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/err.h>
19 #include <linux/power_supply.h>
20 #include <linux/thermal.h>
21 #include "power_supply.h"
23 /* exported for the APM Power driver, APM emulation */
24 struct class *power_supply_class;
25 EXPORT_SYMBOL_GPL(power_supply_class);
27 static struct device_type power_supply_dev_type;
29 static bool __power_supply_is_supplied_by(struct power_supply *supplier,
30 struct power_supply *supply)
34 if (!supply->supplied_from && !supplier->supplied_to)
37 /* Support both supplied_to and supplied_from modes */
38 if (supply->supplied_from) {
41 for (i = 0; i < supply->num_supplies; i++)
42 if (!strcmp(supplier->name, supply->supplied_from[i]))
47 for (i = 0; i < supplier->num_supplicants; i++)
48 if (!strcmp(supplier->supplied_to[i], supply->name))
55 static int __power_supply_changed_work(struct device *dev, void *data)
57 struct power_supply *psy = (struct power_supply *)data;
58 struct power_supply *pst = dev_get_drvdata(dev);
60 if (__power_supply_is_supplied_by(psy, pst)) {
61 if (pst->external_power_changed)
62 pst->external_power_changed(pst);
68 static void power_supply_changed_work(struct work_struct *work)
70 struct power_supply *psy = container_of(work, struct power_supply,
73 dev_dbg(psy->dev, "%s\n", __func__);
75 class_for_each_device(power_supply_class, NULL, psy,
76 __power_supply_changed_work);
78 power_supply_update_leds(psy);
80 kobject_uevent(&psy->dev->kobj, KOBJ_CHANGE);
83 void power_supply_changed(struct power_supply *psy)
85 dev_dbg(psy->dev, "%s\n", __func__);
87 schedule_work(&psy->changed_work);
89 EXPORT_SYMBOL_GPL(power_supply_changed);
94 static int __power_supply_populate_supplied_from(struct device *dev,
97 struct power_supply *psy = (struct power_supply *)data;
98 struct power_supply *epsy = dev_get_drvdata(dev);
99 struct device_node *np;
103 np = of_parse_phandle(psy->of_node, "power-supplies", i++);
107 if (np == epsy->of_node) {
108 dev_info(psy->dev, "%s: Found supply : %s\n",
109 psy->name, epsy->name);
110 psy->supplied_from[i-1] = (char *)epsy->name;
121 static int power_supply_populate_supplied_from(struct power_supply *psy)
125 error = class_for_each_device(power_supply_class, NULL, psy,
126 __power_supply_populate_supplied_from);
128 dev_dbg(psy->dev, "%s %d\n", __func__, error);
133 static int __power_supply_find_supply_from_node(struct device *dev,
136 struct device_node *np = (struct device_node *)data;
137 struct power_supply *epsy = dev_get_drvdata(dev);
139 /* return error breaks out of class_for_each_device loop */
140 if (epsy->of_node == np)
146 static int power_supply_find_supply_from_node(struct device_node *supply_node)
150 struct class_dev_iter iter;
153 * Use iterator to see if any other device is registered.
154 * This is required since class_for_each_device returns 0
155 * if there are no devices registered.
157 class_dev_iter_init(&iter, power_supply_class, NULL, NULL);
158 dev = class_dev_iter_next(&iter);
161 return -EPROBE_DEFER;
164 * We have to treat the return value as inverted, because if
165 * we return error on not found, then it won't continue looking.
166 * So we trick it by returning error on success to stop looking
167 * once the matching device is found.
169 error = class_for_each_device(power_supply_class, NULL, supply_node,
170 __power_supply_find_supply_from_node);
172 return error ? 0 : -EPROBE_DEFER;
175 static int power_supply_check_supplies(struct power_supply *psy)
177 struct device_node *np;
180 /* If there is already a list honor it */
181 if (psy->supplied_from && psy->num_supplies > 0)
184 /* No device node found, nothing to do */
191 np = of_parse_phandle(psy->of_node, "power-supplies", cnt++);
195 ret = power_supply_find_supply_from_node(np);
197 dev_dbg(psy->dev, "Failed to find supply, defer!\n");
199 return -EPROBE_DEFER;
204 /* All supplies found, allocate char ** array for filling */
205 psy->supplied_from = devm_kzalloc(psy->dev, sizeof(psy->supplied_from),
207 if (!psy->supplied_from) {
208 dev_err(psy->dev, "Couldn't allocate memory for supply list\n");
212 *psy->supplied_from = devm_kzalloc(psy->dev, sizeof(char *) * cnt,
214 if (!*psy->supplied_from) {
215 dev_err(psy->dev, "Couldn't allocate memory for supply list\n");
219 return power_supply_populate_supplied_from(psy);
222 static inline int power_supply_check_supplies(struct power_supply *psy)
228 static int __power_supply_am_i_supplied(struct device *dev, void *data)
230 union power_supply_propval ret = {0,};
231 struct power_supply *psy = (struct power_supply *)data;
232 struct power_supply *epsy = dev_get_drvdata(dev);
234 if (__power_supply_is_supplied_by(epsy, psy))
235 if (!epsy->get_property(epsy, POWER_SUPPLY_PROP_ONLINE, &ret)) {
243 int power_supply_am_i_supplied(struct power_supply *psy)
247 error = class_for_each_device(power_supply_class, NULL, psy,
248 __power_supply_am_i_supplied);
250 dev_dbg(psy->dev, "%s %d\n", __func__, error);
254 EXPORT_SYMBOL_GPL(power_supply_am_i_supplied);
256 static int __power_supply_is_system_supplied(struct device *dev, void *data)
258 union power_supply_propval ret = {0,};
259 struct power_supply *psy = dev_get_drvdata(dev);
260 unsigned int *count = data;
263 if (psy->type != POWER_SUPPLY_TYPE_BATTERY) {
264 if (psy->get_property(psy, POWER_SUPPLY_PROP_ONLINE, &ret))
272 int power_supply_is_system_supplied(void)
275 unsigned int count = 0;
277 error = class_for_each_device(power_supply_class, NULL, &count,
278 __power_supply_is_system_supplied);
281 * If no power class device was found at all, most probably we are
282 * running on a desktop system, so assume we are on mains power.
289 EXPORT_SYMBOL_GPL(power_supply_is_system_supplied);
291 int power_supply_set_battery_charged(struct power_supply *psy)
293 if (psy->type == POWER_SUPPLY_TYPE_BATTERY && psy->set_charged) {
294 psy->set_charged(psy);
300 EXPORT_SYMBOL_GPL(power_supply_set_battery_charged);
302 static int power_supply_match_device_by_name(struct device *dev, const void *data)
304 const char *name = data;
305 struct power_supply *psy = dev_get_drvdata(dev);
307 return strcmp(psy->name, name) == 0;
310 struct power_supply *power_supply_get_by_name(const char *name)
312 struct device *dev = class_find_device(power_supply_class, NULL, name,
313 power_supply_match_device_by_name);
315 return dev ? dev_get_drvdata(dev) : NULL;
317 EXPORT_SYMBOL_GPL(power_supply_get_by_name);
319 int power_supply_powers(struct power_supply *psy, struct device *dev)
321 return sysfs_create_link(&psy->dev->kobj, &dev->kobj, "powers");
323 EXPORT_SYMBOL_GPL(power_supply_powers);
325 static void power_supply_dev_release(struct device *dev)
327 pr_debug("device: '%s': %s\n", dev_name(dev), __func__);
331 #ifdef CONFIG_THERMAL
332 static int power_supply_read_temp(struct thermal_zone_device *tzd,
335 struct power_supply *psy;
336 union power_supply_propval val;
339 WARN_ON(tzd == NULL);
341 ret = psy->get_property(psy, POWER_SUPPLY_PROP_TEMP, &val);
343 /* Convert tenths of degree Celsius to milli degree Celsius. */
345 *temp = val.intval * 100;
350 static struct thermal_zone_device_ops psy_tzd_ops = {
351 .get_temp = power_supply_read_temp,
354 static int psy_register_thermal(struct power_supply *psy)
358 /* Register battery zone device psy reports temperature */
359 for (i = 0; i < psy->num_properties; i++) {
360 if (psy->properties[i] == POWER_SUPPLY_PROP_TEMP) {
361 psy->tzd = thermal_zone_device_register(psy->name, 0, 0,
362 psy, &psy_tzd_ops, NULL, 0, 0);
363 if (IS_ERR(psy->tzd))
364 return PTR_ERR(psy->tzd);
371 static void psy_unregister_thermal(struct power_supply *psy)
373 if (IS_ERR_OR_NULL(psy->tzd))
375 thermal_zone_device_unregister(psy->tzd);
378 /* thermal cooling device callbacks */
379 static int ps_get_max_charge_cntl_limit(struct thermal_cooling_device *tcd,
380 unsigned long *state)
382 struct power_supply *psy;
383 union power_supply_propval val;
387 ret = psy->get_property(psy,
388 POWER_SUPPLY_PROP_CHARGE_CONTROL_LIMIT_MAX, &val);
395 static int ps_get_cur_chrage_cntl_limit(struct thermal_cooling_device *tcd,
396 unsigned long *state)
398 struct power_supply *psy;
399 union power_supply_propval val;
403 ret = psy->get_property(psy,
404 POWER_SUPPLY_PROP_CHARGE_CONTROL_LIMIT, &val);
411 static int ps_set_cur_charge_cntl_limit(struct thermal_cooling_device *tcd,
414 struct power_supply *psy;
415 union power_supply_propval val;
420 ret = psy->set_property(psy,
421 POWER_SUPPLY_PROP_CHARGE_CONTROL_LIMIT, &val);
426 static struct thermal_cooling_device_ops psy_tcd_ops = {
427 .get_max_state = ps_get_max_charge_cntl_limit,
428 .get_cur_state = ps_get_cur_chrage_cntl_limit,
429 .set_cur_state = ps_set_cur_charge_cntl_limit,
432 static int psy_register_cooler(struct power_supply *psy)
436 /* Register for cooling device if psy can control charging */
437 for (i = 0; i < psy->num_properties; i++) {
438 if (psy->properties[i] ==
439 POWER_SUPPLY_PROP_CHARGE_CONTROL_LIMIT) {
440 psy->tcd = thermal_cooling_device_register(
443 if (IS_ERR(psy->tcd))
444 return PTR_ERR(psy->tcd);
451 static void psy_unregister_cooler(struct power_supply *psy)
453 if (IS_ERR_OR_NULL(psy->tcd))
455 thermal_cooling_device_unregister(psy->tcd);
458 static int psy_register_thermal(struct power_supply *psy)
463 static void psy_unregister_thermal(struct power_supply *psy)
467 static int psy_register_cooler(struct power_supply *psy)
472 static void psy_unregister_cooler(struct power_supply *psy)
477 int power_supply_register(struct device *parent, struct power_supply *psy)
482 dev = kzalloc(sizeof(*dev), GFP_KERNEL);
486 device_initialize(dev);
488 dev->class = power_supply_class;
489 dev->type = &power_supply_dev_type;
490 dev->parent = parent;
491 dev->release = power_supply_dev_release;
492 dev_set_drvdata(dev, psy);
495 INIT_WORK(&psy->changed_work, power_supply_changed_work);
497 rc = power_supply_check_supplies(psy);
499 dev_info(dev, "Not all required supplies found, defer probe\n");
500 goto check_supplies_failed;
503 rc = kobject_set_name(&dev->kobj, "%s", psy->name);
505 goto kobject_set_name_failed;
507 rc = device_add(dev);
509 goto device_add_failed;
511 rc = psy_register_thermal(psy);
513 goto register_thermal_failed;
515 rc = psy_register_cooler(psy);
517 goto register_cooler_failed;
519 rc = power_supply_create_triggers(psy);
521 goto create_triggers_failed;
523 power_supply_changed(psy);
527 create_triggers_failed:
528 psy_unregister_cooler(psy);
529 register_cooler_failed:
530 psy_unregister_thermal(psy);
531 register_thermal_failed:
533 kobject_set_name_failed:
535 check_supplies_failed:
540 EXPORT_SYMBOL_GPL(power_supply_register);
542 void power_supply_unregister(struct power_supply *psy)
544 cancel_work_sync(&psy->changed_work);
545 sysfs_remove_link(&psy->dev->kobj, "powers");
546 power_supply_remove_triggers(psy);
547 psy_unregister_cooler(psy);
548 psy_unregister_thermal(psy);
549 device_unregister(psy->dev);
551 EXPORT_SYMBOL_GPL(power_supply_unregister);
553 static int __init power_supply_class_init(void)
555 power_supply_class = class_create(THIS_MODULE, "power_supply");
557 if (IS_ERR(power_supply_class))
558 return PTR_ERR(power_supply_class);
560 power_supply_class->dev_uevent = power_supply_uevent;
561 power_supply_init_attrs(&power_supply_dev_type);
566 static void __exit power_supply_class_exit(void)
568 class_destroy(power_supply_class);
571 subsys_initcall(power_supply_class_init);
572 module_exit(power_supply_class_exit);
574 MODULE_DESCRIPTION("Universal power supply monitor class");
575 MODULE_AUTHOR("Ian Molton <spyro@f2s.com>, "
577 "Anton Vorontsov <cbou@mail.ru>");
578 MODULE_LICENSE("GPL");