1/*
2 * Driver for the Renesas RCar I2C unit
3 *
4 * Copyright (C) 2014 Wolfram Sang <wsa@sang-engineering.com>
5 *
6 * Copyright (C) 2012-14 Renesas Solutions Corp.
7 * Kuninori Morimoto <kuninori.morimoto.gx@renesas.com>
8 *
9 * This file is based on the drivers/i2c/busses/i2c-sh7760.c
10 * (c) 2005-2008 MSC Vertriebsges.m.b.H, Manuel Lauss <mlau@msc-ge.com>
11 *
12 * This file used out-of-tree driver i2c-rcar.c
13 * Copyright (C) 2011-2012 Renesas Electronics Corporation
14 *
15 * This program is free software; you can redistribute it and/or modify
16 * it under the terms of the GNU General Public License as published by
17 * the Free Software Foundation; version 2 of the License.
18 *
19 * This program is distributed in the hope that it will be useful,
20 * but WITHOUT ANY WARRANTY; without even the implied warranty of
21 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
22 * GNU General Public License for more details.
23 */
24#include <linux/clk.h>
25#include <linux/delay.h>
26#include <linux/err.h>
27#include <linux/interrupt.h>
28#include <linux/io.h>
29#include <linux/i2c.h>
30#include <linux/kernel.h>
31#include <linux/module.h>
32#include <linux/of_device.h>
33#include <linux/platform_device.h>
34#include <linux/pm_runtime.h>
35#include <linux/slab.h>
36#include <linux/spinlock.h>
37
38/* register offsets */
39#define ICSCR	0x00	/* slave ctrl */
40#define ICMCR	0x04	/* master ctrl */
41#define ICSSR	0x08	/* slave status */
42#define ICMSR	0x0C	/* master status */
43#define ICSIER	0x10	/* slave irq enable */
44#define ICMIER	0x14	/* master irq enable */
45#define ICCCR	0x18	/* clock dividers */
46#define ICSAR	0x1C	/* slave address */
47#define ICMAR	0x20	/* master address */
48#define ICRXTX	0x24	/* data port */
49
50/* ICSCR */
51#define SDBS	(1 << 3)	/* slave data buffer select */
52#define SIE	(1 << 2)	/* slave interface enable */
53#define GCAE	(1 << 1)	/* general call address enable */
54#define FNA	(1 << 0)	/* forced non acknowledgment */
55
56/* ICMCR */
57#define MDBS	(1 << 7)	/* non-fifo mode switch */
58#define FSCL	(1 << 6)	/* override SCL pin */
59#define FSDA	(1 << 5)	/* override SDA pin */
60#define OBPC	(1 << 4)	/* override pins */
61#define MIE	(1 << 3)	/* master if enable */
62#define TSBE	(1 << 2)
63#define FSB	(1 << 1)	/* force stop bit */
64#define ESG	(1 << 0)	/* en startbit gen */
65
66/* ICSSR (also for ICSIER) */
67#define GCAR	(1 << 6)	/* general call received */
68#define STM	(1 << 5)	/* slave transmit mode */
69#define SSR	(1 << 4)	/* stop received */
70#define SDE	(1 << 3)	/* slave data empty */
71#define SDT	(1 << 2)	/* slave data transmitted */
72#define SDR	(1 << 1)	/* slave data received */
73#define SAR	(1 << 0)	/* slave addr received */
74
75/* ICMSR (also for ICMIE) */
76#define MNR	(1 << 6)	/* nack received */
77#define MAL	(1 << 5)	/* arbitration lost */
78#define MST	(1 << 4)	/* sent a stop */
79#define MDE	(1 << 3)
80#define MDT	(1 << 2)
81#define MDR	(1 << 1)
82#define MAT	(1 << 0)	/* slave addr xfer done */
83
84
85#define RCAR_BUS_PHASE_START	(MDBS | MIE | ESG)
86#define RCAR_BUS_PHASE_DATA	(MDBS | MIE)
87#define RCAR_BUS_PHASE_STOP	(MDBS | MIE | FSB)
88
89#define RCAR_IRQ_SEND	(MNR | MAL | MST | MAT | MDE)
90#define RCAR_IRQ_RECV	(MNR | MAL | MST | MAT | MDR)
91#define RCAR_IRQ_STOP	(MST)
92
93#define RCAR_IRQ_ACK_SEND	(~(MAT | MDE) & 0xFF)
94#define RCAR_IRQ_ACK_RECV	(~(MAT | MDR) & 0xFF)
95
96#define ID_LAST_MSG	(1 << 0)
97#define ID_IOERROR	(1 << 1)
98#define ID_DONE		(1 << 2)
99#define ID_ARBLOST	(1 << 3)
100#define ID_NACK		(1 << 4)
101
102enum rcar_i2c_type {
103	I2C_RCAR_GEN1,
104	I2C_RCAR_GEN2,
105	I2C_RCAR_GEN3,
106};
107
108struct rcar_i2c_priv {
109	void __iomem *io;
110	struct i2c_adapter adap;
111	struct i2c_msg	*msg;
112	struct clk *clk;
113
114	spinlock_t lock;
115	wait_queue_head_t wait;
116
117	int pos;
118	u32 icccr;
119	u32 flags;
120	enum rcar_i2c_type devtype;
121	struct i2c_client *slave;
122};
123
124#define rcar_i2c_priv_to_dev(p)		((p)->adap.dev.parent)
125#define rcar_i2c_is_recv(p)		((p)->msg->flags & I2C_M_RD)
126
127#define rcar_i2c_flags_set(p, f)	((p)->flags |= (f))
128#define rcar_i2c_flags_has(p, f)	((p)->flags & (f))
129
130#define LOOP_TIMEOUT	1024
131
132
133static void rcar_i2c_write(struct rcar_i2c_priv *priv, int reg, u32 val)
134{
135	writel(val, priv->io + reg);
136}
137
138static u32 rcar_i2c_read(struct rcar_i2c_priv *priv, int reg)
139{
140	return readl(priv->io + reg);
141}
142
143static void rcar_i2c_init(struct rcar_i2c_priv *priv)
144{
145	/* reset master mode */
146	rcar_i2c_write(priv, ICMIER, 0);
147	rcar_i2c_write(priv, ICMCR, 0);
148	rcar_i2c_write(priv, ICMSR, 0);
149	rcar_i2c_write(priv, ICMAR, 0);
150}
151
152static int rcar_i2c_bus_barrier(struct rcar_i2c_priv *priv)
153{
154	int i;
155
156	for (i = 0; i < LOOP_TIMEOUT; i++) {
157		/* make sure that bus is not busy */
158		if (!(rcar_i2c_read(priv, ICMCR) & FSDA))
159			return 0;
160		udelay(1);
161	}
162
163	return -EBUSY;
164}
165
166static int rcar_i2c_clock_calculate(struct rcar_i2c_priv *priv,
167				    u32 bus_speed,
168				    struct device *dev)
169{
170	u32 scgd, cdf;
171	u32 round, ick;
172	u32 scl;
173	u32 cdf_width;
174	unsigned long rate;
175
176	switch (priv->devtype) {
177	case I2C_RCAR_GEN1:
178		cdf_width = 2;
179		break;
180	case I2C_RCAR_GEN2:
181	case I2C_RCAR_GEN3:
182		cdf_width = 3;
183		break;
184	default:
185		dev_err(dev, "device type error\n");
186		return -EIO;
187	}
188
189	/*
190	 * calculate SCL clock
191	 * see
192	 *	ICCCR
193	 *
194	 * ick	= clkp / (1 + CDF)
195	 * SCL	= ick / (20 + SCGD * 8 + F[(ticf + tr + intd) * ick])
196	 *
197	 * ick  : I2C internal clock < 20 MHz
198	 * ticf : I2C SCL falling time  =  35 ns here
199	 * tr   : I2C SCL rising  time  = 200 ns here
200	 * intd : LSI internal delay    =  50 ns here
201	 * clkp : peripheral_clk
202	 * F[]  : integer up-valuation
203	 */
204	rate = clk_get_rate(priv->clk);
205	cdf = rate / 20000000;
206	if (cdf >= 1U << cdf_width) {
207		dev_err(dev, "Input clock %lu too high\n", rate);
208		return -EIO;
209	}
210	ick = rate / (cdf + 1);
211
212	/*
213	 * it is impossible to calculate large scale
214	 * number on u32. separate it
215	 *
216	 * F[(ticf + tr + intd) * ick]
217	 *  = F[(35 + 200 + 50)ns * ick]
218	 *  = F[285 * ick / 1000000000]
219	 *  = F[(ick / 1000000) * 285 / 1000]
220	 */
221	round = (ick + 500000) / 1000000 * 285;
222	round = (round + 500) / 1000;
223
224	/*
225	 * SCL	= ick / (20 + SCGD * 8 + F[(ticf + tr + intd) * ick])
226	 *
227	 * Calculation result (= SCL) should be less than
228	 * bus_speed for hardware safety
229	 *
230	 * We could use something along the lines of
231	 *	div = ick / (bus_speed + 1) + 1;
232	 *	scgd = (div - 20 - round + 7) / 8;
233	 *	scl = ick / (20 + (scgd * 8) + round);
234	 * (not fully verified) but that would get pretty involved
235	 */
236	for (scgd = 0; scgd < 0x40; scgd++) {
237		scl = ick / (20 + (scgd * 8) + round);
238		if (scl <= bus_speed)
239			goto scgd_find;
240	}
241	dev_err(dev, "it is impossible to calculate best SCL\n");
242	return -EIO;
243
244scgd_find:
245	dev_dbg(dev, "clk %d/%d(%lu), round %u, CDF:0x%x, SCGD: 0x%x\n",
246		scl, bus_speed, clk_get_rate(priv->clk), round, cdf, scgd);
247
248	/*
249	 * keep icccr value
250	 */
251	priv->icccr = scgd << cdf_width | cdf;
252
253	return 0;
254}
255
256static void rcar_i2c_prepare_msg(struct rcar_i2c_priv *priv)
257{
258	int read = !!rcar_i2c_is_recv(priv);
259
260	rcar_i2c_write(priv, ICMAR, (priv->msg->addr << 1) | read);
261	rcar_i2c_write(priv, ICMSR, 0);
262	rcar_i2c_write(priv, ICMCR, RCAR_BUS_PHASE_START);
263	rcar_i2c_write(priv, ICMIER, read ? RCAR_IRQ_RECV : RCAR_IRQ_SEND);
264}
265
266/*
267 *		interrupt functions
268 */
269static int rcar_i2c_irq_send(struct rcar_i2c_priv *priv, u32 msr)
270{
271	struct i2c_msg *msg = priv->msg;
272
273	/*
274	 * FIXME
275	 * sometimes, unknown interrupt happened.
276	 * Do nothing
277	 */
278	if (!(msr & MDE))
279		return 0;
280
281	/*
282	 * If address transfer phase finished,
283	 * goto data phase.
284	 */
285	if (msr & MAT)
286		rcar_i2c_write(priv, ICMCR, RCAR_BUS_PHASE_DATA);
287
288	if (priv->pos < msg->len) {
289		/*
290		 * Prepare next data to ICRXTX register.
291		 * This data will go to _SHIFT_ register.
292		 *
293		 *    *
294		 * [ICRXTX] -> [SHIFT] -> [I2C bus]
295		 */
296		rcar_i2c_write(priv, ICRXTX, msg->buf[priv->pos]);
297		priv->pos++;
298
299	} else {
300		/*
301		 * The last data was pushed to ICRXTX on _PREV_ empty irq.
302		 * It is on _SHIFT_ register, and will sent to I2C bus.
303		 *
304		 *		  *
305		 * [ICRXTX] -> [SHIFT] -> [I2C bus]
306		 */
307
308		if (priv->flags & ID_LAST_MSG)
309			/*
310			 * If current msg is the _LAST_ msg,
311			 * prepare stop condition here.
312			 * ID_DONE will be set on STOP irq.
313			 */
314			rcar_i2c_write(priv, ICMCR, RCAR_BUS_PHASE_STOP);
315		else
316			/*
317			 * If current msg is _NOT_ last msg,
318			 * it doesn't call stop phase.
319			 * thus, there is no STOP irq.
320			 * return ID_DONE here.
321			 */
322			return ID_DONE;
323	}
324
325	rcar_i2c_write(priv, ICMSR, RCAR_IRQ_ACK_SEND);
326
327	return 0;
328}
329
330static int rcar_i2c_irq_recv(struct rcar_i2c_priv *priv, u32 msr)
331{
332	struct i2c_msg *msg = priv->msg;
333
334	/*
335	 * FIXME
336	 * sometimes, unknown interrupt happened.
337	 * Do nothing
338	 */
339	if (!(msr & MDR))
340		return 0;
341
342	if (msr & MAT) {
343		/*
344		 * Address transfer phase finished,
345		 * but, there is no data at this point.
346		 * Do nothing.
347		 */
348	} else if (priv->pos < msg->len) {
349		/*
350		 * get received data
351		 */
352		msg->buf[priv->pos] = rcar_i2c_read(priv, ICRXTX);
353		priv->pos++;
354	}
355
356	/*
357	 * If next received data is the _LAST_,
358	 * go to STOP phase,
359	 * otherwise, go to DATA phase.
360	 */
361	if (priv->pos + 1 >= msg->len)
362		rcar_i2c_write(priv, ICMCR, RCAR_BUS_PHASE_STOP);
363	else
364		rcar_i2c_write(priv, ICMCR, RCAR_BUS_PHASE_DATA);
365
366	rcar_i2c_write(priv, ICMSR, RCAR_IRQ_ACK_RECV);
367
368	return 0;
369}
370
371static bool rcar_i2c_slave_irq(struct rcar_i2c_priv *priv)
372{
373	u32 ssr_raw, ssr_filtered;
374	u8 value;
375
376	ssr_raw = rcar_i2c_read(priv, ICSSR) & 0xff;
377	ssr_filtered = ssr_raw & rcar_i2c_read(priv, ICSIER);
378
379	if (!ssr_filtered)
380		return false;
381
382	/* address detected */
383	if (ssr_filtered & SAR) {
384		/* read or write request */
385		if (ssr_raw & STM) {
386			i2c_slave_event(priv->slave, I2C_SLAVE_READ_REQUESTED, &value);
387			rcar_i2c_write(priv, ICRXTX, value);
388			rcar_i2c_write(priv, ICSIER, SDE | SSR | SAR);
389		} else {
390			i2c_slave_event(priv->slave, I2C_SLAVE_WRITE_REQUESTED, &value);
391			rcar_i2c_read(priv, ICRXTX);	/* dummy read */
392			rcar_i2c_write(priv, ICSIER, SDR | SSR | SAR);
393		}
394
395		rcar_i2c_write(priv, ICSSR, ~SAR & 0xff);
396	}
397
398	/* master sent stop */
399	if (ssr_filtered & SSR) {
400		i2c_slave_event(priv->slave, I2C_SLAVE_STOP, &value);
401		rcar_i2c_write(priv, ICSIER, SAR | SSR);
402		rcar_i2c_write(priv, ICSSR, ~SSR & 0xff);
403	}
404
405	/* master wants to write to us */
406	if (ssr_filtered & SDR) {
407		int ret;
408
409		value = rcar_i2c_read(priv, ICRXTX);
410		ret = i2c_slave_event(priv->slave, I2C_SLAVE_WRITE_RECEIVED, &value);
411		/* Send NACK in case of error */
412		rcar_i2c_write(priv, ICSCR, SIE | SDBS | (ret < 0 ? FNA : 0));
413		rcar_i2c_write(priv, ICSSR, ~SDR & 0xff);
414	}
415
416	/* master wants to read from us */
417	if (ssr_filtered & SDE) {
418		i2c_slave_event(priv->slave, I2C_SLAVE_READ_PROCESSED, &value);
419		rcar_i2c_write(priv, ICRXTX, value);
420		rcar_i2c_write(priv, ICSSR, ~SDE & 0xff);
421	}
422
423	return true;
424}
425
426static irqreturn_t rcar_i2c_irq(int irq, void *ptr)
427{
428	struct rcar_i2c_priv *priv = ptr;
429	irqreturn_t result = IRQ_HANDLED;
430	u32 msr;
431
432	/*-------------- spin lock -----------------*/
433	spin_lock(&priv->lock);
434
435	if (rcar_i2c_slave_irq(priv))
436		goto exit;
437
438	msr = rcar_i2c_read(priv, ICMSR);
439
440	/* Only handle interrupts that are currently enabled */
441	msr &= rcar_i2c_read(priv, ICMIER);
442	if (!msr) {
443		result = IRQ_NONE;
444		goto exit;
445	}
446
447	/* Arbitration lost */
448	if (msr & MAL) {
449		rcar_i2c_flags_set(priv, (ID_DONE | ID_ARBLOST));
450		goto out;
451	}
452
453	/* Nack */
454	if (msr & MNR) {
455		/* go to stop phase */
456		rcar_i2c_write(priv, ICMCR, RCAR_BUS_PHASE_STOP);
457		rcar_i2c_write(priv, ICMIER, RCAR_IRQ_STOP);
458		rcar_i2c_flags_set(priv, ID_NACK);
459		goto out;
460	}
461
462	/* Stop */
463	if (msr & MST) {
464		rcar_i2c_flags_set(priv, ID_DONE);
465		goto out;
466	}
467
468	if (rcar_i2c_is_recv(priv))
469		rcar_i2c_flags_set(priv, rcar_i2c_irq_recv(priv, msr));
470	else
471		rcar_i2c_flags_set(priv, rcar_i2c_irq_send(priv, msr));
472
473out:
474	if (rcar_i2c_flags_has(priv, ID_DONE)) {
475		rcar_i2c_write(priv, ICMIER, 0);
476		rcar_i2c_write(priv, ICMSR, 0);
477		wake_up(&priv->wait);
478	}
479
480exit:
481	spin_unlock(&priv->lock);
482	/*-------------- spin unlock -----------------*/
483
484	return result;
485}
486
487static int rcar_i2c_master_xfer(struct i2c_adapter *adap,
488				struct i2c_msg *msgs,
489				int num)
490{
491	struct rcar_i2c_priv *priv = i2c_get_adapdata(adap);
492	struct device *dev = rcar_i2c_priv_to_dev(priv);
493	unsigned long flags;
494	int i, ret;
495	long timeout;
496
497	pm_runtime_get_sync(dev);
498
499	/*-------------- spin lock -----------------*/
500	spin_lock_irqsave(&priv->lock, flags);
501
502	rcar_i2c_init(priv);
503	/* start clock */
504	rcar_i2c_write(priv, ICCCR, priv->icccr);
505
506	spin_unlock_irqrestore(&priv->lock, flags);
507	/*-------------- spin unlock -----------------*/
508
509	ret = rcar_i2c_bus_barrier(priv);
510	if (ret < 0)
511		goto out;
512
513	for (i = 0; i < num; i++) {
514		/* This HW can't send STOP after address phase */
515		if (msgs[i].len == 0) {
516			ret = -EOPNOTSUPP;
517			break;
518		}
519
520		/*-------------- spin lock -----------------*/
521		spin_lock_irqsave(&priv->lock, flags);
522
523		/* init each data */
524		priv->msg	= &msgs[i];
525		priv->pos	= 0;
526		priv->flags	= 0;
527		if (i == num - 1)
528			rcar_i2c_flags_set(priv, ID_LAST_MSG);
529
530		rcar_i2c_prepare_msg(priv);
531
532		spin_unlock_irqrestore(&priv->lock, flags);
533		/*-------------- spin unlock -----------------*/
534
535		timeout = wait_event_timeout(priv->wait,
536					     rcar_i2c_flags_has(priv, ID_DONE),
537					     adap->timeout);
538		if (!timeout) {
539			ret = -ETIMEDOUT;
540			break;
541		}
542
543		if (rcar_i2c_flags_has(priv, ID_NACK)) {
544			ret = -ENXIO;
545			break;
546		}
547
548		if (rcar_i2c_flags_has(priv, ID_ARBLOST)) {
549			ret = -EAGAIN;
550			break;
551		}
552
553		if (rcar_i2c_flags_has(priv, ID_IOERROR)) {
554			ret = -EIO;
555			break;
556		}
557
558		ret = i + 1; /* The number of transfer */
559	}
560out:
561	pm_runtime_put(dev);
562
563	if (ret < 0 && ret != -ENXIO)
564		dev_err(dev, "error %d : %x\n", ret, priv->flags);
565
566	return ret;
567}
568
569static int rcar_reg_slave(struct i2c_client *slave)
570{
571	struct rcar_i2c_priv *priv = i2c_get_adapdata(slave->adapter);
572
573	if (priv->slave)
574		return -EBUSY;
575
576	if (slave->flags & I2C_CLIENT_TEN)
577		return -EAFNOSUPPORT;
578
579	pm_runtime_get_sync(rcar_i2c_priv_to_dev(priv));
580
581	priv->slave = slave;
582	rcar_i2c_write(priv, ICSAR, slave->addr);
583	rcar_i2c_write(priv, ICSSR, 0);
584	rcar_i2c_write(priv, ICSIER, SAR | SSR);
585	rcar_i2c_write(priv, ICSCR, SIE | SDBS);
586
587	return 0;
588}
589
590static int rcar_unreg_slave(struct i2c_client *slave)
591{
592	struct rcar_i2c_priv *priv = i2c_get_adapdata(slave->adapter);
593
594	WARN_ON(!priv->slave);
595
596	rcar_i2c_write(priv, ICSIER, 0);
597	rcar_i2c_write(priv, ICSCR, 0);
598
599	priv->slave = NULL;
600
601	pm_runtime_put(rcar_i2c_priv_to_dev(priv));
602
603	return 0;
604}
605
606static u32 rcar_i2c_func(struct i2c_adapter *adap)
607{
608	/* This HW can't do SMBUS_QUICK and NOSTART */
609	return I2C_FUNC_I2C | I2C_FUNC_SLAVE |
610		(I2C_FUNC_SMBUS_EMUL & ~I2C_FUNC_SMBUS_QUICK);
611}
612
613static const struct i2c_algorithm rcar_i2c_algo = {
614	.master_xfer	= rcar_i2c_master_xfer,
615	.functionality	= rcar_i2c_func,
616	.reg_slave	= rcar_reg_slave,
617	.unreg_slave	= rcar_unreg_slave,
618};
619
620static const struct of_device_id rcar_i2c_dt_ids[] = {
621	{ .compatible = "renesas,i2c-rcar", .data = (void *)I2C_RCAR_GEN1 },
622	{ .compatible = "renesas,i2c-r8a7778", .data = (void *)I2C_RCAR_GEN1 },
623	{ .compatible = "renesas,i2c-r8a7779", .data = (void *)I2C_RCAR_GEN1 },
624	{ .compatible = "renesas,i2c-r8a7790", .data = (void *)I2C_RCAR_GEN2 },
625	{ .compatible = "renesas,i2c-r8a7791", .data = (void *)I2C_RCAR_GEN2 },
626	{ .compatible = "renesas,i2c-r8a7792", .data = (void *)I2C_RCAR_GEN2 },
627	{ .compatible = "renesas,i2c-r8a7793", .data = (void *)I2C_RCAR_GEN2 },
628	{ .compatible = "renesas,i2c-r8a7794", .data = (void *)I2C_RCAR_GEN2 },
629	{ .compatible = "renesas,i2c-r8a7795", .data = (void *)I2C_RCAR_GEN3 },
630	{},
631};
632MODULE_DEVICE_TABLE(of, rcar_i2c_dt_ids);
633
634static int rcar_i2c_probe(struct platform_device *pdev)
635{
636	struct rcar_i2c_priv *priv;
637	struct i2c_adapter *adap;
638	struct resource *res;
639	struct device *dev = &pdev->dev;
640	u32 bus_speed;
641	int irq, ret;
642
643	priv = devm_kzalloc(dev, sizeof(struct rcar_i2c_priv), GFP_KERNEL);
644	if (!priv)
645		return -ENOMEM;
646
647	priv->clk = devm_clk_get(dev, NULL);
648	if (IS_ERR(priv->clk)) {
649		dev_err(dev, "cannot get clock\n");
650		return PTR_ERR(priv->clk);
651	}
652
653	bus_speed = 100000; /* default 100 kHz */
654	of_property_read_u32(dev->of_node, "clock-frequency", &bus_speed);
655
656	priv->devtype = (enum rcar_i2c_type)of_match_device(rcar_i2c_dt_ids, dev)->data;
657
658	ret = rcar_i2c_clock_calculate(priv, bus_speed, dev);
659	if (ret < 0)
660		return ret;
661
662	res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
663	priv->io = devm_ioremap_resource(dev, res);
664	if (IS_ERR(priv->io))
665		return PTR_ERR(priv->io);
666
667	irq = platform_get_irq(pdev, 0);
668	init_waitqueue_head(&priv->wait);
669	spin_lock_init(&priv->lock);
670
671	adap = &priv->adap;
672	adap->nr = pdev->id;
673	adap->algo = &rcar_i2c_algo;
674	adap->class = I2C_CLASS_DEPRECATED;
675	adap->retries = 3;
676	adap->dev.parent = dev;
677	adap->dev.of_node = dev->of_node;
678	i2c_set_adapdata(adap, priv);
679	strlcpy(adap->name, pdev->name, sizeof(adap->name));
680
681	ret = devm_request_irq(dev, irq, rcar_i2c_irq, 0,
682			       dev_name(dev), priv);
683	if (ret < 0) {
684		dev_err(dev, "cannot get irq %d\n", irq);
685		return ret;
686	}
687
688	pm_runtime_enable(dev);
689	platform_set_drvdata(pdev, priv);
690
691	ret = i2c_add_numbered_adapter(adap);
692	if (ret < 0) {
693		dev_err(dev, "reg adap failed: %d\n", ret);
694		pm_runtime_disable(dev);
695		return ret;
696	}
697
698	dev_info(dev, "probed\n");
699
700	return 0;
701}
702
703static int rcar_i2c_remove(struct platform_device *pdev)
704{
705	struct rcar_i2c_priv *priv = platform_get_drvdata(pdev);
706	struct device *dev = &pdev->dev;
707
708	i2c_del_adapter(&priv->adap);
709	pm_runtime_disable(dev);
710
711	return 0;
712}
713
714static struct platform_driver rcar_i2c_driver = {
715	.driver	= {
716		.name	= "i2c-rcar",
717		.of_match_table = rcar_i2c_dt_ids,
718	},
719	.probe		= rcar_i2c_probe,
720	.remove		= rcar_i2c_remove,
721};
722
723module_platform_driver(rcar_i2c_driver);
724
725MODULE_LICENSE("GPL v2");
726MODULE_DESCRIPTION("Renesas R-Car I2C bus driver");
727MODULE_AUTHOR("Kuninori Morimoto <kuninori.morimoto.gx@renesas.com>");
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