xref: /optee_os/core/drivers/stm32_i2c.c (revision 87aead6ffab3e2a877c315c5f9d9aa1f57db1db2)
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/clk.h>
14 #include <drivers/clk_dt.h>
15 #include <drivers/pinctrl.h>
16 #include <drivers/stm32_gpio.h>
17 #include <drivers/stm32_i2c.h>
18 #include <io.h>
19 #include <kernel/delay.h>
20 #include <kernel/dt.h>
21 #include <kernel/dt_driver.h>
22 #include <kernel/boot.h>
23 #include <kernel/panic.h>
24 #include <libfdt.h>
25 #include <stdbool.h>
26 #include <stdlib.h>
27 #include <stm32_util.h>
28 #include <trace.h>
29 
30 /* STM32 I2C registers offsets */
31 #define I2C_CR1				0x00U
32 #define I2C_CR2				0x04U
33 #define I2C_OAR1			0x08U
34 #define I2C_OAR2			0x0CU
35 #define I2C_TIMINGR			0x10U
36 #define I2C_TIMEOUTR			0x14U
37 #define I2C_ISR				0x18U
38 #define I2C_ICR				0x1CU
39 #define I2C_PECR			0x20U
40 #define I2C_RXDR			0x24U
41 #define I2C_TXDR			0x28U
42 #define I2C_SIZE			0x2CU
43 
44 /* Bit definition for I2C_CR1 register */
45 #define I2C_CR1_PE			BIT(0)
46 #define I2C_CR1_TXIE			BIT(1)
47 #define I2C_CR1_RXIE			BIT(2)
48 #define I2C_CR1_ADDRIE			BIT(3)
49 #define I2C_CR1_NACKIE			BIT(4)
50 #define I2C_CR1_STOPIE			BIT(5)
51 #define I2C_CR1_TCIE			BIT(6)
52 #define I2C_CR1_ERRIE			BIT(7)
53 #define I2C_CR1_DNF			GENMASK_32(11, 8)
54 #define I2C_CR1_ANFOFF			BIT(12)
55 #define I2C_CR1_SWRST			BIT(13)
56 #define I2C_CR1_TXDMAEN			BIT(14)
57 #define I2C_CR1_RXDMAEN			BIT(15)
58 #define I2C_CR1_SBC			BIT(16)
59 #define I2C_CR1_NOSTRETCH		BIT(17)
60 #define I2C_CR1_WUPEN			BIT(18)
61 #define I2C_CR1_GCEN			BIT(19)
62 #define I2C_CR1_SMBHEN			BIT(22)
63 #define I2C_CR1_SMBDEN			BIT(21)
64 #define I2C_CR1_ALERTEN			BIT(22)
65 #define I2C_CR1_PECEN			BIT(23)
66 
67 /* Bit definition for I2C_CR2 register */
68 #define I2C_CR2_SADD			GENMASK_32(9, 0)
69 #define I2C_CR2_RD_WRN			BIT(10)
70 #define I2C_CR2_RD_WRN_OFFSET		10U
71 #define I2C_CR2_ADD10			BIT(11)
72 #define I2C_CR2_HEAD10R			BIT(12)
73 #define I2C_CR2_START			BIT(13)
74 #define I2C_CR2_STOP			BIT(14)
75 #define I2C_CR2_NACK			BIT(15)
76 #define I2C_CR2_NBYTES			GENMASK_32(23, 16)
77 #define I2C_CR2_NBYTES_OFFSET		16U
78 #define I2C_CR2_RELOAD			BIT(24)
79 #define I2C_CR2_AUTOEND			BIT(25)
80 #define I2C_CR2_PECBYTE			BIT(26)
81 
82 /* Bit definition for I2C_OAR1 register */
83 #define I2C_OAR1_OA1			GENMASK_32(9, 0)
84 #define I2C_OAR1_OA1MODE		BIT(10)
85 #define I2C_OAR1_OA1EN			BIT(15)
86 
87 /* Bit definition for I2C_OAR2 register */
88 #define I2C_OAR2_OA2			GENMASK_32(7, 1)
89 #define I2C_OAR2_OA2MSK			GENMASK_32(10, 8)
90 #define I2C_OAR2_OA2NOMASK		0
91 #define I2C_OAR2_OA2MASK01		BIT(8)
92 #define I2C_OAR2_OA2MASK02		BIT(9)
93 #define I2C_OAR2_OA2MASK03		GENMASK_32(9, 8)
94 #define I2C_OAR2_OA2MASK04		BIT(10)
95 #define I2C_OAR2_OA2MASK05		(BIT(8) | BIT(10))
96 #define I2C_OAR2_OA2MASK06		(BIT(9) | BIT(10))
97 #define I2C_OAR2_OA2MASK07		GENMASK_32(10, 8)
98 #define I2C_OAR2_OA2EN			BIT(15)
99 
100 /* Bit definition for I2C_TIMINGR register */
101 #define I2C_TIMINGR_SCLL		GENMASK_32(7, 0)
102 #define I2C_TIMINGR_SCLH		GENMASK_32(15, 8)
103 #define I2C_TIMINGR_SDADEL		GENMASK_32(19, 16)
104 #define I2C_TIMINGR_SCLDEL		GENMASK_32(23, 20)
105 #define I2C_TIMINGR_PRESC		GENMASK_32(31, 28)
106 #define I2C_TIMINGR_SCLL_MAX		(I2C_TIMINGR_SCLL + 1)
107 #define I2C_TIMINGR_SCLH_MAX		((I2C_TIMINGR_SCLH >> 8) + 1)
108 #define I2C_TIMINGR_SDADEL_MAX		((I2C_TIMINGR_SDADEL >> 16) + 1)
109 #define I2C_TIMINGR_SCLDEL_MAX		((I2C_TIMINGR_SCLDEL >> 20) + 1)
110 #define I2C_TIMINGR_PRESC_MAX		((I2C_TIMINGR_PRESC >> 28) + 1)
111 #define I2C_SET_TIMINGR_SCLL(n)		((n) & \
112 					 (I2C_TIMINGR_SCLL_MAX - 1))
113 #define I2C_SET_TIMINGR_SCLH(n)		(((n) & \
114 					  (I2C_TIMINGR_SCLH_MAX - 1)) << 8)
115 #define I2C_SET_TIMINGR_SDADEL(n)	(((n) & \
116 					  (I2C_TIMINGR_SDADEL_MAX - 1)) << 16)
117 #define I2C_SET_TIMINGR_SCLDEL(n)	(((n) & \
118 					  (I2C_TIMINGR_SCLDEL_MAX - 1)) << 20)
119 #define I2C_SET_TIMINGR_PRESC(n)	(((n) & \
120 					  (I2C_TIMINGR_PRESC_MAX - 1)) << 28)
121 
122 /* Bit definition for I2C_TIMEOUTR register */
123 #define I2C_TIMEOUTR_TIMEOUTA		GENMASK_32(11, 0)
124 #define I2C_TIMEOUTR_TIDLE		BIT(12)
125 #define I2C_TIMEOUTR_TIMOUTEN		BIT(15)
126 #define I2C_TIMEOUTR_TIMEOUTB		GENMASK_32(27, 16)
127 #define I2C_TIMEOUTR_TEXTEN		BIT(31)
128 
129 /* Bit definition for I2C_ISR register */
130 #define I2C_ISR_TXE			BIT(0)
131 #define I2C_ISR_TXIS			BIT(1)
132 #define I2C_ISR_RXNE			BIT(2)
133 #define I2C_ISR_ADDR			BIT(3)
134 #define I2C_ISR_NACKF			BIT(4)
135 #define I2C_ISR_STOPF			BIT(5)
136 #define I2C_ISR_TC			BIT(6)
137 #define I2C_ISR_TCR			BIT(7)
138 #define I2C_ISR_BERR			BIT(8)
139 #define I2C_ISR_ARLO			BIT(9)
140 #define I2C_ISR_OVR			BIT(10)
141 #define I2C_ISR_PECERR			BIT(11)
142 #define I2C_ISR_TIMEOUT			BIT(12)
143 #define I2C_ISR_ALERT			BIT(13)
144 #define I2C_ISR_BUSY			BIT(15)
145 #define I2C_ISR_DIR			BIT(16)
146 #define I2C_ISR_ADDCODE			GENMASK_32(23, 17)
147 
148 /* Bit definition for I2C_ICR register */
149 #define I2C_ICR_ADDRCF			BIT(3)
150 #define I2C_ICR_NACKCF			BIT(4)
151 #define I2C_ICR_STOPCF			BIT(5)
152 #define I2C_ICR_BERRCF			BIT(8)
153 #define I2C_ICR_ARLOCF			BIT(9)
154 #define I2C_ICR_OVRCF			BIT(10)
155 #define I2C_ICR_PECCF			BIT(11)
156 #define I2C_ICR_TIMOUTCF		BIT(12)
157 #define I2C_ICR_ALERTCF			BIT(13)
158 
159 /* Max data size for a single I2C transfer */
160 #define MAX_NBYTE_SIZE			255U
161 
162 #define I2C_NSEC_PER_SEC		1000000000UL
163 #define I2C_TIMEOUT_BUSY_MS		25
164 #define I2C_TIMEOUT_BUSY_US		(I2C_TIMEOUT_BUSY_MS * 1000)
165 #define I2C_TIMEOUT_RXNE_MS		5
166 
167 #define I2C_TIMEOUT_DEFAULT_MS		100
168 
169 #define CR2_RESET_MASK			(I2C_CR2_SADD | I2C_CR2_HEAD10R | \
170 					 I2C_CR2_NBYTES | I2C_CR2_RELOAD | \
171 					 I2C_CR2_RD_WRN)
172 
173 #define TIMINGR_CLEAR_MASK		(I2C_TIMINGR_SCLL | I2C_TIMINGR_SCLH | \
174 					 I2C_TIMINGR_SDADEL | \
175 					 I2C_TIMINGR_SCLDEL | I2C_TIMINGR_PRESC)
176 
177 /*
178  * I2C transfer modes
179  * I2C_RELOAD: Enable Reload mode
180  * I2C_AUTOEND_MODE: Enable automatic end mode
181  * I2C_SOFTEND_MODE: Enable software end mode
182  */
183 #define I2C_RELOAD_MODE				I2C_CR2_RELOAD
184 #define I2C_AUTOEND_MODE			I2C_CR2_AUTOEND
185 #define I2C_SOFTEND_MODE			0x0
186 
187 /*
188  * Start/restart/stop I2C transfer requests.
189  *
190  * I2C_NO_STARTSTOP: Don't Generate stop and start condition
191  * I2C_GENERATE_STOP: Generate stop condition (size should be set to 0)
192  * I2C_GENERATE_START_READ: Generate Restart for read request.
193  * I2C_GENERATE_START_WRITE: Generate Restart for write request
194  */
195 #define I2C_NO_STARTSTOP			0x0
196 #define I2C_GENERATE_STOP			(BIT(31) | I2C_CR2_STOP)
197 #define I2C_GENERATE_START_READ			(BIT(31) | I2C_CR2_START | \
198 						 I2C_CR2_RD_WRN)
199 #define I2C_GENERATE_START_WRITE		(BIT(31) | I2C_CR2_START)
200 
201 /* Memory address byte sizes */
202 #define I2C_MEMADD_SIZE_8BIT		1
203 #define I2C_MEMADD_SIZE_16BIT		2
204 
205 /* Effective rate cannot be lower than 80% target rate */
206 #define RATE_MIN(rate)			(((rate) * 80U) / 100U)
207 
208 /*
209  * struct i2c_spec_s - Private I2C timing specifications.
210  * @rate: I2C bus speed (Hz)
211  * @fall_max: Max fall time of both SDA and SCL signals (ns)
212  * @rise_max: Max rise time of both SDA and SCL signals (ns)
213  * @hddat_min: Min data hold time (ns)
214  * @vddat_max: Max data valid time (ns)
215  * @sudat_min: Min data setup time (ns)
216  * @l_min: Min low period of the SCL clock (ns)
217  * @h_min: Min high period of the SCL clock (ns)
218  */
219 struct i2c_spec_s {
220 	uint32_t rate;
221 	uint32_t fall_max;
222 	uint32_t rise_max;
223 	uint32_t hddat_min;
224 	uint32_t vddat_max;
225 	uint32_t sudat_min;
226 	uint32_t l_min;
227 	uint32_t h_min;
228 };
229 
230 /*
231  * struct i2c_timing_s - Private I2C output parameters.
232  * @scldel: Data setup time
233  * @sdadel: Data hold time
234  * @sclh: SCL high period (master mode)
235  * @sclh: SCL low period (master mode)
236  * @is_saved: True if relating to a configuration candidate
237  */
238 struct i2c_timing_s {
239 	uint8_t scldel;
240 	uint8_t sdadel;
241 	uint8_t sclh;
242 	uint8_t scll;
243 	bool is_saved;
244 };
245 
246 /* This table must be sorted in increasing value for field @rate */
247 static const struct i2c_spec_s i2c_specs[] = {
248 	/* Standard - 100KHz */
249 	{
250 		.rate = I2C_STANDARD_RATE,
251 		.fall_max = 300,
252 		.rise_max = 1000,
253 		.hddat_min = 0,
254 		.vddat_max = 3450,
255 		.sudat_min = 250,
256 		.l_min = 4700,
257 		.h_min = 4000,
258 	},
259 	/* Fast - 400KHz */
260 	{
261 		.rate = I2C_FAST_RATE,
262 		.fall_max = 300,
263 		.rise_max = 300,
264 		.hddat_min = 0,
265 		.vddat_max = 900,
266 		.sudat_min = 100,
267 		.l_min = 1300,
268 		.h_min = 600,
269 	},
270 	/* FastPlus - 1MHz */
271 	{
272 		.rate = I2C_FAST_PLUS_RATE,
273 		.fall_max = 100,
274 		.rise_max = 120,
275 		.hddat_min = 0,
276 		.vddat_max = 450,
277 		.sudat_min = 50,
278 		.l_min = 500,
279 		.h_min = 260,
280 	},
281 };
282 
283 /*
284  * I2C request parameters
285  * @dev_addr: I2C address of the target device
286  * @mode: Communication mode, one of I2C_MODE_(MASTER|MEM)
287  * @mem_addr: Target memory cell accessed in device (memory mode)
288  * @mem_addr_size: Byte size of the memory cell address (memory mode)
289  * @timeout_ms: Timeout in millisenconds for the request
290  */
291 struct i2c_request {
292 	uint32_t dev_addr;
293 	enum i2c_mode_e mode;
294 	uint32_t mem_addr;
295 	uint32_t mem_addr_size;
296 	unsigned int timeout_ms;
297 };
298 
299 static vaddr_t get_base(struct i2c_handle_s *hi2c)
300 {
301 	return io_pa_or_va_secure(&hi2c->base, hi2c->reg_size);
302 }
303 
304 static void notif_i2c_timeout(struct i2c_handle_s *hi2c)
305 {
306 	hi2c->i2c_err |= I2C_ERROR_TIMEOUT;
307 	hi2c->i2c_state = I2C_STATE_READY;
308 }
309 
310 static const struct i2c_spec_s *get_specs(uint32_t rate)
311 {
312 	size_t i = 0;
313 
314 	for (i = 0; i < ARRAY_SIZE(i2c_specs); i++)
315 		if (rate <= i2c_specs[i].rate)
316 			return i2c_specs + i;
317 
318 	return NULL;
319 }
320 
321 static void save_cfg(struct i2c_handle_s *hi2c, struct i2c_cfg *cfg)
322 {
323 	vaddr_t base = get_base(hi2c);
324 
325 	clk_enable(hi2c->clock);
326 
327 	cfg->cr1 = io_read32(base + I2C_CR1);
328 	cfg->cr2 = io_read32(base + I2C_CR2);
329 	cfg->oar1 = io_read32(base + I2C_OAR1);
330 	cfg->oar2 = io_read32(base + I2C_OAR2);
331 	cfg->timingr = io_read32(base + I2C_TIMINGR);
332 
333 	clk_disable(hi2c->clock);
334 }
335 
336 static void restore_cfg(struct i2c_handle_s *hi2c, struct i2c_cfg *cfg)
337 {
338 	vaddr_t base = get_base(hi2c);
339 
340 	clk_enable(hi2c->clock);
341 
342 	io_clrbits32(base + I2C_CR1, I2C_CR1_PE);
343 	io_write32(base + I2C_TIMINGR, cfg->timingr & TIMINGR_CLEAR_MASK);
344 	io_write32(base + I2C_OAR1, cfg->oar1);
345 	io_write32(base + I2C_CR2, cfg->cr2);
346 	io_write32(base + I2C_OAR2, cfg->oar2);
347 	io_write32(base + I2C_CR1, cfg->cr1 & ~I2C_CR1_PE);
348 	io_setbits32(base + I2C_CR1, cfg->cr1 & I2C_CR1_PE);
349 
350 	clk_disable(hi2c->clock);
351 }
352 
353 static void __maybe_unused dump_cfg(struct i2c_cfg *cfg __maybe_unused)
354 {
355 	DMSG("CR1:  %#"PRIx32, cfg->cr1);
356 	DMSG("CR2:  %#"PRIx32, cfg->cr2);
357 	DMSG("OAR1: %#"PRIx32, cfg->oar1);
358 	DMSG("OAR2: %#"PRIx32, cfg->oar2);
359 	DMSG("TIM:  %#"PRIx32, cfg->timingr);
360 }
361 
362 static void __maybe_unused dump_i2c(struct i2c_handle_s *hi2c)
363 {
364 	vaddr_t __maybe_unused base = get_base(hi2c);
365 
366 	clk_enable(hi2c->clock);
367 
368 	DMSG("CR1:  %#"PRIx32, io_read32(base + I2C_CR1));
369 	DMSG("CR2:  %#"PRIx32, io_read32(base + I2C_CR2));
370 	DMSG("OAR1: %#"PRIx32, io_read32(base + I2C_OAR1));
371 	DMSG("OAR2: %#"PRIx32, io_read32(base + I2C_OAR2));
372 	DMSG("TIM:  %#"PRIx32, io_read32(base + I2C_TIMINGR));
373 
374 	clk_disable(hi2c->clock);
375 }
376 
377 /*
378  * Compute the I2C device timings
379  *
380  * @init: Ref to the initialization configuration structure
381  * @clock_src: I2C clock source frequency (Hz)
382  * @timing: Pointer to the final computed timing result
383  * Return 0 on success or a negative value
384  */
385 static int i2c_compute_timing(struct stm32_i2c_init_s *init,
386 			      unsigned long clock_src, uint32_t *timing)
387 {
388 	const struct i2c_spec_s *specs = NULL;
389 	uint32_t speed_freq = 0;
390 	uint32_t i2cbus = UDIV_ROUND_NEAREST(I2C_NSEC_PER_SEC, speed_freq);
391 	uint32_t i2cclk = UDIV_ROUND_NEAREST(I2C_NSEC_PER_SEC, clock_src);
392 	uint32_t p_prev = I2C_TIMINGR_PRESC_MAX;
393 	uint32_t af_delay_min = 0;
394 	uint32_t af_delay_max = 0;
395 	uint32_t dnf_delay = 0;
396 	uint32_t tsync = 0;
397 	uint32_t clk_min = 0;
398 	uint32_t clk_max = 0;
399 	int clk_error_prev = 0;
400 	uint16_t p = 0;
401 	uint16_t l = 0;
402 	uint16_t a = 0;
403 	uint16_t h = 0;
404 	unsigned int sdadel_min = 0;
405 	unsigned int sdadel_max = 0;
406 	unsigned int scldel_min = 0;
407 	unsigned int delay = 0;
408 	int s = -1;
409 	struct i2c_timing_s solutions[I2C_TIMINGR_PRESC_MAX] = { 0 };
410 
411 	specs = get_specs(init->bus_rate);
412 	if (!specs) {
413 		DMSG("I2C speed out of bound: %"PRId32"Hz", init->bus_rate);
414 		return -1;
415 	}
416 
417 	speed_freq = specs->rate;
418 	i2cbus = UDIV_ROUND_NEAREST(I2C_NSEC_PER_SEC, speed_freq);
419 	clk_error_prev = INT_MAX;
420 
421 	if (init->rise_time > specs->rise_max ||
422 	    init->fall_time > specs->fall_max) {
423 		DMSG("I2C rise{%"PRId32">%"PRId32"}/fall{%"PRId32">%"PRId32"}",
424 		     init->rise_time, specs->rise_max,
425 		     init->fall_time, specs->fall_max);
426 		return -1;
427 	}
428 
429 	if (init->digital_filter_coef > STM32_I2C_DIGITAL_FILTER_MAX) {
430 		DMSG("DNF out of bound %"PRId8"/%d",
431 		     init->digital_filter_coef, STM32_I2C_DIGITAL_FILTER_MAX);
432 		return -1;
433 	}
434 
435 	/* Analog and Digital Filters */
436 	if (init->analog_filter) {
437 		af_delay_min = STM32_I2C_ANALOG_FILTER_DELAY_MIN;
438 		af_delay_max = STM32_I2C_ANALOG_FILTER_DELAY_MAX;
439 	}
440 	dnf_delay = init->digital_filter_coef * i2cclk;
441 
442 	sdadel_min = specs->hddat_min + init->fall_time;
443 	delay = af_delay_min - ((init->digital_filter_coef + 3) * i2cclk);
444 	if (SUB_OVERFLOW(sdadel_min, delay, &sdadel_min))
445 		sdadel_min = 0;
446 
447 	sdadel_max = specs->vddat_max - init->rise_time;
448 	delay = af_delay_max - ((init->digital_filter_coef + 4) * i2cclk);
449 	if (SUB_OVERFLOW(sdadel_max, delay, &sdadel_max))
450 		sdadel_max = 0;
451 
452 	scldel_min = init->rise_time + specs->sudat_min;
453 
454 	DMSG("I2C SDADEL(min/max): %u/%u, SCLDEL(Min): %u",
455 	     sdadel_min, sdadel_max, scldel_min);
456 
457 	/* Compute possible values for PRESC, SCLDEL and SDADEL */
458 	for (p = 0; p < I2C_TIMINGR_PRESC_MAX; p++) {
459 		for (l = 0; l < I2C_TIMINGR_SCLDEL_MAX; l++) {
460 			uint32_t scldel = (l + 1) * (p + 1) * i2cclk;
461 
462 			if (scldel < scldel_min)
463 				continue;
464 
465 			for (a = 0; a < I2C_TIMINGR_SDADEL_MAX; a++) {
466 				uint32_t sdadel = (a * (p + 1) + 1) * i2cclk;
467 
468 				if ((sdadel >= sdadel_min) &&
469 				    (sdadel <= sdadel_max) &&
470 				    (p != p_prev)) {
471 					solutions[p].scldel = l;
472 					solutions[p].sdadel = a;
473 					solutions[p].is_saved = true;
474 					p_prev = p;
475 					break;
476 				}
477 			}
478 
479 			if (p_prev == p)
480 				break;
481 		}
482 	}
483 
484 	if (p_prev == I2C_TIMINGR_PRESC_MAX) {
485 		DMSG("I2C no Prescaler solution");
486 		return -1;
487 	}
488 
489 	tsync = af_delay_min + dnf_delay + (2 * i2cclk);
490 	clk_max = I2C_NSEC_PER_SEC / RATE_MIN(specs->rate);
491 	clk_min = I2C_NSEC_PER_SEC / specs->rate;
492 
493 	/*
494 	 * Among prescaler possibilities discovered above figures out SCL Low
495 	 * and High Period. Provided:
496 	 * - SCL Low Period has to be higher than Low Period of the SCL Clock
497 	 *   defined by I2C Specification. I2C Clock has to be lower than
498 	 *   (SCL Low Period - Analog/Digital filters) / 4.
499 	 * - SCL High Period has to be lower than High Period of the SCL Clock
500 	 *   defined by I2C Specification.
501 	 * - I2C Clock has to be lower than SCL High Period.
502 	 */
503 	for (p = 0; p < I2C_TIMINGR_PRESC_MAX; p++) {
504 		uint32_t prescaler = (p + 1) * i2cclk;
505 
506 		if (!solutions[p].is_saved)
507 			continue;
508 
509 		for (l = 0; l < I2C_TIMINGR_SCLL_MAX; l++) {
510 			uint32_t tscl_l = ((l + 1) * prescaler) + tsync;
511 
512 			if (tscl_l < specs->l_min ||
513 			    i2cclk >= ((tscl_l - af_delay_min - dnf_delay) / 4))
514 				continue;
515 
516 			for (h = 0; h < I2C_TIMINGR_SCLH_MAX; h++) {
517 				uint32_t tscl_h = ((h + 1) * prescaler) + tsync;
518 				uint32_t tscl = tscl_l + tscl_h +
519 						init->rise_time +
520 						init->fall_time;
521 
522 				if (tscl >= clk_min && tscl <= clk_max &&
523 				    tscl_h >= specs->h_min && i2cclk < tscl_h) {
524 					int clk_error = tscl - i2cbus;
525 
526 					if (clk_error < 0)
527 						clk_error = -clk_error;
528 
529 					if (clk_error < clk_error_prev) {
530 						clk_error_prev = clk_error;
531 						solutions[p].scll = l;
532 						solutions[p].sclh = h;
533 						s = p;
534 					}
535 				}
536 			}
537 		}
538 	}
539 
540 	if (s < 0) {
541 		DMSG("I2C no solution at all");
542 		return -1;
543 	}
544 
545 	/* Finalize timing settings */
546 	*timing = I2C_SET_TIMINGR_PRESC(s) |
547 		   I2C_SET_TIMINGR_SCLDEL(solutions[s].scldel) |
548 		   I2C_SET_TIMINGR_SDADEL(solutions[s].sdadel) |
549 		   I2C_SET_TIMINGR_SCLH(solutions[s].sclh) |
550 		   I2C_SET_TIMINGR_SCLL(solutions[s].scll);
551 
552 	DMSG("I2C TIMINGR (PRESC/SCLDEL/SDADEL): %i/%"PRIu8"/%"PRIu8,
553 	     s, solutions[s].scldel, solutions[s].sdadel);
554 	DMSG("I2C TIMINGR (SCLH/SCLL): %"PRIu8"/%"PRIu8,
555 	     solutions[s].sclh, solutions[s].scll);
556 	DMSG("I2C TIMINGR: 0x%"PRIx32, *timing);
557 
558 	return 0;
559 }
560 
561 /* i2c_specs[] must be sorted by increasing rate */
562 static bool __maybe_unused i2c_specs_is_consistent(void)
563 {
564 	size_t i = 0;
565 
566 	COMPILE_TIME_ASSERT(ARRAY_SIZE(i2c_specs));
567 
568 	for (i = 1; i < ARRAY_SIZE(i2c_specs); i++)
569 		if (i2c_specs[i - 1].rate >= i2c_specs[i].rate)
570 			return false;
571 
572 	return true;
573 }
574 
575 /*
576  * @brief  From requested rate, get the closest I2C rate without exceeding it,
577  *         within I2C specification values defined in @i2c_specs.
578  * @param  rate: The requested rate.
579  * @retval Found rate, else the lowest value supported by platform.
580  */
581 static uint32_t get_lower_rate(uint32_t rate)
582 {
583 	size_t i = 0;
584 
585 	for (i = ARRAY_SIZE(i2c_specs); i > 0; i--)
586 		if (rate > i2c_specs[i - 1].rate)
587 			return i2c_specs[i - 1].rate;
588 
589 	return i2c_specs[0].rate;
590 }
591 
592 /*
593  * Setup the I2C device timings
594  *
595  * @hi2c: I2C handle structure
596  * @init: Ref to the initialization configuration structure
597  * @timing: Output TIMINGR register configuration value
598  * @retval 0 if OK, negative value else
599  */
600 static int i2c_setup_timing(struct i2c_handle_s *hi2c,
601 			    struct stm32_i2c_init_s *init,
602 			    uint32_t *timing)
603 {
604 	int rc = 0;
605 	unsigned long clock_src = 0;
606 
607 	assert(i2c_specs_is_consistent());
608 
609 	clock_src = clk_get_rate(hi2c->clock);
610 	if (!clock_src) {
611 		DMSG("Null I2C clock rate");
612 		return -1;
613 	}
614 
615 	/*
616 	 * If the timing has already been computed, and the frequency is the
617 	 * same as when it was computed, then use the saved timing.
618 	 */
619 	if (clock_src == hi2c->saved_frequency) {
620 		*timing = hi2c->saved_timing;
621 		return 0;
622 	}
623 
624 	do {
625 		rc = i2c_compute_timing(init, clock_src, timing);
626 		if (rc) {
627 			DMSG("Failed to compute I2C timings");
628 			if (init->bus_rate > I2C_STANDARD_RATE) {
629 				init->bus_rate = get_lower_rate(init->bus_rate);
630 				IMSG("Downgrade I2C speed to %"PRIu32"Hz)",
631 				     init->bus_rate);
632 			} else {
633 				break;
634 			}
635 		}
636 	} while (rc);
637 
638 	if (rc) {
639 		DMSG("Impossible to compute I2C timings");
640 		return rc;
641 	}
642 
643 	DMSG("I2C Freq(%"PRIu32"Hz), Clk Source(%lu)",
644 	     init->bus_rate, clock_src);
645 	DMSG("I2C Rise(%"PRId32") and Fall(%"PRId32") Time",
646 	     init->rise_time, init->fall_time);
647 	DMSG("I2C Analog Filter(%s), DNF(%"PRIu8")",
648 	     init->analog_filter ? "On" : "Off", init->digital_filter_coef);
649 
650 	hi2c->saved_timing = *timing;
651 	hi2c->saved_frequency = clock_src;
652 
653 	return 0;
654 }
655 
656 /*
657  * Configure I2C Analog noise filter.
658  * @hi2c: I2C handle structure
659  * @analog_filter_on: True if enabling analog filter, false otherwise
660  */
661 static void i2c_config_analog_filter(struct i2c_handle_s *hi2c,
662 				     bool analog_filter_on)
663 {
664 	vaddr_t base = get_base(hi2c);
665 
666 	/* Disable the selected I2C peripheral */
667 	io_clrbits32(base + I2C_CR1, I2C_CR1_PE);
668 
669 	/* Reset I2Cx ANOFF bit */
670 	io_clrbits32(base + I2C_CR1, I2C_CR1_ANFOFF);
671 
672 	/* Set analog filter bit if filter is disabled */
673 	if (!analog_filter_on)
674 		io_setbits32(base + I2C_CR1, I2C_CR1_ANFOFF);
675 
676 	/* Enable the selected I2C peripheral */
677 	io_setbits32(base + I2C_CR1, I2C_CR1_PE);
678 }
679 
680 TEE_Result stm32_i2c_get_setup_from_fdt(void *fdt, int node,
681 					struct stm32_i2c_init_s *init,
682 					struct pinctrl_state **pinctrl,
683 					struct pinctrl_state **pinctrl_sleep)
684 {
685 	TEE_Result res = TEE_ERROR_GENERIC;
686 	const fdt32_t *cuint = NULL;
687 	struct dt_node_info info = { .status = 0 };
688 	int __maybe_unused count = 0;
689 
690 	/* Default STM32 specific configs caller may need to overwrite */
691 	memset(init, 0, sizeof(*init));
692 
693 	fdt_fill_device_info(fdt, &info, node);
694 	assert(info.reg != DT_INFO_INVALID_REG &&
695 	       info.reg_size != DT_INFO_INVALID_REG_SIZE);
696 
697 	init->dt_status = info.status;
698 	init->pbase = info.reg;
699 	init->reg_size = info.reg_size;
700 
701 	res = clk_dt_get_by_index(fdt, node, 0, &init->clock);
702 	if (res)
703 		return res;
704 
705 	cuint = fdt_getprop(fdt, node, "i2c-scl-rising-time-ns", NULL);
706 	if (cuint)
707 		init->rise_time = fdt32_to_cpu(*cuint);
708 	else
709 		init->rise_time = STM32_I2C_RISE_TIME_DEFAULT;
710 
711 	cuint = fdt_getprop(fdt, node, "i2c-scl-falling-time-ns", NULL);
712 	if (cuint)
713 		init->fall_time = fdt32_to_cpu(*cuint);
714 	else
715 		init->fall_time = STM32_I2C_FALL_TIME_DEFAULT;
716 
717 	cuint = fdt_getprop(fdt, node, "clock-frequency", NULL);
718 	if (cuint) {
719 		init->bus_rate = fdt32_to_cpu(*cuint);
720 
721 		if (init->bus_rate > I2C_FAST_PLUS_RATE) {
722 			DMSG("Invalid bus speed (%"PRIu32" > %i)",
723 			     init->bus_rate, I2C_FAST_PLUS_RATE);
724 			return TEE_ERROR_GENERIC;
725 		}
726 	} else {
727 		init->bus_rate = I2C_STANDARD_RATE;
728 	}
729 
730 	if (pinctrl) {
731 		res = pinctrl_get_state_by_name(fdt, node, "default", pinctrl);
732 		if (res)
733 			return res;
734 	}
735 
736 	if (pinctrl_sleep) {
737 		res = pinctrl_get_state_by_name(fdt, node, "sleep",
738 						pinctrl_sleep);
739 		if (res == TEE_ERROR_ITEM_NOT_FOUND)
740 			res = TEE_SUCCESS;
741 		if (res)
742 			return res;
743 	}
744 
745 	return TEE_SUCCESS;
746 }
747 
748 int stm32_i2c_init(struct i2c_handle_s *hi2c,
749 		   struct stm32_i2c_init_s *init_data)
750 {
751 	int rc = 0;
752 	uint32_t timing = 0;
753 	vaddr_t base = 0;
754 	uint32_t val = 0;
755 
756 	rc = i2c_setup_timing(hi2c, init_data, &timing);
757 	if (rc)
758 		return rc;
759 
760 	clk_enable(hi2c->clock);
761 
762 	base = get_base(hi2c);
763 	hi2c->i2c_state = I2C_STATE_BUSY;
764 
765 	/* Disable the selected I2C peripheral */
766 	io_clrbits32(base + I2C_CR1, I2C_CR1_PE);
767 
768 	/* Configure I2Cx: Frequency range */
769 	io_write32(base + I2C_TIMINGR, timing & TIMINGR_CLEAR_MASK);
770 
771 	/* Disable Own Address1 before set the Own Address1 configuration */
772 	io_write32(base + I2C_OAR1, 0);
773 
774 	/* Configure I2Cx: Own Address1 and ack own address1 mode */
775 	if (init_data->addr_mode_10b_not_7b)
776 		io_write32(base + I2C_OAR1,
777 			   I2C_OAR1_OA1EN | I2C_OAR1_OA1MODE |
778 			   init_data->own_address1);
779 	else
780 		io_write32(base + I2C_OAR1,
781 			   I2C_OAR1_OA1EN | init_data->own_address1);
782 
783 	/* Configure I2Cx: Addressing Master mode */
784 	io_write32(base + I2C_CR2, 0);
785 	if (init_data->addr_mode_10b_not_7b)
786 		io_setbits32(base + I2C_CR2, I2C_CR2_ADD10);
787 
788 	/*
789 	 * Enable the AUTOEND by default, and enable NACK
790 	 * (should be disabled only during Slave process).
791 	 */
792 	io_setbits32(base + I2C_CR2, I2C_CR2_AUTOEND | I2C_CR2_NACK);
793 
794 	/* Disable Own Address2 before set the Own Address2 configuration */
795 	io_write32(base + I2C_OAR2, 0);
796 
797 	/* Configure I2Cx: Dual mode and Own Address2 */
798 	if (init_data->dual_address_mode)
799 		io_write32(base + I2C_OAR2,
800 			   I2C_OAR2_OA2EN | init_data->own_address2 |
801 			   (init_data->own_address2_masks << 8));
802 
803 	/* Configure I2Cx: Generalcall and NoStretch mode */
804 	val = 0;
805 	if (init_data->general_call_mode)
806 		val |= I2C_CR1_GCEN;
807 	if (init_data->no_stretch_mode)
808 		val |= I2C_CR1_NOSTRETCH;
809 	io_write32(base + I2C_CR1, val);
810 
811 	/* Enable the selected I2C peripheral */
812 	io_setbits32(base + I2C_CR1, I2C_CR1_PE);
813 
814 	hi2c->i2c_err = I2C_ERROR_NONE;
815 	hi2c->i2c_state = I2C_STATE_READY;
816 
817 	i2c_config_analog_filter(hi2c, init_data->analog_filter);
818 
819 	if (IS_ENABLED(CFG_STM32MP13))
820 		stm32_pinctrl_set_secure_cfg(hi2c->pinctrl, true);
821 
822 	clk_disable(hi2c->clock);
823 
824 	return 0;
825 }
826 
827 /* I2C transmit (TX) data register flush sequence */
828 static void i2c_flush_txdr(struct i2c_handle_s *hi2c)
829 {
830 	vaddr_t base = get_base(hi2c);
831 
832 	/*
833 	 * If a pending TXIS flag is set,
834 	 * write a dummy data in TXDR to clear it.
835 	 */
836 	if (io_read32(base + I2C_ISR) & I2C_ISR_TXIS)
837 		io_write32(base + I2C_TXDR, 0);
838 
839 	/* Flush TX register if not empty */
840 	if ((io_read32(base + I2C_ISR) & I2C_ISR_TXE) == 0)
841 		io_setbits32(base + I2C_ISR, I2C_ISR_TXE);
842 }
843 
844 /*
845  * Wait for a single target I2C_ISR bit to reach an awaited value (0 or 1)
846  *
847  * @hi2c: I2C handle structure
848  * @bit_mask: Bit mask for the target single bit position to consider
849  * @awaited_value: Awaited value of the target bit in I2C_ISR, 0 or 1
850  * @timeout_ref: Expriation timeout reference
851  * Return 0 on success and a non-zero value on timeout
852  */
853 static int wait_isr_event(struct i2c_handle_s *hi2c, uint32_t bit_mask,
854 			  unsigned int awaited_value, uint64_t timeout_ref)
855 {
856 	vaddr_t isr = get_base(hi2c) + I2C_ISR;
857 
858 	assert(IS_POWER_OF_TWO(bit_mask) && !(awaited_value & ~1U));
859 
860 	/* May timeout while TEE thread is suspended */
861 	while (!timeout_elapsed(timeout_ref))
862 		if (!!(io_read32(isr) & bit_mask) == awaited_value)
863 			break;
864 
865 	if (!!(io_read32(isr) & bit_mask) == awaited_value)
866 		return 0;
867 
868 	notif_i2c_timeout(hi2c);
869 	return -1;
870 }
871 
872 /* Handle Acknowledge-Failed sequence detection during an I2C Communication */
873 static int i2c_ack_failed(struct i2c_handle_s *hi2c, uint64_t timeout_ref)
874 {
875 	vaddr_t base = get_base(hi2c);
876 
877 	if ((io_read32(base + I2C_ISR) & I2C_ISR_NACKF) == 0U)
878 		return 0;
879 
880 	/*
881 	 * Wait until STOP Flag is reset. Use polling method.
882 	 * AutoEnd should be initiate after AF.
883 	 * Timeout may elpased while TEE thread is suspended.
884 	 */
885 	while (!timeout_elapsed(timeout_ref))
886 		if (io_read32(base + I2C_ISR) & I2C_ISR_STOPF)
887 			break;
888 
889 	if ((io_read32(base + I2C_ISR) & I2C_ISR_STOPF) == 0) {
890 		notif_i2c_timeout(hi2c);
891 		return -1;
892 	}
893 
894 	io_write32(base + I2C_ICR, I2C_ISR_NACKF);
895 
896 	io_write32(base + I2C_ICR, I2C_ISR_STOPF);
897 
898 	i2c_flush_txdr(hi2c);
899 
900 	io_clrbits32(base + I2C_CR2, CR2_RESET_MASK);
901 
902 	hi2c->i2c_err |= I2C_ERROR_ACKF;
903 	hi2c->i2c_state = I2C_STATE_READY;
904 
905 	return -1;
906 }
907 
908 /* Wait TXIS bit is 1 in I2C_ISR register */
909 static int i2c_wait_txis(struct i2c_handle_s *hi2c, uint64_t timeout_ref)
910 {
911 	while (!timeout_elapsed(timeout_ref)) {
912 		if (io_read32(get_base(hi2c) + I2C_ISR) & I2C_ISR_TXIS)
913 			break;
914 		if (i2c_ack_failed(hi2c, timeout_ref))
915 			return -1;
916 	}
917 
918 	if (io_read32(get_base(hi2c) + I2C_ISR) & I2C_ISR_TXIS)
919 		return 0;
920 
921 	if (i2c_ack_failed(hi2c, timeout_ref))
922 		return -1;
923 
924 	notif_i2c_timeout(hi2c);
925 	return -1;
926 }
927 
928 /* Wait STOPF bit is 1 in I2C_ISR register */
929 static int i2c_wait_stop(struct i2c_handle_s *hi2c, uint64_t timeout_ref)
930 {
931 	while (!timeout_elapsed(timeout_ref)) {
932 		if (io_read32(get_base(hi2c) + I2C_ISR) & I2C_ISR_STOPF)
933 			break;
934 
935 		if (i2c_ack_failed(hi2c, timeout_ref))
936 			return -1;
937 	}
938 
939 	if (io_read32(get_base(hi2c) + I2C_ISR) & I2C_ISR_STOPF)
940 		return 0;
941 
942 	if (i2c_ack_failed(hi2c, timeout_ref))
943 		return -1;
944 
945 	notif_i2c_timeout(hi2c);
946 	return -1;
947 }
948 
949 /*
950  * Load I2C_CR2 register for a I2C transfer
951  *
952  * @hi2c: I2C handle structure
953  * @dev_addr: Slave address to be transferred
954  * @size: Number of bytes to be transferred
955  * @i2c_mode: One of I2C_{RELOAD|AUTOEND|SOFTEND}_MODE: Enable Reload mode.
956  * @startstop: One of I2C_NO_STARTSTOP, I2C_GENERATE_STOP,
957  *		I2C_GENERATE_START_{READ|WRITE}
958  */
959 static void i2c_transfer_config(struct i2c_handle_s *hi2c, uint32_t dev_addr,
960 				uint32_t size, uint32_t i2c_mode,
961 				uint32_t startstop)
962 {
963 	uint32_t clr_value = I2C_CR2_SADD | I2C_CR2_NBYTES | I2C_CR2_RELOAD |
964 			     I2C_CR2_AUTOEND | I2C_CR2_START | I2C_CR2_STOP |
965 			     (I2C_CR2_RD_WRN &
966 			      (startstop >> (31U - I2C_CR2_RD_WRN_OFFSET)));
967 	uint32_t set_value = (dev_addr & I2C_CR2_SADD) |
968 			     ((size << I2C_CR2_NBYTES_OFFSET) &
969 			      I2C_CR2_NBYTES) |
970 			     i2c_mode | startstop;
971 
972 	io_clrsetbits32(get_base(hi2c) + I2C_CR2, clr_value, set_value);
973 }
974 
975 /*
976  * Master sends target device address followed by internal memory
977  * address for a memory write request.
978  * Function returns 0 on success or a negative value.
979  */
980 static int i2c_request_mem_write(struct i2c_handle_s *hi2c,
981 				 struct i2c_request *request,
982 				 uint64_t timeout_ref)
983 {
984 	vaddr_t base = get_base(hi2c);
985 
986 	i2c_transfer_config(hi2c, request->dev_addr, request->mem_addr_size,
987 			    I2C_RELOAD_MODE, I2C_GENERATE_START_WRITE);
988 
989 	if (i2c_wait_txis(hi2c, timeout_ref))
990 		return -1;
991 
992 	if (request->mem_addr_size == I2C_MEMADD_SIZE_8BIT) {
993 		/* Send memory address */
994 		io_write8(base + I2C_TXDR, request->mem_addr & 0x00FFU);
995 	} else {
996 		/* Send MSB of memory address */
997 		io_write8(base + I2C_TXDR, (request->mem_addr & 0xFF00U) >> 8);
998 
999 		if (i2c_wait_txis(hi2c, timeout_ref))
1000 			return -1;
1001 
1002 		/* Send LSB of memory address */
1003 		io_write8(base + I2C_TXDR, request->mem_addr & 0x00FFU);
1004 	}
1005 
1006 	if (wait_isr_event(hi2c, I2C_ISR_TCR, 1, timeout_ref))
1007 		return -1;
1008 
1009 	return 0;
1010 }
1011 
1012 /*
1013  * Master sends target device address followed by internal memory
1014  * address to prepare a memory read request.
1015  * Function returns 0 on success or a negative value.
1016  */
1017 static int i2c_request_mem_read(struct i2c_handle_s *hi2c,
1018 				struct i2c_request *request,
1019 				uint64_t timeout_ref)
1020 {
1021 	vaddr_t base = get_base(hi2c);
1022 
1023 	i2c_transfer_config(hi2c, request->dev_addr, request->mem_addr_size,
1024 			    I2C_SOFTEND_MODE, I2C_GENERATE_START_WRITE);
1025 
1026 	if (i2c_wait_txis(hi2c, timeout_ref))
1027 		return -1;
1028 
1029 	if (request->mem_addr_size == I2C_MEMADD_SIZE_8BIT) {
1030 		/* Send memory address */
1031 		io_write8(base + I2C_TXDR, request->mem_addr & 0x00FFU);
1032 	} else {
1033 		/* Send MSB of memory address */
1034 		io_write8(base + I2C_TXDR, (request->mem_addr & 0xFF00U) >> 8);
1035 
1036 		if (i2c_wait_txis(hi2c, timeout_ref))
1037 			return -1;
1038 
1039 		/* Send LSB of memory address */
1040 		io_write8(base + I2C_TXDR, request->mem_addr & 0x00FFU);
1041 	}
1042 
1043 	if (wait_isr_event(hi2c, I2C_ISR_TC, 1, timeout_ref))
1044 		return -1;
1045 
1046 	return 0;
1047 }
1048 
1049 /*
1050  * Write an amount of data in blocking mode
1051  *
1052  * @hi2c: Reference to struct i2c_handle_s
1053  * @request: I2C request parameters
1054  * @p_data: Pointer to data buffer
1055  * @size: Amount of data to be sent
1056  * Return 0 on success or a negative value
1057  */
1058 static int do_write(struct i2c_handle_s *hi2c, struct i2c_request *request,
1059 		    uint8_t *p_data, uint16_t size)
1060 {
1061 	uint64_t timeout_ref = 0;
1062 	vaddr_t base = get_base(hi2c);
1063 	int rc = -1;
1064 	uint8_t *p_buff = p_data;
1065 	size_t xfer_size = 0;
1066 	size_t xfer_count = size;
1067 
1068 	if (request->mode != I2C_MODE_MASTER && request->mode != I2C_MODE_MEM)
1069 		return -1;
1070 
1071 	if (hi2c->i2c_state != I2C_STATE_READY)
1072 		return -1;
1073 
1074 	if (!p_data || !size)
1075 		return -1;
1076 
1077 	clk_enable(hi2c->clock);
1078 
1079 	timeout_ref = timeout_init_us(I2C_TIMEOUT_BUSY_MS * 1000);
1080 	if (wait_isr_event(hi2c, I2C_ISR_BUSY, 0, timeout_ref))
1081 		goto bail;
1082 
1083 	hi2c->i2c_state = I2C_STATE_BUSY_TX;
1084 	hi2c->i2c_err = I2C_ERROR_NONE;
1085 	timeout_ref = timeout_init_us(request->timeout_ms * 1000);
1086 
1087 	if (request->mode == I2C_MODE_MEM) {
1088 		/* In memory mode, send slave address and memory address */
1089 		if (i2c_request_mem_write(hi2c, request, timeout_ref))
1090 			goto bail;
1091 
1092 		if (xfer_count > MAX_NBYTE_SIZE) {
1093 			xfer_size = MAX_NBYTE_SIZE;
1094 			i2c_transfer_config(hi2c, request->dev_addr, xfer_size,
1095 					    I2C_RELOAD_MODE, I2C_NO_STARTSTOP);
1096 		} else {
1097 			xfer_size = xfer_count;
1098 			i2c_transfer_config(hi2c, request->dev_addr, xfer_size,
1099 					    I2C_AUTOEND_MODE, I2C_NO_STARTSTOP);
1100 		}
1101 	} else {
1102 		/* In master mode, send slave address */
1103 		if (xfer_count > MAX_NBYTE_SIZE) {
1104 			xfer_size = MAX_NBYTE_SIZE;
1105 			i2c_transfer_config(hi2c, request->dev_addr, xfer_size,
1106 					    I2C_RELOAD_MODE,
1107 					    I2C_GENERATE_START_WRITE);
1108 		} else {
1109 			xfer_size = xfer_count;
1110 			i2c_transfer_config(hi2c, request->dev_addr, xfer_size,
1111 					    I2C_AUTOEND_MODE,
1112 					    I2C_GENERATE_START_WRITE);
1113 		}
1114 	}
1115 
1116 	do {
1117 		if (i2c_wait_txis(hi2c, timeout_ref))
1118 			goto bail;
1119 
1120 		io_write8(base + I2C_TXDR, *p_buff);
1121 		p_buff++;
1122 		xfer_count--;
1123 		xfer_size--;
1124 
1125 		if (xfer_count && !xfer_size) {
1126 			/* Wait until TCR flag is set */
1127 			if (wait_isr_event(hi2c, I2C_ISR_TCR, 1, timeout_ref))
1128 				goto bail;
1129 
1130 			if (xfer_count > MAX_NBYTE_SIZE) {
1131 				xfer_size = MAX_NBYTE_SIZE;
1132 				i2c_transfer_config(hi2c, request->dev_addr,
1133 						    xfer_size,
1134 						    I2C_RELOAD_MODE,
1135 						    I2C_NO_STARTSTOP);
1136 			} else {
1137 				xfer_size = xfer_count;
1138 				i2c_transfer_config(hi2c, request->dev_addr,
1139 						    xfer_size,
1140 						    I2C_AUTOEND_MODE,
1141 						    I2C_NO_STARTSTOP);
1142 			}
1143 		}
1144 
1145 	} while (xfer_count > 0U);
1146 
1147 	/*
1148 	 * No need to Check TC flag, with AUTOEND mode the stop
1149 	 * is automatically generated.
1150 	 * Wait until STOPF flag is reset.
1151 	 */
1152 	if (i2c_wait_stop(hi2c, timeout_ref))
1153 		goto bail;
1154 
1155 	io_write32(base + I2C_ICR, I2C_ISR_STOPF);
1156 
1157 	io_clrbits32(base + I2C_CR2, CR2_RESET_MASK);
1158 
1159 	hi2c->i2c_state = I2C_STATE_READY;
1160 
1161 	rc = 0;
1162 
1163 bail:
1164 	clk_disable(hi2c->clock);
1165 
1166 	return rc;
1167 }
1168 
1169 int stm32_i2c_mem_write(struct i2c_handle_s *hi2c, uint32_t dev_addr,
1170 			uint32_t mem_addr, uint32_t mem_addr_size,
1171 			uint8_t *p_data, size_t size, unsigned int timeout_ms)
1172 {
1173 	struct i2c_request request = {
1174 		.dev_addr = dev_addr,
1175 		.mode = I2C_MODE_MEM,
1176 		.mem_addr = mem_addr,
1177 		.mem_addr_size = mem_addr_size,
1178 		.timeout_ms = timeout_ms,
1179 	};
1180 
1181 	return do_write(hi2c, &request, p_data, size);
1182 }
1183 
1184 int stm32_i2c_master_transmit(struct i2c_handle_s *hi2c, uint32_t dev_addr,
1185 			      uint8_t *p_data, size_t size,
1186 			      unsigned int timeout_ms)
1187 {
1188 	struct i2c_request request = {
1189 		.dev_addr = dev_addr,
1190 		.mode = I2C_MODE_MASTER,
1191 		.timeout_ms = timeout_ms,
1192 	};
1193 
1194 	return do_write(hi2c, &request, p_data, size);
1195 }
1196 
1197 int stm32_i2c_read_write_membyte(struct i2c_handle_s *hi2c, uint16_t dev_addr,
1198 				 unsigned int mem_addr, uint8_t *p_data,
1199 				 bool write)
1200 {
1201 	uint64_t timeout_ref = 0;
1202 	uintptr_t base = get_base(hi2c);
1203 	int rc = -1;
1204 	uint8_t *p_buff = p_data;
1205 	uint32_t event_mask = 0;
1206 
1207 	if (hi2c->i2c_state != I2C_STATE_READY || !p_data)
1208 		return -1;
1209 
1210 	clk_enable(hi2c->clock);
1211 
1212 	timeout_ref = timeout_init_us(I2C_TIMEOUT_BUSY_US);
1213 	if (wait_isr_event(hi2c, I2C_ISR_BUSY, 0, timeout_ref))
1214 		goto bail;
1215 
1216 	hi2c->i2c_state = write ? I2C_STATE_BUSY_TX : I2C_STATE_BUSY_RX;
1217 	hi2c->i2c_err = I2C_ERROR_NONE;
1218 
1219 	i2c_transfer_config(hi2c, dev_addr, I2C_MEMADD_SIZE_8BIT,
1220 			    write ? I2C_RELOAD_MODE : I2C_SOFTEND_MODE,
1221 			    I2C_GENERATE_START_WRITE);
1222 
1223 	timeout_ref = timeout_init_us(I2C_TIMEOUT_BUSY_US);
1224 	if (i2c_wait_txis(hi2c, timeout_ref))
1225 		goto bail;
1226 
1227 	io_write8(base + I2C_TXDR, mem_addr);
1228 
1229 	if (write)
1230 		event_mask = I2C_ISR_TCR;
1231 	else
1232 		event_mask = I2C_ISR_TC;
1233 
1234 	timeout_ref = timeout_init_us(I2C_TIMEOUT_BUSY_US);
1235 	if (wait_isr_event(hi2c, event_mask, 1, timeout_ref))
1236 		goto bail;
1237 
1238 	i2c_transfer_config(hi2c, dev_addr, I2C_MEMADD_SIZE_8BIT,
1239 			    I2C_AUTOEND_MODE,
1240 			    write ? I2C_NO_STARTSTOP : I2C_GENERATE_START_READ);
1241 
1242 	timeout_ref = timeout_init_us(I2C_TIMEOUT_BUSY_US);
1243 	if (write) {
1244 		if (i2c_wait_txis(hi2c, timeout_ref))
1245 			goto bail;
1246 
1247 		io_write8(base + I2C_TXDR, *p_buff);
1248 	} else {
1249 		if (wait_isr_event(hi2c, I2C_ISR_RXNE, 1, timeout_ref))
1250 			goto bail;
1251 
1252 		*p_buff = io_read8(base + I2C_RXDR);
1253 	}
1254 
1255 	timeout_ref = timeout_init_us(I2C_TIMEOUT_BUSY_US);
1256 	if (i2c_wait_stop(hi2c, timeout_ref))
1257 		goto bail;
1258 
1259 	io_write32(base + I2C_ICR, I2C_ISR_STOPF);
1260 	io_clrbits32(base + I2C_CR2, CR2_RESET_MASK);
1261 
1262 	hi2c->i2c_state = I2C_STATE_READY;
1263 
1264 	rc = 0;
1265 
1266 bail:
1267 	clk_disable(hi2c->clock);
1268 
1269 	return rc;
1270 }
1271 
1272 /*
1273  * Read an amount of data in blocking mode
1274  *
1275  * @hi2c: Reference to struct i2c_handle_s
1276  * @request: I2C request parameters
1277  * @p_data: Pointer to data buffer
1278  * @size: Amount of data to be sent
1279  * Return 0 on success or a negative value
1280  */
1281 static int do_read(struct i2c_handle_s *hi2c, struct i2c_request *request,
1282 		   uint8_t *p_data, uint32_t size)
1283 {
1284 	vaddr_t base = get_base(hi2c);
1285 	uint64_t timeout_ref = 0;
1286 	int rc = -1;
1287 	uint8_t *p_buff = p_data;
1288 	size_t xfer_count = size;
1289 	size_t xfer_size = 0;
1290 
1291 	if (request->mode != I2C_MODE_MASTER && request->mode != I2C_MODE_MEM)
1292 		return -1;
1293 
1294 	if (hi2c->i2c_state != I2C_STATE_READY)
1295 		return -1;
1296 
1297 	if (!p_data || !size)
1298 		return -1;
1299 
1300 	clk_enable(hi2c->clock);
1301 
1302 	timeout_ref = timeout_init_us(I2C_TIMEOUT_BUSY_MS * 1000);
1303 	if (wait_isr_event(hi2c, I2C_ISR_BUSY, 0, timeout_ref))
1304 		goto bail;
1305 
1306 	hi2c->i2c_state = I2C_STATE_BUSY_RX;
1307 	hi2c->i2c_err = I2C_ERROR_NONE;
1308 	timeout_ref = timeout_init_us(request->timeout_ms * 1000);
1309 
1310 	if (request->mode == I2C_MODE_MEM) {
1311 		/* Send memory address */
1312 		if (i2c_request_mem_read(hi2c, request, timeout_ref))
1313 			goto bail;
1314 	}
1315 
1316 	/*
1317 	 * Send slave address.
1318 	 * Set NBYTES to write and reload if xfer_count > MAX_NBYTE_SIZE
1319 	 * and generate RESTART.
1320 	 */
1321 	if (xfer_count > MAX_NBYTE_SIZE) {
1322 		xfer_size = MAX_NBYTE_SIZE;
1323 		i2c_transfer_config(hi2c, request->dev_addr, xfer_size,
1324 				    I2C_RELOAD_MODE, I2C_GENERATE_START_READ);
1325 	} else {
1326 		xfer_size = xfer_count;
1327 		i2c_transfer_config(hi2c, request->dev_addr, xfer_size,
1328 				    I2C_AUTOEND_MODE, I2C_GENERATE_START_READ);
1329 	}
1330 
1331 	do {
1332 		if (wait_isr_event(hi2c, I2C_ISR_RXNE, 1,
1333 				   timeout_init_us(I2C_TIMEOUT_RXNE_MS * 1000)))
1334 			goto bail;
1335 
1336 		*p_buff = io_read8(base + I2C_RXDR);
1337 		p_buff++;
1338 		xfer_size--;
1339 		xfer_count--;
1340 
1341 		if (xfer_count && !xfer_size) {
1342 			if (wait_isr_event(hi2c, I2C_ISR_TCR, 1, timeout_ref))
1343 				goto bail;
1344 
1345 			if (xfer_count > MAX_NBYTE_SIZE) {
1346 				xfer_size = MAX_NBYTE_SIZE;
1347 				i2c_transfer_config(hi2c, request->dev_addr,
1348 						    xfer_size,
1349 						    I2C_RELOAD_MODE,
1350 						    I2C_NO_STARTSTOP);
1351 			} else {
1352 				xfer_size = xfer_count;
1353 				i2c_transfer_config(hi2c, request->dev_addr,
1354 						    xfer_size,
1355 						    I2C_AUTOEND_MODE,
1356 						    I2C_NO_STARTSTOP);
1357 			}
1358 		}
1359 	} while (xfer_count > 0U);
1360 
1361 	/*
1362 	 * No need to Check TC flag, with AUTOEND mode the stop
1363 	 * is automatically generated.
1364 	 * Wait until STOPF flag is reset.
1365 	 */
1366 	if (i2c_wait_stop(hi2c, timeout_ref))
1367 		goto bail;
1368 
1369 	/* Clear the NACK generated at the end of the transfer */
1370 	if ((io_read32(get_base(hi2c) + I2C_ISR) & I2C_ISR_NACKF))
1371 		io_write32(get_base(hi2c) + I2C_ICR, I2C_ICR_NACKCF);
1372 
1373 	io_write32(base + I2C_ICR, I2C_ISR_STOPF);
1374 
1375 	io_clrbits32(base + I2C_CR2, CR2_RESET_MASK);
1376 
1377 	hi2c->i2c_state = I2C_STATE_READY;
1378 
1379 	rc = 0;
1380 
1381 bail:
1382 	clk_disable(hi2c->clock);
1383 
1384 	return rc;
1385 }
1386 
1387 int stm32_i2c_mem_read(struct i2c_handle_s *hi2c, uint32_t dev_addr,
1388 		       uint32_t mem_addr, uint32_t mem_addr_size,
1389 		       uint8_t *p_data, size_t size, unsigned int timeout_ms)
1390 {
1391 	struct i2c_request request = {
1392 		.dev_addr = dev_addr,
1393 		.mode = I2C_MODE_MEM,
1394 		.mem_addr = mem_addr,
1395 		.mem_addr_size = mem_addr_size,
1396 		.timeout_ms = timeout_ms,
1397 	};
1398 
1399 	return do_read(hi2c, &request, p_data, size);
1400 }
1401 
1402 int stm32_i2c_master_receive(struct i2c_handle_s *hi2c, uint32_t dev_addr,
1403 			     uint8_t *p_data, size_t size,
1404 			     unsigned int timeout_ms)
1405 {
1406 	struct i2c_request request = {
1407 		.dev_addr = dev_addr,
1408 		.mode = I2C_MODE_MASTER,
1409 		.timeout_ms = timeout_ms,
1410 	};
1411 
1412 	return do_read(hi2c, &request, p_data, size);
1413 }
1414 
1415 static struct i2c_handle_s *stm32_i2c_dev_to_handle(struct i2c_dev *i2c_dev)
1416 {
1417 	struct stm32_i2c_dev *dev = container_of(i2c_dev, struct stm32_i2c_dev,
1418 						 i2c_dev);
1419 
1420 	return dev->handle;
1421 }
1422 
1423 static TEE_Result stm32_i2c_read_data(struct i2c_dev *i2c_dev, uint8_t *buf,
1424 				      size_t len)
1425 {
1426 	struct i2c_handle_s *i2c_handle = stm32_i2c_dev_to_handle(i2c_dev);
1427 	int rc = 0;
1428 
1429 	rc = stm32_i2c_master_receive(i2c_handle, i2c_dev->addr, buf, len,
1430 				      I2C_TIMEOUT_DEFAULT_MS);
1431 	if (!rc)
1432 		return TEE_SUCCESS;
1433 	else
1434 		return TEE_ERROR_GENERIC;
1435 }
1436 
1437 static TEE_Result stm32_i2c_write_data(struct i2c_dev *i2c_dev,
1438 				       const uint8_t *buf, size_t len)
1439 {
1440 	struct i2c_handle_s *i2c_handle = stm32_i2c_dev_to_handle(i2c_dev);
1441 	uint8_t *buf2 = (uint8_t *)buf;
1442 	int rc = 0;
1443 
1444 	rc = stm32_i2c_master_transmit(i2c_handle, i2c_dev->addr, buf2, len,
1445 				       I2C_TIMEOUT_DEFAULT_MS);
1446 	if (!rc)
1447 		return TEE_SUCCESS;
1448 	else
1449 		return TEE_ERROR_GENERIC;
1450 }
1451 
1452 static const struct i2c_ctrl_ops stm32_i2c_ops = {
1453 	.read = stm32_i2c_read_data,
1454 	.write = stm32_i2c_write_data,
1455 };
1456 
1457 bool stm32_i2c_is_device_ready(struct i2c_handle_s *hi2c, uint32_t dev_addr,
1458 			       unsigned int trials, unsigned int timeout_ms)
1459 {
1460 	vaddr_t base = get_base(hi2c);
1461 	unsigned int i2c_trials = 0U;
1462 	bool rc = false;
1463 
1464 	if (hi2c->i2c_state != I2C_STATE_READY)
1465 		return rc;
1466 
1467 	clk_enable(hi2c->clock);
1468 
1469 	if (io_read32(base + I2C_ISR) & I2C_ISR_BUSY)
1470 		goto bail;
1471 
1472 	hi2c->i2c_state = I2C_STATE_BUSY;
1473 	hi2c->i2c_err = I2C_ERROR_NONE;
1474 
1475 	do {
1476 		uint64_t timeout_ref = 0;
1477 		vaddr_t isr = base + I2C_ISR;
1478 
1479 		/* Generate Start */
1480 		if ((io_read32(base + I2C_OAR1) & I2C_OAR1_OA1MODE) == 0)
1481 			io_write32(base + I2C_CR2,
1482 				   ((dev_addr & I2C_CR2_SADD) |
1483 				    I2C_CR2_START | I2C_CR2_AUTOEND) &
1484 				   ~I2C_CR2_RD_WRN);
1485 		else
1486 			io_write32(base + I2C_CR2,
1487 				   ((dev_addr & I2C_CR2_SADD) |
1488 				    I2C_CR2_START | I2C_CR2_ADD10) &
1489 				   ~I2C_CR2_RD_WRN);
1490 
1491 		/*
1492 		 * No need to Check TC flag, with AUTOEND mode the stop
1493 		 * is automatically generated.
1494 		 * Wait until STOPF flag is set or a NACK flag is set.
1495 		 */
1496 		timeout_ref = timeout_init_us(timeout_ms * 1000);
1497 		while (!timeout_elapsed(timeout_ref))
1498 			if (io_read32(isr) & (I2C_ISR_STOPF | I2C_ISR_NACKF))
1499 				break;
1500 
1501 		if ((io_read32(isr) & (I2C_ISR_STOPF | I2C_ISR_NACKF)) == 0) {
1502 			notif_i2c_timeout(hi2c);
1503 			goto bail;
1504 		}
1505 
1506 		if ((io_read32(base + I2C_ISR) & I2C_ISR_NACKF) == 0U) {
1507 			if (wait_isr_event(hi2c, I2C_ISR_STOPF, 1, timeout_ref))
1508 				goto bail;
1509 
1510 			io_write32(base + I2C_ICR, I2C_ISR_STOPF);
1511 
1512 			hi2c->i2c_state = I2C_STATE_READY;
1513 
1514 			rc = true;
1515 			goto bail;
1516 		}
1517 
1518 		if (wait_isr_event(hi2c, I2C_ISR_STOPF, 1, timeout_ref))
1519 			goto bail;
1520 
1521 		io_write32(base + I2C_ICR, I2C_ISR_NACKF);
1522 		io_write32(base + I2C_ICR, I2C_ISR_STOPF);
1523 
1524 		if (i2c_trials == trials) {
1525 			io_setbits32(base + I2C_CR2, I2C_CR2_STOP);
1526 
1527 			if (wait_isr_event(hi2c, I2C_ISR_STOPF, 1, timeout_ref))
1528 				goto bail;
1529 
1530 			io_write32(base + I2C_ICR, I2C_ISR_STOPF);
1531 		}
1532 
1533 		i2c_trials++;
1534 	} while (i2c_trials < trials);
1535 
1536 	notif_i2c_timeout(hi2c);
1537 
1538 bail:
1539 	clk_disable(hi2c->clock);
1540 
1541 	return rc;
1542 }
1543 
1544 void stm32_i2c_resume(struct i2c_handle_s *hi2c)
1545 {
1546 	if (hi2c->i2c_state == I2C_STATE_READY)
1547 		return;
1548 
1549 	if ((hi2c->i2c_state != I2C_STATE_RESET) &&
1550 	    (hi2c->i2c_state != I2C_STATE_SUSPENDED))
1551 		panic();
1552 
1553 	if (pinctrl_apply_state(hi2c->pinctrl))
1554 		panic();
1555 
1556 	if (hi2c->i2c_state == I2C_STATE_RESET) {
1557 		/* There is no valid I2C configuration to be loaded yet */
1558 		return;
1559 	}
1560 
1561 	restore_cfg(hi2c, &hi2c->sec_cfg);
1562 
1563 	if (IS_ENABLED(CFG_STM32MP13))
1564 		stm32_pinctrl_set_secure_cfg(hi2c->pinctrl, true);
1565 
1566 	hi2c->i2c_state = I2C_STATE_READY;
1567 }
1568 
1569 void stm32_i2c_suspend(struct i2c_handle_s *hi2c)
1570 {
1571 	if (hi2c->i2c_state == I2C_STATE_SUSPENDED)
1572 		return;
1573 
1574 	if (hi2c->i2c_state != I2C_STATE_READY)
1575 		panic();
1576 
1577 	save_cfg(hi2c, &hi2c->sec_cfg);
1578 
1579 	if (hi2c->pinctrl_sleep && pinctrl_apply_state(hi2c->pinctrl_sleep))
1580 		panic();
1581 
1582 	hi2c->i2c_state = I2C_STATE_SUSPENDED;
1583 }
1584 
1585 static TEE_Result stm32_get_i2c_dev(struct dt_pargs *args, void *data,
1586 				    struct i2c_dev **out_device)
1587 {
1588 	struct stm32_i2c_dev *stm32_i2c_dev = NULL;
1589 	paddr_t addr = 0;
1590 
1591 	addr = fdt_reg_base_address(args->fdt, args->phandle_node);
1592 	if (addr == DT_INFO_INVALID_REG) {
1593 		DMSG("Can't get device I2C address");
1594 		return TEE_ERROR_GENERIC;
1595 	}
1596 
1597 	stm32_i2c_dev = calloc(1, sizeof(*stm32_i2c_dev));
1598 	if (!stm32_i2c_dev)
1599 		return TEE_ERROR_OUT_OF_MEMORY;
1600 
1601 	stm32_i2c_dev->handle = data;
1602 	stm32_i2c_dev->i2c_dev.addr = addr;
1603 	stm32_i2c_dev->i2c_ctrl.ops = &stm32_i2c_ops;
1604 	stm32_i2c_dev->i2c_dev.ctrl = &stm32_i2c_dev->i2c_ctrl;
1605 
1606 	*out_device = &stm32_i2c_dev->i2c_dev;
1607 
1608 	return TEE_SUCCESS;
1609 }
1610 
1611 static TEE_Result stm32_i2c_probe(const void *fdt, int node,
1612 				  const void *compat_data __unused)
1613 {
1614 	TEE_Result res = TEE_SUCCESS;
1615 	int subnode = 0;
1616 	struct i2c_handle_s *i2c_handle_p = NULL;
1617 	struct stm32_i2c_init_s init_data = { };
1618 	struct pinctrl_state *pinctrl_active = NULL;
1619 	struct pinctrl_state *pinctrl_idle = NULL;
1620 
1621 	res = stm32_i2c_get_setup_from_fdt((void *)fdt, node, &init_data,
1622 					   &pinctrl_active, &pinctrl_idle);
1623 	if (res)
1624 		return res;
1625 
1626 	i2c_handle_p = calloc(1, sizeof(struct i2c_handle_s));
1627 	if (!i2c_handle_p)
1628 		return TEE_ERROR_OUT_OF_MEMORY;
1629 
1630 	i2c_handle_p->dt_status = init_data.dt_status;
1631 	i2c_handle_p->reg_size = init_data.reg_size;
1632 	i2c_handle_p->clock = init_data.clock;
1633 	i2c_handle_p->base.pa = init_data.pbase;
1634 	i2c_handle_p->base.va = io_pa_or_va(&i2c_handle_p->base,
1635 					    init_data.reg_size);
1636 	assert(i2c_handle_p->base.va);
1637 	i2c_handle_p->clock = init_data.clock;
1638 	i2c_handle_p->i2c_state = I2C_STATE_RESET;
1639 	i2c_handle_p->pinctrl = pinctrl_active;
1640 	i2c_handle_p->pinctrl_sleep = pinctrl_idle;
1641 
1642 	init_data.analog_filter = true;
1643 	init_data.digital_filter_coef = 0;
1644 
1645 	res = stm32_i2c_init(i2c_handle_p, &init_data);
1646 	if (res)
1647 		panic("Couldn't initialise I2C");
1648 
1649 	res = i2c_register_provider(fdt, node, stm32_get_i2c_dev, i2c_handle_p);
1650 	if (res)
1651 		panic("Couldn't register I2C provider");
1652 
1653 	fdt_for_each_subnode(subnode, fdt, node) {
1654 		res = dt_driver_maybe_add_probe_node(fdt, subnode);
1655 		if (res) {
1656 			EMSG("Failed on node %s with %#"PRIx32,
1657 			     fdt_get_name(fdt, subnode, NULL), res);
1658 			panic();
1659 		}
1660 	}
1661 
1662 	return res;
1663 }
1664 
1665 static const struct dt_device_match stm32_i2c_match_table[] = {
1666 	{ .compatible = "st,stm32mp15-i2c" },
1667 	{ .compatible = "st,stm32mp13-i2c" },
1668 	{ .compatible = "st,stm32mp15-i2c-non-secure" },
1669 	{ }
1670 };
1671 
1672 DEFINE_DT_DRIVER(stm32_i2c_dt_driver) = {
1673 	.name = "stm32_i2c",
1674 	.match_table = stm32_i2c_match_table,
1675 	.probe = stm32_i2c_probe,
1676 	.type = DT_DRIVER_I2C
1677 };
1678