485 	stm32_pinctrl_load_standby_cfg(hi2c->pinctrl, hi2c->pinctrl_count);
1486 
1487 	hi2c->i2c_state = I2C_STATE_SUSPENDED;
1488 }
1489