summaryrefslogtreecommitdiff
path: root/drivers/power/supply/cpcap-battery.c
blob: 98ba07869c3b00afb16d8f4d71d4ece9f855c40d (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
/*
 * Battery driver for CPCAP PMIC
 *
 * Copyright (C) 2017 Tony Lindgren <tony@atomide.com>
 *
 * Some parts of the code based on earlie Motorola mapphone Linux kernel
 * drivers:
 *
 * Copyright (C) 2009-2010 Motorola, Inc.
 *
 * 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.

 * This program is distributed "as is" WITHOUT ANY WARRANTY of any
 * kind, whether express or implied; without even the implied warranty
 * of MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
 * GNU General Public License for more details.
 */

#include <linux/delay.h>
#include <linux/err.h>
#include <linux/interrupt.h>
#include <linux/kernel.h>
#include <linux/module.h>
#include <linux/of_device.h>
#include <linux/platform_device.h>
#include <linux/power_supply.h>
#include <linux/reboot.h>
#include <linux/regmap.h>

#include <linux/iio/consumer.h>
#include <linux/iio/types.h>
#include <linux/mfd/motorola-cpcap.h>

#include <asm/div64.h>

/*
 * Register bit defines for CPCAP_REG_BPEOL. Some of these seem to
 * map to MC13783UG.pdf "Table 5-19. Register 13, Power Control 0"
 * to enable BATTDETEN, LOBAT and EOL features. We currently use
 * LOBAT interrupts instead of EOL.
 */
#define CPCAP_REG_BPEOL_BIT_EOL9	BIT(9)	/* Set for EOL irq */
#define CPCAP_REG_BPEOL_BIT_EOL8	BIT(8)	/* Set for EOL irq */
#define CPCAP_REG_BPEOL_BIT_UNKNOWN7	BIT(7)
#define CPCAP_REG_BPEOL_BIT_UNKNOWN6	BIT(6)
#define CPCAP_REG_BPEOL_BIT_UNKNOWN5	BIT(5)
#define CPCAP_REG_BPEOL_BIT_EOL_MULTI	BIT(4)	/* Set for multiple EOL irqs */
#define CPCAP_REG_BPEOL_BIT_UNKNOWN3	BIT(3)
#define CPCAP_REG_BPEOL_BIT_UNKNOWN2	BIT(2)
#define CPCAP_REG_BPEOL_BIT_BATTDETEN	BIT(1)	/* Enable battery detect */
#define CPCAP_REG_BPEOL_BIT_EOLSEL	BIT(0)	/* BPDET = 0, EOL = 1 */

#define CPCAP_BATTERY_CC_SAMPLE_PERIOD_MS	250

enum {
	CPCAP_BATTERY_IIO_BATTDET,
	CPCAP_BATTERY_IIO_VOLTAGE,
	CPCAP_BATTERY_IIO_CHRG_CURRENT,
	CPCAP_BATTERY_IIO_BATT_CURRENT,
	CPCAP_BATTERY_IIO_NR,
};

enum cpcap_battery_irq_action {
	CPCAP_BATTERY_IRQ_ACTION_NONE,
	CPCAP_BATTERY_IRQ_ACTION_BATTERY_LOW,
	CPCAP_BATTERY_IRQ_ACTION_POWEROFF,
};

struct cpcap_interrupt_desc {
	const char *name;
	struct list_head node;
	int irq;
	enum cpcap_battery_irq_action action;
};

struct cpcap_battery_config {
	int ccm;
	int cd_factor;
	struct power_supply_info info;
};

struct cpcap_coulomb_counter_data {
	s32 sample;		/* 24-bits */
	s32 accumulator;
	s16 offset;		/* 10-bits */
};

enum cpcap_battery_state {
	CPCAP_BATTERY_STATE_PREVIOUS,
	CPCAP_BATTERY_STATE_LATEST,
	CPCAP_BATTERY_STATE_NR,
};

struct cpcap_battery_state_data {
	int voltage;
	int current_ua;
	int counter_uah;
	int temperature;
	ktime_t time;
	struct cpcap_coulomb_counter_data cc;
};

struct cpcap_battery_ddata {
	struct device *dev;
	struct regmap *reg;
	struct list_head irq_list;
	struct iio_channel *channels[CPCAP_BATTERY_IIO_NR];
	struct power_supply *psy;
	struct cpcap_battery_config config;
	struct cpcap_battery_state_data state[CPCAP_BATTERY_STATE_NR];
	atomic_t active;
	int status;
	u16 vendor;
};

#define CPCAP_NO_BATTERY	-400

static struct cpcap_battery_state_data *
cpcap_battery_get_state(struct cpcap_battery_ddata *ddata,
			enum cpcap_battery_state state)
{
	if (state >= CPCAP_BATTERY_STATE_NR)
		return NULL;

	return &ddata->state[state];
}

static struct cpcap_battery_state_data *
cpcap_battery_latest(struct cpcap_battery_ddata *ddata)
{
	return cpcap_battery_get_state(ddata, CPCAP_BATTERY_STATE_LATEST);
}

static struct cpcap_battery_state_data *
cpcap_battery_previous(struct cpcap_battery_ddata *ddata)
{
	return cpcap_battery_get_state(ddata, CPCAP_BATTERY_STATE_PREVIOUS);
}

static int cpcap_charger_battery_temperature(struct cpcap_battery_ddata *ddata,
					     int *value)
{
	struct iio_channel *channel;
	int error;

	channel = ddata->channels[CPCAP_BATTERY_IIO_BATTDET];
	error = iio_read_channel_processed(channel, value);
	if (error < 0) {
		dev_warn(ddata->dev, "%s failed: %i\n", __func__, error);
		*value = CPCAP_NO_BATTERY;

		return error;
	}

	*value /= 100;

	return 0;
}

static int cpcap_battery_get_voltage(struct cpcap_battery_ddata *ddata)
{
	struct iio_channel *channel;
	int error, value = 0;

	channel = ddata->channels[CPCAP_BATTERY_IIO_VOLTAGE];
	error = iio_read_channel_processed(channel, &value);
	if (error < 0) {
		dev_warn(ddata->dev, "%s failed: %i\n", __func__, error);

		return 0;
	}

	return value * 1000;
}

static int cpcap_battery_get_current(struct cpcap_battery_ddata *ddata)
{
	struct iio_channel *channel;
	int error, value = 0;

	channel = ddata->channels[CPCAP_BATTERY_IIO_BATT_CURRENT];
	error = iio_read_channel_processed(channel, &value);
	if (error < 0) {
		dev_warn(ddata->dev, "%s failed: %i\n", __func__, error);

		return 0;
	}

	return value * 1000;
}

/**
 * cpcap_battery_cc_raw_div - calculate and divide coulomb counter μAms values
 * @ddata: device driver data
 * @sample: coulomb counter sample value
 * @accumulator: coulomb counter integrator value
 * @offset: coulomb counter offset value
 * @divider: conversion divider
 *
 * Note that cc_lsb and cc_dur values are from Motorola Linux kernel
 * function data_get_avg_curr_ua() and seem to be based on measured test
 * results. It also has the following comment:
 *
 * Adjustment factors are applied here as a temp solution per the test
 * results. Need to work out a formal solution for this adjustment.
 *
 * A coulomb counter for similar hardware seems to be documented in
 * "TWL6030 Gas Gauging Basics (Rev. A)" swca095a.pdf in chapter
 * "10 Calculating Accumulated Current". We however follow what the
 * Motorola mapphone Linux kernel is doing as there may be either a
 * TI or ST coulomb counter in the PMIC.
 */
static int cpcap_battery_cc_raw_div(struct cpcap_battery_ddata *ddata,
				    u32 sample, s32 accumulator,
				    s16 offset, u32 divider)
{
	s64 acc;
	u64 tmp;
	int avg_current;
	u32 cc_lsb;

	sample &= 0xffffff;		/* 24-bits, unsigned */
	offset &= 0x7ff;		/* 10-bits, signed */

	switch (ddata->vendor) {
	case CPCAP_VENDOR_ST:
		cc_lsb = 95374;		/* μAms per LSB */
		break;
	case CPCAP_VENDOR_TI:
		cc_lsb = 91501;		/* μAms per LSB */
		break;
	default:
		return -EINVAL;
	}

	acc = accumulator;
	acc = acc - ((s64)sample * offset);
	cc_lsb = (cc_lsb * ddata->config.cd_factor) / 1000;

	if (acc >=  0)
		tmp = acc;
	else
		tmp = acc * -1;

	tmp = tmp * cc_lsb;
	do_div(tmp, divider);
	avg_current = tmp;

	if (acc >= 0)
		return -avg_current;
	else
		return avg_current;
}

/* 3600000μAms = 1μAh */
static int cpcap_battery_cc_to_uah(struct cpcap_battery_ddata *ddata,
				   u32 sample, s32 accumulator,
				   s16 offset)
{
	return cpcap_battery_cc_raw_div(ddata, sample,
					accumulator, offset,
					3600000);
}

static int cpcap_battery_cc_to_ua(struct cpcap_battery_ddata *ddata,
				  u32 sample, s32 accumulator,
				  s16 offset)
{
	return cpcap_battery_cc_raw_div(ddata, sample,
					accumulator, offset,
					sample *
					CPCAP_BATTERY_CC_SAMPLE_PERIOD_MS);
}

/**
 * cpcap_battery_read_accumulated - reads cpcap coulomb counter
 * @ddata: device driver data
 * @regs: coulomb counter values
 *
 * Based on Motorola mapphone kernel function data_read_regs().
 * Looking at the registers, the coulomb counter seems similar to
 * the coulomb counter in TWL6030. See "TWL6030 Gas Gauging Basics
 * (Rev. A) swca095a.pdf for "10 Calculating Accumulated Current".
 *
 * Note that swca095a.pdf instructs to stop the coulomb counter
 * before reading to avoid values changing. Motorola mapphone
 * Linux kernel does not do it, so let's assume they've verified
 * the data produced is correct.
 */
static int
cpcap_battery_read_accumulated(struct cpcap_battery_ddata *ddata,
			       struct cpcap_coulomb_counter_data *ccd)
{
	u16 buf[7];	/* CPCAP_REG_CC1 to CCI */
	int error;

	ccd->sample = 0;
	ccd->accumulator = 0;
	ccd->offset = 0;

	/* Read coulomb counter register range */
	error = regmap_bulk_read(ddata->reg, CPCAP_REG_CCS1,
				 buf, ARRAY_SIZE(buf));
	if (error)
		return 0;

	/* Sample value CPCAP_REG_CCS1 & 2 */
	ccd->sample = (buf[1] & 0x0fff) << 16;
	ccd->sample |= buf[0];

	/* Accumulator value CPCAP_REG_CCA1 & 2 */
	ccd->accumulator = ((s16)buf[3]) << 16;
	ccd->accumulator |= buf[2];

	/* Offset value CPCAP_REG_CCO */
	ccd->offset = buf[5];

	/* Adjust offset based on mode value CPCAP_REG_CCM? */
	if (buf[4] >= 0x200)
		ccd->offset |= 0xfc00;

	return cpcap_battery_cc_to_uah(ddata,
				       ccd->sample,
				       ccd->accumulator,
				       ccd->offset);
}

/**
 * cpcap_battery_cc_get_avg_current - read cpcap coulumb counter
 * @ddata: cpcap battery driver device data
 */
static int cpcap_battery_cc_get_avg_current(struct cpcap_battery_ddata *ddata)
{
	int value, acc, error;
	s32 sample = 1;
	s16 offset;

	if (ddata->vendor == CPCAP_VENDOR_ST)
		sample = 4;

	/* Coulomb counter integrator */
	error = regmap_read(ddata->reg, CPCAP_REG_CCI, &value);
	if (error)
		return error;

	if ((ddata->vendor == CPCAP_VENDOR_TI) && (value > 0x2000))
		value = value | 0xc000;

	acc = (s16)value;

	/* Coulomb counter sample time */
	error = regmap_read(ddata->reg, CPCAP_REG_CCM, &value);
	if (error)
		return error;

	if (value < 0x200)
		offset = value;
	else
		offset = value | 0xfc00;

	return cpcap_battery_cc_to_ua(ddata, sample, acc, offset);
}

static bool cpcap_battery_full(struct cpcap_battery_ddata *ddata)
{
	struct cpcap_battery_state_data *state = cpcap_battery_latest(ddata);

	/* Basically anything that measures above 4347000 is full */
	if (state->voltage >= (ddata->config.info.voltage_max_design - 4000))
		return true;

	return false;
}

static int cpcap_battery_update_status(struct cpcap_battery_ddata *ddata)
{
	struct cpcap_battery_state_data state, *latest, *previous;
	ktime_t now;
	int error;

	memset(&state, 0, sizeof(state));
	now = ktime_get();

	latest = cpcap_battery_latest(ddata);
	if (latest) {
		s64 delta_ms = ktime_to_ms(ktime_sub(now, latest->time));

		if (delta_ms < CPCAP_BATTERY_CC_SAMPLE_PERIOD_MS)
			return delta_ms;
	}

	state.time = now;
	state.voltage = cpcap_battery_get_voltage(ddata);
	state.current_ua = cpcap_battery_get_current(ddata);
	state.counter_uah = cpcap_battery_read_accumulated(ddata, &state.cc);

	error = cpcap_charger_battery_temperature(ddata,
						  &state.temperature);
	if (error)
		return error;

	previous = cpcap_battery_previous(ddata);
	memcpy(previous, latest, sizeof(*previous));
	memcpy(latest, &state, sizeof(*latest));

	return 0;
}

static enum power_supply_property cpcap_battery_props[] = {
	POWER_SUPPLY_PROP_STATUS,
	POWER_SUPPLY_PROP_PRESENT,
	POWER_SUPPLY_PROP_TECHNOLOGY,
	POWER_SUPPLY_PROP_VOLTAGE_NOW,
	POWER_SUPPLY_PROP_VOLTAGE_MAX_DESIGN,
	POWER_SUPPLY_PROP_VOLTAGE_MIN_DESIGN,
	POWER_SUPPLY_PROP_CURRENT_AVG,
	POWER_SUPPLY_PROP_CURRENT_NOW,
	POWER_SUPPLY_PROP_CHARGE_FULL_DESIGN,
	POWER_SUPPLY_PROP_CHARGE_COUNTER,
	POWER_SUPPLY_PROP_POWER_NOW,
	POWER_SUPPLY_PROP_POWER_AVG,
	POWER_SUPPLY_PROP_CAPACITY_LEVEL,
	POWER_SUPPLY_PROP_SCOPE,
	POWER_SUPPLY_PROP_TEMP,
};

static int cpcap_battery_get_property(struct power_supply *psy,
				      enum power_supply_property psp,
				      union power_supply_propval *val)
{
	struct cpcap_battery_ddata *ddata = power_supply_get_drvdata(psy);
	struct cpcap_battery_state_data *latest, *previous;
	u32 sample;
	s32 accumulator;
	int cached;
	s64 tmp;

	cached = cpcap_battery_update_status(ddata);
	if (cached < 0)
		return cached;

	latest = cpcap_battery_latest(ddata);
	previous = cpcap_battery_previous(ddata);

	switch (psp) {
	case POWER_SUPPLY_PROP_PRESENT:
		if (latest->temperature > CPCAP_NO_BATTERY)
			val->intval = 1;
		else
			val->intval = 0;
		break;
	case POWER_SUPPLY_PROP_STATUS:
		if (cpcap_battery_full(ddata)) {
			val->intval = POWER_SUPPLY_STATUS_FULL;
			break;
		}
		if (cpcap_battery_cc_get_avg_current(ddata) < 0)
			val->intval = POWER_SUPPLY_STATUS_CHARGING;
		else
			val->intval = POWER_SUPPLY_STATUS_DISCHARGING;
		break;
	case POWER_SUPPLY_PROP_TECHNOLOGY:
		val->intval = ddata->config.info.technology;
		break;
	case POWER_SUPPLY_PROP_VOLTAGE_NOW:
		val->intval = cpcap_battery_get_voltage(ddata);
		break;
	case POWER_SUPPLY_PROP_VOLTAGE_MAX_DESIGN:
		val->intval = ddata->config.info.voltage_max_design;
		break;
	case POWER_SUPPLY_PROP_VOLTAGE_MIN_DESIGN:
		val->intval = ddata->config.info.voltage_min_design;
		break;
	case POWER_SUPPLY_PROP_CURRENT_AVG:
		if (cached) {
			val->intval = cpcap_battery_cc_get_avg_current(ddata);
			break;
		}
		sample = latest->cc.sample - previous->cc.sample;
		accumulator = latest->cc.accumulator - previous->cc.accumulator;
		val->intval = cpcap_battery_cc_to_ua(ddata, sample,
						     accumulator,
						     latest->cc.offset);
		break;
	case POWER_SUPPLY_PROP_CURRENT_NOW:
		val->intval = latest->current_ua;
		break;
	case POWER_SUPPLY_PROP_CHARGE_COUNTER:
		val->intval = latest->counter_uah;
		break;
	case POWER_SUPPLY_PROP_POWER_NOW:
		tmp = (latest->voltage / 10000) * latest->current_ua;
		val->intval = div64_s64(tmp, 100);
		break;
	case POWER_SUPPLY_PROP_POWER_AVG:
		if (cached) {
			tmp = cpcap_battery_cc_get_avg_current(ddata);
			tmp *= (latest->voltage / 10000);
			val->intval = div64_s64(tmp, 100);
			break;
		}
		sample = latest->cc.sample - previous->cc.sample;
		accumulator = latest->cc.accumulator - previous->cc.accumulator;
		tmp = cpcap_battery_cc_to_ua(ddata, sample, accumulator,
					     latest->cc.offset);
		tmp *= ((latest->voltage + previous->voltage) / 20000);
		val->intval = div64_s64(tmp, 100);
		break;
	case POWER_SUPPLY_PROP_CAPACITY_LEVEL:
		if (cpcap_battery_full(ddata))
			val->intval = POWER_SUPPLY_CAPACITY_LEVEL_FULL;
		else if (latest->voltage >= 3750000)
			val->intval = POWER_SUPPLY_CAPACITY_LEVEL_HIGH;
		else if (latest->voltage >= 3300000)
			val->intval = POWER_SUPPLY_CAPACITY_LEVEL_NORMAL;
		else if (latest->voltage > 3100000)
			val->intval = POWER_SUPPLY_CAPACITY_LEVEL_LOW;
		else if (latest->voltage <= 3100000)
			val->intval = POWER_SUPPLY_CAPACITY_LEVEL_CRITICAL;
		else
			val->intval = POWER_SUPPLY_CAPACITY_LEVEL_UNKNOWN;
		break;
	case POWER_SUPPLY_PROP_CHARGE_FULL_DESIGN:
		val->intval = ddata->config.info.charge_full_design;
		break;
	case POWER_SUPPLY_PROP_SCOPE:
		val->intval = POWER_SUPPLY_SCOPE_SYSTEM;
		break;
	case POWER_SUPPLY_PROP_TEMP:
		val->intval = latest->temperature;
		break;
	default:
		return -EINVAL;
	}

	return 0;
}

static irqreturn_t cpcap_battery_irq_thread(int irq, void *data)
{
	struct cpcap_battery_ddata *ddata = data;
	struct cpcap_battery_state_data *latest;
	struct cpcap_interrupt_desc *d;

	if (!atomic_read(&ddata->active))
		return IRQ_NONE;

	list_for_each_entry(d, &ddata->irq_list, node) {
		if (irq == d->irq)
			break;
	}

	if (!d)
		return IRQ_NONE;

	latest = cpcap_battery_latest(ddata);

	switch (d->action) {
	case CPCAP_BATTERY_IRQ_ACTION_BATTERY_LOW:
		if (latest->counter_uah >= 0)
			dev_warn(ddata->dev, "Battery low at 3.3V!\n");
		break;
	case CPCAP_BATTERY_IRQ_ACTION_POWEROFF:
		if (latest->counter_uah >= 0) {
			dev_emerg(ddata->dev,
				  "Battery empty at 3.1V, powering off\n");
			orderly_poweroff(true);
		}
		break;
	default:
		break;
	}

	power_supply_changed(ddata->psy);

	return IRQ_HANDLED;
}

static int cpcap_battery_init_irq(struct platform_device *pdev,
				  struct cpcap_battery_ddata *ddata,
				  const char *name)
{
	struct cpcap_interrupt_desc *d;
	int irq, error;

	irq = platform_get_irq_byname(pdev, name);
	if (irq < 0)
		return irq;

	error = devm_request_threaded_irq(ddata->dev, irq, NULL,
					  cpcap_battery_irq_thread,
					  IRQF_SHARED,
					  name, ddata);
	if (error) {
		dev_err(ddata->dev, "could not get irq %s: %i\n",
			name, error);

		return error;
	}

	d = devm_kzalloc(ddata->dev, sizeof(*d), GFP_KERNEL);
	if (!d)
		return -ENOMEM;

	d->name = name;
	d->irq = irq;

	if (!strncmp(name, "lowbph", 6))
		d->action = CPCAP_BATTERY_IRQ_ACTION_BATTERY_LOW;
	else if (!strncmp(name, "lowbpl", 6))
		d->action = CPCAP_BATTERY_IRQ_ACTION_POWEROFF;

	list_add(&d->node, &ddata->irq_list);

	return 0;
}

static int cpcap_battery_init_interrupts(struct platform_device *pdev,
					 struct cpcap_battery_ddata *ddata)
{
	const char * const cpcap_battery_irqs[] = {
		"eol", "lowbph", "lowbpl",
		"chrgcurr1", "battdetb"
	};
	int i, error;

	for (i = 0; i < ARRAY_SIZE(cpcap_battery_irqs); i++) {
		error = cpcap_battery_init_irq(pdev, ddata,
					       cpcap_battery_irqs[i]);
		if (error)
			return error;
	}

	/* Enable low battery interrupts for 3.3V high and 3.1V low */
	error = regmap_update_bits(ddata->reg, CPCAP_REG_BPEOL,
				   0xffff,
				   CPCAP_REG_BPEOL_BIT_BATTDETEN);
	if (error)
		return error;

	return 0;
}

static int cpcap_battery_init_iio(struct cpcap_battery_ddata *ddata)
{
	const char * const names[CPCAP_BATTERY_IIO_NR] = {
		"battdetb", "battp", "chg_isense", "batti",
	};
	int error, i;

	for (i = 0; i < CPCAP_BATTERY_IIO_NR; i++) {
		ddata->channels[i] = devm_iio_channel_get(ddata->dev,
							  names[i]);
		if (IS_ERR(ddata->channels[i])) {
			error = PTR_ERR(ddata->channels[i]);
			goto out_err;
		}

		if (!ddata->channels[i]->indio_dev) {
			error = -ENXIO;
			goto out_err;
		}
	}

	return 0;

out_err:
	dev_err(ddata->dev, "could not initialize VBUS or ID IIO: %i\n",
		error);

	return error;
}

/*
 * Based on the values from Motorola mapphone Linux kernel. In the
 * the Motorola mapphone Linux kernel tree the value for pm_cd_factor
 * is passed to the kernel via device tree. If it turns out to be
 * something device specific we can consider that too later.
 *
 * And looking at the battery full and shutdown values for the stock
 * kernel on droid 4, full is 4351000 and software initiates shutdown
 * at 3078000. The device will die around 2743000.
 */
static const struct cpcap_battery_config cpcap_battery_default_data = {
	.ccm = 0x3ff,
	.cd_factor = 0x3cc,
	.info.technology = POWER_SUPPLY_TECHNOLOGY_LION,
	.info.voltage_max_design = 4351000,
	.info.voltage_min_design = 3100000,
	.info.charge_full_design = 1740000,
};

#ifdef CONFIG_OF
static const struct of_device_id cpcap_battery_id_table[] = {
	{
		.compatible = "motorola,cpcap-battery",
		.data = &cpcap_battery_default_data,
	},
	{},
};
MODULE_DEVICE_TABLE(of, cpcap_battery_id_table);
#endif

static int cpcap_battery_probe(struct platform_device *pdev)
{
	struct power_supply_desc *psy_desc;
	struct cpcap_battery_ddata *ddata;
	const struct of_device_id *match;
	struct power_supply_config psy_cfg = {};
	int error;

	match = of_match_device(of_match_ptr(cpcap_battery_id_table),
				&pdev->dev);
	if (!match)
		return -EINVAL;

	if (!match->data) {
		dev_err(&pdev->dev, "no configuration data found\n");

		return -ENODEV;
	}

	ddata = devm_kzalloc(&pdev->dev, sizeof(*ddata), GFP_KERNEL);
	if (!ddata)
		return -ENOMEM;

	INIT_LIST_HEAD(&ddata->irq_list);
	ddata->dev = &pdev->dev;
	memcpy(&ddata->config, match->data, sizeof(ddata->config));

	ddata->reg = dev_get_regmap(ddata->dev->parent, NULL);
	if (!ddata->reg)
		return -ENODEV;

	error = cpcap_get_vendor(ddata->dev, ddata->reg, &ddata->vendor);
	if (error)
		return error;

	platform_set_drvdata(pdev, ddata);

	error = regmap_update_bits(ddata->reg, CPCAP_REG_CCM,
				   0xffff, ddata->config.ccm);
	if (error)
		return error;

	error = cpcap_battery_init_interrupts(pdev, ddata);
	if (error)
		return error;

	error = cpcap_battery_init_iio(ddata);
	if (error)
		return error;

	psy_desc = devm_kzalloc(ddata->dev, sizeof(*psy_desc), GFP_KERNEL);
	if (!psy_desc)
		return -ENOMEM;

	psy_desc->name = "battery",
	psy_desc->type = POWER_SUPPLY_TYPE_BATTERY,
	psy_desc->properties = cpcap_battery_props,
	psy_desc->num_properties = ARRAY_SIZE(cpcap_battery_props),
	psy_desc->get_property = cpcap_battery_get_property,

	psy_cfg.of_node = pdev->dev.of_node;
	psy_cfg.drv_data = ddata;

	ddata->psy = devm_power_supply_register(ddata->dev, psy_desc,
						&psy_cfg);
	error = PTR_ERR_OR_ZERO(ddata->psy);
	if (error) {
		dev_err(ddata->dev, "failed to register power supply\n");
		return error;
	}

	atomic_set(&ddata->active, 1);

	return 0;
}

static int cpcap_battery_remove(struct platform_device *pdev)
{
	struct cpcap_battery_ddata *ddata = platform_get_drvdata(pdev);
	int error;

	atomic_set(&ddata->active, 0);
	error = regmap_update_bits(ddata->reg, CPCAP_REG_BPEOL,
				   0xffff, 0);
	if (error)
		dev_err(&pdev->dev, "could not disable: %i\n", error);

	return 0;
}

static struct platform_driver cpcap_battery_driver = {
	.driver	= {
		.name		= "cpcap_battery",
		.of_match_table = of_match_ptr(cpcap_battery_id_table),
	},
	.probe	= cpcap_battery_probe,
	.remove = cpcap_battery_remove,
};
module_platform_driver(cpcap_battery_driver);

MODULE_LICENSE("GPL v2");
MODULE_AUTHOR("Tony Lindgren <tony@atomide.com>");
MODULE_DESCRIPTION("CPCAP PMIC Battery Driver");