xref: /linux/drivers/power/supply/ds2760_battery.c (revision 22c5696e3fe029f4fc2decbe7cc6663b5d281223)
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 
34 static unsigned int cache_time = 1000;
35 module_param(cache_time, uint, 0644);
36 MODULE_PARM_DESC(cache_time, "cache time in milliseconds");
37 
38 static bool pmod_enabled;
39 module_param(pmod_enabled, bool, 0644);
40 MODULE_PARM_DESC(pmod_enabled, "PMOD enable bit");
41 
42 static unsigned int rated_capacity;
43 module_param(rated_capacity, uint, 0644);
44 MODULE_PARM_DESC(rated_capacity, "rated battery capacity, 10*mAh or index");
45 
46 static unsigned int current_accum;
47 module_param(current_accum, uint, 0644);
48 MODULE_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 
89 struct 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 
w1_ds2760_io(struct device * dev,char * buf,int addr,size_t count,int io)118 static 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 
148 out:
149 	mutex_unlock(&sl->master->bus_mutex);
150 
151 	return count;
152 }
153 
w1_ds2760_read(struct device * dev,char * buf,int addr,size_t count)154 static 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 
w1_ds2760_write(struct device * dev,char * buf,int addr,size_t count)161 static 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 
w1_ds2760_eeprom_cmd(struct device * dev,int addr,int cmd)168 static 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 
w1_ds2760_store_eeprom(struct device * dev,int addr)186 static 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 
w1_ds2760_recall_eeprom(struct device * dev,int addr)191 static 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 
w1_slave_read(struct file * filp,struct kobject * kobj,const struct bin_attribute * bin_attr,char * buf,loff_t off,size_t count)196 static 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 
204 static const BIN_ATTR_RO(w1_slave, DS2760_DATA_SIZE);
205 
206 static const struct bin_attribute *const w1_ds2760_bin_attrs[] = {
207 	&bin_attr_w1_slave,
208 	NULL,
209 };
210 
211 static const struct attribute_group w1_ds2760_group = {
212 	.bin_attrs = w1_ds2760_bin_attrs,
213 };
214 
215 static 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. */
221 static 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 */
battery_interpolate(int array[],int temp)239 static 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 
ds2760_battery_read_status(struct ds2760_device_info * di)254 static 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 
ds2760_battery_set_current_accum(struct ds2760_device_info * di,unsigned int acr_val)364 static 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 
ds2760_battery_update_status(struct ds2760_device_info * di)380 static 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 
ds2760_battery_write_status(struct ds2760_device_info * di,char status)425 static 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 
ds2760_battery_write_rated_capacity(struct ds2760_device_info * di,unsigned char rated_capacity)436 static 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 
ds2760_battery_write_active_full(struct ds2760_device_info * di,int active_full)447 static 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 
ds2760_battery_work(struct work_struct * work)469 static 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 
ds2760_battery_external_power_changed(struct power_supply * psy)481 static 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 
ds2760_battery_get_property(struct power_supply * psy,enum power_supply_property psp,union power_supply_propval * val)491 static 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 
ds2760_battery_set_property(struct power_supply * psy,enum power_supply_property psp,const union power_supply_propval * val)542 static 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 
ds2760_battery_property_is_writeable(struct power_supply * psy,enum power_supply_property psp)566 static 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 
581 static 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 
ds2760_pm_notifier(struct notifier_block * notifier,unsigned long pm_event,void * unused)594 static 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 
w1_ds2760_add_slave(struct w1_slave * sl)624 static 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 
715 workqueue_failed:
716 batt_failed:
717 di_alloc_failed:
718 success:
719 	return retval;
720 }
721 
w1_ds2760_remove_slave(struct w1_slave * sl)722 static 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
732 static const struct of_device_id w1_ds2760_of_ids[] = {
733 	{ .compatible = "maxim,ds2760" },
734 	{}
735 };
736 #endif
737 
738 static 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 
744 static 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 };
749 module_w1_family(w1_ds2760_family);
750 
751 MODULE_AUTHOR("Szabolcs Gyurko <szabolcs.gyurko@tlt.hu>, "
752 	      "Matt Reimer <mreimer@vpop.net>, "
753 	      "Anton Vorontsov <cbou@mail.ru>");
754 MODULE_DESCRIPTION("1-wire Driver Dallas 2760 battery monitor chip");
755 MODULE_LICENSE("GPL");
756 MODULE_ALIAS("w1-family-" __stringify(W1_FAMILY_DS2760));
757