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