xref: /optee_os/core/drivers/stm32_i2c.c (revision 31c3d89f9f9dae01de5a6d9b56c3b50e50d03985)
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 	/*
572 	 * If the timing has already been computed, and the frequency is the
573 	 * same as when it was computed, then use the saved timing.
574 	 */
575 	if (clock_src == hi2c->saved_frequency) {
576 		*timing = hi2c->saved_timing;
577 		return 0;
578 	}
579 
580 	do {
581 		rc = i2c_compute_timing(init, clock_src, timing);
582 		if (rc) {
583 			EMSG("Failed to compute I2C timings");
584 			if (init->speed_mode > I2C_SPEED_STANDARD) {
585 				init->speed_mode--;
586 				IMSG("Downgrade I2C speed to %uHz)",
587 				     i2c_specs[init->speed_mode].rate);
588 			} else {
589 				break;
590 			}
591 		}
592 	} while (rc);
593 
594 	if (rc) {
595 		EMSG("Impossible to compute I2C timings");
596 		return rc;
597 	}
598 
599 	DMSG("I2C Speed Mode(%i), Freq(%i), Clk Source(%i)",
600 	     init->speed_mode, i2c_specs[init->speed_mode].rate, clock_src);
601 	DMSG("I2C Rise(%i) and Fall(%i) Time",
602 	     init->rise_time, init->fall_time);
603 	DMSG("I2C Analog Filter(%s), DNF(%i)",
604 	     init->analog_filter ? "On" : "Off", init->digital_filter_coef);
605 
606 	hi2c->saved_timing = *timing;
607 	hi2c->saved_frequency = clock_src;
608 
609 	return 0;
610 }
611 
612 /*
613  * Configure I2C Analog noise filter.
614  * @hi2c: I2C handle structure
615  * @analog_filter_on: True if enabling analog filter, false otherwise
616  * Return 0 on success or a negative value
617  */
618 static int i2c_config_analog_filter(struct i2c_handle_s *hi2c,
619 				    bool analog_filter_on)
620 {
621 	vaddr_t base = get_base(hi2c);
622 
623 	if (hi2c->i2c_state != I2C_STATE_READY)
624 		return -1;
625 
626 	hi2c->i2c_state = I2C_STATE_BUSY;
627 
628 	/* Disable the selected I2C peripheral */
629 	io_clrbits32(base + I2C_CR1, I2C_CR1_PE);
630 
631 	/* Reset I2Cx ANOFF bit */
632 	io_clrbits32(base + I2C_CR1, I2C_CR1_ANFOFF);
633 
634 	/* Set analog filter bit if filter is disabled */
635 	if (!analog_filter_on)
636 		io_setbits32(base + I2C_CR1, I2C_CR1_ANFOFF);
637 
638 	/* Enable the selected I2C peripheral */
639 	io_setbits32(base + I2C_CR1, I2C_CR1_PE);
640 
641 	hi2c->i2c_state = I2C_STATE_READY;
642 
643 	return 0;
644 }
645 
646 int stm32_i2c_get_setup_from_fdt(void *fdt, int node,
647 				 struct stm32_i2c_init_s *init,
648 				 struct stm32_pinctrl **pinctrl,
649 				 size_t *pinctrl_count)
650 {
651 	const fdt32_t *cuint = NULL;
652 	struct dt_node_info info = { .status = 0 };
653 	int count = 0;
654 
655 	/* Default STM32 specific configs caller may need to overwrite */
656 	memset(init, 0, sizeof(*init));
657 
658 	_fdt_fill_device_info(fdt, &info, node);
659 	init->dt_status = info.status;
660 	init->pbase = info.reg;
661 	init->clock = info.clock;
662 	assert(info.reg != DT_INFO_INVALID_REG &&
663 	       info.clock != DT_INFO_INVALID_CLOCK);
664 
665 	cuint = fdt_getprop(fdt, node, "i2c-scl-rising-time-ns", NULL);
666 	if (cuint)
667 		init->rise_time = fdt32_to_cpu(*cuint);
668 	else
669 		init->rise_time = STM32_I2C_RISE_TIME_DEFAULT;
670 
671 	cuint = fdt_getprop(fdt, node, "i2c-scl-falling-time-ns", NULL);
672 	if (cuint)
673 		init->fall_time = fdt32_to_cpu(*cuint);
674 	else
675 		init->fall_time = STM32_I2C_FALL_TIME_DEFAULT;
676 
677 	cuint = fdt_getprop(fdt, node, "clock-frequency", NULL);
678 	if (cuint) {
679 		switch (fdt32_to_cpu(*cuint)) {
680 		case I2C_STANDARD_RATE:
681 			init->speed_mode = I2C_SPEED_STANDARD;
682 			break;
683 		case I2C_FAST_RATE:
684 			init->speed_mode = I2C_SPEED_FAST;
685 			break;
686 		case I2C_FAST_PLUS_RATE:
687 			init->speed_mode = I2C_SPEED_FAST_PLUS;
688 			break;
689 		default:
690 			init->speed_mode = STM32_I2C_SPEED_DEFAULT;
691 			break;
692 		}
693 	} else {
694 		init->speed_mode = STM32_I2C_SPEED_DEFAULT;
695 	}
696 
697 	count = stm32_pinctrl_fdt_get_pinctrl(fdt, node, NULL, 0);
698 	if (count <= 0) {
699 		*pinctrl = NULL;
700 		*pinctrl_count = 0;
701 		return count;
702 	}
703 
704 	if (count > 2)
705 		panic("Too many PINCTRLs found");
706 
707 	*pinctrl = calloc(count, sizeof(**pinctrl));
708 	if (!*pinctrl)
709 		panic();
710 
711 	*pinctrl_count = stm32_pinctrl_fdt_get_pinctrl(fdt, node,
712 						       *pinctrl, count);
713 	assert(*pinctrl_count == (unsigned int)count);
714 
715 	return 0;
716 }
717 
718 int stm32_i2c_init(struct i2c_handle_s *hi2c,
719 		   struct stm32_i2c_init_s *init_data)
720 {
721 	int rc = 0;
722 	uint32_t timing = 0;
723 	vaddr_t base = 0;
724 	uint32_t val = 0;
725 
726 	hi2c->dt_status = init_data->dt_status;
727 	hi2c->base.pa = init_data->pbase;
728 	hi2c->clock = init_data->clock;
729 
730 	rc = i2c_setup_timing(hi2c, init_data, &timing);
731 	if (rc)
732 		return rc;
733 
734 	stm32_clock_enable(hi2c->clock);
735 	base = get_base(hi2c);
736 	hi2c->i2c_state = I2C_STATE_BUSY;
737 
738 	/* Disable the selected I2C peripheral */
739 	io_clrbits32(base + I2C_CR1, I2C_CR1_PE);
740 
741 	/* Configure I2Cx: Frequency range */
742 	io_write32(base + I2C_TIMINGR, timing & TIMINGR_CLEAR_MASK);
743 
744 	/* Disable Own Address1 before set the Own Address1 configuration */
745 	io_write32(base + I2C_OAR1, 0);
746 
747 	/* Configure I2Cx: Own Address1 and ack own address1 mode */
748 	if (init_data->addr_mode_10b_not_7b)
749 		io_write32(base + I2C_OAR1,
750 			   I2C_OAR1_OA1EN | I2C_OAR1_OA1MODE |
751 			   init_data->own_address1);
752 	else
753 		io_write32(base + I2C_OAR1,
754 			   I2C_OAR1_OA1EN | init_data->own_address1);
755 
756 	/* Configure I2Cx: Addressing Master mode */
757 	io_write32(base + I2C_CR2, 0);
758 	if (init_data->addr_mode_10b_not_7b)
759 		io_setbits32(base + I2C_CR2, I2C_CR2_ADD10);
760 
761 	/*
762 	 * Enable the AUTOEND by default, and enable NACK
763 	 * (should be disabled only during Slave process).
764 	 */
765 	io_setbits32(base + I2C_CR2, I2C_CR2_AUTOEND | I2C_CR2_NACK);
766 
767 	/* Disable Own Address2 before set the Own Address2 configuration */
768 	io_write32(base + I2C_OAR2, 0);
769 
770 	/* Configure I2Cx: Dual mode and Own Address2 */
771 	if (init_data->dual_address_mode)
772 		io_write32(base + I2C_OAR2,
773 			   I2C_OAR2_OA2EN | init_data->own_address2 |
774 			   (init_data->own_address2_masks << 8));
775 
776 	/* Configure I2Cx: Generalcall and NoStretch mode */
777 	val = 0;
778 	if (init_data->general_call_mode)
779 		val |= I2C_CR1_GCEN;
780 	if (init_data->no_stretch_mode)
781 		val |= I2C_CR1_NOSTRETCH;
782 	io_write32(base + I2C_CR1, val);
783 
784 	/* Enable the selected I2C peripheral */
785 	io_setbits32(base + I2C_CR1, I2C_CR1_PE);
786 
787 	hi2c->i2c_err = I2C_ERROR_NONE;
788 	hi2c->i2c_state = I2C_STATE_READY;
789 
790 	rc = i2c_config_analog_filter(hi2c, init_data->analog_filter);
791 	if (rc)
792 		EMSG("I2C analog filter error %d", rc);
793 
794 	stm32_clock_disable(hi2c->clock);
795 
796 	return rc;
797 }
798 
799 /* I2C transmit (TX) data register flush sequence */
800 static void i2c_flush_txdr(struct i2c_handle_s *hi2c)
801 {
802 	vaddr_t base = get_base(hi2c);
803 
804 	/*
805 	 * If a pending TXIS flag is set,
806 	 * write a dummy data in TXDR to clear it.
807 	 */
808 	if (io_read32(base + I2C_ISR) & I2C_ISR_TXIS)
809 		io_write32(base + I2C_TXDR, 0);
810 
811 	/* Flush TX register if not empty */
812 	if ((io_read32(base + I2C_ISR) & I2C_ISR_TXE) == 0)
813 		io_setbits32(base + I2C_ISR, I2C_ISR_TXE);
814 }
815 
816 /*
817  * Wait for a single target I2C_ISR bit to reach an awaited value (0 or 1)
818  *
819  * @hi2c: I2C handle structure
820  * @bit_mask: Bit mask for the target single bit position to consider
821  * @awaited_value: Awaited value of the target bit in I2C_ISR, 0 or 1
822  * @timeout_ref: Expriation timeout reference
823  * Return 0 on success and a non-zero value on timeout
824  */
825 static int wait_isr_event(struct i2c_handle_s *hi2c, uint32_t bit_mask,
826 			  unsigned int awaited_value, uint64_t timeout_ref)
827 {
828 	vaddr_t isr = get_base(hi2c) + I2C_ISR;
829 
830 	assert(IS_POWER_OF_TWO(bit_mask) && !(awaited_value & ~1U));
831 
832 	/* May timeout while TEE thread is suspended */
833 	while (!timeout_elapsed(timeout_ref))
834 		if (!!(io_read32(isr) & bit_mask) == awaited_value)
835 			break;
836 
837 	if (!!(io_read32(isr) & bit_mask) == awaited_value)
838 		return 0;
839 
840 	notif_i2c_timeout(hi2c);
841 	return -1;
842 }
843 
844 /* Handle Acknowledge-Failed sequence detection during an I2C Communication */
845 static int i2c_ack_failed(struct i2c_handle_s *hi2c, uint64_t timeout_ref)
846 {
847 	vaddr_t base = get_base(hi2c);
848 
849 	if ((io_read32(base + I2C_ISR) & I2C_ISR_NACKF) == 0U)
850 		return 0;
851 
852 	/*
853 	 * Wait until STOP Flag is reset. Use polling method.
854 	 * AutoEnd should be initiate after AF.
855 	 * Timeout may elpased while TEE thread is suspended.
856 	 */
857 	while (!timeout_elapsed(timeout_ref))
858 		if (io_read32(base + I2C_ISR) & I2C_ISR_STOPF)
859 			break;
860 
861 	if ((io_read32(base + I2C_ISR) & I2C_ISR_STOPF) == 0) {
862 		notif_i2c_timeout(hi2c);
863 		return -1;
864 	}
865 
866 	io_write32(base + I2C_ICR, I2C_ISR_NACKF);
867 
868 	io_write32(base + I2C_ICR, I2C_ISR_STOPF);
869 
870 	i2c_flush_txdr(hi2c);
871 
872 	io_clrbits32(base + I2C_CR2, CR2_RESET_MASK);
873 
874 	hi2c->i2c_err |= I2C_ERROR_ACKF;
875 	hi2c->i2c_state = I2C_STATE_READY;
876 
877 	return -1;
878 }
879 
880 /* Wait TXIS bit is 1 in I2C_ISR register */
881 static int i2c_wait_txis(struct i2c_handle_s *hi2c, uint64_t timeout_ref)
882 {
883 	while (!timeout_elapsed(timeout_ref)) {
884 		if (io_read32(get_base(hi2c) + I2C_ISR) & I2C_ISR_TXIS)
885 			break;
886 		if (i2c_ack_failed(hi2c, timeout_ref))
887 			return -1;
888 	}
889 
890 	if (io_read32(get_base(hi2c) + I2C_ISR) & I2C_ISR_TXIS)
891 		return 0;
892 
893 	if (i2c_ack_failed(hi2c, timeout_ref))
894 		return -1;
895 
896 	notif_i2c_timeout(hi2c);
897 	return -1;
898 }
899 
900 /* Wait STOPF bit is 1 in I2C_ISR register */
901 static int i2c_wait_stop(struct i2c_handle_s *hi2c, uint64_t timeout_ref)
902 {
903 	while (!timeout_elapsed(timeout_ref)) {
904 		if (io_read32(get_base(hi2c) + I2C_ISR) & I2C_ISR_STOPF)
905 			break;
906 
907 		if (i2c_ack_failed(hi2c, timeout_ref))
908 			return -1;
909 	}
910 
911 	if (io_read32(get_base(hi2c) + I2C_ISR) & I2C_ISR_STOPF)
912 		return 0;
913 
914 	if (i2c_ack_failed(hi2c, timeout_ref))
915 		return -1;
916 
917 	notif_i2c_timeout(hi2c);
918 	return -1;
919 }
920 
921 /*
922  * Load I2C_CR2 register for a I2C transfer
923  *
924  * @hi2c: I2C handle structure
925  * @dev_addr: Slave address to be transferred
926  * @size: Number of bytes to be transferred
927  * @i2c_mode: One of I2C_{RELOAD|AUTOEND|SOFTEND}_MODE: Enable Reload mode.
928  * @startstop: One of I2C_NO_STARTSTOP, I2C_GENERATE_STOP,
929  *		I2C_GENERATE_START_{READ|WRITE}
930  */
931 static void i2c_transfer_config(struct i2c_handle_s *hi2c, uint32_t dev_addr,
932 				uint32_t size, uint32_t i2c_mode,
933 				uint32_t startstop)
934 {
935 	uint32_t clr_value = I2C_CR2_SADD | I2C_CR2_NBYTES | I2C_CR2_RELOAD |
936 			     I2C_CR2_AUTOEND | I2C_CR2_START | I2C_CR2_STOP |
937 			     (I2C_CR2_RD_WRN &
938 			      (startstop >> (31U - I2C_CR2_RD_WRN_OFFSET)));
939 	uint32_t set_value = (dev_addr & I2C_CR2_SADD) |
940 			     ((size << I2C_CR2_NBYTES_OFFSET) &
941 			      I2C_CR2_NBYTES) |
942 			     i2c_mode | startstop;
943 
944 	io_clrsetbits32(get_base(hi2c) + I2C_CR2, clr_value, set_value);
945 }
946 
947 /*
948  * Master sends target device address followed by internal memory
949  * address for a memory write request.
950  * Function returns 0 on success or a negative value.
951  */
952 static int i2c_request_mem_write(struct i2c_handle_s *hi2c,
953 				 struct i2c_request *request,
954 				 uint64_t timeout_ref)
955 {
956 	vaddr_t base = get_base(hi2c);
957 
958 	i2c_transfer_config(hi2c, request->dev_addr, request->mem_addr_size,
959 			    I2C_RELOAD_MODE, I2C_GENERATE_START_WRITE);
960 
961 	if (i2c_wait_txis(hi2c, timeout_ref))
962 		return -1;
963 
964 	if (request->mem_addr_size == I2C_MEMADD_SIZE_8BIT) {
965 		/* Send memory address */
966 		io_write8(base + I2C_TXDR, request->mem_addr & 0x00FFU);
967 	} else {
968 		/* Send MSB of memory address */
969 		io_write8(base + I2C_TXDR, (request->mem_addr & 0xFF00U) >> 8);
970 
971 		if (i2c_wait_txis(hi2c, timeout_ref))
972 			return -1;
973 
974 		/* Send LSB of memory address */
975 		io_write8(base + I2C_TXDR, request->mem_addr & 0x00FFU);
976 	}
977 
978 	if (wait_isr_event(hi2c, I2C_ISR_TCR, 1, timeout_ref))
979 		return -1;
980 
981 	return 0;
982 }
983 
984 /*
985  * Master sends target device address followed by internal memory
986  * address to prepare a memory read request.
987  * Function returns 0 on success or a negative value.
988  */
989 static int i2c_request_mem_read(struct i2c_handle_s *hi2c,
990 				struct i2c_request *request,
991 				uint64_t timeout_ref)
992 {
993 	vaddr_t base = get_base(hi2c);
994 
995 	i2c_transfer_config(hi2c, request->dev_addr, request->mem_addr_size,
996 			    I2C_SOFTEND_MODE, I2C_GENERATE_START_WRITE);
997 
998 	if (i2c_wait_txis(hi2c, timeout_ref))
999 		return -1;
1000 
1001 	if (request->mem_addr_size == I2C_MEMADD_SIZE_8BIT) {
1002 		/* Send memory address */
1003 		io_write8(base + I2C_TXDR, request->mem_addr & 0x00FFU);
1004 	} else {
1005 		/* Send MSB of memory address */
1006 		io_write8(base + I2C_TXDR, (request->mem_addr & 0xFF00U) >> 8);
1007 
1008 		if (i2c_wait_txis(hi2c, timeout_ref))
1009 			return -1;
1010 
1011 		/* Send LSB of memory address */
1012 		io_write8(base + I2C_TXDR, request->mem_addr & 0x00FFU);
1013 	}
1014 
1015 	if (wait_isr_event(hi2c, I2C_ISR_TC, 1, timeout_ref))
1016 		return -1;
1017 
1018 	return 0;
1019 }
1020 
1021 /*
1022  * Write an amount of data in blocking mode
1023  *
1024  * @hi2c: Reference to struct i2c_handle_s
1025  * @request: I2C request parameters
1026  * @p_data: Pointer to data buffer
1027  * @size: Amount of data to be sent
1028  * Return 0 on success or a negative value
1029  */
1030 static int i2c_write(struct i2c_handle_s *hi2c, struct i2c_request *request,
1031 		     uint8_t *p_data, uint16_t size)
1032 {
1033 	uint64_t timeout_ref = 0;
1034 	vaddr_t base = get_base(hi2c);
1035 	int rc = -1;
1036 	uint8_t *p_buff = p_data;
1037 	size_t xfer_size = 0;
1038 	size_t xfer_count = size;
1039 
1040 	if (request->mode != I2C_MODE_MASTER && request->mode != I2C_MODE_MEM)
1041 		return -1;
1042 
1043 	if (hi2c->i2c_state != I2C_STATE_READY)
1044 		return -1;
1045 
1046 	if (!p_data || !size)
1047 		return -1;
1048 
1049 	stm32_clock_enable(hi2c->clock);
1050 
1051 	timeout_ref = timeout_init_us(I2C_TIMEOUT_BUSY_MS * 1000);
1052 	if (wait_isr_event(hi2c, I2C_ISR_BUSY, 0, timeout_ref))
1053 		goto bail;
1054 
1055 	hi2c->i2c_state = I2C_STATE_BUSY_TX;
1056 	hi2c->i2c_err = I2C_ERROR_NONE;
1057 	timeout_ref = timeout_init_us(request->timeout_ms * 1000);
1058 
1059 	if (request->mode == I2C_MODE_MEM) {
1060 		/* In memory mode, send slave address and memory address */
1061 		if (i2c_request_mem_write(hi2c, request, timeout_ref))
1062 			goto bail;
1063 
1064 		if (xfer_count > MAX_NBYTE_SIZE) {
1065 			xfer_size = MAX_NBYTE_SIZE;
1066 			i2c_transfer_config(hi2c, request->dev_addr, xfer_size,
1067 					    I2C_RELOAD_MODE, I2C_NO_STARTSTOP);
1068 		} else {
1069 			xfer_size = xfer_count;
1070 			i2c_transfer_config(hi2c, request->dev_addr, xfer_size,
1071 					    I2C_AUTOEND_MODE, I2C_NO_STARTSTOP);
1072 		}
1073 	} else {
1074 		/* In master mode, send slave address */
1075 		if (xfer_count > MAX_NBYTE_SIZE) {
1076 			xfer_size = MAX_NBYTE_SIZE;
1077 			i2c_transfer_config(hi2c, request->dev_addr, xfer_size,
1078 					    I2C_RELOAD_MODE,
1079 					    I2C_GENERATE_START_WRITE);
1080 		} else {
1081 			xfer_size = xfer_count;
1082 			i2c_transfer_config(hi2c, request->dev_addr, xfer_size,
1083 					    I2C_AUTOEND_MODE,
1084 					    I2C_GENERATE_START_WRITE);
1085 		}
1086 	}
1087 
1088 	do {
1089 		if (i2c_wait_txis(hi2c, timeout_ref))
1090 			goto bail;
1091 
1092 		io_write8(base + I2C_TXDR, *p_buff);
1093 		p_buff++;
1094 		xfer_count--;
1095 		xfer_size--;
1096 
1097 		if (xfer_count && !xfer_size) {
1098 			/* Wait until TCR flag is set */
1099 			if (wait_isr_event(hi2c, I2C_ISR_TCR, 1, timeout_ref))
1100 				goto bail;
1101 
1102 			if (xfer_count > MAX_NBYTE_SIZE) {
1103 				xfer_size = MAX_NBYTE_SIZE;
1104 				i2c_transfer_config(hi2c, request->dev_addr,
1105 						    xfer_size,
1106 						    I2C_RELOAD_MODE,
1107 						    I2C_NO_STARTSTOP);
1108 			} else {
1109 				xfer_size = xfer_count;
1110 				i2c_transfer_config(hi2c, request->dev_addr,
1111 						    xfer_size,
1112 						    I2C_AUTOEND_MODE,
1113 						    I2C_NO_STARTSTOP);
1114 			}
1115 		}
1116 
1117 	} while (xfer_count > 0U);
1118 
1119 	/*
1120 	 * No need to Check TC flag, with AUTOEND mode the stop
1121 	 * is automatically generated.
1122 	 * Wait until STOPF flag is reset.
1123 	 */
1124 	if (i2c_wait_stop(hi2c, timeout_ref))
1125 		goto bail;
1126 
1127 	io_write32(base + I2C_ICR, I2C_ISR_STOPF);
1128 
1129 	io_clrbits32(base + I2C_CR2, CR2_RESET_MASK);
1130 
1131 	hi2c->i2c_state = I2C_STATE_READY;
1132 
1133 	rc = 0;
1134 
1135 bail:
1136 	stm32_clock_disable(hi2c->clock);
1137 
1138 	return rc;
1139 }
1140 
1141 int stm32_i2c_mem_write(struct i2c_handle_s *hi2c, uint32_t dev_addr,
1142 			uint32_t mem_addr, uint32_t mem_addr_size,
1143 			uint8_t *p_data, size_t size, unsigned int timeout_ms)
1144 {
1145 	struct i2c_request request = {
1146 		.dev_addr = dev_addr,
1147 		.mode = I2C_MODE_MEM,
1148 		.mem_addr = mem_addr,
1149 		.mem_addr_size = mem_addr_size,
1150 		.timeout_ms = timeout_ms,
1151 	};
1152 
1153 	return i2c_write(hi2c, &request, p_data, size);
1154 }
1155 
1156 int stm32_i2c_master_transmit(struct i2c_handle_s *hi2c, uint32_t dev_addr,
1157 			      uint8_t *p_data, size_t size,
1158 			      unsigned int timeout_ms)
1159 {
1160 	struct i2c_request request = {
1161 		.dev_addr = dev_addr,
1162 		.mode = I2C_MODE_MASTER,
1163 		.timeout_ms = timeout_ms,
1164 	};
1165 
1166 	return i2c_write(hi2c, &request, p_data, size);
1167 }
1168 
1169 int stm32_i2c_read_write_membyte(struct i2c_handle_s *hi2c, uint16_t dev_addr,
1170 				 unsigned int mem_addr, uint8_t *p_data,
1171 				 bool write)
1172 {
1173 	uint64_t timeout_ref = 0;
1174 	uintptr_t base = get_base(hi2c);
1175 	int rc = -1;
1176 	uint8_t *p_buff = p_data;
1177 	uint32_t event_mask = 0;
1178 
1179 	if (hi2c->i2c_state != I2C_STATE_READY || !p_data)
1180 		return -1;
1181 
1182 	stm32_clock_enable(hi2c->clock);
1183 
1184 	timeout_ref = timeout_init_us(I2C_TIMEOUT_BUSY_US);
1185 	if (wait_isr_event(hi2c, I2C_ISR_BUSY, 0, timeout_ref))
1186 		goto bail;
1187 
1188 	hi2c->i2c_state = write ? I2C_STATE_BUSY_TX : I2C_STATE_BUSY_RX;
1189 	hi2c->i2c_err = I2C_ERROR_NONE;
1190 
1191 	i2c_transfer_config(hi2c, dev_addr, I2C_MEMADD_SIZE_8BIT,
1192 			    write ? I2C_RELOAD_MODE : I2C_SOFTEND_MODE,
1193 			    I2C_GENERATE_START_WRITE);
1194 
1195 	timeout_ref = timeout_init_us(I2C_TIMEOUT_BUSY_US);
1196 	if (i2c_wait_txis(hi2c, timeout_ref))
1197 		goto bail;
1198 
1199 	io_write8(base + I2C_TXDR, mem_addr);
1200 
1201 	if (write)
1202 		event_mask = I2C_ISR_TCR;
1203 	else
1204 		event_mask = I2C_ISR_TC;
1205 
1206 	timeout_ref = timeout_init_us(I2C_TIMEOUT_BUSY_US);
1207 	if (wait_isr_event(hi2c, event_mask, 1, timeout_ref))
1208 		goto bail;
1209 
1210 	i2c_transfer_config(hi2c, dev_addr, I2C_MEMADD_SIZE_8BIT,
1211 			    I2C_AUTOEND_MODE,
1212 			    write ? I2C_NO_STARTSTOP : I2C_GENERATE_START_READ);
1213 
1214 	timeout_ref = timeout_init_us(I2C_TIMEOUT_BUSY_US);
1215 	if (write) {
1216 		if (i2c_wait_txis(hi2c, timeout_ref))
1217 			goto bail;
1218 
1219 		io_write8(base + I2C_TXDR, *p_buff);
1220 	} else {
1221 		if (wait_isr_event(hi2c, I2C_ISR_RXNE, 1, timeout_ref))
1222 			goto bail;
1223 
1224 		*p_buff = io_read8(base + I2C_RXDR);
1225 	}
1226 
1227 	timeout_ref = timeout_init_us(I2C_TIMEOUT_BUSY_US);
1228 	if (i2c_wait_stop(hi2c, timeout_ref))
1229 		goto bail;
1230 
1231 	io_write32(base + I2C_ICR, I2C_ISR_STOPF);
1232 	io_clrbits32(base + I2C_CR2, CR2_RESET_MASK);
1233 
1234 	hi2c->i2c_state = I2C_STATE_READY;
1235 
1236 	rc = 0;
1237 
1238 bail:
1239 	stm32_clock_disable(hi2c->clock);
1240 
1241 	return rc;
1242 }
1243 
1244 /*
1245  * Read an amount of data in blocking mode
1246  *
1247  * @hi2c: Reference to struct i2c_handle_s
1248  * @request: I2C request parameters
1249  * @p_data: Pointer to data buffer
1250  * @size: Amount of data to be sent
1251  * Return 0 on success or a negative value
1252  */
1253 static int i2c_read(struct i2c_handle_s *hi2c, struct i2c_request *request,
1254 		    uint8_t *p_data, uint32_t size)
1255 {
1256 	vaddr_t base = get_base(hi2c);
1257 	uint64_t timeout_ref = 0;
1258 	int rc = -1;
1259 	uint8_t *p_buff = p_data;
1260 	size_t xfer_count = size;
1261 	size_t xfer_size = 0;
1262 
1263 	if (request->mode != I2C_MODE_MASTER && request->mode != I2C_MODE_MEM)
1264 		return -1;
1265 
1266 	if (hi2c->i2c_state != I2C_STATE_READY)
1267 		return -1;
1268 
1269 	if (!p_data || !size)
1270 		return -1;
1271 
1272 	stm32_clock_enable(hi2c->clock);
1273 
1274 	timeout_ref = timeout_init_us(I2C_TIMEOUT_BUSY_MS * 1000);
1275 	if (wait_isr_event(hi2c, I2C_ISR_BUSY, 0, timeout_ref))
1276 		goto bail;
1277 
1278 	hi2c->i2c_state = I2C_STATE_BUSY_RX;
1279 	hi2c->i2c_err = I2C_ERROR_NONE;
1280 	timeout_ref = timeout_init_us(request->timeout_ms * 1000);
1281 
1282 	if (request->mode == I2C_MODE_MEM) {
1283 		/* Send memory address */
1284 		if (i2c_request_mem_read(hi2c, request, timeout_ref))
1285 			goto bail;
1286 	}
1287 
1288 	/*
1289 	 * Send slave address.
1290 	 * Set NBYTES to write and reload if xfer_count > MAX_NBYTE_SIZE
1291 	 * and generate RESTART.
1292 	 */
1293 	if (xfer_count > MAX_NBYTE_SIZE) {
1294 		xfer_size = MAX_NBYTE_SIZE;
1295 		i2c_transfer_config(hi2c, request->dev_addr, xfer_size,
1296 				    I2C_RELOAD_MODE, I2C_GENERATE_START_READ);
1297 	} else {
1298 		xfer_size = xfer_count;
1299 		i2c_transfer_config(hi2c, request->dev_addr, xfer_size,
1300 				    I2C_AUTOEND_MODE, I2C_GENERATE_START_READ);
1301 	}
1302 
1303 	do {
1304 		if (wait_isr_event(hi2c, I2C_ISR_RXNE, 1, timeout_ref))
1305 			goto bail;
1306 
1307 		*p_buff = io_read8(base + I2C_RXDR);
1308 		p_buff++;
1309 		xfer_size--;
1310 		xfer_count--;
1311 
1312 		if (xfer_count && !xfer_size) {
1313 			if (wait_isr_event(hi2c, I2C_ISR_TCR, 1, timeout_ref))
1314 				goto bail;
1315 
1316 			if (xfer_count > MAX_NBYTE_SIZE) {
1317 				xfer_size = MAX_NBYTE_SIZE;
1318 				i2c_transfer_config(hi2c, request->dev_addr,
1319 						    xfer_size,
1320 						    I2C_RELOAD_MODE,
1321 						    I2C_NO_STARTSTOP);
1322 			} else {
1323 				xfer_size = xfer_count;
1324 				i2c_transfer_config(hi2c, request->dev_addr,
1325 						    xfer_size,
1326 						    I2C_AUTOEND_MODE,
1327 						    I2C_NO_STARTSTOP);
1328 			}
1329 		}
1330 	} while (xfer_count > 0U);
1331 
1332 	/*
1333 	 * No need to Check TC flag, with AUTOEND mode the stop
1334 	 * is automatically generated.
1335 	 * Wait until STOPF flag is reset.
1336 	 */
1337 	if (i2c_wait_stop(hi2c, timeout_ref))
1338 		goto bail;
1339 
1340 	io_write32(base + I2C_ICR, I2C_ISR_STOPF);
1341 
1342 	io_clrbits32(base + I2C_CR2, CR2_RESET_MASK);
1343 
1344 	hi2c->i2c_state = I2C_STATE_READY;
1345 
1346 	rc = 0;
1347 
1348 bail:
1349 	stm32_clock_disable(hi2c->clock);
1350 
1351 	return rc;
1352 }
1353 
1354 int stm32_i2c_mem_read(struct i2c_handle_s *hi2c, uint32_t dev_addr,
1355 		       uint32_t mem_addr, uint32_t mem_addr_size,
1356 		       uint8_t *p_data, size_t size, unsigned int timeout_ms)
1357 {
1358 	struct i2c_request request = {
1359 		.dev_addr = dev_addr,
1360 		.mode = I2C_MODE_MEM,
1361 		.mem_addr = mem_addr,
1362 		.mem_addr_size = mem_addr_size,
1363 		.timeout_ms = timeout_ms,
1364 	};
1365 
1366 	return i2c_read(hi2c, &request, p_data, size);
1367 }
1368 
1369 int stm32_i2c_master_receive(struct i2c_handle_s *hi2c, uint32_t dev_addr,
1370 			     uint8_t *p_data, size_t size,
1371 			     unsigned int timeout_ms)
1372 {
1373 	struct i2c_request request = {
1374 		.dev_addr = dev_addr,
1375 		.mode = I2C_MODE_MASTER,
1376 		.timeout_ms = timeout_ms,
1377 	};
1378 
1379 	return i2c_read(hi2c, &request, p_data, size);
1380 }
1381 
1382 bool stm32_i2c_is_device_ready(struct i2c_handle_s *hi2c, uint32_t dev_addr,
1383 			       unsigned int trials, unsigned int timeout_ms)
1384 {
1385 	vaddr_t base = get_base(hi2c);
1386 	unsigned int i2c_trials = 0U;
1387 	bool rc = false;
1388 
1389 	if (hi2c->i2c_state != I2C_STATE_READY)
1390 		return rc;
1391 
1392 	stm32_clock_enable(hi2c->clock);
1393 
1394 	if (io_read32(base + I2C_ISR) & I2C_ISR_BUSY)
1395 		goto bail;
1396 
1397 	hi2c->i2c_state = I2C_STATE_BUSY;
1398 	hi2c->i2c_err = I2C_ERROR_NONE;
1399 
1400 	do {
1401 		uint64_t timeout_ref = 0;
1402 		vaddr_t isr = base + I2C_ISR;
1403 
1404 		/* Generate Start */
1405 		if ((io_read32(base + I2C_OAR1) & I2C_OAR1_OA1MODE) == 0)
1406 			io_write32(base + I2C_CR2,
1407 				   ((dev_addr & I2C_CR2_SADD) |
1408 				    I2C_CR2_START | I2C_CR2_AUTOEND) &
1409 				   ~I2C_CR2_RD_WRN);
1410 		else
1411 			io_write32(base + I2C_CR2,
1412 				   ((dev_addr & I2C_CR2_SADD) |
1413 				    I2C_CR2_START | I2C_CR2_ADD10) &
1414 				   ~I2C_CR2_RD_WRN);
1415 
1416 		/*
1417 		 * No need to Check TC flag, with AUTOEND mode the stop
1418 		 * is automatically generated.
1419 		 * Wait until STOPF flag is set or a NACK flag is set.
1420 		 */
1421 		timeout_ref = timeout_init_us(timeout_ms * 1000);
1422 		while (!timeout_elapsed(timeout_ref))
1423 			if (io_read32(isr) & (I2C_ISR_STOPF | I2C_ISR_NACKF))
1424 				break;
1425 
1426 		if ((io_read32(isr) & (I2C_ISR_STOPF | I2C_ISR_NACKF)) == 0) {
1427 			notif_i2c_timeout(hi2c);
1428 			goto bail;
1429 		}
1430 
1431 		if ((io_read32(base + I2C_ISR) & I2C_ISR_NACKF) == 0U) {
1432 			if (wait_isr_event(hi2c, I2C_ISR_STOPF, 1, timeout_ref))
1433 				goto bail;
1434 
1435 			io_write32(base + I2C_ICR, I2C_ISR_STOPF);
1436 
1437 			hi2c->i2c_state = I2C_STATE_READY;
1438 
1439 			rc = true;
1440 			goto bail;
1441 		}
1442 
1443 		if (wait_isr_event(hi2c, I2C_ISR_STOPF, 1, timeout_ref))
1444 			goto bail;
1445 
1446 		io_write32(base + I2C_ICR, I2C_ISR_NACKF);
1447 		io_write32(base + I2C_ICR, I2C_ISR_STOPF);
1448 
1449 		if (i2c_trials == trials) {
1450 			io_setbits32(base + I2C_CR2, I2C_CR2_STOP);
1451 
1452 			if (wait_isr_event(hi2c, I2C_ISR_STOPF, 1, timeout_ref))
1453 				goto bail;
1454 
1455 			io_write32(base + I2C_ICR, I2C_ISR_STOPF);
1456 		}
1457 
1458 		i2c_trials++;
1459 	} while (i2c_trials < trials);
1460 
1461 	notif_i2c_timeout(hi2c);
1462 
1463 bail:
1464 	stm32_clock_disable(hi2c->clock);
1465 
1466 	return rc;
1467 }
1468 
1469 void stm32_i2c_resume(struct i2c_handle_s *hi2c)
1470 {
1471 	if (hi2c->i2c_state == I2C_STATE_READY)
1472 		return;
1473 
1474 	if ((hi2c->i2c_state != I2C_STATE_RESET) &&
1475 	    (hi2c->i2c_state != I2C_STATE_SUSPENDED))
1476 		panic();
1477 
1478 	stm32_pinctrl_load_active_cfg(hi2c->pinctrl, hi2c->pinctrl_count);
1479 
1480 	if (hi2c->i2c_state == I2C_STATE_RESET) {
1481 		/* There is no valid I2C configuration to be loaded yet */
1482 		return;
1483 	}
1484 
1485 	restore_cfg(hi2c, &hi2c->sec_cfg);
1486 
1487 	hi2c->i2c_state = I2C_STATE_READY;
1488 }
1489 
1490 void stm32_i2c_suspend(struct i2c_handle_s *hi2c)
1491 {
1492 	if (hi2c->i2c_state == I2C_STATE_SUSPENDED)
1493 		return;
1494 
1495 	if (hi2c->i2c_state != I2C_STATE_READY)
1496 		panic();
1497 
1498 	save_cfg(hi2c, &hi2c->sec_cfg);
1499 	stm32_pinctrl_load_standby_cfg(hi2c->pinctrl, hi2c->pinctrl_count);
1500 
1501 	hi2c->i2c_state = I2C_STATE_SUSPENDED;
1502 }
1503