summaryrefslogtreecommitdiff
path: root/drivers/power/power_supply_core.c
blob: 1c517c34e4be8edf7145f93eeabc1768c0295f4a (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
/*
 *  Universal power supply monitor class
 *
 *  Copyright © 2007  Anton Vorontsov <cbou@mail.ru>
 *  Copyright © 2004  Szabolcs Gyurko
 *  Copyright © 2003  Ian Molton <spyro@f2s.com>
 *
 *  Modified: 2004, Oct     Szabolcs Gyurko
 *
 *  You may use this code as per GPL version 2
 */

#include <linux/module.h>
#include <linux/types.h>
#include <linux/init.h>
#include <linux/slab.h>
#include <linux/device.h>
#include <linux/err.h>
#include <linux/power_supply.h>
#include <linux/thermal.h>
#include "power_supply.h"

/* exported for the APM Power driver, APM emulation */
struct class *power_supply_class;
EXPORT_SYMBOL_GPL(power_supply_class);

static struct device_type power_supply_dev_type;

static bool __power_supply_is_supplied_by(struct power_supply *supplier,
					 struct power_supply *supply)
{
	int i;

	if (!supply->supplied_from && !supplier->supplied_to)
		return false;

	/* Support both supplied_to and supplied_from modes */
	if (supply->supplied_from) {
		if (!supplier->name)
			return false;
		for (i = 0; i < supply->num_supplies; i++)
			if (!strcmp(supplier->name, supply->supplied_from[i]))
				return true;
	} else {
		if (!supply->name)
			return false;
		for (i = 0; i < supplier->num_supplicants; i++)
			if (!strcmp(supplier->supplied_to[i], supply->name))
				return true;
	}

	return false;
}

static int __power_supply_changed_work(struct device *dev, void *data)
{
	struct power_supply *psy = (struct power_supply *)data;
	struct power_supply *pst = dev_get_drvdata(dev);

	if (__power_supply_is_supplied_by(psy, pst)) {
		if (pst->external_power_changed)
			pst->external_power_changed(pst);
	}

	return 0;
}

static void power_supply_changed_work(struct work_struct *work)
{
	struct power_supply *psy = container_of(work, struct power_supply,
						changed_work);

	dev_dbg(psy->dev, "%s\n", __func__);

	class_for_each_device(power_supply_class, NULL, psy,
			      __power_supply_changed_work);

	power_supply_update_leds(psy);

	kobject_uevent(&psy->dev->kobj, KOBJ_CHANGE);
}

void power_supply_changed(struct power_supply *psy)
{
	dev_dbg(psy->dev, "%s\n", __func__);

	schedule_work(&psy->changed_work);
}
EXPORT_SYMBOL_GPL(power_supply_changed);

#ifdef CONFIG_OF
#include <linux/of.h>

static int __power_supply_populate_supplied_from(struct device *dev,
						 void *data)
{
	struct power_supply *psy = (struct power_supply *)data;
	struct power_supply *epsy = dev_get_drvdata(dev);
	struct device_node *np;
	int i = 0;

	do {
		np = of_parse_phandle(psy->of_node, "power-supplies", i++);
		if (!np)
			continue;

		if (np == epsy->of_node) {
			dev_info(psy->dev, "%s: Found supply : %s\n",
				psy->name, epsy->name);
			psy->supplied_from[i-1] = (char *)epsy->name;
			psy->num_supplies++;
			break;
		}
	} while (np);

	return 0;
}

static int power_supply_populate_supplied_from(struct power_supply *psy)
{
	int error;

	error = class_for_each_device(power_supply_class, NULL, psy,
				      __power_supply_populate_supplied_from);

	dev_dbg(psy->dev, "%s %d\n", __func__, error);

	return error;
}

static int  __power_supply_find_supply_from_node(struct device *dev,
						 void *data)
{
	struct device_node *np = (struct device_node *)data;
	struct power_supply *epsy = dev_get_drvdata(dev);

	/* return error breaks out of class_for_each_device loop */
	if (epsy->of_node == np)
		return -EINVAL;

	return 0;
}

static int power_supply_find_supply_from_node(struct device_node *supply_node)
{
	int error;
	struct device *dev;
	struct class_dev_iter iter;

	/*
	 * Use iterator to see if any other device is registered.
	 * This is required since class_for_each_device returns 0
	 * if there are no devices registered.
	 */
	class_dev_iter_init(&iter, power_supply_class, NULL, NULL);
	dev = class_dev_iter_next(&iter);

	if (!dev)
		return -EPROBE_DEFER;

	/*
	 * We have to treat the return value as inverted, because if
	 * we return error on not found, then it won't continue looking.
	 * So we trick it by returning error on success to stop looking
	 * once the matching device is found.
	 */
	error = class_for_each_device(power_supply_class, NULL, supply_node,
				       __power_supply_find_supply_from_node);

	return error ? 0 : -EPROBE_DEFER;
}

static int power_supply_check_supplies(struct power_supply *psy)
{
	struct device_node *np;
	int cnt = 0;

	/* If there is already a list honor it */
	if (psy->supplied_from && psy->num_supplies > 0)
		return 0;

	/* No device node found, nothing to do */
	if (!psy->of_node)
		return 0;

	do {
		int ret;

		np = of_parse_phandle(psy->of_node, "power-supplies", cnt++);
		if (!np)
			continue;

		ret = power_supply_find_supply_from_node(np);
		if (ret) {
			dev_dbg(psy->dev, "Failed to find supply, defer!\n");
			return -EPROBE_DEFER;
		}
	} while (np);

	/* All supplies found, allocate char ** array for filling */
	psy->supplied_from = devm_kzalloc(psy->dev, sizeof(psy->supplied_from),
					  GFP_KERNEL);
	if (!psy->supplied_from) {
		dev_err(psy->dev, "Couldn't allocate memory for supply list\n");
		return -ENOMEM;
	}

	*psy->supplied_from = devm_kzalloc(psy->dev, sizeof(char *) * cnt,
					   GFP_KERNEL);
	if (!*psy->supplied_from) {
		dev_err(psy->dev, "Couldn't allocate memory for supply list\n");
		return -ENOMEM;
	}

	return power_supply_populate_supplied_from(psy);
}
#else
static inline int power_supply_check_supplies(struct power_supply *psy)
{
	return 0;
}
#endif

static int __power_supply_am_i_supplied(struct device *dev, void *data)
{
	union power_supply_propval ret = {0,};
	struct power_supply *psy = (struct power_supply *)data;
	struct power_supply *epsy = dev_get_drvdata(dev);

	if (__power_supply_is_supplied_by(epsy, psy))
		if (!epsy->get_property(epsy, POWER_SUPPLY_PROP_ONLINE, &ret)) {
			if (ret.intval)
				return ret.intval;
		}

	return 0;
}

int power_supply_am_i_supplied(struct power_supply *psy)
{
	int error;

	error = class_for_each_device(power_supply_class, NULL, psy,
				      __power_supply_am_i_supplied);

	dev_dbg(psy->dev, "%s %d\n", __func__, error);

	return error;
}
EXPORT_SYMBOL_GPL(power_supply_am_i_supplied);

static int __power_supply_is_system_supplied(struct device *dev, void *data)
{
	union power_supply_propval ret = {0,};
	struct power_supply *psy = dev_get_drvdata(dev);
	unsigned int *count = data;

	(*count)++;
	if (psy->type != POWER_SUPPLY_TYPE_BATTERY) {
		if (psy->get_property(psy, POWER_SUPPLY_PROP_ONLINE, &ret))
			return 0;
		if (ret.intval)
			return ret.intval;
	}
	return 0;
}

int power_supply_is_system_supplied(void)
{
	int error;
	unsigned int count = 0;

	error = class_for_each_device(power_supply_class, NULL, &count,
				      __power_supply_is_system_supplied);

	/*
	 * If no power class device was found at all, most probably we are
	 * running on a desktop system, so assume we are on mains power.
	 */
	if (count == 0)
		return 1;

	return error;
}
EXPORT_SYMBOL_GPL(power_supply_is_system_supplied);

int power_supply_set_battery_charged(struct power_supply *psy)
{
	if (psy->type == POWER_SUPPLY_TYPE_BATTERY && psy->set_charged) {
		psy->set_charged(psy);
		return 0;
	}

	return -EINVAL;
}
EXPORT_SYMBOL_GPL(power_supply_set_battery_charged);

static int power_supply_match_device_by_name(struct device *dev, const void *data)
{
	const char *name = data;
	struct power_supply *psy = dev_get_drvdata(dev);

	return strcmp(psy->name, name) == 0;
}

struct power_supply *power_supply_get_by_name(const char *name)
{
	struct device *dev = class_find_device(power_supply_class, NULL, name,
					power_supply_match_device_by_name);

	return dev ? dev_get_drvdata(dev) : NULL;
}
EXPORT_SYMBOL_GPL(power_supply_get_by_name);

int power_supply_powers(struct power_supply *psy, struct device *dev)
{
	return sysfs_create_link(&psy->dev->kobj, &dev->kobj, "powers");
}
EXPORT_SYMBOL_GPL(power_supply_powers);

static void power_supply_dev_release(struct device *dev)
{
	pr_debug("device: '%s': %s\n", dev_name(dev), __func__);
	kfree(dev);
}

#ifdef CONFIG_THERMAL
static int power_supply_read_temp(struct thermal_zone_device *tzd,
		unsigned long *temp)
{
	struct power_supply *psy;
	union power_supply_propval val;
	int ret;

	WARN_ON(tzd == NULL);
	psy = tzd->devdata;
	ret = psy->get_property(psy, POWER_SUPPLY_PROP_TEMP, &val);

	/* Convert tenths of degree Celsius to milli degree Celsius. */
	if (!ret)
		*temp = val.intval * 100;

	return ret;
}

static struct thermal_zone_device_ops psy_tzd_ops = {
	.get_temp = power_supply_read_temp,
};

static int psy_register_thermal(struct power_supply *psy)
{
	int i;

	/* Register battery zone device psy reports temperature */
	for (i = 0; i < psy->num_properties; i++) {
		if (psy->properties[i] == POWER_SUPPLY_PROP_TEMP) {
			psy->tzd = thermal_zone_device_register(psy->name, 0, 0,
					psy, &psy_tzd_ops, NULL, 0, 0);
			if (IS_ERR(psy->tzd))
				return PTR_ERR(psy->tzd);
			break;
		}
	}
	return 0;
}

static void psy_unregister_thermal(struct power_supply *psy)
{
	if (IS_ERR_OR_NULL(psy->tzd))
		return;
	thermal_zone_device_unregister(psy->tzd);
}

/* thermal cooling device callbacks */
static int ps_get_max_charge_cntl_limit(struct thermal_cooling_device *tcd,
					unsigned long *state)
{
	struct power_supply *psy;
	union power_supply_propval val;
	int ret;

	psy = tcd->devdata;
	ret = psy->get_property(psy,
		POWER_SUPPLY_PROP_CHARGE_CONTROL_LIMIT_MAX, &val);
	if (!ret)
		*state = val.intval;

	return ret;
}

static int ps_get_cur_chrage_cntl_limit(struct thermal_cooling_device *tcd,
					unsigned long *state)
{
	struct power_supply *psy;
	union power_supply_propval val;
	int ret;

	psy = tcd->devdata;
	ret = psy->get_property(psy,
		POWER_SUPPLY_PROP_CHARGE_CONTROL_LIMIT, &val);
	if (!ret)
		*state = val.intval;

	return ret;
}

static int ps_set_cur_charge_cntl_limit(struct thermal_cooling_device *tcd,
					unsigned long state)
{
	struct power_supply *psy;
	union power_supply_propval val;
	int ret;

	psy = tcd->devdata;
	val.intval = state;
	ret = psy->set_property(psy,
		POWER_SUPPLY_PROP_CHARGE_CONTROL_LIMIT, &val);

	return ret;
}

static struct thermal_cooling_device_ops psy_tcd_ops = {
	.get_max_state = ps_get_max_charge_cntl_limit,
	.get_cur_state = ps_get_cur_chrage_cntl_limit,
	.set_cur_state = ps_set_cur_charge_cntl_limit,
};

static int psy_register_cooler(struct power_supply *psy)
{
	int i;

	/* Register for cooling device if psy can control charging */
	for (i = 0; i < psy->num_properties; i++) {
		if (psy->properties[i] ==
				POWER_SUPPLY_PROP_CHARGE_CONTROL_LIMIT) {
			psy->tcd = thermal_cooling_device_register(
							(char *)psy->name,
							psy, &psy_tcd_ops);
			if (IS_ERR(psy->tcd))
				return PTR_ERR(psy->tcd);
			break;
		}
	}
	return 0;
}

static void psy_unregister_cooler(struct power_supply *psy)
{
	if (IS_ERR_OR_NULL(psy->tcd))
		return;
	thermal_cooling_device_unregister(psy->tcd);
}
#else
static int psy_register_thermal(struct power_supply *psy)
{
	return 0;
}

static void psy_unregister_thermal(struct power_supply *psy)
{
}

static int psy_register_cooler(struct power_supply *psy)
{
	return 0;
}

static void psy_unregister_cooler(struct power_supply *psy)
{
}
#endif

int power_supply_register(struct device *parent, struct power_supply *psy)
{
	struct device *dev;
	int rc;

	dev = kzalloc(sizeof(*dev), GFP_KERNEL);
	if (!dev)
		return -ENOMEM;

	device_initialize(dev);

	dev->class = power_supply_class;
	dev->type = &power_supply_dev_type;
	dev->parent = parent;
	dev->release = power_supply_dev_release;
	dev_set_drvdata(dev, psy);
	psy->dev = dev;

	INIT_WORK(&psy->changed_work, power_supply_changed_work);

	rc = power_supply_check_supplies(psy);
	if (rc) {
		dev_info(dev, "Not all required supplies found, defer probe\n");
		goto check_supplies_failed;
	}

	rc = kobject_set_name(&dev->kobj, "%s", psy->name);
	if (rc)
		goto kobject_set_name_failed;

	rc = device_add(dev);
	if (rc)
		goto device_add_failed;

	rc = psy_register_thermal(psy);
	if (rc)
		goto register_thermal_failed;

	rc = psy_register_cooler(psy);
	if (rc)
		goto register_cooler_failed;

	rc = power_supply_create_triggers(psy);
	if (rc)
		goto create_triggers_failed;

	power_supply_changed(psy);

	goto success;

create_triggers_failed:
	psy_unregister_cooler(psy);
register_cooler_failed:
	psy_unregister_thermal(psy);
register_thermal_failed:
	device_del(dev);
kobject_set_name_failed:
device_add_failed:
check_supplies_failed:
	put_device(dev);
success:
	return rc;
}
EXPORT_SYMBOL_GPL(power_supply_register);

void power_supply_unregister(struct power_supply *psy)
{
	cancel_work_sync(&psy->changed_work);
	sysfs_remove_link(&psy->dev->kobj, "powers");
	power_supply_remove_triggers(psy);
	psy_unregister_cooler(psy);
	psy_unregister_thermal(psy);
	device_unregister(psy->dev);
}
EXPORT_SYMBOL_GPL(power_supply_unregister);

static int __init power_supply_class_init(void)
{
	power_supply_class = class_create(THIS_MODULE, "power_supply");

	if (IS_ERR(power_supply_class))
		return PTR_ERR(power_supply_class);

	power_supply_class->dev_uevent = power_supply_uevent;
	power_supply_init_attrs(&power_supply_dev_type);

	return 0;
}

static void __exit power_supply_class_exit(void)
{
	class_destroy(power_supply_class);
}

subsys_initcall(power_supply_class_init);
module_exit(power_supply_class_exit);

MODULE_DESCRIPTION("Universal power supply monitor class");
MODULE_AUTHOR("Ian Molton <spyro@f2s.com>, "
	      "Szabolcs Gyurko, "
	      "Anton Vorontsov <cbou@mail.ru>");
MODULE_LICENSE("GPL");