xref: /linux/drivers/i2c/busses/i2c-imx-lpi2c.c (revision 1c9f8dff62d85ce00b0e99f774a84bd783af7cac)
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/of_device.h>
21 #include <linux/pinctrl/consumer.h>
22 #include <linux/platform_device.h>
23 #include <linux/pm_runtime.h>
24 #include <linux/sched.h>
25 #include <linux/slab.h>
26 
27 #define DRIVER_NAME "imx-lpi2c"
28 
29 #define LPI2C_PARAM	0x04	/* i2c RX/TX FIFO size */
30 #define LPI2C_MCR	0x10	/* i2c contrl register */
31 #define LPI2C_MSR	0x14	/* i2c status register */
32 #define LPI2C_MIER	0x18	/* i2c interrupt enable */
33 #define LPI2C_MCFGR0	0x20	/* i2c master configuration */
34 #define LPI2C_MCFGR1	0x24	/* i2c master configuration */
35 #define LPI2C_MCFGR2	0x28	/* i2c master configuration */
36 #define LPI2C_MCFGR3	0x2C	/* i2c master configuration */
37 #define LPI2C_MCCR0	0x48	/* i2c master clk configuration */
38 #define LPI2C_MCCR1	0x50	/* i2c master clk configuration */
39 #define LPI2C_MFCR	0x58	/* i2c master FIFO control */
40 #define LPI2C_MFSR	0x5C	/* i2c master FIFO status */
41 #define LPI2C_MTDR	0x60	/* i2c master TX data register */
42 #define LPI2C_MRDR	0x70	/* i2c master RX data register */
43 
44 /* i2c command */
45 #define TRAN_DATA	0X00
46 #define RECV_DATA	0X01
47 #define GEN_STOP	0X02
48 #define RECV_DISCARD	0X03
49 #define GEN_START	0X04
50 #define START_NACK	0X05
51 #define START_HIGH	0X06
52 #define START_HIGH_NACK	0X07
53 
54 #define MCR_MEN		BIT(0)
55 #define MCR_RST		BIT(1)
56 #define MCR_DOZEN	BIT(2)
57 #define MCR_DBGEN	BIT(3)
58 #define MCR_RTF		BIT(8)
59 #define MCR_RRF		BIT(9)
60 #define MSR_TDF		BIT(0)
61 #define MSR_RDF		BIT(1)
62 #define MSR_SDF		BIT(9)
63 #define MSR_NDF		BIT(10)
64 #define MSR_ALF		BIT(11)
65 #define MSR_MBF		BIT(24)
66 #define MSR_BBF		BIT(25)
67 #define MIER_TDIE	BIT(0)
68 #define MIER_RDIE	BIT(1)
69 #define MIER_SDIE	BIT(9)
70 #define MIER_NDIE	BIT(10)
71 #define MCFGR1_AUTOSTOP	BIT(8)
72 #define MCFGR1_IGNACK	BIT(9)
73 #define MRDR_RXEMPTY	BIT(14)
74 
75 #define I2C_CLK_RATIO	2
76 #define CHUNK_DATA	256
77 
78 #define I2C_PM_TIMEOUT		10 /* ms */
79 
80 enum lpi2c_imx_mode {
81 	STANDARD,	/* 100+Kbps */
82 	FAST,		/* 400+Kbps */
83 	FAST_PLUS,	/* 1.0+Mbps */
84 	HS,		/* 3.4+Mbps */
85 	ULTRA_FAST,	/* 5.0+Mbps */
86 };
87 
88 enum lpi2c_imx_pincfg {
89 	TWO_PIN_OD,
90 	TWO_PIN_OO,
91 	TWO_PIN_PP,
92 	FOUR_PIN_PP,
93 };
94 
95 struct lpi2c_imx_struct {
96 	struct i2c_adapter	adapter;
97 	int			num_clks;
98 	struct clk_bulk_data	*clks;
99 	void __iomem		*base;
100 	__u8			*rx_buf;
101 	__u8			*tx_buf;
102 	struct completion	complete;
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 };
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 			return -ETIMEDOUT;
138 		}
139 		schedule();
140 	}
141 
142 	return 0;
143 }
144 
145 static void lpi2c_imx_set_mode(struct lpi2c_imx_struct *lpi2c_imx)
146 {
147 	unsigned int bitrate = lpi2c_imx->bitrate;
148 	enum lpi2c_imx_mode mode;
149 
150 	if (bitrate < I2C_MAX_FAST_MODE_FREQ)
151 		mode = STANDARD;
152 	else if (bitrate < I2C_MAX_FAST_MODE_PLUS_FREQ)
153 		mode = FAST;
154 	else if (bitrate < I2C_MAX_HIGH_SPEED_MODE_FREQ)
155 		mode = FAST_PLUS;
156 	else if (bitrate < I2C_MAX_ULTRA_FAST_MODE_FREQ)
157 		mode = HS;
158 	else
159 		mode = ULTRA_FAST;
160 
161 	lpi2c_imx->mode = mode;
162 }
163 
164 static int lpi2c_imx_start(struct lpi2c_imx_struct *lpi2c_imx,
165 			   struct i2c_msg *msgs)
166 {
167 	unsigned int temp;
168 
169 	temp = readl(lpi2c_imx->base + LPI2C_MCR);
170 	temp |= MCR_RRF | MCR_RTF;
171 	writel(temp, lpi2c_imx->base + LPI2C_MCR);
172 	writel(0x7f00, lpi2c_imx->base + LPI2C_MSR);
173 
174 	temp = i2c_8bit_addr_from_msg(msgs) | (GEN_START << 8);
175 	writel(temp, lpi2c_imx->base + LPI2C_MTDR);
176 
177 	return lpi2c_imx_bus_busy(lpi2c_imx);
178 }
179 
180 static void lpi2c_imx_stop(struct lpi2c_imx_struct *lpi2c_imx)
181 {
182 	unsigned long orig_jiffies = jiffies;
183 	unsigned int temp;
184 
185 	writel(GEN_STOP << 8, lpi2c_imx->base + LPI2C_MTDR);
186 
187 	do {
188 		temp = readl(lpi2c_imx->base + LPI2C_MSR);
189 		if (temp & MSR_SDF)
190 			break;
191 
192 		if (time_after(jiffies, orig_jiffies + msecs_to_jiffies(500))) {
193 			dev_dbg(&lpi2c_imx->adapter.dev, "stop timeout\n");
194 			break;
195 		}
196 		schedule();
197 
198 	} while (1);
199 }
200 
201 /* CLKLO = I2C_CLK_RATIO * CLKHI, SETHOLD = CLKHI, DATAVD = CLKHI/2 */
202 static int lpi2c_imx_config(struct lpi2c_imx_struct *lpi2c_imx)
203 {
204 	u8 prescale, filt, sethold, datavd;
205 	unsigned int clk_rate, clk_cycle, clkhi, clklo;
206 	enum lpi2c_imx_pincfg pincfg;
207 	unsigned int temp;
208 
209 	lpi2c_imx_set_mode(lpi2c_imx);
210 
211 	clk_rate = clk_get_rate(lpi2c_imx->clks[0].clk);
212 	if (!clk_rate)
213 		return -EINVAL;
214 
215 	if (lpi2c_imx->mode == HS || lpi2c_imx->mode == ULTRA_FAST)
216 		filt = 0;
217 	else
218 		filt = 2;
219 
220 	for (prescale = 0; prescale <= 7; prescale++) {
221 		clk_cycle = clk_rate / ((1 << prescale) * lpi2c_imx->bitrate)
222 			    - 3 - (filt >> 1);
223 		clkhi = DIV_ROUND_UP(clk_cycle, I2C_CLK_RATIO + 1);
224 		clklo = clk_cycle - clkhi;
225 		if (clklo < 64)
226 			break;
227 	}
228 
229 	if (prescale > 7)
230 		return -EINVAL;
231 
232 	/* set MCFGR1: PINCFG, PRESCALE, IGNACK */
233 	if (lpi2c_imx->mode == ULTRA_FAST)
234 		pincfg = TWO_PIN_OO;
235 	else
236 		pincfg = TWO_PIN_OD;
237 	temp = prescale | pincfg << 24;
238 
239 	if (lpi2c_imx->mode == ULTRA_FAST)
240 		temp |= MCFGR1_IGNACK;
241 
242 	writel(temp, lpi2c_imx->base + LPI2C_MCFGR1);
243 
244 	/* set MCFGR2: FILTSDA, FILTSCL */
245 	temp = (filt << 16) | (filt << 24);
246 	writel(temp, lpi2c_imx->base + LPI2C_MCFGR2);
247 
248 	/* set MCCR: DATAVD, SETHOLD, CLKHI, CLKLO */
249 	sethold = clkhi;
250 	datavd = clkhi >> 1;
251 	temp = datavd << 24 | sethold << 16 | clkhi << 8 | clklo;
252 
253 	if (lpi2c_imx->mode == HS)
254 		writel(temp, lpi2c_imx->base + LPI2C_MCCR1);
255 	else
256 		writel(temp, lpi2c_imx->base + LPI2C_MCCR0);
257 
258 	return 0;
259 }
260 
261 static int lpi2c_imx_master_enable(struct lpi2c_imx_struct *lpi2c_imx)
262 {
263 	unsigned int temp;
264 	int ret;
265 
266 	ret = pm_runtime_resume_and_get(lpi2c_imx->adapter.dev.parent);
267 	if (ret < 0)
268 		return ret;
269 
270 	temp = MCR_RST;
271 	writel(temp, lpi2c_imx->base + LPI2C_MCR);
272 	writel(0, lpi2c_imx->base + LPI2C_MCR);
273 
274 	ret = lpi2c_imx_config(lpi2c_imx);
275 	if (ret)
276 		goto rpm_put;
277 
278 	temp = readl(lpi2c_imx->base + LPI2C_MCR);
279 	temp |= MCR_MEN;
280 	writel(temp, lpi2c_imx->base + LPI2C_MCR);
281 
282 	return 0;
283 
284 rpm_put:
285 	pm_runtime_mark_last_busy(lpi2c_imx->adapter.dev.parent);
286 	pm_runtime_put_autosuspend(lpi2c_imx->adapter.dev.parent);
287 
288 	return ret;
289 }
290 
291 static int lpi2c_imx_master_disable(struct lpi2c_imx_struct *lpi2c_imx)
292 {
293 	u32 temp;
294 
295 	temp = readl(lpi2c_imx->base + LPI2C_MCR);
296 	temp &= ~MCR_MEN;
297 	writel(temp, lpi2c_imx->base + LPI2C_MCR);
298 
299 	pm_runtime_mark_last_busy(lpi2c_imx->adapter.dev.parent);
300 	pm_runtime_put_autosuspend(lpi2c_imx->adapter.dev.parent);
301 
302 	return 0;
303 }
304 
305 static int lpi2c_imx_msg_complete(struct lpi2c_imx_struct *lpi2c_imx)
306 {
307 	unsigned long timeout;
308 
309 	timeout = wait_for_completion_timeout(&lpi2c_imx->complete, HZ);
310 
311 	return timeout ? 0 : -ETIMEDOUT;
312 }
313 
314 static int lpi2c_imx_txfifo_empty(struct lpi2c_imx_struct *lpi2c_imx)
315 {
316 	unsigned long orig_jiffies = jiffies;
317 	u32 txcnt;
318 
319 	do {
320 		txcnt = readl(lpi2c_imx->base + LPI2C_MFSR) & 0xff;
321 
322 		if (readl(lpi2c_imx->base + LPI2C_MSR) & MSR_NDF) {
323 			dev_dbg(&lpi2c_imx->adapter.dev, "NDF detected\n");
324 			return -EIO;
325 		}
326 
327 		if (time_after(jiffies, orig_jiffies + msecs_to_jiffies(500))) {
328 			dev_dbg(&lpi2c_imx->adapter.dev, "txfifo empty timeout\n");
329 			return -ETIMEDOUT;
330 		}
331 		schedule();
332 
333 	} while (txcnt);
334 
335 	return 0;
336 }
337 
338 static void lpi2c_imx_set_tx_watermark(struct lpi2c_imx_struct *lpi2c_imx)
339 {
340 	writel(lpi2c_imx->txfifosize >> 1, lpi2c_imx->base + LPI2C_MFCR);
341 }
342 
343 static void lpi2c_imx_set_rx_watermark(struct lpi2c_imx_struct *lpi2c_imx)
344 {
345 	unsigned int temp, remaining;
346 
347 	remaining = lpi2c_imx->msglen - lpi2c_imx->delivered;
348 
349 	if (remaining > (lpi2c_imx->rxfifosize >> 1))
350 		temp = lpi2c_imx->rxfifosize >> 1;
351 	else
352 		temp = 0;
353 
354 	writel(temp << 16, lpi2c_imx->base + LPI2C_MFCR);
355 }
356 
357 static void lpi2c_imx_write_txfifo(struct lpi2c_imx_struct *lpi2c_imx)
358 {
359 	unsigned int data, txcnt;
360 
361 	txcnt = readl(lpi2c_imx->base + LPI2C_MFSR) & 0xff;
362 
363 	while (txcnt < lpi2c_imx->txfifosize) {
364 		if (lpi2c_imx->delivered == lpi2c_imx->msglen)
365 			break;
366 
367 		data = lpi2c_imx->tx_buf[lpi2c_imx->delivered++];
368 		writel(data, lpi2c_imx->base + LPI2C_MTDR);
369 		txcnt++;
370 	}
371 
372 	if (lpi2c_imx->delivered < lpi2c_imx->msglen)
373 		lpi2c_imx_intctrl(lpi2c_imx, MIER_TDIE | MIER_NDIE);
374 	else
375 		complete(&lpi2c_imx->complete);
376 }
377 
378 static void lpi2c_imx_read_rxfifo(struct lpi2c_imx_struct *lpi2c_imx)
379 {
380 	unsigned int blocklen, remaining;
381 	unsigned int temp, data;
382 
383 	do {
384 		data = readl(lpi2c_imx->base + LPI2C_MRDR);
385 		if (data & MRDR_RXEMPTY)
386 			break;
387 
388 		lpi2c_imx->rx_buf[lpi2c_imx->delivered++] = data & 0xff;
389 	} while (1);
390 
391 	/*
392 	 * First byte is the length of remaining packet in the SMBus block
393 	 * data read. Add it to msgs->len.
394 	 */
395 	if (lpi2c_imx->block_data) {
396 		blocklen = lpi2c_imx->rx_buf[0];
397 		lpi2c_imx->msglen += blocklen;
398 	}
399 
400 	remaining = lpi2c_imx->msglen - lpi2c_imx->delivered;
401 
402 	if (!remaining) {
403 		complete(&lpi2c_imx->complete);
404 		return;
405 	}
406 
407 	/* not finished, still waiting for rx data */
408 	lpi2c_imx_set_rx_watermark(lpi2c_imx);
409 
410 	/* multiple receive commands */
411 	if (lpi2c_imx->block_data) {
412 		lpi2c_imx->block_data = 0;
413 		temp = remaining;
414 		temp |= (RECV_DATA << 8);
415 		writel(temp, lpi2c_imx->base + LPI2C_MTDR);
416 	} else if (!(lpi2c_imx->delivered & 0xff)) {
417 		temp = (remaining > CHUNK_DATA ? CHUNK_DATA : remaining) - 1;
418 		temp |= (RECV_DATA << 8);
419 		writel(temp, lpi2c_imx->base + LPI2C_MTDR);
420 	}
421 
422 	lpi2c_imx_intctrl(lpi2c_imx, MIER_RDIE);
423 }
424 
425 static void lpi2c_imx_write(struct lpi2c_imx_struct *lpi2c_imx,
426 			    struct i2c_msg *msgs)
427 {
428 	lpi2c_imx->tx_buf = msgs->buf;
429 	lpi2c_imx_set_tx_watermark(lpi2c_imx);
430 	lpi2c_imx_write_txfifo(lpi2c_imx);
431 }
432 
433 static void lpi2c_imx_read(struct lpi2c_imx_struct *lpi2c_imx,
434 			   struct i2c_msg *msgs)
435 {
436 	unsigned int temp;
437 
438 	lpi2c_imx->rx_buf = msgs->buf;
439 	lpi2c_imx->block_data = msgs->flags & I2C_M_RECV_LEN;
440 
441 	lpi2c_imx_set_rx_watermark(lpi2c_imx);
442 	temp = msgs->len > CHUNK_DATA ? CHUNK_DATA - 1 : msgs->len - 1;
443 	temp |= (RECV_DATA << 8);
444 	writel(temp, lpi2c_imx->base + LPI2C_MTDR);
445 
446 	lpi2c_imx_intctrl(lpi2c_imx, MIER_RDIE | MIER_NDIE);
447 }
448 
449 static int lpi2c_imx_xfer(struct i2c_adapter *adapter,
450 			  struct i2c_msg *msgs, int num)
451 {
452 	struct lpi2c_imx_struct *lpi2c_imx = i2c_get_adapdata(adapter);
453 	unsigned int temp;
454 	int i, result;
455 
456 	result = lpi2c_imx_master_enable(lpi2c_imx);
457 	if (result)
458 		return result;
459 
460 	for (i = 0; i < num; i++) {
461 		result = lpi2c_imx_start(lpi2c_imx, &msgs[i]);
462 		if (result)
463 			goto disable;
464 
465 		/* quick smbus */
466 		if (num == 1 && msgs[0].len == 0)
467 			goto stop;
468 
469 		lpi2c_imx->rx_buf = NULL;
470 		lpi2c_imx->tx_buf = NULL;
471 		lpi2c_imx->delivered = 0;
472 		lpi2c_imx->msglen = msgs[i].len;
473 		init_completion(&lpi2c_imx->complete);
474 
475 		if (msgs[i].flags & I2C_M_RD)
476 			lpi2c_imx_read(lpi2c_imx, &msgs[i]);
477 		else
478 			lpi2c_imx_write(lpi2c_imx, &msgs[i]);
479 
480 		result = lpi2c_imx_msg_complete(lpi2c_imx);
481 		if (result)
482 			goto stop;
483 
484 		if (!(msgs[i].flags & I2C_M_RD)) {
485 			result = lpi2c_imx_txfifo_empty(lpi2c_imx);
486 			if (result)
487 				goto stop;
488 		}
489 	}
490 
491 stop:
492 	lpi2c_imx_stop(lpi2c_imx);
493 
494 	temp = readl(lpi2c_imx->base + LPI2C_MSR);
495 	if ((temp & MSR_NDF) && !result)
496 		result = -EIO;
497 
498 disable:
499 	lpi2c_imx_master_disable(lpi2c_imx);
500 
501 	dev_dbg(&lpi2c_imx->adapter.dev, "<%s> exit with: %s: %d\n", __func__,
502 		(result < 0) ? "error" : "success msg",
503 		(result < 0) ? result : num);
504 
505 	return (result < 0) ? result : num;
506 }
507 
508 static irqreturn_t lpi2c_imx_isr(int irq, void *dev_id)
509 {
510 	struct lpi2c_imx_struct *lpi2c_imx = dev_id;
511 	unsigned int enabled;
512 	unsigned int temp;
513 
514 	enabled = readl(lpi2c_imx->base + LPI2C_MIER);
515 
516 	lpi2c_imx_intctrl(lpi2c_imx, 0);
517 	temp = readl(lpi2c_imx->base + LPI2C_MSR);
518 	temp &= enabled;
519 
520 	if (temp & MSR_RDF)
521 		lpi2c_imx_read_rxfifo(lpi2c_imx);
522 
523 	if (temp & MSR_TDF)
524 		lpi2c_imx_write_txfifo(lpi2c_imx);
525 
526 	if (temp & MSR_NDF)
527 		complete(&lpi2c_imx->complete);
528 
529 	return IRQ_HANDLED;
530 }
531 
532 static u32 lpi2c_imx_func(struct i2c_adapter *adapter)
533 {
534 	return I2C_FUNC_I2C | I2C_FUNC_SMBUS_EMUL |
535 		I2C_FUNC_SMBUS_READ_BLOCK_DATA;
536 }
537 
538 static const struct i2c_algorithm lpi2c_imx_algo = {
539 	.master_xfer	= lpi2c_imx_xfer,
540 	.functionality	= lpi2c_imx_func,
541 };
542 
543 static const struct of_device_id lpi2c_imx_of_match[] = {
544 	{ .compatible = "fsl,imx7ulp-lpi2c" },
545 	{ },
546 };
547 MODULE_DEVICE_TABLE(of, lpi2c_imx_of_match);
548 
549 static int lpi2c_imx_probe(struct platform_device *pdev)
550 {
551 	struct lpi2c_imx_struct *lpi2c_imx;
552 	unsigned int temp;
553 	int irq, ret;
554 
555 	lpi2c_imx = devm_kzalloc(&pdev->dev, sizeof(*lpi2c_imx), GFP_KERNEL);
556 	if (!lpi2c_imx)
557 		return -ENOMEM;
558 
559 	lpi2c_imx->base = devm_platform_ioremap_resource(pdev, 0);
560 	if (IS_ERR(lpi2c_imx->base))
561 		return PTR_ERR(lpi2c_imx->base);
562 
563 	irq = platform_get_irq(pdev, 0);
564 	if (irq < 0)
565 		return irq;
566 
567 	lpi2c_imx->adapter.owner	= THIS_MODULE;
568 	lpi2c_imx->adapter.algo		= &lpi2c_imx_algo;
569 	lpi2c_imx->adapter.dev.parent	= &pdev->dev;
570 	lpi2c_imx->adapter.dev.of_node	= pdev->dev.of_node;
571 	strscpy(lpi2c_imx->adapter.name, pdev->name,
572 		sizeof(lpi2c_imx->adapter.name));
573 
574 	ret = devm_clk_bulk_get_all(&pdev->dev, &lpi2c_imx->clks);
575 	if (ret < 0) {
576 		dev_err(&pdev->dev, "can't get I2C peripheral clock, ret=%d\n", ret);
577 		return ret;
578 	}
579 	lpi2c_imx->num_clks = ret;
580 
581 	ret = of_property_read_u32(pdev->dev.of_node,
582 				   "clock-frequency", &lpi2c_imx->bitrate);
583 	if (ret)
584 		lpi2c_imx->bitrate = I2C_MAX_STANDARD_MODE_FREQ;
585 
586 	ret = devm_request_irq(&pdev->dev, irq, lpi2c_imx_isr, 0,
587 			       pdev->name, lpi2c_imx);
588 	if (ret) {
589 		dev_err(&pdev->dev, "can't claim irq %d\n", irq);
590 		return ret;
591 	}
592 
593 	i2c_set_adapdata(&lpi2c_imx->adapter, lpi2c_imx);
594 	platform_set_drvdata(pdev, lpi2c_imx);
595 
596 	ret = clk_bulk_prepare_enable(lpi2c_imx->num_clks, lpi2c_imx->clks);
597 	if (ret)
598 		return ret;
599 
600 	pm_runtime_set_autosuspend_delay(&pdev->dev, I2C_PM_TIMEOUT);
601 	pm_runtime_use_autosuspend(&pdev->dev);
602 	pm_runtime_get_noresume(&pdev->dev);
603 	pm_runtime_set_active(&pdev->dev);
604 	pm_runtime_enable(&pdev->dev);
605 
606 	temp = readl(lpi2c_imx->base + LPI2C_PARAM);
607 	lpi2c_imx->txfifosize = 1 << (temp & 0x0f);
608 	lpi2c_imx->rxfifosize = 1 << ((temp >> 8) & 0x0f);
609 
610 	ret = i2c_add_adapter(&lpi2c_imx->adapter);
611 	if (ret)
612 		goto rpm_disable;
613 
614 	pm_runtime_mark_last_busy(&pdev->dev);
615 	pm_runtime_put_autosuspend(&pdev->dev);
616 
617 	dev_info(&lpi2c_imx->adapter.dev, "LPI2C adapter registered\n");
618 
619 	return 0;
620 
621 rpm_disable:
622 	pm_runtime_put(&pdev->dev);
623 	pm_runtime_disable(&pdev->dev);
624 	pm_runtime_dont_use_autosuspend(&pdev->dev);
625 
626 	return ret;
627 }
628 
629 static void lpi2c_imx_remove(struct platform_device *pdev)
630 {
631 	struct lpi2c_imx_struct *lpi2c_imx = platform_get_drvdata(pdev);
632 
633 	i2c_del_adapter(&lpi2c_imx->adapter);
634 
635 	pm_runtime_disable(&pdev->dev);
636 	pm_runtime_dont_use_autosuspend(&pdev->dev);
637 }
638 
639 static int __maybe_unused lpi2c_runtime_suspend(struct device *dev)
640 {
641 	struct lpi2c_imx_struct *lpi2c_imx = dev_get_drvdata(dev);
642 
643 	clk_bulk_disable(lpi2c_imx->num_clks, lpi2c_imx->clks);
644 	pinctrl_pm_select_sleep_state(dev);
645 
646 	return 0;
647 }
648 
649 static int __maybe_unused lpi2c_runtime_resume(struct device *dev)
650 {
651 	struct lpi2c_imx_struct *lpi2c_imx = dev_get_drvdata(dev);
652 	int ret;
653 
654 	pinctrl_pm_select_default_state(dev);
655 	ret = clk_bulk_enable(lpi2c_imx->num_clks, lpi2c_imx->clks);
656 	if (ret) {
657 		dev_err(dev, "failed to enable I2C clock, ret=%d\n", ret);
658 		return ret;
659 	}
660 
661 	return 0;
662 }
663 
664 static const struct dev_pm_ops lpi2c_pm_ops = {
665 	SET_NOIRQ_SYSTEM_SLEEP_PM_OPS(pm_runtime_force_suspend,
666 				      pm_runtime_force_resume)
667 	SET_RUNTIME_PM_OPS(lpi2c_runtime_suspend,
668 			   lpi2c_runtime_resume, NULL)
669 };
670 
671 static struct platform_driver lpi2c_imx_driver = {
672 	.probe = lpi2c_imx_probe,
673 	.remove_new = lpi2c_imx_remove,
674 	.driver = {
675 		.name = DRIVER_NAME,
676 		.of_match_table = lpi2c_imx_of_match,
677 		.pm = &lpi2c_pm_ops,
678 	},
679 };
680 
681 module_platform_driver(lpi2c_imx_driver);
682 
683 MODULE_AUTHOR("Gao Pan <pandy.gao@nxp.com>");
684 MODULE_DESCRIPTION("I2C adapter driver for LPI2C bus");
685 MODULE_LICENSE("GPL");
686