summaryrefslogtreecommitdiff
path: root/drivers/regulator/max8997.c
blob: 2b97ec8f6a8363a02385caa01579b83ecc471966 (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
937
938
939
940
941
942
943
944
945
946
947
948
949
950
951
952
953
954
955
956
957
958
959
960
961
962
963
964
965
966
967
968
969
970
971
972
973
974
975
976
977
978
979
980
981
982
983
984
985
986
987
988
989
990
991
992
993
994
995
996
997
998
999
1000
1001
1002
1003
1004
1005
1006
1007
1008
1009
1010
1011
1012
1013
1014
1015
1016
1017
1018
1019
1020
1021
1022
1023
1024
1025
1026
1027
1028
1029
1030
1031
1032
1033
1034
1035
1036
1037
1038
1039
1040
1041
1042
1043
1044
1045
1046
1047
1048
1049
1050
1051
1052
1053
1054
1055
1056
1057
1058
1059
1060
1061
1062
1063
1064
1065
1066
1067
1068
1069
1070
1071
1072
1073
1074
1075
1076
1077
1078
1079
1080
1081
1082
1083
1084
1085
1086
1087
1088
1089
1090
1091
1092
1093
1094
1095
1096
1097
1098
1099
1100
1101
1102
1103
1104
1105
1106
1107
1108
1109
1110
1111
1112
1113
1114
1115
1116
1117
1118
1119
1120
1121
1122
1123
1124
1125
1126
1127
1128
1129
1130
1131
1132
1133
1134
1135
1136
1137
1138
1139
1140
1141
1142
1143
1144
1145
1146
1147
1148
1149
1150
1151
1152
1153
1154
1155
1156
1157
1158
1159
1160
1161
1162
1163
1164
/*
 * max8997.c - Regulator driver for the Maxim 8997/8966
 *
 * Copyright (C) 2011 Samsung Electronics
 * MyungJoo Ham <myungjoo.ham@smasung.com>
 *
 * This program is free software; you can redistribute it and/or modify
 * it under the terms of the GNU General Public License as published by
 * the Free Software Foundation; either version 2 of the License, or
 * (at your option) any later version.
 *
 * This program is distributed in the hope that it will be useful,
 * but WITHOUT ANY WARRANTY; without even the implied warranty of
 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
 * GNU General Public License for more details.
 *
 * You should have received a copy of the GNU General Public License
 * along with this program; if not, write to the Free Software
 * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA  02111-1307  USA
 *
 * This driver is based on max8998.c
 */

#include <linux/bug.h>
#include <linux/err.h>
#include <linux/gpio.h>
#include <linux/slab.h>
#include <linux/module.h>
#include <linux/platform_device.h>
#include <linux/regulator/driver.h>
#include <linux/regulator/machine.h>
#include <linux/mfd/max8997.h>
#include <linux/mfd/max8997-private.h>

struct max8997_data {
	struct device *dev;
	struct max8997_dev *iodev;
	int num_regulators;
	struct regulator_dev **rdev;
	int ramp_delay; /* in mV/us */

	bool buck1_gpiodvs;
	bool buck2_gpiodvs;
	bool buck5_gpiodvs;
	u8 buck1_vol[8];
	u8 buck2_vol[8];
	u8 buck5_vol[8];
	int buck125_gpios[3];
	int buck125_gpioindex;
	bool ignore_gpiodvs_side_effect;

	u8 saved_states[MAX8997_REG_MAX];
};

static inline void max8997_set_gpio(struct max8997_data *max8997)
{
	int set3 = (max8997->buck125_gpioindex) & 0x1;
	int set2 = ((max8997->buck125_gpioindex) >> 1) & 0x1;
	int set1 = ((max8997->buck125_gpioindex) >> 2) & 0x1;

	gpio_set_value(max8997->buck125_gpios[0], set1);
	gpio_set_value(max8997->buck125_gpios[1], set2);
	gpio_set_value(max8997->buck125_gpios[2], set3);
}

struct voltage_map_desc {
	int min;
	int max;
	int step;
};

/* Voltage maps in mV */
static const struct voltage_map_desc ldo_voltage_map_desc = {
	.min = 800,	.max = 3950,	.step = 50,
}; /* LDO1 ~ 18, 21 all */

static const struct voltage_map_desc buck1245_voltage_map_desc = {
	.min = 650,	.max = 2225,	.step = 25,
}; /* Buck1, 2, 4, 5 */

static const struct voltage_map_desc buck37_voltage_map_desc = {
	.min = 750,	.max = 3900,	.step = 50,
}; /* Buck3, 7 */

/* current map in mA */
static const struct voltage_map_desc charger_current_map_desc = {
	.min = 200,	.max = 950,	.step = 50,
};

static const struct voltage_map_desc topoff_current_map_desc = {
	.min = 50,	.max = 200,	.step = 10,
};

static const struct voltage_map_desc *reg_voltage_map[] = {
	[MAX8997_LDO1] = &ldo_voltage_map_desc,
	[MAX8997_LDO2] = &ldo_voltage_map_desc,
	[MAX8997_LDO3] = &ldo_voltage_map_desc,
	[MAX8997_LDO4] = &ldo_voltage_map_desc,
	[MAX8997_LDO5] = &ldo_voltage_map_desc,
	[MAX8997_LDO6] = &ldo_voltage_map_desc,
	[MAX8997_LDO7] = &ldo_voltage_map_desc,
	[MAX8997_LDO8] = &ldo_voltage_map_desc,
	[MAX8997_LDO9] = &ldo_voltage_map_desc,
	[MAX8997_LDO10] = &ldo_voltage_map_desc,
	[MAX8997_LDO11] = &ldo_voltage_map_desc,
	[MAX8997_LDO12] = &ldo_voltage_map_desc,
	[MAX8997_LDO13] = &ldo_voltage_map_desc,
	[MAX8997_LDO14] = &ldo_voltage_map_desc,
	[MAX8997_LDO15] = &ldo_voltage_map_desc,
	[MAX8997_LDO16] = &ldo_voltage_map_desc,
	[MAX8997_LDO17] = &ldo_voltage_map_desc,
	[MAX8997_LDO18] = &ldo_voltage_map_desc,
	[MAX8997_LDO21] = &ldo_voltage_map_desc,
	[MAX8997_BUCK1] = &buck1245_voltage_map_desc,
	[MAX8997_BUCK2] = &buck1245_voltage_map_desc,
	[MAX8997_BUCK3] = &buck37_voltage_map_desc,
	[MAX8997_BUCK4] = &buck1245_voltage_map_desc,
	[MAX8997_BUCK5] = &buck1245_voltage_map_desc,
	[MAX8997_BUCK6] = NULL,
	[MAX8997_BUCK7] = &buck37_voltage_map_desc,
	[MAX8997_EN32KHZ_AP] = NULL,
	[MAX8997_EN32KHZ_CP] = NULL,
	[MAX8997_ENVICHG] = NULL,
	[MAX8997_ESAFEOUT1] = NULL,
	[MAX8997_ESAFEOUT2] = NULL,
	[MAX8997_CHARGER_CV] = NULL,
	[MAX8997_CHARGER] = &charger_current_map_desc,
	[MAX8997_CHARGER_TOPOFF] = &topoff_current_map_desc,
};

static int max8997_list_voltage_safeout(struct regulator_dev *rdev,
		unsigned int selector)
{
	int rid = rdev_get_id(rdev);

	if (rid == MAX8997_ESAFEOUT1 || rid == MAX8997_ESAFEOUT2) {
		switch (selector) {
		case 0:
			return 4850000;
		case 1:
			return 4900000;
		case 2:
			return 4950000;
		case 3:
			return 3300000;
		default:
			return -EINVAL;
		}
	}

	return -EINVAL;
}

static int max8997_list_voltage_charger_cv(struct regulator_dev *rdev,
		unsigned int selector)
{
	int rid = rdev_get_id(rdev);

	if (rid != MAX8997_CHARGER_CV)
		goto err;

	switch (selector) {
	case 0x00:
		return 4200000;
	case 0x01 ... 0x0E:
		return 4000000 + 20000 * (selector - 0x01);
	case 0x0F:
		return 4350000;
	default:
		return -EINVAL;
	}
err:
	return -EINVAL;
}

static int max8997_list_voltage(struct regulator_dev *rdev,
		unsigned int selector)
{
	const struct voltage_map_desc *desc;
	int rid = rdev_get_id(rdev);
	int val;

	if (rid >= ARRAY_SIZE(reg_voltage_map) ||
			rid < 0)
		return -EINVAL;

	desc = reg_voltage_map[rid];
	if (desc == NULL)
		return -EINVAL;

	val = desc->min + desc->step * selector;
	if (val > desc->max)
		return -EINVAL;

	return val * 1000;
}

static int max8997_get_enable_register(struct regulator_dev *rdev,
		int *reg, int *mask, int *pattern)
{
	int rid = rdev_get_id(rdev);

	switch (rid) {
	case MAX8997_LDO1 ... MAX8997_LDO21:
		*reg = MAX8997_REG_LDO1CTRL + (rid - MAX8997_LDO1);
		*mask = 0xC0;
		*pattern = 0xC0;
		break;
	case MAX8997_BUCK1:
		*reg = MAX8997_REG_BUCK1CTRL;
		*mask = 0x01;
		*pattern = 0x01;
		break;
	case MAX8997_BUCK2:
		*reg = MAX8997_REG_BUCK2CTRL;
		*mask = 0x01;
		*pattern = 0x01;
		break;
	case MAX8997_BUCK3:
		*reg = MAX8997_REG_BUCK3CTRL;
		*mask = 0x01;
		*pattern = 0x01;
		break;
	case MAX8997_BUCK4:
		*reg = MAX8997_REG_BUCK4CTRL;
		*mask = 0x01;
		*pattern = 0x01;
		break;
	case MAX8997_BUCK5:
		*reg = MAX8997_REG_BUCK5CTRL;
		*mask = 0x01;
		*pattern = 0x01;
		break;
	case MAX8997_BUCK6:
		*reg = MAX8997_REG_BUCK6CTRL;
		*mask = 0x01;
		*pattern = 0x01;
		break;
	case MAX8997_BUCK7:
		*reg = MAX8997_REG_BUCK7CTRL;
		*mask = 0x01;
		*pattern = 0x01;
		break;
	case MAX8997_EN32KHZ_AP ... MAX8997_EN32KHZ_CP:
		*reg = MAX8997_REG_MAINCON1;
		*mask = 0x01 << (rid - MAX8997_EN32KHZ_AP);
		*pattern = 0x01 << (rid - MAX8997_EN32KHZ_AP);
		break;
	case MAX8997_ENVICHG:
		*reg = MAX8997_REG_MBCCTRL1;
		*mask = 0x80;
		*pattern = 0x80;
		break;
	case MAX8997_ESAFEOUT1 ... MAX8997_ESAFEOUT2:
		*reg = MAX8997_REG_SAFEOUTCTRL;
		*mask = 0x40 << (rid - MAX8997_ESAFEOUT1);
		*pattern = 0x40 << (rid - MAX8997_ESAFEOUT1);
		break;
	case MAX8997_CHARGER:
		*reg = MAX8997_REG_MBCCTRL2;
		*mask = 0x40;
		*pattern = 0x40;
		break;
	default:
		/* Not controllable or not exists */
		return -EINVAL;
	}

	return 0;
}

static int max8997_reg_is_enabled(struct regulator_dev *rdev)
{
	struct max8997_data *max8997 = rdev_get_drvdata(rdev);
	struct i2c_client *i2c = max8997->iodev->i2c;
	int ret, reg, mask, pattern;
	u8 val;

	ret = max8997_get_enable_register(rdev, &reg, &mask, &pattern);
	if (ret)
		return ret;

	ret = max8997_read_reg(i2c, reg, &val);
	if (ret)
		return ret;

	return (val & mask) == pattern;
}

static int max8997_reg_enable(struct regulator_dev *rdev)
{
	struct max8997_data *max8997 = rdev_get_drvdata(rdev);
	struct i2c_client *i2c = max8997->iodev->i2c;
	int ret, reg, mask, pattern;

	ret = max8997_get_enable_register(rdev, &reg, &mask, &pattern);
	if (ret)
		return ret;

	return max8997_update_reg(i2c, reg, pattern, mask);
}

static int max8997_reg_disable(struct regulator_dev *rdev)
{
	struct max8997_data *max8997 = rdev_get_drvdata(rdev);
	struct i2c_client *i2c = max8997->iodev->i2c;
	int ret, reg, mask, pattern;

	ret = max8997_get_enable_register(rdev, &reg, &mask, &pattern);
	if (ret)
		return ret;

	return max8997_update_reg(i2c, reg, ~pattern, mask);
}

static int max8997_get_voltage_register(struct regulator_dev *rdev,
		int *_reg, int *_shift, int *_mask)
{
	struct max8997_data *max8997 = rdev_get_drvdata(rdev);
	int rid = rdev_get_id(rdev);
	int reg, shift = 0, mask = 0x3f;

	switch (rid) {
	case MAX8997_LDO1 ... MAX8997_LDO21:
		reg = MAX8997_REG_LDO1CTRL + (rid - MAX8997_LDO1);
		break;
	case MAX8997_BUCK1:
		reg = MAX8997_REG_BUCK1DVS1;
		if (max8997->buck1_gpiodvs)
			reg += max8997->buck125_gpioindex;
		break;
	case MAX8997_BUCK2:
		reg = MAX8997_REG_BUCK2DVS1;
		if (max8997->buck2_gpiodvs)
			reg += max8997->buck125_gpioindex;
		break;
	case MAX8997_BUCK3:
		reg = MAX8997_REG_BUCK3DVS;
		break;
	case MAX8997_BUCK4:
		reg = MAX8997_REG_BUCK4DVS;
		break;
	case MAX8997_BUCK5:
		reg = MAX8997_REG_BUCK5DVS1;
		if (max8997->buck5_gpiodvs)
			reg += max8997->buck125_gpioindex;
		break;
	case MAX8997_BUCK7:
		reg = MAX8997_REG_BUCK7DVS;
		break;
	case MAX8997_ESAFEOUT1 ...  MAX8997_ESAFEOUT2:
		reg = MAX8997_REG_SAFEOUTCTRL;
		shift = (rid == MAX8997_ESAFEOUT2) ? 2 : 0;
		mask = 0x3;
		break;
	case MAX8997_CHARGER_CV:
		reg = MAX8997_REG_MBCCTRL3;
		shift = 0;
		mask = 0xf;
		break;
	case MAX8997_CHARGER:
		reg = MAX8997_REG_MBCCTRL4;
		shift = 0;
		mask = 0xf;
		break;
	case MAX8997_CHARGER_TOPOFF:
		reg = MAX8997_REG_MBCCTRL5;
		shift = 0;
		mask = 0xf;
		break;
	default:
		return -EINVAL;
	}

	*_reg = reg;
	*_shift = shift;
	*_mask = mask;

	return 0;
}

static int max8997_get_voltage_sel(struct regulator_dev *rdev)
{
	struct max8997_data *max8997 = rdev_get_drvdata(rdev);
	struct i2c_client *i2c = max8997->iodev->i2c;
	int reg, shift, mask, ret;
	u8 val;

	ret = max8997_get_voltage_register(rdev, &reg, &shift, &mask);
	if (ret)
		return ret;

	ret = max8997_read_reg(i2c, reg, &val);
	if (ret)
		return ret;

	val >>= shift;
	val &= mask;

	return val;
}

static inline int max8997_get_voltage_proper_val(
		const struct voltage_map_desc *desc,
		int min_vol, int max_vol)
{
	int i;

	if (desc == NULL)
		return -EINVAL;

	if (max_vol < desc->min || min_vol > desc->max)
		return -EINVAL;

	if (min_vol < desc->min)
		min_vol = desc->min;

	i = DIV_ROUND_UP(min_vol - desc->min, desc->step);

	if (desc->min + desc->step * i > max_vol)
		return -EINVAL;

	return i;
}

static int max8997_set_voltage_charger_cv(struct regulator_dev *rdev,
		int min_uV, int max_uV, unsigned *selector)
{
	struct max8997_data *max8997 = rdev_get_drvdata(rdev);
	struct i2c_client *i2c = max8997->iodev->i2c;
	int rid = rdev_get_id(rdev);
	int lb, ub;
	int reg, shift = 0, mask, ret = 0;
	u8 val = 0x0;

	if (rid != MAX8997_CHARGER_CV)
		return -EINVAL;

	ret = max8997_get_voltage_register(rdev, &reg, &shift, &mask);
	if (ret)
		return ret;

	if (max_uV < 4000000 || min_uV > 4350000)
		return -EINVAL;

	if (min_uV <= 4000000) {
		if (max_uV >= 4000000)
			return -EINVAL;
		else
			val = 0x1;
	} else if (min_uV <= 4200000 && max_uV >= 4200000)
		val = 0x0;
	else {
		lb = (min_uV - 4000001) / 20000 + 2;
		ub = (max_uV - 4000000) / 20000 + 1;

		if (lb > ub)
			return -EINVAL;

		if (lb < 0xf)
			val = lb;
		else {
			if (ub >= 0xf)
				val = 0xf;
			else
				return -EINVAL;
		}
	}

	*selector = val;

	ret = max8997_update_reg(i2c, reg, val << shift, mask);

	return ret;
}

/*
 * For LDO1 ~ LDO21, BUCK1~5, BUCK7, CHARGER, CHARGER_TOPOFF
 * BUCK1, 2, and 5 are available if they are not controlled by gpio
 */
static int max8997_set_voltage_ldobuck(struct regulator_dev *rdev,
		int min_uV, int max_uV, unsigned *selector)
{
	struct max8997_data *max8997 = rdev_get_drvdata(rdev);
	struct i2c_client *i2c = max8997->iodev->i2c;
	int min_vol = min_uV / 1000, max_vol = max_uV / 1000;
	const struct voltage_map_desc *desc;
	int rid = rdev_get_id(rdev);
	int i, reg, shift, mask, ret;

	switch (rid) {
	case MAX8997_LDO1 ... MAX8997_LDO21:
		break;
	case MAX8997_BUCK1 ... MAX8997_BUCK5:
		break;
	case MAX8997_BUCK6:
		return -EINVAL;
	case MAX8997_BUCK7:
		break;
	case MAX8997_CHARGER:
		break;
	case MAX8997_CHARGER_TOPOFF:
		break;
	default:
		return -EINVAL;
	}

	desc = reg_voltage_map[rid];

	i = max8997_get_voltage_proper_val(desc, min_vol, max_vol);
	if (i < 0)
		return i;

	ret = max8997_get_voltage_register(rdev, &reg, &shift, &mask);
	if (ret)
		return ret;

	ret = max8997_update_reg(i2c, reg, i << shift, mask << shift);
	*selector = i;

	return ret;
}

static int max8997_set_voltage_ldobuck_time_sel(struct regulator_dev *rdev,
						unsigned int old_selector,
						unsigned int new_selector)
{
	struct max8997_data *max8997 = rdev_get_drvdata(rdev);
	int rid = rdev_get_id(rdev);
	const struct voltage_map_desc *desc = reg_voltage_map[rid];

	/* Delay is required only if the voltage is increasing */
	if (old_selector >= new_selector)
		return 0;

	/* No need to delay if gpio_dvs_mode */
	switch (rid) {
	case MAX8997_BUCK1:
		if (max8997->buck1_gpiodvs)
			return 0;
		break;
	case MAX8997_BUCK2:
		if (max8997->buck2_gpiodvs)
			return 0;
		break;
	case MAX8997_BUCK5:
		if (max8997->buck5_gpiodvs)
			return 0;
		break;
	}

	switch (rid) {
	case MAX8997_BUCK1:
	case MAX8997_BUCK2:
	case MAX8997_BUCK4:
	case MAX8997_BUCK5:
		return DIV_ROUND_UP(desc->step * (new_selector - old_selector),
				    max8997->ramp_delay);
	}

	return 0;
}

/*
 * Assess the damage on the voltage setting of BUCK1,2,5 by the change.
 *
 * When GPIO-DVS mode is used for multiple bucks, changing the voltage value
 * of one of the bucks may affect that of another buck, which is the side
 * effect of the change (set_voltage). This function examines the GPIO-DVS
 * configurations and checks whether such side-effect exists.
 */
static int max8997_assess_side_effect(struct regulator_dev *rdev,
		u8 new_val, int *best)
{
	struct max8997_data *max8997 = rdev_get_drvdata(rdev);
	int rid = rdev_get_id(rdev);
	u8 *buckx_val[3];
	bool buckx_gpiodvs[3];
	int side_effect[8];
	int min_side_effect = INT_MAX;
	int i;

	*best = -1;

	switch (rid) {
	case MAX8997_BUCK1:
		rid = 0;
		break;
	case MAX8997_BUCK2:
		rid = 1;
		break;
	case MAX8997_BUCK5:
		rid = 2;
		break;
	default:
		return -EINVAL;
	}

	buckx_val[0] = max8997->buck1_vol;
	buckx_val[1] = max8997->buck2_vol;
	buckx_val[2] = max8997->buck5_vol;
	buckx_gpiodvs[0] = max8997->buck1_gpiodvs;
	buckx_gpiodvs[1] = max8997->buck2_gpiodvs;
	buckx_gpiodvs[2] = max8997->buck5_gpiodvs;

	for (i = 0; i < 8; i++) {
		int others;

		if (new_val != (buckx_val[rid])[i]) {
			side_effect[i] = -1;
			continue;
		}

		side_effect[i] = 0;
		for (others = 0; others < 3; others++) {
			int diff;

			if (others == rid)
				continue;
			if (buckx_gpiodvs[others] == false)
				continue; /* Not affected */
			diff = (buckx_val[others])[i] -
				(buckx_val[others])[max8997->buck125_gpioindex];
			if (diff > 0)
				side_effect[i] += diff;
			else if (diff < 0)
				side_effect[i] -= diff;
		}
		if (side_effect[i] == 0) {
			*best = i;
			return 0; /* NO SIDE EFFECT! Use This! */
		}
		if (side_effect[i] < min_side_effect) {
			min_side_effect = side_effect[i];
			*best = i;
		}
	}

	if (*best == -1)
		return -EINVAL;

	return side_effect[*best];
}

/*
 * For Buck 1 ~ 5 and 7. If it is not controlled by GPIO, this calls
 * max8997_set_voltage_ldobuck to do the job.
 */
static int max8997_set_voltage_buck(struct regulator_dev *rdev,
		int min_uV, int max_uV, unsigned *selector)
{
	struct max8997_data *max8997 = rdev_get_drvdata(rdev);
	int rid = rdev_get_id(rdev);
	const struct voltage_map_desc *desc;
	int new_val, new_idx, damage, tmp_val, tmp_idx, tmp_dmg;
	bool gpio_dvs_mode = false;
	int min_vol = min_uV / 1000, max_vol = max_uV / 1000;

	if (rid < MAX8997_BUCK1 || rid > MAX8997_BUCK7)
		return -EINVAL;

	switch (rid) {
	case MAX8997_BUCK1:
		if (max8997->buck1_gpiodvs)
			gpio_dvs_mode = true;
		break;
	case MAX8997_BUCK2:
		if (max8997->buck2_gpiodvs)
			gpio_dvs_mode = true;
		break;
	case MAX8997_BUCK5:
		if (max8997->buck5_gpiodvs)
			gpio_dvs_mode = true;
		break;
	}

	if (!gpio_dvs_mode)
		return max8997_set_voltage_ldobuck(rdev, min_uV, max_uV,
						selector);

	desc = reg_voltage_map[rid];
	new_val = max8997_get_voltage_proper_val(desc, min_vol, max_vol);
	if (new_val < 0)
		return new_val;

	tmp_dmg = INT_MAX;
	tmp_idx = -1;
	tmp_val = -1;
	do {
		damage = max8997_assess_side_effect(rdev, new_val, &new_idx);
		if (damage == 0)
			goto out;

		if (tmp_dmg > damage) {
			tmp_idx = new_idx;
			tmp_val = new_val;
			tmp_dmg = damage;
		}

		new_val++;
	} while (desc->min + desc->step * new_val <= desc->max);

	new_idx = tmp_idx;
	new_val = tmp_val;

	if (max8997->ignore_gpiodvs_side_effect == false)
		return -EINVAL;

	dev_warn(&rdev->dev, "MAX8997 GPIO-DVS Side Effect Warning: GPIO SET:"
			" %d -> %d\n", max8997->buck125_gpioindex, tmp_idx);

out:
	if (new_idx < 0 || new_val < 0)
		return -EINVAL;

	max8997->buck125_gpioindex = new_idx;
	max8997_set_gpio(max8997);
	*selector = new_val;

	return 0;
}

static const int safeoutvolt[] = {
	3300000,
	4850000,
	4900000,
	4950000,
};

/* For SAFEOUT1 and SAFEOUT2 */
static int max8997_set_voltage_safeout(struct regulator_dev *rdev,
		int min_uV, int max_uV, unsigned *selector)
{
	struct max8997_data *max8997 = rdev_get_drvdata(rdev);
	struct i2c_client *i2c = max8997->iodev->i2c;
	int rid = rdev_get_id(rdev);
	int reg, shift = 0, mask, ret;
	int i = 0;
	u8 val;

	if (rid != MAX8997_ESAFEOUT1 && rid != MAX8997_ESAFEOUT2)
		return -EINVAL;

	for (i = 0; i < ARRAY_SIZE(safeoutvolt); i++) {
		if (min_uV <= safeoutvolt[i] &&
				max_uV >= safeoutvolt[i])
			break;
	}

	if (i >= ARRAY_SIZE(safeoutvolt))
		return -EINVAL;

	if (i == 0)
		val = 0x3;
	else
		val = i - 1;

	ret = max8997_get_voltage_register(rdev, &reg, &shift, &mask);
	if (ret)
		return ret;

	ret = max8997_update_reg(i2c, reg, val << shift, mask << shift);
	*selector = val;

	return ret;
}

static int max8997_reg_disable_suspend(struct regulator_dev *rdev)
{
	struct max8997_data *max8997 = rdev_get_drvdata(rdev);
	struct i2c_client *i2c = max8997->iodev->i2c;
	int ret, reg, mask, pattern;
	int rid = rdev_get_id(rdev);

	ret = max8997_get_enable_register(rdev, &reg, &mask, &pattern);
	if (ret)
		return ret;

	max8997_read_reg(i2c, reg, &max8997->saved_states[rid]);

	if (rid == MAX8997_LDO1 ||
			rid == MAX8997_LDO10 ||
			rid == MAX8997_LDO21) {
		dev_dbg(&rdev->dev, "Conditional Power-Off for %s\n",
				rdev->desc->name);
		return max8997_update_reg(i2c, reg, 0x40, mask);
	}

	dev_dbg(&rdev->dev, "Full Power-Off for %s (%xh -> %xh)\n",
			rdev->desc->name, max8997->saved_states[rid] & mask,
			(~pattern) & mask);
	return max8997_update_reg(i2c, reg, ~pattern, mask);
}

static struct regulator_ops max8997_ldo_ops = {
	.list_voltage		= max8997_list_voltage,
	.is_enabled		= max8997_reg_is_enabled,
	.enable			= max8997_reg_enable,
	.disable		= max8997_reg_disable,
	.get_voltage_sel	= max8997_get_voltage_sel,
	.set_voltage		= max8997_set_voltage_ldobuck,
	.set_voltage_time_sel	= max8997_set_voltage_ldobuck_time_sel,
	.set_suspend_disable	= max8997_reg_disable_suspend,
};

static struct regulator_ops max8997_buck_ops = {
	.list_voltage		= max8997_list_voltage,
	.is_enabled		= max8997_reg_is_enabled,
	.enable			= max8997_reg_enable,
	.disable		= max8997_reg_disable,
	.get_voltage_sel	= max8997_get_voltage_sel,
	.set_voltage		= max8997_set_voltage_buck,
	.set_voltage_time_sel	= max8997_set_voltage_ldobuck_time_sel,
	.set_suspend_disable	= max8997_reg_disable_suspend,
};

static struct regulator_ops max8997_fixedvolt_ops = {
	.list_voltage		= max8997_list_voltage,
	.is_enabled		= max8997_reg_is_enabled,
	.enable			= max8997_reg_enable,
	.disable		= max8997_reg_disable,
	.set_suspend_disable	= max8997_reg_disable_suspend,
};

static struct regulator_ops max8997_safeout_ops = {
	.list_voltage		= max8997_list_voltage_safeout,
	.is_enabled		= max8997_reg_is_enabled,
	.enable			= max8997_reg_enable,
	.disable		= max8997_reg_disable,
	.get_voltage_sel	= max8997_get_voltage_sel,
	.set_voltage		= max8997_set_voltage_safeout,
	.set_suspend_disable	= max8997_reg_disable_suspend,
};

static struct regulator_ops max8997_fixedstate_ops = {
	.list_voltage		= max8997_list_voltage_charger_cv,
	.get_voltage_sel	= max8997_get_voltage_sel,
	.set_voltage		= max8997_set_voltage_charger_cv,
};

static int max8997_set_current_limit(struct regulator_dev *rdev,
				     int min_uA, int max_uA)
{
	unsigned dummy;
	int rid = rdev_get_id(rdev);

	if (rid != MAX8997_CHARGER && rid != MAX8997_CHARGER_TOPOFF)
		return -EINVAL;

	/* Reuse max8997_set_voltage_ldobuck to set current_limit. */
	return max8997_set_voltage_ldobuck(rdev, min_uA, max_uA, &dummy);
}

static int max8997_get_current_limit(struct regulator_dev *rdev)
{
	int sel, rid = rdev_get_id(rdev);

	if (rid != MAX8997_CHARGER && rid != MAX8997_CHARGER_TOPOFF)
		return -EINVAL;

	sel = max8997_get_voltage_sel(rdev);
	if (sel < 0)
		return sel;

	/* Reuse max8997_list_voltage to get current_limit. */
	return max8997_list_voltage(rdev, sel);
}

static struct regulator_ops max8997_charger_ops = {
	.is_enabled		= max8997_reg_is_enabled,
	.enable			= max8997_reg_enable,
	.disable		= max8997_reg_disable,
	.get_current_limit	= max8997_get_current_limit,
	.set_current_limit	= max8997_set_current_limit,
};

static struct regulator_ops max8997_charger_fixedstate_ops = {
	.get_current_limit	= max8997_get_current_limit,
	.set_current_limit	= max8997_set_current_limit,
};

#define MAX8997_VOLTAGE_REGULATOR(_name, _ops) {\
	.name		= #_name,		\
	.id		= MAX8997_##_name,	\
	.ops		= &_ops,		\
	.type		= REGULATOR_VOLTAGE,	\
	.owner		= THIS_MODULE,		\
}

#define MAX8997_CURRENT_REGULATOR(_name, _ops) {\
	.name		= #_name,		\
	.id		= MAX8997_##_name,	\
	.ops		= &_ops,		\
	.type		= REGULATOR_CURRENT,	\
	.owner		= THIS_MODULE,		\
}

static struct regulator_desc regulators[] = {
	MAX8997_VOLTAGE_REGULATOR(LDO1, max8997_ldo_ops),
	MAX8997_VOLTAGE_REGULATOR(LDO2, max8997_ldo_ops),
	MAX8997_VOLTAGE_REGULATOR(LDO3, max8997_ldo_ops),
	MAX8997_VOLTAGE_REGULATOR(LDO4, max8997_ldo_ops),
	MAX8997_VOLTAGE_REGULATOR(LDO5, max8997_ldo_ops),
	MAX8997_VOLTAGE_REGULATOR(LDO6, max8997_ldo_ops),
	MAX8997_VOLTAGE_REGULATOR(LDO7, max8997_ldo_ops),
	MAX8997_VOLTAGE_REGULATOR(LDO8, max8997_ldo_ops),
	MAX8997_VOLTAGE_REGULATOR(LDO9, max8997_ldo_ops),
	MAX8997_VOLTAGE_REGULATOR(LDO10, max8997_ldo_ops),
	MAX8997_VOLTAGE_REGULATOR(LDO11, max8997_ldo_ops),
	MAX8997_VOLTAGE_REGULATOR(LDO12, max8997_ldo_ops),
	MAX8997_VOLTAGE_REGULATOR(LDO13, max8997_ldo_ops),
	MAX8997_VOLTAGE_REGULATOR(LDO14, max8997_ldo_ops),
	MAX8997_VOLTAGE_REGULATOR(LDO15, max8997_ldo_ops),
	MAX8997_VOLTAGE_REGULATOR(LDO16, max8997_ldo_ops),
	MAX8997_VOLTAGE_REGULATOR(LDO17, max8997_ldo_ops),
	MAX8997_VOLTAGE_REGULATOR(LDO18, max8997_ldo_ops),
	MAX8997_VOLTAGE_REGULATOR(LDO21, max8997_ldo_ops),
	MAX8997_VOLTAGE_REGULATOR(BUCK1, max8997_buck_ops),
	MAX8997_VOLTAGE_REGULATOR(BUCK2, max8997_buck_ops),
	MAX8997_VOLTAGE_REGULATOR(BUCK3, max8997_buck_ops),
	MAX8997_VOLTAGE_REGULATOR(BUCK4, max8997_buck_ops),
	MAX8997_VOLTAGE_REGULATOR(BUCK5, max8997_buck_ops),
	MAX8997_VOLTAGE_REGULATOR(BUCK6, max8997_fixedvolt_ops),
	MAX8997_VOLTAGE_REGULATOR(BUCK7, max8997_buck_ops),
	MAX8997_VOLTAGE_REGULATOR(EN32KHZ_AP, max8997_fixedvolt_ops),
	MAX8997_VOLTAGE_REGULATOR(EN32KHZ_CP, max8997_fixedvolt_ops),
	MAX8997_VOLTAGE_REGULATOR(ENVICHG, max8997_fixedvolt_ops),
	MAX8997_VOLTAGE_REGULATOR(ESAFEOUT1, max8997_safeout_ops),
	MAX8997_VOLTAGE_REGULATOR(ESAFEOUT2, max8997_safeout_ops),
	MAX8997_VOLTAGE_REGULATOR(CHARGER_CV, max8997_fixedstate_ops),
	MAX8997_CURRENT_REGULATOR(CHARGER, max8997_charger_ops),
	MAX8997_CURRENT_REGULATOR(CHARGER_TOPOFF,
				  max8997_charger_fixedstate_ops),
};

static __devinit int max8997_pmic_probe(struct platform_device *pdev)
{
	struct max8997_dev *iodev = dev_get_drvdata(pdev->dev.parent);
	struct max8997_platform_data *pdata = dev_get_platdata(iodev->dev);
	struct regulator_config config = { };
	struct regulator_dev **rdev;
	struct max8997_data *max8997;
	struct i2c_client *i2c;
	int i, ret, size;
	u8 max_buck1 = 0, max_buck2 = 0, max_buck5 = 0;

	if (!pdata) {
		dev_err(pdev->dev.parent, "No platform init data supplied.\n");
		return -ENODEV;
	}

	max8997 = devm_kzalloc(&pdev->dev, sizeof(struct max8997_data),
			       GFP_KERNEL);
	if (!max8997)
		return -ENOMEM;

	size = sizeof(struct regulator_dev *) * pdata->num_regulators;
	max8997->rdev = devm_kzalloc(&pdev->dev, size, GFP_KERNEL);
	if (!max8997->rdev)
		return -ENOMEM;

	rdev = max8997->rdev;
	max8997->dev = &pdev->dev;
	max8997->iodev = iodev;
	max8997->num_regulators = pdata->num_regulators;
	platform_set_drvdata(pdev, max8997);
	i2c = max8997->iodev->i2c;

	max8997->buck125_gpioindex = pdata->buck125_default_idx;
	max8997->buck1_gpiodvs = pdata->buck1_gpiodvs;
	max8997->buck2_gpiodvs = pdata->buck2_gpiodvs;
	max8997->buck5_gpiodvs = pdata->buck5_gpiodvs;
	memcpy(max8997->buck125_gpios, pdata->buck125_gpios, sizeof(int) * 3);
	max8997->ignore_gpiodvs_side_effect = pdata->ignore_gpiodvs_side_effect;

	for (i = 0; i < 8; i++) {
		max8997->buck1_vol[i] = ret =
			max8997_get_voltage_proper_val(
					&buck1245_voltage_map_desc,
					pdata->buck1_voltage[i] / 1000,
					pdata->buck1_voltage[i] / 1000 +
					buck1245_voltage_map_desc.step);
		if (ret < 0)
			goto err_out;

		max8997->buck2_vol[i] = ret =
			max8997_get_voltage_proper_val(
					&buck1245_voltage_map_desc,
					pdata->buck2_voltage[i] / 1000,
					pdata->buck2_voltage[i] / 1000 +
					buck1245_voltage_map_desc.step);
		if (ret < 0)
			goto err_out;

		max8997->buck5_vol[i] = ret =
			max8997_get_voltage_proper_val(
					&buck1245_voltage_map_desc,
					pdata->buck5_voltage[i] / 1000,
					pdata->buck5_voltage[i] / 1000 +
					buck1245_voltage_map_desc.step);
		if (ret < 0)
			goto err_out;

		if (max_buck1 < max8997->buck1_vol[i])
			max_buck1 = max8997->buck1_vol[i];
		if (max_buck2 < max8997->buck2_vol[i])
			max_buck2 = max8997->buck2_vol[i];
		if (max_buck5 < max8997->buck5_vol[i])
			max_buck5 = max8997->buck5_vol[i];
	}

	/* For the safety, set max voltage before setting up */
	for (i = 0; i < 8; i++) {
		max8997_update_reg(i2c, MAX8997_REG_BUCK1DVS1 + i,
				max_buck1, 0x3f);
		max8997_update_reg(i2c, MAX8997_REG_BUCK2DVS1 + i,
				max_buck2, 0x3f);
		max8997_update_reg(i2c, MAX8997_REG_BUCK5DVS1 + i,
				max_buck5, 0x3f);
	}

	/*
	 * If buck 1, 2, and 5 do not care DVS GPIO settings, ignore them.
	 * If at least one of them cares, set gpios.
	 */
	if (pdata->buck1_gpiodvs || pdata->buck2_gpiodvs ||
			pdata->buck5_gpiodvs) {

		if (!gpio_is_valid(pdata->buck125_gpios[0]) ||
				!gpio_is_valid(pdata->buck125_gpios[1]) ||
				!gpio_is_valid(pdata->buck125_gpios[2])) {
			dev_err(&pdev->dev, "GPIO NOT VALID\n");
			ret = -EINVAL;
			goto err_out;
		}

		ret = devm_gpio_request(&pdev->dev, pdata->buck125_gpios[0],
					"MAX8997 SET1");
		if (ret)
			goto err_out;

		ret = devm_gpio_request(&pdev->dev, pdata->buck125_gpios[1],
					"MAX8997 SET2");
		if (ret)
			goto err_out;

		ret = devm_gpio_request(&pdev->dev, pdata->buck125_gpios[2],
				"MAX8997 SET3");
		if (ret)
			goto err_out;

		gpio_direction_output(pdata->buck125_gpios[0],
				(max8997->buck125_gpioindex >> 2)
				& 0x1); /* SET1 */
		gpio_direction_output(pdata->buck125_gpios[1],
				(max8997->buck125_gpioindex >> 1)
				& 0x1); /* SET2 */
		gpio_direction_output(pdata->buck125_gpios[2],
				(max8997->buck125_gpioindex >> 0)
				& 0x1); /* SET3 */
	}

	/* DVS-GPIO disabled */
	max8997_update_reg(i2c, MAX8997_REG_BUCK1CTRL, (pdata->buck1_gpiodvs) ?
			(1 << 1) : (0 << 1), 1 << 1);
	max8997_update_reg(i2c, MAX8997_REG_BUCK2CTRL, (pdata->buck2_gpiodvs) ?
			(1 << 1) : (0 << 1), 1 << 1);
	max8997_update_reg(i2c, MAX8997_REG_BUCK5CTRL, (pdata->buck5_gpiodvs) ?
			(1 << 1) : (0 << 1), 1 << 1);

	/* Initialize all the DVS related BUCK registers */
	for (i = 0; i < 8; i++) {
		max8997_update_reg(i2c, MAX8997_REG_BUCK1DVS1 + i,
				max8997->buck1_vol[i],
				0x3f);
		max8997_update_reg(i2c, MAX8997_REG_BUCK2DVS1 + i,
				max8997->buck2_vol[i],
				0x3f);
		max8997_update_reg(i2c, MAX8997_REG_BUCK5DVS1 + i,
				max8997->buck5_vol[i],
				0x3f);
	}

	/* Misc Settings */
	max8997->ramp_delay = 10; /* set 10mV/us, which is the default */
	max8997_write_reg(i2c, MAX8997_REG_BUCKRAMP, (0xf << 4) | 0x9);

	for (i = 0; i < pdata->num_regulators; i++) {
		const struct voltage_map_desc *desc;
		int id = pdata->regulators[i].id;

		desc = reg_voltage_map[id];
		if (desc)
			regulators[id].n_voltages =
				(desc->max - desc->min) / desc->step + 1;
		else if (id == MAX8997_ESAFEOUT1 || id == MAX8997_ESAFEOUT2)
			regulators[id].n_voltages = 4;
		else if (id == MAX8997_CHARGER_CV)
			regulators[id].n_voltages = 16;

		config.dev = max8997->dev;
		config.init_data = pdata->regulators[i].initdata;
		config.driver_data = max8997;

		rdev[i] = regulator_register(&regulators[id], &config);
		if (IS_ERR(rdev[i])) {
			ret = PTR_ERR(rdev[i]);
			dev_err(max8997->dev, "regulator init failed for %d\n",
					id);
			rdev[i] = NULL;
			goto err;
		}
	}

	return 0;
err:
	while (--i >= 0)
		regulator_unregister(rdev[i]);
err_out:
	return ret;
}

static int __devexit max8997_pmic_remove(struct platform_device *pdev)
{
	struct max8997_data *max8997 = platform_get_drvdata(pdev);
	struct regulator_dev **rdev = max8997->rdev;
	int i;

	for (i = 0; i < max8997->num_regulators; i++)
		regulator_unregister(rdev[i]);
	return 0;
}

static const struct platform_device_id max8997_pmic_id[] = {
	{ "max8997-pmic", 0},
	{ },
};
MODULE_DEVICE_TABLE(platform, max8997_pmic_id);

static struct platform_driver max8997_pmic_driver = {
	.driver = {
		.name = "max8997-pmic",
		.owner = THIS_MODULE,
	},
	.probe = max8997_pmic_probe,
	.remove = max8997_pmic_remove,
	.id_table = max8997_pmic_id,
};

static int __init max8997_pmic_init(void)
{
	return platform_driver_register(&max8997_pmic_driver);
}
subsys_initcall(max8997_pmic_init);

static void __exit max8997_pmic_cleanup(void)
{
	platform_driver_unregister(&max8997_pmic_driver);
}
module_exit(max8997_pmic_cleanup);

MODULE_DESCRIPTION("MAXIM 8997/8966 Regulator Driver");
MODULE_AUTHOR("MyungJoo Ham <myungjoo.ham@samsung.com>");
MODULE_LICENSE("GPL");