summaryrefslogtreecommitdiffstats
path: root/drivers/power/ds2781_battery.c
blob: ce1200914b89cd38df541aac9b5321417a3187d9 (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
/*
 * 1-wire client/driver for the Maxim/Dallas DS2781 Stand-Alone Fuel Gauge IC
 *
 * Author: Renata Sayakhova <renata@oktetlabs.ru>
 *
 * Based on ds2780_battery drivers
 *
 * 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/module.h>
#include <linux/slab.h>
#include <linux/param.h>
#include <linux/pm.h>
#include <linux/platform_device.h>
#include <linux/power_supply.h>
#include <linux/idr.h>

#include "../w1/w1.h"
#include "../w1/slaves/w1_ds2781.h"

/* Current unit measurement in uA for a 1 milli-ohm sense resistor */
#define DS2781_CURRENT_UNITS	1563
/* Charge unit measurement in uAh for a 1 milli-ohm sense resistor */
#define DS2781_CHARGE_UNITS		6250
/* Number of bytes in user EEPROM space */
#define DS2781_USER_EEPROM_SIZE		(DS2781_EEPROM_BLOCK0_END - \
					DS2781_EEPROM_BLOCK0_START + 1)
/* Number of bytes in parameter EEPROM space */
#define DS2781_PARAM_EEPROM_SIZE	(DS2781_EEPROM_BLOCK1_END - \
					DS2781_EEPROM_BLOCK1_START + 1)

struct ds2781_device_info {
	struct device *dev;
	struct power_supply bat;
	struct device *w1_dev;
};

enum current_types {
	CURRENT_NOW,
	CURRENT_AVG,
};

static const char model[] = "DS2781";
static const char manufacturer[] = "Maxim/Dallas";

static inline struct ds2781_device_info *
to_ds2781_device_info(struct power_supply *psy)
{
	return container_of(psy, struct ds2781_device_info, bat);
}

static inline struct power_supply *to_power_supply(struct device *dev)
{
	return dev_get_drvdata(dev);
}

static inline int ds2781_battery_io(struct ds2781_device_info *dev_info,
	char *buf, int addr, size_t count, int io)
{
	return w1_ds2781_io(dev_info->w1_dev, buf, addr, count, io);
}

static int w1_ds2781_read(struct ds2781_device_info *dev_info, char *buf,
		int addr, size_t count)
{
	return ds2781_battery_io(dev_info, buf, addr, count, 0);
}

static inline int ds2781_read8(struct ds2781_device_info *dev_info, u8 *val,
	int addr)
{
	return ds2781_battery_io(dev_info, val, addr, sizeof(u8), 0);
}

static int ds2781_read16(struct ds2781_device_info *dev_info, s16 *val,
	int addr)
{
	int ret;
	u8 raw[2];

	ret = ds2781_battery_io(dev_info, raw, addr, sizeof(raw), 0);
	if (ret < 0)
		return ret;

	*val = (raw[0] << 8) | raw[1];

	return 0;
}

static inline int ds2781_read_block(struct ds2781_device_info *dev_info,
	u8 *val, int addr, size_t count)
{
	return ds2781_battery_io(dev_info, val, addr, count, 0);
}

static inline int ds2781_write(struct ds2781_device_info *dev_info, u8 *val,
	int addr, size_t count)
{
	return ds2781_battery_io(dev_info, val, addr, count, 1);
}

static inline int ds2781_store_eeprom(struct device *dev, int addr)
{
	return w1_ds2781_eeprom_cmd(dev, addr, W1_DS2781_COPY_DATA);
}

static inline int ds2781_recall_eeprom(struct device *dev, int addr)
{
	return w1_ds2781_eeprom_cmd(dev, addr, W1_DS2781_RECALL_DATA);
}

static int ds2781_save_eeprom(struct ds2781_device_info *dev_info, int reg)
{
	int ret;

	ret = ds2781_store_eeprom(dev_info->w1_dev, reg);
	if (ret < 0)
		return ret;

	ret = ds2781_recall_eeprom(dev_info->w1_dev, reg);
	if (ret < 0)
		return ret;

	return 0;
}

/* Set sense resistor value in mhos */
static int ds2781_set_sense_register(struct ds2781_device_info *dev_info,
	u8 conductance)
{
	int ret;

	ret = ds2781_write(dev_info, &conductance,
				DS2781_RSNSP, sizeof(u8));
	if (ret < 0)
		return ret;

	return ds2781_save_eeprom(dev_info, DS2781_RSNSP);
}

/* Get RSGAIN value from 0 to 1.999 in steps of 0.001 */
static int ds2781_get_rsgain_register(struct ds2781_device_info *dev_info,
	u16 *rsgain)
{
	return ds2781_read16(dev_info, rsgain, DS2781_RSGAIN_MSB);
}

/* Set RSGAIN value from 0 to 1.999 in steps of 0.001 */
static int ds2781_set_rsgain_register(struct ds2781_device_info *dev_info,
	u16 rsgain)
{
	int ret;
	u8 raw[] = {rsgain >> 8, rsgain & 0xFF};

	ret = ds2781_write(dev_info, raw,
				DS2781_RSGAIN_MSB, sizeof(raw));
	if (ret < 0)
		return ret;

	return ds2781_save_eeprom(dev_info, DS2781_RSGAIN_MSB);
}

static int ds2781_get_voltage(struct ds2781_device_info *dev_info,
	int *voltage_uV)
{
	int ret;
	char val[2];
	int voltage_raw;

	ret = w1_ds2781_read(dev_info, val, DS2781_VOLT_MSB, 2 * sizeof(u8));
	if (ret < 0)
		return ret;
	/*
	 * The voltage value is located in 10 bits across the voltage MSB
	 * and LSB registers in two's compliment form
	 * Sign bit of the voltage value is in bit 7 of the voltage MSB register
	 * Bits 9 - 3 of the voltage value are in bits 6 - 0 of the
	 * voltage MSB register
	 * Bits 2 - 0 of the voltage value are in bits 7 - 5 of the
	 * voltage LSB register
	 */
	voltage_raw = (val[0] << 3) |
		(val[1] >> 5);

	/* DS2781 reports voltage in units of 9.76mV, but the battery class
	 * reports in units of uV, so convert by multiplying by 9760. */
	*voltage_uV = voltage_raw * 9760;

	return 0;
}

static int ds2781_get_temperature(struct ds2781_device_info *dev_info,
	int *temp)
{
	int ret;
	char val[2];
	int temp_raw;

	ret = w1_ds2781_read(dev_info, val, DS2781_TEMP_MSB, 2 * sizeof(u8));
	if (ret < 0)
		return ret;
	/*
	 * The temperature value is located in 10 bits across the temperature
	 * MSB and LSB registers in two's compliment form
	 * Sign bit of the temperature value is in bit 7 of the temperature
	 * MSB register
	 * Bits 9 - 3 of the temperature value are in bits 6 - 0 of the
	 * temperature MSB register
	 * Bits 2 - 0 of the temperature value are in bits 7 - 5 of the
	 * temperature LSB register
	 */
	temp_raw = ((val[0]) << 3) |
		(val[1] >> 5);
	*temp = temp_raw + (temp_raw / 4);

	return 0;
}

static int ds2781_get_current(struct ds2781_device_info *dev_info,
	enum current_types type, int *current_uA)
{
	int ret, sense_res;
	s16 current_raw;
	u8 sense_res_raw, reg_msb;

	/*
	 * The units of measurement for current are dependent on the value of
	 * the sense resistor.
	 */
	ret = ds2781_read8(dev_info, &sense_res_raw, DS2781_RSNSP);
	if (ret < 0)
		return ret;

	if (sense_res_raw == 0) {
		dev_err(dev_info->dev, "sense resistor value is 0\n");
		return -EINVAL;
	}
	sense_res = 1000 / sense_res_raw;

	if (type == CURRENT_NOW)
		reg_msb = DS2781_CURRENT_MSB;
	else if (type == CURRENT_AVG)
		reg_msb = DS2781_IAVG_MSB;
	else
		return -EINVAL;

	/*
	 * The current value is located in 16 bits across the current MSB
	 * and LSB registers in two's compliment form
	 * Sign bit of the current value is in bit 7 of the current MSB register
	 * Bits 14 - 8 of the current value are in bits 6 - 0 of the current
	 * MSB register
	 * Bits 7 - 0 of the current value are in bits 7 - 0 of the current
	 * LSB register
	 */
	ret = ds2781_read16(dev_info, &current_raw, reg_msb);
	if (ret < 0)
		return ret;

	*current_uA = current_raw * (DS2781_CURRENT_UNITS / sense_res);
	return 0;
}

static int ds2781_get_accumulated_current(struct ds2781_device_info *dev_info,
	int *accumulated_current)
{
	int ret, sense_res;
	s16 current_raw;
	u8 sense_res_raw;

	/*
	 * The units of measurement for accumulated current are dependent on
	 * the value of the sense resistor.
	 */
	ret = ds2781_read8(dev_info, &sense_res_raw, DS2781_RSNSP);
	if (ret < 0)
		return ret;

	if (sense_res_raw == 0) {
		dev_err(dev_info->dev, "sense resistor value is 0\n");
		return -EINVAL;
	}
	sense_res = 1000 / sense_res_raw;

	/*
	 * The ACR value is located in 16 bits across the ACR MSB and
	 * LSB registers
	 * Bits 15 - 8 of the ACR value are in bits 7 - 0 of the ACR
	 * MSB register
	 * Bits 7 - 0 of the ACR value are in bits 7 - 0 of the ACR
	 * LSB register
	 */
	ret = ds2781_read16(dev_info, &current_raw, DS2781_ACR_MSB);
	if (ret < 0)
		return ret;

	*accumulated_current = current_raw * (DS2781_CHARGE_UNITS / sense_res);
	return 0;
}

static int ds2781_get_capacity(struct ds2781_device_info *dev_info,
	int *capacity)
{
	int ret;
	u8 raw;

	ret = ds2781_read8(dev_info, &raw, DS2781_RARC);
	if (ret < 0)
		return ret;

	*capacity = raw;
	return 0;
}

static int ds2781_get_status(struct ds2781_device_info *dev_info, int *status)
{
	int ret, current_uA, capacity;

	ret = ds2781_get_current(dev_info, CURRENT_NOW, &current_uA);
	if (ret < 0)
		return ret;

	ret = ds2781_get_capacity(dev_info, &capacity);
	if (ret < 0)
		return ret;

	if (power_supply_am_i_supplied(&dev_info->bat)) {
		if (capacity == 100)
			*status = POWER_SUPPLY_STATUS_FULL;
		else if (current_uA > 50000)
			*status = POWER_SUPPLY_STATUS_CHARGING;
		else
			*status = POWER_SUPPLY_STATUS_NOT_CHARGING;
	} else {
		*status = POWER_SUPPLY_STATUS_DISCHARGING;
	}
	return 0;
}

static int ds2781_get_charge_now(struct ds2781_device_info *dev_info,
	int *charge_now)
{
	int ret;
	u16 charge_raw;

	/*
	 * The RAAC value is located in 16 bits across the RAAC MSB and
	 * LSB registers
	 * Bits 15 - 8 of the RAAC value are in bits 7 - 0 of the RAAC
	 * MSB register
	 * Bits 7 - 0 of the RAAC value are in bits 7 - 0 of the RAAC
	 * LSB register
	 */
	ret = ds2781_read16(dev_info, &charge_raw, DS2781_RAAC_MSB);
	if (ret < 0)
		return ret;

	*charge_now = charge_raw * 1600;
	return 0;
}

static int ds2781_get_control_register(struct ds2781_device_info *dev_info,
	u8 *control_reg)
{
	return ds2781_read8(dev_info, control_reg, DS2781_CONTROL);
}

static int ds2781_set_control_register(struct ds2781_device_info *dev_info,
	u8 control_reg)
{
	int ret;

	ret = ds2781_write(dev_info, &control_reg,
				DS2781_CONTROL, sizeof(u8));
	if (ret < 0)
		return ret;

	return ds2781_save_eeprom(dev_info, DS2781_CONTROL);
}

static int ds2781_battery_get_property(struct power_supply *psy,
	enum power_supply_property psp,
	union power_supply_propval *val)
{
	int ret = 0;
	struct ds2781_device_info *dev_info = to_ds2781_device_info(psy);

	switch (psp) {
	case POWER_SUPPLY_PROP_VOLTAGE_NOW:
		ret = ds2781_get_voltage(dev_info, &val->intval);
		break;

	case POWER_SUPPLY_PROP_TEMP:
		ret = ds2781_get_temperature(dev_info, &val->intval);
		break;

	case POWER_SUPPLY_PROP_MODEL_NAME:
		val->strval = model;
		break;

	case POWER_SUPPLY_PROP_MANUFACTURER:
		val->strval = manufacturer;
		break;

	case POWER_SUPPLY_PROP_CURRENT_NOW:
		ret = ds2781_get_current(dev_info, CURRENT_NOW, &val->intval);
		break;

	case POWER_SUPPLY_PROP_CURRENT_AVG:
		ret = ds2781_get_current(dev_info, CURRENT_AVG, &val->intval);
		break;

	case POWER_SUPPLY_PROP_STATUS:
		ret = ds2781_get_status(dev_info, &val->intval);
		break;

	case POWER_SUPPLY_PROP_CAPACITY:
		ret = ds2781_get_capacity(dev_info, &val->intval);
		break;

	case POWER_SUPPLY_PROP_CHARGE_COUNTER:
		ret = ds2781_get_accumulated_current(dev_info, &val->intval);
		break;

	case POWER_SUPPLY_PROP_CHARGE_NOW:
		ret = ds2781_get_charge_now(dev_info, &val->intval);
		break;

	default:
		ret = -EINVAL;
	}

	return ret;
}

static enum power_supply_property ds2781_battery_props[] = {
	POWER_SUPPLY_PROP_STATUS,
	POWER_SUPPLY_PROP_VOLTAGE_NOW,
	POWER_SUPPLY_PROP_TEMP,
	POWER_SUPPLY_PROP_MODEL_NAME,
	POWER_SUPPLY_PROP_MANUFACTURER,
	POWER_SUPPLY_PROP_CURRENT_NOW,
	POWER_SUPPLY_PROP_CURRENT_AVG,
	POWER_SUPPLY_PROP_CAPACITY,
	POWER_SUPPLY_PROP_CHARGE_COUNTER,
	POWER_SUPPLY_PROP_CHARGE_NOW,
};

static ssize_t ds2781_get_pmod_enabled(struct device *dev,
	struct device_attribute *attr,
	char *buf)
{
	int ret;
	u8 control_reg;
	struct power_supply *psy = to_power_supply(dev);
	struct ds2781_device_info *dev_info = to_ds2781_device_info(psy);

	/* Get power mode */
	ret = ds2781_get_control_register(dev_info, &control_reg);
	if (ret < 0)
		return ret;

	return sprintf(buf, "%d\n",
		 !!(control_reg & DS2781_CONTROL_PMOD));
}

static ssize_t ds2781_set_pmod_enabled(struct device *dev,
	struct device_attribute *attr,
	const char *buf,
	size_t count)
{
	int ret;
	u8 control_reg, new_setting;
	struct power_supply *psy = to_power_supply(dev);
	struct ds2781_device_info *dev_info = to_ds2781_device_info(psy);

	/* Set power mode */
	ret = ds2781_get_control_register(dev_info, &control_reg);
	if (ret < 0)
		return ret;

	ret = kstrtou8(buf, 0, &new_setting);
	if (ret < 0)
		return ret;

	if ((new_setting != 0) && (new_setting != 1)) {
		dev_err(dev_info->dev, "Invalid pmod setting (0 or 1)\n");
		return -EINVAL;
	}

	if (new_setting)
		control_reg |= DS2781_CONTROL_PMOD;
	else
		control_reg &= ~DS2781_CONTROL_PMOD;

	ret = ds2781_set_control_register(dev_info, control_reg);
	if (ret < 0)
		return ret;

	return count;
}

static ssize_t ds2781_get_sense_resistor_value(struct device *dev,
	struct device_attribute *attr,
	char *buf)
{
	int ret;
	u8 sense_resistor;
	struct power_supply *psy = to_power_supply(dev);
	struct ds2781_device_info *dev_info = to_ds2781_device_info(psy);

	ret = ds2781_read8(dev_info, &sense_resistor, DS2781_RSNSP);
	if (ret < 0)
		return ret;

	ret = sprintf(buf, "%d\n", sense_resistor);
	return ret;
}

static ssize_t ds2781_set_sense_resistor_value(struct device *dev,
	struct device_attribute *attr,
	const char *buf,
	size_t count)
{
	int ret;
	u8 new_setting;
	struct power_supply *psy = to_power_supply(dev);
	struct ds2781_device_info *dev_info = to_ds2781_device_info(psy);

	ret = kstrtou8(buf, 0, &new_setting);
	if (ret < 0)
		return ret;

	ret = ds2781_set_sense_register(dev_info, new_setting);
	if (ret < 0)
		return ret;

	return count;
}

static ssize_t ds2781_get_rsgain_setting(struct device *dev,
	struct device_attribute *attr,
	char *buf)
{
	int ret;
	u16 rsgain;
	struct power_supply *psy = to_power_supply(dev);
	struct ds2781_device_info *dev_info = to_ds2781_device_info(psy);

	ret = ds2781_get_rsgain_register(dev_info, &rsgain);
	if (ret < 0)
		return ret;

	return sprintf(buf, "%d\n", rsgain);
}

static ssize_t ds2781_set_rsgain_setting(struct device *dev,
	struct device_attribute *attr,
	const char *buf,
	size_t count)
{
	int ret;
	u16 new_setting;
	struct power_supply *psy = to_power_supply(dev);
	struct ds2781_device_info *dev_info = to_ds2781_device_info(psy);

	ret = kstrtou16(buf, 0, &new_setting);
	if (ret < 0)
		return ret;

	/* Gain can only be from 0 to 1.999 in steps of .001 */
	if (new_setting > 1999) {
		dev_err(dev_info->dev, "Invalid rsgain setting (0 - 1999)\n");
		return -EINVAL;
	}

	ret = ds2781_set_rsgain_register(dev_info, new_setting);
	if (ret < 0)
		return ret;

	return count;
}

static ssize_t ds2781_get_pio_pin(struct device *dev,
	struct device_attribute *attr,
	char *buf)
{
	int ret;
	u8 sfr;
	struct power_supply *psy = to_power_supply(dev);
	struct ds2781_device_info *dev_info = to_ds2781_device_info(psy);

	ret = ds2781_read8(dev_info, &sfr, DS2781_SFR);
	if (ret < 0)
		return ret;

	ret = sprintf(buf, "%d\n", sfr & DS2781_SFR_PIOSC);
	return ret;
}

static ssize_t ds2781_set_pio_pin(struct device *dev,
	struct device_attribute *attr,
	const char *buf,
	size_t count)
{
	int ret;
	u8 new_setting;
	struct power_supply *psy = to_power_supply(dev);
	struct ds2781_device_info *dev_info = to_ds2781_device_info(psy);

	ret = kstrtou8(buf, 0, &new_setting);
	if (ret < 0)
		return ret;

	if ((new_setting != 0) && (new_setting != 1)) {
		dev_err(dev_info->dev, "Invalid pio_pin setting (0 or 1)\n");
		return -EINVAL;
	}

	ret = ds2781_write(dev_info, &new_setting,
				DS2781_SFR, sizeof(u8));
	if (ret < 0)
		return ret;

	return count;
}

static ssize_t ds2781_read_param_eeprom_bin(struct file *filp,
				struct kobject *kobj,
				struct bin_attribute *bin_attr,
				char *buf, loff_t off, size_t count)
{
	struct device *dev = container_of(kobj, struct device, kobj);
	struct power_supply *psy = to_power_supply(dev);
	struct ds2781_device_info *dev_info = to_ds2781_device_info(psy);

	count = min_t(loff_t, count, DS2781_PARAM_EEPROM_SIZE - off);

	return ds2781_read_block(dev_info, buf,
				DS2781_EEPROM_BLOCK1_START + off, count);
}

static ssize_t ds2781_write_param_eeprom_bin(struct file *filp,
				struct kobject *kobj,
				struct bin_attribute *bin_attr,
				char *buf, loff_t off, size_t count)
{
	struct device *dev = container_of(kobj, struct device, kobj);
	struct power_supply *psy = to_power_supply(dev);
	struct ds2781_device_info *dev_info = to_ds2781_device_info(psy);
	int ret;

	count = min_t(loff_t, count, DS2781_PARAM_EEPROM_SIZE - off);

	ret = ds2781_write(dev_info, buf,
				DS2781_EEPROM_BLOCK1_START + off, count);
	if (ret < 0)
		return ret;

	ret = ds2781_save_eeprom(dev_info, DS2781_EEPROM_BLOCK1_START);
	if (ret < 0)
		return ret;

	return count;
}

static struct bin_attribute ds2781_param_eeprom_bin_attr = {
	.attr = {
		.name = "param_eeprom",
		.mode = S_IRUGO | S_IWUSR,
	},
	.size = DS2781_PARAM_EEPROM_SIZE,
	.read = ds2781_read_param_eeprom_bin,
	.write = ds2781_write_param_eeprom_bin,
};

static ssize_t ds2781_read_user_eeprom_bin(struct file *filp,
				struct kobject *kobj,
				struct bin_attribute *bin_attr,
				char *buf, loff_t off, size_t count)
{
	struct device *dev = container_of(kobj, struct device, kobj);
	struct power_supply *psy = to_power_supply(dev);
	struct ds2781_device_info *dev_info = to_ds2781_device_info(psy);

	count = min_t(loff_t, count, DS2781_USER_EEPROM_SIZE - off);

	return ds2781_read_block(dev_info, buf,
				DS2781_EEPROM_BLOCK0_START + off, count);

}

static ssize_t ds2781_write_user_eeprom_bin(struct file *filp,
				struct kobject *kobj,
				struct bin_attribute *bin_attr,
				char *buf, loff_t off, size_t count)
{
	struct device *dev = container_of(kobj, struct device, kobj);
	struct power_supply *psy = to_power_supply(dev);
	struct ds2781_device_info *dev_info = to_ds2781_device_info(psy);
	int ret;

	count = min_t(loff_t, count, DS2781_USER_EEPROM_SIZE - off);

	ret = ds2781_write(dev_info, buf,
				DS2781_EEPROM_BLOCK0_START + off, count);
	if (ret < 0)
		return ret;

	ret = ds2781_save_eeprom(dev_info, DS2781_EEPROM_BLOCK0_START);
	if (ret < 0)
		return ret;

	return count;
}

static struct bin_attribute ds2781_user_eeprom_bin_attr = {
	.attr = {
		.name = "user_eeprom",
		.mode = S_IRUGO | S_IWUSR,
	},
	.size = DS2781_USER_EEPROM_SIZE,
	.read = ds2781_read_user_eeprom_bin,
	.write = ds2781_write_user_eeprom_bin,
};

static DEVICE_ATTR(pmod_enabled, S_IRUGO | S_IWUSR, ds2781_get_pmod_enabled,
	ds2781_set_pmod_enabled);
static DEVICE_ATTR(sense_resistor_value, S_IRUGO | S_IWUSR,
	ds2781_get_sense_resistor_value, ds2781_set_sense_resistor_value);
static DEVICE_ATTR(rsgain_setting, S_IRUGO | S_IWUSR, ds2781_get_rsgain_setting,
	ds2781_set_rsgain_setting);
static DEVICE_ATTR(pio_pin, S_IRUGO | S_IWUSR, ds2781_get_pio_pin,
	ds2781_set_pio_pin);


static struct attribute *ds2781_attributes[] = {
	&dev_attr_pmod_enabled.attr,
	&dev_attr_sense_resistor_value.attr,
	&dev_attr_rsgain_setting.attr,
	&dev_attr_pio_pin.attr,
	NULL
};

static const struct attribute_group ds2781_attr_group = {
	.attrs = ds2781_attributes,
};

static int __devinit ds2781_battery_probe(struct platform_device *pdev)
{
	int ret = 0;
	struct ds2781_device_info *dev_info;

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

	platform_set_drvdata(pdev, dev_info);

	dev_info->dev			= &pdev->dev;
	dev_info->w1_dev		= pdev->dev.parent;
	dev_info->bat.name		= dev_name(&pdev->dev);
	dev_info->bat.type		= POWER_SUPPLY_TYPE_BATTERY;
	dev_info->bat.properties	= ds2781_battery_props;
	dev_info->bat.num_properties	= ARRAY_SIZE(ds2781_battery_props);
	dev_info->bat.get_property	= ds2781_battery_get_property;

	ret = power_supply_register(&pdev->dev, &dev_info->bat);
	if (ret) {
		dev_err(dev_info->dev, "failed to register battery\n");
		goto fail;
	}

	ret = sysfs_create_group(&dev_info->bat.dev->kobj, &ds2781_attr_group);
	if (ret) {
		dev_err(dev_info->dev, "failed to create sysfs group\n");
		goto fail_unregister;
	}

	ret = sysfs_create_bin_file(&dev_info->bat.dev->kobj,
					&ds2781_param_eeprom_bin_attr);
	if (ret) {
		dev_err(dev_info->dev,
				"failed to create param eeprom bin file");
		goto fail_remove_group;
	}

	ret = sysfs_create_bin_file(&dev_info->bat.dev->kobj,
					&ds2781_user_eeprom_bin_attr);
	if (ret) {
		dev_err(dev_info->dev,
				"failed to create user eeprom bin file");
		goto fail_remove_bin_file;
	}

	return 0;

fail_remove_bin_file:
	sysfs_remove_bin_file(&dev_info->bat.dev->kobj,
				&ds2781_param_eeprom_bin_attr);
fail_remove_group:
	sysfs_remove_group(&dev_info->bat.dev->kobj, &ds2781_attr_group);
fail_unregister:
	power_supply_unregister(&dev_info->bat);
fail:
	return ret;
}

static int __devexit ds2781_battery_remove(struct platform_device *pdev)
{
	struct ds2781_device_info *dev_info = platform_get_drvdata(pdev);

	/* remove attributes */
	sysfs_remove_group(&dev_info->bat.dev->kobj, &ds2781_attr_group);

	power_supply_unregister(&dev_info->bat);

	return 0;
}

static struct platform_driver ds2781_battery_driver = {
	.driver = {
		.name = "ds2781-battery",
	},
	.probe	  = ds2781_battery_probe,
	.remove   = ds2781_battery_remove,
};
module_platform_driver(ds2781_battery_driver);

MODULE_LICENSE("GPL");
MODULE_AUTHOR("Renata Sayakhova <renata@oktetlabs.ru>");
MODULE_DESCRIPTION("Maxim/Dallas DS2781 Stand-Alone Fuel Gauage IC driver");
MODULE_ALIAS("platform:ds2781-battery");

OpenPOWER on IntegriCloud