1/*
2 * 1-wire client/driver for the Maxim/Dallas DS2781 Stand-Alone Fuel Gauge IC
3 *
4 * Author: Renata Sayakhova <renata@oktetlabs.ru>
5 *
6 * Based on ds2780_battery drivers
7 *
8 * This program is free software; you can redistribute it and/or modify
9 * it under the terms of the GNU General Public License version 2 as
10 * published by the Free Software Foundation.
11 *
12 */
13
14#include <linux/module.h>
15#include <linux/slab.h>
16#include <linux/param.h>
17#include <linux/pm.h>
18#include <linux/platform_device.h>
19#include <linux/power_supply.h>
20#include <linux/idr.h>
21
22#include "../w1/w1.h"
23#include "../w1/slaves/w1_ds2781.h"
24
25/* Current unit measurement in uA for a 1 milli-ohm sense resistor */
26#define DS2781_CURRENT_UNITS	1563
27/* Charge unit measurement in uAh for a 1 milli-ohm sense resistor */
28#define DS2781_CHARGE_UNITS		6250
29/* Number of bytes in user EEPROM space */
30#define DS2781_USER_EEPROM_SIZE		(DS2781_EEPROM_BLOCK0_END - \
31					DS2781_EEPROM_BLOCK0_START + 1)
32/* Number of bytes in parameter EEPROM space */
33#define DS2781_PARAM_EEPROM_SIZE	(DS2781_EEPROM_BLOCK1_END - \
34					DS2781_EEPROM_BLOCK1_START + 1)
35
36struct ds2781_device_info {
37	struct device *dev;
38	struct power_supply *bat;
39	struct power_supply_desc bat_desc;
40	struct device *w1_dev;
41};
42
43enum current_types {
44	CURRENT_NOW,
45	CURRENT_AVG,
46};
47
48static const char model[] = "DS2781";
49static const char manufacturer[] = "Maxim/Dallas";
50
51static inline struct ds2781_device_info *
52to_ds2781_device_info(struct power_supply *psy)
53{
54	return power_supply_get_drvdata(psy);
55}
56
57static inline struct power_supply *to_power_supply(struct device *dev)
58{
59	return dev_get_drvdata(dev);
60}
61
62static inline int ds2781_battery_io(struct ds2781_device_info *dev_info,
63	char *buf, int addr, size_t count, int io)
64{
65	return w1_ds2781_io(dev_info->w1_dev, buf, addr, count, io);
66}
67
68static int w1_ds2781_read(struct ds2781_device_info *dev_info, char *buf,
69		int addr, size_t count)
70{
71	return ds2781_battery_io(dev_info, buf, addr, count, 0);
72}
73
74static inline int ds2781_read8(struct ds2781_device_info *dev_info, u8 *val,
75	int addr)
76{
77	return ds2781_battery_io(dev_info, val, addr, sizeof(u8), 0);
78}
79
80static int ds2781_read16(struct ds2781_device_info *dev_info, s16 *val,
81	int addr)
82{
83	int ret;
84	u8 raw[2];
85
86	ret = ds2781_battery_io(dev_info, raw, addr, sizeof(raw), 0);
87	if (ret < 0)
88		return ret;
89
90	*val = (raw[0] << 8) | raw[1];
91
92	return 0;
93}
94
95static inline int ds2781_read_block(struct ds2781_device_info *dev_info,
96	u8 *val, int addr, size_t count)
97{
98	return ds2781_battery_io(dev_info, val, addr, count, 0);
99}
100
101static inline int ds2781_write(struct ds2781_device_info *dev_info, u8 *val,
102	int addr, size_t count)
103{
104	return ds2781_battery_io(dev_info, val, addr, count, 1);
105}
106
107static inline int ds2781_store_eeprom(struct device *dev, int addr)
108{
109	return w1_ds2781_eeprom_cmd(dev, addr, W1_DS2781_COPY_DATA);
110}
111
112static inline int ds2781_recall_eeprom(struct device *dev, int addr)
113{
114	return w1_ds2781_eeprom_cmd(dev, addr, W1_DS2781_RECALL_DATA);
115}
116
117static int ds2781_save_eeprom(struct ds2781_device_info *dev_info, int reg)
118{
119	int ret;
120
121	ret = ds2781_store_eeprom(dev_info->w1_dev, reg);
122	if (ret < 0)
123		return ret;
124
125	ret = ds2781_recall_eeprom(dev_info->w1_dev, reg);
126	if (ret < 0)
127		return ret;
128
129	return 0;
130}
131
132/* Set sense resistor value in mhos */
133static int ds2781_set_sense_register(struct ds2781_device_info *dev_info,
134	u8 conductance)
135{
136	int ret;
137
138	ret = ds2781_write(dev_info, &conductance,
139				DS2781_RSNSP, sizeof(u8));
140	if (ret < 0)
141		return ret;
142
143	return ds2781_save_eeprom(dev_info, DS2781_RSNSP);
144}
145
146/* Get RSGAIN value from 0 to 1.999 in steps of 0.001 */
147static int ds2781_get_rsgain_register(struct ds2781_device_info *dev_info,
148	u16 *rsgain)
149{
150	return ds2781_read16(dev_info, rsgain, DS2781_RSGAIN_MSB);
151}
152
153/* Set RSGAIN value from 0 to 1.999 in steps of 0.001 */
154static int ds2781_set_rsgain_register(struct ds2781_device_info *dev_info,
155	u16 rsgain)
156{
157	int ret;
158	u8 raw[] = {rsgain >> 8, rsgain & 0xFF};
159
160	ret = ds2781_write(dev_info, raw,
161				DS2781_RSGAIN_MSB, sizeof(raw));
162	if (ret < 0)
163		return ret;
164
165	return ds2781_save_eeprom(dev_info, DS2781_RSGAIN_MSB);
166}
167
168static int ds2781_get_voltage(struct ds2781_device_info *dev_info,
169	int *voltage_uV)
170{
171	int ret;
172	char val[2];
173	int voltage_raw;
174
175	ret = w1_ds2781_read(dev_info, val, DS2781_VOLT_MSB, 2 * sizeof(u8));
176	if (ret < 0)
177		return ret;
178	/*
179	 * The voltage value is located in 10 bits across the voltage MSB
180	 * and LSB registers in two's compliment form
181	 * Sign bit of the voltage value is in bit 7 of the voltage MSB register
182	 * Bits 9 - 3 of the voltage value are in bits 6 - 0 of the
183	 * voltage MSB register
184	 * Bits 2 - 0 of the voltage value are in bits 7 - 5 of the
185	 * voltage LSB register
186	 */
187	voltage_raw = (val[0] << 3) |
188		(val[1] >> 5);
189
190	/* DS2781 reports voltage in units of 9.76mV, but the battery class
191	 * reports in units of uV, so convert by multiplying by 9760. */
192	*voltage_uV = voltage_raw * 9760;
193
194	return 0;
195}
196
197static int ds2781_get_temperature(struct ds2781_device_info *dev_info,
198	int *temp)
199{
200	int ret;
201	char val[2];
202	int temp_raw;
203
204	ret = w1_ds2781_read(dev_info, val, DS2781_TEMP_MSB, 2 * sizeof(u8));
205	if (ret < 0)
206		return ret;
207	/*
208	 * The temperature value is located in 10 bits across the temperature
209	 * MSB and LSB registers in two's compliment form
210	 * Sign bit of the temperature value is in bit 7 of the temperature
211	 * MSB register
212	 * Bits 9 - 3 of the temperature value are in bits 6 - 0 of the
213	 * temperature MSB register
214	 * Bits 2 - 0 of the temperature value are in bits 7 - 5 of the
215	 * temperature LSB register
216	 */
217	temp_raw = ((val[0]) << 3) |
218		(val[1] >> 5);
219	*temp = temp_raw + (temp_raw / 4);
220
221	return 0;
222}
223
224static int ds2781_get_current(struct ds2781_device_info *dev_info,
225	enum current_types type, int *current_uA)
226{
227	int ret, sense_res;
228	s16 current_raw;
229	u8 sense_res_raw, reg_msb;
230
231	/*
232	 * The units of measurement for current are dependent on the value of
233	 * the sense resistor.
234	 */
235	ret = ds2781_read8(dev_info, &sense_res_raw, DS2781_RSNSP);
236	if (ret < 0)
237		return ret;
238
239	if (sense_res_raw == 0) {
240		dev_err(dev_info->dev, "sense resistor value is 0\n");
241		return -EINVAL;
242	}
243	sense_res = 1000 / sense_res_raw;
244
245	if (type == CURRENT_NOW)
246		reg_msb = DS2781_CURRENT_MSB;
247	else if (type == CURRENT_AVG)
248		reg_msb = DS2781_IAVG_MSB;
249	else
250		return -EINVAL;
251
252	/*
253	 * The current value is located in 16 bits across the current MSB
254	 * and LSB registers in two's compliment form
255	 * Sign bit of the current value is in bit 7 of the current MSB register
256	 * Bits 14 - 8 of the current value are in bits 6 - 0 of the current
257	 * MSB register
258	 * Bits 7 - 0 of the current value are in bits 7 - 0 of the current
259	 * LSB register
260	 */
261	ret = ds2781_read16(dev_info, &current_raw, reg_msb);
262	if (ret < 0)
263		return ret;
264
265	*current_uA = current_raw * (DS2781_CURRENT_UNITS / sense_res);
266	return 0;
267}
268
269static int ds2781_get_accumulated_current(struct ds2781_device_info *dev_info,
270	int *accumulated_current)
271{
272	int ret, sense_res;
273	s16 current_raw;
274	u8 sense_res_raw;
275
276	/*
277	 * The units of measurement for accumulated current are dependent on
278	 * the value of the sense resistor.
279	 */
280	ret = ds2781_read8(dev_info, &sense_res_raw, DS2781_RSNSP);
281	if (ret < 0)
282		return ret;
283
284	if (sense_res_raw == 0) {
285		dev_err(dev_info->dev, "sense resistor value is 0\n");
286		return -EINVAL;
287	}
288	sense_res = 1000 / sense_res_raw;
289
290	/*
291	 * The ACR value is located in 16 bits across the ACR MSB and
292	 * LSB registers
293	 * Bits 15 - 8 of the ACR value are in bits 7 - 0 of the ACR
294	 * MSB register
295	 * Bits 7 - 0 of the ACR value are in bits 7 - 0 of the ACR
296	 * LSB register
297	 */
298	ret = ds2781_read16(dev_info, &current_raw, DS2781_ACR_MSB);
299	if (ret < 0)
300		return ret;
301
302	*accumulated_current = current_raw * (DS2781_CHARGE_UNITS / sense_res);
303	return 0;
304}
305
306static int ds2781_get_capacity(struct ds2781_device_info *dev_info,
307	int *capacity)
308{
309	int ret;
310	u8 raw;
311
312	ret = ds2781_read8(dev_info, &raw, DS2781_RARC);
313	if (ret < 0)
314		return ret;
315
316	*capacity = raw;
317	return 0;
318}
319
320static int ds2781_get_status(struct ds2781_device_info *dev_info, int *status)
321{
322	int ret, current_uA, capacity;
323
324	ret = ds2781_get_current(dev_info, CURRENT_NOW, &current_uA);
325	if (ret < 0)
326		return ret;
327
328	ret = ds2781_get_capacity(dev_info, &capacity);
329	if (ret < 0)
330		return ret;
331
332	if (power_supply_am_i_supplied(dev_info->bat)) {
333		if (capacity == 100)
334			*status = POWER_SUPPLY_STATUS_FULL;
335		else if (current_uA > 50000)
336			*status = POWER_SUPPLY_STATUS_CHARGING;
337		else
338			*status = POWER_SUPPLY_STATUS_NOT_CHARGING;
339	} else {
340		*status = POWER_SUPPLY_STATUS_DISCHARGING;
341	}
342	return 0;
343}
344
345static int ds2781_get_charge_now(struct ds2781_device_info *dev_info,
346	int *charge_now)
347{
348	int ret;
349	u16 charge_raw;
350
351	/*
352	 * The RAAC value is located in 16 bits across the RAAC MSB and
353	 * LSB registers
354	 * Bits 15 - 8 of the RAAC value are in bits 7 - 0 of the RAAC
355	 * MSB register
356	 * Bits 7 - 0 of the RAAC value are in bits 7 - 0 of the RAAC
357	 * LSB register
358	 */
359	ret = ds2781_read16(dev_info, &charge_raw, DS2781_RAAC_MSB);
360	if (ret < 0)
361		return ret;
362
363	*charge_now = charge_raw * 1600;
364	return 0;
365}
366
367static int ds2781_get_control_register(struct ds2781_device_info *dev_info,
368	u8 *control_reg)
369{
370	return ds2781_read8(dev_info, control_reg, DS2781_CONTROL);
371}
372
373static int ds2781_set_control_register(struct ds2781_device_info *dev_info,
374	u8 control_reg)
375{
376	int ret;
377
378	ret = ds2781_write(dev_info, &control_reg,
379				DS2781_CONTROL, sizeof(u8));
380	if (ret < 0)
381		return ret;
382
383	return ds2781_save_eeprom(dev_info, DS2781_CONTROL);
384}
385
386static int ds2781_battery_get_property(struct power_supply *psy,
387	enum power_supply_property psp,
388	union power_supply_propval *val)
389{
390	int ret = 0;
391	struct ds2781_device_info *dev_info = to_ds2781_device_info(psy);
392
393	switch (psp) {
394	case POWER_SUPPLY_PROP_VOLTAGE_NOW:
395		ret = ds2781_get_voltage(dev_info, &val->intval);
396		break;
397
398	case POWER_SUPPLY_PROP_TEMP:
399		ret = ds2781_get_temperature(dev_info, &val->intval);
400		break;
401
402	case POWER_SUPPLY_PROP_MODEL_NAME:
403		val->strval = model;
404		break;
405
406	case POWER_SUPPLY_PROP_MANUFACTURER:
407		val->strval = manufacturer;
408		break;
409
410	case POWER_SUPPLY_PROP_CURRENT_NOW:
411		ret = ds2781_get_current(dev_info, CURRENT_NOW, &val->intval);
412		break;
413
414	case POWER_SUPPLY_PROP_CURRENT_AVG:
415		ret = ds2781_get_current(dev_info, CURRENT_AVG, &val->intval);
416		break;
417
418	case POWER_SUPPLY_PROP_STATUS:
419		ret = ds2781_get_status(dev_info, &val->intval);
420		break;
421
422	case POWER_SUPPLY_PROP_CAPACITY:
423		ret = ds2781_get_capacity(dev_info, &val->intval);
424		break;
425
426	case POWER_SUPPLY_PROP_CHARGE_COUNTER:
427		ret = ds2781_get_accumulated_current(dev_info, &val->intval);
428		break;
429
430	case POWER_SUPPLY_PROP_CHARGE_NOW:
431		ret = ds2781_get_charge_now(dev_info, &val->intval);
432		break;
433
434	default:
435		ret = -EINVAL;
436	}
437
438	return ret;
439}
440
441static enum power_supply_property ds2781_battery_props[] = {
442	POWER_SUPPLY_PROP_STATUS,
443	POWER_SUPPLY_PROP_VOLTAGE_NOW,
444	POWER_SUPPLY_PROP_TEMP,
445	POWER_SUPPLY_PROP_MODEL_NAME,
446	POWER_SUPPLY_PROP_MANUFACTURER,
447	POWER_SUPPLY_PROP_CURRENT_NOW,
448	POWER_SUPPLY_PROP_CURRENT_AVG,
449	POWER_SUPPLY_PROP_CAPACITY,
450	POWER_SUPPLY_PROP_CHARGE_COUNTER,
451	POWER_SUPPLY_PROP_CHARGE_NOW,
452};
453
454static ssize_t ds2781_get_pmod_enabled(struct device *dev,
455	struct device_attribute *attr,
456	char *buf)
457{
458	int ret;
459	u8 control_reg;
460	struct power_supply *psy = to_power_supply(dev);
461	struct ds2781_device_info *dev_info = to_ds2781_device_info(psy);
462
463	/* Get power mode */
464	ret = ds2781_get_control_register(dev_info, &control_reg);
465	if (ret < 0)
466		return ret;
467
468	return sprintf(buf, "%d\n",
469		 !!(control_reg & DS2781_CONTROL_PMOD));
470}
471
472static ssize_t ds2781_set_pmod_enabled(struct device *dev,
473	struct device_attribute *attr,
474	const char *buf,
475	size_t count)
476{
477	int ret;
478	u8 control_reg, new_setting;
479	struct power_supply *psy = to_power_supply(dev);
480	struct ds2781_device_info *dev_info = to_ds2781_device_info(psy);
481
482	/* Set power mode */
483	ret = ds2781_get_control_register(dev_info, &control_reg);
484	if (ret < 0)
485		return ret;
486
487	ret = kstrtou8(buf, 0, &new_setting);
488	if (ret < 0)
489		return ret;
490
491	if ((new_setting != 0) && (new_setting != 1)) {
492		dev_err(dev_info->dev, "Invalid pmod setting (0 or 1)\n");
493		return -EINVAL;
494	}
495
496	if (new_setting)
497		control_reg |= DS2781_CONTROL_PMOD;
498	else
499		control_reg &= ~DS2781_CONTROL_PMOD;
500
501	ret = ds2781_set_control_register(dev_info, control_reg);
502	if (ret < 0)
503		return ret;
504
505	return count;
506}
507
508static ssize_t ds2781_get_sense_resistor_value(struct device *dev,
509	struct device_attribute *attr,
510	char *buf)
511{
512	int ret;
513	u8 sense_resistor;
514	struct power_supply *psy = to_power_supply(dev);
515	struct ds2781_device_info *dev_info = to_ds2781_device_info(psy);
516
517	ret = ds2781_read8(dev_info, &sense_resistor, DS2781_RSNSP);
518	if (ret < 0)
519		return ret;
520
521	ret = sprintf(buf, "%d\n", sense_resistor);
522	return ret;
523}
524
525static ssize_t ds2781_set_sense_resistor_value(struct device *dev,
526	struct device_attribute *attr,
527	const char *buf,
528	size_t count)
529{
530	int ret;
531	u8 new_setting;
532	struct power_supply *psy = to_power_supply(dev);
533	struct ds2781_device_info *dev_info = to_ds2781_device_info(psy);
534
535	ret = kstrtou8(buf, 0, &new_setting);
536	if (ret < 0)
537		return ret;
538
539	ret = ds2781_set_sense_register(dev_info, new_setting);
540	if (ret < 0)
541		return ret;
542
543	return count;
544}
545
546static ssize_t ds2781_get_rsgain_setting(struct device *dev,
547	struct device_attribute *attr,
548	char *buf)
549{
550	int ret;
551	u16 rsgain;
552	struct power_supply *psy = to_power_supply(dev);
553	struct ds2781_device_info *dev_info = to_ds2781_device_info(psy);
554
555	ret = ds2781_get_rsgain_register(dev_info, &rsgain);
556	if (ret < 0)
557		return ret;
558
559	return sprintf(buf, "%d\n", rsgain);
560}
561
562static ssize_t ds2781_set_rsgain_setting(struct device *dev,
563	struct device_attribute *attr,
564	const char *buf,
565	size_t count)
566{
567	int ret;
568	u16 new_setting;
569	struct power_supply *psy = to_power_supply(dev);
570	struct ds2781_device_info *dev_info = to_ds2781_device_info(psy);
571
572	ret = kstrtou16(buf, 0, &new_setting);
573	if (ret < 0)
574		return ret;
575
576	/* Gain can only be from 0 to 1.999 in steps of .001 */
577	if (new_setting > 1999) {
578		dev_err(dev_info->dev, "Invalid rsgain setting (0 - 1999)\n");
579		return -EINVAL;
580	}
581
582	ret = ds2781_set_rsgain_register(dev_info, new_setting);
583	if (ret < 0)
584		return ret;
585
586	return count;
587}
588
589static ssize_t ds2781_get_pio_pin(struct device *dev,
590	struct device_attribute *attr,
591	char *buf)
592{
593	int ret;
594	u8 sfr;
595	struct power_supply *psy = to_power_supply(dev);
596	struct ds2781_device_info *dev_info = to_ds2781_device_info(psy);
597
598	ret = ds2781_read8(dev_info, &sfr, DS2781_SFR);
599	if (ret < 0)
600		return ret;
601
602	ret = sprintf(buf, "%d\n", sfr & DS2781_SFR_PIOSC);
603	return ret;
604}
605
606static ssize_t ds2781_set_pio_pin(struct device *dev,
607	struct device_attribute *attr,
608	const char *buf,
609	size_t count)
610{
611	int ret;
612	u8 new_setting;
613	struct power_supply *psy = to_power_supply(dev);
614	struct ds2781_device_info *dev_info = to_ds2781_device_info(psy);
615
616	ret = kstrtou8(buf, 0, &new_setting);
617	if (ret < 0)
618		return ret;
619
620	if ((new_setting != 0) && (new_setting != 1)) {
621		dev_err(dev_info->dev, "Invalid pio_pin setting (0 or 1)\n");
622		return -EINVAL;
623	}
624
625	ret = ds2781_write(dev_info, &new_setting,
626				DS2781_SFR, sizeof(u8));
627	if (ret < 0)
628		return ret;
629
630	return count;
631}
632
633static ssize_t ds2781_read_param_eeprom_bin(struct file *filp,
634				struct kobject *kobj,
635				struct bin_attribute *bin_attr,
636				char *buf, loff_t off, size_t count)
637{
638	struct device *dev = container_of(kobj, struct device, kobj);
639	struct power_supply *psy = to_power_supply(dev);
640	struct ds2781_device_info *dev_info = to_ds2781_device_info(psy);
641
642	count = min_t(loff_t, count, DS2781_PARAM_EEPROM_SIZE - off);
643
644	return ds2781_read_block(dev_info, buf,
645				DS2781_EEPROM_BLOCK1_START + off, count);
646}
647
648static ssize_t ds2781_write_param_eeprom_bin(struct file *filp,
649				struct kobject *kobj,
650				struct bin_attribute *bin_attr,
651				char *buf, loff_t off, size_t count)
652{
653	struct device *dev = container_of(kobj, struct device, kobj);
654	struct power_supply *psy = to_power_supply(dev);
655	struct ds2781_device_info *dev_info = to_ds2781_device_info(psy);
656	int ret;
657
658	count = min_t(loff_t, count, DS2781_PARAM_EEPROM_SIZE - off);
659
660	ret = ds2781_write(dev_info, buf,
661				DS2781_EEPROM_BLOCK1_START + off, count);
662	if (ret < 0)
663		return ret;
664
665	ret = ds2781_save_eeprom(dev_info, DS2781_EEPROM_BLOCK1_START);
666	if (ret < 0)
667		return ret;
668
669	return count;
670}
671
672static struct bin_attribute ds2781_param_eeprom_bin_attr = {
673	.attr = {
674		.name = "param_eeprom",
675		.mode = S_IRUGO | S_IWUSR,
676	},
677	.size = DS2781_PARAM_EEPROM_SIZE,
678	.read = ds2781_read_param_eeprom_bin,
679	.write = ds2781_write_param_eeprom_bin,
680};
681
682static ssize_t ds2781_read_user_eeprom_bin(struct file *filp,
683				struct kobject *kobj,
684				struct bin_attribute *bin_attr,
685				char *buf, loff_t off, size_t count)
686{
687	struct device *dev = container_of(kobj, struct device, kobj);
688	struct power_supply *psy = to_power_supply(dev);
689	struct ds2781_device_info *dev_info = to_ds2781_device_info(psy);
690
691	count = min_t(loff_t, count, DS2781_USER_EEPROM_SIZE - off);
692
693	return ds2781_read_block(dev_info, buf,
694				DS2781_EEPROM_BLOCK0_START + off, count);
695
696}
697
698static ssize_t ds2781_write_user_eeprom_bin(struct file *filp,
699				struct kobject *kobj,
700				struct bin_attribute *bin_attr,
701				char *buf, loff_t off, size_t count)
702{
703	struct device *dev = container_of(kobj, struct device, kobj);
704	struct power_supply *psy = to_power_supply(dev);
705	struct ds2781_device_info *dev_info = to_ds2781_device_info(psy);
706	int ret;
707
708	count = min_t(loff_t, count, DS2781_USER_EEPROM_SIZE - off);
709
710	ret = ds2781_write(dev_info, buf,
711				DS2781_EEPROM_BLOCK0_START + off, count);
712	if (ret < 0)
713		return ret;
714
715	ret = ds2781_save_eeprom(dev_info, DS2781_EEPROM_BLOCK0_START);
716	if (ret < 0)
717		return ret;
718
719	return count;
720}
721
722static struct bin_attribute ds2781_user_eeprom_bin_attr = {
723	.attr = {
724		.name = "user_eeprom",
725		.mode = S_IRUGO | S_IWUSR,
726	},
727	.size = DS2781_USER_EEPROM_SIZE,
728	.read = ds2781_read_user_eeprom_bin,
729	.write = ds2781_write_user_eeprom_bin,
730};
731
732static DEVICE_ATTR(pmod_enabled, S_IRUGO | S_IWUSR, ds2781_get_pmod_enabled,
733	ds2781_set_pmod_enabled);
734static DEVICE_ATTR(sense_resistor_value, S_IRUGO | S_IWUSR,
735	ds2781_get_sense_resistor_value, ds2781_set_sense_resistor_value);
736static DEVICE_ATTR(rsgain_setting, S_IRUGO | S_IWUSR, ds2781_get_rsgain_setting,
737	ds2781_set_rsgain_setting);
738static DEVICE_ATTR(pio_pin, S_IRUGO | S_IWUSR, ds2781_get_pio_pin,
739	ds2781_set_pio_pin);
740
741
742static struct attribute *ds2781_attributes[] = {
743	&dev_attr_pmod_enabled.attr,
744	&dev_attr_sense_resistor_value.attr,
745	&dev_attr_rsgain_setting.attr,
746	&dev_attr_pio_pin.attr,
747	NULL
748};
749
750static const struct attribute_group ds2781_attr_group = {
751	.attrs = ds2781_attributes,
752};
753
754static int ds2781_battery_probe(struct platform_device *pdev)
755{
756	struct power_supply_config psy_cfg = {};
757	int ret = 0;
758	struct ds2781_device_info *dev_info;
759
760	dev_info = devm_kzalloc(&pdev->dev, sizeof(*dev_info), GFP_KERNEL);
761	if (!dev_info)
762		return -ENOMEM;
763
764	platform_set_drvdata(pdev, dev_info);
765
766	dev_info->dev			= &pdev->dev;
767	dev_info->w1_dev		= pdev->dev.parent;
768	dev_info->bat_desc.name		= dev_name(&pdev->dev);
769	dev_info->bat_desc.type		= POWER_SUPPLY_TYPE_BATTERY;
770	dev_info->bat_desc.properties	= ds2781_battery_props;
771	dev_info->bat_desc.num_properties = ARRAY_SIZE(ds2781_battery_props);
772	dev_info->bat_desc.get_property	= ds2781_battery_get_property;
773
774	psy_cfg.drv_data		= dev_info;
775
776	dev_info->bat = power_supply_register(&pdev->dev, &dev_info->bat_desc,
777						&psy_cfg);
778	if (IS_ERR(dev_info->bat)) {
779		dev_err(dev_info->dev, "failed to register battery\n");
780		ret = PTR_ERR(dev_info->bat);
781		goto fail;
782	}
783
784	ret = sysfs_create_group(&dev_info->bat->dev.kobj, &ds2781_attr_group);
785	if (ret) {
786		dev_err(dev_info->dev, "failed to create sysfs group\n");
787		goto fail_unregister;
788	}
789
790	ret = sysfs_create_bin_file(&dev_info->bat->dev.kobj,
791					&ds2781_param_eeprom_bin_attr);
792	if (ret) {
793		dev_err(dev_info->dev,
794				"failed to create param eeprom bin file");
795		goto fail_remove_group;
796	}
797
798	ret = sysfs_create_bin_file(&dev_info->bat->dev.kobj,
799					&ds2781_user_eeprom_bin_attr);
800	if (ret) {
801		dev_err(dev_info->dev,
802				"failed to create user eeprom bin file");
803		goto fail_remove_bin_file;
804	}
805
806	return 0;
807
808fail_remove_bin_file:
809	sysfs_remove_bin_file(&dev_info->bat->dev.kobj,
810				&ds2781_param_eeprom_bin_attr);
811fail_remove_group:
812	sysfs_remove_group(&dev_info->bat->dev.kobj, &ds2781_attr_group);
813fail_unregister:
814	power_supply_unregister(dev_info->bat);
815fail:
816	return ret;
817}
818
819static int ds2781_battery_remove(struct platform_device *pdev)
820{
821	struct ds2781_device_info *dev_info = platform_get_drvdata(pdev);
822
823	/*
824	 * Remove attributes before unregistering power supply
825	 * because 'bat' will be freed on power_supply_unregister() call.
826	 */
827	sysfs_remove_group(&dev_info->bat->dev.kobj, &ds2781_attr_group);
828
829	power_supply_unregister(dev_info->bat);
830
831	return 0;
832}
833
834static struct platform_driver ds2781_battery_driver = {
835	.driver = {
836		.name = "ds2781-battery",
837	},
838	.probe	  = ds2781_battery_probe,
839	.remove   = ds2781_battery_remove,
840};
841module_platform_driver(ds2781_battery_driver);
842
843MODULE_LICENSE("GPL");
844MODULE_AUTHOR("Renata Sayakhova <renata@oktetlabs.ru>");
845MODULE_DESCRIPTION("Maxim/Dallas DS2781 Stand-Alone Fuel Gauage IC driver");
846MODULE_ALIAS("platform:ds2781-battery");
847
848