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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/err.h>
19#include <linux/power_supply.h>
20#include "power_supply.h"
21
22/* exported for the APM Power driver, APM emulation */
23struct class *power_supply_class;
24EXPORT_SYMBOL_GPL(power_supply_class);
25
26static struct device_type power_supply_dev_type;
27
28static int __power_supply_changed_work(struct device *dev, void *data)
29{
30 struct power_supply *psy = (struct power_supply *)data;
31 struct power_supply *pst = dev_get_drvdata(dev);
32 int i;
33
34 for (i = 0; i < psy->num_supplicants; i++)
35 if (!strcmp(psy->supplied_to[i], pst->name)) {
36 if (pst->external_power_changed)
37 pst->external_power_changed(pst);
38 }
39 return 0;
40}
41
42static void power_supply_changed_work(struct work_struct *work)
43{
44 struct power_supply *psy = container_of(work, struct power_supply,
45 changed_work);
46
47 dev_dbg(psy->dev, "%s\n", __func__);
48
49 class_for_each_device(power_supply_class, NULL, psy,
50 __power_supply_changed_work);
51
52 power_supply_update_leds(psy);
53
54 kobject_uevent(&psy->dev->kobj, KOBJ_CHANGE);
55}
56
57void power_supply_changed(struct power_supply *psy)
58{
59 dev_dbg(psy->dev, "%s\n", __func__);
60
61 schedule_work(&psy->changed_work);
62}
63EXPORT_SYMBOL_GPL(power_supply_changed);
64
65static int __power_supply_am_i_supplied(struct device *dev, void *data)
66{
67 union power_supply_propval ret = {0,};
68 struct power_supply *psy = (struct power_supply *)data;
69 struct power_supply *epsy = dev_get_drvdata(dev);
70 int i;
71
72 for (i = 0; i < epsy->num_supplicants; i++) {
73 if (!strcmp(epsy->supplied_to[i], psy->name)) {
74 if (epsy->get_property(epsy,
75 POWER_SUPPLY_PROP_ONLINE, &ret))
76 continue;
77 if (ret.intval)
78 return ret.intval;
79 }
80 }
81 return 0;
82}
83
84int power_supply_am_i_supplied(struct power_supply *psy)
85{
86 int error;
87
88 error = class_for_each_device(power_supply_class, NULL, psy,
89 __power_supply_am_i_supplied);
90
91 dev_dbg(psy->dev, "%s %d\n", __func__, error);
92
93 return error;
94}
95EXPORT_SYMBOL_GPL(power_supply_am_i_supplied);
96
97static int __power_supply_is_system_supplied(struct device *dev, void *data)
98{
99 union power_supply_propval ret = {0,};
100 struct power_supply *psy = dev_get_drvdata(dev);
101 unsigned int *count = data;
102
103 (*count)++;
104 if (psy->type != POWER_SUPPLY_TYPE_BATTERY) {
105 if (psy->get_property(psy, POWER_SUPPLY_PROP_ONLINE, &ret))
106 return 0;
107 if (ret.intval)
108 return ret.intval;
109 }
110 return 0;
111}
112
113int power_supply_is_system_supplied(void)
114{
115 int error;
116 unsigned int count = 0;
117
118 error = class_for_each_device(power_supply_class, NULL, &count,
119 __power_supply_is_system_supplied);
120
121 /*
122 * If no power class device was found at all, most probably we are
123 * running on a desktop system, so assume we are on mains power.
124 */
125 if (count == 0)
126 return 1;
127
128 return error;
129}
130EXPORT_SYMBOL_GPL(power_supply_is_system_supplied);
131
132int power_supply_set_battery_charged(struct power_supply *psy)
133{
134 if (psy->type == POWER_SUPPLY_TYPE_BATTERY && psy->set_charged) {
135 psy->set_charged(psy);
136 return 0;
137 }
138
139 return -EINVAL;
140}
141EXPORT_SYMBOL_GPL(power_supply_set_battery_charged);
142
143static int power_supply_match_device_by_name(struct device *dev, void *data)
144{
145 const char *name = data;
146 struct power_supply *psy = dev_get_drvdata(dev);
147
148 return strcmp(psy->name, name) == 0;
149}
150
151struct power_supply *power_supply_get_by_name(char *name)
152{
153 struct device *dev = class_find_device(power_supply_class, NULL, name,
154 power_supply_match_device_by_name);
155
156 return dev ? dev_get_drvdata(dev) : NULL;
157}
158EXPORT_SYMBOL_GPL(power_supply_get_by_name);
159
160int power_supply_powers(struct power_supply *psy, struct device *dev)
161{
162 return sysfs_create_link(&psy->dev->kobj, &dev->kobj, "powers");
163}
164EXPORT_SYMBOL_GPL(power_supply_powers);
165
166static void power_supply_dev_release(struct device *dev)
167{
168 pr_debug("device: '%s': %s\n", dev_name(dev), __func__);
169 kfree(dev);
170}
171
172int power_supply_register(struct device *parent, struct power_supply *psy)
173{
174 struct device *dev;
175 int rc;
176
177 dev = kzalloc(sizeof(*dev), GFP_KERNEL);
178 if (!dev)
179 return -ENOMEM;
180
181 device_initialize(dev);
182
183 dev->class = power_supply_class;
184 dev->type = &power_supply_dev_type;
185 dev->parent = parent;
186 dev->release = power_supply_dev_release;
187 dev_set_drvdata(dev, psy);
188 psy->dev = dev;
189
190 INIT_WORK(&psy->changed_work, power_supply_changed_work);
191
192 rc = kobject_set_name(&dev->kobj, "%s", psy->name);
193 if (rc)
194 goto kobject_set_name_failed;
195
196 rc = device_add(dev);
197 if (rc)
198 goto device_add_failed;
199
200 rc = power_supply_create_triggers(psy);
201 if (rc)
202 goto create_triggers_failed;
203
204 power_supply_changed(psy);
205
206 goto success;
207
208create_triggers_failed:
209 device_del(dev);
210kobject_set_name_failed:
211device_add_failed:
212 put_device(dev);
213success:
214 return rc;
215}
216EXPORT_SYMBOL_GPL(power_supply_register);
217
218void power_supply_unregister(struct power_supply *psy)
219{
220 cancel_work_sync(&psy->changed_work);
221 sysfs_remove_link(&psy->dev->kobj, "powers");
222 power_supply_remove_triggers(psy);
223 device_unregister(psy->dev);
224}
225EXPORT_SYMBOL_GPL(power_supply_unregister);
226
227static int __init power_supply_class_init(void)
228{
229 power_supply_class = class_create(THIS_MODULE, "power_supply");
230
231 if (IS_ERR(power_supply_class))
232 return PTR_ERR(power_supply_class);
233
234 power_supply_class->dev_uevent = power_supply_uevent;
235 power_supply_init_attrs(&power_supply_dev_type);
236
237 return 0;
238}
239
240static void __exit power_supply_class_exit(void)
241{
242 class_destroy(power_supply_class);
243}
244
245subsys_initcall(power_supply_class_init);
246module_exit(power_supply_class_exit);
247
248MODULE_DESCRIPTION("Universal power supply monitor class");
249MODULE_AUTHOR("Ian Molton <spyro@f2s.com>, "
250 "Szabolcs Gyurko, "
251 "Anton Vorontsov <cbou@mail.ru>");
252MODULE_LICENSE("GPL");