xref: /linux/drivers/i2c/busses/i2c-imx-lpi2c.c (revision e6a901a00822659181c93c86d8bbc2a17779fddc)
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 int		msglen;
103 	unsigned int		delivered;
104 	unsigned int		block_data;
105 	unsigned int		bitrate;
106 	unsigned int		txfifosize;
107 	unsigned int		rxfifosize;
108 	enum lpi2c_imx_mode	mode;
109 	struct i2c_bus_recovery_info rinfo;
110 };
111 
112 static void lpi2c_imx_intctrl(struct lpi2c_imx_struct *lpi2c_imx,
113 			      unsigned int enable)
114 {
115 	writel(enable, lpi2c_imx->base + LPI2C_MIER);
116 }
117 
118 static int lpi2c_imx_bus_busy(struct lpi2c_imx_struct *lpi2c_imx)
119 {
120 	unsigned long orig_jiffies = jiffies;
121 	unsigned int temp;
122 
123 	while (1) {
124 		temp = readl(lpi2c_imx->base + LPI2C_MSR);
125 
126 		/* check for arbitration lost, clear if set */
127 		if (temp & MSR_ALF) {
128 			writel(temp, lpi2c_imx->base + LPI2C_MSR);
129 			return -EAGAIN;
130 		}
131 
132 		if (temp & (MSR_BBF | MSR_MBF))
133 			break;
134 
135 		if (time_after(jiffies, orig_jiffies + msecs_to_jiffies(500))) {
136 			dev_dbg(&lpi2c_imx->adapter.dev, "bus not work\n");
137 			if (lpi2c_imx->adapter.bus_recovery_info)
138 				i2c_recover_bus(&lpi2c_imx->adapter);
139 			return -ETIMEDOUT;
140 		}
141 		schedule();
142 	}
143 
144 	return 0;
145 }
146 
147 static void lpi2c_imx_set_mode(struct lpi2c_imx_struct *lpi2c_imx)
148 {
149 	unsigned int bitrate = lpi2c_imx->bitrate;
150 	enum lpi2c_imx_mode mode;
151 
152 	if (bitrate < I2C_MAX_FAST_MODE_FREQ)
153 		mode = STANDARD;
154 	else if (bitrate < I2C_MAX_FAST_MODE_PLUS_FREQ)
155 		mode = FAST;
156 	else if (bitrate < I2C_MAX_HIGH_SPEED_MODE_FREQ)
157 		mode = FAST_PLUS;
158 	else if (bitrate < I2C_MAX_ULTRA_FAST_MODE_FREQ)
159 		mode = HS;
160 	else
161 		mode = ULTRA_FAST;
162 
163 	lpi2c_imx->mode = mode;
164 }
165 
166 static int lpi2c_imx_start(struct lpi2c_imx_struct *lpi2c_imx,
167 			   struct i2c_msg *msgs)
168 {
169 	unsigned int temp;
170 
171 	temp = readl(lpi2c_imx->base + LPI2C_MCR);
172 	temp |= MCR_RRF | MCR_RTF;
173 	writel(temp, lpi2c_imx->base + LPI2C_MCR);
174 	writel(0x7f00, lpi2c_imx->base + LPI2C_MSR);
175 
176 	temp = i2c_8bit_addr_from_msg(msgs) | (GEN_START << 8);
177 	writel(temp, lpi2c_imx->base + LPI2C_MTDR);
178 
179 	return lpi2c_imx_bus_busy(lpi2c_imx);
180 }
181 
182 static void lpi2c_imx_stop(struct lpi2c_imx_struct *lpi2c_imx)
183 {
184 	unsigned long orig_jiffies = jiffies;
185 	unsigned int temp;
186 
187 	writel(GEN_STOP << 8, lpi2c_imx->base + LPI2C_MTDR);
188 
189 	do {
190 		temp = readl(lpi2c_imx->base + LPI2C_MSR);
191 		if (temp & MSR_SDF)
192 			break;
193 
194 		if (time_after(jiffies, orig_jiffies + msecs_to_jiffies(500))) {
195 			dev_dbg(&lpi2c_imx->adapter.dev, "stop timeout\n");
196 			if (lpi2c_imx->adapter.bus_recovery_info)
197 				i2c_recover_bus(&lpi2c_imx->adapter);
198 			break;
199 		}
200 		schedule();
201 
202 	} while (1);
203 }
204 
205 /* CLKLO = I2C_CLK_RATIO * CLKHI, SETHOLD = CLKHI, DATAVD = CLKHI/2 */
206 static int lpi2c_imx_config(struct lpi2c_imx_struct *lpi2c_imx)
207 {
208 	u8 prescale, filt, sethold, datavd;
209 	unsigned int clk_rate, clk_cycle, clkhi, clklo;
210 	enum lpi2c_imx_pincfg pincfg;
211 	unsigned int temp;
212 
213 	lpi2c_imx_set_mode(lpi2c_imx);
214 
215 	clk_rate = clk_get_rate(lpi2c_imx->clks[0].clk);
216 	if (!clk_rate)
217 		return -EINVAL;
218 
219 	if (lpi2c_imx->mode == HS || lpi2c_imx->mode == ULTRA_FAST)
220 		filt = 0;
221 	else
222 		filt = 2;
223 
224 	for (prescale = 0; prescale <= 7; prescale++) {
225 		clk_cycle = clk_rate / ((1 << prescale) * lpi2c_imx->bitrate)
226 			    - 3 - (filt >> 1);
227 		clkhi = DIV_ROUND_UP(clk_cycle, I2C_CLK_RATIO + 1);
228 		clklo = clk_cycle - clkhi;
229 		if (clklo < 64)
230 			break;
231 	}
232 
233 	if (prescale > 7)
234 		return -EINVAL;
235 
236 	/* set MCFGR1: PINCFG, PRESCALE, IGNACK */
237 	if (lpi2c_imx->mode == ULTRA_FAST)
238 		pincfg = TWO_PIN_OO;
239 	else
240 		pincfg = TWO_PIN_OD;
241 	temp = prescale | pincfg << 24;
242 
243 	if (lpi2c_imx->mode == ULTRA_FAST)
244 		temp |= MCFGR1_IGNACK;
245 
246 	writel(temp, lpi2c_imx->base + LPI2C_MCFGR1);
247 
248 	/* set MCFGR2: FILTSDA, FILTSCL */
249 	temp = (filt << 16) | (filt << 24);
250 	writel(temp, lpi2c_imx->base + LPI2C_MCFGR2);
251 
252 	/* set MCCR: DATAVD, SETHOLD, CLKHI, CLKLO */
253 	sethold = clkhi;
254 	datavd = clkhi >> 1;
255 	temp = datavd << 24 | sethold << 16 | clkhi << 8 | clklo;
256 
257 	if (lpi2c_imx->mode == HS)
258 		writel(temp, lpi2c_imx->base + LPI2C_MCCR1);
259 	else
260 		writel(temp, lpi2c_imx->base + LPI2C_MCCR0);
261 
262 	return 0;
263 }
264 
265 static int lpi2c_imx_master_enable(struct lpi2c_imx_struct *lpi2c_imx)
266 {
267 	unsigned int temp;
268 	int ret;
269 
270 	ret = pm_runtime_resume_and_get(lpi2c_imx->adapter.dev.parent);
271 	if (ret < 0)
272 		return ret;
273 
274 	temp = MCR_RST;
275 	writel(temp, lpi2c_imx->base + LPI2C_MCR);
276 	writel(0, lpi2c_imx->base + LPI2C_MCR);
277 
278 	ret = lpi2c_imx_config(lpi2c_imx);
279 	if (ret)
280 		goto rpm_put;
281 
282 	temp = readl(lpi2c_imx->base + LPI2C_MCR);
283 	temp |= MCR_MEN;
284 	writel(temp, lpi2c_imx->base + LPI2C_MCR);
285 
286 	return 0;
287 
288 rpm_put:
289 	pm_runtime_mark_last_busy(lpi2c_imx->adapter.dev.parent);
290 	pm_runtime_put_autosuspend(lpi2c_imx->adapter.dev.parent);
291 
292 	return ret;
293 }
294 
295 static int lpi2c_imx_master_disable(struct lpi2c_imx_struct *lpi2c_imx)
296 {
297 	u32 temp;
298 
299 	temp = readl(lpi2c_imx->base + LPI2C_MCR);
300 	temp &= ~MCR_MEN;
301 	writel(temp, lpi2c_imx->base + LPI2C_MCR);
302 
303 	pm_runtime_mark_last_busy(lpi2c_imx->adapter.dev.parent);
304 	pm_runtime_put_autosuspend(lpi2c_imx->adapter.dev.parent);
305 
306 	return 0;
307 }
308 
309 static int lpi2c_imx_msg_complete(struct lpi2c_imx_struct *lpi2c_imx)
310 {
311 	unsigned long timeout;
312 
313 	timeout = wait_for_completion_timeout(&lpi2c_imx->complete, HZ);
314 
315 	return timeout ? 0 : -ETIMEDOUT;
316 }
317 
318 static int lpi2c_imx_txfifo_empty(struct lpi2c_imx_struct *lpi2c_imx)
319 {
320 	unsigned long orig_jiffies = jiffies;
321 	u32 txcnt;
322 
323 	do {
324 		txcnt = readl(lpi2c_imx->base + LPI2C_MFSR) & 0xff;
325 
326 		if (readl(lpi2c_imx->base + LPI2C_MSR) & MSR_NDF) {
327 			dev_dbg(&lpi2c_imx->adapter.dev, "NDF detected\n");
328 			return -EIO;
329 		}
330 
331 		if (time_after(jiffies, orig_jiffies + msecs_to_jiffies(500))) {
332 			dev_dbg(&lpi2c_imx->adapter.dev, "txfifo empty timeout\n");
333 			if (lpi2c_imx->adapter.bus_recovery_info)
334 				i2c_recover_bus(&lpi2c_imx->adapter);
335 			return -ETIMEDOUT;
336 		}
337 		schedule();
338 
339 	} while (txcnt);
340 
341 	return 0;
342 }
343 
344 static void lpi2c_imx_set_tx_watermark(struct lpi2c_imx_struct *lpi2c_imx)
345 {
346 	writel(lpi2c_imx->txfifosize >> 1, lpi2c_imx->base + LPI2C_MFCR);
347 }
348 
349 static void lpi2c_imx_set_rx_watermark(struct lpi2c_imx_struct *lpi2c_imx)
350 {
351 	unsigned int temp, remaining;
352 
353 	remaining = lpi2c_imx->msglen - lpi2c_imx->delivered;
354 
355 	if (remaining > (lpi2c_imx->rxfifosize >> 1))
356 		temp = lpi2c_imx->rxfifosize >> 1;
357 	else
358 		temp = 0;
359 
360 	writel(temp << 16, lpi2c_imx->base + LPI2C_MFCR);
361 }
362 
363 static void lpi2c_imx_write_txfifo(struct lpi2c_imx_struct *lpi2c_imx)
364 {
365 	unsigned int data, txcnt;
366 
367 	txcnt = readl(lpi2c_imx->base + LPI2C_MFSR) & 0xff;
368 
369 	while (txcnt < lpi2c_imx->txfifosize) {
370 		if (lpi2c_imx->delivered == lpi2c_imx->msglen)
371 			break;
372 
373 		data = lpi2c_imx->tx_buf[lpi2c_imx->delivered++];
374 		writel(data, lpi2c_imx->base + LPI2C_MTDR);
375 		txcnt++;
376 	}
377 
378 	if (lpi2c_imx->delivered < lpi2c_imx->msglen)
379 		lpi2c_imx_intctrl(lpi2c_imx, MIER_TDIE | MIER_NDIE);
380 	else
381 		complete(&lpi2c_imx->complete);
382 }
383 
384 static void lpi2c_imx_read_rxfifo(struct lpi2c_imx_struct *lpi2c_imx)
385 {
386 	unsigned int blocklen, remaining;
387 	unsigned int temp, data;
388 
389 	do {
390 		data = readl(lpi2c_imx->base + LPI2C_MRDR);
391 		if (data & MRDR_RXEMPTY)
392 			break;
393 
394 		lpi2c_imx->rx_buf[lpi2c_imx->delivered++] = data & 0xff;
395 	} while (1);
396 
397 	/*
398 	 * First byte is the length of remaining packet in the SMBus block
399 	 * data read. Add it to msgs->len.
400 	 */
401 	if (lpi2c_imx->block_data) {
402 		blocklen = lpi2c_imx->rx_buf[0];
403 		lpi2c_imx->msglen += blocklen;
404 	}
405 
406 	remaining = lpi2c_imx->msglen - lpi2c_imx->delivered;
407 
408 	if (!remaining) {
409 		complete(&lpi2c_imx->complete);
410 		return;
411 	}
412 
413 	/* not finished, still waiting for rx data */
414 	lpi2c_imx_set_rx_watermark(lpi2c_imx);
415 
416 	/* multiple receive commands */
417 	if (lpi2c_imx->block_data) {
418 		lpi2c_imx->block_data = 0;
419 		temp = remaining;
420 		temp |= (RECV_DATA << 8);
421 		writel(temp, lpi2c_imx->base + LPI2C_MTDR);
422 	} else if (!(lpi2c_imx->delivered & 0xff)) {
423 		temp = (remaining > CHUNK_DATA ? CHUNK_DATA : remaining) - 1;
424 		temp |= (RECV_DATA << 8);
425 		writel(temp, lpi2c_imx->base + LPI2C_MTDR);
426 	}
427 
428 	lpi2c_imx_intctrl(lpi2c_imx, MIER_RDIE);
429 }
430 
431 static void lpi2c_imx_write(struct lpi2c_imx_struct *lpi2c_imx,
432 			    struct i2c_msg *msgs)
433 {
434 	lpi2c_imx->tx_buf = msgs->buf;
435 	lpi2c_imx_set_tx_watermark(lpi2c_imx);
436 	lpi2c_imx_write_txfifo(lpi2c_imx);
437 }
438 
439 static void lpi2c_imx_read(struct lpi2c_imx_struct *lpi2c_imx,
440 			   struct i2c_msg *msgs)
441 {
442 	unsigned int temp;
443 
444 	lpi2c_imx->rx_buf = msgs->buf;
445 	lpi2c_imx->block_data = msgs->flags & I2C_M_RECV_LEN;
446 
447 	lpi2c_imx_set_rx_watermark(lpi2c_imx);
448 	temp = msgs->len > CHUNK_DATA ? CHUNK_DATA - 1 : msgs->len - 1;
449 	temp |= (RECV_DATA << 8);
450 	writel(temp, lpi2c_imx->base + LPI2C_MTDR);
451 
452 	lpi2c_imx_intctrl(lpi2c_imx, MIER_RDIE | MIER_NDIE);
453 }
454 
455 static int lpi2c_imx_xfer(struct i2c_adapter *adapter,
456 			  struct i2c_msg *msgs, int num)
457 {
458 	struct lpi2c_imx_struct *lpi2c_imx = i2c_get_adapdata(adapter);
459 	unsigned int temp;
460 	int i, result;
461 
462 	result = lpi2c_imx_master_enable(lpi2c_imx);
463 	if (result)
464 		return result;
465 
466 	for (i = 0; i < num; i++) {
467 		result = lpi2c_imx_start(lpi2c_imx, &msgs[i]);
468 		if (result)
469 			goto disable;
470 
471 		/* quick smbus */
472 		if (num == 1 && msgs[0].len == 0)
473 			goto stop;
474 
475 		lpi2c_imx->rx_buf = NULL;
476 		lpi2c_imx->tx_buf = NULL;
477 		lpi2c_imx->delivered = 0;
478 		lpi2c_imx->msglen = msgs[i].len;
479 		init_completion(&lpi2c_imx->complete);
480 
481 		if (msgs[i].flags & I2C_M_RD)
482 			lpi2c_imx_read(lpi2c_imx, &msgs[i]);
483 		else
484 			lpi2c_imx_write(lpi2c_imx, &msgs[i]);
485 
486 		result = lpi2c_imx_msg_complete(lpi2c_imx);
487 		if (result)
488 			goto stop;
489 
490 		if (!(msgs[i].flags & I2C_M_RD)) {
491 			result = lpi2c_imx_txfifo_empty(lpi2c_imx);
492 			if (result)
493 				goto stop;
494 		}
495 	}
496 
497 stop:
498 	lpi2c_imx_stop(lpi2c_imx);
499 
500 	temp = readl(lpi2c_imx->base + LPI2C_MSR);
501 	if ((temp & MSR_NDF) && !result)
502 		result = -EIO;
503 
504 disable:
505 	lpi2c_imx_master_disable(lpi2c_imx);
506 
507 	dev_dbg(&lpi2c_imx->adapter.dev, "<%s> exit with: %s: %d\n", __func__,
508 		(result < 0) ? "error" : "success msg",
509 		(result < 0) ? result : num);
510 
511 	return (result < 0) ? result : num;
512 }
513 
514 static irqreturn_t lpi2c_imx_isr(int irq, void *dev_id)
515 {
516 	struct lpi2c_imx_struct *lpi2c_imx = dev_id;
517 	unsigned int enabled;
518 	unsigned int temp;
519 
520 	enabled = readl(lpi2c_imx->base + LPI2C_MIER);
521 
522 	lpi2c_imx_intctrl(lpi2c_imx, 0);
523 	temp = readl(lpi2c_imx->base + LPI2C_MSR);
524 	temp &= enabled;
525 
526 	if (temp & MSR_NDF)
527 		complete(&lpi2c_imx->complete);
528 	else if (temp & MSR_RDF)
529 		lpi2c_imx_read_rxfifo(lpi2c_imx);
530 	else if (temp & MSR_TDF)
531 		lpi2c_imx_write_txfifo(lpi2c_imx);
532 
533 	return IRQ_HANDLED;
534 }
535 
536 static int lpi2c_imx_init_recovery_info(struct lpi2c_imx_struct *lpi2c_imx,
537 				  struct platform_device *pdev)
538 {
539 	struct i2c_bus_recovery_info *bri = &lpi2c_imx->rinfo;
540 
541 	bri->pinctrl = devm_pinctrl_get(&pdev->dev);
542 	if (IS_ERR(bri->pinctrl))
543 		return PTR_ERR(bri->pinctrl);
544 
545 	lpi2c_imx->adapter.bus_recovery_info = bri;
546 
547 	return 0;
548 }
549 
550 static u32 lpi2c_imx_func(struct i2c_adapter *adapter)
551 {
552 	return I2C_FUNC_I2C | I2C_FUNC_SMBUS_EMUL |
553 		I2C_FUNC_SMBUS_READ_BLOCK_DATA;
554 }
555 
556 static const struct i2c_algorithm lpi2c_imx_algo = {
557 	.master_xfer	= lpi2c_imx_xfer,
558 	.functionality	= lpi2c_imx_func,
559 };
560 
561 static const struct of_device_id lpi2c_imx_of_match[] = {
562 	{ .compatible = "fsl,imx7ulp-lpi2c" },
563 	{ },
564 };
565 MODULE_DEVICE_TABLE(of, lpi2c_imx_of_match);
566 
567 static int lpi2c_imx_probe(struct platform_device *pdev)
568 {
569 	struct lpi2c_imx_struct *lpi2c_imx;
570 	unsigned int temp;
571 	int irq, ret;
572 
573 	lpi2c_imx = devm_kzalloc(&pdev->dev, sizeof(*lpi2c_imx), GFP_KERNEL);
574 	if (!lpi2c_imx)
575 		return -ENOMEM;
576 
577 	lpi2c_imx->base = devm_platform_ioremap_resource(pdev, 0);
578 	if (IS_ERR(lpi2c_imx->base))
579 		return PTR_ERR(lpi2c_imx->base);
580 
581 	irq = platform_get_irq(pdev, 0);
582 	if (irq < 0)
583 		return irq;
584 
585 	lpi2c_imx->adapter.owner	= THIS_MODULE;
586 	lpi2c_imx->adapter.algo		= &lpi2c_imx_algo;
587 	lpi2c_imx->adapter.dev.parent	= &pdev->dev;
588 	lpi2c_imx->adapter.dev.of_node	= pdev->dev.of_node;
589 	strscpy(lpi2c_imx->adapter.name, pdev->name,
590 		sizeof(lpi2c_imx->adapter.name));
591 
592 	ret = devm_clk_bulk_get_all(&pdev->dev, &lpi2c_imx->clks);
593 	if (ret < 0)
594 		return dev_err_probe(&pdev->dev, ret, "can't get I2C peripheral clock\n");
595 	lpi2c_imx->num_clks = ret;
596 
597 	ret = of_property_read_u32(pdev->dev.of_node,
598 				   "clock-frequency", &lpi2c_imx->bitrate);
599 	if (ret)
600 		lpi2c_imx->bitrate = I2C_MAX_STANDARD_MODE_FREQ;
601 
602 	ret = devm_request_irq(&pdev->dev, irq, lpi2c_imx_isr, 0,
603 			       pdev->name, lpi2c_imx);
604 	if (ret)
605 		return dev_err_probe(&pdev->dev, ret, "can't claim irq %d\n", irq);
606 
607 	i2c_set_adapdata(&lpi2c_imx->adapter, lpi2c_imx);
608 	platform_set_drvdata(pdev, lpi2c_imx);
609 
610 	ret = clk_bulk_prepare_enable(lpi2c_imx->num_clks, lpi2c_imx->clks);
611 	if (ret)
612 		return ret;
613 
614 	pm_runtime_set_autosuspend_delay(&pdev->dev, I2C_PM_TIMEOUT);
615 	pm_runtime_use_autosuspend(&pdev->dev);
616 	pm_runtime_get_noresume(&pdev->dev);
617 	pm_runtime_set_active(&pdev->dev);
618 	pm_runtime_enable(&pdev->dev);
619 
620 	temp = readl(lpi2c_imx->base + LPI2C_PARAM);
621 	lpi2c_imx->txfifosize = 1 << (temp & 0x0f);
622 	lpi2c_imx->rxfifosize = 1 << ((temp >> 8) & 0x0f);
623 
624 	/* Init optional bus recovery function */
625 	ret = lpi2c_imx_init_recovery_info(lpi2c_imx, pdev);
626 	/* Give it another chance if pinctrl used is not ready yet */
627 	if (ret == -EPROBE_DEFER)
628 		goto rpm_disable;
629 
630 	ret = i2c_add_adapter(&lpi2c_imx->adapter);
631 	if (ret)
632 		goto rpm_disable;
633 
634 	pm_runtime_mark_last_busy(&pdev->dev);
635 	pm_runtime_put_autosuspend(&pdev->dev);
636 
637 	dev_info(&lpi2c_imx->adapter.dev, "LPI2C adapter registered\n");
638 
639 	return 0;
640 
641 rpm_disable:
642 	pm_runtime_put(&pdev->dev);
643 	pm_runtime_disable(&pdev->dev);
644 	pm_runtime_dont_use_autosuspend(&pdev->dev);
645 
646 	return ret;
647 }
648 
649 static void lpi2c_imx_remove(struct platform_device *pdev)
650 {
651 	struct lpi2c_imx_struct *lpi2c_imx = platform_get_drvdata(pdev);
652 
653 	i2c_del_adapter(&lpi2c_imx->adapter);
654 
655 	pm_runtime_disable(&pdev->dev);
656 	pm_runtime_dont_use_autosuspend(&pdev->dev);
657 }
658 
659 static int __maybe_unused lpi2c_runtime_suspend(struct device *dev)
660 {
661 	struct lpi2c_imx_struct *lpi2c_imx = dev_get_drvdata(dev);
662 
663 	clk_bulk_disable(lpi2c_imx->num_clks, lpi2c_imx->clks);
664 	pinctrl_pm_select_sleep_state(dev);
665 
666 	return 0;
667 }
668 
669 static int __maybe_unused lpi2c_runtime_resume(struct device *dev)
670 {
671 	struct lpi2c_imx_struct *lpi2c_imx = dev_get_drvdata(dev);
672 	int ret;
673 
674 	pinctrl_pm_select_default_state(dev);
675 	ret = clk_bulk_enable(lpi2c_imx->num_clks, lpi2c_imx->clks);
676 	if (ret) {
677 		dev_err(dev, "failed to enable I2C clock, ret=%d\n", ret);
678 		return ret;
679 	}
680 
681 	return 0;
682 }
683 
684 static const struct dev_pm_ops lpi2c_pm_ops = {
685 	SET_NOIRQ_SYSTEM_SLEEP_PM_OPS(pm_runtime_force_suspend,
686 				      pm_runtime_force_resume)
687 	SET_RUNTIME_PM_OPS(lpi2c_runtime_suspend,
688 			   lpi2c_runtime_resume, NULL)
689 };
690 
691 static struct platform_driver lpi2c_imx_driver = {
692 	.probe = lpi2c_imx_probe,
693 	.remove_new = lpi2c_imx_remove,
694 	.driver = {
695 		.name = DRIVER_NAME,
696 		.of_match_table = lpi2c_imx_of_match,
697 		.pm = &lpi2c_pm_ops,
698 	},
699 };
700 
701 module_platform_driver(lpi2c_imx_driver);
702 
703 MODULE_AUTHOR("Gao Pan <pandy.gao@nxp.com>");
704 MODULE_DESCRIPTION("I2C adapter driver for LPI2C bus");
705 MODULE_LICENSE("GPL");
706