summaryrefslogtreecommitdiffstats
path: root/drivers/regulator/ab3100.c
blob: 438509f55f05eb5b1083a2dc32d3921a382bdb6b (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
/*
 * drivers/regulator/ab3100.c
 *
 * Copyright (C) 2008-2009 ST-Ericsson AB
 * License terms: GNU General Public License (GPL) version 2
 * Low-level control of the AB3100 IC Low Dropout (LDO)
 * regulators, external regulator and buck converter
 * Author: Mattias Wallin <mattias.wallin@stericsson.com>
 * Author: Linus Walleij <linus.walleij@stericsson.com>
 */

#include <linux/module.h>
#include <linux/kernel.h>
#include <linux/init.h>
#include <linux/err.h>
#include <linux/platform_device.h>
#include <linux/regulator/driver.h>
#include <linux/mfd/ab3100.h>
#include <linux/mfd/abx500.h>
#include <linux/of.h>
#include <linux/regulator/of_regulator.h>

/* LDO registers and some handy masking definitions for AB3100 */
#define AB3100_LDO_A		0x40
#define AB3100_LDO_C		0x41
#define AB3100_LDO_D		0x42
#define AB3100_LDO_E		0x43
#define AB3100_LDO_E_SLEEP	0x44
#define AB3100_LDO_F		0x45
#define AB3100_LDO_G		0x46
#define AB3100_LDO_H		0x47
#define AB3100_LDO_H_SLEEP_MODE	0
#define AB3100_LDO_H_SLEEP_EN	2
#define AB3100_LDO_ON		4
#define AB3100_LDO_H_VSEL_AC	5
#define AB3100_LDO_K		0x48
#define AB3100_LDO_EXT		0x49
#define AB3100_BUCK		0x4A
#define AB3100_BUCK_SLEEP	0x4B
#define AB3100_REG_ON_MASK	0x10

/**
 * struct ab3100_regulator
 * A struct passed around the individual regulator functions
 * @platform_device: platform device holding this regulator
 * @dev: handle to the device
 * @plfdata: AB3100 platform data passed in at probe time
 * @regreg: regulator register number in the AB3100
 */
struct ab3100_regulator {
	struct device *dev;
	struct ab3100_platform_data *plfdata;
	u8 regreg;
};

/* The order in which registers are initialized */
static const u8 ab3100_reg_init_order[AB3100_NUM_REGULATORS+2] = {
	AB3100_LDO_A,
	AB3100_LDO_C,
	AB3100_LDO_E,
	AB3100_LDO_E_SLEEP,
	AB3100_LDO_F,
	AB3100_LDO_G,
	AB3100_LDO_H,
	AB3100_LDO_K,
	AB3100_LDO_EXT,
	AB3100_BUCK,
	AB3100_BUCK_SLEEP,
	AB3100_LDO_D,
};

/* Preset (hardware defined) voltages for these regulators */
#define LDO_A_VOLTAGE 2750000
#define LDO_C_VOLTAGE 2650000
#define LDO_D_VOLTAGE 2650000

static const unsigned int ldo_e_buck_typ_voltages[] = {
	1800000,
	1400000,
	1300000,
	1200000,
	1100000,
	1050000,
	900000,
};

static const unsigned int ldo_f_typ_voltages[] = {
	1800000,
	1400000,
	1300000,
	1200000,
	1100000,
	1050000,
	2500000,
	2650000,
};

static const unsigned int ldo_g_typ_voltages[] = {
	2850000,
	2750000,
	1800000,
	1500000,
};

static const unsigned int ldo_h_typ_voltages[] = {
	2750000,
	1800000,
	1500000,
	1200000,
};

static const unsigned int ldo_k_typ_voltages[] = {
	2750000,
	1800000,
};


/* The regulator devices */
static struct ab3100_regulator
ab3100_regulators[AB3100_NUM_REGULATORS] = {
	{
		.regreg = AB3100_LDO_A,
	},
	{
		.regreg = AB3100_LDO_C,
	},
	{
		.regreg = AB3100_LDO_D,
	},
	{
		.regreg = AB3100_LDO_E,
	},
	{
		.regreg = AB3100_LDO_F,
	},
	{
		.regreg = AB3100_LDO_G,
	},
	{
		.regreg = AB3100_LDO_H,
	},
	{
		.regreg = AB3100_LDO_K,
	},
	{
		.regreg = AB3100_LDO_EXT,
		/* No voltages for the external regulator */
	},
	{
		.regreg = AB3100_BUCK,
	},
};

/*
 * General functions for enable, disable and is_enabled used for
 * LDO: A,C,E,F,G,H,K,EXT and BUCK
 */
static int ab3100_enable_regulator(struct regulator_dev *reg)
{
	struct ab3100_regulator *abreg = rdev_get_drvdata(reg);
	int err;
	u8 regval;

	err = abx500_get_register_interruptible(abreg->dev, 0, abreg->regreg,
						&regval);
	if (err) {
		dev_warn(&reg->dev, "failed to get regid %d value\n",
			 abreg->regreg);
		return err;
	}

	/* The regulator is already on, no reason to go further */
	if (regval & AB3100_REG_ON_MASK)
		return 0;

	regval |= AB3100_REG_ON_MASK;

	err = abx500_set_register_interruptible(abreg->dev, 0, abreg->regreg,
						regval);
	if (err) {
		dev_warn(&reg->dev, "failed to set regid %d value\n",
			 abreg->regreg);
		return err;
	}

	return 0;
}

static int ab3100_disable_regulator(struct regulator_dev *reg)
{
	struct ab3100_regulator *abreg = rdev_get_drvdata(reg);
	int err;
	u8 regval;

	/*
	 * LDO D is a special regulator. When it is disabled, the entire
	 * system is shut down. So this is handled specially.
	 */
	pr_info("Called ab3100_disable_regulator\n");
	if (abreg->regreg == AB3100_LDO_D) {
		dev_info(&reg->dev, "disabling LDO D - shut down system\n");
		/* Setting LDO D to 0x00 cuts the power to the SoC */
		return abx500_set_register_interruptible(abreg->dev, 0,
							 AB3100_LDO_D, 0x00U);
	}

	/*
	 * All other regulators are handled here
	 */
	err = abx500_get_register_interruptible(abreg->dev, 0, abreg->regreg,
						&regval);
	if (err) {
		dev_err(&reg->dev, "unable to get register 0x%x\n",
			abreg->regreg);
		return err;
	}
	regval &= ~AB3100_REG_ON_MASK;
	return abx500_set_register_interruptible(abreg->dev, 0, abreg->regreg,
						 regval);
}

static int ab3100_is_enabled_regulator(struct regulator_dev *reg)
{
	struct ab3100_regulator *abreg = rdev_get_drvdata(reg);
	u8 regval;
	int err;

	err = abx500_get_register_interruptible(abreg->dev, 0, abreg->regreg,
						&regval);
	if (err) {
		dev_err(&reg->dev, "unable to get register 0x%x\n",
			abreg->regreg);
		return err;
	}

	return regval & AB3100_REG_ON_MASK;
}

static int ab3100_get_voltage_regulator(struct regulator_dev *reg)
{
	struct ab3100_regulator *abreg = rdev_get_drvdata(reg);
	u8 regval;
	int err;

	/*
	 * For variable types, read out setting and index into
	 * supplied voltage list.
	 */
	err = abx500_get_register_interruptible(abreg->dev, 0,
						abreg->regreg, &regval);
	if (err) {
		dev_warn(&reg->dev,
			 "failed to get regulator value in register %02x\n",
			 abreg->regreg);
		return err;
	}

	/* The 3 highest bits index voltages */
	regval &= 0xE0;
	regval >>= 5;

	if (regval >= reg->desc->n_voltages) {
		dev_err(&reg->dev,
			"regulator register %02x contains an illegal voltage setting\n",
			abreg->regreg);
		return -EINVAL;
	}

	return reg->desc->volt_table[regval];
}

static int ab3100_set_voltage_regulator_sel(struct regulator_dev *reg,
					    unsigned selector)
{
	struct ab3100_regulator *abreg = rdev_get_drvdata(reg);
	u8 regval;
	int err;

	err = abx500_get_register_interruptible(abreg->dev, 0,
						abreg->regreg, &regval);
	if (err) {
		dev_warn(&reg->dev,
			 "failed to get regulator register %02x\n",
			 abreg->regreg);
		return err;
	}

	/* The highest three bits control the variable regulators */
	regval &= ~0xE0;
	regval |= (selector << 5);

	err = abx500_set_register_interruptible(abreg->dev, 0,
						abreg->regreg, regval);
	if (err)
		dev_warn(&reg->dev, "failed to set regulator register %02x\n",
			abreg->regreg);

	return err;
}

static int ab3100_set_suspend_voltage_regulator(struct regulator_dev *reg,
						int uV)
{
	struct ab3100_regulator *abreg = rdev_get_drvdata(reg);
	u8 regval;
	int err;
	int bestindex;
	u8 targetreg;

	if (abreg->regreg == AB3100_LDO_E)
		targetreg = AB3100_LDO_E_SLEEP;
	else if (abreg->regreg == AB3100_BUCK)
		targetreg = AB3100_BUCK_SLEEP;
	else
		return -EINVAL;

	/* LDO E and BUCK have special suspend voltages you can set */
	bestindex = regulator_map_voltage_iterate(reg, uV, uV);

	err = abx500_get_register_interruptible(abreg->dev, 0,
						targetreg, &regval);
	if (err) {
		dev_warn(&reg->dev,
			 "failed to get regulator register %02x\n",
			 targetreg);
		return err;
	}

	/* The highest three bits control the variable regulators */
	regval &= ~0xE0;
	regval |= (bestindex << 5);

	err = abx500_set_register_interruptible(abreg->dev, 0,
						targetreg, regval);
	if (err)
		dev_warn(&reg->dev, "failed to set regulator register %02x\n",
			abreg->regreg);

	return err;
}

/*
 * The external regulator can just define a fixed voltage.
 */
static int ab3100_get_voltage_regulator_external(struct regulator_dev *reg)
{
	struct ab3100_regulator *abreg = rdev_get_drvdata(reg);

	if (abreg->plfdata)
		return abreg->plfdata->external_voltage;
	else
		/* TODO: encode external voltage into device tree */
		return 0;
}

static const struct regulator_ops regulator_ops_fixed = {
	.enable      = ab3100_enable_regulator,
	.disable     = ab3100_disable_regulator,
	.is_enabled  = ab3100_is_enabled_regulator,
};

static const struct regulator_ops regulator_ops_variable = {
	.enable      = ab3100_enable_regulator,
	.disable     = ab3100_disable_regulator,
	.is_enabled  = ab3100_is_enabled_regulator,
	.get_voltage = ab3100_get_voltage_regulator,
	.set_voltage_sel = ab3100_set_voltage_regulator_sel,
	.list_voltage = regulator_list_voltage_table,
};

static const struct regulator_ops regulator_ops_variable_sleepable = {
	.enable      = ab3100_enable_regulator,
	.disable     = ab3100_disable_regulator,
	.is_enabled  = ab3100_is_enabled_regulator,
	.get_voltage = ab3100_get_voltage_regulator,
	.set_voltage_sel = ab3100_set_voltage_regulator_sel,
	.set_suspend_voltage = ab3100_set_suspend_voltage_regulator,
	.list_voltage = regulator_list_voltage_table,
};

/*
 * LDO EXT is an external regulator so it is really
 * not possible to set any voltage locally here, AB3100
 * is an on/off switch plain an simple. The external
 * voltage is defined in the board set-up if any.
 */
static const struct regulator_ops regulator_ops_external = {
	.enable      = ab3100_enable_regulator,
	.disable     = ab3100_disable_regulator,
	.is_enabled  = ab3100_is_enabled_regulator,
	.get_voltage = ab3100_get_voltage_regulator_external,
};

static const struct regulator_desc
ab3100_regulator_desc[AB3100_NUM_REGULATORS] = {
	{
		.name = "LDO_A",
		.id   = AB3100_LDO_A,
		.ops  = &regulator_ops_fixed,
		.n_voltages = 1,
		.type = REGULATOR_VOLTAGE,
		.owner = THIS_MODULE,
		.fixed_uV = LDO_A_VOLTAGE,
		.enable_time = 200,
	},
	{
		.name = "LDO_C",
		.id   = AB3100_LDO_C,
		.ops  = &regulator_ops_fixed,
		.n_voltages = 1,
		.type = REGULATOR_VOLTAGE,
		.owner = THIS_MODULE,
		.fixed_uV = LDO_C_VOLTAGE,
		.enable_time = 200,
	},
	{
		.name = "LDO_D",
		.id   = AB3100_LDO_D,
		.ops  = &regulator_ops_fixed,
		.n_voltages = 1,
		.type = REGULATOR_VOLTAGE,
		.owner = THIS_MODULE,
		.fixed_uV = LDO_D_VOLTAGE,
		.enable_time = 200,
	},
	{
		.name = "LDO_E",
		.id   = AB3100_LDO_E,
		.ops  = &regulator_ops_variable_sleepable,
		.n_voltages = ARRAY_SIZE(ldo_e_buck_typ_voltages),
		.volt_table = ldo_e_buck_typ_voltages,
		.type = REGULATOR_VOLTAGE,
		.owner = THIS_MODULE,
		.enable_time = 200,
	},
	{
		.name = "LDO_F",
		.id   = AB3100_LDO_F,
		.ops  = &regulator_ops_variable,
		.n_voltages = ARRAY_SIZE(ldo_f_typ_voltages),
		.volt_table = ldo_f_typ_voltages,
		.type = REGULATOR_VOLTAGE,
		.owner = THIS_MODULE,
		.enable_time = 600,
	},
	{
		.name = "LDO_G",
		.id   = AB3100_LDO_G,
		.ops  = &regulator_ops_variable,
		.n_voltages = ARRAY_SIZE(ldo_g_typ_voltages),
		.volt_table = ldo_g_typ_voltages,
		.type = REGULATOR_VOLTAGE,
		.owner = THIS_MODULE,
		.enable_time = 400,
	},
	{
		.name = "LDO_H",
		.id   = AB3100_LDO_H,
		.ops  = &regulator_ops_variable,
		.n_voltages = ARRAY_SIZE(ldo_h_typ_voltages),
		.volt_table = ldo_h_typ_voltages,
		.type = REGULATOR_VOLTAGE,
		.owner = THIS_MODULE,
		.enable_time = 200,
	},
	{
		.name = "LDO_K",
		.id   = AB3100_LDO_K,
		.ops  = &regulator_ops_variable,
		.n_voltages = ARRAY_SIZE(ldo_k_typ_voltages),
		.volt_table = ldo_k_typ_voltages,
		.type = REGULATOR_VOLTAGE,
		.owner = THIS_MODULE,
		.enable_time = 200,
	},
	{
		.name = "LDO_EXT",
		.id   = AB3100_LDO_EXT,
		.ops  = &regulator_ops_external,
		.type = REGULATOR_VOLTAGE,
		.owner = THIS_MODULE,
	},
	{
		.name = "BUCK",
		.id   = AB3100_BUCK,
		.ops  = &regulator_ops_variable_sleepable,
		.n_voltages = ARRAY_SIZE(ldo_e_buck_typ_voltages),
		.volt_table = ldo_e_buck_typ_voltages,
		.type = REGULATOR_VOLTAGE,
		.owner = THIS_MODULE,
		.enable_time = 1000,
	},
};

static int ab3100_regulator_register(struct platform_device *pdev,
				     struct ab3100_platform_data *plfdata,
				     struct regulator_init_data *init_data,
				     struct device_node *np,
				     unsigned long id)
{
	const struct regulator_desc *desc;
	struct ab3100_regulator *reg;
	struct regulator_dev *rdev;
	struct regulator_config config = { };
	int err, i;

	for (i = 0; i < AB3100_NUM_REGULATORS; i++) {
		desc = &ab3100_regulator_desc[i];
		if (desc->id == id)
			break;
	}
	if (desc->id != id)
		return -ENODEV;

	/* Same index used for this array */
	reg = &ab3100_regulators[i];

	/*
	 * Initialize per-regulator struct.
	 * Inherit platform data, this comes down from the
	 * i2c boarddata, from the machine. So if you want to
	 * see what it looks like for a certain machine, go
	 * into the machine I2C setup.
	 */
	reg->dev = &pdev->dev;
	if (plfdata) {
		reg->plfdata = plfdata;
		config.init_data = &plfdata->reg_constraints[i];
	} else if (np) {
		config.of_node = np;
		config.init_data = init_data;
	}
	config.dev = &pdev->dev;
	config.driver_data = reg;

	rdev = devm_regulator_register(&pdev->dev, desc, &config);
	if (IS_ERR(rdev)) {
		err = PTR_ERR(rdev);
		dev_err(&pdev->dev,
			"%s: failed to register regulator %s err %d\n",
			__func__, desc->name,
			err);
		return err;
	}

	return 0;
}

static struct of_regulator_match ab3100_regulator_matches[] = {
	{ .name = "ab3100_ldo_a", .driver_data = (void *) AB3100_LDO_A, },
	{ .name = "ab3100_ldo_c", .driver_data = (void *) AB3100_LDO_C, },
	{ .name = "ab3100_ldo_d", .driver_data = (void *) AB3100_LDO_D, },
	{ .name = "ab3100_ldo_e", .driver_data = (void *) AB3100_LDO_E, },
	{ .name = "ab3100_ldo_f", .driver_data = (void *) AB3100_LDO_F },
	{ .name = "ab3100_ldo_g", .driver_data = (void *) AB3100_LDO_G },
	{ .name = "ab3100_ldo_h", .driver_data = (void *) AB3100_LDO_H },
	{ .name = "ab3100_ldo_k", .driver_data = (void *) AB3100_LDO_K },
	{ .name = "ab3100_ext", .driver_data = (void *) AB3100_LDO_EXT },
	{ .name = "ab3100_buck", .driver_data = (void *) AB3100_BUCK },
};

/*
 * Initial settings of ab3100 registers.
 * Common for below LDO regulator settings are that
 * bit 7-5 controls voltage. Bit 4 turns regulator ON(1) or OFF(0).
 * Bit 3-2 controls sleep enable and bit 1-0 controls sleep mode.
 */
/* LDO_A 0x16: 2.75V, ON, SLEEP_A, SLEEP OFF GND */
#define LDO_A_SETTING		0x16
/* LDO_C 0x10: 2.65V, ON, SLEEP_A or B, SLEEP full power */
#define LDO_C_SETTING		0x10
/* LDO_D 0x10: 2.65V, ON, sleep mode not used */
#define LDO_D_SETTING		0x10
/* LDO_E 0x10: 1.8V, ON, SLEEP_A or B, SLEEP full power */
#define LDO_E_SETTING		0x10
/* LDO_E SLEEP 0x00: 1.8V, not used, SLEEP_A or B, not used */
#define LDO_E_SLEEP_SETTING	0x00
/* LDO_F 0xD0: 2.5V, ON, SLEEP_A or B, SLEEP full power */
#define LDO_F_SETTING		0xD0
/* LDO_G 0x00: 2.85V, OFF, SLEEP_A or B, SLEEP full power */
#define LDO_G_SETTING		0x00
/* LDO_H 0x18: 2.75V, ON, SLEEP_B, SLEEP full power */
#define LDO_H_SETTING		0x18
/* LDO_K 0x00: 2.75V, OFF, SLEEP_A or B, SLEEP full power */
#define LDO_K_SETTING		0x00
/* LDO_EXT 0x00: Voltage not set, OFF, not used, not used */
#define LDO_EXT_SETTING		0x00
/* BUCK 0x7D: 1.2V, ON, SLEEP_A and B, SLEEP low power */
#define BUCK_SETTING	0x7D
/* BUCK SLEEP 0xAC: 1.05V, Not used, SLEEP_A and B, Not used */
#define BUCK_SLEEP_SETTING	0xAC

static const u8 ab3100_reg_initvals[] = {
	LDO_A_SETTING,
	LDO_C_SETTING,
	LDO_E_SETTING,
	LDO_E_SLEEP_SETTING,
	LDO_F_SETTING,
	LDO_G_SETTING,
	LDO_H_SETTING,
	LDO_K_SETTING,
	LDO_EXT_SETTING,
	BUCK_SETTING,
	BUCK_SLEEP_SETTING,
	LDO_D_SETTING,
};

static int
ab3100_regulator_of_probe(struct platform_device *pdev, struct device_node *np)
{
	int err, i;

	/*
	 * Set up the regulator registers, as was previously done with
	 * platform data.
	 */
	/* Set up regulators */
	for (i = 0; i < ARRAY_SIZE(ab3100_reg_init_order); i++) {
		err = abx500_set_register_interruptible(&pdev->dev, 0,
					ab3100_reg_init_order[i],
					ab3100_reg_initvals[i]);
		if (err) {
			dev_err(&pdev->dev, "regulator initialization failed with error %d\n",
				err);
			return err;
		}
	}

	for (i = 0; i < ARRAY_SIZE(ab3100_regulator_matches); i++) {
		err = ab3100_regulator_register(
			pdev, NULL, ab3100_regulator_matches[i].init_data,
			ab3100_regulator_matches[i].of_node,
			(unsigned long)ab3100_regulator_matches[i].driver_data);
		if (err)
			return err;
	}

	return 0;
}


static int ab3100_regulators_probe(struct platform_device *pdev)
{
	struct ab3100_platform_data *plfdata = dev_get_platdata(&pdev->dev);
	struct device_node *np = pdev->dev.of_node;
	int err = 0;
	u8 data;
	int i;

	/* Check chip state */
	err = abx500_get_register_interruptible(&pdev->dev, 0,
						AB3100_LDO_D, &data);
	if (err) {
		dev_err(&pdev->dev, "could not read initial status of LDO_D\n");
		return err;
	}
	if (data & 0x10)
		dev_notice(&pdev->dev,
			   "chip is already in active mode (Warm start)\n");
	else
		dev_notice(&pdev->dev,
			   "chip is in inactive mode (Cold start)\n");

	if (np) {
		err = of_regulator_match(&pdev->dev, np,
					 ab3100_regulator_matches,
					 ARRAY_SIZE(ab3100_regulator_matches));
		if (err < 0) {
			dev_err(&pdev->dev,
				"Error parsing regulator init data: %d\n", err);
			return err;
		}
		return ab3100_regulator_of_probe(pdev, np);
	}

	/* Set up regulators */
	for (i = 0; i < ARRAY_SIZE(ab3100_reg_init_order); i++) {
		err = abx500_set_register_interruptible(&pdev->dev, 0,
					ab3100_reg_init_order[i],
					plfdata->reg_initvals[i]);
		if (err) {
			dev_err(&pdev->dev, "regulator initialization failed with error %d\n",
				err);
			return err;
		}
	}

	/* Register the regulators */
	for (i = 0; i < AB3100_NUM_REGULATORS; i++) {
		const struct regulator_desc *desc = &ab3100_regulator_desc[i];

		err = ab3100_regulator_register(pdev, plfdata, NULL, NULL,
						desc->id);
		if (err)
			return err;
	}

	return 0;
}

static struct platform_driver ab3100_regulators_driver = {
	.driver = {
		.name  = "ab3100-regulators",
	},
	.probe = ab3100_regulators_probe,
};

static __init int ab3100_regulators_init(void)
{
	return platform_driver_register(&ab3100_regulators_driver);
}

static __exit void ab3100_regulators_exit(void)
{
	platform_driver_unregister(&ab3100_regulators_driver);
}

subsys_initcall(ab3100_regulators_init);
module_exit(ab3100_regulators_exit);

MODULE_AUTHOR("Mattias Wallin <mattias.wallin@stericsson.com>");
MODULE_DESCRIPTION("AB3100 Regulator driver");
MODULE_LICENSE("GPL");
MODULE_ALIAS("platform:ab3100-regulators");