xref: /linux/drivers/i2c/busses/i2c-imx-lpi2c.c (revision 90d32e92011eaae8e70a9169b4e7acf4ca8f9d3a)
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 
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 
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 
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 
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 
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 */
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 
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 
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 
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 
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 
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 
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 
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 
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 
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 
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 
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 
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 
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 
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 
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 
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 
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 
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