Merge git://git.kernel.org/pub/scm/linux/kernel/git/davem/sparc-2.6
[linux-2.6.git] / drivers / power / power_supply_core.c
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/device.h>
17 #include <linux/err.h>
18 #include <linux/power_supply.h>
19 #include "power_supply.h"
20
21 /* exported for the APM Power driver, APM emulation */
22 struct class *power_supply_class;
23 EXPORT_SYMBOL_GPL(power_supply_class);
24
25 static int __power_supply_changed_work(struct device *dev, void *data)
26 {
27         struct power_supply *psy = (struct power_supply *)data;
28         struct power_supply *pst = dev_get_drvdata(dev);
29         int i;
30
31         for (i = 0; i < psy->num_supplicants; i++)
32                 if (!strcmp(psy->supplied_to[i], pst->name)) {
33                         if (pst->external_power_changed)
34                                 pst->external_power_changed(pst);
35                 }
36         return 0;
37 }
38
39 static void power_supply_changed_work(struct work_struct *work)
40 {
41         struct power_supply *psy = container_of(work, struct power_supply,
42                                                 changed_work);
43
44         dev_dbg(psy->dev, "%s\n", __func__);
45
46         class_for_each_device(power_supply_class, NULL, psy,
47                               __power_supply_changed_work);
48
49         power_supply_update_leds(psy);
50
51         kobject_uevent(&psy->dev->kobj, KOBJ_CHANGE);
52 }
53
54 void power_supply_changed(struct power_supply *psy)
55 {
56         dev_dbg(psy->dev, "%s\n", __func__);
57
58         schedule_work(&psy->changed_work);
59 }
60 EXPORT_SYMBOL_GPL(power_supply_changed);
61
62 static int __power_supply_am_i_supplied(struct device *dev, void *data)
63 {
64         union power_supply_propval ret = {0,};
65         struct power_supply *psy = (struct power_supply *)data;
66         struct power_supply *epsy = dev_get_drvdata(dev);
67         int i;
68
69         for (i = 0; i < epsy->num_supplicants; i++) {
70                 if (!strcmp(epsy->supplied_to[i], psy->name)) {
71                         if (epsy->get_property(epsy,
72                                   POWER_SUPPLY_PROP_ONLINE, &ret))
73                                 continue;
74                         if (ret.intval)
75                                 return ret.intval;
76                 }
77         }
78         return 0;
79 }
80
81 int power_supply_am_i_supplied(struct power_supply *psy)
82 {
83         int error;
84
85         error = class_for_each_device(power_supply_class, NULL, psy,
86                                       __power_supply_am_i_supplied);
87
88         dev_dbg(psy->dev, "%s %d\n", __func__, error);
89
90         return error;
91 }
92 EXPORT_SYMBOL_GPL(power_supply_am_i_supplied);
93
94 static int __power_supply_is_system_supplied(struct device *dev, void *data)
95 {
96         union power_supply_propval ret = {0,};
97         struct power_supply *psy = dev_get_drvdata(dev);
98
99         if (psy->type != POWER_SUPPLY_TYPE_BATTERY) {
100                 if (psy->get_property(psy, POWER_SUPPLY_PROP_ONLINE, &ret))
101                         return 0;
102                 if (ret.intval)
103                         return ret.intval;
104         }
105         return 0;
106 }
107
108 int power_supply_is_system_supplied(void)
109 {
110         int error;
111
112         error = class_for_each_device(power_supply_class, NULL, NULL,
113                                       __power_supply_is_system_supplied);
114
115         return error;
116 }
117 EXPORT_SYMBOL_GPL(power_supply_is_system_supplied);
118
119 int power_supply_set_battery_charged(struct power_supply *psy)
120 {
121         if (psy->type == POWER_SUPPLY_TYPE_BATTERY && psy->set_charged) {
122                 psy->set_charged(psy);
123                 return 0;
124         }
125
126         return -EINVAL;
127 }
128 EXPORT_SYMBOL_GPL(power_supply_set_battery_charged);
129
130 static int power_supply_match_device_by_name(struct device *dev, void *data)
131 {
132         const char *name = data;
133         struct power_supply *psy = dev_get_drvdata(dev);
134
135         return strcmp(psy->name, name) == 0;
136 }
137
138 struct power_supply *power_supply_get_by_name(char *name)
139 {
140         struct device *dev = class_find_device(power_supply_class, NULL, name,
141                                         power_supply_match_device_by_name);
142
143         return dev ? dev_get_drvdata(dev) : NULL;
144 }
145 EXPORT_SYMBOL_GPL(power_supply_get_by_name);
146
147 int power_supply_register(struct device *parent, struct power_supply *psy)
148 {
149         int rc = 0;
150
151         psy->dev = device_create(power_supply_class, parent, 0, psy,
152                                  "%s", psy->name);
153         if (IS_ERR(psy->dev)) {
154                 rc = PTR_ERR(psy->dev);
155                 goto dev_create_failed;
156         }
157
158         INIT_WORK(&psy->changed_work, power_supply_changed_work);
159
160         rc = power_supply_create_attrs(psy);
161         if (rc)
162                 goto create_attrs_failed;
163
164         rc = power_supply_create_triggers(psy);
165         if (rc)
166                 goto create_triggers_failed;
167
168         power_supply_changed(psy);
169
170         goto success;
171
172 create_triggers_failed:
173         power_supply_remove_attrs(psy);
174 create_attrs_failed:
175         device_unregister(psy->dev);
176 dev_create_failed:
177 success:
178         return rc;
179 }
180 EXPORT_SYMBOL_GPL(power_supply_register);
181
182 void power_supply_unregister(struct power_supply *psy)
183 {
184         flush_scheduled_work();
185         power_supply_remove_triggers(psy);
186         power_supply_remove_attrs(psy);
187         device_unregister(psy->dev);
188 }
189 EXPORT_SYMBOL_GPL(power_supply_unregister);
190
191 static int __init power_supply_class_init(void)
192 {
193         power_supply_class = class_create(THIS_MODULE, "power_supply");
194
195         if (IS_ERR(power_supply_class))
196                 return PTR_ERR(power_supply_class);
197
198         power_supply_class->dev_uevent = power_supply_uevent;
199
200         return 0;
201 }
202
203 static void __exit power_supply_class_exit(void)
204 {
205         class_destroy(power_supply_class);
206 }
207
208 subsys_initcall(power_supply_class_init);
209 module_exit(power_supply_class_exit);
210
211 MODULE_DESCRIPTION("Universal power supply monitor class");
212 MODULE_AUTHOR("Ian Molton <spyro@f2s.com>, "
213               "Szabolcs Gyurko, "
214               "Anton Vorontsov <cbou@mail.ru>");
215 MODULE_LICENSE("GPL");