2 * Universal power supply monitor class
4 * Copyright © 2007 Anton Vorontsov <cbou@mail.ru>
5 * Copyright © 2004 Szabolcs Gyurko
6 * Copyright © 2003 Ian Molton <spyro@f2s.com>
8 * Modified: 2004, Oct Szabolcs Gyurko
10 * You may use this code as per GPL version 2
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"
24 /* exported for the APM Power driver, APM emulation */
25 struct class *power_supply_class;
26 EXPORT_SYMBOL_GPL(power_supply_class);
28 ATOMIC_NOTIFIER_HEAD(power_supply_notifier);
29 EXPORT_SYMBOL_GPL(power_supply_notifier);
31 static struct device_type power_supply_dev_type;
33 static bool __power_supply_is_supplied_by(struct power_supply *supplier,
34 struct power_supply *supply)
38 if (!supply->supplied_from && !supplier->supplied_to)
41 /* Support both supplied_to and supplied_from modes */
42 if (supply->supplied_from) {
45 for (i = 0; i < supply->num_supplies; i++)
46 if (!strcmp(supplier->name, supply->supplied_from[i]))
51 for (i = 0; i < supplier->num_supplicants; i++)
52 if (!strcmp(supplier->supplied_to[i], supply->name))
59 static int __power_supply_changed_work(struct device *dev, void *data)
61 struct power_supply *psy = data;
62 struct power_supply *pst = dev_get_drvdata(dev);
64 if (__power_supply_is_supplied_by(psy, pst)) {
65 if (pst->external_power_changed)
66 pst->external_power_changed(pst);
72 static void power_supply_changed_work(struct work_struct *work)
75 struct power_supply *psy = container_of(work, struct power_supply,
78 dev_dbg(psy->dev, "%s\n", __func__);
80 spin_lock_irqsave(&psy->changed_lock, flags);
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.
88 if (likely(psy->changed)) {
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);
101 * Hold the wakeup_source until all events are processed.
102 * power_supply_changed() might have called again and have set 'changed'
105 if (likely(!psy->changed))
107 spin_unlock_irqrestore(&psy->changed_lock, flags);
110 void power_supply_changed(struct power_supply *psy)
114 dev_dbg(psy->dev, "%s\n", __func__);
116 spin_lock_irqsave(&psy->changed_lock, flags);
118 pm_stay_awake(psy->dev);
119 spin_unlock_irqrestore(&psy->changed_lock, flags);
120 schedule_work(&psy->changed_work);
122 EXPORT_SYMBOL_GPL(power_supply_changed);
125 #include <linux/of.h>
127 static int __power_supply_populate_supplied_from(struct device *dev,
130 struct power_supply *psy = data;
131 struct power_supply *epsy = dev_get_drvdata(dev);
132 struct device_node *np;
136 np = of_parse_phandle(psy->of_node, "power-supplies", i++);
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;
154 static int power_supply_populate_supplied_from(struct power_supply *psy)
158 error = class_for_each_device(power_supply_class, NULL, psy,
159 __power_supply_populate_supplied_from);
161 dev_dbg(psy->dev, "%s %d\n", __func__, error);
166 static int __power_supply_find_supply_from_node(struct device *dev,
169 struct device_node *np = data;
170 struct power_supply *epsy = dev_get_drvdata(dev);
172 /* returning non-zero breaks out of class_for_each_device loop */
173 if (epsy->of_node == np)
179 static int power_supply_find_supply_from_node(struct device_node *supply_node)
183 struct class_dev_iter iter;
186 * Use iterator to see if any other device is registered.
187 * This is required since class_for_each_device returns 0
188 * if there are no devices registered.
190 class_dev_iter_init(&iter, power_supply_class, NULL, NULL);
191 dev = class_dev_iter_next(&iter);
194 return -EPROBE_DEFER;
197 * class_for_each_device() either returns its own errors or values
198 * returned by __power_supply_find_supply_from_node().
200 * __power_supply_find_supply_from_node() will return 0 (no match)
203 * We return 0 if class_for_each_device() returned 1, -EPROBE_DEFER if
204 * it returned 0, or error as returned by it.
206 error = class_for_each_device(power_supply_class, NULL, supply_node,
207 __power_supply_find_supply_from_node);
209 return error ? (error == 1 ? 0 : error) : -EPROBE_DEFER;
212 static int power_supply_check_supplies(struct power_supply *psy)
214 struct device_node *np;
217 /* If there is already a list honor it */
218 if (psy->supplied_from && psy->num_supplies > 0)
221 /* No device node found, nothing to do */
228 np = of_parse_phandle(psy->of_node, "power-supplies", cnt++);
232 ret = power_supply_find_supply_from_node(np);
236 dev_dbg(psy->dev, "Failed to find supply!\n");
241 /* Missing valid "power-supplies" entries */
245 /* All supplies found, allocate char ** array for filling */
246 psy->supplied_from = devm_kzalloc(psy->dev, sizeof(psy->supplied_from),
248 if (!psy->supplied_from) {
249 dev_err(psy->dev, "Couldn't allocate memory for supply list\n");
253 *psy->supplied_from = devm_kzalloc(psy->dev, sizeof(char *) * (cnt - 1),
255 if (!*psy->supplied_from) {
256 dev_err(psy->dev, "Couldn't allocate memory for supply list\n");
260 return power_supply_populate_supplied_from(psy);
263 static inline int power_supply_check_supplies(struct power_supply *psy)
269 static int __power_supply_am_i_supplied(struct device *dev, void *data)
271 union power_supply_propval ret = {0,};
272 struct power_supply *psy = data;
273 struct power_supply *epsy = dev_get_drvdata(dev);
275 if (__power_supply_is_supplied_by(epsy, psy))
276 if (!epsy->get_property(epsy, POWER_SUPPLY_PROP_ONLINE, &ret))
282 int power_supply_am_i_supplied(struct power_supply *psy)
286 error = class_for_each_device(power_supply_class, NULL, psy,
287 __power_supply_am_i_supplied);
289 dev_dbg(psy->dev, "%s %d\n", __func__, error);
293 EXPORT_SYMBOL_GPL(power_supply_am_i_supplied);
295 static int __power_supply_is_system_supplied(struct device *dev, void *data)
297 union power_supply_propval ret = {0,};
298 struct power_supply *psy = dev_get_drvdata(dev);
299 unsigned int *count = data;
302 if (psy->type != POWER_SUPPLY_TYPE_BATTERY)
303 if (!psy->get_property(psy, POWER_SUPPLY_PROP_ONLINE, &ret))
309 int power_supply_is_system_supplied(void)
312 unsigned int count = 0;
314 error = class_for_each_device(power_supply_class, NULL, &count,
315 __power_supply_is_system_supplied);
318 * If no power class device was found at all, most probably we are
319 * running on a desktop system, so assume we are on mains power.
326 EXPORT_SYMBOL_GPL(power_supply_is_system_supplied);
328 int power_supply_set_battery_charged(struct power_supply *psy)
330 if (psy->type == POWER_SUPPLY_TYPE_BATTERY && psy->set_charged) {
331 psy->set_charged(psy);
337 EXPORT_SYMBOL_GPL(power_supply_set_battery_charged);
339 static int power_supply_match_device_by_name(struct device *dev, const void *data)
341 const char *name = data;
342 struct power_supply *psy = dev_get_drvdata(dev);
344 return strcmp(psy->name, name) == 0;
347 struct power_supply *power_supply_get_by_name(const char *name)
349 struct device *dev = class_find_device(power_supply_class, NULL, name,
350 power_supply_match_device_by_name);
352 return dev ? dev_get_drvdata(dev) : NULL;
354 EXPORT_SYMBOL_GPL(power_supply_get_by_name);
357 static int power_supply_match_device_node(struct device *dev, const void *data)
359 return dev->parent && dev->parent->of_node == data;
362 struct power_supply *power_supply_get_by_phandle(struct device_node *np,
363 const char *property)
365 struct device_node *power_supply_np;
368 power_supply_np = of_parse_phandle(np, property, 0);
369 if (!power_supply_np)
370 return ERR_PTR(-ENODEV);
372 dev = class_find_device(power_supply_class, NULL, power_supply_np,
373 power_supply_match_device_node);
375 of_node_put(power_supply_np);
377 return dev ? dev_get_drvdata(dev) : NULL;
379 EXPORT_SYMBOL_GPL(power_supply_get_by_phandle);
380 #endif /* CONFIG_OF */
382 int power_supply_powers(struct power_supply *psy, struct device *dev)
384 return sysfs_create_link(&psy->dev->kobj, &dev->kobj, "powers");
386 EXPORT_SYMBOL_GPL(power_supply_powers);
388 static void power_supply_dev_release(struct device *dev)
390 pr_debug("device: '%s': %s\n", dev_name(dev), __func__);
394 int power_supply_reg_notifier(struct notifier_block *nb)
396 return atomic_notifier_chain_register(&power_supply_notifier, nb);
398 EXPORT_SYMBOL_GPL(power_supply_reg_notifier);
400 void power_supply_unreg_notifier(struct notifier_block *nb)
402 atomic_notifier_chain_unregister(&power_supply_notifier, nb);
404 EXPORT_SYMBOL_GPL(power_supply_unreg_notifier);
406 #ifdef CONFIG_THERMAL
407 static int power_supply_read_temp(struct thermal_zone_device *tzd,
410 struct power_supply *psy;
411 union power_supply_propval val;
414 WARN_ON(tzd == NULL);
416 ret = psy->get_property(psy, POWER_SUPPLY_PROP_TEMP, &val);
418 /* Convert tenths of degree Celsius to milli degree Celsius. */
420 *temp = val.intval * 100;
425 static struct thermal_zone_device_ops psy_tzd_ops = {
426 .get_temp = power_supply_read_temp,
429 static int psy_register_thermal(struct power_supply *psy)
433 /* Register battery zone device psy reports temperature */
434 for (i = 0; i < psy->num_properties; i++) {
435 if (psy->properties[i] == POWER_SUPPLY_PROP_TEMP) {
436 psy->tzd = thermal_zone_device_register(psy->name, 0, 0,
437 psy, &psy_tzd_ops, NULL, 0, 0);
438 return PTR_ERR_OR_ZERO(psy->tzd);
444 static void psy_unregister_thermal(struct power_supply *psy)
446 if (IS_ERR_OR_NULL(psy->tzd))
448 thermal_zone_device_unregister(psy->tzd);
451 /* thermal cooling device callbacks */
452 static int ps_get_max_charge_cntl_limit(struct thermal_cooling_device *tcd,
453 unsigned long *state)
455 struct power_supply *psy;
456 union power_supply_propval val;
460 ret = psy->get_property(psy,
461 POWER_SUPPLY_PROP_CHARGE_CONTROL_LIMIT_MAX, &val);
468 static int ps_get_cur_chrage_cntl_limit(struct thermal_cooling_device *tcd,
469 unsigned long *state)
471 struct power_supply *psy;
472 union power_supply_propval val;
476 ret = psy->get_property(psy,
477 POWER_SUPPLY_PROP_CHARGE_CONTROL_LIMIT, &val);
484 static int ps_set_cur_charge_cntl_limit(struct thermal_cooling_device *tcd,
487 struct power_supply *psy;
488 union power_supply_propval val;
493 ret = psy->set_property(psy,
494 POWER_SUPPLY_PROP_CHARGE_CONTROL_LIMIT, &val);
499 static struct thermal_cooling_device_ops psy_tcd_ops = {
500 .get_max_state = ps_get_max_charge_cntl_limit,
501 .get_cur_state = ps_get_cur_chrage_cntl_limit,
502 .set_cur_state = ps_set_cur_charge_cntl_limit,
505 static int psy_register_cooler(struct power_supply *psy)
509 /* Register for cooling device if psy can control charging */
510 for (i = 0; i < psy->num_properties; i++) {
511 if (psy->properties[i] ==
512 POWER_SUPPLY_PROP_CHARGE_CONTROL_LIMIT) {
513 psy->tcd = thermal_cooling_device_register(
516 return PTR_ERR_OR_ZERO(psy->tcd);
522 static void psy_unregister_cooler(struct power_supply *psy)
524 if (IS_ERR_OR_NULL(psy->tcd))
526 thermal_cooling_device_unregister(psy->tcd);
529 static int psy_register_thermal(struct power_supply *psy)
534 static void psy_unregister_thermal(struct power_supply *psy)
538 static int psy_register_cooler(struct power_supply *psy)
543 static void psy_unregister_cooler(struct power_supply *psy)
548 static int __power_supply_register(struct device *parent,
549 struct power_supply *psy, bool ws)
554 dev = kzalloc(sizeof(*dev), GFP_KERNEL);
558 device_initialize(dev);
560 dev->class = power_supply_class;
561 dev->type = &power_supply_dev_type;
562 dev->parent = parent;
563 dev->release = power_supply_dev_release;
564 dev_set_drvdata(dev, psy);
567 rc = dev_set_name(dev, "%s", psy->name);
569 goto dev_set_name_failed;
571 INIT_WORK(&psy->changed_work, power_supply_changed_work);
573 rc = power_supply_check_supplies(psy);
575 dev_info(dev, "Not all required supplies found, defer probe\n");
576 goto check_supplies_failed;
579 spin_lock_init(&psy->changed_lock);
580 rc = device_init_wakeup(dev, ws);
582 goto wakeup_init_failed;
584 rc = device_add(dev);
586 goto device_add_failed;
588 rc = psy_register_thermal(psy);
590 goto register_thermal_failed;
592 rc = psy_register_cooler(psy);
594 goto register_cooler_failed;
596 rc = power_supply_create_triggers(psy);
598 goto create_triggers_failed;
600 power_supply_changed(psy);
604 create_triggers_failed:
605 psy_unregister_cooler(psy);
606 register_cooler_failed:
607 psy_unregister_thermal(psy);
608 register_thermal_failed:
612 check_supplies_failed:
618 int power_supply_register(struct device *parent, struct power_supply *psy)
620 return __power_supply_register(parent, psy, true);
622 EXPORT_SYMBOL_GPL(power_supply_register);
624 int power_supply_register_no_ws(struct device *parent, struct power_supply *psy)
626 return __power_supply_register(parent, psy, false);
628 EXPORT_SYMBOL_GPL(power_supply_register_no_ws);
630 void power_supply_unregister(struct power_supply *psy)
632 cancel_work_sync(&psy->changed_work);
633 sysfs_remove_link(&psy->dev->kobj, "powers");
634 power_supply_remove_triggers(psy);
635 psy_unregister_cooler(psy);
636 psy_unregister_thermal(psy);
637 device_init_wakeup(psy->dev, false);
638 device_unregister(psy->dev);
640 EXPORT_SYMBOL_GPL(power_supply_unregister);
642 static int __init power_supply_class_init(void)
644 power_supply_class = class_create(THIS_MODULE, "power_supply");
646 if (IS_ERR(power_supply_class))
647 return PTR_ERR(power_supply_class);
649 power_supply_class->dev_uevent = power_supply_uevent;
650 power_supply_init_attrs(&power_supply_dev_type);
655 static void __exit power_supply_class_exit(void)
657 class_destroy(power_supply_class);
660 subsys_initcall(power_supply_class_init);
661 module_exit(power_supply_class_exit);
663 MODULE_DESCRIPTION("Universal power supply monitor class");
664 MODULE_AUTHOR("Ian Molton <spyro@f2s.com>, "
666 "Anton Vorontsov <cbou@mail.ru>");
667 MODULE_LICENSE("GPL");