summaryrefslogtreecommitdiffstats
path: root/drivers/base/regmap/regmap.c
blob: bb80853ff27a9d25e1003a25edec0d21cbe8c2ad (plain)
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
202
203
204
205
206
207
208
209
210
211
212
213
214
215
216
217
218
219
220
221
222
223
224
225
226
227
228
229
230
231
232
233
234
235
236
237
238
239
240
241
242
243
244
245
246
247
248
249
250
251
252
253
254
255
256
257
258
259
260
261
262
263
264
265
266
267
268
269
270
271
272
273
274
275
276
277
278
279
280
281
282
283
284
285
286
287
288
289
290
291
292
293
294
295
296
297
298
299
300
301
302
303
304
305
306
307
308
309
310
311
312
313
314
315
316
317
318
319
320
321
322
323
324
325
326
327
328
329
330
331
332
333
334
335
336
337
338
339
340
341
342
343
344
345
346
347
348
349
350
351
352
353
354
355
356
357
358
359
360
361
362
363
364
365
366
367
368
369
370
371
372
373
374
375
376
377
378
379
380
381
382
383
384
385
386
387
388
389
390
391
392
393
394
395
396
397
398
399
400
401
402
403
404
405
406
407
408
409
410
411
412
413
414
415
416
417
418
419
420
421
422
423
424
425
426
427
428
429
430
431
432
433
434
435
436
437
438
439
440
441
442
443
444
445
446
447
448
449
450
451
452
453
454
455
456
457
458
459
460
461
462
463
464
465
466
467
468
469
470
471
472
473
474
475
476
477
478
479
480
481
482
483
484
485
486
487
488
489
490
491
492
493
494
495
496
497
498
499
500
501
502
503
504
505
506
507
508
509
510
511
512
513
514
515
516
517
518
519
520
521
522
523
524
525
526
527
528
529
530
531
532
533
534
535
536
537
538
539
540
541
542
543
544
545
546
547
548
549
550
551
552
553
554
555
556
557
558
559
560
561
562
563
564
565
566
567
568
569
570
571
572
573
574
575
576
577
578
579
580
581
582
583
584
585
586
587
588
589
590
591
592
593
594
595
596
597
598
599
600
601
602
603
604
605
606
607
608
609
610
611
612
613
614
615
616
617
618
619
620
621
622
623
624
625
626
627
628
629
630
631
632
633
634
635
636
637
638
639
640
641
642
643
644
645
646
647
648
649
650
651
652
653
654
655
656
657
658
659
660
661
662
663
664
665
666
667
668
669
670
671
672
673
674
675
676
677
678
679
680
681
682
683
684
685
686
687
688
689
690
691
692
693
694
695
696
697
698
699
700
701
702
703
704
705
706
707
708
709
710
711
712
713
714
715
716
717
718
719
720
721
722
723
724
725
726
727
728
729
730
731
732
733
734
735
736
737
738
739
740
741
742
743
744
745
746
747
748
749
750
751
752
753
754
755
756
757
758
759
760
761
762
763
764
765
766
767
768
769
770
771
772
773
774
775
776
777
778
779
780
781
782
783
784
785
786
787
788
789
790
791
792
793
794
795
796
797
798
799
800
801
802
803
804
805
806
807
808
809
810
811
812
813
814
815
816
817
818
819
820
821
822
823
824
825
826
827
828
829
830
831
832
833
834
835
836
837
838
839
840
841
842
843
844
845
846
847
848
849
850
851
852
853
854
855
856
857
858
859
860
861
862
863
864
865
866
867
868
869
870
871
872
873
874
875
876
877
878
879
880
881
882
883
884
885
886
887
888
889
890
891
892
893
894
895
896
897
898
899
900
901
902
903
904
905
906
907
908
909
910
911
912
913
914
915
916
917
918
919
920
921
922
923
924
925
926
927
928
929
930
931
932
933
934
935
936
/*
 * Register map access API
 *
 * Copyright 2011 Wolfson Microelectronics plc
 *
 * Author: Mark Brown <broonie@opensource.wolfsonmicro.com>
 *
 * This program is free software; you can redistribute it and/or modify
 * it under the terms of the GNU General Public License version 2 as
 * published by the Free Software Foundation.
 */

#include <linux/device.h>
#include <linux/slab.h>
#include <linux/export.h>
#include <linux/mutex.h>
#include <linux/err.h>

#define CREATE_TRACE_POINTS
#include <trace/events/regmap.h>

#include "internal.h"

bool regmap_writeable(struct regmap *map, unsigned int reg)
{
	if (map->max_register && reg > map->max_register)
		return false;

	if (map->writeable_reg)
		return map->writeable_reg(map->dev, reg);

	return true;
}

bool regmap_readable(struct regmap *map, unsigned int reg)
{
	if (map->max_register && reg > map->max_register)
		return false;

	if (map->format.format_write)
		return false;

	if (map->readable_reg)
		return map->readable_reg(map->dev, reg);

	return true;
}

bool regmap_volatile(struct regmap *map, unsigned int reg)
{
	if (!regmap_readable(map, reg))
		return false;

	if (map->volatile_reg)
		return map->volatile_reg(map->dev, reg);

	return true;
}

bool regmap_precious(struct regmap *map, unsigned int reg)
{
	if (!regmap_readable(map, reg))
		return false;

	if (map->precious_reg)
		return map->precious_reg(map->dev, reg);

	return false;
}

static bool regmap_volatile_range(struct regmap *map, unsigned int reg,
	unsigned int num)
{
	unsigned int i;

	for (i = 0; i < num; i++)
		if (!regmap_volatile(map, reg + i))
			return false;

	return true;
}

static void regmap_format_2_6_write(struct regmap *map,
				     unsigned int reg, unsigned int val)
{
	u8 *out = map->work_buf;

	*out = (reg << 6) | val;
}

static void regmap_format_4_12_write(struct regmap *map,
				     unsigned int reg, unsigned int val)
{
	__be16 *out = map->work_buf;
	*out = cpu_to_be16((reg << 12) | val);
}

static void regmap_format_7_9_write(struct regmap *map,
				    unsigned int reg, unsigned int val)
{
	__be16 *out = map->work_buf;
	*out = cpu_to_be16((reg << 9) | val);
}

static void regmap_format_10_14_write(struct regmap *map,
				    unsigned int reg, unsigned int val)
{
	u8 *out = map->work_buf;

	out[2] = val;
	out[1] = (val >> 8) | (reg << 6);
	out[0] = reg >> 2;
}

static void regmap_format_8(void *buf, unsigned int val)
{
	u8 *b = buf;

	b[0] = val;
}

static void regmap_format_16(void *buf, unsigned int val)
{
	__be16 *b = buf;

	b[0] = cpu_to_be16(val);
}

static void regmap_format_32(void *buf, unsigned int val)
{
	__be32 *b = buf;

	b[0] = cpu_to_be32(val);
}

static unsigned int regmap_parse_8(void *buf)
{
	u8 *b = buf;

	return b[0];
}

static unsigned int regmap_parse_16(void *buf)
{
	__be16 *b = buf;

	b[0] = be16_to_cpu(b[0]);

	return b[0];
}

static unsigned int regmap_parse_32(void *buf)
{
	__be32 *b = buf;

	b[0] = be32_to_cpu(b[0]);

	return b[0];
}

/**
 * regmap_init(): Initialise register map
 *
 * @dev: Device that will be interacted with
 * @bus: Bus-specific callbacks to use with device
 * @config: Configuration for register map
 *
 * The return value will be an ERR_PTR() on error or a valid pointer to
 * a struct regmap.  This function should generally not be called
 * directly, it should be called by bus-specific init functions.
 */
struct regmap *regmap_init(struct device *dev,
			   const struct regmap_bus *bus,
			   const struct regmap_config *config)
{
	struct regmap *map;
	int ret = -EINVAL;

	if (!bus || !config)
		goto err;

	map = kzalloc(sizeof(*map), GFP_KERNEL);
	if (map == NULL) {
		ret = -ENOMEM;
		goto err;
	}

	mutex_init(&map->lock);
	map->format.buf_size = (config->reg_bits + config->val_bits) / 8;
	map->format.reg_bytes = DIV_ROUND_UP(config->reg_bits, 8);
	map->format.pad_bytes = config->pad_bits / 8;
	map->format.val_bytes = DIV_ROUND_UP(config->val_bits, 8);
	map->format.buf_size += map->format.pad_bytes;
	map->dev = dev;
	map->bus = bus;
	map->max_register = config->max_register;
	map->writeable_reg = config->writeable_reg;
	map->readable_reg = config->readable_reg;
	map->volatile_reg = config->volatile_reg;
	map->precious_reg = config->precious_reg;
	map->cache_type = config->cache_type;

	if (config->read_flag_mask || config->write_flag_mask) {
		map->read_flag_mask = config->read_flag_mask;
		map->write_flag_mask = config->write_flag_mask;
	} else {
		map->read_flag_mask = bus->read_flag_mask;
	}

	switch (config->reg_bits) {
	case 2:
		switch (config->val_bits) {
		case 6:
			map->format.format_write = regmap_format_2_6_write;
			break;
		default:
			goto err_map;
		}
		break;

	case 4:
		switch (config->val_bits) {
		case 12:
			map->format.format_write = regmap_format_4_12_write;
			break;
		default:
			goto err_map;
		}
		break;

	case 7:
		switch (config->val_bits) {
		case 9:
			map->format.format_write = regmap_format_7_9_write;
			break;
		default:
			goto err_map;
		}
		break;

	case 10:
		switch (config->val_bits) {
		case 14:
			map->format.format_write = regmap_format_10_14_write;
			break;
		default:
			goto err_map;
		}
		break;

	case 8:
		map->format.format_reg = regmap_format_8;
		break;

	case 16:
		map->format.format_reg = regmap_format_16;
		break;

	case 32:
		map->format.format_reg = regmap_format_32;
		break;

	default:
		goto err_map;
	}

	switch (config->val_bits) {
	case 8:
		map->format.format_val = regmap_format_8;
		map->format.parse_val = regmap_parse_8;
		break;
	case 16:
		map->format.format_val = regmap_format_16;
		map->format.parse_val = regmap_parse_16;
		break;
	case 32:
		map->format.format_val = regmap_format_32;
		map->format.parse_val = regmap_parse_32;
		break;
	}

	if (!map->format.format_write &&
	    !(map->format.format_reg && map->format.format_val))
		goto err_map;

	map->work_buf = kzalloc(map->format.buf_size, GFP_KERNEL);
	if (map->work_buf == NULL) {
		ret = -ENOMEM;
		goto err_map;
	}

	regmap_debugfs_init(map);

	ret = regcache_init(map, config);
	if (ret < 0)
		goto err_free_workbuf;

	return map;

err_free_workbuf:
	kfree(map->work_buf);
err_map:
	kfree(map);
err:
	return ERR_PTR(ret);
}
EXPORT_SYMBOL_GPL(regmap_init);

static void devm_regmap_release(struct device *dev, void *res)
{
	regmap_exit(*(struct regmap **)res);
}

/**
 * devm_regmap_init(): Initialise managed register map
 *
 * @dev: Device that will be interacted with
 * @bus: Bus-specific callbacks to use with device
 * @config: Configuration for register map
 *
 * The return value will be an ERR_PTR() on error or a valid pointer
 * to a struct regmap.  This function should generally not be called
 * directly, it should be called by bus-specific init functions.  The
 * map will be automatically freed by the device management code.
 */
struct regmap *devm_regmap_init(struct device *dev,
				const struct regmap_bus *bus,
				const struct regmap_config *config)
{
	struct regmap **ptr, *regmap;

	ptr = devres_alloc(devm_regmap_release, sizeof(*ptr), GFP_KERNEL);
	if (!ptr)
		return ERR_PTR(-ENOMEM);

	regmap = regmap_init(dev, bus, config);
	if (!IS_ERR(regmap)) {
		*ptr = regmap;
		devres_add(dev, ptr);
	} else {
		devres_free(ptr);
	}

	return regmap;
}
EXPORT_SYMBOL_GPL(devm_regmap_init);

/**
 * regmap_reinit_cache(): Reinitialise the current register cache
 *
 * @map: Register map to operate on.
 * @config: New configuration.  Only the cache data will be used.
 *
 * Discard any existing register cache for the map and initialize a
 * new cache.  This can be used to restore the cache to defaults or to
 * update the cache configuration to reflect runtime discovery of the
 * hardware.
 */
int regmap_reinit_cache(struct regmap *map, const struct regmap_config *config)
{
	int ret;

	mutex_lock(&map->lock);

	regcache_exit(map);
	regmap_debugfs_exit(map);

	map->max_register = config->max_register;
	map->writeable_reg = config->writeable_reg;
	map->readable_reg = config->readable_reg;
	map->volatile_reg = config->volatile_reg;
	map->precious_reg = config->precious_reg;
	map->cache_type = config->cache_type;

	regmap_debugfs_init(map);

	map->cache_bypass = false;
	map->cache_only = false;

	ret = regcache_init(map, config);

	mutex_unlock(&map->lock);

	return ret;
}

/**
 * regmap_exit(): Free a previously allocated register map
 */
void regmap_exit(struct regmap *map)
{
	regcache_exit(map);
	regmap_debugfs_exit(map);
	kfree(map->work_buf);
	kfree(map);
}
EXPORT_SYMBOL_GPL(regmap_exit);

static int _regmap_raw_write(struct regmap *map, unsigned int reg,
			     const void *val, size_t val_len)
{
	u8 *u8 = map->work_buf;
	void *buf;
	int ret = -ENOTSUPP;
	size_t len;
	int i;

	/* Check for unwritable registers before we start */
	if (map->writeable_reg)
		for (i = 0; i < val_len / map->format.val_bytes; i++)
			if (!map->writeable_reg(map->dev, reg + i))
				return -EINVAL;

	if (!map->cache_bypass && map->format.parse_val) {
		unsigned int ival;
		int val_bytes = map->format.val_bytes;
		for (i = 0; i < val_len / val_bytes; i++) {
			memcpy(map->work_buf, val + (i * val_bytes), val_bytes);
			ival = map->format.parse_val(map->work_buf);
			ret = regcache_write(map, reg + i, ival);
			if (ret) {
				dev_err(map->dev,
				   "Error in caching of register: %u ret: %d\n",
					reg + i, ret);
				return ret;
			}
		}
		if (map->cache_only) {
			map->cache_dirty = true;
			return 0;
		}
	}

	map->format.format_reg(map->work_buf, reg);

	u8[0] |= map->write_flag_mask;

	trace_regmap_hw_write_start(map->dev, reg,
				    val_len / map->format.val_bytes);

	/* If we're doing a single register write we can probably just
	 * send the work_buf directly, otherwise try to do a gather
	 * write.
	 */
	if (val == (map->work_buf + map->format.pad_bytes +
		    map->format.reg_bytes))
		ret = map->bus->write(map->dev, map->work_buf,
				      map->format.reg_bytes +
				      map->format.pad_bytes +
				      val_len);
	else if (map->bus->gather_write)
		ret = map->bus->gather_write(map->dev, map->work_buf,
					     map->format.reg_bytes +
					     map->format.pad_bytes,
					     val, val_len);

	/* If that didn't work fall back on linearising by hand. */
	if (ret == -ENOTSUPP) {
		len = map->format.reg_bytes + map->format.pad_bytes + val_len;
		buf = kzalloc(len, GFP_KERNEL);
		if (!buf)
			return -ENOMEM;

		memcpy(buf, map->work_buf, map->format.reg_bytes);
		memcpy(buf + map->format.reg_bytes + map->format.pad_bytes,
		       val, val_len);
		ret = map->bus->write(map->dev, buf, len);

		kfree(buf);
	}

	trace_regmap_hw_write_done(map->dev, reg,
				   val_len / map->format.val_bytes);

	return ret;
}

int _regmap_write(struct regmap *map, unsigned int reg,
		  unsigned int val)
{
	int ret;
	BUG_ON(!map->format.format_write && !map->format.format_val);

	if (!map->cache_bypass && map->format.format_write) {
		ret = regcache_write(map, reg, val);
		if (ret != 0)
			return ret;
		if (map->cache_only) {
			map->cache_dirty = true;
			return 0;
		}
	}

	trace_regmap_reg_write(map->dev, reg, val);

	if (map->format.format_write) {
		map->format.format_write(map, reg, val);

		trace_regmap_hw_write_start(map->dev, reg, 1);

		ret = map->bus->write(map->dev, map->work_buf,
				      map->format.buf_size);

		trace_regmap_hw_write_done(map->dev, reg, 1);

		return ret;
	} else {
		map->format.format_val(map->work_buf + map->format.reg_bytes
				       + map->format.pad_bytes, val);
		return _regmap_raw_write(map, reg,
					 map->work_buf +
					 map->format.reg_bytes +
					 map->format.pad_bytes,
					 map->format.val_bytes);
	}
}

/**
 * regmap_write(): Write a value to a single register
 *
 * @map: Register map to write to
 * @reg: Register to write to
 * @val: Value to be written
 *
 * A value of zero will be returned on success, a negative errno will
 * be returned in error cases.
 */
int regmap_write(struct regmap *map, unsigned int reg, unsigned int val)
{
	int ret;

	mutex_lock(&map->lock);

	ret = _regmap_write(map, reg, val);

	mutex_unlock(&map->lock);

	return ret;
}
EXPORT_SYMBOL_GPL(regmap_write);

/**
 * regmap_raw_write(): Write raw values to one or more registers
 *
 * @map: Register map to write to
 * @reg: Initial register to write to
 * @val: Block of data to be written, laid out for direct transmission to the
 *       device
 * @val_len: Length of data pointed to by val.
 *
 * This function is intended to be used for things like firmware
 * download where a large block of data needs to be transferred to the
 * device.  No formatting will be done on the data provided.
 *
 * A value of zero will be returned on success, a negative errno will
 * be returned in error cases.
 */
int regmap_raw_write(struct regmap *map, unsigned int reg,
		     const void *val, size_t val_len)
{
	int ret;

	mutex_lock(&map->lock);

	ret = _regmap_raw_write(map, reg, val, val_len);

	mutex_unlock(&map->lock);

	return ret;
}
EXPORT_SYMBOL_GPL(regmap_raw_write);

/*
 * regmap_bulk_write(): Write multiple registers to the device
 *
 * @map: Register map to write to
 * @reg: First register to be write from
 * @val: Block of data to be written, in native register size for device
 * @val_count: Number of registers to write
 *
 * This function is intended to be used for writing a large block of
 * data to be device either in single transfer or multiple transfer.
 *
 * A value of zero will be returned on success, a negative errno will
 * be returned in error cases.
 */
int regmap_bulk_write(struct regmap *map, unsigned int reg, const void *val,
		     size_t val_count)
{
	int ret = 0, i;
	size_t val_bytes = map->format.val_bytes;
	void *wval;

	if (!map->format.parse_val)
		return -EINVAL;

	mutex_lock(&map->lock);

	/* No formatting is require if val_byte is 1 */
	if (val_bytes == 1) {
		wval = (void *)val;
	} else {
		wval = kmemdup(val, val_count * val_bytes, GFP_KERNEL);
		if (!wval) {
			ret = -ENOMEM;
			dev_err(map->dev, "Error in memory allocation\n");
			goto out;
		}
		for (i = 0; i < val_count * val_bytes; i += val_bytes)
			map->format.parse_val(wval + i);
	}
	ret = _regmap_raw_write(map, reg, wval, val_bytes * val_count);

	if (val_bytes != 1)
		kfree(wval);

out:
	mutex_unlock(&map->lock);
	return ret;
}
EXPORT_SYMBOL_GPL(regmap_bulk_write);

static int _regmap_raw_read(struct regmap *map, unsigned int reg, void *val,
			    unsigned int val_len)
{
	u8 *u8 = map->work_buf;
	int ret;

	map->format.format_reg(map->work_buf, reg);

	/*
	 * Some buses or devices flag reads by setting the high bits in the
	 * register addresss; since it's always the high bits for all
	 * current formats we can do this here rather than in
	 * formatting.  This may break if we get interesting formats.
	 */
	u8[0] |= map->read_flag_mask;

	trace_regmap_hw_read_start(map->dev, reg,
				   val_len / map->format.val_bytes);

	ret = map->bus->read(map->dev, map->work_buf,
			     map->format.reg_bytes + map->format.pad_bytes,
			     val, val_len);

	trace_regmap_hw_read_done(map->dev, reg,
				  val_len / map->format.val_bytes);

	return ret;
}

static int _regmap_read(struct regmap *map, unsigned int reg,
			unsigned int *val)
{
	int ret;

	if (!map->cache_bypass) {
		ret = regcache_read(map, reg, val);
		if (ret == 0)
			return 0;
	}

	if (!map->format.parse_val)
		return -EINVAL;

	if (map->cache_only)
		return -EBUSY;

	ret = _regmap_raw_read(map, reg, map->work_buf, map->format.val_bytes);
	if (ret == 0) {
		*val = map->format.parse_val(map->work_buf);
		trace_regmap_reg_read(map->dev, reg, *val);
	}

	return ret;
}

/**
 * regmap_read(): Read a value from a single register
 *
 * @map: Register map to write to
 * @reg: Register to be read from
 * @val: Pointer to store read value
 *
 * A value of zero will be returned on success, a negative errno will
 * be returned in error cases.
 */
int regmap_read(struct regmap *map, unsigned int reg, unsigned int *val)
{
	int ret;

	mutex_lock(&map->lock);

	ret = _regmap_read(map, reg, val);

	mutex_unlock(&map->lock);

	return ret;
}
EXPORT_SYMBOL_GPL(regmap_read);

/**
 * regmap_raw_read(): Read raw data from the device
 *
 * @map: Register map to write to
 * @reg: First register to be read from
 * @val: Pointer to store read value
 * @val_len: Size of data to read
 *
 * A value of zero will be returned on success, a negative errno will
 * be returned in error cases.
 */
int regmap_raw_read(struct regmap *map, unsigned int reg, void *val,
		    size_t val_len)
{
	size_t val_bytes = map->format.val_bytes;
	size_t val_count = val_len / val_bytes;
	unsigned int v;
	int ret, i;

	mutex_lock(&map->lock);

	if (regmap_volatile_range(map, reg, val_count) || map->cache_bypass ||
	    map->cache_type == REGCACHE_NONE) {
		/* Physical block read if there's no cache involved */
		ret = _regmap_raw_read(map, reg, val, val_len);

	} else {
		/* Otherwise go word by word for the cache; should be low
		 * cost as we expect to hit the cache.
		 */
		for (i = 0; i < val_count; i++) {
			ret = _regmap_read(map, reg + i, &v);
			if (ret != 0)
				goto out;

			map->format.format_val(val + (i * val_bytes), v);
		}
	}

 out:
	mutex_unlock(&map->lock);

	return ret;
}
EXPORT_SYMBOL_GPL(regmap_raw_read);

/**
 * regmap_bulk_read(): Read multiple registers from the device
 *
 * @map: Register map to write to
 * @reg: First register to be read from
 * @val: Pointer to store read value, in native register size for device
 * @val_count: Number of registers to read
 *
 * A value of zero will be returned on success, a negative errno will
 * be returned in error cases.
 */
int regmap_bulk_read(struct regmap *map, unsigned int reg, void *val,
		     size_t val_count)
{
	int ret, i;
	size_t val_bytes = map->format.val_bytes;
	bool vol = regmap_volatile_range(map, reg, val_count);

	if (!map->format.parse_val)
		return -EINVAL;

	if (vol || map->cache_type == REGCACHE_NONE) {
		ret = regmap_raw_read(map, reg, val, val_bytes * val_count);
		if (ret != 0)
			return ret;

		for (i = 0; i < val_count * val_bytes; i += val_bytes)
			map->format.parse_val(val + i);
	} else {
		for (i = 0; i < val_count; i++) {
			unsigned int ival;
			ret = regmap_read(map, reg + i, &ival);
			if (ret != 0)
				return ret;
			memcpy(val + (i * val_bytes), &ival, val_bytes);
		}
	}

	return 0;
}
EXPORT_SYMBOL_GPL(regmap_bulk_read);

static int _regmap_update_bits(struct regmap *map, unsigned int reg,
			       unsigned int mask, unsigned int val,
			       bool *change)
{
	int ret;
	unsigned int tmp, orig;

	mutex_lock(&map->lock);

	ret = _regmap_read(map, reg, &orig);
	if (ret != 0)
		goto out;

	tmp = orig & ~mask;
	tmp |= val & mask;

	if (tmp != orig) {
		ret = _regmap_write(map, reg, tmp);
		*change = true;
	} else {
		*change = false;
	}

out:
	mutex_unlock(&map->lock);

	return ret;
}

/**
 * regmap_update_bits: Perform a read/modify/write cycle on the register map
 *
 * @map: Register map to update
 * @reg: Register to update
 * @mask: Bitmask to change
 * @val: New value for bitmask
 *
 * Returns zero for success, a negative number on error.
 */
int regmap_update_bits(struct regmap *map, unsigned int reg,
		       unsigned int mask, unsigned int val)
{
	bool change;
	return _regmap_update_bits(map, reg, mask, val, &change);
}
EXPORT_SYMBOL_GPL(regmap_update_bits);

/**
 * regmap_update_bits_check: Perform a read/modify/write cycle on the
 *                           register map and report if updated
 *
 * @map: Register map to update
 * @reg: Register to update
 * @mask: Bitmask to change
 * @val: New value for bitmask
 * @change: Boolean indicating if a write was done
 *
 * Returns zero for success, a negative number on error.
 */
int regmap_update_bits_check(struct regmap *map, unsigned int reg,
			     unsigned int mask, unsigned int val,
			     bool *change)
{
	return _regmap_update_bits(map, reg, mask, val, change);
}
EXPORT_SYMBOL_GPL(regmap_update_bits_check);

/**
 * regmap_register_patch: Register and apply register updates to be applied
 *                        on device initialistion
 *
 * @map: Register map to apply updates to.
 * @regs: Values to update.
 * @num_regs: Number of entries in regs.
 *
 * Register a set of register updates to be applied to the device
 * whenever the device registers are synchronised with the cache and
 * apply them immediately.  Typically this is used to apply
 * corrections to be applied to the device defaults on startup, such
 * as the updates some vendors provide to undocumented registers.
 */
int regmap_register_patch(struct regmap *map, const struct reg_default *regs,
			  int num_regs)
{
	int i, ret;
	bool bypass;

	/* If needed the implementation can be extended to support this */
	if (map->patch)
		return -EBUSY;

	mutex_lock(&map->lock);

	bypass = map->cache_bypass;

	map->cache_bypass = true;

	/* Write out first; it's useful to apply even if we fail later. */
	for (i = 0; i < num_regs; i++) {
		ret = _regmap_write(map, regs[i].reg, regs[i].def);
		if (ret != 0) {
			dev_err(map->dev, "Failed to write %x = %x: %d\n",
				regs[i].reg, regs[i].def, ret);
			goto out;
		}
	}

	map->patch = kcalloc(num_regs, sizeof(struct reg_default), GFP_KERNEL);
	if (map->patch != NULL) {
		memcpy(map->patch, regs,
		       num_regs * sizeof(struct reg_default));
		map->patch_regs = num_regs;
	} else {
		ret = -ENOMEM;
	}

out:
	map->cache_bypass = bypass;

	mutex_unlock(&map->lock);

	return ret;
}
EXPORT_SYMBOL_GPL(regmap_register_patch);

/*
 * regmap_get_val_bytes(): Report the size of a register value
 *
 * Report the size of a register value, mainly intended to for use by
 * generic infrastructure built on top of regmap.
 */
int regmap_get_val_bytes(struct regmap *map)
{
	if (map->format.format_write)
		return -EINVAL;

	return map->format.val_bytes;
}
EXPORT_SYMBOL_GPL(regmap_get_val_bytes);

static int __init regmap_initcall(void)
{
	regmap_debugfs_initcall();

	return 0;
}
postcore_initcall(regmap_initcall);