1 // SPDX-License-Identifier: GPL-2.0
2 /*
3 * Driver for STMicroelectronics STM32F7 I2C controller
4 *
5 * This I2C controller is described in the STM32F75xxx and STM32F74xxx Soc
6 * reference manual.
7 * Please see below a link to the documentation:
8 * http://www.st.com/resource/en/reference_manual/dm00124865.pdf
9 *
10 * Copyright (C) M'boumba Cedric Madianga 2017
11 * Copyright (C) STMicroelectronics 2017
12 * Author: M'boumba Cedric Madianga <cedric.madianga@gmail.com>
13 *
14 * This driver is based on i2c-stm32f4.c
15 *
16 */
17 #include <linux/clk.h>
18 #include <linux/delay.h>
19 #include <linux/err.h>
20 #include <linux/i2c.h>
21 #include <linux/i2c-smbus.h>
22 #include <linux/interrupt.h>
23 #include <linux/io.h>
24 #include <linux/iopoll.h>
25 #include <linux/mfd/syscon.h>
26 #include <linux/module.h>
27 #include <linux/of.h>
28 #include <linux/of_address.h>
29 #include <linux/of_platform.h>
30 #include <linux/platform_device.h>
31 #include <linux/pinctrl/consumer.h>
32 #include <linux/pm_runtime.h>
33 #include <linux/pm_wakeirq.h>
34 #include <linux/regmap.h>
35 #include <linux/reset.h>
36 #include <linux/slab.h>
37
38 #include "i2c-stm32.h"
39
40 /* STM32F7 I2C registers */
41 #define STM32F7_I2C_CR1 0x00
42 #define STM32F7_I2C_CR2 0x04
43 #define STM32F7_I2C_OAR1 0x08
44 #define STM32F7_I2C_OAR2 0x0C
45 #define STM32F7_I2C_PECR 0x20
46 #define STM32F7_I2C_TIMINGR 0x10
47 #define STM32F7_I2C_ISR 0x18
48 #define STM32F7_I2C_ICR 0x1C
49 #define STM32F7_I2C_RXDR 0x24
50 #define STM32F7_I2C_TXDR 0x28
51
52 /* STM32F7 I2C control 1 */
53 #define STM32_I2C_CR1_FMP BIT(24)
54 #define STM32F7_I2C_CR1_PECEN BIT(23)
55 #define STM32F7_I2C_CR1_ALERTEN BIT(22)
56 #define STM32F7_I2C_CR1_SMBHEN BIT(20)
57 #define STM32F7_I2C_CR1_WUPEN BIT(18)
58 #define STM32F7_I2C_CR1_SBC BIT(16)
59 #define STM32F7_I2C_CR1_RXDMAEN BIT(15)
60 #define STM32F7_I2C_CR1_TXDMAEN BIT(14)
61 #define STM32F7_I2C_CR1_ANFOFF BIT(12)
62 #define STM32F7_I2C_CR1_DNF_MASK GENMASK(11, 8)
63 #define STM32F7_I2C_CR1_DNF(n) (((n) & 0xf) << 8)
64 #define STM32F7_I2C_CR1_ERRIE BIT(7)
65 #define STM32F7_I2C_CR1_TCIE BIT(6)
66 #define STM32F7_I2C_CR1_STOPIE BIT(5)
67 #define STM32F7_I2C_CR1_NACKIE BIT(4)
68 #define STM32F7_I2C_CR1_ADDRIE BIT(3)
69 #define STM32F7_I2C_CR1_RXIE BIT(2)
70 #define STM32F7_I2C_CR1_TXIE BIT(1)
71 #define STM32F7_I2C_CR1_PE BIT(0)
72 #define STM32F7_I2C_ALL_IRQ_MASK (STM32F7_I2C_CR1_ERRIE \
73 | STM32F7_I2C_CR1_TCIE \
74 | STM32F7_I2C_CR1_STOPIE \
75 | STM32F7_I2C_CR1_NACKIE \
76 | STM32F7_I2C_CR1_RXIE \
77 | STM32F7_I2C_CR1_TXIE)
78 #define STM32F7_I2C_XFER_IRQ_MASK (STM32F7_I2C_CR1_TCIE \
79 | STM32F7_I2C_CR1_STOPIE \
80 | STM32F7_I2C_CR1_NACKIE \
81 | STM32F7_I2C_CR1_RXIE \
82 | STM32F7_I2C_CR1_TXIE)
83
84 /* STM32F7 I2C control 2 */
85 #define STM32F7_I2C_CR2_PECBYTE BIT(26)
86 #define STM32F7_I2C_CR2_RELOAD BIT(24)
87 #define STM32F7_I2C_CR2_NBYTES_MASK GENMASK(23, 16)
88 #define STM32F7_I2C_CR2_NBYTES(n) (((n) & 0xff) << 16)
89 #define STM32F7_I2C_CR2_NACK BIT(15)
90 #define STM32F7_I2C_CR2_STOP BIT(14)
91 #define STM32F7_I2C_CR2_START BIT(13)
92 #define STM32F7_I2C_CR2_HEAD10R BIT(12)
93 #define STM32F7_I2C_CR2_ADD10 BIT(11)
94 #define STM32F7_I2C_CR2_RD_WRN BIT(10)
95 #define STM32F7_I2C_CR2_SADD10_MASK GENMASK(9, 0)
96 #define STM32F7_I2C_CR2_SADD10(n) (((n) & \
97 STM32F7_I2C_CR2_SADD10_MASK))
98 #define STM32F7_I2C_CR2_SADD7_MASK GENMASK(7, 1)
99 #define STM32F7_I2C_CR2_SADD7(n) (((n) & 0x7f) << 1)
100
101 /* STM32F7 I2C Own Address 1 */
102 #define STM32F7_I2C_OAR1_OA1EN BIT(15)
103 #define STM32F7_I2C_OAR1_OA1MODE BIT(10)
104 #define STM32F7_I2C_OAR1_OA1_10_MASK GENMASK(9, 0)
105 #define STM32F7_I2C_OAR1_OA1_10(n) (((n) & \
106 STM32F7_I2C_OAR1_OA1_10_MASK))
107 #define STM32F7_I2C_OAR1_OA1_7_MASK GENMASK(7, 1)
108 #define STM32F7_I2C_OAR1_OA1_7(n) (((n) & 0x7f) << 1)
109 #define STM32F7_I2C_OAR1_MASK (STM32F7_I2C_OAR1_OA1_7_MASK \
110 | STM32F7_I2C_OAR1_OA1_10_MASK \
111 | STM32F7_I2C_OAR1_OA1EN \
112 | STM32F7_I2C_OAR1_OA1MODE)
113
114 /* STM32F7 I2C Own Address 2 */
115 #define STM32F7_I2C_OAR2_OA2EN BIT(15)
116 #define STM32F7_I2C_OAR2_OA2MSK_MASK GENMASK(10, 8)
117 #define STM32F7_I2C_OAR2_OA2MSK(n) (((n) & 0x7) << 8)
118 #define STM32F7_I2C_OAR2_OA2_7_MASK GENMASK(7, 1)
119 #define STM32F7_I2C_OAR2_OA2_7(n) (((n) & 0x7f) << 1)
120 #define STM32F7_I2C_OAR2_MASK (STM32F7_I2C_OAR2_OA2MSK_MASK \
121 | STM32F7_I2C_OAR2_OA2_7_MASK \
122 | STM32F7_I2C_OAR2_OA2EN)
123
124 /* STM32F7 I2C Interrupt Status */
125 #define STM32F7_I2C_ISR_ADDCODE_MASK GENMASK(23, 17)
126 #define STM32F7_I2C_ISR_ADDCODE_GET(n) \
127 (((n) & STM32F7_I2C_ISR_ADDCODE_MASK) >> 17)
128 #define STM32F7_I2C_ISR_DIR BIT(16)
129 #define STM32F7_I2C_ISR_BUSY BIT(15)
130 #define STM32F7_I2C_ISR_ALERT BIT(13)
131 #define STM32F7_I2C_ISR_PECERR BIT(11)
132 #define STM32F7_I2C_ISR_ARLO BIT(9)
133 #define STM32F7_I2C_ISR_BERR BIT(8)
134 #define STM32F7_I2C_ISR_TCR BIT(7)
135 #define STM32F7_I2C_ISR_TC BIT(6)
136 #define STM32F7_I2C_ISR_STOPF BIT(5)
137 #define STM32F7_I2C_ISR_NACKF BIT(4)
138 #define STM32F7_I2C_ISR_ADDR BIT(3)
139 #define STM32F7_I2C_ISR_RXNE BIT(2)
140 #define STM32F7_I2C_ISR_TXIS BIT(1)
141 #define STM32F7_I2C_ISR_TXE BIT(0)
142
143 /* STM32F7 I2C Interrupt Clear */
144 #define STM32F7_I2C_ICR_ALERTCF BIT(13)
145 #define STM32F7_I2C_ICR_PECCF BIT(11)
146 #define STM32F7_I2C_ICR_ARLOCF BIT(9)
147 #define STM32F7_I2C_ICR_BERRCF BIT(8)
148 #define STM32F7_I2C_ICR_STOPCF BIT(5)
149 #define STM32F7_I2C_ICR_NACKCF BIT(4)
150 #define STM32F7_I2C_ICR_ADDRCF BIT(3)
151
152 /* STM32F7 I2C Timing */
153 #define STM32F7_I2C_TIMINGR_PRESC(n) (((n) & 0xf) << 28)
154 #define STM32F7_I2C_TIMINGR_SCLDEL(n) (((n) & 0xf) << 20)
155 #define STM32F7_I2C_TIMINGR_SDADEL(n) (((n) & 0xf) << 16)
156 #define STM32F7_I2C_TIMINGR_SCLH(n) (((n) & 0xff) << 8)
157 #define STM32F7_I2C_TIMINGR_SCLL(n) ((n) & 0xff)
158
159 #define STM32F7_I2C_MAX_LEN 0xff
160 #define STM32F7_I2C_DMA_LEN_MIN 0x16
161 enum {
162 STM32F7_SLAVE_HOSTNOTIFY,
163 STM32F7_SLAVE_7_10_BITS_ADDR,
164 STM32F7_SLAVE_7_BITS_ADDR,
165 STM32F7_I2C_MAX_SLAVE
166 };
167
168 #define STM32F7_I2C_DNF_DEFAULT 0
169 #define STM32F7_I2C_DNF_MAX 15
170
171 #define STM32F7_I2C_ANALOG_FILTER_DELAY_MIN 50 /* ns */
172 #define STM32F7_I2C_ANALOG_FILTER_DELAY_MAX 260 /* ns */
173
174 #define STM32F7_I2C_RISE_TIME_DEFAULT 25 /* ns */
175 #define STM32F7_I2C_FALL_TIME_DEFAULT 10 /* ns */
176
177 #define STM32F7_PRESC_MAX BIT(4)
178 #define STM32F7_SCLDEL_MAX BIT(4)
179 #define STM32F7_SDADEL_MAX BIT(4)
180 #define STM32F7_SCLH_MAX BIT(8)
181 #define STM32F7_SCLL_MAX BIT(8)
182
183 #define STM32F7_AUTOSUSPEND_DELAY (HZ / 100)
184
185 /**
186 * struct stm32f7_i2c_regs - i2c f7 registers backup
187 * @cr1: Control register 1
188 * @cr2: Control register 2
189 * @oar1: Own address 1 register
190 * @oar2: Own address 2 register
191 * @tmgr: Timing register
192 */
193 struct stm32f7_i2c_regs {
194 u32 cr1;
195 u32 cr2;
196 u32 oar1;
197 u32 oar2;
198 u32 tmgr;
199 };
200
201 /**
202 * struct stm32f7_i2c_spec - private i2c specification timing
203 * @rate: I2C bus speed (Hz)
204 * @fall_max: Max fall time of both SDA and SCL signals (ns)
205 * @rise_max: Max rise time of both SDA and SCL signals (ns)
206 * @hddat_min: Min data hold time (ns)
207 * @vddat_max: Max data valid time (ns)
208 * @sudat_min: Min data setup time (ns)
209 * @l_min: Min low period of the SCL clock (ns)
210 * @h_min: Min high period of the SCL clock (ns)
211 */
212 struct stm32f7_i2c_spec {
213 u32 rate;
214 u32 fall_max;
215 u32 rise_max;
216 u32 hddat_min;
217 u32 vddat_max;
218 u32 sudat_min;
219 u32 l_min;
220 u32 h_min;
221 };
222
223 /**
224 * struct stm32f7_i2c_setup - private I2C timing setup parameters
225 * @speed_freq: I2C speed frequency (Hz)
226 * @clock_src: I2C clock source frequency (Hz)
227 * @rise_time: Rise time (ns)
228 * @fall_time: Fall time (ns)
229 * @fmp_clr_offset: Fast Mode Plus clear register offset from set register
230 * @single_it_line: Only a single IT line is used for both events/errors
231 * @fmp_cr1_bit: Fast Mode Plus control is done via a bit in CR1
232 */
233 struct stm32f7_i2c_setup {
234 u32 speed_freq;
235 u32 clock_src;
236 u32 rise_time;
237 u32 fall_time;
238 u32 fmp_clr_offset;
239 bool single_it_line;
240 bool fmp_cr1_bit;
241 };
242
243 /**
244 * struct stm32f7_i2c_timings - private I2C output parameters
245 * @node: List entry
246 * @presc: Prescaler value
247 * @scldel: Data setup time
248 * @sdadel: Data hold time
249 * @sclh: SCL high period (master mode)
250 * @scll: SCL low period (master mode)
251 */
252 struct stm32f7_i2c_timings {
253 struct list_head node;
254 u8 presc;
255 u8 scldel;
256 u8 sdadel;
257 u8 sclh;
258 u8 scll;
259 };
260
261 /**
262 * struct stm32f7_i2c_msg - client specific data
263 * @addr: 8-bit or 10-bit slave addr, including r/w bit
264 * @count: number of bytes to be transferred
265 * @buf: data buffer
266 * @result: result of the transfer
267 * @stop: last I2C msg to be sent, i.e. STOP to be generated
268 * @smbus: boolean to know if the I2C IP is used in SMBus mode
269 * @size: type of SMBus protocol
270 * @read_write: direction of SMBus protocol
271 * SMBus block read and SMBus block write - block read process call protocols
272 * @smbus_buf: buffer to be used for SMBus protocol transfer. It will
273 * contain a maximum of 32 bytes of data + byte command + byte count + PEC
274 * This buffer has to be 32-bit aligned to be compliant with memory address
275 * register in DMA mode.
276 */
277 struct stm32f7_i2c_msg {
278 u16 addr;
279 u32 count;
280 u8 *buf;
281 int result;
282 bool stop;
283 bool smbus;
284 int size;
285 char read_write;
286 u8 smbus_buf[I2C_SMBUS_BLOCK_MAX + 3] __aligned(4);
287 };
288
289 /**
290 * struct stm32f7_i2c_alert - SMBus alert specific data
291 * @setup: platform data for the smbus_alert i2c client
292 * @ara: I2C slave device used to respond to the SMBus Alert with Alert
293 * Response Address
294 */
295 struct stm32f7_i2c_alert {
296 struct i2c_smbus_alert_setup setup;
297 struct i2c_client *ara;
298 };
299
300 /**
301 * struct stm32f7_i2c_dev - private data of the controller
302 * @adap: I2C adapter for this controller
303 * @dev: device for this controller
304 * @base: virtual memory area
305 * @complete: completion of I2C message
306 * @clk: hw i2c clock
307 * @bus_rate: I2C clock frequency of the controller
308 * @msg: Pointer to data to be written
309 * @msg_num: number of I2C messages to be executed
310 * @msg_id: message identifiant
311 * @f7_msg: customized i2c msg for driver usage
312 * @setup: I2C timing input setup
313 * @timing: I2C computed timings
314 * @slave: list of slave devices registered on the I2C bus
315 * @slave_running: slave device currently used
316 * @backup_regs: backup of i2c controller registers (for suspend/resume)
317 * @slave_dir: transfer direction for the current slave device
318 * @master_mode: boolean to know in which mode the I2C is running (master or
319 * slave)
320 * @dma: dma data
321 * @use_dma: boolean to know if dma is used in the current transfer
322 * @regmap: holds SYSCFG phandle for Fast Mode Plus bits
323 * @fmp_sreg: register address for setting Fast Mode Plus bits
324 * @fmp_creg: register address for clearing Fast Mode Plus bits
325 * @fmp_mask: mask for Fast Mode Plus bits in set register
326 * @wakeup_src: boolean to know if the device is a wakeup source
327 * @smbus_mode: states that the controller is configured in SMBus mode
328 * @host_notify_client: SMBus host-notify client
329 * @analog_filter: boolean to indicate enabling of the analog filter
330 * @dnf_dt: value of digital filter requested via dt
331 * @dnf: value of digital filter to apply
332 * @alert: SMBus alert specific data
333 * @atomic: boolean indicating that current transfer is atomic
334 */
335 struct stm32f7_i2c_dev {
336 struct i2c_adapter adap;
337 struct device *dev;
338 void __iomem *base;
339 struct completion complete;
340 struct clk *clk;
341 unsigned int bus_rate;
342 struct i2c_msg *msg;
343 unsigned int msg_num;
344 unsigned int msg_id;
345 struct stm32f7_i2c_msg f7_msg;
346 struct stm32f7_i2c_setup setup;
347 struct stm32f7_i2c_timings timing;
348 struct i2c_client *slave[STM32F7_I2C_MAX_SLAVE];
349 struct i2c_client *slave_running;
350 struct stm32f7_i2c_regs backup_regs;
351 u32 slave_dir;
352 bool master_mode;
353 struct stm32_i2c_dma *dma;
354 bool use_dma;
355 struct regmap *regmap;
356 u32 fmp_sreg;
357 u32 fmp_creg;
358 u32 fmp_mask;
359 bool wakeup_src;
360 bool smbus_mode;
361 struct i2c_client *host_notify_client;
362 bool analog_filter;
363 u32 dnf_dt;
364 u32 dnf;
365 struct stm32f7_i2c_alert *alert;
366 bool atomic;
367 };
368
369 /*
370 * All these values are coming from I2C Specification, Version 6.0, 4th of
371 * April 2014.
372 *
373 * Table10. Characteristics of the SDA and SCL bus lines for Standard, Fast,
374 * and Fast-mode Plus I2C-bus devices
375 */
376 static struct stm32f7_i2c_spec stm32f7_i2c_specs[] = {
377 {
378 .rate = I2C_MAX_STANDARD_MODE_FREQ,
379 .fall_max = 300,
380 .rise_max = 1000,
381 .hddat_min = 0,
382 .vddat_max = 3450,
383 .sudat_min = 250,
384 .l_min = 4700,
385 .h_min = 4000,
386 },
387 {
388 .rate = I2C_MAX_FAST_MODE_FREQ,
389 .fall_max = 300,
390 .rise_max = 300,
391 .hddat_min = 0,
392 .vddat_max = 900,
393 .sudat_min = 100,
394 .l_min = 1300,
395 .h_min = 600,
396 },
397 {
398 .rate = I2C_MAX_FAST_MODE_PLUS_FREQ,
399 .fall_max = 100,
400 .rise_max = 120,
401 .hddat_min = 0,
402 .vddat_max = 450,
403 .sudat_min = 50,
404 .l_min = 500,
405 .h_min = 260,
406 },
407 };
408
409 static const struct stm32f7_i2c_setup stm32f7_setup = {
410 .rise_time = STM32F7_I2C_RISE_TIME_DEFAULT,
411 .fall_time = STM32F7_I2C_FALL_TIME_DEFAULT,
412 };
413
414 static const struct stm32f7_i2c_setup stm32mp15_setup = {
415 .rise_time = STM32F7_I2C_RISE_TIME_DEFAULT,
416 .fall_time = STM32F7_I2C_FALL_TIME_DEFAULT,
417 .fmp_clr_offset = 0x40,
418 };
419
420 static const struct stm32f7_i2c_setup stm32mp13_setup = {
421 .rise_time = STM32F7_I2C_RISE_TIME_DEFAULT,
422 .fall_time = STM32F7_I2C_FALL_TIME_DEFAULT,
423 .fmp_clr_offset = 0x4,
424 };
425
426 static const struct stm32f7_i2c_setup stm32mp25_setup = {
427 .rise_time = STM32F7_I2C_RISE_TIME_DEFAULT,
428 .fall_time = STM32F7_I2C_FALL_TIME_DEFAULT,
429 .single_it_line = true,
430 .fmp_cr1_bit = true,
431 };
432
stm32f7_i2c_set_bits(void __iomem * reg,u32 mask)433 static inline void stm32f7_i2c_set_bits(void __iomem *reg, u32 mask)
434 {
435 writel_relaxed(readl_relaxed(reg) | mask, reg);
436 }
437
stm32f7_i2c_clr_bits(void __iomem * reg,u32 mask)438 static inline void stm32f7_i2c_clr_bits(void __iomem *reg, u32 mask)
439 {
440 writel_relaxed(readl_relaxed(reg) & ~mask, reg);
441 }
442
stm32f7_i2c_disable_irq(struct stm32f7_i2c_dev * i2c_dev,u32 mask)443 static void stm32f7_i2c_disable_irq(struct stm32f7_i2c_dev *i2c_dev, u32 mask)
444 {
445 stm32f7_i2c_clr_bits(i2c_dev->base + STM32F7_I2C_CR1, mask);
446 }
447
stm32f7_get_specs(u32 rate)448 static struct stm32f7_i2c_spec *stm32f7_get_specs(u32 rate)
449 {
450 int i;
451
452 for (i = 0; i < ARRAY_SIZE(stm32f7_i2c_specs); i++)
453 if (rate <= stm32f7_i2c_specs[i].rate)
454 return &stm32f7_i2c_specs[i];
455
456 return ERR_PTR(-EINVAL);
457 }
458
459 #define RATE_MIN(rate) ((rate) * 8 / 10)
stm32f7_i2c_compute_timing(struct stm32f7_i2c_dev * i2c_dev,struct stm32f7_i2c_setup * setup,struct stm32f7_i2c_timings * output)460 static int stm32f7_i2c_compute_timing(struct stm32f7_i2c_dev *i2c_dev,
461 struct stm32f7_i2c_setup *setup,
462 struct stm32f7_i2c_timings *output)
463 {
464 struct stm32f7_i2c_spec *specs;
465 u32 p_prev = STM32F7_PRESC_MAX;
466 u32 i2cclk = DIV_ROUND_CLOSEST(NSEC_PER_SEC,
467 setup->clock_src);
468 u32 i2cbus = DIV_ROUND_CLOSEST(NSEC_PER_SEC,
469 setup->speed_freq);
470 u32 clk_error_prev = i2cbus;
471 u32 tsync;
472 u32 af_delay_min, af_delay_max;
473 u32 dnf_delay;
474 u32 clk_min, clk_max;
475 int sdadel_min, sdadel_max;
476 int scldel_min;
477 struct stm32f7_i2c_timings *v, *_v, *s;
478 struct list_head solutions;
479 u16 p, l, a, h;
480 int ret = 0;
481
482 specs = stm32f7_get_specs(setup->speed_freq);
483 if (specs == ERR_PTR(-EINVAL)) {
484 dev_err(i2c_dev->dev, "speed out of bound {%d}\n",
485 setup->speed_freq);
486 return -EINVAL;
487 }
488
489 if ((setup->rise_time > specs->rise_max) ||
490 (setup->fall_time > specs->fall_max)) {
491 dev_err(i2c_dev->dev,
492 "timings out of bound Rise{%d>%d}/Fall{%d>%d}\n",
493 setup->rise_time, specs->rise_max,
494 setup->fall_time, specs->fall_max);
495 return -EINVAL;
496 }
497
498 i2c_dev->dnf = DIV_ROUND_CLOSEST(i2c_dev->dnf_dt, i2cclk);
499 if (i2c_dev->dnf > STM32F7_I2C_DNF_MAX) {
500 dev_err(i2c_dev->dev,
501 "DNF out of bound %d/%d\n",
502 i2c_dev->dnf * i2cclk, STM32F7_I2C_DNF_MAX * i2cclk);
503 return -EINVAL;
504 }
505
506 /* Analog and Digital Filters */
507 af_delay_min =
508 (i2c_dev->analog_filter ?
509 STM32F7_I2C_ANALOG_FILTER_DELAY_MIN : 0);
510 af_delay_max =
511 (i2c_dev->analog_filter ?
512 STM32F7_I2C_ANALOG_FILTER_DELAY_MAX : 0);
513 dnf_delay = i2c_dev->dnf * i2cclk;
514
515 sdadel_min = specs->hddat_min + setup->fall_time -
516 af_delay_min - (i2c_dev->dnf + 3) * i2cclk;
517
518 sdadel_max = specs->vddat_max - setup->rise_time -
519 af_delay_max - (i2c_dev->dnf + 4) * i2cclk;
520
521 scldel_min = setup->rise_time + specs->sudat_min;
522
523 if (sdadel_min < 0)
524 sdadel_min = 0;
525 if (sdadel_max < 0)
526 sdadel_max = 0;
527
528 dev_dbg(i2c_dev->dev, "SDADEL(min/max): %i/%i, SCLDEL(Min): %i\n",
529 sdadel_min, sdadel_max, scldel_min);
530
531 INIT_LIST_HEAD(&solutions);
532 /* Compute possible values for PRESC, SCLDEL and SDADEL */
533 for (p = 0; p < STM32F7_PRESC_MAX; p++) {
534 for (l = 0; l < STM32F7_SCLDEL_MAX; l++) {
535 u32 scldel = (l + 1) * (p + 1) * i2cclk;
536
537 if (scldel < scldel_min)
538 continue;
539
540 for (a = 0; a < STM32F7_SDADEL_MAX; a++) {
541 u32 sdadel = (a * (p + 1) + 1) * i2cclk;
542
543 if (((sdadel >= sdadel_min) &&
544 (sdadel <= sdadel_max)) &&
545 (p != p_prev)) {
546 v = kmalloc(sizeof(*v), GFP_KERNEL);
547 if (!v) {
548 ret = -ENOMEM;
549 goto exit;
550 }
551
552 v->presc = p;
553 v->scldel = l;
554 v->sdadel = a;
555 p_prev = p;
556
557 list_add_tail(&v->node,
558 &solutions);
559 break;
560 }
561 }
562
563 if (p_prev == p)
564 break;
565 }
566 }
567
568 if (list_empty(&solutions)) {
569 dev_err(i2c_dev->dev, "no Prescaler solution\n");
570 ret = -EPERM;
571 goto exit;
572 }
573
574 tsync = af_delay_min + dnf_delay + (2 * i2cclk);
575 s = NULL;
576 clk_max = NSEC_PER_SEC / RATE_MIN(setup->speed_freq);
577 clk_min = NSEC_PER_SEC / setup->speed_freq;
578
579 /*
580 * Among Prescaler possibilities discovered above figures out SCL Low
581 * and High Period. Provided:
582 * - SCL Low Period has to be higher than SCL Clock Low Period
583 * defined by I2C Specification. I2C Clock has to be lower than
584 * (SCL Low Period - Analog/Digital filters) / 4.
585 * - SCL High Period has to be lower than SCL Clock High Period
586 * defined by I2C Specification
587 * - I2C Clock has to be lower than SCL High Period
588 */
589 list_for_each_entry(v, &solutions, node) {
590 u32 prescaler = (v->presc + 1) * i2cclk;
591
592 for (l = 0; l < STM32F7_SCLL_MAX; l++) {
593 u32 tscl_l = (l + 1) * prescaler + tsync;
594
595 if ((tscl_l < specs->l_min) ||
596 (i2cclk >=
597 ((tscl_l - af_delay_min - dnf_delay) / 4))) {
598 continue;
599 }
600
601 for (h = 0; h < STM32F7_SCLH_MAX; h++) {
602 u32 tscl_h = (h + 1) * prescaler + tsync;
603 u32 tscl = tscl_l + tscl_h +
604 setup->rise_time + setup->fall_time;
605
606 if ((tscl >= clk_min) && (tscl <= clk_max) &&
607 (tscl_h >= specs->h_min) &&
608 (i2cclk < tscl_h)) {
609 int clk_error = tscl - i2cbus;
610
611 if (clk_error < 0)
612 clk_error = -clk_error;
613
614 if (clk_error < clk_error_prev) {
615 clk_error_prev = clk_error;
616 v->scll = l;
617 v->sclh = h;
618 s = v;
619 }
620 }
621 }
622 }
623 }
624
625 if (!s) {
626 dev_err(i2c_dev->dev, "no solution at all\n");
627 ret = -EPERM;
628 goto exit;
629 }
630
631 output->presc = s->presc;
632 output->scldel = s->scldel;
633 output->sdadel = s->sdadel;
634 output->scll = s->scll;
635 output->sclh = s->sclh;
636
637 dev_dbg(i2c_dev->dev,
638 "Presc: %i, scldel: %i, sdadel: %i, scll: %i, sclh: %i\n",
639 output->presc,
640 output->scldel, output->sdadel,
641 output->scll, output->sclh);
642
643 exit:
644 /* Release list and memory */
645 list_for_each_entry_safe(v, _v, &solutions, node) {
646 list_del(&v->node);
647 kfree(v);
648 }
649
650 return ret;
651 }
652
stm32f7_get_lower_rate(u32 rate)653 static u32 stm32f7_get_lower_rate(u32 rate)
654 {
655 int i = ARRAY_SIZE(stm32f7_i2c_specs);
656
657 while (--i)
658 if (stm32f7_i2c_specs[i].rate < rate)
659 break;
660
661 return stm32f7_i2c_specs[i].rate;
662 }
663
stm32f7_i2c_setup_timing(struct stm32f7_i2c_dev * i2c_dev,struct stm32f7_i2c_setup * setup)664 static int stm32f7_i2c_setup_timing(struct stm32f7_i2c_dev *i2c_dev,
665 struct stm32f7_i2c_setup *setup)
666 {
667 struct i2c_timings timings, *t = &timings;
668 int ret = 0;
669
670 t->bus_freq_hz = I2C_MAX_STANDARD_MODE_FREQ;
671 t->scl_rise_ns = i2c_dev->setup.rise_time;
672 t->scl_fall_ns = i2c_dev->setup.fall_time;
673
674 i2c_parse_fw_timings(i2c_dev->dev, t, false);
675
676 if (t->bus_freq_hz > I2C_MAX_FAST_MODE_PLUS_FREQ) {
677 dev_err(i2c_dev->dev, "Invalid bus speed (%i>%i)\n",
678 t->bus_freq_hz, I2C_MAX_FAST_MODE_PLUS_FREQ);
679 return -EINVAL;
680 }
681
682 setup->speed_freq = t->bus_freq_hz;
683 i2c_dev->setup.rise_time = t->scl_rise_ns;
684 i2c_dev->setup.fall_time = t->scl_fall_ns;
685 i2c_dev->dnf_dt = t->digital_filter_width_ns;
686 setup->clock_src = clk_get_rate(i2c_dev->clk);
687
688 if (!setup->clock_src) {
689 dev_err(i2c_dev->dev, "clock rate is 0\n");
690 return -EINVAL;
691 }
692
693 if (!of_property_read_bool(i2c_dev->dev->of_node, "i2c-digital-filter"))
694 i2c_dev->dnf_dt = STM32F7_I2C_DNF_DEFAULT;
695
696 do {
697 ret = stm32f7_i2c_compute_timing(i2c_dev, setup,
698 &i2c_dev->timing);
699 if (ret) {
700 dev_err(i2c_dev->dev,
701 "failed to compute I2C timings.\n");
702 if (setup->speed_freq <= I2C_MAX_STANDARD_MODE_FREQ)
703 break;
704 setup->speed_freq =
705 stm32f7_get_lower_rate(setup->speed_freq);
706 dev_warn(i2c_dev->dev,
707 "downgrade I2C Speed Freq to (%i)\n",
708 setup->speed_freq);
709 }
710 } while (ret);
711
712 if (ret) {
713 dev_err(i2c_dev->dev, "Impossible to compute I2C timings.\n");
714 return ret;
715 }
716
717 i2c_dev->analog_filter = of_property_read_bool(i2c_dev->dev->of_node,
718 "i2c-analog-filter");
719
720 dev_dbg(i2c_dev->dev, "I2C Speed(%i), Clk Source(%i)\n",
721 setup->speed_freq, setup->clock_src);
722 dev_dbg(i2c_dev->dev, "I2C Rise(%i) and Fall(%i) Time\n",
723 setup->rise_time, setup->fall_time);
724 dev_dbg(i2c_dev->dev, "I2C Analog Filter(%s), DNF(%i)\n",
725 (i2c_dev->analog_filter ? "On" : "Off"), i2c_dev->dnf);
726
727 i2c_dev->bus_rate = setup->speed_freq;
728
729 return 0;
730 }
731
stm32f7_i2c_disable_dma_req(struct stm32f7_i2c_dev * i2c_dev)732 static void stm32f7_i2c_disable_dma_req(struct stm32f7_i2c_dev *i2c_dev)
733 {
734 void __iomem *base = i2c_dev->base;
735 u32 mask = STM32F7_I2C_CR1_RXDMAEN | STM32F7_I2C_CR1_TXDMAEN;
736
737 stm32f7_i2c_clr_bits(base + STM32F7_I2C_CR1, mask);
738 }
739
stm32f7_i2c_dma_callback(void * arg)740 static void stm32f7_i2c_dma_callback(void *arg)
741 {
742 struct stm32f7_i2c_dev *i2c_dev = (struct stm32f7_i2c_dev *)arg;
743 struct stm32_i2c_dma *dma = i2c_dev->dma;
744 struct device *dev = dma->chan_using->device->dev;
745
746 stm32f7_i2c_disable_dma_req(i2c_dev);
747 dma_unmap_single(dev, dma->dma_buf, dma->dma_len, dma->dma_data_dir);
748 complete(&dma->dma_complete);
749 }
750
stm32f7_i2c_hw_config(struct stm32f7_i2c_dev * i2c_dev)751 static void stm32f7_i2c_hw_config(struct stm32f7_i2c_dev *i2c_dev)
752 {
753 struct stm32f7_i2c_timings *t = &i2c_dev->timing;
754 u32 timing = 0;
755
756 /* Timing settings */
757 timing |= STM32F7_I2C_TIMINGR_PRESC(t->presc);
758 timing |= STM32F7_I2C_TIMINGR_SCLDEL(t->scldel);
759 timing |= STM32F7_I2C_TIMINGR_SDADEL(t->sdadel);
760 timing |= STM32F7_I2C_TIMINGR_SCLH(t->sclh);
761 timing |= STM32F7_I2C_TIMINGR_SCLL(t->scll);
762 writel_relaxed(timing, i2c_dev->base + STM32F7_I2C_TIMINGR);
763
764 /* Configure the Analog Filter */
765 if (i2c_dev->analog_filter)
766 stm32f7_i2c_clr_bits(i2c_dev->base + STM32F7_I2C_CR1,
767 STM32F7_I2C_CR1_ANFOFF);
768 else
769 stm32f7_i2c_set_bits(i2c_dev->base + STM32F7_I2C_CR1,
770 STM32F7_I2C_CR1_ANFOFF);
771
772 /* Program the Digital Filter */
773 stm32f7_i2c_clr_bits(i2c_dev->base + STM32F7_I2C_CR1,
774 STM32F7_I2C_CR1_DNF_MASK);
775 stm32f7_i2c_set_bits(i2c_dev->base + STM32F7_I2C_CR1,
776 STM32F7_I2C_CR1_DNF(i2c_dev->dnf));
777
778 stm32f7_i2c_set_bits(i2c_dev->base + STM32F7_I2C_CR1,
779 STM32F7_I2C_CR1_PE);
780 }
781
stm32f7_i2c_write_tx_data(struct stm32f7_i2c_dev * i2c_dev)782 static void stm32f7_i2c_write_tx_data(struct stm32f7_i2c_dev *i2c_dev)
783 {
784 struct stm32f7_i2c_msg *f7_msg = &i2c_dev->f7_msg;
785 void __iomem *base = i2c_dev->base;
786
787 if (f7_msg->count) {
788 writeb_relaxed(*f7_msg->buf++, base + STM32F7_I2C_TXDR);
789 f7_msg->count--;
790 }
791 }
792
stm32f7_i2c_read_rx_data(struct stm32f7_i2c_dev * i2c_dev)793 static void stm32f7_i2c_read_rx_data(struct stm32f7_i2c_dev *i2c_dev)
794 {
795 struct stm32f7_i2c_msg *f7_msg = &i2c_dev->f7_msg;
796 void __iomem *base = i2c_dev->base;
797
798 if (f7_msg->count) {
799 *f7_msg->buf++ = readb_relaxed(base + STM32F7_I2C_RXDR);
800 f7_msg->count--;
801 } else {
802 /* Flush RX buffer has no data is expected */
803 readb_relaxed(base + STM32F7_I2C_RXDR);
804 }
805 }
806
stm32f7_i2c_reload(struct stm32f7_i2c_dev * i2c_dev)807 static void stm32f7_i2c_reload(struct stm32f7_i2c_dev *i2c_dev)
808 {
809 struct stm32f7_i2c_msg *f7_msg = &i2c_dev->f7_msg;
810 u32 cr2;
811
812 if (i2c_dev->use_dma)
813 f7_msg->count -= STM32F7_I2C_MAX_LEN;
814
815 cr2 = readl_relaxed(i2c_dev->base + STM32F7_I2C_CR2);
816
817 cr2 &= ~STM32F7_I2C_CR2_NBYTES_MASK;
818 if (f7_msg->count > STM32F7_I2C_MAX_LEN) {
819 cr2 |= STM32F7_I2C_CR2_NBYTES(STM32F7_I2C_MAX_LEN);
820 } else {
821 cr2 &= ~STM32F7_I2C_CR2_RELOAD;
822 cr2 |= STM32F7_I2C_CR2_NBYTES(f7_msg->count);
823 }
824
825 writel_relaxed(cr2, i2c_dev->base + STM32F7_I2C_CR2);
826 }
827
stm32f7_i2c_smbus_reload(struct stm32f7_i2c_dev * i2c_dev)828 static void stm32f7_i2c_smbus_reload(struct stm32f7_i2c_dev *i2c_dev)
829 {
830 struct stm32f7_i2c_msg *f7_msg = &i2c_dev->f7_msg;
831 u32 cr2;
832 u8 *val;
833
834 /*
835 * For I2C_SMBUS_BLOCK_DATA && I2C_SMBUS_BLOCK_PROC_CALL, the first
836 * data received inform us how many data will follow.
837 */
838 stm32f7_i2c_read_rx_data(i2c_dev);
839
840 /*
841 * Update NBYTES with the value read to continue the transfer
842 */
843 val = f7_msg->buf - sizeof(u8);
844 f7_msg->count = *val;
845 cr2 = readl_relaxed(i2c_dev->base + STM32F7_I2C_CR2);
846 cr2 &= ~(STM32F7_I2C_CR2_NBYTES_MASK | STM32F7_I2C_CR2_RELOAD);
847 cr2 |= STM32F7_I2C_CR2_NBYTES(f7_msg->count);
848 writel_relaxed(cr2, i2c_dev->base + STM32F7_I2C_CR2);
849 }
850
stm32f7_i2c_release_bus(struct i2c_adapter * i2c_adap)851 static void stm32f7_i2c_release_bus(struct i2c_adapter *i2c_adap)
852 {
853 struct stm32f7_i2c_dev *i2c_dev = i2c_get_adapdata(i2c_adap);
854
855 stm32f7_i2c_clr_bits(i2c_dev->base + STM32F7_I2C_CR1,
856 STM32F7_I2C_CR1_PE);
857
858 stm32f7_i2c_hw_config(i2c_dev);
859 }
860
stm32f7_i2c_wait_free_bus(struct stm32f7_i2c_dev * i2c_dev)861 static int stm32f7_i2c_wait_free_bus(struct stm32f7_i2c_dev *i2c_dev)
862 {
863 u32 status;
864 int ret;
865
866 ret = readl_relaxed_poll_timeout(i2c_dev->base + STM32F7_I2C_ISR,
867 status,
868 !(status & STM32F7_I2C_ISR_BUSY),
869 10, 1000);
870 if (!ret)
871 return 0;
872
873 stm32f7_i2c_release_bus(&i2c_dev->adap);
874
875 return -EBUSY;
876 }
877
stm32f7_i2c_xfer_msg(struct stm32f7_i2c_dev * i2c_dev,struct i2c_msg * msg)878 static void stm32f7_i2c_xfer_msg(struct stm32f7_i2c_dev *i2c_dev,
879 struct i2c_msg *msg)
880 {
881 struct stm32f7_i2c_msg *f7_msg = &i2c_dev->f7_msg;
882 void __iomem *base = i2c_dev->base;
883 u32 cr1, cr2;
884 int ret;
885
886 f7_msg->addr = msg->addr;
887 f7_msg->buf = msg->buf;
888 f7_msg->count = msg->len;
889 f7_msg->result = 0;
890 f7_msg->stop = (i2c_dev->msg_id >= i2c_dev->msg_num - 1);
891
892 reinit_completion(&i2c_dev->complete);
893
894 cr1 = readl_relaxed(base + STM32F7_I2C_CR1);
895 cr2 = readl_relaxed(base + STM32F7_I2C_CR2);
896
897 /* Set transfer direction */
898 cr2 &= ~STM32F7_I2C_CR2_RD_WRN;
899 if (msg->flags & I2C_M_RD)
900 cr2 |= STM32F7_I2C_CR2_RD_WRN;
901
902 /* Set slave address */
903 cr2 &= ~(STM32F7_I2C_CR2_HEAD10R | STM32F7_I2C_CR2_ADD10);
904 if (msg->flags & I2C_M_TEN) {
905 cr2 &= ~STM32F7_I2C_CR2_SADD10_MASK;
906 cr2 |= STM32F7_I2C_CR2_SADD10(f7_msg->addr);
907 cr2 |= STM32F7_I2C_CR2_ADD10;
908 } else {
909 cr2 &= ~STM32F7_I2C_CR2_SADD7_MASK;
910 cr2 |= STM32F7_I2C_CR2_SADD7(f7_msg->addr);
911 }
912
913 /* Set nb bytes to transfer and reload if needed */
914 cr2 &= ~(STM32F7_I2C_CR2_NBYTES_MASK | STM32F7_I2C_CR2_RELOAD);
915 if (f7_msg->count > STM32F7_I2C_MAX_LEN) {
916 cr2 |= STM32F7_I2C_CR2_NBYTES(STM32F7_I2C_MAX_LEN);
917 cr2 |= STM32F7_I2C_CR2_RELOAD;
918 } else {
919 cr2 |= STM32F7_I2C_CR2_NBYTES(f7_msg->count);
920 }
921
922 /* Enable NACK, STOP, error and transfer complete interrupts */
923 cr1 |= STM32F7_I2C_CR1_ERRIE | STM32F7_I2C_CR1_TCIE |
924 STM32F7_I2C_CR1_STOPIE | STM32F7_I2C_CR1_NACKIE;
925
926 /* Clear DMA req and TX/RX interrupt */
927 cr1 &= ~(STM32F7_I2C_CR1_RXIE | STM32F7_I2C_CR1_TXIE |
928 STM32F7_I2C_CR1_RXDMAEN | STM32F7_I2C_CR1_TXDMAEN);
929
930 /* Configure DMA or enable RX/TX interrupt */
931 i2c_dev->use_dma = false;
932 if (i2c_dev->dma && f7_msg->count >= STM32F7_I2C_DMA_LEN_MIN
933 && !i2c_dev->atomic) {
934 ret = stm32_i2c_prep_dma_xfer(i2c_dev->dev, i2c_dev->dma,
935 msg->flags & I2C_M_RD,
936 f7_msg->count, f7_msg->buf,
937 stm32f7_i2c_dma_callback,
938 i2c_dev);
939 if (!ret)
940 i2c_dev->use_dma = true;
941 else
942 dev_warn(i2c_dev->dev, "can't use DMA\n");
943 }
944
945 if (!i2c_dev->use_dma) {
946 if (msg->flags & I2C_M_RD)
947 cr1 |= STM32F7_I2C_CR1_RXIE;
948 else
949 cr1 |= STM32F7_I2C_CR1_TXIE;
950 } else {
951 if (msg->flags & I2C_M_RD)
952 cr1 |= STM32F7_I2C_CR1_RXDMAEN;
953 else
954 cr1 |= STM32F7_I2C_CR1_TXDMAEN;
955 }
956
957 if (i2c_dev->atomic)
958 cr1 &= ~STM32F7_I2C_ALL_IRQ_MASK; /* Disable all interrupts */
959
960 /* Configure Start/Repeated Start */
961 cr2 |= STM32F7_I2C_CR2_START;
962
963 i2c_dev->master_mode = true;
964
965 /* Write configurations registers */
966 writel_relaxed(cr1, base + STM32F7_I2C_CR1);
967 writel_relaxed(cr2, base + STM32F7_I2C_CR2);
968 }
969
stm32f7_i2c_smbus_xfer_msg(struct stm32f7_i2c_dev * i2c_dev,unsigned short flags,u8 command,union i2c_smbus_data * data)970 static int stm32f7_i2c_smbus_xfer_msg(struct stm32f7_i2c_dev *i2c_dev,
971 unsigned short flags, u8 command,
972 union i2c_smbus_data *data)
973 {
974 struct stm32f7_i2c_msg *f7_msg = &i2c_dev->f7_msg;
975 struct device *dev = i2c_dev->dev;
976 void __iomem *base = i2c_dev->base;
977 u32 cr1, cr2;
978 int i, ret;
979
980 f7_msg->result = 0;
981 reinit_completion(&i2c_dev->complete);
982
983 cr2 = readl_relaxed(base + STM32F7_I2C_CR2);
984 cr1 = readl_relaxed(base + STM32F7_I2C_CR1);
985
986 /* Set transfer direction */
987 cr2 &= ~STM32F7_I2C_CR2_RD_WRN;
988 if (f7_msg->read_write)
989 cr2 |= STM32F7_I2C_CR2_RD_WRN;
990
991 /* Set slave address */
992 cr2 &= ~(STM32F7_I2C_CR2_ADD10 | STM32F7_I2C_CR2_SADD7_MASK);
993 cr2 |= STM32F7_I2C_CR2_SADD7(f7_msg->addr);
994
995 f7_msg->smbus_buf[0] = command;
996 switch (f7_msg->size) {
997 case I2C_SMBUS_QUICK:
998 f7_msg->stop = true;
999 f7_msg->count = 0;
1000 break;
1001 case I2C_SMBUS_BYTE:
1002 f7_msg->stop = true;
1003 f7_msg->count = 1;
1004 break;
1005 case I2C_SMBUS_BYTE_DATA:
1006 if (f7_msg->read_write) {
1007 f7_msg->stop = false;
1008 f7_msg->count = 1;
1009 cr2 &= ~STM32F7_I2C_CR2_RD_WRN;
1010 } else {
1011 f7_msg->stop = true;
1012 f7_msg->count = 2;
1013 f7_msg->smbus_buf[1] = data->byte;
1014 }
1015 break;
1016 case I2C_SMBUS_WORD_DATA:
1017 if (f7_msg->read_write) {
1018 f7_msg->stop = false;
1019 f7_msg->count = 1;
1020 cr2 &= ~STM32F7_I2C_CR2_RD_WRN;
1021 } else {
1022 f7_msg->stop = true;
1023 f7_msg->count = 3;
1024 f7_msg->smbus_buf[1] = data->word & 0xff;
1025 f7_msg->smbus_buf[2] = data->word >> 8;
1026 }
1027 break;
1028 case I2C_SMBUS_BLOCK_DATA:
1029 if (f7_msg->read_write) {
1030 f7_msg->stop = false;
1031 f7_msg->count = 1;
1032 cr2 &= ~STM32F7_I2C_CR2_RD_WRN;
1033 } else {
1034 f7_msg->stop = true;
1035 if (data->block[0] > I2C_SMBUS_BLOCK_MAX ||
1036 !data->block[0]) {
1037 dev_err(dev, "Invalid block write size %d\n",
1038 data->block[0]);
1039 return -EINVAL;
1040 }
1041 f7_msg->count = data->block[0] + 2;
1042 for (i = 1; i < f7_msg->count; i++)
1043 f7_msg->smbus_buf[i] = data->block[i - 1];
1044 }
1045 break;
1046 case I2C_SMBUS_PROC_CALL:
1047 f7_msg->stop = false;
1048 f7_msg->count = 3;
1049 f7_msg->smbus_buf[1] = data->word & 0xff;
1050 f7_msg->smbus_buf[2] = data->word >> 8;
1051 cr2 &= ~STM32F7_I2C_CR2_RD_WRN;
1052 f7_msg->read_write = I2C_SMBUS_READ;
1053 break;
1054 case I2C_SMBUS_BLOCK_PROC_CALL:
1055 f7_msg->stop = false;
1056 if (data->block[0] > I2C_SMBUS_BLOCK_MAX - 1) {
1057 dev_err(dev, "Invalid block write size %d\n",
1058 data->block[0]);
1059 return -EINVAL;
1060 }
1061 f7_msg->count = data->block[0] + 2;
1062 for (i = 1; i < f7_msg->count; i++)
1063 f7_msg->smbus_buf[i] = data->block[i - 1];
1064 cr2 &= ~STM32F7_I2C_CR2_RD_WRN;
1065 f7_msg->read_write = I2C_SMBUS_READ;
1066 break;
1067 case I2C_SMBUS_I2C_BLOCK_DATA:
1068 /* Rely on emulated i2c transfer (through master_xfer) */
1069 return -EOPNOTSUPP;
1070 default:
1071 dev_err(dev, "Unsupported smbus protocol %d\n", f7_msg->size);
1072 return -EOPNOTSUPP;
1073 }
1074
1075 f7_msg->buf = f7_msg->smbus_buf;
1076
1077 /* Configure PEC */
1078 if ((flags & I2C_CLIENT_PEC) && f7_msg->size != I2C_SMBUS_QUICK) {
1079 cr1 |= STM32F7_I2C_CR1_PECEN;
1080 if (!f7_msg->read_write) {
1081 cr2 |= STM32F7_I2C_CR2_PECBYTE;
1082 f7_msg->count++;
1083 }
1084 } else {
1085 cr1 &= ~STM32F7_I2C_CR1_PECEN;
1086 cr2 &= ~STM32F7_I2C_CR2_PECBYTE;
1087 }
1088
1089 /* Set number of bytes to be transferred */
1090 cr2 &= ~(STM32F7_I2C_CR2_NBYTES_MASK | STM32F7_I2C_CR2_RELOAD);
1091 cr2 |= STM32F7_I2C_CR2_NBYTES(f7_msg->count);
1092
1093 /* Enable NACK, STOP, error and transfer complete interrupts */
1094 cr1 |= STM32F7_I2C_CR1_ERRIE | STM32F7_I2C_CR1_TCIE |
1095 STM32F7_I2C_CR1_STOPIE | STM32F7_I2C_CR1_NACKIE;
1096
1097 /* Clear DMA req and TX/RX interrupt */
1098 cr1 &= ~(STM32F7_I2C_CR1_RXIE | STM32F7_I2C_CR1_TXIE |
1099 STM32F7_I2C_CR1_RXDMAEN | STM32F7_I2C_CR1_TXDMAEN);
1100
1101 /* Configure DMA or enable RX/TX interrupt */
1102 i2c_dev->use_dma = false;
1103 if (i2c_dev->dma && f7_msg->count >= STM32F7_I2C_DMA_LEN_MIN) {
1104 ret = stm32_i2c_prep_dma_xfer(i2c_dev->dev, i2c_dev->dma,
1105 cr2 & STM32F7_I2C_CR2_RD_WRN,
1106 f7_msg->count, f7_msg->buf,
1107 stm32f7_i2c_dma_callback,
1108 i2c_dev);
1109 if (!ret)
1110 i2c_dev->use_dma = true;
1111 else
1112 dev_warn(i2c_dev->dev, "can't use DMA\n");
1113 }
1114
1115 if (!i2c_dev->use_dma) {
1116 if (cr2 & STM32F7_I2C_CR2_RD_WRN)
1117 cr1 |= STM32F7_I2C_CR1_RXIE;
1118 else
1119 cr1 |= STM32F7_I2C_CR1_TXIE;
1120 } else {
1121 if (cr2 & STM32F7_I2C_CR2_RD_WRN)
1122 cr1 |= STM32F7_I2C_CR1_RXDMAEN;
1123 else
1124 cr1 |= STM32F7_I2C_CR1_TXDMAEN;
1125 }
1126
1127 /* Set Start bit */
1128 cr2 |= STM32F7_I2C_CR2_START;
1129
1130 i2c_dev->master_mode = true;
1131
1132 /* Write configurations registers */
1133 writel_relaxed(cr1, base + STM32F7_I2C_CR1);
1134 writel_relaxed(cr2, base + STM32F7_I2C_CR2);
1135
1136 return 0;
1137 }
1138
stm32f7_i2c_smbus_rep_start(struct stm32f7_i2c_dev * i2c_dev)1139 static void stm32f7_i2c_smbus_rep_start(struct stm32f7_i2c_dev *i2c_dev)
1140 {
1141 struct stm32f7_i2c_msg *f7_msg = &i2c_dev->f7_msg;
1142 void __iomem *base = i2c_dev->base;
1143 u32 cr1, cr2;
1144 int ret;
1145
1146 cr2 = readl_relaxed(base + STM32F7_I2C_CR2);
1147 cr1 = readl_relaxed(base + STM32F7_I2C_CR1);
1148
1149 /* Set transfer direction */
1150 cr2 |= STM32F7_I2C_CR2_RD_WRN;
1151
1152 switch (f7_msg->size) {
1153 case I2C_SMBUS_BYTE_DATA:
1154 f7_msg->count = 1;
1155 break;
1156 case I2C_SMBUS_WORD_DATA:
1157 case I2C_SMBUS_PROC_CALL:
1158 f7_msg->count = 2;
1159 break;
1160 case I2C_SMBUS_BLOCK_DATA:
1161 case I2C_SMBUS_BLOCK_PROC_CALL:
1162 f7_msg->count = 1;
1163 cr2 |= STM32F7_I2C_CR2_RELOAD;
1164 break;
1165 }
1166
1167 f7_msg->buf = f7_msg->smbus_buf;
1168 f7_msg->stop = true;
1169
1170 /* Add one byte for PEC if needed */
1171 if (cr1 & STM32F7_I2C_CR1_PECEN) {
1172 cr2 |= STM32F7_I2C_CR2_PECBYTE;
1173 f7_msg->count++;
1174 }
1175
1176 /* Set number of bytes to be transferred */
1177 cr2 &= ~(STM32F7_I2C_CR2_NBYTES_MASK);
1178 cr2 |= STM32F7_I2C_CR2_NBYTES(f7_msg->count);
1179
1180 /*
1181 * Configure RX/TX interrupt:
1182 */
1183 cr1 &= ~(STM32F7_I2C_CR1_RXIE | STM32F7_I2C_CR1_TXIE);
1184 cr1 |= STM32F7_I2C_CR1_RXIE;
1185
1186 /*
1187 * Configure DMA or enable RX/TX interrupt:
1188 * For I2C_SMBUS_BLOCK_DATA and I2C_SMBUS_BLOCK_PROC_CALL we don't use
1189 * dma as we don't know in advance how many data will be received
1190 */
1191 cr1 &= ~(STM32F7_I2C_CR1_RXIE | STM32F7_I2C_CR1_TXIE |
1192 STM32F7_I2C_CR1_RXDMAEN | STM32F7_I2C_CR1_TXDMAEN);
1193
1194 i2c_dev->use_dma = false;
1195 if (i2c_dev->dma && f7_msg->count >= STM32F7_I2C_DMA_LEN_MIN &&
1196 f7_msg->size != I2C_SMBUS_BLOCK_DATA &&
1197 f7_msg->size != I2C_SMBUS_BLOCK_PROC_CALL) {
1198 ret = stm32_i2c_prep_dma_xfer(i2c_dev->dev, i2c_dev->dma,
1199 cr2 & STM32F7_I2C_CR2_RD_WRN,
1200 f7_msg->count, f7_msg->buf,
1201 stm32f7_i2c_dma_callback,
1202 i2c_dev);
1203
1204 if (!ret)
1205 i2c_dev->use_dma = true;
1206 else
1207 dev_warn(i2c_dev->dev, "can't use DMA\n");
1208 }
1209
1210 if (!i2c_dev->use_dma)
1211 cr1 |= STM32F7_I2C_CR1_RXIE;
1212 else
1213 cr1 |= STM32F7_I2C_CR1_RXDMAEN;
1214
1215 /* Configure Repeated Start */
1216 cr2 |= STM32F7_I2C_CR2_START;
1217
1218 /* Write configurations registers */
1219 writel_relaxed(cr1, base + STM32F7_I2C_CR1);
1220 writel_relaxed(cr2, base + STM32F7_I2C_CR2);
1221 }
1222
stm32f7_i2c_smbus_check_pec(struct stm32f7_i2c_dev * i2c_dev)1223 static int stm32f7_i2c_smbus_check_pec(struct stm32f7_i2c_dev *i2c_dev)
1224 {
1225 struct stm32f7_i2c_msg *f7_msg = &i2c_dev->f7_msg;
1226 u8 count, internal_pec, received_pec;
1227
1228 internal_pec = readl_relaxed(i2c_dev->base + STM32F7_I2C_PECR);
1229
1230 switch (f7_msg->size) {
1231 case I2C_SMBUS_BYTE:
1232 case I2C_SMBUS_BYTE_DATA:
1233 received_pec = f7_msg->smbus_buf[1];
1234 break;
1235 case I2C_SMBUS_WORD_DATA:
1236 case I2C_SMBUS_PROC_CALL:
1237 received_pec = f7_msg->smbus_buf[2];
1238 break;
1239 case I2C_SMBUS_BLOCK_DATA:
1240 case I2C_SMBUS_BLOCK_PROC_CALL:
1241 count = f7_msg->smbus_buf[0];
1242 received_pec = f7_msg->smbus_buf[count];
1243 break;
1244 default:
1245 dev_err(i2c_dev->dev, "Unsupported smbus protocol for PEC\n");
1246 return -EINVAL;
1247 }
1248
1249 if (internal_pec != received_pec) {
1250 dev_err(i2c_dev->dev, "Bad PEC 0x%02x vs. 0x%02x\n",
1251 internal_pec, received_pec);
1252 return -EBADMSG;
1253 }
1254
1255 return 0;
1256 }
1257
stm32f7_i2c_is_addr_match(struct i2c_client * slave,u32 addcode)1258 static bool stm32f7_i2c_is_addr_match(struct i2c_client *slave, u32 addcode)
1259 {
1260 u32 addr;
1261
1262 if (!slave)
1263 return false;
1264
1265 if (slave->flags & I2C_CLIENT_TEN) {
1266 /*
1267 * For 10-bit addr, addcode = 11110XY with
1268 * X = Bit 9 of slave address
1269 * Y = Bit 8 of slave address
1270 */
1271 addr = slave->addr >> 8;
1272 addr |= 0x78;
1273 if (addr == addcode)
1274 return true;
1275 } else {
1276 addr = slave->addr & 0x7f;
1277 if (addr == addcode)
1278 return true;
1279 }
1280
1281 return false;
1282 }
1283
stm32f7_i2c_slave_start(struct stm32f7_i2c_dev * i2c_dev)1284 static void stm32f7_i2c_slave_start(struct stm32f7_i2c_dev *i2c_dev)
1285 {
1286 struct i2c_client *slave = i2c_dev->slave_running;
1287 void __iomem *base = i2c_dev->base;
1288 u32 mask;
1289 u8 value = 0;
1290
1291 if (i2c_dev->slave_dir) {
1292 /* Notify i2c slave that new read transfer is starting */
1293 i2c_slave_event(slave, I2C_SLAVE_READ_REQUESTED, &value);
1294
1295 /*
1296 * Disable slave TX config in case of I2C combined message
1297 * (I2C Write followed by I2C Read)
1298 */
1299 mask = STM32F7_I2C_CR2_RELOAD;
1300 stm32f7_i2c_clr_bits(base + STM32F7_I2C_CR2, mask);
1301 mask = STM32F7_I2C_CR1_SBC | STM32F7_I2C_CR1_RXIE |
1302 STM32F7_I2C_CR1_TCIE;
1303 stm32f7_i2c_clr_bits(base + STM32F7_I2C_CR1, mask);
1304
1305 /* Enable TX empty, STOP, NACK interrupts */
1306 mask = STM32F7_I2C_CR1_STOPIE | STM32F7_I2C_CR1_NACKIE |
1307 STM32F7_I2C_CR1_TXIE;
1308 stm32f7_i2c_set_bits(base + STM32F7_I2C_CR1, mask);
1309
1310 /* Write 1st data byte */
1311 writel_relaxed(value, base + STM32F7_I2C_TXDR);
1312 } else {
1313 /* Notify i2c slave that new write transfer is starting */
1314 i2c_slave_event(slave, I2C_SLAVE_WRITE_REQUESTED, &value);
1315
1316 /* Set reload mode to be able to ACK/NACK each received byte */
1317 mask = STM32F7_I2C_CR2_RELOAD;
1318 stm32f7_i2c_set_bits(base + STM32F7_I2C_CR2, mask);
1319
1320 /*
1321 * Set STOP, NACK, RX empty and transfer complete interrupts.*
1322 * Set Slave Byte Control to be able to ACK/NACK each data
1323 * byte received
1324 */
1325 mask = STM32F7_I2C_CR1_STOPIE | STM32F7_I2C_CR1_NACKIE |
1326 STM32F7_I2C_CR1_SBC | STM32F7_I2C_CR1_RXIE |
1327 STM32F7_I2C_CR1_TCIE;
1328 stm32f7_i2c_set_bits(base + STM32F7_I2C_CR1, mask);
1329 }
1330 }
1331
stm32f7_i2c_slave_addr(struct stm32f7_i2c_dev * i2c_dev)1332 static void stm32f7_i2c_slave_addr(struct stm32f7_i2c_dev *i2c_dev)
1333 {
1334 void __iomem *base = i2c_dev->base;
1335 u32 isr, addcode, dir, mask;
1336 int i;
1337
1338 isr = readl_relaxed(i2c_dev->base + STM32F7_I2C_ISR);
1339 addcode = STM32F7_I2C_ISR_ADDCODE_GET(isr);
1340 dir = isr & STM32F7_I2C_ISR_DIR;
1341
1342 for (i = 0; i < STM32F7_I2C_MAX_SLAVE; i++) {
1343 if (stm32f7_i2c_is_addr_match(i2c_dev->slave[i], addcode)) {
1344 i2c_dev->slave_running = i2c_dev->slave[i];
1345 i2c_dev->slave_dir = dir;
1346
1347 /* Start I2C slave processing */
1348 stm32f7_i2c_slave_start(i2c_dev);
1349
1350 /* Clear ADDR flag */
1351 mask = STM32F7_I2C_ICR_ADDRCF;
1352 writel_relaxed(mask, base + STM32F7_I2C_ICR);
1353 break;
1354 }
1355 }
1356 }
1357
stm32f7_i2c_get_slave_id(struct stm32f7_i2c_dev * i2c_dev,struct i2c_client * slave,int * id)1358 static int stm32f7_i2c_get_slave_id(struct stm32f7_i2c_dev *i2c_dev,
1359 struct i2c_client *slave, int *id)
1360 {
1361 int i;
1362
1363 for (i = 0; i < STM32F7_I2C_MAX_SLAVE; i++) {
1364 if (i2c_dev->slave[i] == slave) {
1365 *id = i;
1366 return 0;
1367 }
1368 }
1369
1370 dev_err(i2c_dev->dev, "Slave 0x%x not registered\n", slave->addr);
1371
1372 return -ENODEV;
1373 }
1374
stm32f7_i2c_get_free_slave_id(struct stm32f7_i2c_dev * i2c_dev,struct i2c_client * slave,int * id)1375 static int stm32f7_i2c_get_free_slave_id(struct stm32f7_i2c_dev *i2c_dev,
1376 struct i2c_client *slave, int *id)
1377 {
1378 struct device *dev = i2c_dev->dev;
1379 int i;
1380
1381 /*
1382 * slave[STM32F7_SLAVE_HOSTNOTIFY] support only SMBus Host address (0x8)
1383 * slave[STM32F7_SLAVE_7_10_BITS_ADDR] supports 7-bit and 10-bit slave address
1384 * slave[STM32F7_SLAVE_7_BITS_ADDR] supports 7-bit slave address only
1385 */
1386 if (i2c_dev->smbus_mode && (slave->addr == 0x08)) {
1387 if (i2c_dev->slave[STM32F7_SLAVE_HOSTNOTIFY])
1388 goto fail;
1389 *id = STM32F7_SLAVE_HOSTNOTIFY;
1390 return 0;
1391 }
1392
1393 for (i = STM32F7_I2C_MAX_SLAVE - 1; i > STM32F7_SLAVE_HOSTNOTIFY; i--) {
1394 if ((i == STM32F7_SLAVE_7_BITS_ADDR) &&
1395 (slave->flags & I2C_CLIENT_TEN))
1396 continue;
1397 if (!i2c_dev->slave[i]) {
1398 *id = i;
1399 return 0;
1400 }
1401 }
1402
1403 fail:
1404 dev_err(dev, "Slave 0x%x could not be registered\n", slave->addr);
1405
1406 return -EINVAL;
1407 }
1408
stm32f7_i2c_is_slave_registered(struct stm32f7_i2c_dev * i2c_dev)1409 static bool stm32f7_i2c_is_slave_registered(struct stm32f7_i2c_dev *i2c_dev)
1410 {
1411 int i;
1412
1413 for (i = 0; i < STM32F7_I2C_MAX_SLAVE; i++) {
1414 if (i2c_dev->slave[i])
1415 return true;
1416 }
1417
1418 return false;
1419 }
1420
stm32f7_i2c_is_slave_busy(struct stm32f7_i2c_dev * i2c_dev)1421 static bool stm32f7_i2c_is_slave_busy(struct stm32f7_i2c_dev *i2c_dev)
1422 {
1423 int i, busy;
1424
1425 busy = 0;
1426 for (i = 0; i < STM32F7_I2C_MAX_SLAVE; i++) {
1427 if (i2c_dev->slave[i])
1428 busy++;
1429 }
1430
1431 return i == busy;
1432 }
1433
stm32f7_i2c_slave_isr_event(struct stm32f7_i2c_dev * i2c_dev,u32 status)1434 static irqreturn_t stm32f7_i2c_slave_isr_event(struct stm32f7_i2c_dev *i2c_dev, u32 status)
1435 {
1436 void __iomem *base = i2c_dev->base;
1437 u32 cr2, mask;
1438 u8 val;
1439 int ret;
1440
1441 /* Slave transmitter mode */
1442 if (status & STM32F7_I2C_ISR_TXIS) {
1443 i2c_slave_event(i2c_dev->slave_running,
1444 I2C_SLAVE_READ_PROCESSED,
1445 &val);
1446
1447 /* Write data byte */
1448 writel_relaxed(val, base + STM32F7_I2C_TXDR);
1449 }
1450
1451 /* Transfer Complete Reload for Slave receiver mode */
1452 if (status & STM32F7_I2C_ISR_TCR || status & STM32F7_I2C_ISR_RXNE) {
1453 /*
1454 * Read data byte then set NBYTES to receive next byte or NACK
1455 * the current received byte
1456 */
1457 val = readb_relaxed(i2c_dev->base + STM32F7_I2C_RXDR);
1458 ret = i2c_slave_event(i2c_dev->slave_running,
1459 I2C_SLAVE_WRITE_RECEIVED,
1460 &val);
1461 if (!ret) {
1462 cr2 = readl_relaxed(i2c_dev->base + STM32F7_I2C_CR2);
1463 cr2 |= STM32F7_I2C_CR2_NBYTES(1);
1464 writel_relaxed(cr2, i2c_dev->base + STM32F7_I2C_CR2);
1465 } else {
1466 mask = STM32F7_I2C_CR2_NACK;
1467 stm32f7_i2c_set_bits(base + STM32F7_I2C_CR2, mask);
1468 }
1469 }
1470
1471 /* NACK received */
1472 if (status & STM32F7_I2C_ISR_NACKF) {
1473 dev_dbg(i2c_dev->dev, "<%s>: Receive NACK\n", __func__);
1474 writel_relaxed(STM32F7_I2C_ICR_NACKCF, base + STM32F7_I2C_ICR);
1475 }
1476
1477 /* STOP received */
1478 if (status & STM32F7_I2C_ISR_STOPF) {
1479 /* Disable interrupts */
1480 stm32f7_i2c_disable_irq(i2c_dev, STM32F7_I2C_XFER_IRQ_MASK);
1481
1482 if (i2c_dev->slave_dir) {
1483 /*
1484 * Flush TX buffer in order to not used the byte in
1485 * TXDR for the next transfer
1486 */
1487 mask = STM32F7_I2C_ISR_TXE;
1488 stm32f7_i2c_set_bits(base + STM32F7_I2C_ISR, mask);
1489 }
1490
1491 /* Clear STOP flag */
1492 writel_relaxed(STM32F7_I2C_ICR_STOPCF, base + STM32F7_I2C_ICR);
1493
1494 /* Notify i2c slave that a STOP flag has been detected */
1495 i2c_slave_event(i2c_dev->slave_running, I2C_SLAVE_STOP, &val);
1496
1497 i2c_dev->slave_running = NULL;
1498 }
1499
1500 /* Address match received */
1501 if (status & STM32F7_I2C_ISR_ADDR)
1502 stm32f7_i2c_slave_addr(i2c_dev);
1503
1504 return IRQ_HANDLED;
1505 }
1506
stm32f7_i2c_handle_isr_errs(struct stm32f7_i2c_dev * i2c_dev,u32 status)1507 static irqreturn_t stm32f7_i2c_handle_isr_errs(struct stm32f7_i2c_dev *i2c_dev, u32 status)
1508 {
1509 struct stm32f7_i2c_msg *f7_msg = &i2c_dev->f7_msg;
1510 u16 addr = f7_msg->addr;
1511 void __iomem *base = i2c_dev->base;
1512 struct device *dev = i2c_dev->dev;
1513 struct stm32_i2c_dma *dma = i2c_dev->dma;
1514
1515 /* Bus error */
1516 if (status & STM32F7_I2C_ISR_BERR) {
1517 dev_err(dev, "Bus error accessing addr 0x%x\n", addr);
1518 writel_relaxed(STM32F7_I2C_ICR_BERRCF, base + STM32F7_I2C_ICR);
1519 stm32f7_i2c_release_bus(&i2c_dev->adap);
1520 f7_msg->result = -EIO;
1521 }
1522
1523 /* Arbitration loss */
1524 if (status & STM32F7_I2C_ISR_ARLO) {
1525 dev_dbg(dev, "Arbitration loss accessing addr 0x%x\n", addr);
1526 writel_relaxed(STM32F7_I2C_ICR_ARLOCF, base + STM32F7_I2C_ICR);
1527 f7_msg->result = -EAGAIN;
1528 }
1529
1530 if (status & STM32F7_I2C_ISR_PECERR) {
1531 dev_err(dev, "PEC error in reception accessing addr 0x%x\n", addr);
1532 writel_relaxed(STM32F7_I2C_ICR_PECCF, base + STM32F7_I2C_ICR);
1533 f7_msg->result = -EINVAL;
1534 }
1535
1536 if (status & STM32F7_I2C_ISR_ALERT) {
1537 dev_dbg(dev, "SMBus alert received\n");
1538 writel_relaxed(STM32F7_I2C_ICR_ALERTCF, base + STM32F7_I2C_ICR);
1539 i2c_handle_smbus_alert(i2c_dev->alert->ara);
1540 return IRQ_HANDLED;
1541 }
1542
1543 if (!i2c_dev->slave_running) {
1544 u32 mask;
1545 /* Disable interrupts */
1546 if (stm32f7_i2c_is_slave_registered(i2c_dev))
1547 mask = STM32F7_I2C_XFER_IRQ_MASK;
1548 else
1549 mask = STM32F7_I2C_ALL_IRQ_MASK;
1550 stm32f7_i2c_disable_irq(i2c_dev, mask);
1551 }
1552
1553 /* Disable dma */
1554 if (i2c_dev->use_dma) {
1555 stm32f7_i2c_disable_dma_req(i2c_dev);
1556 dmaengine_terminate_async(dma->chan_using);
1557 }
1558
1559 i2c_dev->master_mode = false;
1560 complete(&i2c_dev->complete);
1561
1562 return IRQ_HANDLED;
1563 }
1564
1565 #define STM32F7_ERR_EVENTS (STM32F7_I2C_ISR_BERR | STM32F7_I2C_ISR_ARLO |\
1566 STM32F7_I2C_ISR_PECERR | STM32F7_I2C_ISR_ALERT)
stm32f7_i2c_isr_event(int irq,void * data)1567 static irqreturn_t stm32f7_i2c_isr_event(int irq, void *data)
1568 {
1569 struct stm32f7_i2c_dev *i2c_dev = data;
1570 u32 status;
1571
1572 status = readl_relaxed(i2c_dev->base + STM32F7_I2C_ISR);
1573
1574 /*
1575 * Check if the interrupt is for a slave device or related
1576 * to errors flags (in case of single it line mode)
1577 */
1578 if (!i2c_dev->master_mode ||
1579 (i2c_dev->setup.single_it_line && (status & STM32F7_ERR_EVENTS)))
1580 return IRQ_WAKE_THREAD;
1581
1582 /* Tx empty */
1583 if (status & STM32F7_I2C_ISR_TXIS)
1584 stm32f7_i2c_write_tx_data(i2c_dev);
1585
1586 /* RX not empty */
1587 if (status & STM32F7_I2C_ISR_RXNE)
1588 stm32f7_i2c_read_rx_data(i2c_dev);
1589
1590 /* Wake up the thread if other flags are raised */
1591 if (status &
1592 (STM32F7_I2C_ISR_NACKF | STM32F7_I2C_ISR_STOPF |
1593 STM32F7_I2C_ISR_TC | STM32F7_I2C_ISR_TCR))
1594 return IRQ_WAKE_THREAD;
1595
1596 return IRQ_HANDLED;
1597 }
1598
stm32f7_i2c_isr_event_thread(int irq,void * data)1599 static irqreturn_t stm32f7_i2c_isr_event_thread(int irq, void *data)
1600 {
1601 struct stm32f7_i2c_dev *i2c_dev = data;
1602 struct stm32f7_i2c_msg *f7_msg = &i2c_dev->f7_msg;
1603 struct stm32_i2c_dma *dma = i2c_dev->dma;
1604 void __iomem *base = i2c_dev->base;
1605 u32 status, mask;
1606 int ret;
1607
1608 status = readl_relaxed(i2c_dev->base + STM32F7_I2C_ISR);
1609
1610 if (!i2c_dev->master_mode)
1611 return stm32f7_i2c_slave_isr_event(i2c_dev, status);
1612
1613 /* Handle errors in case of this handler is used for events/errors */
1614 if (i2c_dev->setup.single_it_line && (status & STM32F7_ERR_EVENTS))
1615 return stm32f7_i2c_handle_isr_errs(i2c_dev, status);
1616
1617 /* NACK received */
1618 if (status & STM32F7_I2C_ISR_NACKF) {
1619 dev_dbg(i2c_dev->dev, "<%s>: Receive NACK (addr %x)\n",
1620 __func__, f7_msg->addr);
1621 writel_relaxed(STM32F7_I2C_ICR_NACKCF, base + STM32F7_I2C_ICR);
1622 if (i2c_dev->use_dma) {
1623 stm32f7_i2c_disable_dma_req(i2c_dev);
1624 dmaengine_terminate_async(dma->chan_using);
1625 }
1626 f7_msg->result = -ENXIO;
1627 }
1628
1629 if (status & STM32F7_I2C_ISR_TCR) {
1630 if (f7_msg->smbus)
1631 stm32f7_i2c_smbus_reload(i2c_dev);
1632 else
1633 stm32f7_i2c_reload(i2c_dev);
1634 }
1635
1636 /* Transfer complete */
1637 if (status & STM32F7_I2C_ISR_TC) {
1638 /* Wait for dma transfer completion before sending next message */
1639 if (i2c_dev->use_dma && !f7_msg->result) {
1640 ret = wait_for_completion_timeout(&i2c_dev->dma->dma_complete, HZ);
1641 if (!ret) {
1642 dev_dbg(i2c_dev->dev, "<%s>: Timed out\n", __func__);
1643 stm32f7_i2c_disable_dma_req(i2c_dev);
1644 dmaengine_terminate_async(dma->chan_using);
1645 f7_msg->result = -ETIMEDOUT;
1646 }
1647 }
1648 if (f7_msg->stop) {
1649 mask = STM32F7_I2C_CR2_STOP;
1650 stm32f7_i2c_set_bits(base + STM32F7_I2C_CR2, mask);
1651 } else if (f7_msg->smbus) {
1652 stm32f7_i2c_smbus_rep_start(i2c_dev);
1653 } else {
1654 i2c_dev->msg_id++;
1655 i2c_dev->msg++;
1656 stm32f7_i2c_xfer_msg(i2c_dev, i2c_dev->msg);
1657 }
1658 }
1659
1660 /* STOP detection flag */
1661 if (status & STM32F7_I2C_ISR_STOPF) {
1662 /* Disable interrupts */
1663 if (stm32f7_i2c_is_slave_registered(i2c_dev))
1664 mask = STM32F7_I2C_XFER_IRQ_MASK;
1665 else
1666 mask = STM32F7_I2C_ALL_IRQ_MASK;
1667 stm32f7_i2c_disable_irq(i2c_dev, mask);
1668
1669 /* Clear STOP flag */
1670 writel_relaxed(STM32F7_I2C_ICR_STOPCF, base + STM32F7_I2C_ICR);
1671
1672 i2c_dev->master_mode = false;
1673 complete(&i2c_dev->complete);
1674 }
1675
1676 return IRQ_HANDLED;
1677 }
1678
stm32f7_i2c_isr_error_thread(int irq,void * data)1679 static irqreturn_t stm32f7_i2c_isr_error_thread(int irq, void *data)
1680 {
1681 struct stm32f7_i2c_dev *i2c_dev = data;
1682 u32 status;
1683
1684 status = readl_relaxed(i2c_dev->base + STM32F7_I2C_ISR);
1685
1686 return stm32f7_i2c_handle_isr_errs(i2c_dev, status);
1687 }
1688
stm32f7_i2c_wait_polling(struct stm32f7_i2c_dev * i2c_dev)1689 static int stm32f7_i2c_wait_polling(struct stm32f7_i2c_dev *i2c_dev)
1690 {
1691 ktime_t timeout = ktime_add_ms(ktime_get(), i2c_dev->adap.timeout);
1692
1693 while (ktime_compare(ktime_get(), timeout) < 0) {
1694 udelay(5);
1695 stm32f7_i2c_isr_event(0, i2c_dev);
1696
1697 if (completion_done(&i2c_dev->complete))
1698 return 1;
1699 }
1700
1701 return 0;
1702 }
1703
stm32f7_i2c_xfer_core(struct i2c_adapter * i2c_adap,struct i2c_msg msgs[],int num)1704 static int stm32f7_i2c_xfer_core(struct i2c_adapter *i2c_adap,
1705 struct i2c_msg msgs[], int num)
1706 {
1707 struct stm32f7_i2c_dev *i2c_dev = i2c_get_adapdata(i2c_adap);
1708 struct stm32f7_i2c_msg *f7_msg = &i2c_dev->f7_msg;
1709 struct stm32_i2c_dma *dma = i2c_dev->dma;
1710 unsigned long time_left;
1711 int ret;
1712
1713 i2c_dev->msg = msgs;
1714 i2c_dev->msg_num = num;
1715 i2c_dev->msg_id = 0;
1716 f7_msg->smbus = false;
1717
1718 ret = pm_runtime_resume_and_get(i2c_dev->dev);
1719 if (ret < 0)
1720 return ret;
1721
1722 ret = stm32f7_i2c_wait_free_bus(i2c_dev);
1723 if (ret)
1724 goto pm_free;
1725
1726 stm32f7_i2c_xfer_msg(i2c_dev, msgs);
1727
1728 if (!i2c_dev->atomic)
1729 time_left = wait_for_completion_timeout(&i2c_dev->complete,
1730 i2c_dev->adap.timeout);
1731 else
1732 time_left = stm32f7_i2c_wait_polling(i2c_dev);
1733
1734 ret = f7_msg->result;
1735 if (ret) {
1736 if (i2c_dev->use_dma)
1737 dmaengine_synchronize(dma->chan_using);
1738
1739 /*
1740 * It is possible that some unsent data have already been
1741 * written into TXDR. To avoid sending old data in a
1742 * further transfer, flush TXDR in case of any error
1743 */
1744 writel_relaxed(STM32F7_I2C_ISR_TXE,
1745 i2c_dev->base + STM32F7_I2C_ISR);
1746 goto pm_free;
1747 }
1748
1749 if (!time_left) {
1750 dev_dbg(i2c_dev->dev, "Access to slave 0x%x timed out\n",
1751 i2c_dev->msg->addr);
1752 if (i2c_dev->use_dma)
1753 dmaengine_terminate_sync(dma->chan_using);
1754 stm32f7_i2c_wait_free_bus(i2c_dev);
1755 ret = -ETIMEDOUT;
1756 }
1757
1758 pm_free:
1759 pm_runtime_mark_last_busy(i2c_dev->dev);
1760 pm_runtime_put_autosuspend(i2c_dev->dev);
1761
1762 return (ret < 0) ? ret : num;
1763 }
1764
stm32f7_i2c_xfer(struct i2c_adapter * i2c_adap,struct i2c_msg msgs[],int num)1765 static int stm32f7_i2c_xfer(struct i2c_adapter *i2c_adap,
1766 struct i2c_msg msgs[], int num)
1767 {
1768 struct stm32f7_i2c_dev *i2c_dev = i2c_get_adapdata(i2c_adap);
1769
1770 i2c_dev->atomic = false;
1771 return stm32f7_i2c_xfer_core(i2c_adap, msgs, num);
1772 }
1773
stm32f7_i2c_xfer_atomic(struct i2c_adapter * i2c_adap,struct i2c_msg msgs[],int num)1774 static int stm32f7_i2c_xfer_atomic(struct i2c_adapter *i2c_adap,
1775 struct i2c_msg msgs[], int num)
1776 {
1777 struct stm32f7_i2c_dev *i2c_dev = i2c_get_adapdata(i2c_adap);
1778
1779 i2c_dev->atomic = true;
1780 return stm32f7_i2c_xfer_core(i2c_adap, msgs, num);
1781 }
1782
stm32f7_i2c_smbus_xfer(struct i2c_adapter * adapter,u16 addr,unsigned short flags,char read_write,u8 command,int size,union i2c_smbus_data * data)1783 static int stm32f7_i2c_smbus_xfer(struct i2c_adapter *adapter, u16 addr,
1784 unsigned short flags, char read_write,
1785 u8 command, int size,
1786 union i2c_smbus_data *data)
1787 {
1788 struct stm32f7_i2c_dev *i2c_dev = i2c_get_adapdata(adapter);
1789 struct stm32f7_i2c_msg *f7_msg = &i2c_dev->f7_msg;
1790 struct stm32_i2c_dma *dma = i2c_dev->dma;
1791 struct device *dev = i2c_dev->dev;
1792 unsigned long time_left;
1793 int i, ret;
1794
1795 f7_msg->addr = addr;
1796 f7_msg->size = size;
1797 f7_msg->read_write = read_write;
1798 f7_msg->smbus = true;
1799
1800 ret = pm_runtime_resume_and_get(dev);
1801 if (ret < 0)
1802 return ret;
1803
1804 ret = stm32f7_i2c_wait_free_bus(i2c_dev);
1805 if (ret)
1806 goto pm_free;
1807
1808 ret = stm32f7_i2c_smbus_xfer_msg(i2c_dev, flags, command, data);
1809 if (ret)
1810 goto pm_free;
1811
1812 time_left = wait_for_completion_timeout(&i2c_dev->complete,
1813 i2c_dev->adap.timeout);
1814 ret = f7_msg->result;
1815 if (ret) {
1816 if (i2c_dev->use_dma)
1817 dmaengine_synchronize(dma->chan_using);
1818
1819 /*
1820 * It is possible that some unsent data have already been
1821 * written into TXDR. To avoid sending old data in a
1822 * further transfer, flush TXDR in case of any error
1823 */
1824 writel_relaxed(STM32F7_I2C_ISR_TXE,
1825 i2c_dev->base + STM32F7_I2C_ISR);
1826 goto pm_free;
1827 }
1828
1829 if (!time_left) {
1830 dev_dbg(dev, "Access to slave 0x%x timed out\n", f7_msg->addr);
1831 if (i2c_dev->use_dma)
1832 dmaengine_terminate_sync(dma->chan_using);
1833 stm32f7_i2c_wait_free_bus(i2c_dev);
1834 ret = -ETIMEDOUT;
1835 goto pm_free;
1836 }
1837
1838 /* Check PEC */
1839 if ((flags & I2C_CLIENT_PEC) && size != I2C_SMBUS_QUICK && read_write) {
1840 ret = stm32f7_i2c_smbus_check_pec(i2c_dev);
1841 if (ret)
1842 goto pm_free;
1843 }
1844
1845 if (read_write && size != I2C_SMBUS_QUICK) {
1846 switch (size) {
1847 case I2C_SMBUS_BYTE:
1848 case I2C_SMBUS_BYTE_DATA:
1849 data->byte = f7_msg->smbus_buf[0];
1850 break;
1851 case I2C_SMBUS_WORD_DATA:
1852 case I2C_SMBUS_PROC_CALL:
1853 data->word = f7_msg->smbus_buf[0] |
1854 (f7_msg->smbus_buf[1] << 8);
1855 break;
1856 case I2C_SMBUS_BLOCK_DATA:
1857 case I2C_SMBUS_BLOCK_PROC_CALL:
1858 for (i = 0; i <= f7_msg->smbus_buf[0]; i++)
1859 data->block[i] = f7_msg->smbus_buf[i];
1860 break;
1861 default:
1862 dev_err(dev, "Unsupported smbus transaction\n");
1863 ret = -EINVAL;
1864 }
1865 }
1866
1867 pm_free:
1868 pm_runtime_mark_last_busy(dev);
1869 pm_runtime_put_autosuspend(dev);
1870 return ret;
1871 }
1872
stm32f7_i2c_enable_wakeup(struct stm32f7_i2c_dev * i2c_dev,bool enable)1873 static void stm32f7_i2c_enable_wakeup(struct stm32f7_i2c_dev *i2c_dev,
1874 bool enable)
1875 {
1876 void __iomem *base = i2c_dev->base;
1877 u32 mask = STM32F7_I2C_CR1_WUPEN;
1878
1879 if (!i2c_dev->wakeup_src)
1880 return;
1881
1882 if (enable) {
1883 device_set_wakeup_enable(i2c_dev->dev, true);
1884 stm32f7_i2c_set_bits(base + STM32F7_I2C_CR1, mask);
1885 } else {
1886 device_set_wakeup_enable(i2c_dev->dev, false);
1887 stm32f7_i2c_clr_bits(base + STM32F7_I2C_CR1, mask);
1888 }
1889 }
1890
stm32f7_i2c_reg_slave(struct i2c_client * slave)1891 static int stm32f7_i2c_reg_slave(struct i2c_client *slave)
1892 {
1893 struct stm32f7_i2c_dev *i2c_dev = i2c_get_adapdata(slave->adapter);
1894 void __iomem *base = i2c_dev->base;
1895 struct device *dev = i2c_dev->dev;
1896 u32 oar1, oar2, mask;
1897 int id, ret;
1898
1899 if (slave->flags & I2C_CLIENT_PEC) {
1900 dev_err(dev, "SMBus PEC not supported in slave mode\n");
1901 return -EINVAL;
1902 }
1903
1904 if (stm32f7_i2c_is_slave_busy(i2c_dev)) {
1905 dev_err(dev, "Too much slave registered\n");
1906 return -EBUSY;
1907 }
1908
1909 ret = stm32f7_i2c_get_free_slave_id(i2c_dev, slave, &id);
1910 if (ret)
1911 return ret;
1912
1913 ret = pm_runtime_resume_and_get(dev);
1914 if (ret < 0)
1915 return ret;
1916
1917 if (!stm32f7_i2c_is_slave_registered(i2c_dev))
1918 stm32f7_i2c_enable_wakeup(i2c_dev, true);
1919
1920 switch (id) {
1921 case 0:
1922 /* Slave SMBus Host */
1923 i2c_dev->slave[id] = slave;
1924 break;
1925
1926 case 1:
1927 /* Configure Own Address 1 */
1928 oar1 = readl_relaxed(i2c_dev->base + STM32F7_I2C_OAR1);
1929 oar1 &= ~STM32F7_I2C_OAR1_MASK;
1930 if (slave->flags & I2C_CLIENT_TEN) {
1931 oar1 |= STM32F7_I2C_OAR1_OA1_10(slave->addr);
1932 oar1 |= STM32F7_I2C_OAR1_OA1MODE;
1933 } else {
1934 oar1 |= STM32F7_I2C_OAR1_OA1_7(slave->addr);
1935 }
1936 oar1 |= STM32F7_I2C_OAR1_OA1EN;
1937 i2c_dev->slave[id] = slave;
1938 writel_relaxed(oar1, i2c_dev->base + STM32F7_I2C_OAR1);
1939 break;
1940
1941 case 2:
1942 /* Configure Own Address 2 */
1943 oar2 = readl_relaxed(i2c_dev->base + STM32F7_I2C_OAR2);
1944 oar2 &= ~STM32F7_I2C_OAR2_MASK;
1945 if (slave->flags & I2C_CLIENT_TEN) {
1946 ret = -EOPNOTSUPP;
1947 goto pm_free;
1948 }
1949
1950 oar2 |= STM32F7_I2C_OAR2_OA2_7(slave->addr);
1951 oar2 |= STM32F7_I2C_OAR2_OA2EN;
1952 i2c_dev->slave[id] = slave;
1953 writel_relaxed(oar2, i2c_dev->base + STM32F7_I2C_OAR2);
1954 break;
1955
1956 default:
1957 dev_err(dev, "I2C slave id not supported\n");
1958 ret = -ENODEV;
1959 goto pm_free;
1960 }
1961
1962 /* Enable ACK */
1963 stm32f7_i2c_clr_bits(base + STM32F7_I2C_CR2, STM32F7_I2C_CR2_NACK);
1964
1965 /* Enable Address match interrupt, error interrupt and enable I2C */
1966 mask = STM32F7_I2C_CR1_ADDRIE | STM32F7_I2C_CR1_ERRIE |
1967 STM32F7_I2C_CR1_PE;
1968 stm32f7_i2c_set_bits(base + STM32F7_I2C_CR1, mask);
1969
1970 ret = 0;
1971 pm_free:
1972 if (!stm32f7_i2c_is_slave_registered(i2c_dev))
1973 stm32f7_i2c_enable_wakeup(i2c_dev, false);
1974
1975 pm_runtime_mark_last_busy(dev);
1976 pm_runtime_put_autosuspend(dev);
1977
1978 return ret;
1979 }
1980
stm32f7_i2c_unreg_slave(struct i2c_client * slave)1981 static int stm32f7_i2c_unreg_slave(struct i2c_client *slave)
1982 {
1983 struct stm32f7_i2c_dev *i2c_dev = i2c_get_adapdata(slave->adapter);
1984 void __iomem *base = i2c_dev->base;
1985 u32 mask;
1986 int id, ret;
1987
1988 ret = stm32f7_i2c_get_slave_id(i2c_dev, slave, &id);
1989 if (ret)
1990 return ret;
1991
1992 WARN_ON(!i2c_dev->slave[id]);
1993
1994 ret = pm_runtime_resume_and_get(i2c_dev->dev);
1995 if (ret < 0)
1996 return ret;
1997
1998 if (id == 1) {
1999 mask = STM32F7_I2C_OAR1_OA1EN;
2000 stm32f7_i2c_clr_bits(base + STM32F7_I2C_OAR1, mask);
2001 } else if (id == 2) {
2002 mask = STM32F7_I2C_OAR2_OA2EN;
2003 stm32f7_i2c_clr_bits(base + STM32F7_I2C_OAR2, mask);
2004 }
2005
2006 i2c_dev->slave[id] = NULL;
2007
2008 if (!stm32f7_i2c_is_slave_registered(i2c_dev)) {
2009 stm32f7_i2c_disable_irq(i2c_dev, STM32F7_I2C_ALL_IRQ_MASK);
2010 stm32f7_i2c_enable_wakeup(i2c_dev, false);
2011 }
2012
2013 pm_runtime_mark_last_busy(i2c_dev->dev);
2014 pm_runtime_put_autosuspend(i2c_dev->dev);
2015
2016 return 0;
2017 }
2018
stm32f7_i2c_write_fm_plus_bits(struct stm32f7_i2c_dev * i2c_dev,bool enable)2019 static int stm32f7_i2c_write_fm_plus_bits(struct stm32f7_i2c_dev *i2c_dev,
2020 bool enable)
2021 {
2022 int ret = 0;
2023
2024 if (i2c_dev->bus_rate <= I2C_MAX_FAST_MODE_FREQ ||
2025 (!i2c_dev->setup.fmp_cr1_bit && IS_ERR_OR_NULL(i2c_dev->regmap)))
2026 /* Optional */
2027 return 0;
2028
2029 if (i2c_dev->setup.fmp_cr1_bit) {
2030 if (enable)
2031 stm32f7_i2c_set_bits(i2c_dev->base + STM32F7_I2C_CR1, STM32_I2C_CR1_FMP);
2032 else
2033 stm32f7_i2c_clr_bits(i2c_dev->base + STM32F7_I2C_CR1, STM32_I2C_CR1_FMP);
2034 } else {
2035 if (i2c_dev->fmp_sreg == i2c_dev->fmp_creg)
2036 ret = regmap_update_bits(i2c_dev->regmap, i2c_dev->fmp_sreg,
2037 i2c_dev->fmp_mask, enable ? i2c_dev->fmp_mask : 0);
2038 else
2039 ret = regmap_write(i2c_dev->regmap,
2040 enable ? i2c_dev->fmp_sreg : i2c_dev->fmp_creg,
2041 i2c_dev->fmp_mask);
2042 }
2043
2044 return ret;
2045 }
2046
stm32f7_i2c_setup_fm_plus_bits(struct platform_device * pdev,struct stm32f7_i2c_dev * i2c_dev)2047 static int stm32f7_i2c_setup_fm_plus_bits(struct platform_device *pdev,
2048 struct stm32f7_i2c_dev *i2c_dev)
2049 {
2050 struct device_node *np = pdev->dev.of_node;
2051 int ret;
2052
2053 i2c_dev->regmap = syscon_regmap_lookup_by_phandle(np, "st,syscfg-fmp");
2054 if (IS_ERR(i2c_dev->regmap))
2055 /* Optional */
2056 return 0;
2057
2058 ret = of_property_read_u32_index(np, "st,syscfg-fmp", 1,
2059 &i2c_dev->fmp_sreg);
2060 if (ret)
2061 return ret;
2062
2063 i2c_dev->fmp_creg = i2c_dev->fmp_sreg +
2064 i2c_dev->setup.fmp_clr_offset;
2065
2066 return of_property_read_u32_index(np, "st,syscfg-fmp", 2,
2067 &i2c_dev->fmp_mask);
2068 }
2069
stm32f7_i2c_enable_smbus_host(struct stm32f7_i2c_dev * i2c_dev)2070 static int stm32f7_i2c_enable_smbus_host(struct stm32f7_i2c_dev *i2c_dev)
2071 {
2072 struct i2c_adapter *adap = &i2c_dev->adap;
2073 void __iomem *base = i2c_dev->base;
2074 struct i2c_client *client;
2075
2076 client = i2c_new_slave_host_notify_device(adap);
2077 if (IS_ERR(client))
2078 return PTR_ERR(client);
2079
2080 i2c_dev->host_notify_client = client;
2081
2082 /* Enable SMBus Host address */
2083 stm32f7_i2c_set_bits(base + STM32F7_I2C_CR1, STM32F7_I2C_CR1_SMBHEN);
2084
2085 return 0;
2086 }
2087
stm32f7_i2c_disable_smbus_host(struct stm32f7_i2c_dev * i2c_dev)2088 static void stm32f7_i2c_disable_smbus_host(struct stm32f7_i2c_dev *i2c_dev)
2089 {
2090 void __iomem *base = i2c_dev->base;
2091
2092 if (i2c_dev->host_notify_client) {
2093 /* Disable SMBus Host address */
2094 stm32f7_i2c_clr_bits(base + STM32F7_I2C_CR1,
2095 STM32F7_I2C_CR1_SMBHEN);
2096 i2c_free_slave_host_notify_device(i2c_dev->host_notify_client);
2097 }
2098 }
2099
stm32f7_i2c_enable_smbus_alert(struct stm32f7_i2c_dev * i2c_dev)2100 static int stm32f7_i2c_enable_smbus_alert(struct stm32f7_i2c_dev *i2c_dev)
2101 {
2102 struct stm32f7_i2c_alert *alert;
2103 struct i2c_adapter *adap = &i2c_dev->adap;
2104 struct device *dev = i2c_dev->dev;
2105 void __iomem *base = i2c_dev->base;
2106
2107 alert = devm_kzalloc(dev, sizeof(*alert), GFP_KERNEL);
2108 if (!alert)
2109 return -ENOMEM;
2110
2111 alert->ara = i2c_new_smbus_alert_device(adap, &alert->setup);
2112 if (IS_ERR(alert->ara))
2113 return PTR_ERR(alert->ara);
2114
2115 i2c_dev->alert = alert;
2116
2117 /* Enable SMBus Alert */
2118 stm32f7_i2c_set_bits(base + STM32F7_I2C_CR1, STM32F7_I2C_CR1_ALERTEN);
2119
2120 return 0;
2121 }
2122
stm32f7_i2c_disable_smbus_alert(struct stm32f7_i2c_dev * i2c_dev)2123 static void stm32f7_i2c_disable_smbus_alert(struct stm32f7_i2c_dev *i2c_dev)
2124 {
2125 struct stm32f7_i2c_alert *alert = i2c_dev->alert;
2126 void __iomem *base = i2c_dev->base;
2127
2128 if (alert) {
2129 /* Disable SMBus Alert */
2130 stm32f7_i2c_clr_bits(base + STM32F7_I2C_CR1,
2131 STM32F7_I2C_CR1_ALERTEN);
2132 i2c_unregister_device(alert->ara);
2133 }
2134 }
2135
stm32f7_i2c_func(struct i2c_adapter * adap)2136 static u32 stm32f7_i2c_func(struct i2c_adapter *adap)
2137 {
2138 struct stm32f7_i2c_dev *i2c_dev = i2c_get_adapdata(adap);
2139
2140 u32 func = I2C_FUNC_I2C | I2C_FUNC_10BIT_ADDR | I2C_FUNC_SLAVE |
2141 I2C_FUNC_SMBUS_QUICK | I2C_FUNC_SMBUS_BYTE |
2142 I2C_FUNC_SMBUS_BYTE_DATA | I2C_FUNC_SMBUS_WORD_DATA |
2143 I2C_FUNC_SMBUS_BLOCK_DATA | I2C_FUNC_SMBUS_BLOCK_PROC_CALL |
2144 I2C_FUNC_SMBUS_PROC_CALL | I2C_FUNC_SMBUS_PEC |
2145 I2C_FUNC_SMBUS_I2C_BLOCK;
2146
2147 if (i2c_dev->smbus_mode)
2148 func |= I2C_FUNC_SMBUS_HOST_NOTIFY;
2149
2150 return func;
2151 }
2152
2153 static const struct i2c_algorithm stm32f7_i2c_algo = {
2154 .master_xfer = stm32f7_i2c_xfer,
2155 .master_xfer_atomic = stm32f7_i2c_xfer_atomic,
2156 .smbus_xfer = stm32f7_i2c_smbus_xfer,
2157 .functionality = stm32f7_i2c_func,
2158 .reg_slave = stm32f7_i2c_reg_slave,
2159 .unreg_slave = stm32f7_i2c_unreg_slave,
2160 };
2161
stm32f7_i2c_probe(struct platform_device * pdev)2162 static int stm32f7_i2c_probe(struct platform_device *pdev)
2163 {
2164 struct stm32f7_i2c_dev *i2c_dev;
2165 const struct stm32f7_i2c_setup *setup;
2166 struct resource *res;
2167 struct i2c_adapter *adap;
2168 struct reset_control *rst;
2169 dma_addr_t phy_addr;
2170 int irq_error, irq_event, ret;
2171
2172 i2c_dev = devm_kzalloc(&pdev->dev, sizeof(*i2c_dev), GFP_KERNEL);
2173 if (!i2c_dev)
2174 return -ENOMEM;
2175
2176 setup = of_device_get_match_data(&pdev->dev);
2177 if (!setup) {
2178 dev_err(&pdev->dev, "Can't get device data\n");
2179 return -ENODEV;
2180 }
2181 i2c_dev->setup = *setup;
2182
2183 i2c_dev->base = devm_platform_get_and_ioremap_resource(pdev, 0, &res);
2184 if (IS_ERR(i2c_dev->base))
2185 return PTR_ERR(i2c_dev->base);
2186 phy_addr = (dma_addr_t)res->start;
2187
2188 irq_event = platform_get_irq(pdev, 0);
2189 if (irq_event < 0)
2190 return irq_event;
2191
2192 i2c_dev->wakeup_src = of_property_read_bool(pdev->dev.of_node,
2193 "wakeup-source");
2194
2195 i2c_dev->clk = devm_clk_get_enabled(&pdev->dev, NULL);
2196 if (IS_ERR(i2c_dev->clk))
2197 return dev_err_probe(&pdev->dev, PTR_ERR(i2c_dev->clk),
2198 "Failed to enable controller clock\n");
2199
2200 rst = devm_reset_control_get(&pdev->dev, NULL);
2201 if (IS_ERR(rst))
2202 return dev_err_probe(&pdev->dev, PTR_ERR(rst),
2203 "Error: Missing reset ctrl\n");
2204
2205 reset_control_assert(rst);
2206 udelay(2);
2207 reset_control_deassert(rst);
2208
2209 i2c_dev->dev = &pdev->dev;
2210
2211 ret = devm_request_threaded_irq(&pdev->dev, irq_event,
2212 stm32f7_i2c_isr_event,
2213 stm32f7_i2c_isr_event_thread,
2214 IRQF_ONESHOT,
2215 pdev->name, i2c_dev);
2216 if (ret)
2217 return dev_err_probe(&pdev->dev, ret, "Failed to request irq event\n");
2218
2219 if (!i2c_dev->setup.single_it_line) {
2220 irq_error = platform_get_irq(pdev, 1);
2221 if (irq_error < 0)
2222 return irq_error;
2223
2224 ret = devm_request_threaded_irq(&pdev->dev, irq_error,
2225 NULL,
2226 stm32f7_i2c_isr_error_thread,
2227 IRQF_ONESHOT,
2228 pdev->name, i2c_dev);
2229 if (ret)
2230 return dev_err_probe(&pdev->dev, ret, "Failed to request irq error\n");
2231 }
2232
2233 ret = stm32f7_i2c_setup_timing(i2c_dev, &i2c_dev->setup);
2234 if (ret)
2235 return ret;
2236
2237 /* Setup Fast mode plus if necessary */
2238 if (i2c_dev->bus_rate > I2C_MAX_FAST_MODE_FREQ) {
2239 if (!i2c_dev->setup.fmp_cr1_bit) {
2240 ret = stm32f7_i2c_setup_fm_plus_bits(pdev, i2c_dev);
2241 if (ret)
2242 return ret;
2243 }
2244
2245 ret = stm32f7_i2c_write_fm_plus_bits(i2c_dev, true);
2246 if (ret)
2247 return ret;
2248 }
2249
2250 adap = &i2c_dev->adap;
2251 i2c_set_adapdata(adap, i2c_dev);
2252 snprintf(adap->name, sizeof(adap->name), "STM32F7 I2C(%pa)",
2253 &res->start);
2254 adap->owner = THIS_MODULE;
2255 adap->timeout = 2 * HZ;
2256 adap->retries = 3;
2257 adap->algo = &stm32f7_i2c_algo;
2258 adap->dev.parent = &pdev->dev;
2259 adap->dev.of_node = pdev->dev.of_node;
2260
2261 init_completion(&i2c_dev->complete);
2262
2263 /* Init DMA config if supported */
2264 i2c_dev->dma = stm32_i2c_dma_request(i2c_dev->dev, phy_addr,
2265 STM32F7_I2C_TXDR,
2266 STM32F7_I2C_RXDR);
2267 if (IS_ERR(i2c_dev->dma)) {
2268 ret = PTR_ERR(i2c_dev->dma);
2269 /* DMA support is optional, only report other errors */
2270 if (ret != -ENODEV)
2271 goto fmp_clear;
2272 dev_dbg(i2c_dev->dev, "No DMA option: fallback using interrupts\n");
2273 i2c_dev->dma = NULL;
2274 }
2275
2276 if (i2c_dev->wakeup_src) {
2277 device_set_wakeup_capable(i2c_dev->dev, true);
2278
2279 ret = dev_pm_set_wake_irq(i2c_dev->dev, irq_event);
2280 if (ret) {
2281 dev_err(i2c_dev->dev, "Failed to set wake up irq\n");
2282 goto clr_wakeup_capable;
2283 }
2284 }
2285
2286 platform_set_drvdata(pdev, i2c_dev);
2287
2288 pm_runtime_set_autosuspend_delay(i2c_dev->dev,
2289 STM32F7_AUTOSUSPEND_DELAY);
2290 pm_runtime_use_autosuspend(i2c_dev->dev);
2291 pm_runtime_set_active(i2c_dev->dev);
2292 pm_runtime_enable(i2c_dev->dev);
2293
2294 pm_runtime_get_noresume(&pdev->dev);
2295
2296 stm32f7_i2c_hw_config(i2c_dev);
2297
2298 i2c_dev->smbus_mode = of_property_read_bool(pdev->dev.of_node, "smbus");
2299
2300 ret = i2c_add_adapter(adap);
2301 if (ret)
2302 goto pm_disable;
2303
2304 if (i2c_dev->smbus_mode) {
2305 ret = stm32f7_i2c_enable_smbus_host(i2c_dev);
2306 if (ret) {
2307 dev_err(i2c_dev->dev,
2308 "failed to enable SMBus Host-Notify protocol (%d)\n",
2309 ret);
2310 goto i2c_adapter_remove;
2311 }
2312 }
2313
2314 if (of_property_read_bool(pdev->dev.of_node, "smbus-alert")) {
2315 ret = stm32f7_i2c_enable_smbus_alert(i2c_dev);
2316 if (ret) {
2317 dev_err(i2c_dev->dev,
2318 "failed to enable SMBus alert protocol (%d)\n",
2319 ret);
2320 goto i2c_disable_smbus_host;
2321 }
2322 }
2323
2324 dev_info(i2c_dev->dev, "STM32F7 I2C-%d bus adapter\n", adap->nr);
2325
2326 pm_runtime_mark_last_busy(i2c_dev->dev);
2327 pm_runtime_put_autosuspend(i2c_dev->dev);
2328
2329 return 0;
2330
2331 i2c_disable_smbus_host:
2332 stm32f7_i2c_disable_smbus_host(i2c_dev);
2333
2334 i2c_adapter_remove:
2335 i2c_del_adapter(adap);
2336
2337 pm_disable:
2338 pm_runtime_put_noidle(i2c_dev->dev);
2339 pm_runtime_disable(i2c_dev->dev);
2340 pm_runtime_set_suspended(i2c_dev->dev);
2341 pm_runtime_dont_use_autosuspend(i2c_dev->dev);
2342
2343 if (i2c_dev->wakeup_src)
2344 dev_pm_clear_wake_irq(i2c_dev->dev);
2345
2346 clr_wakeup_capable:
2347 if (i2c_dev->wakeup_src)
2348 device_set_wakeup_capable(i2c_dev->dev, false);
2349
2350 if (i2c_dev->dma) {
2351 stm32_i2c_dma_free(i2c_dev->dma);
2352 i2c_dev->dma = NULL;
2353 }
2354
2355 fmp_clear:
2356 stm32f7_i2c_write_fm_plus_bits(i2c_dev, false);
2357
2358 return ret;
2359 }
2360
stm32f7_i2c_remove(struct platform_device * pdev)2361 static void stm32f7_i2c_remove(struct platform_device *pdev)
2362 {
2363 struct stm32f7_i2c_dev *i2c_dev = platform_get_drvdata(pdev);
2364
2365 stm32f7_i2c_disable_smbus_alert(i2c_dev);
2366 stm32f7_i2c_disable_smbus_host(i2c_dev);
2367
2368 i2c_del_adapter(&i2c_dev->adap);
2369 pm_runtime_get_sync(i2c_dev->dev);
2370
2371 if (i2c_dev->wakeup_src) {
2372 dev_pm_clear_wake_irq(i2c_dev->dev);
2373 /*
2374 * enforce that wakeup is disabled and that the device
2375 * is marked as non wakeup capable
2376 */
2377 device_init_wakeup(i2c_dev->dev, false);
2378 }
2379
2380 pm_runtime_put_noidle(i2c_dev->dev);
2381 pm_runtime_disable(i2c_dev->dev);
2382 pm_runtime_set_suspended(i2c_dev->dev);
2383 pm_runtime_dont_use_autosuspend(i2c_dev->dev);
2384
2385 if (i2c_dev->dma) {
2386 stm32_i2c_dma_free(i2c_dev->dma);
2387 i2c_dev->dma = NULL;
2388 }
2389
2390 stm32f7_i2c_write_fm_plus_bits(i2c_dev, false);
2391 }
2392
stm32f7_i2c_runtime_suspend(struct device * dev)2393 static int __maybe_unused stm32f7_i2c_runtime_suspend(struct device *dev)
2394 {
2395 struct stm32f7_i2c_dev *i2c_dev = dev_get_drvdata(dev);
2396
2397 if (!stm32f7_i2c_is_slave_registered(i2c_dev))
2398 clk_disable(i2c_dev->clk);
2399
2400 return 0;
2401 }
2402
stm32f7_i2c_runtime_resume(struct device * dev)2403 static int __maybe_unused stm32f7_i2c_runtime_resume(struct device *dev)
2404 {
2405 struct stm32f7_i2c_dev *i2c_dev = dev_get_drvdata(dev);
2406 int ret;
2407
2408 if (!stm32f7_i2c_is_slave_registered(i2c_dev)) {
2409 ret = clk_enable(i2c_dev->clk);
2410 if (ret) {
2411 dev_err(dev, "failed to enable clock\n");
2412 return ret;
2413 }
2414 }
2415
2416 return 0;
2417 }
2418
stm32f7_i2c_regs_backup(struct stm32f7_i2c_dev * i2c_dev)2419 static int __maybe_unused stm32f7_i2c_regs_backup(struct stm32f7_i2c_dev *i2c_dev)
2420 {
2421 int ret;
2422 struct stm32f7_i2c_regs *backup_regs = &i2c_dev->backup_regs;
2423
2424 ret = pm_runtime_resume_and_get(i2c_dev->dev);
2425 if (ret < 0)
2426 return ret;
2427
2428 backup_regs->cr1 = readl_relaxed(i2c_dev->base + STM32F7_I2C_CR1);
2429 backup_regs->cr2 = readl_relaxed(i2c_dev->base + STM32F7_I2C_CR2);
2430 backup_regs->oar1 = readl_relaxed(i2c_dev->base + STM32F7_I2C_OAR1);
2431 backup_regs->oar2 = readl_relaxed(i2c_dev->base + STM32F7_I2C_OAR2);
2432 backup_regs->tmgr = readl_relaxed(i2c_dev->base + STM32F7_I2C_TIMINGR);
2433 stm32f7_i2c_write_fm_plus_bits(i2c_dev, false);
2434
2435 pm_runtime_put_sync(i2c_dev->dev);
2436
2437 return ret;
2438 }
2439
stm32f7_i2c_regs_restore(struct stm32f7_i2c_dev * i2c_dev)2440 static int __maybe_unused stm32f7_i2c_regs_restore(struct stm32f7_i2c_dev *i2c_dev)
2441 {
2442 u32 cr1;
2443 int ret;
2444 struct stm32f7_i2c_regs *backup_regs = &i2c_dev->backup_regs;
2445
2446 ret = pm_runtime_resume_and_get(i2c_dev->dev);
2447 if (ret < 0)
2448 return ret;
2449
2450 cr1 = readl_relaxed(i2c_dev->base + STM32F7_I2C_CR1);
2451 if (cr1 & STM32F7_I2C_CR1_PE)
2452 stm32f7_i2c_clr_bits(i2c_dev->base + STM32F7_I2C_CR1,
2453 STM32F7_I2C_CR1_PE);
2454
2455 writel_relaxed(backup_regs->tmgr, i2c_dev->base + STM32F7_I2C_TIMINGR);
2456 writel_relaxed(backup_regs->cr1 & ~STM32F7_I2C_CR1_PE,
2457 i2c_dev->base + STM32F7_I2C_CR1);
2458 if (backup_regs->cr1 & STM32F7_I2C_CR1_PE)
2459 stm32f7_i2c_set_bits(i2c_dev->base + STM32F7_I2C_CR1,
2460 STM32F7_I2C_CR1_PE);
2461 writel_relaxed(backup_regs->cr2, i2c_dev->base + STM32F7_I2C_CR2);
2462 writel_relaxed(backup_regs->oar1, i2c_dev->base + STM32F7_I2C_OAR1);
2463 writel_relaxed(backup_regs->oar2, i2c_dev->base + STM32F7_I2C_OAR2);
2464 stm32f7_i2c_write_fm_plus_bits(i2c_dev, true);
2465
2466 pm_runtime_put_sync(i2c_dev->dev);
2467
2468 return ret;
2469 }
2470
stm32f7_i2c_suspend(struct device * dev)2471 static int __maybe_unused stm32f7_i2c_suspend(struct device *dev)
2472 {
2473 struct stm32f7_i2c_dev *i2c_dev = dev_get_drvdata(dev);
2474 int ret;
2475
2476 i2c_mark_adapter_suspended(&i2c_dev->adap);
2477
2478 if (!device_may_wakeup(dev) && !device_wakeup_path(dev)) {
2479 ret = stm32f7_i2c_regs_backup(i2c_dev);
2480 if (ret < 0) {
2481 i2c_mark_adapter_resumed(&i2c_dev->adap);
2482 return ret;
2483 }
2484
2485 pinctrl_pm_select_sleep_state(dev);
2486 pm_runtime_force_suspend(dev);
2487 }
2488
2489 return 0;
2490 }
2491
stm32f7_i2c_resume(struct device * dev)2492 static int __maybe_unused stm32f7_i2c_resume(struct device *dev)
2493 {
2494 struct stm32f7_i2c_dev *i2c_dev = dev_get_drvdata(dev);
2495 int ret;
2496
2497 if (!device_may_wakeup(dev) && !device_wakeup_path(dev)) {
2498 ret = pm_runtime_force_resume(dev);
2499 if (ret < 0)
2500 return ret;
2501 pinctrl_pm_select_default_state(dev);
2502
2503 ret = stm32f7_i2c_regs_restore(i2c_dev);
2504 if (ret < 0)
2505 return ret;
2506 }
2507
2508 i2c_mark_adapter_resumed(&i2c_dev->adap);
2509
2510 return 0;
2511 }
2512
2513 static const struct dev_pm_ops stm32f7_i2c_pm_ops = {
2514 SET_RUNTIME_PM_OPS(stm32f7_i2c_runtime_suspend,
2515 stm32f7_i2c_runtime_resume, NULL)
2516 SET_SYSTEM_SLEEP_PM_OPS(stm32f7_i2c_suspend, stm32f7_i2c_resume)
2517 };
2518
2519 static const struct of_device_id stm32f7_i2c_match[] = {
2520 { .compatible = "st,stm32f7-i2c", .data = &stm32f7_setup},
2521 { .compatible = "st,stm32mp15-i2c", .data = &stm32mp15_setup},
2522 { .compatible = "st,stm32mp13-i2c", .data = &stm32mp13_setup},
2523 { .compatible = "st,stm32mp25-i2c", .data = &stm32mp25_setup},
2524 {},
2525 };
2526 MODULE_DEVICE_TABLE(of, stm32f7_i2c_match);
2527
2528 static struct platform_driver stm32f7_i2c_driver = {
2529 .driver = {
2530 .name = "stm32f7-i2c",
2531 .of_match_table = stm32f7_i2c_match,
2532 .pm = &stm32f7_i2c_pm_ops,
2533 },
2534 .probe = stm32f7_i2c_probe,
2535 .remove_new = stm32f7_i2c_remove,
2536 };
2537
2538 module_platform_driver(stm32f7_i2c_driver);
2539
2540 MODULE_AUTHOR("M'boumba Cedric Madianga <cedric.madianga@gmail.com>");
2541 MODULE_DESCRIPTION("STMicroelectronics STM32F7 I2C driver");
2542 MODULE_LICENSE("GPL v2");
2543