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  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
 79enum 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
 87enum lpi2c_imx_pincfg {
 88	TWO_PIN_OD,
 89	TWO_PIN_OO,
 90	TWO_PIN_PP,
 91	FOUR_PIN_PP,
 92};
 93
 94struct 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
113static 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
119static 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
148static 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
167static 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
183static 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 */
207static 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
264static 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
287rpm_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
294static 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
308static 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
317static 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
343static 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
348static 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
362static 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
383static 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
430static 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
438static 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
454static 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
496stop:
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
503disable:
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
513static 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
535static 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
549static 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
555static const struct i2c_algorithm lpi2c_imx_algo = {
556	.master_xfer	= lpi2c_imx_xfer,
557	.functionality	= lpi2c_imx_func,
558};
559
560static const struct of_device_id lpi2c_imx_of_match[] = {
561	{ .compatible = "fsl,imx7ulp-lpi2c" },
562	{ }
563};
564MODULE_DEVICE_TABLE(of, lpi2c_imx_of_match);
565
566static 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
654rpm_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
662static 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
672static 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
682static 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
697static 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
704static struct platform_driver lpi2c_imx_driver = {
705	.probe = lpi2c_imx_probe,
706	.remove = 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
714module_platform_driver(lpi2c_imx_driver);
715
716MODULE_AUTHOR("Gao Pan <pandy.gao@nxp.com>");
717MODULE_DESCRIPTION("I2C adapter driver for LPI2C bus");
718MODULE_LICENSE("GPL");