xref: /linux/drivers/i2c/busses/i2c-pxa.c (revision 5cc619db5c34146ee821acd08382b9d78579b52e)
1 /*
2  *  i2c_adap_pxa.c
3  *
4  *  I2C adapter for the PXA I2C bus access.
5  *
6  *  Copyright (C) 2002 Intrinsyc Software Inc.
7  *  Copyright (C) 2004-2005 Deep Blue Solutions Ltd.
8  *
9  *  This program is free software; you can redistribute it and/or modify
10  *  it under the terms of the GNU General Public License version 2 as
11  *  published by the Free Software Foundation.
12  *
13  *  History:
14  *    Apr 2002: Initial version [CS]
15  *    Jun 2002: Properly separated algo/adap [FB]
16  *    Jan 2003: Fixed several bugs concerning interrupt handling [Kai-Uwe Bloem]
17  *    Jan 2003: added limited signal handling [Kai-Uwe Bloem]
18  *    Sep 2004: Major rework to ensure efficient bus handling [RMK]
19  *    Dec 2004: Added support for PXA27x and slave device probing [Liam Girdwood]
20  *    Feb 2005: Rework slave mode handling [RMK]
21  */
22 #include <linux/kernel.h>
23 #include <linux/module.h>
24 #include <linux/i2c.h>
25 #include <linux/init.h>
26 #include <linux/time.h>
27 #include <linux/sched.h>
28 #include <linux/delay.h>
29 #include <linux/errno.h>
30 #include <linux/interrupt.h>
31 #include <linux/i2c-pxa.h>
32 #include <linux/of.h>
33 #include <linux/of_device.h>
34 #include <linux/platform_device.h>
35 #include <linux/err.h>
36 #include <linux/clk.h>
37 #include <linux/slab.h>
38 #include <linux/io.h>
39 #include <linux/i2c/pxa-i2c.h>
40 
41 #include <asm/irq.h>
42 
43 struct pxa_reg_layout {
44 	u32 ibmr;
45 	u32 idbr;
46 	u32 icr;
47 	u32 isr;
48 	u32 isar;
49 	u32 ilcr;
50 	u32 iwcr;
51 	u32 fm;
52 	u32 hs;
53 };
54 
55 enum pxa_i2c_types {
56 	REGS_PXA2XX,
57 	REGS_PXA3XX,
58 	REGS_CE4100,
59 	REGS_PXA910,
60 	REGS_A3700,
61 };
62 
63 #define ICR_BUSMODE_FM	(1 << 16)	   /* shifted fast mode for armada-3700 */
64 #define ICR_BUSMODE_HS	(1 << 17)	   /* shifted high speed mode for armada-3700 */
65 
66 /*
67  * I2C registers definitions
68  */
69 static struct pxa_reg_layout pxa_reg_layout[] = {
70 	[REGS_PXA2XX] = {
71 		.ibmr =	0x00,
72 		.idbr =	0x08,
73 		.icr =	0x10,
74 		.isr =	0x18,
75 		.isar =	0x20,
76 	},
77 	[REGS_PXA3XX] = {
78 		.ibmr =	0x00,
79 		.idbr =	0x04,
80 		.icr =	0x08,
81 		.isr =	0x0c,
82 		.isar =	0x10,
83 	},
84 	[REGS_CE4100] = {
85 		.ibmr =	0x14,
86 		.idbr =	0x0c,
87 		.icr =	0x00,
88 		.isr =	0x04,
89 		/* no isar register */
90 	},
91 	[REGS_PXA910] = {
92 		.ibmr = 0x00,
93 		.idbr = 0x08,
94 		.icr =	0x10,
95 		.isr =	0x18,
96 		.isar = 0x20,
97 		.ilcr = 0x28,
98 		.iwcr = 0x30,
99 	},
100 	[REGS_A3700] = {
101 		.ibmr =	0x00,
102 		.idbr =	0x04,
103 		.icr =	0x08,
104 		.isr =	0x0c,
105 		.isar =	0x10,
106 		.fm = ICR_BUSMODE_FM,
107 		.hs = ICR_BUSMODE_HS,
108 	},
109 };
110 
111 static const struct platform_device_id i2c_pxa_id_table[] = {
112 	{ "pxa2xx-i2c",		REGS_PXA2XX },
113 	{ "pxa3xx-pwri2c",	REGS_PXA3XX },
114 	{ "ce4100-i2c",		REGS_CE4100 },
115 	{ "pxa910-i2c",		REGS_PXA910 },
116 	{ "armada-3700-i2c",	REGS_A3700  },
117 	{ },
118 };
119 MODULE_DEVICE_TABLE(platform, i2c_pxa_id_table);
120 
121 /*
122  * I2C bit definitions
123  */
124 
125 #define ICR_START	(1 << 0)	   /* start bit */
126 #define ICR_STOP	(1 << 1)	   /* stop bit */
127 #define ICR_ACKNAK	(1 << 2)	   /* send ACK(0) or NAK(1) */
128 #define ICR_TB		(1 << 3)	   /* transfer byte bit */
129 #define ICR_MA		(1 << 4)	   /* master abort */
130 #define ICR_SCLE	(1 << 5)	   /* master clock enable */
131 #define ICR_IUE		(1 << 6)	   /* unit enable */
132 #define ICR_GCD		(1 << 7)	   /* general call disable */
133 #define ICR_ITEIE	(1 << 8)	   /* enable tx interrupts */
134 #define ICR_IRFIE	(1 << 9)	   /* enable rx interrupts */
135 #define ICR_BEIE	(1 << 10)	   /* enable bus error ints */
136 #define ICR_SSDIE	(1 << 11)	   /* slave STOP detected int enable */
137 #define ICR_ALDIE	(1 << 12)	   /* enable arbitration interrupt */
138 #define ICR_SADIE	(1 << 13)	   /* slave address detected int enable */
139 #define ICR_UR		(1 << 14)	   /* unit reset */
140 #define ICR_FM		(1 << 15)	   /* fast mode */
141 #define ICR_HS		(1 << 16)	   /* High Speed mode */
142 #define ICR_GPIOEN	(1 << 19)	   /* enable GPIO mode for SCL in HS */
143 
144 #define ISR_RWM		(1 << 0)	   /* read/write mode */
145 #define ISR_ACKNAK	(1 << 1)	   /* ack/nak status */
146 #define ISR_UB		(1 << 2)	   /* unit busy */
147 #define ISR_IBB		(1 << 3)	   /* bus busy */
148 #define ISR_SSD		(1 << 4)	   /* slave stop detected */
149 #define ISR_ALD		(1 << 5)	   /* arbitration loss detected */
150 #define ISR_ITE		(1 << 6)	   /* tx buffer empty */
151 #define ISR_IRF		(1 << 7)	   /* rx buffer full */
152 #define ISR_GCAD	(1 << 8)	   /* general call address detected */
153 #define ISR_SAD		(1 << 9)	   /* slave address detected */
154 #define ISR_BED		(1 << 10)	   /* bus error no ACK/NAK */
155 
156 /* bit field shift & mask */
157 #define ILCR_SLV_SHIFT		0
158 #define ILCR_SLV_MASK		(0x1FF << ILCR_SLV_SHIFT)
159 #define ILCR_FLV_SHIFT		9
160 #define ILCR_FLV_MASK		(0x1FF << ILCR_FLV_SHIFT)
161 #define ILCR_HLVL_SHIFT		18
162 #define ILCR_HLVL_MASK		(0x1FF << ILCR_HLVL_SHIFT)
163 #define ILCR_HLVH_SHIFT		27
164 #define ILCR_HLVH_MASK		(0x1F << ILCR_HLVH_SHIFT)
165 
166 #define IWCR_CNT_SHIFT		0
167 #define IWCR_CNT_MASK		(0x1F << IWCR_CNT_SHIFT)
168 #define IWCR_HS_CNT1_SHIFT	5
169 #define IWCR_HS_CNT1_MASK	(0x1F << IWCR_HS_CNT1_SHIFT)
170 #define IWCR_HS_CNT2_SHIFT	10
171 #define IWCR_HS_CNT2_MASK	(0x1F << IWCR_HS_CNT2_SHIFT)
172 
173 struct pxa_i2c {
174 	spinlock_t		lock;
175 	wait_queue_head_t	wait;
176 	struct i2c_msg		*msg;
177 	unsigned int		msg_num;
178 	unsigned int		msg_idx;
179 	unsigned int		msg_ptr;
180 	unsigned int		slave_addr;
181 	unsigned int		req_slave_addr;
182 
183 	struct i2c_adapter	adap;
184 	struct clk		*clk;
185 #ifdef CONFIG_I2C_PXA_SLAVE
186 	struct i2c_slave_client *slave;
187 #endif
188 
189 	unsigned int		irqlogidx;
190 	u32			isrlog[32];
191 	u32			icrlog[32];
192 
193 	void __iomem		*reg_base;
194 	void __iomem		*reg_ibmr;
195 	void __iomem		*reg_idbr;
196 	void __iomem		*reg_icr;
197 	void __iomem		*reg_isr;
198 	void __iomem		*reg_isar;
199 	void __iomem		*reg_ilcr;
200 	void __iomem		*reg_iwcr;
201 
202 	unsigned long		iobase;
203 	unsigned long		iosize;
204 
205 	int			irq;
206 	unsigned int		use_pio :1;
207 	unsigned int		fast_mode :1;
208 	unsigned int		high_mode:1;
209 	unsigned char		master_code;
210 	unsigned long		rate;
211 	bool			highmode_enter;
212 	u32			fm_mask;
213 	u32			hs_mask;
214 };
215 
216 #define _IBMR(i2c)	((i2c)->reg_ibmr)
217 #define _IDBR(i2c)	((i2c)->reg_idbr)
218 #define _ICR(i2c)	((i2c)->reg_icr)
219 #define _ISR(i2c)	((i2c)->reg_isr)
220 #define _ISAR(i2c)	((i2c)->reg_isar)
221 #define _ILCR(i2c)	((i2c)->reg_ilcr)
222 #define _IWCR(i2c)	((i2c)->reg_iwcr)
223 
224 /*
225  * I2C Slave mode address
226  */
227 #define I2C_PXA_SLAVE_ADDR      0x1
228 
229 #ifdef DEBUG
230 
231 struct bits {
232 	u32	mask;
233 	const char *set;
234 	const char *unset;
235 };
236 #define PXA_BIT(m, s, u)	{ .mask = m, .set = s, .unset = u }
237 
238 static inline void
239 decode_bits(const char *prefix, const struct bits *bits, int num, u32 val)
240 {
241 	printk("%s %08x: ", prefix, val);
242 	while (num--) {
243 		const char *str = val & bits->mask ? bits->set : bits->unset;
244 		if (str)
245 			printk("%s ", str);
246 		bits++;
247 	}
248 }
249 
250 static const struct bits isr_bits[] = {
251 	PXA_BIT(ISR_RWM,	"RX",		"TX"),
252 	PXA_BIT(ISR_ACKNAK,	"NAK",		"ACK"),
253 	PXA_BIT(ISR_UB,		"Bsy",		"Rdy"),
254 	PXA_BIT(ISR_IBB,	"BusBsy",	"BusRdy"),
255 	PXA_BIT(ISR_SSD,	"SlaveStop",	NULL),
256 	PXA_BIT(ISR_ALD,	"ALD",		NULL),
257 	PXA_BIT(ISR_ITE,	"TxEmpty",	NULL),
258 	PXA_BIT(ISR_IRF,	"RxFull",	NULL),
259 	PXA_BIT(ISR_GCAD,	"GenCall",	NULL),
260 	PXA_BIT(ISR_SAD,	"SlaveAddr",	NULL),
261 	PXA_BIT(ISR_BED,	"BusErr",	NULL),
262 };
263 
264 static void decode_ISR(unsigned int val)
265 {
266 	decode_bits(KERN_DEBUG "ISR", isr_bits, ARRAY_SIZE(isr_bits), val);
267 	printk("\n");
268 }
269 
270 static const struct bits icr_bits[] = {
271 	PXA_BIT(ICR_START,  "START",	NULL),
272 	PXA_BIT(ICR_STOP,   "STOP",	NULL),
273 	PXA_BIT(ICR_ACKNAK, "ACKNAK",	NULL),
274 	PXA_BIT(ICR_TB,     "TB",	NULL),
275 	PXA_BIT(ICR_MA,     "MA",	NULL),
276 	PXA_BIT(ICR_SCLE,   "SCLE",	"scle"),
277 	PXA_BIT(ICR_IUE,    "IUE",	"iue"),
278 	PXA_BIT(ICR_GCD,    "GCD",	NULL),
279 	PXA_BIT(ICR_ITEIE,  "ITEIE",	NULL),
280 	PXA_BIT(ICR_IRFIE,  "IRFIE",	NULL),
281 	PXA_BIT(ICR_BEIE,   "BEIE",	NULL),
282 	PXA_BIT(ICR_SSDIE,  "SSDIE",	NULL),
283 	PXA_BIT(ICR_ALDIE,  "ALDIE",	NULL),
284 	PXA_BIT(ICR_SADIE,  "SADIE",	NULL),
285 	PXA_BIT(ICR_UR,     "UR",		"ur"),
286 };
287 
288 #ifdef CONFIG_I2C_PXA_SLAVE
289 static void decode_ICR(unsigned int val)
290 {
291 	decode_bits(KERN_DEBUG "ICR", icr_bits, ARRAY_SIZE(icr_bits), val);
292 	printk("\n");
293 }
294 #endif
295 
296 static unsigned int i2c_debug = DEBUG;
297 
298 static void i2c_pxa_show_state(struct pxa_i2c *i2c, int lno, const char *fname)
299 {
300 	dev_dbg(&i2c->adap.dev, "state:%s:%d: ISR=%08x, ICR=%08x, IBMR=%02x\n", fname, lno,
301 		readl(_ISR(i2c)), readl(_ICR(i2c)), readl(_IBMR(i2c)));
302 }
303 
304 #define show_state(i2c) i2c_pxa_show_state(i2c, __LINE__, __func__)
305 
306 static void i2c_pxa_scream_blue_murder(struct pxa_i2c *i2c, const char *why)
307 {
308 	unsigned int i;
309 	struct device *dev = &i2c->adap.dev;
310 
311 	dev_err(dev, "slave_0x%x error: %s\n",
312 		i2c->req_slave_addr >> 1, why);
313 	dev_err(dev, "msg_num: %d msg_idx: %d msg_ptr: %d\n",
314 		i2c->msg_num, i2c->msg_idx, i2c->msg_ptr);
315 	dev_err(dev, "IBMR: %08x IDBR: %08x ICR: %08x ISR: %08x\n",
316 		readl(_IBMR(i2c)), readl(_IDBR(i2c)), readl(_ICR(i2c)),
317 		readl(_ISR(i2c)));
318 	dev_dbg(dev, "log: ");
319 	for (i = 0; i < i2c->irqlogidx; i++)
320 		pr_debug("[%08x:%08x] ", i2c->isrlog[i], i2c->icrlog[i]);
321 
322 	pr_debug("\n");
323 }
324 
325 #else /* ifdef DEBUG */
326 
327 #define i2c_debug	0
328 
329 #define show_state(i2c) do { } while (0)
330 #define decode_ISR(val) do { } while (0)
331 #define decode_ICR(val) do { } while (0)
332 #define i2c_pxa_scream_blue_murder(i2c, why) do { } while (0)
333 
334 #endif /* ifdef DEBUG / else */
335 
336 static void i2c_pxa_master_complete(struct pxa_i2c *i2c, int ret);
337 static irqreturn_t i2c_pxa_handler(int this_irq, void *dev_id);
338 
339 static inline int i2c_pxa_is_slavemode(struct pxa_i2c *i2c)
340 {
341 	return !(readl(_ICR(i2c)) & ICR_SCLE);
342 }
343 
344 static void i2c_pxa_abort(struct pxa_i2c *i2c)
345 {
346 	int i = 250;
347 
348 	if (i2c_pxa_is_slavemode(i2c)) {
349 		dev_dbg(&i2c->adap.dev, "%s: called in slave mode\n", __func__);
350 		return;
351 	}
352 
353 	while ((i > 0) && (readl(_IBMR(i2c)) & 0x1) == 0) {
354 		unsigned long icr = readl(_ICR(i2c));
355 
356 		icr &= ~ICR_START;
357 		icr |= ICR_ACKNAK | ICR_STOP | ICR_TB;
358 
359 		writel(icr, _ICR(i2c));
360 
361 		show_state(i2c);
362 
363 		mdelay(1);
364 		i --;
365 	}
366 
367 	writel(readl(_ICR(i2c)) & ~(ICR_MA | ICR_START | ICR_STOP),
368 	       _ICR(i2c));
369 }
370 
371 static int i2c_pxa_wait_bus_not_busy(struct pxa_i2c *i2c)
372 {
373 	int timeout = DEF_TIMEOUT;
374 
375 	while (timeout-- && readl(_ISR(i2c)) & (ISR_IBB | ISR_UB)) {
376 		if ((readl(_ISR(i2c)) & ISR_SAD) != 0)
377 			timeout += 4;
378 
379 		msleep(2);
380 		show_state(i2c);
381 	}
382 
383 	if (timeout < 0)
384 		show_state(i2c);
385 
386 	return timeout < 0 ? I2C_RETRY : 0;
387 }
388 
389 static int i2c_pxa_wait_master(struct pxa_i2c *i2c)
390 {
391 	unsigned long timeout = jiffies + HZ*4;
392 
393 	while (time_before(jiffies, timeout)) {
394 		if (i2c_debug > 1)
395 			dev_dbg(&i2c->adap.dev, "%s: %ld: ISR=%08x, ICR=%08x, IBMR=%02x\n",
396 				__func__, (long)jiffies, readl(_ISR(i2c)), readl(_ICR(i2c)), readl(_IBMR(i2c)));
397 
398 		if (readl(_ISR(i2c)) & ISR_SAD) {
399 			if (i2c_debug > 0)
400 				dev_dbg(&i2c->adap.dev, "%s: Slave detected\n", __func__);
401 			goto out;
402 		}
403 
404 		/* wait for unit and bus being not busy, and we also do a
405 		 * quick check of the i2c lines themselves to ensure they've
406 		 * gone high...
407 		 */
408 		if ((readl(_ISR(i2c)) & (ISR_UB | ISR_IBB)) == 0 && readl(_IBMR(i2c)) == 3) {
409 			if (i2c_debug > 0)
410 				dev_dbg(&i2c->adap.dev, "%s: done\n", __func__);
411 			return 1;
412 		}
413 
414 		msleep(1);
415 	}
416 
417 	if (i2c_debug > 0)
418 		dev_dbg(&i2c->adap.dev, "%s: did not free\n", __func__);
419  out:
420 	return 0;
421 }
422 
423 static int i2c_pxa_set_master(struct pxa_i2c *i2c)
424 {
425 	if (i2c_debug)
426 		dev_dbg(&i2c->adap.dev, "setting to bus master\n");
427 
428 	if ((readl(_ISR(i2c)) & (ISR_UB | ISR_IBB)) != 0) {
429 		dev_dbg(&i2c->adap.dev, "%s: unit is busy\n", __func__);
430 		if (!i2c_pxa_wait_master(i2c)) {
431 			dev_dbg(&i2c->adap.dev, "%s: error: unit busy\n", __func__);
432 			return I2C_RETRY;
433 		}
434 	}
435 
436 	writel(readl(_ICR(i2c)) | ICR_SCLE, _ICR(i2c));
437 	return 0;
438 }
439 
440 #ifdef CONFIG_I2C_PXA_SLAVE
441 static int i2c_pxa_wait_slave(struct pxa_i2c *i2c)
442 {
443 	unsigned long timeout = jiffies + HZ*1;
444 
445 	/* wait for stop */
446 
447 	show_state(i2c);
448 
449 	while (time_before(jiffies, timeout)) {
450 		if (i2c_debug > 1)
451 			dev_dbg(&i2c->adap.dev, "%s: %ld: ISR=%08x, ICR=%08x, IBMR=%02x\n",
452 				__func__, (long)jiffies, readl(_ISR(i2c)), readl(_ICR(i2c)), readl(_IBMR(i2c)));
453 
454 		if ((readl(_ISR(i2c)) & (ISR_UB|ISR_IBB)) == 0 ||
455 		    (readl(_ISR(i2c)) & ISR_SAD) != 0 ||
456 		    (readl(_ICR(i2c)) & ICR_SCLE) == 0) {
457 			if (i2c_debug > 1)
458 				dev_dbg(&i2c->adap.dev, "%s: done\n", __func__);
459 			return 1;
460 		}
461 
462 		msleep(1);
463 	}
464 
465 	if (i2c_debug > 0)
466 		dev_dbg(&i2c->adap.dev, "%s: did not free\n", __func__);
467 	return 0;
468 }
469 
470 /*
471  * clear the hold on the bus, and take of anything else
472  * that has been configured
473  */
474 static void i2c_pxa_set_slave(struct pxa_i2c *i2c, int errcode)
475 {
476 	show_state(i2c);
477 
478 	if (errcode < 0) {
479 		udelay(100);   /* simple delay */
480 	} else {
481 		/* we need to wait for the stop condition to end */
482 
483 		/* if we where in stop, then clear... */
484 		if (readl(_ICR(i2c)) & ICR_STOP) {
485 			udelay(100);
486 			writel(readl(_ICR(i2c)) & ~ICR_STOP, _ICR(i2c));
487 		}
488 
489 		if (!i2c_pxa_wait_slave(i2c)) {
490 			dev_err(&i2c->adap.dev, "%s: wait timedout\n",
491 				__func__);
492 			return;
493 		}
494 	}
495 
496 	writel(readl(_ICR(i2c)) & ~(ICR_STOP|ICR_ACKNAK|ICR_MA), _ICR(i2c));
497 	writel(readl(_ICR(i2c)) & ~ICR_SCLE, _ICR(i2c));
498 
499 	if (i2c_debug) {
500 		dev_dbg(&i2c->adap.dev, "ICR now %08x, ISR %08x\n", readl(_ICR(i2c)), readl(_ISR(i2c)));
501 		decode_ICR(readl(_ICR(i2c)));
502 	}
503 }
504 #else
505 #define i2c_pxa_set_slave(i2c, err)	do { } while (0)
506 #endif
507 
508 static void i2c_pxa_reset(struct pxa_i2c *i2c)
509 {
510 	pr_debug("Resetting I2C Controller Unit\n");
511 
512 	/* abort any transfer currently under way */
513 	i2c_pxa_abort(i2c);
514 
515 	/* reset according to 9.8 */
516 	writel(ICR_UR, _ICR(i2c));
517 	writel(I2C_ISR_INIT, _ISR(i2c));
518 	writel(readl(_ICR(i2c)) & ~ICR_UR, _ICR(i2c));
519 
520 	if (i2c->reg_isar && IS_ENABLED(CONFIG_I2C_PXA_SLAVE))
521 		writel(i2c->slave_addr, _ISAR(i2c));
522 
523 	/* set control register values */
524 	writel(I2C_ICR_INIT | (i2c->fast_mode ? i2c->fm_mask : 0), _ICR(i2c));
525 	writel(readl(_ICR(i2c)) | (i2c->high_mode ? i2c->hs_mask : 0), _ICR(i2c));
526 
527 #ifdef CONFIG_I2C_PXA_SLAVE
528 	dev_info(&i2c->adap.dev, "Enabling slave mode\n");
529 	writel(readl(_ICR(i2c)) | ICR_SADIE | ICR_ALDIE | ICR_SSDIE, _ICR(i2c));
530 #endif
531 
532 	i2c_pxa_set_slave(i2c, 0);
533 
534 	/* enable unit */
535 	writel(readl(_ICR(i2c)) | ICR_IUE, _ICR(i2c));
536 	udelay(100);
537 }
538 
539 
540 #ifdef CONFIG_I2C_PXA_SLAVE
541 /*
542  * PXA I2C Slave mode
543  */
544 
545 static void i2c_pxa_slave_txempty(struct pxa_i2c *i2c, u32 isr)
546 {
547 	if (isr & ISR_BED) {
548 		/* what should we do here? */
549 	} else {
550 		int ret = 0;
551 
552 		if (i2c->slave != NULL)
553 			ret = i2c->slave->read(i2c->slave->data);
554 
555 		writel(ret, _IDBR(i2c));
556 		writel(readl(_ICR(i2c)) | ICR_TB, _ICR(i2c));   /* allow next byte */
557 	}
558 }
559 
560 static void i2c_pxa_slave_rxfull(struct pxa_i2c *i2c, u32 isr)
561 {
562 	unsigned int byte = readl(_IDBR(i2c));
563 
564 	if (i2c->slave != NULL)
565 		i2c->slave->write(i2c->slave->data, byte);
566 
567 	writel(readl(_ICR(i2c)) | ICR_TB, _ICR(i2c));
568 }
569 
570 static void i2c_pxa_slave_start(struct pxa_i2c *i2c, u32 isr)
571 {
572 	int timeout;
573 
574 	if (i2c_debug > 0)
575 		dev_dbg(&i2c->adap.dev, "SAD, mode is slave-%cx\n",
576 		       (isr & ISR_RWM) ? 'r' : 't');
577 
578 	if (i2c->slave != NULL)
579 		i2c->slave->event(i2c->slave->data,
580 				 (isr & ISR_RWM) ? I2C_SLAVE_EVENT_START_READ : I2C_SLAVE_EVENT_START_WRITE);
581 
582 	/*
583 	 * slave could interrupt in the middle of us generating a
584 	 * start condition... if this happens, we'd better back off
585 	 * and stop holding the poor thing up
586 	 */
587 	writel(readl(_ICR(i2c)) & ~(ICR_START|ICR_STOP), _ICR(i2c));
588 	writel(readl(_ICR(i2c)) | ICR_TB, _ICR(i2c));
589 
590 	timeout = 0x10000;
591 
592 	while (1) {
593 		if ((readl(_IBMR(i2c)) & 2) == 2)
594 			break;
595 
596 		timeout--;
597 
598 		if (timeout <= 0) {
599 			dev_err(&i2c->adap.dev, "timeout waiting for SCL high\n");
600 			break;
601 		}
602 	}
603 
604 	writel(readl(_ICR(i2c)) & ~ICR_SCLE, _ICR(i2c));
605 }
606 
607 static void i2c_pxa_slave_stop(struct pxa_i2c *i2c)
608 {
609 	if (i2c_debug > 2)
610 		dev_dbg(&i2c->adap.dev, "ISR: SSD (Slave Stop)\n");
611 
612 	if (i2c->slave != NULL)
613 		i2c->slave->event(i2c->slave->data, I2C_SLAVE_EVENT_STOP);
614 
615 	if (i2c_debug > 2)
616 		dev_dbg(&i2c->adap.dev, "ISR: SSD (Slave Stop) acked\n");
617 
618 	/*
619 	 * If we have a master-mode message waiting,
620 	 * kick it off now that the slave has completed.
621 	 */
622 	if (i2c->msg)
623 		i2c_pxa_master_complete(i2c, I2C_RETRY);
624 }
625 #else
626 static void i2c_pxa_slave_txempty(struct pxa_i2c *i2c, u32 isr)
627 {
628 	if (isr & ISR_BED) {
629 		/* what should we do here? */
630 	} else {
631 		writel(0, _IDBR(i2c));
632 		writel(readl(_ICR(i2c)) | ICR_TB, _ICR(i2c));
633 	}
634 }
635 
636 static void i2c_pxa_slave_rxfull(struct pxa_i2c *i2c, u32 isr)
637 {
638 	writel(readl(_ICR(i2c)) | ICR_TB | ICR_ACKNAK, _ICR(i2c));
639 }
640 
641 static void i2c_pxa_slave_start(struct pxa_i2c *i2c, u32 isr)
642 {
643 	int timeout;
644 
645 	/*
646 	 * slave could interrupt in the middle of us generating a
647 	 * start condition... if this happens, we'd better back off
648 	 * and stop holding the poor thing up
649 	 */
650 	writel(readl(_ICR(i2c)) & ~(ICR_START|ICR_STOP), _ICR(i2c));
651 	writel(readl(_ICR(i2c)) | ICR_TB | ICR_ACKNAK, _ICR(i2c));
652 
653 	timeout = 0x10000;
654 
655 	while (1) {
656 		if ((readl(_IBMR(i2c)) & 2) == 2)
657 			break;
658 
659 		timeout--;
660 
661 		if (timeout <= 0) {
662 			dev_err(&i2c->adap.dev, "timeout waiting for SCL high\n");
663 			break;
664 		}
665 	}
666 
667 	writel(readl(_ICR(i2c)) & ~ICR_SCLE, _ICR(i2c));
668 }
669 
670 static void i2c_pxa_slave_stop(struct pxa_i2c *i2c)
671 {
672 	if (i2c->msg)
673 		i2c_pxa_master_complete(i2c, I2C_RETRY);
674 }
675 #endif
676 
677 /*
678  * PXA I2C Master mode
679  */
680 
681 static inline unsigned int i2c_pxa_addr_byte(struct i2c_msg *msg)
682 {
683 	unsigned int addr = (msg->addr & 0x7f) << 1;
684 
685 	if (msg->flags & I2C_M_RD)
686 		addr |= 1;
687 
688 	return addr;
689 }
690 
691 static inline void i2c_pxa_start_message(struct pxa_i2c *i2c)
692 {
693 	u32 icr;
694 
695 	/*
696 	 * Step 1: target slave address into IDBR
697 	 */
698 	writel(i2c_pxa_addr_byte(i2c->msg), _IDBR(i2c));
699 	i2c->req_slave_addr = i2c_pxa_addr_byte(i2c->msg);
700 
701 	/*
702 	 * Step 2: initiate the write.
703 	 */
704 	icr = readl(_ICR(i2c)) & ~(ICR_STOP | ICR_ALDIE);
705 	writel(icr | ICR_START | ICR_TB, _ICR(i2c));
706 }
707 
708 static inline void i2c_pxa_stop_message(struct pxa_i2c *i2c)
709 {
710 	u32 icr;
711 
712 	/*
713 	 * Clear the STOP and ACK flags
714 	 */
715 	icr = readl(_ICR(i2c));
716 	icr &= ~(ICR_STOP | ICR_ACKNAK);
717 	writel(icr, _ICR(i2c));
718 }
719 
720 static int i2c_pxa_pio_set_master(struct pxa_i2c *i2c)
721 {
722 	/* make timeout the same as for interrupt based functions */
723 	long timeout = 2 * DEF_TIMEOUT;
724 
725 	/*
726 	 * Wait for the bus to become free.
727 	 */
728 	while (timeout-- && readl(_ISR(i2c)) & (ISR_IBB | ISR_UB)) {
729 		udelay(1000);
730 		show_state(i2c);
731 	}
732 
733 	if (timeout < 0) {
734 		show_state(i2c);
735 		dev_err(&i2c->adap.dev,
736 			"i2c_pxa: timeout waiting for bus free\n");
737 		return I2C_RETRY;
738 	}
739 
740 	/*
741 	 * Set master mode.
742 	 */
743 	writel(readl(_ICR(i2c)) | ICR_SCLE, _ICR(i2c));
744 
745 	return 0;
746 }
747 
748 /*
749  * PXA I2C send master code
750  * 1. Load master code to IDBR and send it.
751  *    Note for HS mode, set ICR [GPIOEN].
752  * 2. Wait until win arbitration.
753  */
754 static int i2c_pxa_send_mastercode(struct pxa_i2c *i2c)
755 {
756 	u32 icr;
757 	long timeout;
758 
759 	spin_lock_irq(&i2c->lock);
760 	i2c->highmode_enter = true;
761 	writel(i2c->master_code, _IDBR(i2c));
762 
763 	icr = readl(_ICR(i2c)) & ~(ICR_STOP | ICR_ALDIE);
764 	icr |= ICR_GPIOEN | ICR_START | ICR_TB | ICR_ITEIE;
765 	writel(icr, _ICR(i2c));
766 
767 	spin_unlock_irq(&i2c->lock);
768 	timeout = wait_event_timeout(i2c->wait,
769 			i2c->highmode_enter == false, HZ * 1);
770 
771 	i2c->highmode_enter = false;
772 
773 	return (timeout == 0) ? I2C_RETRY : 0;
774 }
775 
776 static int i2c_pxa_do_pio_xfer(struct pxa_i2c *i2c,
777 			       struct i2c_msg *msg, int num)
778 {
779 	unsigned long timeout = 500000; /* 5 seconds */
780 	int ret = 0;
781 
782 	ret = i2c_pxa_pio_set_master(i2c);
783 	if (ret)
784 		goto out;
785 
786 	i2c->msg = msg;
787 	i2c->msg_num = num;
788 	i2c->msg_idx = 0;
789 	i2c->msg_ptr = 0;
790 	i2c->irqlogidx = 0;
791 
792 	i2c_pxa_start_message(i2c);
793 
794 	while (i2c->msg_num > 0 && --timeout) {
795 		i2c_pxa_handler(0, i2c);
796 		udelay(10);
797 	}
798 
799 	i2c_pxa_stop_message(i2c);
800 
801 	/*
802 	 * We place the return code in i2c->msg_idx.
803 	 */
804 	ret = i2c->msg_idx;
805 
806 out:
807 	if (timeout == 0) {
808 		i2c_pxa_scream_blue_murder(i2c, "timeout");
809 		ret = I2C_RETRY;
810 	}
811 
812 	return ret;
813 }
814 
815 /*
816  * We are protected by the adapter bus mutex.
817  */
818 static int i2c_pxa_do_xfer(struct pxa_i2c *i2c, struct i2c_msg *msg, int num)
819 {
820 	long timeout;
821 	int ret;
822 
823 	/*
824 	 * Wait for the bus to become free.
825 	 */
826 	ret = i2c_pxa_wait_bus_not_busy(i2c);
827 	if (ret) {
828 		dev_err(&i2c->adap.dev, "i2c_pxa: timeout waiting for bus free\n");
829 		goto out;
830 	}
831 
832 	/*
833 	 * Set master mode.
834 	 */
835 	ret = i2c_pxa_set_master(i2c);
836 	if (ret) {
837 		dev_err(&i2c->adap.dev, "i2c_pxa_set_master: error %d\n", ret);
838 		goto out;
839 	}
840 
841 	if (i2c->high_mode) {
842 		ret = i2c_pxa_send_mastercode(i2c);
843 		if (ret) {
844 			dev_err(&i2c->adap.dev, "i2c_pxa_send_mastercode timeout\n");
845 			goto out;
846 			}
847 	}
848 
849 	spin_lock_irq(&i2c->lock);
850 
851 	i2c->msg = msg;
852 	i2c->msg_num = num;
853 	i2c->msg_idx = 0;
854 	i2c->msg_ptr = 0;
855 	i2c->irqlogidx = 0;
856 
857 	i2c_pxa_start_message(i2c);
858 
859 	spin_unlock_irq(&i2c->lock);
860 
861 	/*
862 	 * The rest of the processing occurs in the interrupt handler.
863 	 */
864 	timeout = wait_event_timeout(i2c->wait, i2c->msg_num == 0, HZ * 5);
865 	i2c_pxa_stop_message(i2c);
866 
867 	/*
868 	 * We place the return code in i2c->msg_idx.
869 	 */
870 	ret = i2c->msg_idx;
871 
872 	if (!timeout && i2c->msg_num) {
873 		i2c_pxa_scream_blue_murder(i2c, "timeout");
874 		ret = I2C_RETRY;
875 	}
876 
877  out:
878 	return ret;
879 }
880 
881 static int i2c_pxa_pio_xfer(struct i2c_adapter *adap,
882 			    struct i2c_msg msgs[], int num)
883 {
884 	struct pxa_i2c *i2c = adap->algo_data;
885 	int ret, i;
886 
887 	/* If the I2C controller is disabled we need to reset it
888 	  (probably due to a suspend/resume destroying state). We do
889 	  this here as we can then avoid worrying about resuming the
890 	  controller before its users. */
891 	if (!(readl(_ICR(i2c)) & ICR_IUE))
892 		i2c_pxa_reset(i2c);
893 
894 	for (i = adap->retries; i >= 0; i--) {
895 		ret = i2c_pxa_do_pio_xfer(i2c, msgs, num);
896 		if (ret != I2C_RETRY)
897 			goto out;
898 
899 		if (i2c_debug)
900 			dev_dbg(&adap->dev, "Retrying transmission\n");
901 		udelay(100);
902 	}
903 	i2c_pxa_scream_blue_murder(i2c, "exhausted retries");
904 	ret = -EREMOTEIO;
905  out:
906 	i2c_pxa_set_slave(i2c, ret);
907 	return ret;
908 }
909 
910 /*
911  * i2c_pxa_master_complete - complete the message and wake up.
912  */
913 static void i2c_pxa_master_complete(struct pxa_i2c *i2c, int ret)
914 {
915 	i2c->msg_ptr = 0;
916 	i2c->msg = NULL;
917 	i2c->msg_idx ++;
918 	i2c->msg_num = 0;
919 	if (ret)
920 		i2c->msg_idx = ret;
921 	if (!i2c->use_pio)
922 		wake_up(&i2c->wait);
923 }
924 
925 static void i2c_pxa_irq_txempty(struct pxa_i2c *i2c, u32 isr)
926 {
927 	u32 icr = readl(_ICR(i2c)) & ~(ICR_START|ICR_STOP|ICR_ACKNAK|ICR_TB);
928 
929  again:
930 	/*
931 	 * If ISR_ALD is set, we lost arbitration.
932 	 */
933 	if (isr & ISR_ALD) {
934 		/*
935 		 * Do we need to do anything here?  The PXA docs
936 		 * are vague about what happens.
937 		 */
938 		i2c_pxa_scream_blue_murder(i2c, "ALD set");
939 
940 		/*
941 		 * We ignore this error.  We seem to see spurious ALDs
942 		 * for seemingly no reason.  If we handle them as I think
943 		 * they should, we end up causing an I2C error, which
944 		 * is painful for some systems.
945 		 */
946 		return; /* ignore */
947 	}
948 
949 	if ((isr & ISR_BED) &&
950 		(!((i2c->msg->flags & I2C_M_IGNORE_NAK) &&
951 			(isr & ISR_ACKNAK)))) {
952 		int ret = BUS_ERROR;
953 
954 		/*
955 		 * I2C bus error - either the device NAK'd us, or
956 		 * something more serious happened.  If we were NAK'd
957 		 * on the initial address phase, we can retry.
958 		 */
959 		if (isr & ISR_ACKNAK) {
960 			if (i2c->msg_ptr == 0 && i2c->msg_idx == 0)
961 				ret = I2C_RETRY;
962 			else
963 				ret = XFER_NAKED;
964 		}
965 		i2c_pxa_master_complete(i2c, ret);
966 	} else if (isr & ISR_RWM) {
967 		/*
968 		 * Read mode.  We have just sent the address byte, and
969 		 * now we must initiate the transfer.
970 		 */
971 		if (i2c->msg_ptr == i2c->msg->len - 1 &&
972 		    i2c->msg_idx == i2c->msg_num - 1)
973 			icr |= ICR_STOP | ICR_ACKNAK;
974 
975 		icr |= ICR_ALDIE | ICR_TB;
976 	} else if (i2c->msg_ptr < i2c->msg->len) {
977 		/*
978 		 * Write mode.  Write the next data byte.
979 		 */
980 		writel(i2c->msg->buf[i2c->msg_ptr++], _IDBR(i2c));
981 
982 		icr |= ICR_ALDIE | ICR_TB;
983 
984 		/*
985 		 * If this is the last byte of the last message or last byte
986 		 * of any message with I2C_M_STOP (e.g. SCCB), send a STOP.
987 		 */
988 		if ((i2c->msg_ptr == i2c->msg->len) &&
989 			((i2c->msg->flags & I2C_M_STOP) ||
990 			(i2c->msg_idx == i2c->msg_num - 1)))
991 				icr |= ICR_STOP;
992 
993 	} else if (i2c->msg_idx < i2c->msg_num - 1) {
994 		/*
995 		 * Next segment of the message.
996 		 */
997 		i2c->msg_ptr = 0;
998 		i2c->msg_idx ++;
999 		i2c->msg++;
1000 
1001 		/*
1002 		 * If we aren't doing a repeated start and address,
1003 		 * go back and try to send the next byte.  Note that
1004 		 * we do not support switching the R/W direction here.
1005 		 */
1006 		if (i2c->msg->flags & I2C_M_NOSTART)
1007 			goto again;
1008 
1009 		/*
1010 		 * Write the next address.
1011 		 */
1012 		writel(i2c_pxa_addr_byte(i2c->msg), _IDBR(i2c));
1013 		i2c->req_slave_addr = i2c_pxa_addr_byte(i2c->msg);
1014 
1015 		/*
1016 		 * And trigger a repeated start, and send the byte.
1017 		 */
1018 		icr &= ~ICR_ALDIE;
1019 		icr |= ICR_START | ICR_TB;
1020 	} else {
1021 		if (i2c->msg->len == 0) {
1022 			/*
1023 			 * Device probes have a message length of zero
1024 			 * and need the bus to be reset before it can
1025 			 * be used again.
1026 			 */
1027 			i2c_pxa_reset(i2c);
1028 		}
1029 		i2c_pxa_master_complete(i2c, 0);
1030 	}
1031 
1032 	i2c->icrlog[i2c->irqlogidx-1] = icr;
1033 
1034 	writel(icr, _ICR(i2c));
1035 	show_state(i2c);
1036 }
1037 
1038 static void i2c_pxa_irq_rxfull(struct pxa_i2c *i2c, u32 isr)
1039 {
1040 	u32 icr = readl(_ICR(i2c)) & ~(ICR_START|ICR_STOP|ICR_ACKNAK|ICR_TB);
1041 
1042 	/*
1043 	 * Read the byte.
1044 	 */
1045 	i2c->msg->buf[i2c->msg_ptr++] = readl(_IDBR(i2c));
1046 
1047 	if (i2c->msg_ptr < i2c->msg->len) {
1048 		/*
1049 		 * If this is the last byte of the last
1050 		 * message, send a STOP.
1051 		 */
1052 		if (i2c->msg_ptr == i2c->msg->len - 1)
1053 			icr |= ICR_STOP | ICR_ACKNAK;
1054 
1055 		icr |= ICR_ALDIE | ICR_TB;
1056 	} else {
1057 		i2c_pxa_master_complete(i2c, 0);
1058 	}
1059 
1060 	i2c->icrlog[i2c->irqlogidx-1] = icr;
1061 
1062 	writel(icr, _ICR(i2c));
1063 }
1064 
1065 #define VALID_INT_SOURCE	(ISR_SSD | ISR_ALD | ISR_ITE | ISR_IRF | \
1066 				ISR_SAD | ISR_BED)
1067 static irqreturn_t i2c_pxa_handler(int this_irq, void *dev_id)
1068 {
1069 	struct pxa_i2c *i2c = dev_id;
1070 	u32 isr = readl(_ISR(i2c));
1071 
1072 	if (!(isr & VALID_INT_SOURCE))
1073 		return IRQ_NONE;
1074 
1075 	if (i2c_debug > 2 && 0) {
1076 		dev_dbg(&i2c->adap.dev, "%s: ISR=%08x, ICR=%08x, IBMR=%02x\n",
1077 			__func__, isr, readl(_ICR(i2c)), readl(_IBMR(i2c)));
1078 		decode_ISR(isr);
1079 	}
1080 
1081 	if (i2c->irqlogidx < ARRAY_SIZE(i2c->isrlog))
1082 		i2c->isrlog[i2c->irqlogidx++] = isr;
1083 
1084 	show_state(i2c);
1085 
1086 	/*
1087 	 * Always clear all pending IRQs.
1088 	 */
1089 	writel(isr & VALID_INT_SOURCE, _ISR(i2c));
1090 
1091 	if (isr & ISR_SAD)
1092 		i2c_pxa_slave_start(i2c, isr);
1093 	if (isr & ISR_SSD)
1094 		i2c_pxa_slave_stop(i2c);
1095 
1096 	if (i2c_pxa_is_slavemode(i2c)) {
1097 		if (isr & ISR_ITE)
1098 			i2c_pxa_slave_txempty(i2c, isr);
1099 		if (isr & ISR_IRF)
1100 			i2c_pxa_slave_rxfull(i2c, isr);
1101 	} else if (i2c->msg && (!i2c->highmode_enter)) {
1102 		if (isr & ISR_ITE)
1103 			i2c_pxa_irq_txempty(i2c, isr);
1104 		if (isr & ISR_IRF)
1105 			i2c_pxa_irq_rxfull(i2c, isr);
1106 	} else if ((isr & ISR_ITE) && i2c->highmode_enter) {
1107 		i2c->highmode_enter = false;
1108 		wake_up(&i2c->wait);
1109 	} else {
1110 		i2c_pxa_scream_blue_murder(i2c, "spurious irq");
1111 	}
1112 
1113 	return IRQ_HANDLED;
1114 }
1115 
1116 
1117 static int i2c_pxa_xfer(struct i2c_adapter *adap, struct i2c_msg msgs[], int num)
1118 {
1119 	struct pxa_i2c *i2c = adap->algo_data;
1120 	int ret, i;
1121 
1122 	for (i = adap->retries; i >= 0; i--) {
1123 		ret = i2c_pxa_do_xfer(i2c, msgs, num);
1124 		if (ret != I2C_RETRY)
1125 			goto out;
1126 
1127 		if (i2c_debug)
1128 			dev_dbg(&adap->dev, "Retrying transmission\n");
1129 		udelay(100);
1130 	}
1131 	i2c_pxa_scream_blue_murder(i2c, "exhausted retries");
1132 	ret = -EREMOTEIO;
1133  out:
1134 	i2c_pxa_set_slave(i2c, ret);
1135 	return ret;
1136 }
1137 
1138 static u32 i2c_pxa_functionality(struct i2c_adapter *adap)
1139 {
1140 	return I2C_FUNC_I2C | I2C_FUNC_SMBUS_EMUL |
1141 		I2C_FUNC_PROTOCOL_MANGLING | I2C_FUNC_NOSTART;
1142 }
1143 
1144 static const struct i2c_algorithm i2c_pxa_algorithm = {
1145 	.master_xfer	= i2c_pxa_xfer,
1146 	.functionality	= i2c_pxa_functionality,
1147 };
1148 
1149 static const struct i2c_algorithm i2c_pxa_pio_algorithm = {
1150 	.master_xfer	= i2c_pxa_pio_xfer,
1151 	.functionality	= i2c_pxa_functionality,
1152 };
1153 
1154 static const struct of_device_id i2c_pxa_dt_ids[] = {
1155 	{ .compatible = "mrvl,pxa-i2c", .data = (void *)REGS_PXA2XX },
1156 	{ .compatible = "mrvl,pwri2c", .data = (void *)REGS_PXA3XX },
1157 	{ .compatible = "mrvl,mmp-twsi", .data = (void *)REGS_PXA910 },
1158 	{ .compatible = "marvell,armada-3700-i2c", .data = (void *)REGS_A3700 },
1159 	{}
1160 };
1161 MODULE_DEVICE_TABLE(of, i2c_pxa_dt_ids);
1162 
1163 static int i2c_pxa_probe_dt(struct platform_device *pdev, struct pxa_i2c *i2c,
1164 			    enum pxa_i2c_types *i2c_types)
1165 {
1166 	struct device_node *np = pdev->dev.of_node;
1167 	const struct of_device_id *of_id =
1168 			of_match_device(i2c_pxa_dt_ids, &pdev->dev);
1169 
1170 	if (!of_id)
1171 		return 1;
1172 
1173 	/* For device tree we always use the dynamic or alias-assigned ID */
1174 	i2c->adap.nr = -1;
1175 
1176 	if (of_get_property(np, "mrvl,i2c-polling", NULL))
1177 		i2c->use_pio = 1;
1178 	if (of_get_property(np, "mrvl,i2c-fast-mode", NULL))
1179 		i2c->fast_mode = 1;
1180 
1181 	*i2c_types = (enum pxa_i2c_types)(of_id->data);
1182 
1183 	return 0;
1184 }
1185 
1186 static int i2c_pxa_probe_pdata(struct platform_device *pdev,
1187 			       struct pxa_i2c *i2c,
1188 			       enum pxa_i2c_types *i2c_types)
1189 {
1190 	struct i2c_pxa_platform_data *plat = dev_get_platdata(&pdev->dev);
1191 	const struct platform_device_id *id = platform_get_device_id(pdev);
1192 
1193 	*i2c_types = id->driver_data;
1194 	if (plat) {
1195 		i2c->use_pio = plat->use_pio;
1196 		i2c->fast_mode = plat->fast_mode;
1197 		i2c->high_mode = plat->high_mode;
1198 		i2c->master_code = plat->master_code;
1199 		if (!i2c->master_code)
1200 			i2c->master_code = 0xe;
1201 		i2c->rate = plat->rate;
1202 	}
1203 	return 0;
1204 }
1205 
1206 static int i2c_pxa_probe(struct platform_device *dev)
1207 {
1208 	struct i2c_pxa_platform_data *plat = dev_get_platdata(&dev->dev);
1209 	enum pxa_i2c_types i2c_type;
1210 	struct pxa_i2c *i2c;
1211 	struct resource *res = NULL;
1212 	int ret, irq;
1213 
1214 	i2c = devm_kzalloc(&dev->dev, sizeof(struct pxa_i2c), GFP_KERNEL);
1215 	if (!i2c)
1216 		return -ENOMEM;
1217 
1218 	res = platform_get_resource(dev, IORESOURCE_MEM, 0);
1219 	i2c->reg_base = devm_ioremap_resource(&dev->dev, res);
1220 	if (IS_ERR(i2c->reg_base))
1221 		return PTR_ERR(i2c->reg_base);
1222 
1223 	irq = platform_get_irq(dev, 0);
1224 	if (irq < 0) {
1225 		dev_err(&dev->dev, "no irq resource: %d\n", irq);
1226 		return irq;
1227 	}
1228 
1229 	/* Default adapter num to device id; i2c_pxa_probe_dt can override. */
1230 	i2c->adap.nr = dev->id;
1231 
1232 	ret = i2c_pxa_probe_dt(dev, i2c, &i2c_type);
1233 	if (ret > 0)
1234 		ret = i2c_pxa_probe_pdata(dev, i2c, &i2c_type);
1235 	if (ret < 0)
1236 		return ret;
1237 
1238 	i2c->adap.owner   = THIS_MODULE;
1239 	i2c->adap.retries = 5;
1240 
1241 	spin_lock_init(&i2c->lock);
1242 	init_waitqueue_head(&i2c->wait);
1243 
1244 	strlcpy(i2c->adap.name, "pxa_i2c-i2c", sizeof(i2c->adap.name));
1245 
1246 	i2c->clk = devm_clk_get(&dev->dev, NULL);
1247 	if (IS_ERR(i2c->clk)) {
1248 		dev_err(&dev->dev, "failed to get the clk: %ld\n", PTR_ERR(i2c->clk));
1249 		return PTR_ERR(i2c->clk);
1250 	}
1251 
1252 	i2c->reg_ibmr = i2c->reg_base + pxa_reg_layout[i2c_type].ibmr;
1253 	i2c->reg_idbr = i2c->reg_base + pxa_reg_layout[i2c_type].idbr;
1254 	i2c->reg_icr = i2c->reg_base + pxa_reg_layout[i2c_type].icr;
1255 	i2c->reg_isr = i2c->reg_base + pxa_reg_layout[i2c_type].isr;
1256 	i2c->fm_mask = pxa_reg_layout[i2c_type].fm ? : ICR_FM;
1257 	i2c->hs_mask = pxa_reg_layout[i2c_type].hs ? : ICR_HS;
1258 
1259 	if (i2c_type != REGS_CE4100)
1260 		i2c->reg_isar = i2c->reg_base + pxa_reg_layout[i2c_type].isar;
1261 
1262 	if (i2c_type == REGS_PXA910) {
1263 		i2c->reg_ilcr = i2c->reg_base + pxa_reg_layout[i2c_type].ilcr;
1264 		i2c->reg_iwcr = i2c->reg_base + pxa_reg_layout[i2c_type].iwcr;
1265 	}
1266 
1267 	i2c->iobase = res->start;
1268 	i2c->iosize = resource_size(res);
1269 
1270 	i2c->irq = irq;
1271 
1272 	i2c->slave_addr = I2C_PXA_SLAVE_ADDR;
1273 	i2c->highmode_enter = false;
1274 
1275 	if (plat) {
1276 #ifdef CONFIG_I2C_PXA_SLAVE
1277 		i2c->slave_addr = plat->slave_addr;
1278 		i2c->slave = plat->slave;
1279 #endif
1280 		i2c->adap.class = plat->class;
1281 	}
1282 
1283 	if (i2c->high_mode) {
1284 		if (i2c->rate) {
1285 			clk_set_rate(i2c->clk, i2c->rate);
1286 			pr_info("i2c: <%s> set rate to %ld\n",
1287 				i2c->adap.name, clk_get_rate(i2c->clk));
1288 		} else
1289 			pr_warn("i2c: <%s> clock rate not set\n",
1290 				i2c->adap.name);
1291 	}
1292 
1293 	clk_prepare_enable(i2c->clk);
1294 
1295 	if (i2c->use_pio) {
1296 		i2c->adap.algo = &i2c_pxa_pio_algorithm;
1297 	} else {
1298 		i2c->adap.algo = &i2c_pxa_algorithm;
1299 		ret = devm_request_irq(&dev->dev, irq, i2c_pxa_handler,
1300 				IRQF_SHARED | IRQF_NO_SUSPEND,
1301 				dev_name(&dev->dev), i2c);
1302 		if (ret) {
1303 			dev_err(&dev->dev, "failed to request irq: %d\n", ret);
1304 			goto ereqirq;
1305 		}
1306 	}
1307 
1308 	i2c_pxa_reset(i2c);
1309 
1310 	i2c->adap.algo_data = i2c;
1311 	i2c->adap.dev.parent = &dev->dev;
1312 #ifdef CONFIG_OF
1313 	i2c->adap.dev.of_node = dev->dev.of_node;
1314 #endif
1315 
1316 	ret = i2c_add_numbered_adapter(&i2c->adap);
1317 	if (ret < 0)
1318 		goto ereqirq;
1319 
1320 	platform_set_drvdata(dev, i2c);
1321 
1322 #ifdef CONFIG_I2C_PXA_SLAVE
1323 	dev_info(&i2c->adap.dev, " PXA I2C adapter, slave address %d\n",
1324 		i2c->slave_addr);
1325 #else
1326 	dev_info(&i2c->adap.dev, " PXA I2C adapter\n");
1327 #endif
1328 	return 0;
1329 
1330 ereqirq:
1331 	clk_disable_unprepare(i2c->clk);
1332 	return ret;
1333 }
1334 
1335 static int i2c_pxa_remove(struct platform_device *dev)
1336 {
1337 	struct pxa_i2c *i2c = platform_get_drvdata(dev);
1338 
1339 	i2c_del_adapter(&i2c->adap);
1340 
1341 	clk_disable_unprepare(i2c->clk);
1342 
1343 	return 0;
1344 }
1345 
1346 #ifdef CONFIG_PM
1347 static int i2c_pxa_suspend_noirq(struct device *dev)
1348 {
1349 	struct pxa_i2c *i2c = dev_get_drvdata(dev);
1350 
1351 	clk_disable(i2c->clk);
1352 
1353 	return 0;
1354 }
1355 
1356 static int i2c_pxa_resume_noirq(struct device *dev)
1357 {
1358 	struct pxa_i2c *i2c = dev_get_drvdata(dev);
1359 
1360 	clk_enable(i2c->clk);
1361 	i2c_pxa_reset(i2c);
1362 
1363 	return 0;
1364 }
1365 
1366 static const struct dev_pm_ops i2c_pxa_dev_pm_ops = {
1367 	.suspend_noirq = i2c_pxa_suspend_noirq,
1368 	.resume_noirq = i2c_pxa_resume_noirq,
1369 };
1370 
1371 #define I2C_PXA_DEV_PM_OPS (&i2c_pxa_dev_pm_ops)
1372 #else
1373 #define I2C_PXA_DEV_PM_OPS NULL
1374 #endif
1375 
1376 static struct platform_driver i2c_pxa_driver = {
1377 	.probe		= i2c_pxa_probe,
1378 	.remove		= i2c_pxa_remove,
1379 	.driver		= {
1380 		.name	= "pxa2xx-i2c",
1381 		.pm	= I2C_PXA_DEV_PM_OPS,
1382 		.of_match_table = i2c_pxa_dt_ids,
1383 	},
1384 	.id_table	= i2c_pxa_id_table,
1385 };
1386 
1387 static int __init i2c_adap_pxa_init(void)
1388 {
1389 	return platform_driver_register(&i2c_pxa_driver);
1390 }
1391 
1392 static void __exit i2c_adap_pxa_exit(void)
1393 {
1394 	platform_driver_unregister(&i2c_pxa_driver);
1395 }
1396 
1397 MODULE_LICENSE("GPL");
1398 MODULE_ALIAS("platform:pxa2xx-i2c");
1399 
1400 subsys_initcall(i2c_adap_pxa_init);
1401 module_exit(i2c_adap_pxa_exit);
1402