1 // SPDX-License-Identifier: GPL-2.0+
2 /*
3 * This is i.MX low power i2c controller driver.
4 *
5 * Copyright 2016 Freescale Semiconductor, Inc.
6 */
7
8 #include <linux/clk.h>
9 #include <linux/completion.h>
10 #include <linux/delay.h>
11 #include <linux/err.h>
12 #include <linux/errno.h>
13 #include <linux/i2c.h>
14 #include <linux/init.h>
15 #include <linux/interrupt.h>
16 #include <linux/io.h>
17 #include <linux/kernel.h>
18 #include <linux/module.h>
19 #include <linux/of.h>
20 #include <linux/pinctrl/consumer.h>
21 #include <linux/platform_device.h>
22 #include <linux/pm_runtime.h>
23 #include <linux/sched.h>
24 #include <linux/slab.h>
25
26 #define DRIVER_NAME "imx-lpi2c"
27
28 #define LPI2C_PARAM 0x04 /* i2c RX/TX FIFO size */
29 #define LPI2C_MCR 0x10 /* i2c contrl register */
30 #define LPI2C_MSR 0x14 /* i2c status register */
31 #define LPI2C_MIER 0x18 /* i2c interrupt enable */
32 #define LPI2C_MCFGR0 0x20 /* i2c master configuration */
33 #define LPI2C_MCFGR1 0x24 /* i2c master configuration */
34 #define LPI2C_MCFGR2 0x28 /* i2c master configuration */
35 #define LPI2C_MCFGR3 0x2C /* i2c master configuration */
36 #define LPI2C_MCCR0 0x48 /* i2c master clk configuration */
37 #define LPI2C_MCCR1 0x50 /* i2c master clk configuration */
38 #define LPI2C_MFCR 0x58 /* i2c master FIFO control */
39 #define LPI2C_MFSR 0x5C /* i2c master FIFO status */
40 #define LPI2C_MTDR 0x60 /* i2c master TX data register */
41 #define LPI2C_MRDR 0x70 /* i2c master RX data register */
42
43 /* i2c command */
44 #define TRAN_DATA 0X00
45 #define RECV_DATA 0X01
46 #define GEN_STOP 0X02
47 #define RECV_DISCARD 0X03
48 #define GEN_START 0X04
49 #define START_NACK 0X05
50 #define START_HIGH 0X06
51 #define START_HIGH_NACK 0X07
52
53 #define MCR_MEN BIT(0)
54 #define MCR_RST BIT(1)
55 #define MCR_DOZEN BIT(2)
56 #define MCR_DBGEN BIT(3)
57 #define MCR_RTF BIT(8)
58 #define MCR_RRF BIT(9)
59 #define MSR_TDF BIT(0)
60 #define MSR_RDF BIT(1)
61 #define MSR_SDF BIT(9)
62 #define MSR_NDF BIT(10)
63 #define MSR_ALF BIT(11)
64 #define MSR_MBF BIT(24)
65 #define MSR_BBF BIT(25)
66 #define MIER_TDIE BIT(0)
67 #define MIER_RDIE BIT(1)
68 #define MIER_SDIE BIT(9)
69 #define MIER_NDIE BIT(10)
70 #define MCFGR1_AUTOSTOP BIT(8)
71 #define MCFGR1_IGNACK BIT(9)
72 #define MRDR_RXEMPTY BIT(14)
73
74 #define I2C_CLK_RATIO 2
75 #define CHUNK_DATA 256
76
77 #define I2C_PM_TIMEOUT 10 /* ms */
78
79 enum lpi2c_imx_mode {
80 STANDARD, /* 100+Kbps */
81 FAST, /* 400+Kbps */
82 FAST_PLUS, /* 1.0+Mbps */
83 HS, /* 3.4+Mbps */
84 ULTRA_FAST, /* 5.0+Mbps */
85 };
86
87 enum lpi2c_imx_pincfg {
88 TWO_PIN_OD,
89 TWO_PIN_OO,
90 TWO_PIN_PP,
91 FOUR_PIN_PP,
92 };
93
94 struct lpi2c_imx_struct {
95 struct i2c_adapter adapter;
96 int num_clks;
97 struct clk_bulk_data *clks;
98 void __iomem *base;
99 __u8 *rx_buf;
100 __u8 *tx_buf;
101 struct completion complete;
102 unsigned long rate_per;
103 unsigned int msglen;
104 unsigned int delivered;
105 unsigned int block_data;
106 unsigned int bitrate;
107 unsigned int txfifosize;
108 unsigned int rxfifosize;
109 enum lpi2c_imx_mode mode;
110 struct i2c_bus_recovery_info rinfo;
111 };
112
lpi2c_imx_intctrl(struct lpi2c_imx_struct * lpi2c_imx,unsigned int enable)113 static void lpi2c_imx_intctrl(struct lpi2c_imx_struct *lpi2c_imx,
114 unsigned int enable)
115 {
116 writel(enable, lpi2c_imx->base + LPI2C_MIER);
117 }
118
lpi2c_imx_bus_busy(struct lpi2c_imx_struct * lpi2c_imx)119 static int lpi2c_imx_bus_busy(struct lpi2c_imx_struct *lpi2c_imx)
120 {
121 unsigned long orig_jiffies = jiffies;
122 unsigned int temp;
123
124 while (1) {
125 temp = readl(lpi2c_imx->base + LPI2C_MSR);
126
127 /* check for arbitration lost, clear if set */
128 if (temp & MSR_ALF) {
129 writel(temp, lpi2c_imx->base + LPI2C_MSR);
130 return -EAGAIN;
131 }
132
133 if (temp & (MSR_BBF | MSR_MBF))
134 break;
135
136 if (time_after(jiffies, orig_jiffies + msecs_to_jiffies(500))) {
137 dev_dbg(&lpi2c_imx->adapter.dev, "bus not work\n");
138 if (lpi2c_imx->adapter.bus_recovery_info)
139 i2c_recover_bus(&lpi2c_imx->adapter);
140 return -ETIMEDOUT;
141 }
142 schedule();
143 }
144
145 return 0;
146 }
147
lpi2c_imx_set_mode(struct lpi2c_imx_struct * lpi2c_imx)148 static void lpi2c_imx_set_mode(struct lpi2c_imx_struct *lpi2c_imx)
149 {
150 unsigned int bitrate = lpi2c_imx->bitrate;
151 enum lpi2c_imx_mode mode;
152
153 if (bitrate < I2C_MAX_FAST_MODE_FREQ)
154 mode = STANDARD;
155 else if (bitrate < I2C_MAX_FAST_MODE_PLUS_FREQ)
156 mode = FAST;
157 else if (bitrate < I2C_MAX_HIGH_SPEED_MODE_FREQ)
158 mode = FAST_PLUS;
159 else if (bitrate < I2C_MAX_ULTRA_FAST_MODE_FREQ)
160 mode = HS;
161 else
162 mode = ULTRA_FAST;
163
164 lpi2c_imx->mode = mode;
165 }
166
lpi2c_imx_start(struct lpi2c_imx_struct * lpi2c_imx,struct i2c_msg * msgs)167 static int lpi2c_imx_start(struct lpi2c_imx_struct *lpi2c_imx,
168 struct i2c_msg *msgs)
169 {
170 unsigned int temp;
171
172 temp = readl(lpi2c_imx->base + LPI2C_MCR);
173 temp |= MCR_RRF | MCR_RTF;
174 writel(temp, lpi2c_imx->base + LPI2C_MCR);
175 writel(0x7f00, lpi2c_imx->base + LPI2C_MSR);
176
177 temp = i2c_8bit_addr_from_msg(msgs) | (GEN_START << 8);
178 writel(temp, lpi2c_imx->base + LPI2C_MTDR);
179
180 return lpi2c_imx_bus_busy(lpi2c_imx);
181 }
182
lpi2c_imx_stop(struct lpi2c_imx_struct * lpi2c_imx)183 static void lpi2c_imx_stop(struct lpi2c_imx_struct *lpi2c_imx)
184 {
185 unsigned long orig_jiffies = jiffies;
186 unsigned int temp;
187
188 writel(GEN_STOP << 8, lpi2c_imx->base + LPI2C_MTDR);
189
190 do {
191 temp = readl(lpi2c_imx->base + LPI2C_MSR);
192 if (temp & MSR_SDF)
193 break;
194
195 if (time_after(jiffies, orig_jiffies + msecs_to_jiffies(500))) {
196 dev_dbg(&lpi2c_imx->adapter.dev, "stop timeout\n");
197 if (lpi2c_imx->adapter.bus_recovery_info)
198 i2c_recover_bus(&lpi2c_imx->adapter);
199 break;
200 }
201 schedule();
202
203 } while (1);
204 }
205
206 /* CLKLO = I2C_CLK_RATIO * CLKHI, SETHOLD = CLKHI, DATAVD = CLKHI/2 */
lpi2c_imx_config(struct lpi2c_imx_struct * lpi2c_imx)207 static int lpi2c_imx_config(struct lpi2c_imx_struct *lpi2c_imx)
208 {
209 u8 prescale, filt, sethold, datavd;
210 unsigned int clk_rate, clk_cycle, clkhi, clklo;
211 enum lpi2c_imx_pincfg pincfg;
212 unsigned int temp;
213
214 lpi2c_imx_set_mode(lpi2c_imx);
215
216 clk_rate = lpi2c_imx->rate_per;
217
218 if (lpi2c_imx->mode == HS || lpi2c_imx->mode == ULTRA_FAST)
219 filt = 0;
220 else
221 filt = 2;
222
223 for (prescale = 0; prescale <= 7; prescale++) {
224 clk_cycle = clk_rate / ((1 << prescale) * lpi2c_imx->bitrate)
225 - 3 - (filt >> 1);
226 clkhi = DIV_ROUND_UP(clk_cycle, I2C_CLK_RATIO + 1);
227 clklo = clk_cycle - clkhi;
228 if (clklo < 64)
229 break;
230 }
231
232 if (prescale > 7)
233 return -EINVAL;
234
235 /* set MCFGR1: PINCFG, PRESCALE, IGNACK */
236 if (lpi2c_imx->mode == ULTRA_FAST)
237 pincfg = TWO_PIN_OO;
238 else
239 pincfg = TWO_PIN_OD;
240 temp = prescale | pincfg << 24;
241
242 if (lpi2c_imx->mode == ULTRA_FAST)
243 temp |= MCFGR1_IGNACK;
244
245 writel(temp, lpi2c_imx->base + LPI2C_MCFGR1);
246
247 /* set MCFGR2: FILTSDA, FILTSCL */
248 temp = (filt << 16) | (filt << 24);
249 writel(temp, lpi2c_imx->base + LPI2C_MCFGR2);
250
251 /* set MCCR: DATAVD, SETHOLD, CLKHI, CLKLO */
252 sethold = clkhi;
253 datavd = clkhi >> 1;
254 temp = datavd << 24 | sethold << 16 | clkhi << 8 | clklo;
255
256 if (lpi2c_imx->mode == HS)
257 writel(temp, lpi2c_imx->base + LPI2C_MCCR1);
258 else
259 writel(temp, lpi2c_imx->base + LPI2C_MCCR0);
260
261 return 0;
262 }
263
lpi2c_imx_master_enable(struct lpi2c_imx_struct * lpi2c_imx)264 static int lpi2c_imx_master_enable(struct lpi2c_imx_struct *lpi2c_imx)
265 {
266 unsigned int temp;
267 int ret;
268
269 ret = pm_runtime_resume_and_get(lpi2c_imx->adapter.dev.parent);
270 if (ret < 0)
271 return ret;
272
273 temp = MCR_RST;
274 writel(temp, lpi2c_imx->base + LPI2C_MCR);
275 writel(0, lpi2c_imx->base + LPI2C_MCR);
276
277 ret = lpi2c_imx_config(lpi2c_imx);
278 if (ret)
279 goto rpm_put;
280
281 temp = readl(lpi2c_imx->base + LPI2C_MCR);
282 temp |= MCR_MEN;
283 writel(temp, lpi2c_imx->base + LPI2C_MCR);
284
285 return 0;
286
287 rpm_put:
288 pm_runtime_mark_last_busy(lpi2c_imx->adapter.dev.parent);
289 pm_runtime_put_autosuspend(lpi2c_imx->adapter.dev.parent);
290
291 return ret;
292 }
293
lpi2c_imx_master_disable(struct lpi2c_imx_struct * lpi2c_imx)294 static int lpi2c_imx_master_disable(struct lpi2c_imx_struct *lpi2c_imx)
295 {
296 u32 temp;
297
298 temp = readl(lpi2c_imx->base + LPI2C_MCR);
299 temp &= ~MCR_MEN;
300 writel(temp, lpi2c_imx->base + LPI2C_MCR);
301
302 pm_runtime_mark_last_busy(lpi2c_imx->adapter.dev.parent);
303 pm_runtime_put_autosuspend(lpi2c_imx->adapter.dev.parent);
304
305 return 0;
306 }
307
lpi2c_imx_msg_complete(struct lpi2c_imx_struct * lpi2c_imx)308 static int lpi2c_imx_msg_complete(struct lpi2c_imx_struct *lpi2c_imx)
309 {
310 unsigned long time_left;
311
312 time_left = wait_for_completion_timeout(&lpi2c_imx->complete, HZ);
313
314 return time_left ? 0 : -ETIMEDOUT;
315 }
316
lpi2c_imx_txfifo_empty(struct lpi2c_imx_struct * lpi2c_imx)317 static int lpi2c_imx_txfifo_empty(struct lpi2c_imx_struct *lpi2c_imx)
318 {
319 unsigned long orig_jiffies = jiffies;
320 u32 txcnt;
321
322 do {
323 txcnt = readl(lpi2c_imx->base + LPI2C_MFSR) & 0xff;
324
325 if (readl(lpi2c_imx->base + LPI2C_MSR) & MSR_NDF) {
326 dev_dbg(&lpi2c_imx->adapter.dev, "NDF detected\n");
327 return -EIO;
328 }
329
330 if (time_after(jiffies, orig_jiffies + msecs_to_jiffies(500))) {
331 dev_dbg(&lpi2c_imx->adapter.dev, "txfifo empty timeout\n");
332 if (lpi2c_imx->adapter.bus_recovery_info)
333 i2c_recover_bus(&lpi2c_imx->adapter);
334 return -ETIMEDOUT;
335 }
336 schedule();
337
338 } while (txcnt);
339
340 return 0;
341 }
342
lpi2c_imx_set_tx_watermark(struct lpi2c_imx_struct * lpi2c_imx)343 static void lpi2c_imx_set_tx_watermark(struct lpi2c_imx_struct *lpi2c_imx)
344 {
345 writel(lpi2c_imx->txfifosize >> 1, lpi2c_imx->base + LPI2C_MFCR);
346 }
347
lpi2c_imx_set_rx_watermark(struct lpi2c_imx_struct * lpi2c_imx)348 static void lpi2c_imx_set_rx_watermark(struct lpi2c_imx_struct *lpi2c_imx)
349 {
350 unsigned int temp, remaining;
351
352 remaining = lpi2c_imx->msglen - lpi2c_imx->delivered;
353
354 if (remaining > (lpi2c_imx->rxfifosize >> 1))
355 temp = lpi2c_imx->rxfifosize >> 1;
356 else
357 temp = 0;
358
359 writel(temp << 16, lpi2c_imx->base + LPI2C_MFCR);
360 }
361
lpi2c_imx_write_txfifo(struct lpi2c_imx_struct * lpi2c_imx)362 static void lpi2c_imx_write_txfifo(struct lpi2c_imx_struct *lpi2c_imx)
363 {
364 unsigned int data, txcnt;
365
366 txcnt = readl(lpi2c_imx->base + LPI2C_MFSR) & 0xff;
367
368 while (txcnt < lpi2c_imx->txfifosize) {
369 if (lpi2c_imx->delivered == lpi2c_imx->msglen)
370 break;
371
372 data = lpi2c_imx->tx_buf[lpi2c_imx->delivered++];
373 writel(data, lpi2c_imx->base + LPI2C_MTDR);
374 txcnt++;
375 }
376
377 if (lpi2c_imx->delivered < lpi2c_imx->msglen)
378 lpi2c_imx_intctrl(lpi2c_imx, MIER_TDIE | MIER_NDIE);
379 else
380 complete(&lpi2c_imx->complete);
381 }
382
lpi2c_imx_read_rxfifo(struct lpi2c_imx_struct * lpi2c_imx)383 static void lpi2c_imx_read_rxfifo(struct lpi2c_imx_struct *lpi2c_imx)
384 {
385 unsigned int blocklen, remaining;
386 unsigned int temp, data;
387
388 do {
389 data = readl(lpi2c_imx->base + LPI2C_MRDR);
390 if (data & MRDR_RXEMPTY)
391 break;
392
393 lpi2c_imx->rx_buf[lpi2c_imx->delivered++] = data & 0xff;
394 } while (1);
395
396 /*
397 * First byte is the length of remaining packet in the SMBus block
398 * data read. Add it to msgs->len.
399 */
400 if (lpi2c_imx->block_data) {
401 blocklen = lpi2c_imx->rx_buf[0];
402 lpi2c_imx->msglen += blocklen;
403 }
404
405 remaining = lpi2c_imx->msglen - lpi2c_imx->delivered;
406
407 if (!remaining) {
408 complete(&lpi2c_imx->complete);
409 return;
410 }
411
412 /* not finished, still waiting for rx data */
413 lpi2c_imx_set_rx_watermark(lpi2c_imx);
414
415 /* multiple receive commands */
416 if (lpi2c_imx->block_data) {
417 lpi2c_imx->block_data = 0;
418 temp = remaining;
419 temp |= (RECV_DATA << 8);
420 writel(temp, lpi2c_imx->base + LPI2C_MTDR);
421 } else if (!(lpi2c_imx->delivered & 0xff)) {
422 temp = (remaining > CHUNK_DATA ? CHUNK_DATA : remaining) - 1;
423 temp |= (RECV_DATA << 8);
424 writel(temp, lpi2c_imx->base + LPI2C_MTDR);
425 }
426
427 lpi2c_imx_intctrl(lpi2c_imx, MIER_RDIE);
428 }
429
lpi2c_imx_write(struct lpi2c_imx_struct * lpi2c_imx,struct i2c_msg * msgs)430 static void lpi2c_imx_write(struct lpi2c_imx_struct *lpi2c_imx,
431 struct i2c_msg *msgs)
432 {
433 lpi2c_imx->tx_buf = msgs->buf;
434 lpi2c_imx_set_tx_watermark(lpi2c_imx);
435 lpi2c_imx_write_txfifo(lpi2c_imx);
436 }
437
lpi2c_imx_read(struct lpi2c_imx_struct * lpi2c_imx,struct i2c_msg * msgs)438 static void lpi2c_imx_read(struct lpi2c_imx_struct *lpi2c_imx,
439 struct i2c_msg *msgs)
440 {
441 unsigned int temp;
442
443 lpi2c_imx->rx_buf = msgs->buf;
444 lpi2c_imx->block_data = msgs->flags & I2C_M_RECV_LEN;
445
446 lpi2c_imx_set_rx_watermark(lpi2c_imx);
447 temp = msgs->len > CHUNK_DATA ? CHUNK_DATA - 1 : msgs->len - 1;
448 temp |= (RECV_DATA << 8);
449 writel(temp, lpi2c_imx->base + LPI2C_MTDR);
450
451 lpi2c_imx_intctrl(lpi2c_imx, MIER_RDIE | MIER_NDIE);
452 }
453
lpi2c_imx_xfer(struct i2c_adapter * adapter,struct i2c_msg * msgs,int num)454 static int lpi2c_imx_xfer(struct i2c_adapter *adapter,
455 struct i2c_msg *msgs, int num)
456 {
457 struct lpi2c_imx_struct *lpi2c_imx = i2c_get_adapdata(adapter);
458 unsigned int temp;
459 int i, result;
460
461 result = lpi2c_imx_master_enable(lpi2c_imx);
462 if (result)
463 return result;
464
465 for (i = 0; i < num; i++) {
466 result = lpi2c_imx_start(lpi2c_imx, &msgs[i]);
467 if (result)
468 goto disable;
469
470 /* quick smbus */
471 if (num == 1 && msgs[0].len == 0)
472 goto stop;
473
474 lpi2c_imx->rx_buf = NULL;
475 lpi2c_imx->tx_buf = NULL;
476 lpi2c_imx->delivered = 0;
477 lpi2c_imx->msglen = msgs[i].len;
478 init_completion(&lpi2c_imx->complete);
479
480 if (msgs[i].flags & I2C_M_RD)
481 lpi2c_imx_read(lpi2c_imx, &msgs[i]);
482 else
483 lpi2c_imx_write(lpi2c_imx, &msgs[i]);
484
485 result = lpi2c_imx_msg_complete(lpi2c_imx);
486 if (result)
487 goto stop;
488
489 if (!(msgs[i].flags & I2C_M_RD)) {
490 result = lpi2c_imx_txfifo_empty(lpi2c_imx);
491 if (result)
492 goto stop;
493 }
494 }
495
496 stop:
497 lpi2c_imx_stop(lpi2c_imx);
498
499 temp = readl(lpi2c_imx->base + LPI2C_MSR);
500 if ((temp & MSR_NDF) && !result)
501 result = -EIO;
502
503 disable:
504 lpi2c_imx_master_disable(lpi2c_imx);
505
506 dev_dbg(&lpi2c_imx->adapter.dev, "<%s> exit with: %s: %d\n", __func__,
507 (result < 0) ? "error" : "success msg",
508 (result < 0) ? result : num);
509
510 return (result < 0) ? result : num;
511 }
512
lpi2c_imx_isr(int irq,void * dev_id)513 static irqreturn_t lpi2c_imx_isr(int irq, void *dev_id)
514 {
515 struct lpi2c_imx_struct *lpi2c_imx = dev_id;
516 unsigned int enabled;
517 unsigned int temp;
518
519 enabled = readl(lpi2c_imx->base + LPI2C_MIER);
520
521 lpi2c_imx_intctrl(lpi2c_imx, 0);
522 temp = readl(lpi2c_imx->base + LPI2C_MSR);
523 temp &= enabled;
524
525 if (temp & MSR_NDF)
526 complete(&lpi2c_imx->complete);
527 else if (temp & MSR_RDF)
528 lpi2c_imx_read_rxfifo(lpi2c_imx);
529 else if (temp & MSR_TDF)
530 lpi2c_imx_write_txfifo(lpi2c_imx);
531
532 return IRQ_HANDLED;
533 }
534
lpi2c_imx_init_recovery_info(struct lpi2c_imx_struct * lpi2c_imx,struct platform_device * pdev)535 static int lpi2c_imx_init_recovery_info(struct lpi2c_imx_struct *lpi2c_imx,
536 struct platform_device *pdev)
537 {
538 struct i2c_bus_recovery_info *bri = &lpi2c_imx->rinfo;
539
540 bri->pinctrl = devm_pinctrl_get(&pdev->dev);
541 if (IS_ERR(bri->pinctrl))
542 return PTR_ERR(bri->pinctrl);
543
544 lpi2c_imx->adapter.bus_recovery_info = bri;
545
546 return 0;
547 }
548
lpi2c_imx_func(struct i2c_adapter * adapter)549 static u32 lpi2c_imx_func(struct i2c_adapter *adapter)
550 {
551 return I2C_FUNC_I2C | I2C_FUNC_SMBUS_EMUL |
552 I2C_FUNC_SMBUS_READ_BLOCK_DATA;
553 }
554
555 static const struct i2c_algorithm lpi2c_imx_algo = {
556 .master_xfer = lpi2c_imx_xfer,
557 .functionality = lpi2c_imx_func,
558 };
559
560 static const struct of_device_id lpi2c_imx_of_match[] = {
561 { .compatible = "fsl,imx7ulp-lpi2c" },
562 { }
563 };
564 MODULE_DEVICE_TABLE(of, lpi2c_imx_of_match);
565
lpi2c_imx_probe(struct platform_device * pdev)566 static int lpi2c_imx_probe(struct platform_device *pdev)
567 {
568 struct lpi2c_imx_struct *lpi2c_imx;
569 unsigned int temp;
570 int irq, ret;
571
572 lpi2c_imx = devm_kzalloc(&pdev->dev, sizeof(*lpi2c_imx), GFP_KERNEL);
573 if (!lpi2c_imx)
574 return -ENOMEM;
575
576 lpi2c_imx->base = devm_platform_ioremap_resource(pdev, 0);
577 if (IS_ERR(lpi2c_imx->base))
578 return PTR_ERR(lpi2c_imx->base);
579
580 irq = platform_get_irq(pdev, 0);
581 if (irq < 0)
582 return irq;
583
584 lpi2c_imx->adapter.owner = THIS_MODULE;
585 lpi2c_imx->adapter.algo = &lpi2c_imx_algo;
586 lpi2c_imx->adapter.dev.parent = &pdev->dev;
587 lpi2c_imx->adapter.dev.of_node = pdev->dev.of_node;
588 strscpy(lpi2c_imx->adapter.name, pdev->name,
589 sizeof(lpi2c_imx->adapter.name));
590
591 ret = devm_clk_bulk_get_all(&pdev->dev, &lpi2c_imx->clks);
592 if (ret < 0)
593 return dev_err_probe(&pdev->dev, ret, "can't get I2C peripheral clock\n");
594 lpi2c_imx->num_clks = ret;
595
596 ret = of_property_read_u32(pdev->dev.of_node,
597 "clock-frequency", &lpi2c_imx->bitrate);
598 if (ret)
599 lpi2c_imx->bitrate = I2C_MAX_STANDARD_MODE_FREQ;
600
601 ret = devm_request_irq(&pdev->dev, irq, lpi2c_imx_isr, 0,
602 pdev->name, lpi2c_imx);
603 if (ret)
604 return dev_err_probe(&pdev->dev, ret, "can't claim irq %d\n", irq);
605
606 i2c_set_adapdata(&lpi2c_imx->adapter, lpi2c_imx);
607 platform_set_drvdata(pdev, lpi2c_imx);
608
609 ret = clk_bulk_prepare_enable(lpi2c_imx->num_clks, lpi2c_imx->clks);
610 if (ret)
611 return ret;
612
613 /*
614 * Lock the parent clock rate to avoid getting parent clock upon
615 * each transfer
616 */
617 ret = devm_clk_rate_exclusive_get(&pdev->dev, lpi2c_imx->clks[0].clk);
618 if (ret)
619 return dev_err_probe(&pdev->dev, ret,
620 "can't lock I2C peripheral clock rate\n");
621
622 lpi2c_imx->rate_per = clk_get_rate(lpi2c_imx->clks[0].clk);
623 if (!lpi2c_imx->rate_per)
624 return dev_err_probe(&pdev->dev, -EINVAL,
625 "can't get I2C peripheral clock rate\n");
626
627 pm_runtime_set_autosuspend_delay(&pdev->dev, I2C_PM_TIMEOUT);
628 pm_runtime_use_autosuspend(&pdev->dev);
629 pm_runtime_get_noresume(&pdev->dev);
630 pm_runtime_set_active(&pdev->dev);
631 pm_runtime_enable(&pdev->dev);
632
633 temp = readl(lpi2c_imx->base + LPI2C_PARAM);
634 lpi2c_imx->txfifosize = 1 << (temp & 0x0f);
635 lpi2c_imx->rxfifosize = 1 << ((temp >> 8) & 0x0f);
636
637 /* Init optional bus recovery function */
638 ret = lpi2c_imx_init_recovery_info(lpi2c_imx, pdev);
639 /* Give it another chance if pinctrl used is not ready yet */
640 if (ret == -EPROBE_DEFER)
641 goto rpm_disable;
642
643 ret = i2c_add_adapter(&lpi2c_imx->adapter);
644 if (ret)
645 goto rpm_disable;
646
647 pm_runtime_mark_last_busy(&pdev->dev);
648 pm_runtime_put_autosuspend(&pdev->dev);
649
650 dev_info(&lpi2c_imx->adapter.dev, "LPI2C adapter registered\n");
651
652 return 0;
653
654 rpm_disable:
655 pm_runtime_put(&pdev->dev);
656 pm_runtime_disable(&pdev->dev);
657 pm_runtime_dont_use_autosuspend(&pdev->dev);
658
659 return ret;
660 }
661
lpi2c_imx_remove(struct platform_device * pdev)662 static void lpi2c_imx_remove(struct platform_device *pdev)
663 {
664 struct lpi2c_imx_struct *lpi2c_imx = platform_get_drvdata(pdev);
665
666 i2c_del_adapter(&lpi2c_imx->adapter);
667
668 pm_runtime_disable(&pdev->dev);
669 pm_runtime_dont_use_autosuspend(&pdev->dev);
670 }
671
lpi2c_runtime_suspend(struct device * dev)672 static int __maybe_unused lpi2c_runtime_suspend(struct device *dev)
673 {
674 struct lpi2c_imx_struct *lpi2c_imx = dev_get_drvdata(dev);
675
676 clk_bulk_disable(lpi2c_imx->num_clks, lpi2c_imx->clks);
677 pinctrl_pm_select_sleep_state(dev);
678
679 return 0;
680 }
681
lpi2c_runtime_resume(struct device * dev)682 static int __maybe_unused lpi2c_runtime_resume(struct device *dev)
683 {
684 struct lpi2c_imx_struct *lpi2c_imx = dev_get_drvdata(dev);
685 int ret;
686
687 pinctrl_pm_select_default_state(dev);
688 ret = clk_bulk_enable(lpi2c_imx->num_clks, lpi2c_imx->clks);
689 if (ret) {
690 dev_err(dev, "failed to enable I2C clock, ret=%d\n", ret);
691 return ret;
692 }
693
694 return 0;
695 }
696
697 static const struct dev_pm_ops lpi2c_pm_ops = {
698 SET_NOIRQ_SYSTEM_SLEEP_PM_OPS(pm_runtime_force_suspend,
699 pm_runtime_force_resume)
700 SET_RUNTIME_PM_OPS(lpi2c_runtime_suspend,
701 lpi2c_runtime_resume, NULL)
702 };
703
704 static struct platform_driver lpi2c_imx_driver = {
705 .probe = lpi2c_imx_probe,
706 .remove_new = lpi2c_imx_remove,
707 .driver = {
708 .name = DRIVER_NAME,
709 .of_match_table = lpi2c_imx_of_match,
710 .pm = &lpi2c_pm_ops,
711 },
712 };
713
714 module_platform_driver(lpi2c_imx_driver);
715
716 MODULE_AUTHOR("Gao Pan <pandy.gao@nxp.com>");
717 MODULE_DESCRIPTION("I2C adapter driver for LPI2C bus");
718 MODULE_LICENSE("GPL");
719