xref: /optee_os/core/drivers/stm32_i2c.c (revision 41e5aa8f18c4d48083341ff3df9e75f0c77cf703)
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		25U
158 
159 #define CR2_RESET_MASK			(I2C_CR2_SADD | I2C_CR2_HEAD10R | \
160 					 I2C_CR2_NBYTES | I2C_CR2_RELOAD | \
161 					 I2C_CR2_RD_WRN)
162 
163 #define TIMINGR_CLEAR_MASK		(I2C_TIMINGR_SCLL | I2C_TIMINGR_SCLH | \
164 					 I2C_TIMINGR_SDADEL | \
165 					 I2C_TIMINGR_SCLDEL | I2C_TIMINGR_PRESC)
166 
167 /*
168  * I2C transfer modes
169  * I2C_RELOAD: Enable Reload mode
170  * I2C_AUTOEND_MODE: Enable automatic end mode
171  * I2C_SOFTEND_MODE: Enable software end mode
172  */
173 #define I2C_RELOAD_MODE				I2C_CR2_RELOAD
174 #define I2C_AUTOEND_MODE			I2C_CR2_AUTOEND
175 #define I2C_SOFTEND_MODE			0x0
176 
177 /*
178  * Start/restart/stop I2C transfer requests.
179  *
180  * I2C_NO_STARTSTOP: Don't Generate stop and start condition
181  * I2C_GENERATE_STOP: Generate stop condition (size should be set to 0)
182  * I2C_GENERATE_START_READ: Generate Restart for read request.
183  * I2C_GENERATE_START_WRITE: Generate Restart for write request
184  */
185 #define I2C_NO_STARTSTOP			0x0
186 #define I2C_GENERATE_STOP			(BIT(31) | I2C_CR2_STOP)
187 #define I2C_GENERATE_START_READ			(BIT(31) | I2C_CR2_START | \
188 						 I2C_CR2_RD_WRN)
189 #define I2C_GENERATE_START_WRITE		(BIT(31) | I2C_CR2_START)
190 
191 /* Memory address byte sizes */
192 #define I2C_MEMADD_SIZE_8BIT		1
193 #define I2C_MEMADD_SIZE_16BIT		2
194 
195 /*
196  * struct i2c_spec_s - Private I2C timing specifications.
197  * @rate: I2C bus speed (Hz)
198  * @rate_min: 80% of I2C bus speed (Hz)
199  * @rate_max: 120% of I2C bus speed (Hz)
200  * @fall_max: Max fall time of both SDA and SCL signals (ns)
201  * @rise_max: Max rise time of both SDA and SCL signals (ns)
202  * @hddat_min: Min data hold time (ns)
203  * @vddat_max: Max data valid time (ns)
204  * @sudat_min: Min data setup time (ns)
205  * @l_min: Min low period of the SCL clock (ns)
206  * @h_min: Min high period of the SCL clock (ns)
207  */
208 struct i2c_spec_s {
209 	uint32_t rate;
210 	uint32_t rate_min;
211 	uint32_t rate_max;
212 	uint32_t fall_max;
213 	uint32_t rise_max;
214 	uint32_t hddat_min;
215 	uint32_t vddat_max;
216 	uint32_t sudat_min;
217 	uint32_t l_min;
218 	uint32_t h_min;
219 };
220 
221 /*
222  * struct i2c_timing_s - Private I2C output parameters.
223  * @scldel: Data setup time
224  * @sdadel: Data hold time
225  * @sclh: SCL high period (master mode)
226  * @sclh: SCL low period (master mode)
227  * @is_saved: True if relating to a configuration candidate
228  */
229 struct i2c_timing_s {
230 	uint8_t scldel;
231 	uint8_t sdadel;
232 	uint8_t sclh;
233 	uint8_t scll;
234 	bool is_saved;
235 };
236 
237 static const struct i2c_spec_s i2c_specs[] = {
238 	[I2C_SPEED_STANDARD] = {
239 		.rate = I2C_STANDARD_RATE,
240 		.rate_min = (I2C_STANDARD_RATE * 80) / 100,
241 		.rate_max = (I2C_STANDARD_RATE * 120) / 100,
242 		.fall_max = 300,
243 		.rise_max = 1000,
244 		.hddat_min = 0,
245 		.vddat_max = 3450,
246 		.sudat_min = 250,
247 		.l_min = 4700,
248 		.h_min = 4000,
249 	},
250 	[I2C_SPEED_FAST] = {
251 		.rate = I2C_FAST_RATE,
252 		.rate_min = (I2C_FAST_RATE * 80) / 100,
253 		.rate_max = (I2C_FAST_RATE * 120) / 100,
254 		.fall_max = 300,
255 		.rise_max = 300,
256 		.hddat_min = 0,
257 		.vddat_max = 900,
258 		.sudat_min = 100,
259 		.l_min = 1300,
260 		.h_min = 600,
261 	},
262 	[I2C_SPEED_FAST_PLUS] = {
263 		.rate = I2C_FAST_PLUS_RATE,
264 		.rate_min = (I2C_FAST_PLUS_RATE * 80) / 100,
265 		.rate_max = (I2C_FAST_PLUS_RATE * 120) / 100,
266 		.fall_max = 100,
267 		.rise_max = 120,
268 		.hddat_min = 0,
269 		.vddat_max = 450,
270 		.sudat_min = 50,
271 		.l_min = 500,
272 		.h_min = 260,
273 	},
274 };
275 
276 /*
277  * I2C request parameters
278  * @dev_addr: I2C address of the target device
279  * @mode: Communication mode, one of I2C_MODE_(MASTER|MEM)
280  * @mem_addr: Target memory cell accessed in device (memory mode)
281  * @mem_addr_size: Byte size of the memory cell address (memory mode)
282  * @timeout_ms: Timeout in millisenconds for the request
283  */
284 struct i2c_request {
285 	uint32_t dev_addr;
286 	enum i2c_mode_e mode;
287 	uint32_t mem_addr;
288 	uint32_t mem_addr_size;
289 	unsigned int timeout_ms;
290 };
291 
292 static vaddr_t get_base(struct i2c_handle_s *hi2c)
293 {
294 	return io_pa_or_va_secure(&hi2c->base);
295 }
296 
297 static void notif_i2c_timeout(struct i2c_handle_s *hi2c)
298 {
299 	hi2c->i2c_err |= I2C_ERROR_TIMEOUT;
300 	hi2c->i2c_state = I2C_STATE_READY;
301 }
302 
303 static void save_cfg(struct i2c_handle_s *hi2c, struct i2c_cfg *cfg)
304 {
305 	vaddr_t base = get_base(hi2c);
306 
307 	stm32_clock_enable(hi2c->clock);
308 
309 	cfg->cr1 = io_read32(base + I2C_CR1);
310 	cfg->cr2 = io_read32(base + I2C_CR2);
311 	cfg->oar1 = io_read32(base + I2C_OAR1);
312 	cfg->oar2 = io_read32(base + I2C_OAR2);
313 	cfg->timingr = io_read32(base + I2C_TIMINGR);
314 
315 	stm32_clock_disable(hi2c->clock);
316 }
317 
318 static void restore_cfg(struct i2c_handle_s *hi2c, struct i2c_cfg *cfg)
319 {
320 	vaddr_t base = get_base(hi2c);
321 
322 	stm32_clock_enable(hi2c->clock);
323 
324 	io_clrbits32(base + I2C_CR1, I2C_CR1_PE);
325 	io_write32(base + I2C_TIMINGR, cfg->timingr & TIMINGR_CLEAR_MASK);
326 	io_write32(base + I2C_OAR1, cfg->oar1);
327 	io_write32(base + I2C_CR2, cfg->cr2);
328 	io_write32(base + I2C_OAR2, cfg->oar2);
329 	io_write32(base + I2C_CR1, cfg->cr1 & ~I2C_CR1_PE);
330 	io_setbits32(base + I2C_CR1, cfg->cr1 & I2C_CR1_PE);
331 
332 	stm32_clock_disable(hi2c->clock);
333 }
334 
335 static void __maybe_unused dump_cfg(struct i2c_cfg *cfg __maybe_unused)
336 {
337 	DMSG("CR1:  0x%" PRIx32, cfg->cr1);
338 	DMSG("CR2:  0x%" PRIx32, cfg->cr2);
339 	DMSG("OAR1: 0x%" PRIx32, cfg->oar1);
340 	DMSG("OAR2: 0x%" PRIx32, cfg->oar2);
341 	DMSG("TIM:  0x%" PRIx32, cfg->timingr);
342 }
343 
344 static void __maybe_unused dump_i2c(struct i2c_handle_s *hi2c)
345 {
346 	vaddr_t __maybe_unused base = get_base(hi2c);
347 
348 	stm32_clock_enable(hi2c->clock);
349 
350 	DMSG("CR1:  0x%" PRIx32, io_read32(base + I2C_CR1));
351 	DMSG("CR2:  0x%" PRIx32, io_read32(base + I2C_CR2));
352 	DMSG("OAR1: 0x%" PRIx32, io_read32(base + I2C_OAR1));
353 	DMSG("OAR2: 0x%" PRIx32, io_read32(base + I2C_OAR2));
354 	DMSG("TIM:  0x%" PRIx32, io_read32(base + I2C_TIMINGR));
355 
356 	stm32_clock_disable(hi2c->clock);
357 }
358 
359 /*
360  * Compute the I2C device timings
361  *
362  * @init: Ref to the initialization configuration structure
363  * @clock_src: I2C clock source frequency (Hz)
364  * @timing: Pointer to the final computed timing result
365  * Return 0 on success or a negative value
366  */
367 static int i2c_compute_timing(struct stm32_i2c_init_s *init,
368 			      uint32_t clock_src, uint32_t *timing)
369 {
370 	enum i2c_speed_e mode = init->speed_mode;
371 	uint32_t speed_freq = i2c_specs[mode].rate;
372 	uint32_t i2cbus = UDIV_ROUND_NEAREST(I2C_NSEC_PER_SEC, speed_freq);
373 	uint32_t i2cclk = UDIV_ROUND_NEAREST(I2C_NSEC_PER_SEC, clock_src);
374 	uint32_t p_prev = I2C_TIMINGR_PRESC_MAX;
375 	uint32_t af_delay_min = 0;
376 	uint32_t af_delay_max = 0;
377 	uint32_t dnf_delay = 0;
378 	uint32_t tsync = 0;
379 	uint32_t clk_min = 0;
380 	uint32_t clk_max = 0;
381 	int clk_error_prev = 0;
382 	uint16_t p = 0;
383 	uint16_t l = 0;
384 	uint16_t a = 0;
385 	uint16_t h = 0;
386 	unsigned int sdadel_min = 0;
387 	unsigned int sdadel_max = 0;
388 	unsigned int scldel_min = 0;
389 	unsigned int delay = 0;
390 	int s = -1;
391 	struct i2c_timing_s solutions[I2C_TIMINGR_PRESC_MAX] = { 0 };
392 
393 	switch (mode) {
394 	case I2C_SPEED_STANDARD:
395 	case I2C_SPEED_FAST:
396 	case I2C_SPEED_FAST_PLUS:
397 		break;
398 	default:
399 		EMSG("I2C speed out of bound {%d/%d}",
400 		     mode, I2C_SPEED_FAST_PLUS);
401 		return -1;
402 	}
403 
404 	speed_freq = i2c_specs[mode].rate;
405 	i2cbus = UDIV_ROUND_NEAREST(I2C_NSEC_PER_SEC, speed_freq);
406 	clk_error_prev = INT_MAX;
407 
408 	if ((init->rise_time > i2c_specs[mode].rise_max) ||
409 	    (init->fall_time > i2c_specs[mode].fall_max)) {
410 		EMSG(" I2C timings out of bound: Rise{%d > %d}/Fall{%d > %d}",
411 		     init->rise_time, i2c_specs[mode].rise_max,
412 		     init->fall_time, i2c_specs[mode].fall_max);
413 		return -1;
414 	}
415 
416 	if (init->digital_filter_coef > STM32_I2C_DIGITAL_FILTER_MAX) {
417 		EMSG("DNF out of bound %d/%d",
418 		     init->digital_filter_coef, STM32_I2C_DIGITAL_FILTER_MAX);
419 		return -1;
420 	}
421 
422 	/* Analog and Digital Filters */
423 	if (init->analog_filter) {
424 		af_delay_min = STM32_I2C_ANALOG_FILTER_DELAY_MIN;
425 		af_delay_max = STM32_I2C_ANALOG_FILTER_DELAY_MAX;
426 	}
427 	dnf_delay = init->digital_filter_coef * i2cclk;
428 
429 	sdadel_min = i2c_specs[mode].hddat_min + init->fall_time;
430 	delay = af_delay_min - ((init->digital_filter_coef + 3) * i2cclk);
431 	if (SUB_OVERFLOW(sdadel_min, delay, &sdadel_min))
432 		sdadel_min = 0;
433 
434 	sdadel_max = i2c_specs[mode].vddat_max - init->rise_time;
435 	delay = af_delay_max - ((init->digital_filter_coef + 4) * i2cclk);
436 	if (SUB_OVERFLOW(sdadel_max, delay, &sdadel_max))
437 		sdadel_max = 0;
438 
439 	scldel_min = init->rise_time + i2c_specs[mode].sudat_min;
440 
441 	DMSG("I2C SDADEL(min/max): %u/%u, SCLDEL(Min): %u",
442 	     sdadel_min, sdadel_max, scldel_min);
443 
444 	/* Compute possible values for PRESC, SCLDEL and SDADEL */
445 	for (p = 0; p < I2C_TIMINGR_PRESC_MAX; p++) {
446 		for (l = 0; l < I2C_TIMINGR_SCLDEL_MAX; l++) {
447 			uint32_t scldel = (l + 1) * (p + 1) * i2cclk;
448 
449 			if (scldel < scldel_min)
450 				continue;
451 
452 			for (a = 0; a < I2C_TIMINGR_SDADEL_MAX; a++) {
453 				uint32_t sdadel = (a * (p + 1) + 1) * i2cclk;
454 
455 				if ((sdadel >= sdadel_min) &&
456 				    (sdadel <= sdadel_max) &&
457 				    (p != p_prev)) {
458 					solutions[p].scldel = l;
459 					solutions[p].sdadel = a;
460 					solutions[p].is_saved = true;
461 					p_prev = p;
462 					break;
463 				}
464 			}
465 
466 			if (p_prev == p)
467 				break;
468 		}
469 	}
470 
471 	if (p_prev == I2C_TIMINGR_PRESC_MAX) {
472 		EMSG(" I2C no Prescaler solution");
473 		return -1;
474 	}
475 
476 	tsync = af_delay_min + dnf_delay + (2 * i2cclk);
477 	clk_max = I2C_NSEC_PER_SEC / i2c_specs[mode].rate_min;
478 	clk_min = I2C_NSEC_PER_SEC / i2c_specs[mode].rate_max;
479 
480 	/*
481 	 * Among prescaler possibilities discovered above figures out SCL Low
482 	 * and High Period. Provided:
483 	 * - SCL Low Period has to be higher than Low Period of the SCL Clock
484 	 *   defined by I2C Specification. I2C Clock has to be lower than
485 	 *   (SCL Low Period - Analog/Digital filters) / 4.
486 	 * - SCL High Period has to be lower than High Period of the SCL Clock
487 	 *   defined by I2C Specification.
488 	 * - I2C Clock has to be lower than SCL High Period.
489 	 */
490 	for (p = 0; p < I2C_TIMINGR_PRESC_MAX; p++) {
491 		uint32_t prescaler = (p + 1) * i2cclk;
492 
493 		if (!solutions[p].is_saved)
494 			continue;
495 
496 		for (l = 0; l < I2C_TIMINGR_SCLL_MAX; l++) {
497 			uint32_t tscl_l = ((l + 1) * prescaler) + tsync;
498 
499 			if ((tscl_l < i2c_specs[mode].l_min) ||
500 			    (i2cclk >=
501 			     ((tscl_l - af_delay_min - dnf_delay) / 4)))
502 				continue;
503 
504 			for (h = 0; h < I2C_TIMINGR_SCLH_MAX; h++) {
505 				uint32_t tscl_h = ((h + 1) * prescaler) + tsync;
506 				uint32_t tscl = tscl_l + tscl_h +
507 						init->rise_time +
508 						init->fall_time;
509 
510 				if ((tscl >= clk_min) && (tscl <= clk_max) &&
511 				    (tscl_h >= i2c_specs[mode].h_min) &&
512 				    (i2cclk < tscl_h)) {
513 					int clk_error = tscl - i2cbus;
514 
515 					if (clk_error < 0)
516 						clk_error = -clk_error;
517 
518 					if (clk_error < clk_error_prev) {
519 						clk_error_prev = clk_error;
520 						solutions[p].scll = l;
521 						solutions[p].sclh = h;
522 						s = p;
523 					}
524 				}
525 			}
526 		}
527 	}
528 
529 	if (s < 0) {
530 		EMSG(" I2C no solution at all");
531 		return -1;
532 	}
533 
534 	/* Finalize timing settings */
535 	*timing = I2C_SET_TIMINGR_PRESC(s) |
536 		   I2C_SET_TIMINGR_SCLDEL(solutions[s].scldel) |
537 		   I2C_SET_TIMINGR_SDADEL(solutions[s].sdadel) |
538 		   I2C_SET_TIMINGR_SCLH(solutions[s].sclh) |
539 		   I2C_SET_TIMINGR_SCLL(solutions[s].scll);
540 
541 	DMSG("I2C TIMINGR (PRESC/SCLDEL/SDADEL): %i/%i/%i",
542 		s, solutions[s].scldel, solutions[s].sdadel);
543 	DMSG("I2C TIMINGR (SCLH/SCLL): %i/%i",
544 		solutions[s].sclh, solutions[s].scll);
545 	DMSG("I2C TIMINGR: 0x%x", *timing);
546 
547 	return 0;
548 }
549 
550 /*
551  * Setup the I2C device timings
552  *
553  * @hi2c: I2C handle structure
554  * @init: Ref to the initialization configuration structure
555  * @timing: Output TIMINGR register configuration value
556  * @retval 0 if OK, negative value else
557  */
558 static int i2c_setup_timing(struct i2c_handle_s *hi2c,
559 			    struct stm32_i2c_init_s *init,
560 			    uint32_t *timing)
561 {
562 	int rc = 0;
563 	uint32_t clock_src = stm32_clock_get_rate(hi2c->clock);
564 
565 	if (!clock_src) {
566 		EMSG("Null I2C clock rate");
567 		return -1;
568 	}
569 
570 	do {
571 		rc = i2c_compute_timing(init, clock_src, timing);
572 		if (rc) {
573 			EMSG("Failed to compute I2C timings");
574 			if (init->speed_mode > I2C_SPEED_STANDARD) {
575 				init->speed_mode--;
576 				IMSG("Downgrade I2C speed to %uHz)",
577 				     i2c_specs[init->speed_mode].rate);
578 			} else {
579 				break;
580 			}
581 		}
582 	} while (rc);
583 
584 	if (rc) {
585 		EMSG("Impossible to compute I2C timings");
586 		return rc;
587 	}
588 
589 	DMSG("I2C Speed Mode(%i), Freq(%i), Clk Source(%i)",
590 	     init->speed_mode, i2c_specs[init->speed_mode].rate, clock_src);
591 	DMSG("I2C Rise(%i) and Fall(%i) Time",
592 	     init->rise_time, init->fall_time);
593 	DMSG("I2C Analog Filter(%s), DNF(%i)",
594 	     init->analog_filter ? "On" : "Off", init->digital_filter_coef);
595 
596 	return 0;
597 }
598 
599 /*
600  * Configure I2C Analog noise filter.
601  * @hi2c: I2C handle structure
602  * @analog_filter_on: True if enabling analog filter, false otherwise
603  * Return 0 on success or a negative value
604  */
605 static int i2c_config_analog_filter(struct i2c_handle_s *hi2c,
606 				    bool analog_filter_on)
607 {
608 	vaddr_t base = get_base(hi2c);
609 
610 	if (hi2c->i2c_state != I2C_STATE_READY)
611 		return -1;
612 
613 	hi2c->i2c_state = I2C_STATE_BUSY;
614 
615 	/* Disable the selected I2C peripheral */
616 	io_clrbits32(base + I2C_CR1, I2C_CR1_PE);
617 
618 	/* Reset I2Cx ANOFF bit */
619 	io_clrbits32(base + I2C_CR1, I2C_CR1_ANFOFF);
620 
621 	/* Set analog filter bit if filter is disabled */
622 	if (!analog_filter_on)
623 		io_setbits32(base + I2C_CR1, I2C_CR1_ANFOFF);
624 
625 	/* Enable the selected I2C peripheral */
626 	io_setbits32(base + I2C_CR1, I2C_CR1_PE);
627 
628 	hi2c->i2c_state = I2C_STATE_READY;
629 
630 	return 0;
631 }
632 
633 int stm32_i2c_get_setup_from_fdt(void *fdt, int node,
634 				 struct stm32_i2c_init_s *init,
635 				 struct stm32_pinctrl **pinctrl,
636 				 size_t *pinctrl_count)
637 {
638 	const fdt32_t *cuint = NULL;
639 	struct dt_node_info info = { .status = 0 };
640 	int count = 0;
641 
642 	/* Default STM32 specific configs caller may need to overwrite */
643 	memset(init, 0, sizeof(*init));
644 
645 	_fdt_fill_device_info(fdt, &info, node);
646 	init->pbase = info.reg;
647 	init->clock = info.clock;
648 	assert(info.reg != DT_INFO_INVALID_REG &&
649 	       info.clock != DT_INFO_INVALID_CLOCK);
650 
651 	cuint = fdt_getprop(fdt, node, "i2c-scl-rising-time-ns", NULL);
652 	if (cuint)
653 		init->rise_time = fdt32_to_cpu(*cuint);
654 	else
655 		init->rise_time = STM32_I2C_RISE_TIME_DEFAULT;
656 
657 	cuint = fdt_getprop(fdt, node, "i2c-scl-falling-time-ns", NULL);
658 	if (cuint)
659 		init->fall_time = fdt32_to_cpu(*cuint);
660 	else
661 		init->fall_time = STM32_I2C_FALL_TIME_DEFAULT;
662 
663 	cuint = fdt_getprop(fdt, node, "clock-frequency", NULL);
664 	if (cuint) {
665 		switch (fdt32_to_cpu(*cuint)) {
666 		case I2C_STANDARD_RATE:
667 			init->speed_mode = I2C_SPEED_STANDARD;
668 			break;
669 		case I2C_FAST_RATE:
670 			init->speed_mode = I2C_SPEED_FAST;
671 			break;
672 		case I2C_FAST_PLUS_RATE:
673 			init->speed_mode = I2C_SPEED_FAST_PLUS;
674 			break;
675 		default:
676 			init->speed_mode = STM32_I2C_SPEED_DEFAULT;
677 			break;
678 		}
679 	} else {
680 		init->speed_mode = STM32_I2C_SPEED_DEFAULT;
681 	}
682 
683 	count = stm32_pinctrl_fdt_get_pinctrl(fdt, node, NULL, 0);
684 	if (count <= 0) {
685 		*pinctrl = NULL;
686 		*pinctrl_count = 0;
687 		return count;
688 	}
689 
690 	if (count > 2)
691 		panic("Too many PINCTRLs found");
692 
693 	*pinctrl = calloc(count, sizeof(**pinctrl));
694 	if (!*pinctrl)
695 		panic();
696 
697 	*pinctrl_count = stm32_pinctrl_fdt_get_pinctrl(fdt, node,
698 						       *pinctrl, count);
699 	assert(*pinctrl_count == (unsigned int)count);
700 
701 	return 0;
702 }
703 
704 int stm32_i2c_init(struct i2c_handle_s *hi2c,
705 		   struct stm32_i2c_init_s *init_data)
706 {
707 	int rc = 0;
708 	uint32_t timing = 0;
709 	vaddr_t base = 0;
710 	uint32_t val = 0;
711 
712 	hi2c->base.pa = init_data->pbase;
713 	hi2c->clock = init_data->clock;
714 
715 	rc = i2c_setup_timing(hi2c, init_data, &timing);
716 	if (rc)
717 		return rc;
718 
719 	stm32_clock_enable(hi2c->clock);
720 	base = get_base(hi2c);
721 	hi2c->i2c_state = I2C_STATE_BUSY;
722 
723 	/* Disable the selected I2C peripheral */
724 	io_clrbits32(base + I2C_CR1, I2C_CR1_PE);
725 
726 	/* Configure I2Cx: Frequency range */
727 	io_write32(base + I2C_TIMINGR, timing & TIMINGR_CLEAR_MASK);
728 
729 	/* Disable Own Address1 before set the Own Address1 configuration */
730 	io_write32(base + I2C_OAR1, 0);
731 
732 	/* Configure I2Cx: Own Address1 and ack own address1 mode */
733 	if (init_data->addr_mode_10b_not_7b)
734 		io_write32(base + I2C_OAR1,
735 			   I2C_OAR1_OA1EN | I2C_OAR1_OA1MODE |
736 			   init_data->own_address1);
737 	else
738 		io_write32(base + I2C_OAR1,
739 			   I2C_OAR1_OA1EN | init_data->own_address1);
740 
741 	/* Configure I2Cx: Addressing Master mode */
742 	io_write32(base + I2C_CR2, 0);
743 	if (init_data->addr_mode_10b_not_7b)
744 		io_setbits32(base + I2C_CR2, I2C_CR2_ADD10);
745 
746 	/*
747 	 * Enable the AUTOEND by default, and enable NACK
748 	 * (should be disabled only during Slave process).
749 	 */
750 	io_setbits32(base + I2C_CR2, I2C_CR2_AUTOEND | I2C_CR2_NACK);
751 
752 	/* Disable Own Address2 before set the Own Address2 configuration */
753 	io_write32(base + I2C_OAR2, 0);
754 
755 	/* Configure I2Cx: Dual mode and Own Address2 */
756 	if (init_data->dual_address_mode)
757 		io_write32(base + I2C_OAR2,
758 			   I2C_OAR2_OA2EN | init_data->own_address2 |
759 			   (init_data->own_address2_masks << 8));
760 
761 	/* Configure I2Cx: Generalcall and NoStretch mode */
762 	val = 0;
763 	if (init_data->general_call_mode)
764 		val |= I2C_CR1_GCEN;
765 	if (init_data->no_stretch_mode)
766 		val |= I2C_CR1_NOSTRETCH;
767 	io_write32(base + I2C_CR1, val);
768 
769 	/* Enable the selected I2C peripheral */
770 	io_setbits32(base + I2C_CR1, I2C_CR1_PE);
771 
772 	hi2c->i2c_err = I2C_ERROR_NONE;
773 	hi2c->i2c_state = I2C_STATE_READY;
774 
775 	rc = i2c_config_analog_filter(hi2c, init_data->analog_filter);
776 	if (rc)
777 		EMSG("I2C analog filter error %d", rc);
778 
779 	stm32_clock_disable(hi2c->clock);
780 
781 	return rc;
782 }
783 
784 /* I2C transmit (TX) data register flush sequence */
785 static void i2c_flush_txdr(struct i2c_handle_s *hi2c)
786 {
787 	vaddr_t base = get_base(hi2c);
788 
789 	/*
790 	 * If a pending TXIS flag is set,
791 	 * write a dummy data in TXDR to clear it.
792 	 */
793 	if (io_read32(base + I2C_ISR) & I2C_ISR_TXIS)
794 		io_write32(base + I2C_TXDR, 0);
795 
796 	/* Flush TX register if not empty */
797 	if ((io_read32(base + I2C_ISR) & I2C_ISR_TXE) == 0)
798 		io_setbits32(base + I2C_ISR, I2C_ISR_TXE);
799 }
800 
801 /*
802  * Wait for a single target I2C_ISR bit to reach an awaited value (0 or 1)
803  *
804  * @hi2c: I2C handle structure
805  * @bit_mask: Bit mask for the target single bit position to consider
806  * @awaited_value: Awaited value of the target bit in I2C_ISR, 0 or 1
807  * @timeout_ref: Expriation timeout reference
808  * Return 0 on success and a non-zero value on timeout
809  */
810 static int wait_isr_event(struct i2c_handle_s *hi2c, uint32_t bit_mask,
811 			  unsigned int awaited_value, uint64_t timeout_ref)
812 {
813 	vaddr_t isr = get_base(hi2c) + I2C_ISR;
814 
815 	assert(IS_POWER_OF_TWO(bit_mask) && !(awaited_value & ~1U));
816 
817 	/* May timeout while TEE thread is suspended */
818 	while (!timeout_elapsed(timeout_ref))
819 		if (!!(io_read32(isr) & bit_mask) == awaited_value)
820 			break;
821 
822 	if (!!(io_read32(isr) & bit_mask) == awaited_value)
823 		return 0;
824 
825 	notif_i2c_timeout(hi2c);
826 	return -1;
827 }
828 
829 /* Handle Acknowledge-Failed sequence detection during an I2C Communication */
830 static int i2c_ack_failed(struct i2c_handle_s *hi2c, uint64_t timeout_ref)
831 {
832 	vaddr_t base = get_base(hi2c);
833 
834 	if ((io_read32(base + I2C_ISR) & I2C_ISR_NACKF) == 0U)
835 		return 0;
836 
837 	/*
838 	 * Wait until STOP Flag is reset. Use polling method.
839 	 * AutoEnd should be initiate after AF.
840 	 * Timeout may elpased while TEE thread is suspended.
841 	 */
842 	while (!timeout_elapsed(timeout_ref))
843 		if (io_read32(base + I2C_ISR) & I2C_ISR_STOPF)
844 			break;
845 
846 	if ((io_read32(base + I2C_ISR) & I2C_ISR_STOPF) == 0) {
847 		notif_i2c_timeout(hi2c);
848 		return -1;
849 	}
850 
851 	io_write32(base + I2C_ICR, I2C_ISR_NACKF);
852 
853 	io_write32(base + I2C_ICR, I2C_ISR_STOPF);
854 
855 	i2c_flush_txdr(hi2c);
856 
857 	io_clrbits32(base + I2C_CR2, CR2_RESET_MASK);
858 
859 	hi2c->i2c_err |= I2C_ERROR_ACKF;
860 	hi2c->i2c_state = I2C_STATE_READY;
861 
862 	return -1;
863 }
864 
865 /* Wait TXIS bit is 1 in I2C_ISR register */
866 static int i2c_wait_txis(struct i2c_handle_s *hi2c, uint64_t timeout_ref)
867 {
868 	while (!timeout_elapsed(timeout_ref)) {
869 		if (io_read32(get_base(hi2c) + I2C_ISR) & I2C_ISR_TXIS)
870 			break;
871 		if (i2c_ack_failed(hi2c, timeout_ref))
872 			return -1;
873 	}
874 
875 	if (io_read32(get_base(hi2c) + I2C_ISR) & I2C_ISR_TXIS)
876 		return 0;
877 
878 	if (i2c_ack_failed(hi2c, timeout_ref))
879 		return -1;
880 
881 	notif_i2c_timeout(hi2c);
882 	return -1;
883 }
884 
885 /* Wait STOPF bit is 1 in I2C_ISR register */
886 static int i2c_wait_stop(struct i2c_handle_s *hi2c, uint64_t timeout_ref)
887 {
888 	while (!timeout_elapsed(timeout_ref)) {
889 		if (io_read32(get_base(hi2c) + I2C_ISR) & I2C_ISR_STOPF)
890 			break;
891 
892 		if (i2c_ack_failed(hi2c, timeout_ref))
893 			return -1;
894 	}
895 
896 	if (io_read32(get_base(hi2c) + I2C_ISR) & I2C_ISR_STOPF)
897 		return 0;
898 
899 	if (i2c_ack_failed(hi2c, timeout_ref))
900 		return -1;
901 
902 	notif_i2c_timeout(hi2c);
903 	return -1;
904 }
905 
906 /*
907  * Load I2C_CR2 register for a I2C transfer
908  *
909  * @hi2c: I2C handle structure
910  * @dev_addr: Slave address to be transferred
911  * @size: Number of bytes to be transferred
912  * @i2c_mode: One of I2C_{RELOAD|AUTOEND|SOFTEND}_MODE: Enable Reload mode.
913  * @startstop: One of I2C_NO_STARTSTOP, I2C_GENERATE_STOP,
914  *		I2C_GENERATE_START_{READ|WRITE}
915  */
916 static void i2c_transfer_config(struct i2c_handle_s *hi2c, uint32_t dev_addr,
917 				uint32_t size, uint32_t i2c_mode,
918 				uint32_t startstop)
919 {
920 	uint32_t clr_value = I2C_CR2_SADD | I2C_CR2_NBYTES | I2C_CR2_RELOAD |
921 			     I2C_CR2_AUTOEND | I2C_CR2_START | I2C_CR2_STOP |
922 			     (I2C_CR2_RD_WRN &
923 			      (startstop >> (31U - I2C_CR2_RD_WRN_OFFSET)));
924 	uint32_t set_value = (dev_addr & I2C_CR2_SADD) |
925 			     ((size << I2C_CR2_NBYTES_OFFSET) &
926 			      I2C_CR2_NBYTES) |
927 			     i2c_mode | startstop;
928 
929 	io_clrsetbits32(get_base(hi2c) + I2C_CR2, clr_value, set_value);
930 }
931 
932 /*
933  * Master sends target device address followed by internal memory
934  * address for a memory write request.
935  * Function returns 0 on success or a negative value.
936  */
937 static int i2c_request_mem_write(struct i2c_handle_s *hi2c,
938 				 struct i2c_request *request,
939 				 uint64_t timeout_ref)
940 {
941 	vaddr_t base = get_base(hi2c);
942 
943 	i2c_transfer_config(hi2c, request->dev_addr, request->mem_addr_size,
944 			    I2C_RELOAD_MODE, I2C_GENERATE_START_WRITE);
945 
946 	if (i2c_wait_txis(hi2c, timeout_ref))
947 		return -1;
948 
949 	if (request->mem_addr_size == I2C_MEMADD_SIZE_8BIT) {
950 		/* Send memory address */
951 		io_write8(base + I2C_TXDR, request->mem_addr & 0x00FFU);
952 	} else {
953 		/* Send MSB of memory address */
954 		io_write8(base + I2C_TXDR, (request->mem_addr & 0xFF00U) >> 8);
955 
956 		if (i2c_wait_txis(hi2c, timeout_ref))
957 			return -1;
958 
959 		/* Send LSB of memory address */
960 		io_write8(base + I2C_TXDR, request->mem_addr & 0x00FFU);
961 	}
962 
963 	if (wait_isr_event(hi2c, I2C_ISR_TCR, 1, timeout_ref))
964 		return -1;
965 
966 	return 0;
967 }
968 
969 /*
970  * Master sends target device address followed by internal memory
971  * address to prepare a memory read request.
972  * Function returns 0 on success or a negative value.
973  */
974 static int i2c_request_mem_read(struct i2c_handle_s *hi2c,
975 				struct i2c_request *request,
976 				uint64_t timeout_ref)
977 {
978 	vaddr_t base = get_base(hi2c);
979 
980 	i2c_transfer_config(hi2c, request->dev_addr, request->mem_addr_size,
981 			    I2C_SOFTEND_MODE, I2C_GENERATE_START_WRITE);
982 
983 	if (i2c_wait_txis(hi2c, timeout_ref))
984 		return -1;
985 
986 	if (request->mem_addr_size == I2C_MEMADD_SIZE_8BIT) {
987 		/* Send memory address */
988 		io_write8(base + I2C_TXDR, request->mem_addr & 0x00FFU);
989 	} else {
990 		/* Send MSB of memory address */
991 		io_write8(base + I2C_TXDR, (request->mem_addr & 0xFF00U) >> 8);
992 
993 		if (i2c_wait_txis(hi2c, timeout_ref))
994 			return -1;
995 
996 		/* Send LSB of memory address */
997 		io_write8(base + I2C_TXDR, request->mem_addr & 0x00FFU);
998 	}
999 
1000 	if (wait_isr_event(hi2c, I2C_ISR_TC, 1, timeout_ref))
1001 		return -1;
1002 
1003 	return 0;
1004 }
1005 
1006 /*
1007  * Write an amount of data in blocking mode
1008  *
1009  * @hi2c: Reference to struct i2c_handle_s
1010  * @request: I2C request parameters
1011  * @p_data: Pointer to data buffer
1012  * @size: Amount of data to be sent
1013  * Return 0 on success or a negative value
1014  */
1015 static int i2c_write(struct i2c_handle_s *hi2c, struct i2c_request *request,
1016 		     uint8_t *p_data, uint16_t size)
1017 {
1018 	uint64_t timeout_ref = 0;
1019 	vaddr_t base = get_base(hi2c);
1020 	int rc = -1;
1021 	uint8_t *p_buff = p_data;
1022 	size_t xfer_size = 0;
1023 	size_t xfer_count = size;
1024 
1025 	if (request->mode != I2C_MODE_MASTER && request->mode != I2C_MODE_MEM)
1026 		return -1;
1027 
1028 	if (hi2c->i2c_state != I2C_STATE_READY)
1029 		return -1;
1030 
1031 	if (!p_data || !size)
1032 		return -1;
1033 
1034 	stm32_clock_enable(hi2c->clock);
1035 
1036 	timeout_ref = timeout_init_us(I2C_TIMEOUT_BUSY_MS * 1000);
1037 	if (wait_isr_event(hi2c, I2C_ISR_BUSY, 0, timeout_ref))
1038 		goto bail;
1039 
1040 	hi2c->i2c_state = I2C_STATE_BUSY_TX;
1041 	hi2c->i2c_err = I2C_ERROR_NONE;
1042 	timeout_ref = timeout_init_us(request->timeout_ms * 1000);
1043 
1044 	if (request->mode == I2C_MODE_MEM) {
1045 		/* In memory mode, send slave address and memory address */
1046 		if (i2c_request_mem_write(hi2c, request, timeout_ref))
1047 			goto bail;
1048 
1049 		if (xfer_count > MAX_NBYTE_SIZE) {
1050 			xfer_size = MAX_NBYTE_SIZE;
1051 			i2c_transfer_config(hi2c, request->dev_addr, xfer_size,
1052 					    I2C_RELOAD_MODE, I2C_NO_STARTSTOP);
1053 		} else {
1054 			xfer_size = xfer_count;
1055 			i2c_transfer_config(hi2c, request->dev_addr, xfer_size,
1056 					    I2C_AUTOEND_MODE, I2C_NO_STARTSTOP);
1057 		}
1058 	} else {
1059 		/* In master mode, send slave address */
1060 		if (xfer_count > MAX_NBYTE_SIZE) {
1061 			xfer_size = MAX_NBYTE_SIZE;
1062 			i2c_transfer_config(hi2c, request->dev_addr, xfer_size,
1063 					    I2C_RELOAD_MODE,
1064 					    I2C_GENERATE_START_WRITE);
1065 		} else {
1066 			xfer_size = xfer_count;
1067 			i2c_transfer_config(hi2c, request->dev_addr, xfer_size,
1068 					    I2C_AUTOEND_MODE,
1069 					    I2C_GENERATE_START_WRITE);
1070 		}
1071 	}
1072 
1073 	do {
1074 		if (i2c_wait_txis(hi2c, timeout_ref))
1075 			goto bail;
1076 
1077 		io_write8(base + I2C_TXDR, *p_buff);
1078 		p_buff++;
1079 		xfer_count--;
1080 		xfer_size--;
1081 
1082 		if (xfer_count && !xfer_size) {
1083 			/* Wait until TCR flag is set */
1084 			if (wait_isr_event(hi2c, I2C_ISR_TCR, 1, timeout_ref))
1085 				goto bail;
1086 
1087 			if (xfer_count > MAX_NBYTE_SIZE) {
1088 				xfer_size = MAX_NBYTE_SIZE;
1089 				i2c_transfer_config(hi2c, request->dev_addr,
1090 						    xfer_size,
1091 						    I2C_RELOAD_MODE,
1092 						    I2C_NO_STARTSTOP);
1093 			} else {
1094 				xfer_size = xfer_count;
1095 				i2c_transfer_config(hi2c, request->dev_addr,
1096 						    xfer_size,
1097 						    I2C_AUTOEND_MODE,
1098 						    I2C_NO_STARTSTOP);
1099 			}
1100 		}
1101 
1102 	} while (xfer_count > 0U);
1103 
1104 	/*
1105 	 * No need to Check TC flag, with AUTOEND mode the stop
1106 	 * is automatically generated.
1107 	 * Wait until STOPF flag is reset.
1108 	 */
1109 	if (i2c_wait_stop(hi2c, timeout_ref))
1110 		goto bail;
1111 
1112 	io_write32(base + I2C_ICR, I2C_ISR_STOPF);
1113 
1114 	io_clrbits32(base + I2C_CR2, CR2_RESET_MASK);
1115 
1116 	hi2c->i2c_state = I2C_STATE_READY;
1117 
1118 	rc = 0;
1119 
1120 bail:
1121 	stm32_clock_disable(hi2c->clock);
1122 
1123 	return rc;
1124 }
1125 
1126 int stm32_i2c_mem_write(struct i2c_handle_s *hi2c, uint32_t dev_addr,
1127 			uint32_t mem_addr, uint32_t mem_addr_size,
1128 			uint8_t *p_data, size_t size, unsigned int timeout_ms)
1129 {
1130 	struct i2c_request request = {
1131 		.dev_addr = dev_addr,
1132 		.mode = I2C_MODE_MEM,
1133 		.mem_addr = mem_addr,
1134 		.mem_addr_size = mem_addr_size,
1135 		.timeout_ms = timeout_ms,
1136 	};
1137 
1138 	return i2c_write(hi2c, &request, p_data, size);
1139 }
1140 
1141 int stm32_i2c_master_transmit(struct i2c_handle_s *hi2c, uint32_t dev_addr,
1142 			      uint8_t *p_data, size_t size,
1143 			      unsigned int timeout_ms)
1144 {
1145 	struct i2c_request request = {
1146 		.dev_addr = dev_addr,
1147 		.mode = I2C_MODE_MASTER,
1148 		.timeout_ms = timeout_ms,
1149 	};
1150 
1151 	return i2c_write(hi2c, &request, p_data, size);
1152 }
1153 
1154 /*
1155  * Read an amount of data in blocking mode
1156  *
1157  * @hi2c: Reference to struct i2c_handle_s
1158  * @request: I2C request parameters
1159  * @p_data: Pointer to data buffer
1160  * @size: Amount of data to be sent
1161  * Return 0 on success or a negative value
1162  */
1163 static int i2c_read(struct i2c_handle_s *hi2c, struct i2c_request *request,
1164 		    uint8_t *p_data, uint32_t size)
1165 {
1166 	vaddr_t base = get_base(hi2c);
1167 	uint64_t timeout_ref = 0;
1168 	int rc = -1;
1169 	uint8_t *p_buff = p_data;
1170 	size_t xfer_count = size;
1171 	size_t xfer_size = 0;
1172 
1173 	if (request->mode != I2C_MODE_MASTER && request->mode != I2C_MODE_MEM)
1174 		return -1;
1175 
1176 	if (hi2c->i2c_state != I2C_STATE_READY)
1177 		return -1;
1178 
1179 	if (!p_data || !size)
1180 		return -1;
1181 
1182 	stm32_clock_enable(hi2c->clock);
1183 
1184 	timeout_ref = timeout_init_us(I2C_TIMEOUT_BUSY_MS * 1000);
1185 	if (wait_isr_event(hi2c, I2C_ISR_BUSY, 0, timeout_ref))
1186 		goto bail;
1187 
1188 	hi2c->i2c_state = I2C_STATE_BUSY_RX;
1189 	hi2c->i2c_err = I2C_ERROR_NONE;
1190 	timeout_ref = timeout_init_us(request->timeout_ms * 1000);
1191 
1192 	if (request->mode == I2C_MODE_MEM) {
1193 		/* Send memory address */
1194 		if (i2c_request_mem_read(hi2c, request, timeout_ref))
1195 			goto bail;
1196 	}
1197 
1198 	/*
1199 	 * Send slave address.
1200 	 * Set NBYTES to write and reload if xfer_count > MAX_NBYTE_SIZE
1201 	 * and generate RESTART.
1202 	 */
1203 	if (xfer_count > MAX_NBYTE_SIZE) {
1204 		xfer_size = MAX_NBYTE_SIZE;
1205 		i2c_transfer_config(hi2c, request->dev_addr, xfer_size,
1206 				    I2C_RELOAD_MODE, I2C_GENERATE_START_READ);
1207 	} else {
1208 		xfer_size = xfer_count;
1209 		i2c_transfer_config(hi2c, request->dev_addr, xfer_size,
1210 				    I2C_AUTOEND_MODE, I2C_GENERATE_START_READ);
1211 	}
1212 
1213 	do {
1214 		if (wait_isr_event(hi2c, I2C_ISR_RXNE, 1, timeout_ref))
1215 			goto bail;
1216 
1217 		*p_buff = io_read8(base + I2C_RXDR);
1218 		p_buff++;
1219 		xfer_size--;
1220 		xfer_count--;
1221 
1222 		if (xfer_count && !xfer_size) {
1223 			if (wait_isr_event(hi2c, I2C_ISR_TCR, 1, timeout_ref))
1224 				goto bail;
1225 
1226 			if (xfer_count > MAX_NBYTE_SIZE) {
1227 				xfer_size = MAX_NBYTE_SIZE;
1228 				i2c_transfer_config(hi2c, request->dev_addr,
1229 						    xfer_size,
1230 						    I2C_RELOAD_MODE,
1231 						    I2C_NO_STARTSTOP);
1232 			} else {
1233 				xfer_size = xfer_count;
1234 				i2c_transfer_config(hi2c, request->dev_addr,
1235 						    xfer_size,
1236 						    I2C_AUTOEND_MODE,
1237 						    I2C_NO_STARTSTOP);
1238 			}
1239 		}
1240 	} while (xfer_count > 0U);
1241 
1242 	/*
1243 	 * No need to Check TC flag, with AUTOEND mode the stop
1244 	 * is automatically generated.
1245 	 * Wait until STOPF flag is reset.
1246 	 */
1247 	if (i2c_wait_stop(hi2c, timeout_ref))
1248 		goto bail;
1249 
1250 	io_write32(base + I2C_ICR, I2C_ISR_STOPF);
1251 
1252 	io_clrbits32(base + I2C_CR2, CR2_RESET_MASK);
1253 
1254 	hi2c->i2c_state = I2C_STATE_READY;
1255 
1256 	rc = 0;
1257 
1258 bail:
1259 	stm32_clock_disable(hi2c->clock);
1260 
1261 	return rc;
1262 }
1263 
1264 int stm32_i2c_mem_read(struct i2c_handle_s *hi2c, uint32_t dev_addr,
1265 		       uint32_t mem_addr, uint32_t mem_addr_size,
1266 		       uint8_t *p_data, size_t size, unsigned int timeout_ms)
1267 {
1268 	struct i2c_request request = {
1269 		.dev_addr = dev_addr,
1270 		.mode = I2C_MODE_MEM,
1271 		.mem_addr = mem_addr,
1272 		.mem_addr_size = mem_addr_size,
1273 		.timeout_ms = timeout_ms,
1274 	};
1275 
1276 	return i2c_read(hi2c, &request, p_data, size);
1277 }
1278 
1279 int stm32_i2c_master_receive(struct i2c_handle_s *hi2c, uint32_t dev_addr,
1280 			     uint8_t *p_data, size_t size,
1281 			     unsigned int timeout_ms)
1282 {
1283 	struct i2c_request request = {
1284 		.dev_addr = dev_addr,
1285 		.mode = I2C_MODE_MASTER,
1286 		.timeout_ms = timeout_ms,
1287 	};
1288 
1289 	return i2c_read(hi2c, &request, p_data, size);
1290 }
1291 
1292 bool stm32_i2c_is_device_ready(struct i2c_handle_s *hi2c, uint32_t dev_addr,
1293 			       unsigned int trials, unsigned int timeout_ms)
1294 {
1295 	vaddr_t base = get_base(hi2c);
1296 	unsigned int i2c_trials = 0U;
1297 	bool rc = false;
1298 
1299 	if (hi2c->i2c_state != I2C_STATE_READY)
1300 		return rc;
1301 
1302 	stm32_clock_enable(hi2c->clock);
1303 
1304 	if (io_read32(base + I2C_ISR) & I2C_ISR_BUSY)
1305 		goto bail;
1306 
1307 	hi2c->i2c_state = I2C_STATE_BUSY;
1308 	hi2c->i2c_err = I2C_ERROR_NONE;
1309 
1310 	do {
1311 		uint64_t timeout_ref = 0;
1312 		vaddr_t isr = base + I2C_ISR;
1313 
1314 		/* Generate Start */
1315 		if ((io_read32(base + I2C_OAR1) & I2C_OAR1_OA1MODE) == 0)
1316 			io_write32(base + I2C_CR2,
1317 				   ((dev_addr & I2C_CR2_SADD) |
1318 				    I2C_CR2_START | I2C_CR2_AUTOEND) &
1319 				   ~I2C_CR2_RD_WRN);
1320 		else
1321 			io_write32(base + I2C_CR2,
1322 				   ((dev_addr & I2C_CR2_SADD) |
1323 				    I2C_CR2_START | I2C_CR2_ADD10) &
1324 				   ~I2C_CR2_RD_WRN);
1325 
1326 		/*
1327 		 * No need to Check TC flag, with AUTOEND mode the stop
1328 		 * is automatically generated.
1329 		 * Wait until STOPF flag is set or a NACK flag is set.
1330 		 */
1331 		timeout_ref = timeout_init_us(timeout_ms * 1000);
1332 		while (!timeout_elapsed(timeout_ref))
1333 			if (io_read32(isr) & (I2C_ISR_STOPF | I2C_ISR_NACKF))
1334 				break;
1335 
1336 		if ((io_read32(isr) & (I2C_ISR_STOPF | I2C_ISR_NACKF)) == 0) {
1337 			notif_i2c_timeout(hi2c);
1338 			goto bail;
1339 		}
1340 
1341 		if ((io_read32(base + I2C_ISR) & I2C_ISR_NACKF) == 0U) {
1342 			if (wait_isr_event(hi2c, I2C_ISR_STOPF, 1, timeout_ref))
1343 				goto bail;
1344 
1345 			io_write32(base + I2C_ICR, I2C_ISR_STOPF);
1346 
1347 			hi2c->i2c_state = I2C_STATE_READY;
1348 
1349 			rc = true;
1350 			goto bail;
1351 		}
1352 
1353 		if (wait_isr_event(hi2c, I2C_ISR_STOPF, 1, timeout_ref))
1354 			goto bail;
1355 
1356 		io_write32(base + I2C_ICR, I2C_ISR_NACKF);
1357 		io_write32(base + I2C_ICR, I2C_ISR_STOPF);
1358 
1359 		if (i2c_trials == trials) {
1360 			io_setbits32(base + I2C_CR2, I2C_CR2_STOP);
1361 
1362 			if (wait_isr_event(hi2c, I2C_ISR_STOPF, 1, timeout_ref))
1363 				goto bail;
1364 
1365 			io_write32(base + I2C_ICR, I2C_ISR_STOPF);
1366 		}
1367 
1368 		i2c_trials++;
1369 	} while (i2c_trials < trials);
1370 
1371 	notif_i2c_timeout(hi2c);
1372 
1373 bail:
1374 	stm32_clock_disable(hi2c->clock);
1375 
1376 	return rc;
1377 }
1378 
1379 void stm32_i2c_resume(struct i2c_handle_s *hi2c)
1380 {
1381 	if (hi2c->i2c_state == I2C_STATE_READY)
1382 		return;
1383 
1384 	if ((hi2c->i2c_state != I2C_STATE_RESET) &&
1385 	    (hi2c->i2c_state != I2C_STATE_SUSPENDED))
1386 		panic();
1387 
1388 	stm32_pinctrl_load_active_cfg(hi2c->pinctrl, hi2c->pinctrl_count);
1389 
1390 	if (hi2c->i2c_state == I2C_STATE_RESET) {
1391 		/* There is no valid I2C configuration to be loaded yet */
1392 		return;
1393 	}
1394 
1395 	restore_cfg(hi2c, &hi2c->sec_cfg);
1396 
1397 	hi2c->i2c_state = I2C_STATE_READY;
1398 }
1399 
1400 void stm32_i2c_suspend(struct i2c_handle_s *hi2c)
1401 {
1402 	if (hi2c->i2c_state == I2C_STATE_SUSPENDED)
1403 		return;
1404 
1405 	if (hi2c->i2c_state != I2C_STATE_READY)
1406 		panic();
1407 
1408 	save_cfg(hi2c, &hi2c->sec_cfg);
1409 	stm32_pinctrl_load_standby_cfg(hi2c->pinctrl, hi2c->pinctrl_count);
1410 
1411 	hi2c->i2c_state = I2C_STATE_SUSPENDED;
1412 }
1413