xref: /optee_os/core/drivers/stm32_i2c.c (revision 1e3057c68b5d8a32a394d3d0324601e3b8888d16)
1 // SPDX-License-Identifier: (GPL-2.0 OR BSD-3-Clause)
2 /*
3  * Copyright (c) 2017-2024, 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 <atomic.h>
14 #include <drivers/clk.h>
15 #include <drivers/clk_dt.h>
16 #include <drivers/pinctrl.h>
17 #include <drivers/stm32_gpio.h>
18 #include <drivers/stm32_i2c.h>
19 #include <io.h>
20 #include <kernel/boot.h>
21 #include <kernel/delay.h>
22 #include <kernel/dt.h>
23 #include <kernel/dt_driver.h>
24 #include <kernel/interrupt.h>
25 #include <kernel/mutex_pm_aware.h>
26 #include <kernel/notif.h>
27 #include <kernel/panic.h>
28 #include <kernel/thread.h>
29 #include <libfdt.h>
30 #include <stdbool.h>
31 #include <stdlib.h>
32 #include <stm32_util.h>
33 #include <trace.h>
34 
35 /* STM32 I2C registers offsets */
36 #define I2C_CR1				0x00U
37 #define I2C_CR2				0x04U
38 #define I2C_OAR1			0x08U
39 #define I2C_OAR2			0x0CU
40 #define I2C_TIMINGR			0x10U
41 #define I2C_TIMEOUTR			0x14U
42 #define I2C_ISR				0x18U
43 #define I2C_ICR				0x1CU
44 #define I2C_PECR			0x20U
45 #define I2C_RXDR			0x24U
46 #define I2C_TXDR			0x28U
47 #define I2C_SIZE			0x2CU
48 
49 /* Bit definition for I2C_CR1 register */
50 #define I2C_CR1_PE			BIT(0)
51 #define I2C_CR1_TXIE			BIT(1)
52 #define I2C_CR1_RXIE			BIT(2)
53 #define I2C_CR1_ADDRIE			BIT(3)
54 #define I2C_CR1_NACKIE			BIT(4)
55 #define I2C_CR1_STOPIE			BIT(5)
56 #define I2C_CR1_TCIE			BIT(6)
57 #define I2C_CR1_ERRIE			BIT(7)
58 #define I2C_CR1_DNF			GENMASK_32(11, 8)
59 #define I2C_CR1_ANFOFF			BIT(12)
60 #define I2C_CR1_SWRST			BIT(13)
61 #define I2C_CR1_TXDMAEN			BIT(14)
62 #define I2C_CR1_RXDMAEN			BIT(15)
63 #define I2C_CR1_SBC			BIT(16)
64 #define I2C_CR1_NOSTRETCH		BIT(17)
65 #define I2C_CR1_WUPEN			BIT(18)
66 #define I2C_CR1_GCEN			BIT(19)
67 #define I2C_CR1_SMBHEN			BIT(22)
68 #define I2C_CR1_SMBDEN			BIT(21)
69 #define I2C_CR1_ALERTEN			BIT(22)
70 #define I2C_CR1_PECEN			BIT(23)
71 
72 /* Bit definition for I2C_CR2 register */
73 #define I2C_CR2_SADD			GENMASK_32(9, 0)
74 #define I2C_CR2_RD_WRN			BIT(10)
75 #define I2C_CR2_RD_WRN_OFFSET		10U
76 #define I2C_CR2_ADD10			BIT(11)
77 #define I2C_CR2_HEAD10R			BIT(12)
78 #define I2C_CR2_START			BIT(13)
79 #define I2C_CR2_STOP			BIT(14)
80 #define I2C_CR2_NACK			BIT(15)
81 #define I2C_CR2_NBYTES			GENMASK_32(23, 16)
82 #define I2C_CR2_NBYTES_OFFSET		16U
83 #define I2C_CR2_RELOAD			BIT(24)
84 #define I2C_CR2_AUTOEND			BIT(25)
85 #define I2C_CR2_PECBYTE			BIT(26)
86 
87 /* Bit definition for I2C_OAR1 register */
88 #define I2C_OAR1_OA1			GENMASK_32(9, 0)
89 #define I2C_OAR1_OA1MODE		BIT(10)
90 #define I2C_OAR1_OA1EN			BIT(15)
91 
92 /* Bit definition for I2C_OAR2 register */
93 #define I2C_OAR2_OA2			GENMASK_32(7, 1)
94 #define I2C_OAR2_OA2MSK			GENMASK_32(10, 8)
95 #define I2C_OAR2_OA2NOMASK		0
96 #define I2C_OAR2_OA2MASK01		BIT(8)
97 #define I2C_OAR2_OA2MASK02		BIT(9)
98 #define I2C_OAR2_OA2MASK03		GENMASK_32(9, 8)
99 #define I2C_OAR2_OA2MASK04		BIT(10)
100 #define I2C_OAR2_OA2MASK05		(BIT(8) | BIT(10))
101 #define I2C_OAR2_OA2MASK06		(BIT(9) | BIT(10))
102 #define I2C_OAR2_OA2MASK07		GENMASK_32(10, 8)
103 #define I2C_OAR2_OA2EN			BIT(15)
104 
105 /* Bit definition for I2C_TIMINGR register */
106 #define I2C_TIMINGR_SCLL		GENMASK_32(7, 0)
107 #define I2C_TIMINGR_SCLH		GENMASK_32(15, 8)
108 #define I2C_TIMINGR_SDADEL		GENMASK_32(19, 16)
109 #define I2C_TIMINGR_SCLDEL		GENMASK_32(23, 20)
110 #define I2C_TIMINGR_PRESC		GENMASK_32(31, 28)
111 #define I2C_TIMINGR_SCLL_MAX		(I2C_TIMINGR_SCLL + 1)
112 #define I2C_TIMINGR_SCLH_MAX		((I2C_TIMINGR_SCLH >> 8) + 1)
113 #define I2C_TIMINGR_SDADEL_MAX		((I2C_TIMINGR_SDADEL >> 16) + 1)
114 #define I2C_TIMINGR_SCLDEL_MAX		((I2C_TIMINGR_SCLDEL >> 20) + 1)
115 #define I2C_TIMINGR_PRESC_MAX		((I2C_TIMINGR_PRESC >> 28) + 1)
116 #define I2C_SET_TIMINGR_SCLL(n)		((n) & \
117 					 (I2C_TIMINGR_SCLL_MAX - 1))
118 #define I2C_SET_TIMINGR_SCLH(n)		(((n) & \
119 					  (I2C_TIMINGR_SCLH_MAX - 1)) << 8)
120 #define I2C_SET_TIMINGR_SDADEL(n)	(((n) & \
121 					  (I2C_TIMINGR_SDADEL_MAX - 1)) << 16)
122 #define I2C_SET_TIMINGR_SCLDEL(n)	(((n) & \
123 					  (I2C_TIMINGR_SCLDEL_MAX - 1)) << 20)
124 #define I2C_SET_TIMINGR_PRESC(n)	(((n) & \
125 					  (I2C_TIMINGR_PRESC_MAX - 1)) << 28)
126 
127 /* Bit definition for I2C_TIMEOUTR register */
128 #define I2C_TIMEOUTR_TIMEOUTA		GENMASK_32(11, 0)
129 #define I2C_TIMEOUTR_TIDLE		BIT(12)
130 #define I2C_TIMEOUTR_TIMOUTEN		BIT(15)
131 #define I2C_TIMEOUTR_TIMEOUTB		GENMASK_32(27, 16)
132 #define I2C_TIMEOUTR_TEXTEN		BIT(31)
133 
134 /* Bit definition for I2C_ISR register */
135 #define I2C_ISR_TXE			BIT(0)
136 #define I2C_ISR_TXIS			BIT(1)
137 #define I2C_ISR_RXNE			BIT(2)
138 #define I2C_ISR_ADDR			BIT(3)
139 #define I2C_ISR_NACKF			BIT(4)
140 #define I2C_ISR_STOPF			BIT(5)
141 #define I2C_ISR_TC			BIT(6)
142 #define I2C_ISR_TCR			BIT(7)
143 #define I2C_ISR_BERR			BIT(8)
144 #define I2C_ISR_ARLO			BIT(9)
145 #define I2C_ISR_OVR			BIT(10)
146 #define I2C_ISR_PECERR			BIT(11)
147 #define I2C_ISR_TIMEOUT			BIT(12)
148 #define I2C_ISR_ALERT			BIT(13)
149 #define I2C_ISR_BUSY			BIT(15)
150 #define I2C_ISR_DIR			BIT(16)
151 #define I2C_ISR_ADDCODE			GENMASK_32(23, 17)
152 
153 /* Bit definition for I2C_ICR register */
154 #define I2C_ICR_ADDRCF			BIT(3)
155 #define I2C_ICR_NACKCF			BIT(4)
156 #define I2C_ICR_STOPCF			BIT(5)
157 #define I2C_ICR_BERRCF			BIT(8)
158 #define I2C_ICR_ARLOCF			BIT(9)
159 #define I2C_ICR_OVRCF			BIT(10)
160 #define I2C_ICR_PECCF			BIT(11)
161 #define I2C_ICR_TIMOUTCF		BIT(12)
162 #define I2C_ICR_ALERTCF			BIT(13)
163 
164 /* Max data size for a single I2C transfer */
165 #define MAX_NBYTE_SIZE			255U
166 
167 #define I2C_NSEC_PER_SEC		1000000000UL
168 #define I2C_TIMEOUT_BUSY_MS		25
169 #define I2C_TIMEOUT_BUSY_US		(I2C_TIMEOUT_BUSY_MS * 1000)
170 #define I2C_TIMEOUT_RXNE_MS		5
171 #define I2C_TIMEOUT_ITR_LOCKED_MS	100
172 
173 #define I2C_TIMEOUT_DEFAULT_MS		100
174 
175 #define CR2_RESET_MASK			(I2C_CR2_SADD | I2C_CR2_HEAD10R | \
176 					 I2C_CR2_NBYTES | I2C_CR2_RELOAD | \
177 					 I2C_CR2_RD_WRN)
178 
179 #define TIMINGR_CLEAR_MASK		(I2C_TIMINGR_SCLL | I2C_TIMINGR_SCLH | \
180 					 I2C_TIMINGR_SDADEL | \
181 					 I2C_TIMINGR_SCLDEL | I2C_TIMINGR_PRESC)
182 
183 /*
184  * I2C transfer modes
185  * I2C_RELOAD: Enable Reload mode
186  * I2C_AUTOEND_MODE: Enable automatic end mode
187  * I2C_SOFTEND_MODE: Enable software end mode
188  */
189 #define I2C_RELOAD_MODE				I2C_CR2_RELOAD
190 #define I2C_AUTOEND_MODE			I2C_CR2_AUTOEND
191 #define I2C_SOFTEND_MODE			0x0
192 
193 /*
194  * Start/restart/stop I2C transfer requests.
195  *
196  * I2C_NO_STARTSTOP: Don't Generate stop and start condition
197  * I2C_GENERATE_STOP: Generate stop condition (size should be set to 0)
198  * I2C_GENERATE_START_READ: Generate Restart for read request.
199  * I2C_GENERATE_START_WRITE: Generate Restart for write request
200  */
201 #define I2C_NO_STARTSTOP			0x0
202 #define I2C_GENERATE_STOP			(BIT(31) | I2C_CR2_STOP)
203 #define I2C_GENERATE_START_READ			(BIT(31) | I2C_CR2_START | \
204 						 I2C_CR2_RD_WRN)
205 #define I2C_GENERATE_START_WRITE		(BIT(31) | I2C_CR2_START)
206 
207 /* Memory address byte sizes */
208 #define I2C_MEMADD_SIZE_8BIT		1
209 #define I2C_MEMADD_SIZE_16BIT		2
210 
211 /* Effective rate cannot be lower than 80% target rate */
212 #define RATE_MIN(rate)			(((rate) * 80U) / 100U)
213 
214 /*
215  * struct i2c_spec_s - Private I2C timing specifications.
216  * @rate: I2C bus speed (Hz)
217  * @fall_max: Max fall time of both SDA and SCL signals (ns)
218  * @rise_max: Max rise time of both SDA and SCL signals (ns)
219  * @hddat_min: Min data hold time (ns)
220  * @vddat_max: Max data valid time (ns)
221  * @sudat_min: Min data setup time (ns)
222  * @l_min: Min low period of the SCL clock (ns)
223  * @h_min: Min high period of the SCL clock (ns)
224  */
225 struct i2c_spec_s {
226 	uint32_t rate;
227 	uint32_t fall_max;
228 	uint32_t rise_max;
229 	uint32_t hddat_min;
230 	uint32_t vddat_max;
231 	uint32_t sudat_min;
232 	uint32_t l_min;
233 	uint32_t h_min;
234 };
235 
236 /*
237  * struct i2c_timing_s - Private I2C output parameters.
238  * @scldel: Data setup time
239  * @sdadel: Data hold time
240  * @sclh: SCL high period (master mode)
241  * @sclh: SCL low period (master mode)
242  * @is_saved: True if relating to a configuration candidate
243  */
244 struct i2c_timing_s {
245 	uint8_t scldel;
246 	uint8_t sdadel;
247 	uint8_t sclh;
248 	uint8_t scll;
249 	bool is_saved;
250 };
251 
252 /* This table must be sorted in increasing value for field @rate */
253 static const struct i2c_spec_s i2c_specs[] = {
254 	/* Standard - 100KHz */
255 	{
256 		.rate = I2C_STANDARD_RATE,
257 		.fall_max = 300,
258 		.rise_max = 1000,
259 		.hddat_min = 0,
260 		.vddat_max = 3450,
261 		.sudat_min = 250,
262 		.l_min = 4700,
263 		.h_min = 4000,
264 	},
265 	/* Fast - 400KHz */
266 	{
267 		.rate = I2C_FAST_RATE,
268 		.fall_max = 300,
269 		.rise_max = 300,
270 		.hddat_min = 0,
271 		.vddat_max = 900,
272 		.sudat_min = 100,
273 		.l_min = 1300,
274 		.h_min = 600,
275 	},
276 	/* FastPlus - 1MHz */
277 	{
278 		.rate = I2C_FAST_PLUS_RATE,
279 		.fall_max = 100,
280 		.rise_max = 120,
281 		.hddat_min = 0,
282 		.vddat_max = 450,
283 		.sudat_min = 50,
284 		.l_min = 500,
285 		.h_min = 260,
286 	},
287 };
288 
289 /*
290  * I2C request parameters
291  * @dev_addr: I2C address of the target device
292  * @mode: Communication mode, one of I2C_MODE_(MASTER|MEM)
293  * @mem_addr: Target memory cell accessed in device (memory mode)
294  * @mem_addr_size: Byte size of the memory cell address (memory mode)
295  * @timeout_ms: Timeout in millisenconds for the request
296  */
297 struct i2c_request {
298 	uint32_t dev_addr;
299 	enum i2c_mode_e mode;
300 	uint32_t mem_addr;
301 	uint32_t mem_addr_size;
302 	unsigned int timeout_ms;
303 };
304 
305 /* Place holder for STM32MP15 non-secure I2C bus compat data */
306 static const int non_secure_bus;
307 
get_base(struct i2c_handle_s * hi2c)308 static vaddr_t get_base(struct i2c_handle_s *hi2c)
309 {
310 	return io_pa_or_va_secure(&hi2c->base, hi2c->reg_size);
311 }
312 
notif_i2c_timeout(struct i2c_handle_s * hi2c)313 static void notif_i2c_timeout(struct i2c_handle_s *hi2c)
314 {
315 	hi2c->i2c_err |= I2C_ERROR_TIMEOUT;
316 	hi2c->i2c_state = I2C_STATE_READY;
317 }
318 
get_specs(uint32_t rate)319 static const struct i2c_spec_s *get_specs(uint32_t rate)
320 {
321 	size_t i = 0;
322 
323 	for (i = 0; i < ARRAY_SIZE(i2c_specs); i++)
324 		if (rate <= i2c_specs[i].rate)
325 			return i2c_specs + i;
326 
327 	return NULL;
328 }
329 
save_cfg(struct i2c_handle_s * hi2c,struct i2c_cfg * cfg)330 static void save_cfg(struct i2c_handle_s *hi2c, struct i2c_cfg *cfg)
331 {
332 	vaddr_t base = get_base(hi2c);
333 
334 	clk_enable(hi2c->clock);
335 
336 	cfg->cr1 = io_read32(base + I2C_CR1);
337 	cfg->cr2 = io_read32(base + I2C_CR2);
338 	cfg->oar1 = io_read32(base + I2C_OAR1);
339 	cfg->oar2 = io_read32(base + I2C_OAR2);
340 	cfg->timingr = io_read32(base + I2C_TIMINGR);
341 
342 	clk_disable(hi2c->clock);
343 }
344 
restore_cfg(struct i2c_handle_s * hi2c,struct i2c_cfg * cfg)345 static void restore_cfg(struct i2c_handle_s *hi2c, struct i2c_cfg *cfg)
346 {
347 	vaddr_t base = get_base(hi2c);
348 
349 	clk_enable(hi2c->clock);
350 
351 	io_clrbits32(base + I2C_CR1, I2C_CR1_PE);
352 	io_write32(base + I2C_TIMINGR, cfg->timingr & TIMINGR_CLEAR_MASK);
353 	io_write32(base + I2C_OAR1, cfg->oar1);
354 	io_write32(base + I2C_CR2, cfg->cr2);
355 	io_write32(base + I2C_OAR2, cfg->oar2);
356 	io_write32(base + I2C_CR1, cfg->cr1 & ~I2C_CR1_PE);
357 	io_setbits32(base + I2C_CR1, cfg->cr1 & I2C_CR1_PE);
358 
359 	clk_disable(hi2c->clock);
360 }
361 
dump_cfg(struct i2c_cfg * cfg __maybe_unused)362 static void __maybe_unused dump_cfg(struct i2c_cfg *cfg __maybe_unused)
363 {
364 	DMSG("CR1:  %#"PRIx32, cfg->cr1);
365 	DMSG("CR2:  %#"PRIx32, cfg->cr2);
366 	DMSG("OAR1: %#"PRIx32, cfg->oar1);
367 	DMSG("OAR2: %#"PRIx32, cfg->oar2);
368 	DMSG("TIM:  %#"PRIx32, cfg->timingr);
369 }
370 
dump_i2c(struct i2c_handle_s * hi2c)371 static void __maybe_unused dump_i2c(struct i2c_handle_s *hi2c)
372 {
373 	vaddr_t __maybe_unused base = get_base(hi2c);
374 
375 	clk_enable(hi2c->clock);
376 
377 	DMSG("CR1:  %#"PRIx32, io_read32(base + I2C_CR1));
378 	DMSG("CR2:  %#"PRIx32, io_read32(base + I2C_CR2));
379 	DMSG("OAR1: %#"PRIx32, io_read32(base + I2C_OAR1));
380 	DMSG("OAR2: %#"PRIx32, io_read32(base + I2C_OAR2));
381 	DMSG("TIM:  %#"PRIx32, io_read32(base + I2C_TIMINGR));
382 
383 	clk_disable(hi2c->clock);
384 }
385 
386 /*
387  * Compute the I2C device timings
388  *
389  * @init: Ref to the initialization configuration structure
390  * @clock_src: I2C clock source frequency (Hz)
391  * @timing: Pointer to the final computed timing result
392  * Return 0 on success or a negative value
393  */
i2c_compute_timing(struct stm32_i2c_init_s * init,unsigned long clock_src,uint32_t * timing)394 static int i2c_compute_timing(struct stm32_i2c_init_s *init,
395 			      unsigned long clock_src, uint32_t *timing)
396 {
397 	const struct i2c_spec_s *specs = NULL;
398 	uint32_t speed_freq = 0;
399 	uint32_t i2cbus = UDIV_ROUND_NEAREST(I2C_NSEC_PER_SEC, speed_freq);
400 	uint32_t i2cclk = UDIV_ROUND_NEAREST(I2C_NSEC_PER_SEC, clock_src);
401 	uint32_t p_prev = I2C_TIMINGR_PRESC_MAX;
402 	uint32_t af_delay_min = 0;
403 	uint32_t af_delay_max = 0;
404 	uint32_t dnf_delay = 0;
405 	uint32_t tsync = 0;
406 	uint32_t clk_min = 0;
407 	uint32_t clk_max = 0;
408 	int clk_error_prev = 0;
409 	uint16_t p = 0;
410 	uint16_t l = 0;
411 	uint16_t a = 0;
412 	uint16_t h = 0;
413 	unsigned int sdadel_min = 0;
414 	unsigned int sdadel_max = 0;
415 	unsigned int scldel_min = 0;
416 	unsigned int delay = 0;
417 	int s = -1;
418 	struct i2c_timing_s solutions[I2C_TIMINGR_PRESC_MAX] = { 0 };
419 
420 	specs = get_specs(init->bus_rate);
421 	if (!specs) {
422 		DMSG("I2C speed out of bound: %"PRId32"Hz", init->bus_rate);
423 		return -1;
424 	}
425 
426 	speed_freq = specs->rate;
427 	i2cbus = UDIV_ROUND_NEAREST(I2C_NSEC_PER_SEC, speed_freq);
428 	clk_error_prev = INT_MAX;
429 
430 	if (init->rise_time > specs->rise_max ||
431 	    init->fall_time > specs->fall_max) {
432 		DMSG("I2C rise{%"PRId32">%"PRId32"}/fall{%"PRId32">%"PRId32"}",
433 		     init->rise_time, specs->rise_max,
434 		     init->fall_time, specs->fall_max);
435 		return -1;
436 	}
437 
438 	if (init->digital_filter_coef > STM32_I2C_DIGITAL_FILTER_MAX) {
439 		DMSG("DNF out of bound %"PRId8"/%d",
440 		     init->digital_filter_coef, STM32_I2C_DIGITAL_FILTER_MAX);
441 		return -1;
442 	}
443 
444 	/* Analog and Digital Filters */
445 	if (init->analog_filter) {
446 		af_delay_min = STM32_I2C_ANALOG_FILTER_DELAY_MIN;
447 		af_delay_max = STM32_I2C_ANALOG_FILTER_DELAY_MAX;
448 	}
449 	dnf_delay = init->digital_filter_coef * i2cclk;
450 
451 	sdadel_min = specs->hddat_min + init->fall_time;
452 	delay = af_delay_min - ((init->digital_filter_coef + 3) * i2cclk);
453 	if (SUB_OVERFLOW(sdadel_min, delay, &sdadel_min))
454 		sdadel_min = 0;
455 
456 	sdadel_max = specs->vddat_max - init->rise_time;
457 	delay = af_delay_max - ((init->digital_filter_coef + 4) * i2cclk);
458 	if (SUB_OVERFLOW(sdadel_max, delay, &sdadel_max))
459 		sdadel_max = 0;
460 
461 	scldel_min = init->rise_time + specs->sudat_min;
462 
463 	DMSG("I2C SDADEL(min/max): %u/%u, SCLDEL(Min): %u",
464 	     sdadel_min, sdadel_max, scldel_min);
465 
466 	/* Compute possible values for PRESC, SCLDEL and SDADEL */
467 	for (p = 0; p < I2C_TIMINGR_PRESC_MAX; p++) {
468 		for (l = 0; l < I2C_TIMINGR_SCLDEL_MAX; l++) {
469 			uint32_t scldel = (l + 1) * (p + 1) * i2cclk;
470 
471 			if (scldel < scldel_min)
472 				continue;
473 
474 			for (a = 0; a < I2C_TIMINGR_SDADEL_MAX; a++) {
475 				uint32_t sdadel = (a * (p + 1) + 1) * i2cclk;
476 
477 				if ((sdadel >= sdadel_min) &&
478 				    (sdadel <= sdadel_max) &&
479 				    (p != p_prev)) {
480 					solutions[p].scldel = l;
481 					solutions[p].sdadel = a;
482 					solutions[p].is_saved = true;
483 					p_prev = p;
484 					break;
485 				}
486 			}
487 
488 			if (p_prev == p)
489 				break;
490 		}
491 	}
492 
493 	if (p_prev == I2C_TIMINGR_PRESC_MAX) {
494 		DMSG("I2C no Prescaler solution");
495 		return -1;
496 	}
497 
498 	tsync = af_delay_min + dnf_delay + (2 * i2cclk);
499 	clk_max = I2C_NSEC_PER_SEC / RATE_MIN(specs->rate);
500 	clk_min = I2C_NSEC_PER_SEC / specs->rate;
501 
502 	/*
503 	 * Among prescaler possibilities discovered above figures out SCL Low
504 	 * and High Period. Provided:
505 	 * - SCL Low Period has to be higher than Low Period of the SCL Clock
506 	 *   defined by I2C Specification. I2C Clock has to be lower than
507 	 *   (SCL Low Period - Analog/Digital filters) / 4.
508 	 * - SCL High Period has to be lower than High Period of the SCL Clock
509 	 *   defined by I2C Specification.
510 	 * - I2C Clock has to be lower than SCL High Period.
511 	 */
512 	for (p = 0; p < I2C_TIMINGR_PRESC_MAX; p++) {
513 		uint32_t prescaler = (p + 1) * i2cclk;
514 
515 		if (!solutions[p].is_saved)
516 			continue;
517 
518 		for (l = 0; l < I2C_TIMINGR_SCLL_MAX; l++) {
519 			uint32_t tscl_l = ((l + 1) * prescaler) + tsync;
520 
521 			if (tscl_l < specs->l_min ||
522 			    i2cclk >= ((tscl_l - af_delay_min - dnf_delay) / 4))
523 				continue;
524 
525 			for (h = 0; h < I2C_TIMINGR_SCLH_MAX; h++) {
526 				uint32_t tscl_h = ((h + 1) * prescaler) + tsync;
527 				uint32_t tscl = tscl_l + tscl_h +
528 						init->rise_time +
529 						init->fall_time;
530 
531 				if (tscl >= clk_min && tscl <= clk_max &&
532 				    tscl_h >= specs->h_min && i2cclk < tscl_h) {
533 					int clk_error = tscl - i2cbus;
534 
535 					if (clk_error < 0)
536 						clk_error = -clk_error;
537 
538 					if (clk_error < clk_error_prev) {
539 						clk_error_prev = clk_error;
540 						solutions[p].scll = l;
541 						solutions[p].sclh = h;
542 						s = p;
543 					}
544 				}
545 			}
546 		}
547 	}
548 
549 	if (s < 0) {
550 		DMSG("I2C no solution at all");
551 		return -1;
552 	}
553 
554 	/* Finalize timing settings */
555 	*timing = I2C_SET_TIMINGR_PRESC(s) |
556 		   I2C_SET_TIMINGR_SCLDEL(solutions[s].scldel) |
557 		   I2C_SET_TIMINGR_SDADEL(solutions[s].sdadel) |
558 		   I2C_SET_TIMINGR_SCLH(solutions[s].sclh) |
559 		   I2C_SET_TIMINGR_SCLL(solutions[s].scll);
560 
561 	DMSG("I2C TIMINGR (PRESC/SCLDEL/SDADEL): %i/%"PRIu8"/%"PRIu8,
562 	     s, solutions[s].scldel, solutions[s].sdadel);
563 	DMSG("I2C TIMINGR (SCLH/SCLL): %"PRIu8"/%"PRIu8,
564 	     solutions[s].sclh, solutions[s].scll);
565 	DMSG("I2C TIMINGR: 0x%"PRIx32, *timing);
566 
567 	return 0;
568 }
569 
570 /* i2c_specs[] must be sorted by increasing rate */
i2c_specs_is_consistent(void)571 static bool __maybe_unused i2c_specs_is_consistent(void)
572 {
573 	size_t i = 0;
574 
575 	COMPILE_TIME_ASSERT(ARRAY_SIZE(i2c_specs));
576 
577 	for (i = 1; i < ARRAY_SIZE(i2c_specs); i++)
578 		if (i2c_specs[i - 1].rate >= i2c_specs[i].rate)
579 			return false;
580 
581 	return true;
582 }
583 
584 /*
585  * @brief  From requested rate, get the closest I2C rate without exceeding it,
586  *         within I2C specification values defined in @i2c_specs.
587  * @param  rate: The requested rate.
588  * @retval Found rate, else the lowest value supported by platform.
589  */
get_lower_rate(uint32_t rate)590 static uint32_t get_lower_rate(uint32_t rate)
591 {
592 	size_t i = 0;
593 
594 	for (i = ARRAY_SIZE(i2c_specs); i > 0; i--)
595 		if (rate > i2c_specs[i - 1].rate)
596 			return i2c_specs[i - 1].rate;
597 
598 	return i2c_specs[0].rate;
599 }
600 
601 /*
602  * Setup the I2C device timings
603  *
604  * @hi2c: I2C handle structure
605  * @init: Ref to the initialization configuration structure
606  * @timing: Output TIMINGR register configuration value
607  * @retval 0 if OK, negative value else
608  */
i2c_setup_timing(struct i2c_handle_s * hi2c,struct stm32_i2c_init_s * init,uint32_t * timing)609 static int i2c_setup_timing(struct i2c_handle_s *hi2c,
610 			    struct stm32_i2c_init_s *init,
611 			    uint32_t *timing)
612 {
613 	int rc = 0;
614 	unsigned long clock_src = 0;
615 
616 	assert(i2c_specs_is_consistent());
617 
618 	clock_src = clk_get_rate(hi2c->clock);
619 	if (!clock_src) {
620 		DMSG("Null I2C clock rate");
621 		return -1;
622 	}
623 
624 	/*
625 	 * If the timing has already been computed, and the frequency is the
626 	 * same as when it was computed, then use the saved timing.
627 	 */
628 	if (clock_src == hi2c->saved_frequency) {
629 		*timing = hi2c->saved_timing;
630 		return 0;
631 	}
632 
633 	do {
634 		rc = i2c_compute_timing(init, clock_src, timing);
635 		if (rc) {
636 			DMSG("Failed to compute I2C timings");
637 			if (init->bus_rate > I2C_STANDARD_RATE) {
638 				init->bus_rate = get_lower_rate(init->bus_rate);
639 				IMSG("Downgrade I2C speed to %"PRIu32"Hz)",
640 				     init->bus_rate);
641 			} else {
642 				break;
643 			}
644 		}
645 	} while (rc);
646 
647 	if (rc) {
648 		DMSG("Impossible to compute I2C timings");
649 		return rc;
650 	}
651 
652 	DMSG("I2C Freq(%"PRIu32"Hz), Clk Source(%lu)",
653 	     init->bus_rate, clock_src);
654 	DMSG("I2C Rise(%"PRId32") and Fall(%"PRId32") Time",
655 	     init->rise_time, init->fall_time);
656 	DMSG("I2C Analog Filter(%s), DNF(%"PRIu8")",
657 	     init->analog_filter ? "On" : "Off", init->digital_filter_coef);
658 
659 	hi2c->saved_timing = *timing;
660 	hi2c->saved_frequency = clock_src;
661 
662 	return 0;
663 }
664 
665 /*
666  * Configure I2C Analog noise filter.
667  * @hi2c: I2C handle structure
668  * @analog_filter_on: True if enabling analog filter, false otherwise
669  */
i2c_config_analog_filter(struct i2c_handle_s * hi2c,bool analog_filter_on)670 static void i2c_config_analog_filter(struct i2c_handle_s *hi2c,
671 				     bool analog_filter_on)
672 {
673 	vaddr_t base = get_base(hi2c);
674 
675 	/* Disable the selected I2C peripheral */
676 	io_clrbits32(base + I2C_CR1, I2C_CR1_PE);
677 
678 	/* Reset I2Cx ANOFF bit */
679 	io_clrbits32(base + I2C_CR1, I2C_CR1_ANFOFF);
680 
681 	/* Set analog filter bit if filter is disabled */
682 	if (!analog_filter_on)
683 		io_setbits32(base + I2C_CR1, I2C_CR1_ANFOFF);
684 
685 	/* Enable the selected I2C peripheral */
686 	io_setbits32(base + I2C_CR1, I2C_CR1_PE);
687 }
688 
stm32_i2c_get_setup_from_fdt(void * fdt,int node,struct stm32_i2c_init_s * init,struct pinctrl_state ** pinctrl,struct pinctrl_state ** pinctrl_sleep)689 TEE_Result stm32_i2c_get_setup_from_fdt(void *fdt, int node,
690 					struct stm32_i2c_init_s *init,
691 					struct pinctrl_state **pinctrl,
692 					struct pinctrl_state **pinctrl_sleep)
693 {
694 	TEE_Result res = TEE_ERROR_GENERIC;
695 	const fdt32_t *cuint = NULL;
696 	struct dt_node_info info = { .status = 0 };
697 	int __maybe_unused count = 0;
698 
699 	/* Default STM32 specific configs caller may need to overwrite */
700 	memset(init, 0, sizeof(*init));
701 
702 	fdt_fill_device_info(fdt, &info, node);
703 	assert(info.reg != DT_INFO_INVALID_REG &&
704 	       info.reg_size != DT_INFO_INVALID_REG_SIZE);
705 
706 	init->pbase = info.reg;
707 	init->reg_size = info.reg_size;
708 
709 	res = clk_dt_get_by_index(fdt, node, 0, &init->clock);
710 	if (res)
711 		return res;
712 
713 	cuint = fdt_getprop(fdt, node, "i2c-scl-rising-time-ns", NULL);
714 	if (cuint)
715 		init->rise_time = fdt32_to_cpu(*cuint);
716 	else
717 		init->rise_time = STM32_I2C_RISE_TIME_DEFAULT;
718 
719 	cuint = fdt_getprop(fdt, node, "i2c-scl-falling-time-ns", NULL);
720 	if (cuint)
721 		init->fall_time = fdt32_to_cpu(*cuint);
722 	else
723 		init->fall_time = STM32_I2C_FALL_TIME_DEFAULT;
724 
725 	cuint = fdt_getprop(fdt, node, "clock-frequency", NULL);
726 	if (cuint) {
727 		init->bus_rate = fdt32_to_cpu(*cuint);
728 
729 		if (init->bus_rate > I2C_FAST_PLUS_RATE) {
730 			DMSG("Invalid bus speed (%"PRIu32" > %i)",
731 			     init->bus_rate, I2C_FAST_PLUS_RATE);
732 			return TEE_ERROR_GENERIC;
733 		}
734 	} else {
735 		init->bus_rate = I2C_STANDARD_RATE;
736 	}
737 
738 	if (pinctrl) {
739 		res = pinctrl_get_state_by_name(fdt, node, "default", pinctrl);
740 		if (res)
741 			return res;
742 	}
743 
744 	if (pinctrl_sleep) {
745 		res = pinctrl_get_state_by_name(fdt, node, "sleep",
746 						pinctrl_sleep);
747 		if (res == TEE_ERROR_ITEM_NOT_FOUND)
748 			res = TEE_SUCCESS;
749 		if (res)
750 			return res;
751 	}
752 
753 	return TEE_SUCCESS;
754 }
755 
init_i2c_bus_access_lock(struct i2c_handle_s * hi2c)756 static void init_i2c_bus_access_lock(struct i2c_handle_s *hi2c)
757 {
758 	mutex_pm_aware_init(&hi2c->mu);
759 	hi2c->consumer_itr_lock = 0;
760 }
761 
is_thread_context(void)762 static bool is_thread_context(void)
763 {
764 	return thread_is_in_normal_mode() && thread_get_id_may_fail() >= 0;
765 }
766 
lock_i2c_bus_access(struct i2c_handle_s * hi2c)767 static void lock_i2c_bus_access(struct i2c_handle_s *hi2c)
768 {
769 	/*
770 	 * In order to support cases when a PMIC interrupt triggers
771 	 * before async notif is supported, we allow I2C access under
772 	 * interrupt context. To do so, thread context ensures PMIC
773 	 * interrupt (actually the related PWR interrupt) is masked
774 	 * while we're accessing the I2C from a thread context. We
775 	 * must also make sure any pending interrupts under execution
776 	 * complete before accessing the bus on async notif enable
777 	 * transition.
778 	 */
779 	if (is_thread_context()) {
780 		struct stm32_itr_dep *itr_dep = NULL;
781 		uint32_t exceptions = 0;
782 		uint64_t timeout = 0;
783 
784 		/* Lock thread access */
785 		mutex_pm_aware_lock(&hi2c->mu);
786 		FMSG("Thread access");
787 
788 		/*
789 		 * When async notif is not started, mask registered consumer
790 		 * interrupt during the thread context I2C access so we don't
791 		 * conflict with a interrupt access to the I2C bus. When async
792 		 * notif is started, all PMIC interrupts are routed to a thread
793 		 * execution context so we don't need to mask them.
794 		 */
795 		if (!notif_async_is_started(0)) {
796 			exceptions = thread_mask_exceptions(THREAD_EXCP_ALL);
797 
798 			hi2c->consumer_itr_masked = true;
799 
800 			/* Ensure next pending interrupts are masked */
801 			SLIST_FOREACH(itr_dep, &hi2c->consumer_itr_head, link)
802 				interrupt_mask(itr_dep->chip, itr_dep->num);
803 
804 			thread_unmask_exceptions(exceptions);
805 		}
806 
807 		/* Wait possibly executing interrupt transfer completion */
808 		timeout = timeout_init_us(I2C_TIMEOUT_ITR_LOCKED_MS * 1000);
809 		while (!timeout_elapsed(timeout))
810 			if (!atomic_load_int(&hi2c->consumer_itr_lock))
811 				break;
812 
813 		if (atomic_load_int(&hi2c->consumer_itr_lock)) {
814 			EMSG("Unexpected lengthy I2C xfer, base PA %"PRIxPA,
815 			     hi2c->base.pa);
816 			panic();
817 		}
818 	} else {
819 		FMSG("Interrupt access");
820 		atomic_store_int(&hi2c->consumer_itr_lock, 1);
821 	}
822 }
823 
unlock_i2c_bus_access(struct i2c_handle_s * hi2c)824 static void unlock_i2c_bus_access(struct i2c_handle_s *hi2c)
825 {
826 	if (is_thread_context()) {
827 		FMSG("Thread access completed");
828 
829 		if (hi2c->consumer_itr_masked) {
830 			struct stm32_itr_dep *itr_dep = NULL;
831 
832 			/* Unmask possibly pending interrupts */
833 			SLIST_FOREACH(itr_dep, &hi2c->consumer_itr_head, link)
834 				interrupt_unmask(itr_dep->chip, itr_dep->num);
835 
836 			hi2c->consumer_itr_masked = false;
837 		}
838 
839 		/* Unlock thread access */
840 		mutex_pm_aware_unlock(&hi2c->mu);
841 	} else {
842 		FMSG("Interrupt access completed");
843 		atomic_store_int(&hi2c->consumer_itr_lock, 0);
844 	}
845 }
846 
stm32_i2c_init(struct i2c_handle_s * hi2c,struct stm32_i2c_init_s * init_data)847 int stm32_i2c_init(struct i2c_handle_s *hi2c,
848 		   struct stm32_i2c_init_s *init_data)
849 {
850 	int rc = 0;
851 	uint32_t timing = 0;
852 	vaddr_t base = 0;
853 	uint32_t val = 0;
854 
855 	init_i2c_bus_access_lock(hi2c);
856 
857 	rc = i2c_setup_timing(hi2c, init_data, &timing);
858 	if (rc)
859 		return rc;
860 
861 	clk_enable(hi2c->clock);
862 
863 	base = get_base(hi2c);
864 	hi2c->i2c_state = I2C_STATE_BUSY;
865 
866 	/* Disable the selected I2C peripheral */
867 	io_clrbits32(base + I2C_CR1, I2C_CR1_PE);
868 
869 	/* Configure I2Cx: Frequency range */
870 	io_write32(base + I2C_TIMINGR, timing & TIMINGR_CLEAR_MASK);
871 
872 	/* Disable Own Address1 before set the Own Address1 configuration */
873 	io_write32(base + I2C_OAR1, 0);
874 
875 	/* Configure I2Cx: Own Address1 and ack own address1 mode */
876 	if (init_data->addr_mode_10b_not_7b)
877 		io_write32(base + I2C_OAR1,
878 			   I2C_OAR1_OA1EN | I2C_OAR1_OA1MODE |
879 			   init_data->own_address1);
880 	else
881 		io_write32(base + I2C_OAR1,
882 			   I2C_OAR1_OA1EN | init_data->own_address1);
883 
884 	/* Configure I2Cx: Addressing Master mode */
885 	io_write32(base + I2C_CR2, 0);
886 	if (init_data->addr_mode_10b_not_7b)
887 		io_setbits32(base + I2C_CR2, I2C_CR2_ADD10);
888 
889 	/*
890 	 * Enable the AUTOEND by default, and enable NACK
891 	 * (should be disabled only during Slave process).
892 	 */
893 	io_setbits32(base + I2C_CR2, I2C_CR2_AUTOEND | I2C_CR2_NACK);
894 
895 	/* Disable Own Address2 before set the Own Address2 configuration */
896 	io_write32(base + I2C_OAR2, 0);
897 
898 	/* Configure I2Cx: Dual mode and Own Address2 */
899 	if (init_data->dual_address_mode)
900 		io_write32(base + I2C_OAR2,
901 			   I2C_OAR2_OA2EN | init_data->own_address2 |
902 			   (init_data->own_address2_masks << 8));
903 
904 	/* Configure I2Cx: Generalcall and NoStretch mode */
905 	val = 0;
906 	if (init_data->general_call_mode)
907 		val |= I2C_CR1_GCEN;
908 	if (init_data->no_stretch_mode)
909 		val |= I2C_CR1_NOSTRETCH;
910 	io_write32(base + I2C_CR1, val);
911 
912 	/* Enable the selected I2C peripheral */
913 	io_setbits32(base + I2C_CR1, I2C_CR1_PE);
914 
915 	hi2c->i2c_err = I2C_ERROR_NONE;
916 	hi2c->i2c_state = I2C_STATE_READY;
917 
918 	i2c_config_analog_filter(hi2c, init_data->analog_filter);
919 
920 	clk_disable(hi2c->clock);
921 
922 	if (hi2c->pinctrl && pinctrl_apply_state(hi2c->pinctrl))
923 		return -1;
924 
925 	return 0;
926 }
927 
928 /* I2C transmit (TX) data register flush sequence */
i2c_flush_txdr(struct i2c_handle_s * hi2c)929 static void i2c_flush_txdr(struct i2c_handle_s *hi2c)
930 {
931 	vaddr_t base = get_base(hi2c);
932 
933 	/*
934 	 * If a pending TXIS flag is set,
935 	 * write a dummy data in TXDR to clear it.
936 	 */
937 	if (io_read32(base + I2C_ISR) & I2C_ISR_TXIS)
938 		io_write32(base + I2C_TXDR, 0);
939 
940 	/* Flush TX register if not empty */
941 	if ((io_read32(base + I2C_ISR) & I2C_ISR_TXE) == 0)
942 		io_setbits32(base + I2C_ISR, I2C_ISR_TXE);
943 }
944 
945 /*
946  * Wait for a single target I2C_ISR bit to reach an awaited value (0 or 1)
947  *
948  * @hi2c: I2C handle structure
949  * @bit_mask: Bit mask for the target single bit position to consider
950  * @awaited_value: Awaited value of the target bit in I2C_ISR, 0 or 1
951  * @timeout_ref: Expriation timeout reference
952  * Return 0 on success and a non-zero value on timeout
953  */
wait_isr_event(struct i2c_handle_s * hi2c,uint32_t bit_mask,unsigned int awaited_value,uint64_t timeout_ref)954 static int wait_isr_event(struct i2c_handle_s *hi2c, uint32_t bit_mask,
955 			  unsigned int awaited_value, uint64_t timeout_ref)
956 {
957 	vaddr_t isr = get_base(hi2c) + I2C_ISR;
958 
959 	assert(IS_POWER_OF_TWO(bit_mask) && !(awaited_value & ~1U));
960 
961 	/* May timeout while TEE thread is suspended */
962 	while (!timeout_elapsed(timeout_ref))
963 		if (!!(io_read32(isr) & bit_mask) == awaited_value)
964 			break;
965 
966 	if (!!(io_read32(isr) & bit_mask) == awaited_value)
967 		return 0;
968 
969 	notif_i2c_timeout(hi2c);
970 	return -1;
971 }
972 
973 /* Handle Acknowledge-Failed sequence detection during an I2C Communication */
i2c_ack_failed(struct i2c_handle_s * hi2c,uint64_t timeout_ref)974 static int i2c_ack_failed(struct i2c_handle_s *hi2c, uint64_t timeout_ref)
975 {
976 	vaddr_t base = get_base(hi2c);
977 
978 	if ((io_read32(base + I2C_ISR) & I2C_ISR_NACKF) == 0U)
979 		return 0;
980 
981 	/*
982 	 * Wait until STOP Flag is reset. Use polling method.
983 	 * AutoEnd should be initiate after AF.
984 	 * Timeout may elpased while TEE thread is suspended.
985 	 */
986 	while (!timeout_elapsed(timeout_ref))
987 		if (io_read32(base + I2C_ISR) & I2C_ISR_STOPF)
988 			break;
989 
990 	if ((io_read32(base + I2C_ISR) & I2C_ISR_STOPF) == 0) {
991 		notif_i2c_timeout(hi2c);
992 		return -1;
993 	}
994 
995 	io_write32(base + I2C_ICR, I2C_ISR_NACKF);
996 
997 	io_write32(base + I2C_ICR, I2C_ISR_STOPF);
998 
999 	i2c_flush_txdr(hi2c);
1000 
1001 	io_clrbits32(base + I2C_CR2, CR2_RESET_MASK);
1002 
1003 	hi2c->i2c_err |= I2C_ERROR_ACKF;
1004 	hi2c->i2c_state = I2C_STATE_READY;
1005 
1006 	return -1;
1007 }
1008 
1009 /* Wait TXIS bit is 1 in I2C_ISR register */
i2c_wait_txis(struct i2c_handle_s * hi2c,uint64_t timeout_ref)1010 static int i2c_wait_txis(struct i2c_handle_s *hi2c, uint64_t timeout_ref)
1011 {
1012 	while (!timeout_elapsed(timeout_ref)) {
1013 		if (io_read32(get_base(hi2c) + I2C_ISR) & I2C_ISR_TXIS)
1014 			break;
1015 		if (i2c_ack_failed(hi2c, timeout_ref))
1016 			return -1;
1017 	}
1018 
1019 	if (io_read32(get_base(hi2c) + I2C_ISR) & I2C_ISR_TXIS)
1020 		return 0;
1021 
1022 	if (i2c_ack_failed(hi2c, timeout_ref))
1023 		return -1;
1024 
1025 	notif_i2c_timeout(hi2c);
1026 	return -1;
1027 }
1028 
1029 /* Wait STOPF bit is 1 in I2C_ISR register */
i2c_wait_stop(struct i2c_handle_s * hi2c,uint64_t timeout_ref)1030 static int i2c_wait_stop(struct i2c_handle_s *hi2c, uint64_t timeout_ref)
1031 {
1032 	while (!timeout_elapsed(timeout_ref)) {
1033 		if (io_read32(get_base(hi2c) + I2C_ISR) & I2C_ISR_STOPF)
1034 			break;
1035 
1036 		if (i2c_ack_failed(hi2c, timeout_ref))
1037 			return -1;
1038 	}
1039 
1040 	if (io_read32(get_base(hi2c) + I2C_ISR) & I2C_ISR_STOPF)
1041 		return 0;
1042 
1043 	if (i2c_ack_failed(hi2c, timeout_ref))
1044 		return -1;
1045 
1046 	notif_i2c_timeout(hi2c);
1047 	return -1;
1048 }
1049 
1050 /*
1051  * Load I2C_CR2 register for a I2C transfer
1052  *
1053  * @hi2c: I2C handle structure
1054  * @dev_addr: Slave address to be transferred
1055  * @size: Number of bytes to be transferred
1056  * @i2c_mode: One of I2C_{RELOAD|AUTOEND|SOFTEND}_MODE: Enable Reload mode.
1057  * @startstop: One of I2C_NO_STARTSTOP, I2C_GENERATE_STOP,
1058  *		I2C_GENERATE_START_{READ|WRITE}
1059  */
i2c_transfer_config(struct i2c_handle_s * hi2c,uint32_t dev_addr,uint32_t size,uint32_t i2c_mode,uint32_t startstop)1060 static void i2c_transfer_config(struct i2c_handle_s *hi2c, uint32_t dev_addr,
1061 				uint32_t size, uint32_t i2c_mode,
1062 				uint32_t startstop)
1063 {
1064 	uint32_t clr_value = I2C_CR2_SADD | I2C_CR2_NBYTES | I2C_CR2_RELOAD |
1065 			     I2C_CR2_AUTOEND | I2C_CR2_START | I2C_CR2_STOP |
1066 			     (I2C_CR2_RD_WRN &
1067 			      (startstop >> (31U - I2C_CR2_RD_WRN_OFFSET)));
1068 	uint32_t set_value = (dev_addr & I2C_CR2_SADD) |
1069 			     ((size << I2C_CR2_NBYTES_OFFSET) &
1070 			      I2C_CR2_NBYTES) |
1071 			     i2c_mode | startstop;
1072 
1073 	io_clrsetbits32(get_base(hi2c) + I2C_CR2, clr_value, set_value);
1074 }
1075 
1076 /*
1077  * Master sends target device address followed by internal memory
1078  * address for a memory write request.
1079  * Function returns 0 on success or a negative value.
1080  */
i2c_request_mem_write(struct i2c_handle_s * hi2c,struct i2c_request * request,uint64_t timeout_ref)1081 static int i2c_request_mem_write(struct i2c_handle_s *hi2c,
1082 				 struct i2c_request *request,
1083 				 uint64_t timeout_ref)
1084 {
1085 	vaddr_t base = get_base(hi2c);
1086 
1087 	i2c_transfer_config(hi2c, request->dev_addr, request->mem_addr_size,
1088 			    I2C_RELOAD_MODE, I2C_GENERATE_START_WRITE);
1089 
1090 	if (i2c_wait_txis(hi2c, timeout_ref))
1091 		return -1;
1092 
1093 	if (request->mem_addr_size == I2C_MEMADD_SIZE_8BIT) {
1094 		/* Send memory address */
1095 		io_write8(base + I2C_TXDR, request->mem_addr & 0x00FFU);
1096 	} else {
1097 		/* Send MSB of memory address */
1098 		io_write8(base + I2C_TXDR, (request->mem_addr & 0xFF00U) >> 8);
1099 
1100 		if (i2c_wait_txis(hi2c, timeout_ref))
1101 			return -1;
1102 
1103 		/* Send LSB of memory address */
1104 		io_write8(base + I2C_TXDR, request->mem_addr & 0x00FFU);
1105 	}
1106 
1107 	if (wait_isr_event(hi2c, I2C_ISR_TCR, 1, timeout_ref))
1108 		return -1;
1109 
1110 	return 0;
1111 }
1112 
1113 /*
1114  * Master sends target device address followed by internal memory
1115  * address to prepare a memory read request.
1116  * Function returns 0 on success or a negative value.
1117  */
i2c_request_mem_read(struct i2c_handle_s * hi2c,struct i2c_request * request,uint64_t timeout_ref)1118 static int i2c_request_mem_read(struct i2c_handle_s *hi2c,
1119 				struct i2c_request *request,
1120 				uint64_t timeout_ref)
1121 {
1122 	vaddr_t base = get_base(hi2c);
1123 
1124 	i2c_transfer_config(hi2c, request->dev_addr, request->mem_addr_size,
1125 			    I2C_SOFTEND_MODE, I2C_GENERATE_START_WRITE);
1126 
1127 	if (i2c_wait_txis(hi2c, timeout_ref))
1128 		return -1;
1129 
1130 	if (request->mem_addr_size == I2C_MEMADD_SIZE_8BIT) {
1131 		/* Send memory address */
1132 		io_write8(base + I2C_TXDR, request->mem_addr & 0x00FFU);
1133 	} else {
1134 		/* Send MSB of memory address */
1135 		io_write8(base + I2C_TXDR, (request->mem_addr & 0xFF00U) >> 8);
1136 
1137 		if (i2c_wait_txis(hi2c, timeout_ref))
1138 			return -1;
1139 
1140 		/* Send LSB of memory address */
1141 		io_write8(base + I2C_TXDR, request->mem_addr & 0x00FFU);
1142 	}
1143 
1144 	if (wait_isr_event(hi2c, I2C_ISR_TC, 1, timeout_ref))
1145 		return -1;
1146 
1147 	return 0;
1148 }
1149 
1150 /*
1151  * Write an amount of data in blocking mode
1152  *
1153  * @hi2c: Reference to struct i2c_handle_s
1154  * @request: I2C request parameters
1155  * @p_data: Pointer to data buffer
1156  * @size: Amount of data to be sent
1157  * Return 0 on success or a negative value
1158  */
do_write(struct i2c_handle_s * hi2c,struct i2c_request * request,uint8_t * p_data,uint16_t size)1159 static int do_write(struct i2c_handle_s *hi2c, struct i2c_request *request,
1160 		    uint8_t *p_data, uint16_t size)
1161 {
1162 	uint64_t timeout_ref = 0;
1163 	vaddr_t base = get_base(hi2c);
1164 	int rc = -1;
1165 	uint8_t *p_buff = p_data;
1166 	size_t xfer_size = 0;
1167 	size_t xfer_count = size;
1168 
1169 	if (request->mode != I2C_MODE_MASTER && request->mode != I2C_MODE_MEM)
1170 		return -1;
1171 
1172 	if (!p_data || !size)
1173 		return -1;
1174 
1175 	lock_i2c_bus_access(hi2c);
1176 
1177 	if (hi2c->i2c_state != I2C_STATE_READY) {
1178 		unlock_i2c_bus_access(hi2c);
1179 		return -1;
1180 	}
1181 
1182 	clk_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_TX;
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 		/* In memory mode, send slave address and memory address */
1194 		if (i2c_request_mem_write(hi2c, request, timeout_ref))
1195 			goto bail;
1196 
1197 		if (xfer_count > MAX_NBYTE_SIZE) {
1198 			xfer_size = MAX_NBYTE_SIZE;
1199 			i2c_transfer_config(hi2c, request->dev_addr, xfer_size,
1200 					    I2C_RELOAD_MODE, I2C_NO_STARTSTOP);
1201 		} else {
1202 			xfer_size = xfer_count;
1203 			i2c_transfer_config(hi2c, request->dev_addr, xfer_size,
1204 					    I2C_AUTOEND_MODE, I2C_NO_STARTSTOP);
1205 		}
1206 	} else {
1207 		/* In master mode, send slave address */
1208 		if (xfer_count > MAX_NBYTE_SIZE) {
1209 			xfer_size = MAX_NBYTE_SIZE;
1210 			i2c_transfer_config(hi2c, request->dev_addr, xfer_size,
1211 					    I2C_RELOAD_MODE,
1212 					    I2C_GENERATE_START_WRITE);
1213 		} else {
1214 			xfer_size = xfer_count;
1215 			i2c_transfer_config(hi2c, request->dev_addr, xfer_size,
1216 					    I2C_AUTOEND_MODE,
1217 					    I2C_GENERATE_START_WRITE);
1218 		}
1219 	}
1220 
1221 	do {
1222 		if (i2c_wait_txis(hi2c, timeout_ref))
1223 			goto bail;
1224 
1225 		io_write8(base + I2C_TXDR, *p_buff);
1226 		p_buff++;
1227 		xfer_count--;
1228 		xfer_size--;
1229 
1230 		if (xfer_count && !xfer_size) {
1231 			/* Wait until TCR flag is set */
1232 			if (wait_isr_event(hi2c, I2C_ISR_TCR, 1, timeout_ref))
1233 				goto bail;
1234 
1235 			if (xfer_count > MAX_NBYTE_SIZE) {
1236 				xfer_size = MAX_NBYTE_SIZE;
1237 				i2c_transfer_config(hi2c, request->dev_addr,
1238 						    xfer_size,
1239 						    I2C_RELOAD_MODE,
1240 						    I2C_NO_STARTSTOP);
1241 			} else {
1242 				xfer_size = xfer_count;
1243 				i2c_transfer_config(hi2c, request->dev_addr,
1244 						    xfer_size,
1245 						    I2C_AUTOEND_MODE,
1246 						    I2C_NO_STARTSTOP);
1247 			}
1248 		}
1249 
1250 	} while (xfer_count > 0U);
1251 
1252 	/*
1253 	 * No need to Check TC flag, with AUTOEND mode the stop
1254 	 * is automatically generated.
1255 	 * Wait until STOPF flag is reset.
1256 	 */
1257 	if (i2c_wait_stop(hi2c, timeout_ref))
1258 		goto bail;
1259 
1260 	io_write32(base + I2C_ICR, I2C_ISR_STOPF);
1261 
1262 	io_clrbits32(base + I2C_CR2, CR2_RESET_MASK);
1263 
1264 	hi2c->i2c_state = I2C_STATE_READY;
1265 
1266 	rc = 0;
1267 
1268 bail:
1269 	clk_disable(hi2c->clock);
1270 	unlock_i2c_bus_access(hi2c);
1271 
1272 	return rc;
1273 }
1274 
stm32_i2c_mem_write(struct i2c_handle_s * hi2c,uint32_t dev_addr,uint32_t mem_addr,uint32_t mem_addr_size,uint8_t * p_data,size_t size,unsigned int timeout_ms)1275 int stm32_i2c_mem_write(struct i2c_handle_s *hi2c, uint32_t dev_addr,
1276 			uint32_t mem_addr, uint32_t mem_addr_size,
1277 			uint8_t *p_data, size_t size, unsigned int timeout_ms)
1278 {
1279 	struct i2c_request request = {
1280 		.dev_addr = dev_addr,
1281 		.mode = I2C_MODE_MEM,
1282 		.mem_addr = mem_addr,
1283 		.mem_addr_size = mem_addr_size,
1284 		.timeout_ms = timeout_ms,
1285 	};
1286 
1287 	return do_write(hi2c, &request, p_data, size);
1288 }
1289 
stm32_i2c_master_transmit(struct i2c_handle_s * hi2c,uint32_t dev_addr,uint8_t * p_data,size_t size,unsigned int timeout_ms)1290 int stm32_i2c_master_transmit(struct i2c_handle_s *hi2c, uint32_t dev_addr,
1291 			      uint8_t *p_data, size_t size,
1292 			      unsigned int timeout_ms)
1293 {
1294 	struct i2c_request request = {
1295 		.dev_addr = dev_addr,
1296 		.mode = I2C_MODE_MASTER,
1297 		.timeout_ms = timeout_ms,
1298 	};
1299 
1300 	return do_write(hi2c, &request, p_data, size);
1301 }
1302 
stm32_i2c_read_write_membyte(struct i2c_handle_s * hi2c,uint16_t dev_addr,unsigned int mem_addr,uint8_t * p_data,bool write)1303 int stm32_i2c_read_write_membyte(struct i2c_handle_s *hi2c, uint16_t dev_addr,
1304 				 unsigned int mem_addr, uint8_t *p_data,
1305 				 bool write)
1306 {
1307 	uint64_t timeout_ref = 0;
1308 	uintptr_t base = get_base(hi2c);
1309 	int rc = -1;
1310 	uint8_t *p_buff = p_data;
1311 	uint32_t event_mask = 0;
1312 
1313 	lock_i2c_bus_access(hi2c);
1314 
1315 	if (hi2c->i2c_state != I2C_STATE_READY || !p_data) {
1316 		unlock_i2c_bus_access(hi2c);
1317 		return -1;
1318 	}
1319 
1320 	clk_enable(hi2c->clock);
1321 
1322 	timeout_ref = timeout_init_us(I2C_TIMEOUT_BUSY_US);
1323 	if (wait_isr_event(hi2c, I2C_ISR_BUSY, 0, timeout_ref))
1324 		goto bail;
1325 
1326 	hi2c->i2c_state = write ? I2C_STATE_BUSY_TX : I2C_STATE_BUSY_RX;
1327 	hi2c->i2c_err = I2C_ERROR_NONE;
1328 
1329 	i2c_transfer_config(hi2c, dev_addr, I2C_MEMADD_SIZE_8BIT,
1330 			    write ? I2C_RELOAD_MODE : I2C_SOFTEND_MODE,
1331 			    I2C_GENERATE_START_WRITE);
1332 
1333 	timeout_ref = timeout_init_us(I2C_TIMEOUT_BUSY_US);
1334 	if (i2c_wait_txis(hi2c, timeout_ref))
1335 		goto bail;
1336 
1337 	io_write8(base + I2C_TXDR, mem_addr);
1338 
1339 	if (write)
1340 		event_mask = I2C_ISR_TCR;
1341 	else
1342 		event_mask = I2C_ISR_TC;
1343 
1344 	timeout_ref = timeout_init_us(I2C_TIMEOUT_BUSY_US);
1345 	if (wait_isr_event(hi2c, event_mask, 1, timeout_ref))
1346 		goto bail;
1347 
1348 	i2c_transfer_config(hi2c, dev_addr, I2C_MEMADD_SIZE_8BIT,
1349 			    I2C_AUTOEND_MODE,
1350 			    write ? I2C_NO_STARTSTOP : I2C_GENERATE_START_READ);
1351 
1352 	timeout_ref = timeout_init_us(I2C_TIMEOUT_BUSY_US);
1353 	if (write) {
1354 		if (i2c_wait_txis(hi2c, timeout_ref))
1355 			goto bail;
1356 
1357 		io_write8(base + I2C_TXDR, *p_buff);
1358 	} else {
1359 		if (wait_isr_event(hi2c, I2C_ISR_RXNE, 1, timeout_ref))
1360 			goto bail;
1361 
1362 		*p_buff = io_read8(base + I2C_RXDR);
1363 	}
1364 
1365 	timeout_ref = timeout_init_us(I2C_TIMEOUT_BUSY_US);
1366 	if (i2c_wait_stop(hi2c, timeout_ref))
1367 		goto bail;
1368 
1369 	io_write32(base + I2C_ICR, I2C_ISR_STOPF);
1370 	io_clrbits32(base + I2C_CR2, CR2_RESET_MASK);
1371 
1372 	hi2c->i2c_state = I2C_STATE_READY;
1373 
1374 	rc = 0;
1375 
1376 bail:
1377 	clk_disable(hi2c->clock);
1378 	unlock_i2c_bus_access(hi2c);
1379 
1380 	return rc;
1381 }
1382 
1383 /*
1384  * Read an amount of data in blocking mode
1385  *
1386  * @hi2c: Reference to struct i2c_handle_s
1387  * @request: I2C request parameters
1388  * @p_data: Pointer to data buffer
1389  * @size: Amount of data to be sent
1390  * Return 0 on success or a negative value
1391  */
do_read(struct i2c_handle_s * hi2c,struct i2c_request * request,uint8_t * p_data,uint32_t size)1392 static int do_read(struct i2c_handle_s *hi2c, struct i2c_request *request,
1393 		   uint8_t *p_data, uint32_t size)
1394 {
1395 	vaddr_t base = get_base(hi2c);
1396 	uint64_t timeout_ref = 0;
1397 	int rc = -1;
1398 	uint8_t *p_buff = p_data;
1399 	size_t xfer_count = size;
1400 	size_t xfer_size = 0;
1401 
1402 	if (request->mode != I2C_MODE_MASTER && request->mode != I2C_MODE_MEM)
1403 		return -1;
1404 
1405 	if (!p_data || !size)
1406 		return -1;
1407 
1408 	lock_i2c_bus_access(hi2c);
1409 
1410 	if (hi2c->i2c_state != I2C_STATE_READY) {
1411 		unlock_i2c_bus_access(hi2c);
1412 		return -1;
1413 	}
1414 
1415 	clk_enable(hi2c->clock);
1416 
1417 	timeout_ref = timeout_init_us(I2C_TIMEOUT_BUSY_MS * 1000);
1418 	if (wait_isr_event(hi2c, I2C_ISR_BUSY, 0, timeout_ref))
1419 		goto bail;
1420 
1421 	hi2c->i2c_state = I2C_STATE_BUSY_RX;
1422 	hi2c->i2c_err = I2C_ERROR_NONE;
1423 	timeout_ref = timeout_init_us(request->timeout_ms * 1000);
1424 
1425 	if (request->mode == I2C_MODE_MEM) {
1426 		/* Send memory address */
1427 		if (i2c_request_mem_read(hi2c, request, timeout_ref))
1428 			goto bail;
1429 	}
1430 
1431 	/*
1432 	 * Send slave address.
1433 	 * Set NBYTES to write and reload if xfer_count > MAX_NBYTE_SIZE
1434 	 * and generate RESTART.
1435 	 */
1436 	if (xfer_count > MAX_NBYTE_SIZE) {
1437 		xfer_size = MAX_NBYTE_SIZE;
1438 		i2c_transfer_config(hi2c, request->dev_addr, xfer_size,
1439 				    I2C_RELOAD_MODE, I2C_GENERATE_START_READ);
1440 	} else {
1441 		xfer_size = xfer_count;
1442 		i2c_transfer_config(hi2c, request->dev_addr, xfer_size,
1443 				    I2C_AUTOEND_MODE, I2C_GENERATE_START_READ);
1444 	}
1445 
1446 	do {
1447 		if (wait_isr_event(hi2c, I2C_ISR_RXNE, 1,
1448 				   timeout_init_us(I2C_TIMEOUT_RXNE_MS * 1000)))
1449 			goto bail;
1450 
1451 		*p_buff = io_read8(base + I2C_RXDR);
1452 		p_buff++;
1453 		xfer_size--;
1454 		xfer_count--;
1455 
1456 		if (xfer_count && !xfer_size) {
1457 			if (wait_isr_event(hi2c, I2C_ISR_TCR, 1, timeout_ref))
1458 				goto bail;
1459 
1460 			if (xfer_count > MAX_NBYTE_SIZE) {
1461 				xfer_size = MAX_NBYTE_SIZE;
1462 				i2c_transfer_config(hi2c, request->dev_addr,
1463 						    xfer_size,
1464 						    I2C_RELOAD_MODE,
1465 						    I2C_NO_STARTSTOP);
1466 			} else {
1467 				xfer_size = xfer_count;
1468 				i2c_transfer_config(hi2c, request->dev_addr,
1469 						    xfer_size,
1470 						    I2C_AUTOEND_MODE,
1471 						    I2C_NO_STARTSTOP);
1472 			}
1473 		}
1474 	} while (xfer_count > 0U);
1475 
1476 	/*
1477 	 * No need to Check TC flag, with AUTOEND mode the stop
1478 	 * is automatically generated.
1479 	 * Wait until STOPF flag is reset.
1480 	 */
1481 	if (i2c_wait_stop(hi2c, timeout_ref))
1482 		goto bail;
1483 
1484 	/* Clear the NACK generated at the end of the transfer */
1485 	if ((io_read32(get_base(hi2c) + I2C_ISR) & I2C_ISR_NACKF))
1486 		io_write32(get_base(hi2c) + I2C_ICR, I2C_ICR_NACKCF);
1487 
1488 	io_write32(base + I2C_ICR, I2C_ISR_STOPF);
1489 
1490 	io_clrbits32(base + I2C_CR2, CR2_RESET_MASK);
1491 
1492 	hi2c->i2c_state = I2C_STATE_READY;
1493 
1494 	rc = 0;
1495 
1496 bail:
1497 	clk_disable(hi2c->clock);
1498 	unlock_i2c_bus_access(hi2c);
1499 
1500 	return rc;
1501 }
1502 
stm32_i2c_mem_read(struct i2c_handle_s * hi2c,uint32_t dev_addr,uint32_t mem_addr,uint32_t mem_addr_size,uint8_t * p_data,size_t size,unsigned int timeout_ms)1503 int stm32_i2c_mem_read(struct i2c_handle_s *hi2c, uint32_t dev_addr,
1504 		       uint32_t mem_addr, uint32_t mem_addr_size,
1505 		       uint8_t *p_data, size_t size, unsigned int timeout_ms)
1506 {
1507 	struct i2c_request request = {
1508 		.dev_addr = dev_addr,
1509 		.mode = I2C_MODE_MEM,
1510 		.mem_addr = mem_addr,
1511 		.mem_addr_size = mem_addr_size,
1512 		.timeout_ms = timeout_ms,
1513 	};
1514 
1515 	return do_read(hi2c, &request, p_data, size);
1516 }
1517 
stm32_i2c_master_receive(struct i2c_handle_s * hi2c,uint32_t dev_addr,uint8_t * p_data,size_t size,unsigned int timeout_ms)1518 int stm32_i2c_master_receive(struct i2c_handle_s *hi2c, uint32_t dev_addr,
1519 			     uint8_t *p_data, size_t size,
1520 			     unsigned int timeout_ms)
1521 {
1522 	struct i2c_request request = {
1523 		.dev_addr = dev_addr,
1524 		.mode = I2C_MODE_MASTER,
1525 		.timeout_ms = timeout_ms,
1526 	};
1527 
1528 	return do_read(hi2c, &request, p_data, size);
1529 }
1530 
stm32_i2c_dev_to_handle(struct i2c_dev * i2c_dev)1531 static struct i2c_handle_s *stm32_i2c_dev_to_handle(struct i2c_dev *i2c_dev)
1532 {
1533 	struct stm32_i2c_dev *dev = container_of(i2c_dev, struct stm32_i2c_dev,
1534 						 i2c_dev);
1535 
1536 	return dev->handle;
1537 }
1538 
stm32_i2c_read_data(struct i2c_dev * i2c_dev,uint8_t * buf,size_t len)1539 static TEE_Result stm32_i2c_read_data(struct i2c_dev *i2c_dev, uint8_t *buf,
1540 				      size_t len)
1541 {
1542 	struct i2c_handle_s *i2c_handle = stm32_i2c_dev_to_handle(i2c_dev);
1543 	int rc = 0;
1544 
1545 	rc = stm32_i2c_master_receive(i2c_handle, i2c_dev->addr, buf, len,
1546 				      I2C_TIMEOUT_DEFAULT_MS);
1547 	if (!rc)
1548 		return TEE_SUCCESS;
1549 	else
1550 		return TEE_ERROR_GENERIC;
1551 }
1552 
stm32_i2c_write_data(struct i2c_dev * i2c_dev,const uint8_t * buf,size_t len)1553 static TEE_Result stm32_i2c_write_data(struct i2c_dev *i2c_dev,
1554 				       const uint8_t *buf, size_t len)
1555 {
1556 	struct i2c_handle_s *i2c_handle = stm32_i2c_dev_to_handle(i2c_dev);
1557 	uint8_t *buf2 = (uint8_t *)buf;
1558 	int rc = 0;
1559 
1560 	rc = stm32_i2c_master_transmit(i2c_handle, i2c_dev->addr, buf2, len,
1561 				       I2C_TIMEOUT_DEFAULT_MS);
1562 	if (!rc)
1563 		return TEE_SUCCESS;
1564 	else
1565 		return TEE_ERROR_GENERIC;
1566 }
1567 
1568 static const struct i2c_ctrl_ops stm32_i2c_ops = {
1569 	.read = stm32_i2c_read_data,
1570 	.write = stm32_i2c_write_data,
1571 };
1572 
stm32_i2c_is_device_ready(struct i2c_handle_s * hi2c,uint32_t dev_addr,unsigned int trials,unsigned int timeout_ms)1573 bool stm32_i2c_is_device_ready(struct i2c_handle_s *hi2c, uint32_t dev_addr,
1574 			       unsigned int trials, unsigned int timeout_ms)
1575 {
1576 	vaddr_t base = get_base(hi2c);
1577 	unsigned int i2c_trials = 0U;
1578 	bool rc = false;
1579 
1580 	lock_i2c_bus_access(hi2c);
1581 
1582 	if (hi2c->i2c_state != I2C_STATE_READY) {
1583 		unlock_i2c_bus_access(hi2c);
1584 		return rc;
1585 	}
1586 
1587 	clk_enable(hi2c->clock);
1588 
1589 	if (io_read32(base + I2C_ISR) & I2C_ISR_BUSY)
1590 		goto bail;
1591 
1592 	hi2c->i2c_state = I2C_STATE_BUSY;
1593 	hi2c->i2c_err = I2C_ERROR_NONE;
1594 
1595 	do {
1596 		uint64_t timeout_ref = 0;
1597 		vaddr_t isr = base + I2C_ISR;
1598 
1599 		/* Generate Start */
1600 		if ((io_read32(base + I2C_OAR1) & I2C_OAR1_OA1MODE) == 0)
1601 			io_write32(base + I2C_CR2,
1602 				   ((dev_addr & I2C_CR2_SADD) |
1603 				    I2C_CR2_START | I2C_CR2_AUTOEND) &
1604 				   ~I2C_CR2_RD_WRN);
1605 		else
1606 			io_write32(base + I2C_CR2,
1607 				   ((dev_addr & I2C_CR2_SADD) |
1608 				    I2C_CR2_START | I2C_CR2_ADD10) &
1609 				   ~I2C_CR2_RD_WRN);
1610 
1611 		/*
1612 		 * No need to Check TC flag, with AUTOEND mode the stop
1613 		 * is automatically generated.
1614 		 * Wait until STOPF flag is set or a NACK flag is set.
1615 		 */
1616 		timeout_ref = timeout_init_us(timeout_ms * 1000);
1617 		while (!timeout_elapsed(timeout_ref))
1618 			if (io_read32(isr) & (I2C_ISR_STOPF | I2C_ISR_NACKF))
1619 				break;
1620 
1621 		if ((io_read32(isr) & (I2C_ISR_STOPF | I2C_ISR_NACKF)) == 0) {
1622 			notif_i2c_timeout(hi2c);
1623 			goto bail;
1624 		}
1625 
1626 		if ((io_read32(base + I2C_ISR) & I2C_ISR_NACKF) == 0U) {
1627 			if (wait_isr_event(hi2c, I2C_ISR_STOPF, 1, timeout_ref))
1628 				goto bail;
1629 
1630 			io_write32(base + I2C_ICR, I2C_ISR_STOPF);
1631 
1632 			hi2c->i2c_state = I2C_STATE_READY;
1633 
1634 			rc = true;
1635 			goto bail;
1636 		}
1637 
1638 		if (wait_isr_event(hi2c, I2C_ISR_STOPF, 1, timeout_ref))
1639 			goto bail;
1640 
1641 		io_write32(base + I2C_ICR, I2C_ISR_NACKF);
1642 		io_write32(base + I2C_ICR, I2C_ISR_STOPF);
1643 
1644 		if (i2c_trials == trials) {
1645 			io_setbits32(base + I2C_CR2, I2C_CR2_STOP);
1646 
1647 			if (wait_isr_event(hi2c, I2C_ISR_STOPF, 1, timeout_ref))
1648 				goto bail;
1649 
1650 			io_write32(base + I2C_ICR, I2C_ISR_STOPF);
1651 		}
1652 
1653 		i2c_trials++;
1654 	} while (i2c_trials < trials);
1655 
1656 	notif_i2c_timeout(hi2c);
1657 
1658 bail:
1659 	clk_disable(hi2c->clock);
1660 	unlock_i2c_bus_access(hi2c);
1661 
1662 	return rc;
1663 }
1664 
stm32_i2c_interrupt_access_lockdeps(struct i2c_handle_s * hi2c,struct itr_chip * itr_chip,size_t itr_num)1665 void stm32_i2c_interrupt_access_lockdeps(struct i2c_handle_s *hi2c,
1666 					 struct itr_chip *itr_chip,
1667 					 size_t itr_num)
1668 {
1669 	struct stm32_itr_dep *itr_dep = NULL;
1670 
1671 	itr_dep = calloc(1, sizeof(*itr_dep));
1672 	if (!itr_dep)
1673 		panic();
1674 
1675 	itr_dep->chip = itr_chip;
1676 	itr_dep->num = itr_num;
1677 	SLIST_INSERT_HEAD(&hi2c->consumer_itr_head, itr_dep, link);
1678 }
1679 
stm32_i2c_resume(struct i2c_handle_s * hi2c)1680 void stm32_i2c_resume(struct i2c_handle_s *hi2c)
1681 {
1682 	if (hi2c->i2c_state == I2C_STATE_READY)
1683 		return;
1684 
1685 	if ((hi2c->i2c_state != I2C_STATE_RESET) &&
1686 	    (hi2c->i2c_state != I2C_STATE_SUSPENDED))
1687 		panic();
1688 
1689 	if (pinctrl_apply_state(hi2c->pinctrl))
1690 		panic();
1691 
1692 	if (hi2c->i2c_state == I2C_STATE_RESET) {
1693 		/* There is no valid I2C configuration to be loaded yet */
1694 		return;
1695 	}
1696 
1697 	restore_cfg(hi2c, &hi2c->sec_cfg);
1698 
1699 	hi2c->i2c_state = I2C_STATE_READY;
1700 }
1701 
stm32_i2c_suspend(struct i2c_handle_s * hi2c)1702 void stm32_i2c_suspend(struct i2c_handle_s *hi2c)
1703 {
1704 	if (hi2c->i2c_state == I2C_STATE_SUSPENDED)
1705 		return;
1706 
1707 	if (hi2c->i2c_state != I2C_STATE_READY)
1708 		panic();
1709 
1710 	save_cfg(hi2c, &hi2c->sec_cfg);
1711 
1712 	if (hi2c->pinctrl_sleep && pinctrl_apply_state(hi2c->pinctrl_sleep))
1713 		panic();
1714 
1715 	hi2c->i2c_state = I2C_STATE_SUSPENDED;
1716 }
1717 
stm32_get_i2c_dev(struct dt_pargs * args,void * data,struct i2c_dev ** out_device)1718 static TEE_Result stm32_get_i2c_dev(struct dt_pargs *args, void *data,
1719 				    struct i2c_dev **out_device)
1720 {
1721 	struct stm32_i2c_dev *stm32_i2c_dev = NULL;
1722 	paddr_t addr = 0;
1723 
1724 	addr = fdt_reg_base_address(args->fdt, args->consumer_node);
1725 	if (addr == DT_INFO_INVALID_REG) {
1726 		DMSG("Can't get device I2C address");
1727 		return TEE_ERROR_GENERIC;
1728 	}
1729 
1730 	stm32_i2c_dev = calloc(1, sizeof(*stm32_i2c_dev));
1731 	if (!stm32_i2c_dev)
1732 		return TEE_ERROR_OUT_OF_MEMORY;
1733 
1734 	stm32_i2c_dev->handle = data;
1735 	stm32_i2c_dev->i2c_dev.addr = addr;
1736 	stm32_i2c_dev->i2c_ctrl.ops = &stm32_i2c_ops;
1737 	stm32_i2c_dev->i2c_dev.ctrl = &stm32_i2c_dev->i2c_ctrl;
1738 
1739 	*out_device = &stm32_i2c_dev->i2c_dev;
1740 
1741 	return TEE_SUCCESS;
1742 }
1743 
stm32_i2c_probe(const void * fdt,int node,const void * compat_data)1744 static TEE_Result stm32_i2c_probe(const void *fdt, int node,
1745 				  const void *compat_data)
1746 {
1747 	TEE_Result res = TEE_SUCCESS;
1748 	int subnode = 0;
1749 	struct i2c_handle_s *i2c_handle_p = NULL;
1750 	struct stm32_i2c_init_s init_data = { };
1751 	struct pinctrl_state *pinctrl_active = NULL;
1752 	struct pinctrl_state *pinctrl_idle = NULL;
1753 
1754 	res = stm32_i2c_get_setup_from_fdt((void *)fdt, node, &init_data,
1755 					   &pinctrl_active, &pinctrl_idle);
1756 	if (res)
1757 		return res;
1758 
1759 	i2c_handle_p = calloc(1, sizeof(struct i2c_handle_s));
1760 	if (!i2c_handle_p)
1761 		return TEE_ERROR_OUT_OF_MEMORY;
1762 
1763 	i2c_handle_p->reg_size = init_data.reg_size;
1764 	i2c_handle_p->clock = init_data.clock;
1765 	i2c_handle_p->base.pa = init_data.pbase;
1766 	i2c_handle_p->base.va = io_pa_or_va(&i2c_handle_p->base,
1767 					    init_data.reg_size);
1768 	assert(i2c_handle_p->base.va);
1769 	i2c_handle_p->clock = init_data.clock;
1770 	i2c_handle_p->i2c_state = I2C_STATE_RESET;
1771 	i2c_handle_p->pinctrl = pinctrl_active;
1772 	i2c_handle_p->pinctrl_sleep = pinctrl_idle;
1773 
1774 	if (compat_data != &non_secure_bus)
1775 		i2c_handle_p->i2c_secure = true;
1776 
1777 	init_data.analog_filter = true;
1778 	init_data.digital_filter_coef = 0;
1779 
1780 	if (stm32_i2c_init(i2c_handle_p, &init_data))
1781 		panic("Couldn't initialise I2C");
1782 
1783 	res = i2c_register_provider(fdt, node, stm32_get_i2c_dev, i2c_handle_p);
1784 	if (res)
1785 		panic("Couldn't register I2C provider");
1786 
1787 	fdt_for_each_subnode(subnode, fdt, node) {
1788 		res = dt_driver_maybe_add_probe_node(fdt, subnode);
1789 		if (res) {
1790 			EMSG("Failed on node %s with %#"PRIx32,
1791 			     fdt_get_name(fdt, subnode, NULL), res);
1792 			panic();
1793 		}
1794 	}
1795 
1796 	return res;
1797 }
1798 
1799 static const struct dt_device_match stm32_i2c_match_table[] = {
1800 	{ .compatible = "st,stm32mp15-i2c" },
1801 	{ .compatible = "st,stm32mp13-i2c" },
1802 	{
1803 		.compatible = "st,stm32mp15-i2c-non-secure",
1804 		.compat_data = &non_secure_bus,
1805 	},
1806 	{ .compatible = "st,stm32mp25-i2c" },
1807 	{ }
1808 };
1809 
1810 DEFINE_DT_DRIVER(stm32_i2c_dt_driver) = {
1811 	.name = "stm32_i2c",
1812 	.match_table = stm32_i2c_match_table,
1813 	.probe = stm32_i2c_probe,
1814 	.type = DT_DRIVER_I2C
1815 };
1816