ds2760_battery.c

  1/*
  2 * Driver for batteries with DS2760 chips inside.
  3 *
  4 * Copyright © 2007 Anton Vorontsov
  5 *	       2004-2007 Matt Reimer
  6 *	       2004 Szabolcs Gyurko
  7 *
  8 * Use consistent with the GNU GPL is permitted,
  9 * provided that this copyright notice is
 10 * preserved in its entirety in all copies and derived works.
 11 *
 12 * Author:  Anton Vorontsov <cbou@mail.ru>
 13 *	    February 2007
 14 *
 15 *	    Matt Reimer <mreimer@vpop.net>
 16 *	    April 2004, 2005, 2007
 17 *
 18 *	    Szabolcs Gyurko <szabolcs.gyurko@tlt.hu>
 19 *	    September 2004
 20 */
 21
 22#include <linux/module.h>
 23#include <linux/param.h>
 24#include <linux/jiffies.h>
 25#include <linux/workqueue.h>
 26#include <linux/pm.h>
 27#include <linux/slab.h>
 28#include <linux/platform_device.h>
 29#include <linux/power_supply.h>
 30#include <linux/suspend.h>
 31#include <linux/w1.h>
 32#include <linux/of.h>
 33
 34static unsigned int cache_time = 1000;
 35module_param(cache_time, uint, 0644);
 36MODULE_PARM_DESC(cache_time, "cache time in milliseconds");
 37
 38static bool pmod_enabled;
 39module_param(pmod_enabled, bool, 0644);
 40MODULE_PARM_DESC(pmod_enabled, "PMOD enable bit");
 41
 42static unsigned int rated_capacity;
 43module_param(rated_capacity, uint, 0644);
 44MODULE_PARM_DESC(rated_capacity, "rated battery capacity, 10*mAh or index");
 45
 46static unsigned int current_accum;
 47module_param(current_accum, uint, 0644);
 48MODULE_PARM_DESC(current_accum, "current accumulator value");
 49
 50#define W1_FAMILY_DS2760		0x30
 51
 52/* Known commands to the DS2760 chip */
 53#define W1_DS2760_SWAP			0xAA
 54#define W1_DS2760_READ_DATA		0x69
 55#define W1_DS2760_WRITE_DATA		0x6C
 56#define W1_DS2760_COPY_DATA		0x48
 57#define W1_DS2760_RECALL_DATA		0xB8
 58#define W1_DS2760_LOCK			0x6A
 59
 60/* Number of valid register addresses */
 61#define DS2760_DATA_SIZE		0x40
 62
 63#define DS2760_PROTECTION_REG		0x00
 64
 65#define DS2760_STATUS_REG		0x01
 66#define DS2760_STATUS_IE		(1 << 2)
 67#define DS2760_STATUS_SWEN		(1 << 3)
 68#define DS2760_STATUS_RNAOP		(1 << 4)
 69#define DS2760_STATUS_PMOD		(1 << 5)
 70
 71#define DS2760_EEPROM_REG		0x07
 72#define DS2760_SPECIAL_FEATURE_REG	0x08
 73#define DS2760_VOLTAGE_MSB		0x0c
 74#define DS2760_VOLTAGE_LSB		0x0d
 75#define DS2760_CURRENT_MSB		0x0e
 76#define DS2760_CURRENT_LSB		0x0f
 77#define DS2760_CURRENT_ACCUM_MSB	0x10
 78#define DS2760_CURRENT_ACCUM_LSB	0x11
 79#define DS2760_TEMP_MSB			0x18
 80#define DS2760_TEMP_LSB			0x19
 81#define DS2760_EEPROM_BLOCK0		0x20
 82#define DS2760_ACTIVE_FULL		0x20
 83#define DS2760_EEPROM_BLOCK1		0x30
 84#define DS2760_STATUS_WRITE_REG		0x31
 85#define DS2760_RATED_CAPACITY		0x32
 86#define DS2760_CURRENT_OFFSET_BIAS	0x33
 87#define DS2760_ACTIVE_EMPTY		0x3b
 88
 89struct ds2760_device_info {
 90	struct device *dev;
 91
 92	/* DS2760 data, valid after calling ds2760_battery_read_status() */
 93	unsigned long update_time;	/* jiffies when data read */
 94	char raw[DS2760_DATA_SIZE];	/* raw DS2760 data */
 95	int voltage_raw;		/* units of 4.88 mV */
 96	int voltage_uV;			/* units of µV */
 97	int current_raw;		/* units of 0.625 mA */
 98	int current_uA;			/* units of µA */
 99	int accum_current_raw;		/* units of 0.25 mAh */
100	int accum_current_uAh;		/* units of µAh */
101	int temp_raw;			/* units of 0.125 °C */
102	int temp_C;			/* units of 0.1 °C */
103	int rated_capacity;		/* units of µAh */
104	int rem_capacity;		/* percentage */
105	int full_active_uAh;		/* units of µAh */
106	int empty_uAh;			/* units of µAh */
107	int life_sec;			/* units of seconds */
108	int charge_status;		/* POWER_SUPPLY_STATUS_* */
109
110	int full_counter;
111	struct power_supply *bat;
112	struct power_supply_desc bat_desc;
113	struct workqueue_struct *monitor_wqueue;
114	struct delayed_work monitor_work;
115	struct notifier_block pm_notifier;
116};
117
118static int w1_ds2760_io(struct device *dev, char *buf, int addr, size_t count,
119			int io)
120{
121	struct w1_slave *sl = container_of(dev, struct w1_slave, dev);
122
123	if (!dev)
124		return 0;
125
126	mutex_lock(&sl->master->bus_mutex);
127
128	if (addr > DS2760_DATA_SIZE || addr < 0) {
129		count = 0;
130		goto out;
131	}
132	if (addr + count > DS2760_DATA_SIZE)
133		count = DS2760_DATA_SIZE - addr;
134
135	if (!w1_reset_select_slave(sl)) {
136		if (!io) {
137			w1_write_8(sl->master, W1_DS2760_READ_DATA);
138			w1_write_8(sl->master, addr);
139			count = w1_read_block(sl->master, buf, count);
140		} else {
141			w1_write_8(sl->master, W1_DS2760_WRITE_DATA);
142			w1_write_8(sl->master, addr);
143			w1_write_block(sl->master, buf, count);
144			/* XXX w1_write_block returns void, not n_written */
145		}
146	}
147
148out:
149	mutex_unlock(&sl->master->bus_mutex);
150
151	return count;
152}
153
154static int w1_ds2760_read(struct device *dev,
155			  char *buf, int addr,
156			  size_t count)
157{
158	return w1_ds2760_io(dev, buf, addr, count, 0);
159}
160
161static int w1_ds2760_write(struct device *dev,
162			   char *buf,
163			   int addr, size_t count)
164{
165	return w1_ds2760_io(dev, buf, addr, count, 1);
166}
167
168static int w1_ds2760_eeprom_cmd(struct device *dev, int addr, int cmd)
169{
170	struct w1_slave *sl = container_of(dev, struct w1_slave, dev);
171
172	if (!dev)
173		return -EINVAL;
174
175	mutex_lock(&sl->master->bus_mutex);
176
177	if (w1_reset_select_slave(sl) == 0) {
178		w1_write_8(sl->master, cmd);
179		w1_write_8(sl->master, addr);
180	}
181
182	mutex_unlock(&sl->master->bus_mutex);
183	return 0;
184}
185
186static int w1_ds2760_store_eeprom(struct device *dev, int addr)
187{
188	return w1_ds2760_eeprom_cmd(dev, addr, W1_DS2760_COPY_DATA);
189}
190
191static int w1_ds2760_recall_eeprom(struct device *dev, int addr)
192{
193	return w1_ds2760_eeprom_cmd(dev, addr, W1_DS2760_RECALL_DATA);
194}
195
196static ssize_t w1_slave_read(struct file *filp, struct kobject *kobj,
197			     const struct bin_attribute *bin_attr, char *buf,
198			     loff_t off, size_t count)
199{
200	struct device *dev = kobj_to_dev(kobj);
201	return w1_ds2760_read(dev, buf, off, count);
202}
203
204static const BIN_ATTR_RO(w1_slave, DS2760_DATA_SIZE);
205
206static const struct bin_attribute *const w1_ds2760_bin_attrs[] = {
207	&bin_attr_w1_slave,
208	NULL,
209};
210
211static const struct attribute_group w1_ds2760_group = {
212	.bin_attrs = w1_ds2760_bin_attrs,
213};
214
215static const struct attribute_group *w1_ds2760_groups[] = {
216	&w1_ds2760_group,
217	NULL,
218};
219/* Some batteries have their rated capacity stored a N * 10 mAh, while
220 * others use an index into this table. */
221static int rated_capacities[] = {
222	0,
223	920,	/* Samsung */
224	920,	/* BYD */
225	920,	/* Lishen */
226	920,	/* NEC */
227	1440,	/* Samsung */
228	1440,	/* BYD */
229	1440,	/* Lishen */
230	1440,	/* NEC */
231	2880,	/* Samsung */
232	2880,	/* BYD */
233	2880,	/* Lishen */
234	2880,	/* NEC */
235};
236
237/* array is level at temps 0°C, 10°C, 20°C, 30°C, 40°C
238 * temp is in Celsius */
239static int battery_interpolate(int array[], int temp)
240{
241	int index, dt;
242
243	if (temp <= 0)
244		return array[0];
245	if (temp >= 40)
246		return array[4];
247
248	index = temp / 10;
249	dt    = temp % 10;
250
251	return array[index] + (((array[index + 1] - array[index]) * dt) / 10);
252}
253
254static int ds2760_battery_read_status(struct ds2760_device_info *di)
255{
256	int ret, i, start, count, scale[5];
257
258	if (di->update_time && time_before(jiffies, di->update_time +
259					   msecs_to_jiffies(cache_time)))
260		return 0;
261
262	/* The first time we read the entire contents of SRAM/EEPROM,
263	 * but after that we just read the interesting bits that change. */
264	if (di->update_time == 0) {
265		start = 0;
266		count = DS2760_DATA_SIZE;
267	} else {
268		start = DS2760_VOLTAGE_MSB;
269		count = DS2760_TEMP_LSB - start + 1;
270	}
271
272	ret = w1_ds2760_read(di->dev, di->raw + start, start, count);
273	if (ret != count) {
274		dev_warn(di->dev, "call to w1_ds2760_read failed (0x%p)\n",
275			 di->dev);
276		return 1;
277	}
278
279	di->update_time = jiffies;
280
281	/* DS2760 reports voltage in units of 4.88mV, but the battery class
282	 * reports in units of uV, so convert by multiplying by 4880. */
283	di->voltage_raw = (di->raw[DS2760_VOLTAGE_MSB] << 3) |
284			  (di->raw[DS2760_VOLTAGE_LSB] >> 5);
285	di->voltage_uV = di->voltage_raw * 4880;
286
287	/* DS2760 reports current in signed units of 0.625mA, but the battery
288	 * class reports in units of µA, so convert by multiplying by 625. */
289	di->current_raw =
290	    (((signed char)di->raw[DS2760_CURRENT_MSB]) << 5) |
291			  (di->raw[DS2760_CURRENT_LSB] >> 3);
292	di->current_uA = di->current_raw * 625;
293
294	/* DS2760 reports accumulated current in signed units of 0.25mAh. */
295	di->accum_current_raw =
296	    (((signed char)di->raw[DS2760_CURRENT_ACCUM_MSB]) << 8) |
297			   di->raw[DS2760_CURRENT_ACCUM_LSB];
298	di->accum_current_uAh = di->accum_current_raw * 250;
299
300	/* DS2760 reports temperature in signed units of 0.125°C, but the
301	 * battery class reports in units of 1/10 °C, so we convert by
302	 * multiplying by .125 * 10 = 1.25. */
303	di->temp_raw = (((signed char)di->raw[DS2760_TEMP_MSB]) << 3) |
304				     (di->raw[DS2760_TEMP_LSB] >> 5);
305	di->temp_C = di->temp_raw + (di->temp_raw / 4);
306
307	/* At least some battery monitors (e.g. HP iPAQ) store the battery's
308	 * maximum rated capacity. */
309	if (di->raw[DS2760_RATED_CAPACITY] < ARRAY_SIZE(rated_capacities))
310		di->rated_capacity = rated_capacities[
311			(unsigned int)di->raw[DS2760_RATED_CAPACITY]];
312	else
313		di->rated_capacity = di->raw[DS2760_RATED_CAPACITY] * 10;
314
315	di->rated_capacity *= 1000; /* convert to µAh */
316
317	/* Calculate the full level at the present temperature. */
318	di->full_active_uAh = di->raw[DS2760_ACTIVE_FULL] << 8 |
319			      di->raw[DS2760_ACTIVE_FULL + 1];
320
321	/* If the full_active_uAh value is not given, fall back to the rated
322	 * capacity. This is likely to happen when chips are not part of the
323	 * battery pack and is therefore not bootstrapped. */
324	if (di->full_active_uAh == 0)
325		di->full_active_uAh = di->rated_capacity / 1000L;
326
327	scale[0] = di->full_active_uAh;
328	for (i = 1; i < 5; i++)
329		scale[i] = scale[i - 1] + di->raw[DS2760_ACTIVE_FULL + 1 + i];
330
331	di->full_active_uAh = battery_interpolate(scale, di->temp_C / 10);
332	di->full_active_uAh *= 1000; /* convert to µAh */
333
334	/* Calculate the empty level at the present temperature. */
335	scale[4] = di->raw[DS2760_ACTIVE_EMPTY + 4];
336	for (i = 3; i >= 0; i--)
337		scale[i] = scale[i + 1] + di->raw[DS2760_ACTIVE_EMPTY + i];
338
339	di->empty_uAh = battery_interpolate(scale, di->temp_C / 10);
340	di->empty_uAh *= 1000; /* convert to µAh */
341
342	if (di->full_active_uAh == di->empty_uAh)
343		di->rem_capacity = 0;
344	else
345		/* From Maxim Application Note 131: remaining capacity =
346		 * ((ICA - Empty Value) / (Full Value - Empty Value)) x 100% */
347		di->rem_capacity = ((di->accum_current_uAh - di->empty_uAh) * 100L) /
348				    (di->full_active_uAh - di->empty_uAh);
349
350	if (di->rem_capacity < 0)
351		di->rem_capacity = 0;
352	if (di->rem_capacity > 100)
353		di->rem_capacity = 100;
354
355	if (di->current_uA < -100L)
356		di->life_sec = -((di->accum_current_uAh - di->empty_uAh) * 36L)
357					/ (di->current_uA / 100L);
358	else
359		di->life_sec = 0;
360
361	return 0;
362}
363
364static void ds2760_battery_set_current_accum(struct ds2760_device_info *di,
365					     unsigned int acr_val)
366{
367	unsigned char acr[2];
368
369	/* acr is in units of 0.25 mAh */
370	acr_val *= 4L;
371	acr_val /= 1000;
372
373	acr[0] = acr_val >> 8;
374	acr[1] = acr_val & 0xff;
375
376	if (w1_ds2760_write(di->dev, acr, DS2760_CURRENT_ACCUM_MSB, 2) < 2)
377		dev_warn(di->dev, "ACR write failed\n");
378}
379
380static void ds2760_battery_update_status(struct ds2760_device_info *di)
381{
382	int old_charge_status = di->charge_status;
383
384	ds2760_battery_read_status(di);
385
386	if (di->charge_status == POWER_SUPPLY_STATUS_UNKNOWN)
387		di->full_counter = 0;
388
389	if (power_supply_am_i_supplied(di->bat)) {
390		if (di->current_uA > 10000) {
391			di->charge_status = POWER_SUPPLY_STATUS_CHARGING;
392			di->full_counter = 0;
393		} else if (di->current_uA < -5000) {
394			if (di->charge_status != POWER_SUPPLY_STATUS_NOT_CHARGING)
395				dev_notice(di->dev, "not enough power to "
396					   "charge\n");
397			di->charge_status = POWER_SUPPLY_STATUS_NOT_CHARGING;
398			di->full_counter = 0;
399		} else if (di->current_uA < 10000 &&
400			    di->charge_status != POWER_SUPPLY_STATUS_FULL) {
401
402			/* Don't consider the battery to be full unless
403			 * we've seen the current < 10 mA at least two
404			 * consecutive times. */
405
406			di->full_counter++;
407
408			if (di->full_counter < 2) {
409				di->charge_status = POWER_SUPPLY_STATUS_CHARGING;
410			} else {
411				di->charge_status = POWER_SUPPLY_STATUS_FULL;
412				ds2760_battery_set_current_accum(di,
413						di->full_active_uAh);
414			}
415		}
416	} else {
417		di->charge_status = POWER_SUPPLY_STATUS_DISCHARGING;
418		di->full_counter = 0;
419	}
420
421	if (di->charge_status != old_charge_status)
422		power_supply_changed(di->bat);
423}
424
425static void ds2760_battery_write_status(struct ds2760_device_info *di,
426					char status)
427{
428	if (status == di->raw[DS2760_STATUS_REG])
429		return;
430
431	w1_ds2760_write(di->dev, &status, DS2760_STATUS_WRITE_REG, 1);
432	w1_ds2760_store_eeprom(di->dev, DS2760_EEPROM_BLOCK1);
433	w1_ds2760_recall_eeprom(di->dev, DS2760_EEPROM_BLOCK1);
434}
435
436static void ds2760_battery_write_rated_capacity(struct ds2760_device_info *di,
437						unsigned char rated_capacity)
438{
439	if (rated_capacity == di->raw[DS2760_RATED_CAPACITY])
440		return;
441
442	w1_ds2760_write(di->dev, &rated_capacity, DS2760_RATED_CAPACITY, 1);
443	w1_ds2760_store_eeprom(di->dev, DS2760_EEPROM_BLOCK1);
444	w1_ds2760_recall_eeprom(di->dev, DS2760_EEPROM_BLOCK1);
445}
446
447static void ds2760_battery_write_active_full(struct ds2760_device_info *di,
448					     int active_full)
449{
450	unsigned char tmp[2] = {
451		active_full >> 8,
452		active_full & 0xff
453	};
454
455	if (tmp[0] == di->raw[DS2760_ACTIVE_FULL] &&
456	    tmp[1] == di->raw[DS2760_ACTIVE_FULL + 1])
457		return;
458
459	w1_ds2760_write(di->dev, tmp, DS2760_ACTIVE_FULL, sizeof(tmp));
460	w1_ds2760_store_eeprom(di->dev, DS2760_EEPROM_BLOCK0);
461	w1_ds2760_recall_eeprom(di->dev, DS2760_EEPROM_BLOCK0);
462
463	/* Write to the di->raw[] buffer directly - the DS2760_ACTIVE_FULL
464	 * values won't be read back by ds2760_battery_read_status() */
465	di->raw[DS2760_ACTIVE_FULL] = tmp[0];
466	di->raw[DS2760_ACTIVE_FULL + 1] = tmp[1];
467}
468
469static void ds2760_battery_work(struct work_struct *work)
470{
471	struct ds2760_device_info *di = container_of(work,
472		struct ds2760_device_info, monitor_work.work);
473	const int interval = HZ * 60;
474
475	dev_dbg(di->dev, "%s\n", __func__);
476
477	ds2760_battery_update_status(di);
478	queue_delayed_work(di->monitor_wqueue, &di->monitor_work, interval);
479}
480
481static void ds2760_battery_external_power_changed(struct power_supply *psy)
482{
483	struct ds2760_device_info *di = power_supply_get_drvdata(psy);
484
485	dev_dbg(di->dev, "%s\n", __func__);
486
487	mod_delayed_work(di->monitor_wqueue, &di->monitor_work, HZ/10);
488}
489
490
491static int ds2760_battery_get_property(struct power_supply *psy,
492				       enum power_supply_property psp,
493				       union power_supply_propval *val)
494{
495	struct ds2760_device_info *di = power_supply_get_drvdata(psy);
496
497	switch (psp) {
498	case POWER_SUPPLY_PROP_STATUS:
499		val->intval = di->charge_status;
500		return 0;
501	default:
502		break;
503	}
504
505	ds2760_battery_read_status(di);
506
507	switch (psp) {
508	case POWER_SUPPLY_PROP_VOLTAGE_NOW:
509		val->intval = di->voltage_uV;
510		break;
511	case POWER_SUPPLY_PROP_CURRENT_NOW:
512		val->intval = di->current_uA;
513		break;
514	case POWER_SUPPLY_PROP_CHARGE_FULL_DESIGN:
515		val->intval = di->rated_capacity;
516		break;
517	case POWER_SUPPLY_PROP_CHARGE_FULL:
518		val->intval = di->full_active_uAh;
519		break;
520	case POWER_SUPPLY_PROP_CHARGE_EMPTY:
521		val->intval = di->empty_uAh;
522		break;
523	case POWER_SUPPLY_PROP_CHARGE_NOW:
524		val->intval = di->accum_current_uAh;
525		break;
526	case POWER_SUPPLY_PROP_TEMP:
527		val->intval = di->temp_C;
528		break;
529	case POWER_SUPPLY_PROP_TIME_TO_EMPTY_NOW:
530		val->intval = di->life_sec;
531		break;
532	case POWER_SUPPLY_PROP_CAPACITY:
533		val->intval = di->rem_capacity;
534		break;
535	default:
536		return -EINVAL;
537	}
538
539	return 0;
540}
541
542static int ds2760_battery_set_property(struct power_supply *psy,
543				       enum power_supply_property psp,
544				       const union power_supply_propval *val)
545{
546	struct ds2760_device_info *di = power_supply_get_drvdata(psy);
547
548	switch (psp) {
549	case POWER_SUPPLY_PROP_CHARGE_FULL:
550		/* the interface counts in uAh, convert the value */
551		ds2760_battery_write_active_full(di, val->intval / 1000L);
552		break;
553
554	case POWER_SUPPLY_PROP_CHARGE_NOW:
555		/* ds2760_battery_set_current_accum() does the conversion */
556		ds2760_battery_set_current_accum(di, val->intval);
557		break;
558
559	default:
560		return -EPERM;
561	}
562
563	return 0;
564}
565
566static int ds2760_battery_property_is_writeable(struct power_supply *psy,
567						enum power_supply_property psp)
568{
569	switch (psp) {
570	case POWER_SUPPLY_PROP_CHARGE_FULL:
571	case POWER_SUPPLY_PROP_CHARGE_NOW:
572		return 1;
573
574	default:
575		break;
576	}
577
578	return 0;
579}
580
581static enum power_supply_property ds2760_battery_props[] = {
582	POWER_SUPPLY_PROP_STATUS,
583	POWER_SUPPLY_PROP_VOLTAGE_NOW,
584	POWER_SUPPLY_PROP_CURRENT_NOW,
585	POWER_SUPPLY_PROP_CHARGE_FULL_DESIGN,
586	POWER_SUPPLY_PROP_CHARGE_FULL,
587	POWER_SUPPLY_PROP_CHARGE_EMPTY,
588	POWER_SUPPLY_PROP_CHARGE_NOW,
589	POWER_SUPPLY_PROP_TEMP,
590	POWER_SUPPLY_PROP_TIME_TO_EMPTY_NOW,
591	POWER_SUPPLY_PROP_CAPACITY,
592};
593
594static int ds2760_pm_notifier(struct notifier_block *notifier,
595			      unsigned long pm_event,
596			      void *unused)
597{
598	struct ds2760_device_info *di =
599		container_of(notifier, struct ds2760_device_info, pm_notifier);
600
601	switch (pm_event) {
602	case PM_HIBERNATION_PREPARE:
603	case PM_SUSPEND_PREPARE:
604		di->charge_status = POWER_SUPPLY_STATUS_UNKNOWN;
605		break;
606
607	case PM_POST_RESTORE:
608	case PM_POST_HIBERNATION:
609	case PM_POST_SUSPEND:
610		di->charge_status = POWER_SUPPLY_STATUS_UNKNOWN;
611		power_supply_changed(di->bat);
612		mod_delayed_work(di->monitor_wqueue, &di->monitor_work, HZ);
613
614		break;
615
616	case PM_RESTORE_PREPARE:
617	default:
618		break;
619	}
620
621	return NOTIFY_DONE;
622}
623
624static int w1_ds2760_add_slave(struct w1_slave *sl)
625{
626	struct power_supply_config psy_cfg = {};
627	struct ds2760_device_info *di;
628	struct device *dev = &sl->dev;
629	int retval = 0;
630	char name[32];
631	char status;
632
633	di = devm_kzalloc(dev, sizeof(*di), GFP_KERNEL);
634	if (!di) {
635		retval = -ENOMEM;
636		goto di_alloc_failed;
637	}
638
639	snprintf(name, sizeof(name), "ds2760-battery.%d", dev->id);
640
641	di->dev				= dev;
642	di->bat_desc.name		= name;
643	di->bat_desc.type		= POWER_SUPPLY_TYPE_BATTERY;
644	di->bat_desc.properties		= ds2760_battery_props;
645	di->bat_desc.num_properties	= ARRAY_SIZE(ds2760_battery_props);
646	di->bat_desc.get_property	= ds2760_battery_get_property;
647	di->bat_desc.set_property	= ds2760_battery_set_property;
648	di->bat_desc.property_is_writeable =
649				  ds2760_battery_property_is_writeable;
650	di->bat_desc.external_power_changed =
651				  ds2760_battery_external_power_changed;
652
653	psy_cfg.drv_data = di;
654	psy_cfg.fwnode = dev_fwnode(dev);
655
656	if (dev->of_node) {
657		u32 tmp;
658
659		if (!of_property_read_bool(dev->of_node, "maxim,pmod-enabled"))
660			pmod_enabled = true;
661
662		if (!of_property_read_u32(dev->of_node,
663					  "maxim,cache-time-ms", &tmp))
664			cache_time = tmp;
665
666		if (!of_property_read_u32(dev->of_node,
667					  "rated-capacity-microamp-hours",
668					  &tmp))
669			rated_capacity = tmp / 10; /* property is in mAh */
670	}
671
672	di->charge_status = POWER_SUPPLY_STATUS_UNKNOWN;
673
674	sl->family_data = di;
675
676	/* enable sleep mode feature */
677	ds2760_battery_read_status(di);
678	status = di->raw[DS2760_STATUS_REG];
679	if (pmod_enabled)
680		status |= DS2760_STATUS_PMOD;
681	else
682		status &= ~DS2760_STATUS_PMOD;
683
684	ds2760_battery_write_status(di, status);
685
686	/* set rated capacity from module param or device tree */
687	if (rated_capacity)
688		ds2760_battery_write_rated_capacity(di, rated_capacity);
689
690	/* set current accumulator if given as parameter.
691	 * this should only be done for bootstrapping the value */
692	if (current_accum)
693		ds2760_battery_set_current_accum(di, current_accum);
694
695	di->bat = devm_power_supply_register(dev, &di->bat_desc, &psy_cfg);
696	if (IS_ERR(di->bat)) {
697		dev_err(di->dev, "failed to register battery\n");
698		retval = PTR_ERR(di->bat);
699		goto batt_failed;
700	}
701
702	INIT_DELAYED_WORK(&di->monitor_work, ds2760_battery_work);
703	di->monitor_wqueue = alloc_ordered_workqueue(name, WQ_MEM_RECLAIM);
704	if (!di->monitor_wqueue) {
705		retval = -ESRCH;
706		goto workqueue_failed;
707	}
708	queue_delayed_work(di->monitor_wqueue, &di->monitor_work, HZ * 1);
709
710	di->pm_notifier.notifier_call = ds2760_pm_notifier;
711	register_pm_notifier(&di->pm_notifier);
712
713	goto success;
714
715workqueue_failed:
716batt_failed:
717di_alloc_failed:
718success:
719	return retval;
720}
721
722static void w1_ds2760_remove_slave(struct w1_slave *sl)
723{
724	struct ds2760_device_info *di = sl->family_data;
725
726	unregister_pm_notifier(&di->pm_notifier);
727	cancel_delayed_work_sync(&di->monitor_work);
728	destroy_workqueue(di->monitor_wqueue);
729}
730
731#ifdef CONFIG_OF
732static const struct of_device_id w1_ds2760_of_ids[] = {
733	{ .compatible = "maxim,ds2760" },
734	{}
735};
736#endif
737
738static const struct w1_family_ops w1_ds2760_fops = {
739	.add_slave	= w1_ds2760_add_slave,
740	.remove_slave	= w1_ds2760_remove_slave,
741	.groups		= w1_ds2760_groups,
742};
743
744static struct w1_family w1_ds2760_family = {
745	.fid		= W1_FAMILY_DS2760,
746	.fops		= &w1_ds2760_fops,
747	.of_match_table	= of_match_ptr(w1_ds2760_of_ids),
748};
749module_w1_family(w1_ds2760_family);
750
751MODULE_AUTHOR("Szabolcs Gyurko <szabolcs.gyurko@tlt.hu>, "
752	      "Matt Reimer <mreimer@vpop.net>, "
753	      "Anton Vorontsov <cbou@mail.ru>");
754MODULE_DESCRIPTION("1-wire Driver Dallas 2760 battery monitor chip");
755MODULE_LICENSE("GPL");
756MODULE_ALIAS("w1-family-" __stringify(W1_FAMILY_DS2760));