1 /*
2 * Universal power supply monitor class
3 *
4 * Copyright © 2007 Anton Vorontsov <cbou@mail.ru>
5 * Copyright © 2004 Szabolcs Gyurko
6 * Copyright © 2003 Ian Molton <spyro@f2s.com>
7 *
8 * Modified: 2004, Oct Szabolcs Gyurko
9 *
10 * You may use this code as per GPL version 2
11 */
12
13 #include <linux/module.h>
14 #include <linux/types.h>
15 #include <linux/init.h>
16 #include <linux/slab.h>
17 #include <linux/device.h>
18 #include <linux/notifier.h>
19 #include <linux/err.h>
20 #include <linux/power_supply.h>
21 #include <linux/thermal.h>
22 #include "power_supply.h"
23
24 /* exported for the APM Power driver, APM emulation */
25 struct class *power_supply_class;
26 EXPORT_SYMBOL_GPL(power_supply_class);
27
28 ATOMIC_NOTIFIER_HEAD(power_supply_notifier);
29 EXPORT_SYMBOL_GPL(power_supply_notifier);
30
31 static struct device_type power_supply_dev_type;
32
__power_supply_is_supplied_by(struct power_supply * supplier,struct power_supply * supply)33 static bool __power_supply_is_supplied_by(struct power_supply *supplier,
34 struct power_supply *supply)
35 {
36 int i;
37
38 if (!supply->supplied_from && !supplier->supplied_to)
39 return false;
40
41 /* Support both supplied_to and supplied_from modes */
42 if (supply->supplied_from) {
43 if (!supplier->name)
44 return false;
45 for (i = 0; i < supply->num_supplies; i++)
46 if (!strcmp(supplier->name, supply->supplied_from[i]))
47 return true;
48 } else {
49 if (!supply->name)
50 return false;
51 for (i = 0; i < supplier->num_supplicants; i++)
52 if (!strcmp(supplier->supplied_to[i], supply->name))
53 return true;
54 }
55
56 return false;
57 }
58
__power_supply_changed_work(struct device * dev,void * data)59 static int __power_supply_changed_work(struct device *dev, void *data)
60 {
61 struct power_supply *psy = data;
62 struct power_supply *pst = dev_get_drvdata(dev);
63
64 if (__power_supply_is_supplied_by(psy, pst)) {
65 if (pst->external_power_changed)
66 pst->external_power_changed(pst);
67 }
68
69 return 0;
70 }
71
power_supply_changed_work(struct work_struct * work)72 static void power_supply_changed_work(struct work_struct *work)
73 {
74 unsigned long flags;
75 struct power_supply *psy = container_of(work, struct power_supply,
76 changed_work);
77
78 dev_dbg(psy->dev, "%s\n", __func__);
79
80 spin_lock_irqsave(&psy->changed_lock, flags);
81 /*
82 * Check 'changed' here to avoid issues due to race between
83 * power_supply_changed() and this routine. In worst case
84 * power_supply_changed() can be called again just before we take above
85 * lock. During the first call of this routine we will mark 'changed' as
86 * false and it will stay false for the next call as well.
87 */
88 if (likely(psy->changed)) {
89 psy->changed = false;
90 spin_unlock_irqrestore(&psy->changed_lock, flags);
91 class_for_each_device(power_supply_class, NULL, psy,
92 __power_supply_changed_work);
93 power_supply_update_leds(psy);
94 atomic_notifier_call_chain(&power_supply_notifier,
95 PSY_EVENT_PROP_CHANGED, psy);
96 kobject_uevent(&psy->dev->kobj, KOBJ_CHANGE);
97 spin_lock_irqsave(&psy->changed_lock, flags);
98 }
99
100 /*
101 * Hold the wakeup_source until all events are processed.
102 * power_supply_changed() might have called again and have set 'changed'
103 * to true.
104 */
105 if (likely(!psy->changed))
106 pm_relax(psy->dev);
107 spin_unlock_irqrestore(&psy->changed_lock, flags);
108 }
109
power_supply_changed(struct power_supply * psy)110 void power_supply_changed(struct power_supply *psy)
111 {
112 unsigned long flags;
113
114 dev_dbg(psy->dev, "%s\n", __func__);
115
116 spin_lock_irqsave(&psy->changed_lock, flags);
117 psy->changed = true;
118 pm_stay_awake(psy->dev);
119 spin_unlock_irqrestore(&psy->changed_lock, flags);
120 schedule_work(&psy->changed_work);
121 }
122 EXPORT_SYMBOL_GPL(power_supply_changed);
123
124 #ifdef CONFIG_OF
125 #include <linux/of.h>
126
__power_supply_populate_supplied_from(struct device * dev,void * data)127 static int __power_supply_populate_supplied_from(struct device *dev,
128 void *data)
129 {
130 struct power_supply *psy = data;
131 struct power_supply *epsy = dev_get_drvdata(dev);
132 struct device_node *np;
133 int i = 0;
134
135 do {
136 np = of_parse_phandle(psy->of_node, "power-supplies", i++);
137 if (!np)
138 break;
139
140 if (np == epsy->of_node) {
141 dev_info(psy->dev, "%s: Found supply : %s\n",
142 psy->name, epsy->name);
143 psy->supplied_from[i-1] = (char *)epsy->name;
144 psy->num_supplies++;
145 of_node_put(np);
146 break;
147 }
148 of_node_put(np);
149 } while (np);
150
151 return 0;
152 }
153
power_supply_populate_supplied_from(struct power_supply * psy)154 static int power_supply_populate_supplied_from(struct power_supply *psy)
155 {
156 int error;
157
158 error = class_for_each_device(power_supply_class, NULL, psy,
159 __power_supply_populate_supplied_from);
160
161 dev_dbg(psy->dev, "%s %d\n", __func__, error);
162
163 return error;
164 }
165
__power_supply_find_supply_from_node(struct device * dev,void * data)166 static int __power_supply_find_supply_from_node(struct device *dev,
167 void *data)
168 {
169 struct device_node *np = data;
170 struct power_supply *epsy = dev_get_drvdata(dev);
171
172 /* returning non-zero breaks out of class_for_each_device loop */
173 if (epsy->of_node == np)
174 return 1;
175
176 return 0;
177 }
178
power_supply_find_supply_from_node(struct device_node * supply_node)179 static int power_supply_find_supply_from_node(struct device_node *supply_node)
180 {
181 int error;
182
183 /*
184 * class_for_each_device() either returns its own errors or values
185 * returned by __power_supply_find_supply_from_node().
186 *
187 * __power_supply_find_supply_from_node() will return 0 (no match)
188 * or 1 (match).
189 *
190 * We return 0 if class_for_each_device() returned 1, -EPROBE_DEFER if
191 * it returned 0, or error as returned by it.
192 */
193 error = class_for_each_device(power_supply_class, NULL, supply_node,
194 __power_supply_find_supply_from_node);
195
196 return error ? (error == 1 ? 0 : error) : -EPROBE_DEFER;
197 }
198
power_supply_check_supplies(struct power_supply * psy)199 static int power_supply_check_supplies(struct power_supply *psy)
200 {
201 struct device_node *np;
202 int cnt = 0;
203
204 /* If there is already a list honor it */
205 if (psy->supplied_from && psy->num_supplies > 0)
206 return 0;
207
208 /* No device node found, nothing to do */
209 if (!psy->of_node)
210 return 0;
211
212 do {
213 int ret;
214
215 np = of_parse_phandle(psy->of_node, "power-supplies", cnt++);
216 if (!np)
217 break;
218
219 ret = power_supply_find_supply_from_node(np);
220 of_node_put(np);
221
222 if (ret) {
223 dev_dbg(psy->dev, "Failed to find supply!\n");
224 return ret;
225 }
226 } while (np);
227
228 /* Missing valid "power-supplies" entries */
229 if (cnt == 1)
230 return 0;
231
232 /* All supplies found, allocate char ** array for filling */
233 psy->supplied_from = devm_kzalloc(psy->dev, sizeof(psy->supplied_from),
234 GFP_KERNEL);
235 if (!psy->supplied_from) {
236 dev_err(psy->dev, "Couldn't allocate memory for supply list\n");
237 return -ENOMEM;
238 }
239
240 *psy->supplied_from = devm_kzalloc(psy->dev, sizeof(char *) * (cnt - 1),
241 GFP_KERNEL);
242 if (!*psy->supplied_from) {
243 dev_err(psy->dev, "Couldn't allocate memory for supply list\n");
244 return -ENOMEM;
245 }
246
247 return power_supply_populate_supplied_from(psy);
248 }
249 #else
power_supply_check_supplies(struct power_supply * psy)250 static inline int power_supply_check_supplies(struct power_supply *psy)
251 {
252 return 0;
253 }
254 #endif
255
__power_supply_am_i_supplied(struct device * dev,void * data)256 static int __power_supply_am_i_supplied(struct device *dev, void *data)
257 {
258 union power_supply_propval ret = {0,};
259 struct power_supply *psy = data;
260 struct power_supply *epsy = dev_get_drvdata(dev);
261
262 if (__power_supply_is_supplied_by(epsy, psy))
263 if (!epsy->get_property(epsy, POWER_SUPPLY_PROP_ONLINE, &ret))
264 return ret.intval;
265
266 return 0;
267 }
268
power_supply_am_i_supplied(struct power_supply * psy)269 int power_supply_am_i_supplied(struct power_supply *psy)
270 {
271 int error;
272
273 error = class_for_each_device(power_supply_class, NULL, psy,
274 __power_supply_am_i_supplied);
275
276 dev_dbg(psy->dev, "%s %d\n", __func__, error);
277
278 return error;
279 }
280 EXPORT_SYMBOL_GPL(power_supply_am_i_supplied);
281
__power_supply_is_system_supplied(struct device * dev,void * data)282 static int __power_supply_is_system_supplied(struct device *dev, void *data)
283 {
284 union power_supply_propval ret = {0,};
285 struct power_supply *psy = dev_get_drvdata(dev);
286 unsigned int *count = data;
287
288 (*count)++;
289 if (psy->type != POWER_SUPPLY_TYPE_BATTERY)
290 if (!psy->get_property(psy, POWER_SUPPLY_PROP_ONLINE, &ret))
291 return ret.intval;
292
293 return 0;
294 }
295
power_supply_is_system_supplied(void)296 int power_supply_is_system_supplied(void)
297 {
298 int error;
299 unsigned int count = 0;
300
301 error = class_for_each_device(power_supply_class, NULL, &count,
302 __power_supply_is_system_supplied);
303
304 /*
305 * If no power class device was found at all, most probably we are
306 * running on a desktop system, so assume we are on mains power.
307 */
308 if (count == 0)
309 return 1;
310
311 return error;
312 }
313 EXPORT_SYMBOL_GPL(power_supply_is_system_supplied);
314
power_supply_set_battery_charged(struct power_supply * psy)315 int power_supply_set_battery_charged(struct power_supply *psy)
316 {
317 if (psy->type == POWER_SUPPLY_TYPE_BATTERY && psy->set_charged) {
318 psy->set_charged(psy);
319 return 0;
320 }
321
322 return -EINVAL;
323 }
324 EXPORT_SYMBOL_GPL(power_supply_set_battery_charged);
325
power_supply_match_device_by_name(struct device * dev,const void * data)326 static int power_supply_match_device_by_name(struct device *dev, const void *data)
327 {
328 const char *name = data;
329 struct power_supply *psy = dev_get_drvdata(dev);
330
331 return strcmp(psy->name, name) == 0;
332 }
333
power_supply_get_by_name(const char * name)334 struct power_supply *power_supply_get_by_name(const char *name)
335 {
336 struct device *dev = class_find_device(power_supply_class, NULL, name,
337 power_supply_match_device_by_name);
338
339 return dev ? dev_get_drvdata(dev) : NULL;
340 }
341 EXPORT_SYMBOL_GPL(power_supply_get_by_name);
342
343 #ifdef CONFIG_OF
power_supply_match_device_node(struct device * dev,const void * data)344 static int power_supply_match_device_node(struct device *dev, const void *data)
345 {
346 return dev->parent && dev->parent->of_node == data;
347 }
348
power_supply_get_by_phandle(struct device_node * np,const char * property)349 struct power_supply *power_supply_get_by_phandle(struct device_node *np,
350 const char *property)
351 {
352 struct device_node *power_supply_np;
353 struct device *dev;
354
355 power_supply_np = of_parse_phandle(np, property, 0);
356 if (!power_supply_np)
357 return ERR_PTR(-ENODEV);
358
359 dev = class_find_device(power_supply_class, NULL, power_supply_np,
360 power_supply_match_device_node);
361
362 of_node_put(power_supply_np);
363
364 return dev ? dev_get_drvdata(dev) : NULL;
365 }
366 EXPORT_SYMBOL_GPL(power_supply_get_by_phandle);
367 #endif /* CONFIG_OF */
368
power_supply_powers(struct power_supply * psy,struct device * dev)369 int power_supply_powers(struct power_supply *psy, struct device *dev)
370 {
371 return sysfs_create_link(&psy->dev->kobj, &dev->kobj, "powers");
372 }
373 EXPORT_SYMBOL_GPL(power_supply_powers);
374
power_supply_dev_release(struct device * dev)375 static void power_supply_dev_release(struct device *dev)
376 {
377 pr_debug("device: '%s': %s\n", dev_name(dev), __func__);
378 kfree(dev);
379 }
380
power_supply_reg_notifier(struct notifier_block * nb)381 int power_supply_reg_notifier(struct notifier_block *nb)
382 {
383 return atomic_notifier_chain_register(&power_supply_notifier, nb);
384 }
385 EXPORT_SYMBOL_GPL(power_supply_reg_notifier);
386
power_supply_unreg_notifier(struct notifier_block * nb)387 void power_supply_unreg_notifier(struct notifier_block *nb)
388 {
389 atomic_notifier_chain_unregister(&power_supply_notifier, nb);
390 }
391 EXPORT_SYMBOL_GPL(power_supply_unreg_notifier);
392
393 #ifdef CONFIG_THERMAL
power_supply_read_temp(struct thermal_zone_device * tzd,unsigned long * temp)394 static int power_supply_read_temp(struct thermal_zone_device *tzd,
395 unsigned long *temp)
396 {
397 struct power_supply *psy;
398 union power_supply_propval val;
399 int ret;
400
401 WARN_ON(tzd == NULL);
402 psy = tzd->devdata;
403 ret = psy->get_property(psy, POWER_SUPPLY_PROP_TEMP, &val);
404
405 /* Convert tenths of degree Celsius to milli degree Celsius. */
406 if (!ret)
407 *temp = val.intval * 100;
408
409 return ret;
410 }
411
412 static struct thermal_zone_device_ops psy_tzd_ops = {
413 .get_temp = power_supply_read_temp,
414 };
415
psy_register_thermal(struct power_supply * psy)416 static int psy_register_thermal(struct power_supply *psy)
417 {
418 int i;
419
420 if (psy->no_thermal)
421 return 0;
422
423 /* Register battery zone device psy reports temperature */
424 for (i = 0; i < psy->num_properties; i++) {
425 if (psy->properties[i] == POWER_SUPPLY_PROP_TEMP) {
426 psy->tzd = thermal_zone_device_register(psy->name, 0, 0,
427 psy, &psy_tzd_ops, NULL, 0, 0);
428 return PTR_ERR_OR_ZERO(psy->tzd);
429 }
430 }
431 return 0;
432 }
433
psy_unregister_thermal(struct power_supply * psy)434 static void psy_unregister_thermal(struct power_supply *psy)
435 {
436 if (IS_ERR_OR_NULL(psy->tzd))
437 return;
438 thermal_zone_device_unregister(psy->tzd);
439 }
440
441 /* thermal cooling device callbacks */
ps_get_max_charge_cntl_limit(struct thermal_cooling_device * tcd,unsigned long * state)442 static int ps_get_max_charge_cntl_limit(struct thermal_cooling_device *tcd,
443 unsigned long *state)
444 {
445 struct power_supply *psy;
446 union power_supply_propval val;
447 int ret;
448
449 psy = tcd->devdata;
450 ret = psy->get_property(psy,
451 POWER_SUPPLY_PROP_CHARGE_CONTROL_LIMIT_MAX, &val);
452 if (!ret)
453 *state = val.intval;
454
455 return ret;
456 }
457
ps_get_cur_chrage_cntl_limit(struct thermal_cooling_device * tcd,unsigned long * state)458 static int ps_get_cur_chrage_cntl_limit(struct thermal_cooling_device *tcd,
459 unsigned long *state)
460 {
461 struct power_supply *psy;
462 union power_supply_propval val;
463 int ret;
464
465 psy = tcd->devdata;
466 ret = psy->get_property(psy,
467 POWER_SUPPLY_PROP_CHARGE_CONTROL_LIMIT, &val);
468 if (!ret)
469 *state = val.intval;
470
471 return ret;
472 }
473
ps_set_cur_charge_cntl_limit(struct thermal_cooling_device * tcd,unsigned long state)474 static int ps_set_cur_charge_cntl_limit(struct thermal_cooling_device *tcd,
475 unsigned long state)
476 {
477 struct power_supply *psy;
478 union power_supply_propval val;
479 int ret;
480
481 psy = tcd->devdata;
482 val.intval = state;
483 ret = psy->set_property(psy,
484 POWER_SUPPLY_PROP_CHARGE_CONTROL_LIMIT, &val);
485
486 return ret;
487 }
488
489 static struct thermal_cooling_device_ops psy_tcd_ops = {
490 .get_max_state = ps_get_max_charge_cntl_limit,
491 .get_cur_state = ps_get_cur_chrage_cntl_limit,
492 .set_cur_state = ps_set_cur_charge_cntl_limit,
493 };
494
psy_register_cooler(struct power_supply * psy)495 static int psy_register_cooler(struct power_supply *psy)
496 {
497 int i;
498
499 /* Register for cooling device if psy can control charging */
500 for (i = 0; i < psy->num_properties; i++) {
501 if (psy->properties[i] ==
502 POWER_SUPPLY_PROP_CHARGE_CONTROL_LIMIT) {
503 psy->tcd = thermal_cooling_device_register(
504 (char *)psy->name,
505 psy, &psy_tcd_ops);
506 return PTR_ERR_OR_ZERO(psy->tcd);
507 }
508 }
509 return 0;
510 }
511
psy_unregister_cooler(struct power_supply * psy)512 static void psy_unregister_cooler(struct power_supply *psy)
513 {
514 if (IS_ERR_OR_NULL(psy->tcd))
515 return;
516 thermal_cooling_device_unregister(psy->tcd);
517 }
518 #else
psy_register_thermal(struct power_supply * psy)519 static int psy_register_thermal(struct power_supply *psy)
520 {
521 return 0;
522 }
523
psy_unregister_thermal(struct power_supply * psy)524 static void psy_unregister_thermal(struct power_supply *psy)
525 {
526 }
527
psy_register_cooler(struct power_supply * psy)528 static int psy_register_cooler(struct power_supply *psy)
529 {
530 return 0;
531 }
532
psy_unregister_cooler(struct power_supply * psy)533 static void psy_unregister_cooler(struct power_supply *psy)
534 {
535 }
536 #endif
537
__power_supply_register(struct device * parent,struct power_supply * psy,bool ws)538 static int __power_supply_register(struct device *parent,
539 struct power_supply *psy, bool ws)
540 {
541 struct device *dev;
542 int rc;
543
544 dev = kzalloc(sizeof(*dev), GFP_KERNEL);
545 if (!dev)
546 return -ENOMEM;
547
548 device_initialize(dev);
549
550 dev->class = power_supply_class;
551 dev->type = &power_supply_dev_type;
552 dev->parent = parent;
553 dev->release = power_supply_dev_release;
554 dev_set_drvdata(dev, psy);
555 psy->dev = dev;
556
557 rc = dev_set_name(dev, "%s", psy->name);
558 if (rc)
559 goto dev_set_name_failed;
560
561 INIT_WORK(&psy->changed_work, power_supply_changed_work);
562
563 rc = power_supply_check_supplies(psy);
564 if (rc) {
565 dev_info(dev, "Not all required supplies found, defer probe\n");
566 goto check_supplies_failed;
567 }
568
569 spin_lock_init(&psy->changed_lock);
570 rc = device_init_wakeup(dev, ws);
571 if (rc)
572 goto wakeup_init_failed;
573
574 rc = device_add(dev);
575 if (rc)
576 goto device_add_failed;
577
578 rc = psy_register_thermal(psy);
579 if (rc)
580 goto register_thermal_failed;
581
582 rc = psy_register_cooler(psy);
583 if (rc)
584 goto register_cooler_failed;
585
586 rc = power_supply_create_triggers(psy);
587 if (rc)
588 goto create_triggers_failed;
589
590 power_supply_changed(psy);
591
592 return 0;
593
594 create_triggers_failed:
595 psy_unregister_cooler(psy);
596 register_cooler_failed:
597 psy_unregister_thermal(psy);
598 register_thermal_failed:
599 device_del(dev);
600 device_add_failed:
601 wakeup_init_failed:
602 check_supplies_failed:
603 dev_set_name_failed:
604 put_device(dev);
605 return rc;
606 }
607
power_supply_register(struct device * parent,struct power_supply * psy)608 int power_supply_register(struct device *parent, struct power_supply *psy)
609 {
610 return __power_supply_register(parent, psy, true);
611 }
612 EXPORT_SYMBOL_GPL(power_supply_register);
613
power_supply_register_no_ws(struct device * parent,struct power_supply * psy)614 int power_supply_register_no_ws(struct device *parent, struct power_supply *psy)
615 {
616 return __power_supply_register(parent, psy, false);
617 }
618 EXPORT_SYMBOL_GPL(power_supply_register_no_ws);
619
power_supply_unregister(struct power_supply * psy)620 void power_supply_unregister(struct power_supply *psy)
621 {
622 cancel_work_sync(&psy->changed_work);
623 sysfs_remove_link(&psy->dev->kobj, "powers");
624 power_supply_remove_triggers(psy);
625 psy_unregister_cooler(psy);
626 psy_unregister_thermal(psy);
627 device_init_wakeup(psy->dev, false);
628 device_unregister(psy->dev);
629 }
630 EXPORT_SYMBOL_GPL(power_supply_unregister);
631
power_supply_class_init(void)632 static int __init power_supply_class_init(void)
633 {
634 power_supply_class = class_create(THIS_MODULE, "power_supply");
635
636 if (IS_ERR(power_supply_class))
637 return PTR_ERR(power_supply_class);
638
639 power_supply_class->dev_uevent = power_supply_uevent;
640 power_supply_init_attrs(&power_supply_dev_type);
641
642 return 0;
643 }
644
power_supply_class_exit(void)645 static void __exit power_supply_class_exit(void)
646 {
647 class_destroy(power_supply_class);
648 }
649
650 subsys_initcall(power_supply_class_init);
651 module_exit(power_supply_class_exit);
652
653 MODULE_DESCRIPTION("Universal power supply monitor class");
654 MODULE_AUTHOR("Ian Molton <spyro@f2s.com>, "
655 "Szabolcs Gyurko, "
656 "Anton Vorontsov <cbou@mail.ru>");
657 MODULE_LICENSE("GPL");
658