Power supply class and drivers: remove non obligatory return statements
[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 struct class *power_supply_class;
22
23 static void power_supply_changed_work(struct work_struct *work)
24 {
25         struct power_supply *psy = container_of(work, struct power_supply,
26                                                 changed_work);
27         int i;
28
29         dev_dbg(psy->dev, "%s\n", __FUNCTION__);
30
31         for (i = 0; i < psy->num_supplicants; i++) {
32                 struct device *dev;
33
34                 down(&power_supply_class->sem);
35                 list_for_each_entry(dev, &power_supply_class->devices, node) {
36                         struct power_supply *pst = dev_get_drvdata(dev);
37
38                         if (!strcmp(psy->supplied_to[i], pst->name)) {
39                                 if (pst->external_power_changed)
40                                         pst->external_power_changed(pst);
41                         }
42                 }
43                 up(&power_supply_class->sem);
44         }
45
46         power_supply_update_leds(psy);
47
48         kobject_uevent(&psy->dev->kobj, KOBJ_CHANGE);
49 }
50
51 void power_supply_changed(struct power_supply *psy)
52 {
53         dev_dbg(psy->dev, "%s\n", __FUNCTION__);
54
55         schedule_work(&psy->changed_work);
56 }
57
58 int power_supply_am_i_supplied(struct power_supply *psy)
59 {
60         union power_supply_propval ret = {0,};
61         struct device *dev;
62
63         down(&power_supply_class->sem);
64         list_for_each_entry(dev, &power_supply_class->devices, node) {
65                 struct power_supply *epsy = dev_get_drvdata(dev);
66                 int i;
67
68                 for (i = 0; i < epsy->num_supplicants; i++) {
69                         if (!strcmp(epsy->supplied_to[i], psy->name)) {
70                                 if (epsy->get_property(epsy,
71                                           POWER_SUPPLY_PROP_ONLINE, &ret))
72                                         continue;
73                                 if (ret.intval)
74                                         goto out;
75                         }
76                 }
77         }
78 out:
79         up(&power_supply_class->sem);
80
81         dev_dbg(psy->dev, "%s %d\n", __FUNCTION__, ret.intval);
82
83         return ret.intval;
84 }
85
86 int power_supply_register(struct device *parent, struct power_supply *psy)
87 {
88         int rc = 0;
89
90         psy->dev = device_create(power_supply_class, parent, 0,
91                                  "%s", psy->name);
92         if (IS_ERR(psy->dev)) {
93                 rc = PTR_ERR(psy->dev);
94                 goto dev_create_failed;
95         }
96
97         dev_set_drvdata(psy->dev, psy);
98
99         INIT_WORK(&psy->changed_work, power_supply_changed_work);
100
101         rc = power_supply_create_attrs(psy);
102         if (rc)
103                 goto create_attrs_failed;
104
105         rc = power_supply_create_triggers(psy);
106         if (rc)
107                 goto create_triggers_failed;
108
109         power_supply_changed(psy);
110
111         goto success;
112
113 create_triggers_failed:
114         power_supply_remove_attrs(psy);
115 create_attrs_failed:
116         device_unregister(psy->dev);
117 dev_create_failed:
118 success:
119         return rc;
120 }
121
122 void power_supply_unregister(struct power_supply *psy)
123 {
124         flush_scheduled_work();
125         power_supply_remove_triggers(psy);
126         power_supply_remove_attrs(psy);
127         device_unregister(psy->dev);
128 }
129
130 static int __init power_supply_class_init(void)
131 {
132         power_supply_class = class_create(THIS_MODULE, "power_supply");
133
134         if (IS_ERR(power_supply_class))
135                 return PTR_ERR(power_supply_class);
136
137         power_supply_class->dev_uevent = power_supply_uevent;
138
139         return 0;
140 }
141
142 static void __exit power_supply_class_exit(void)
143 {
144         class_destroy(power_supply_class);
145 }
146
147 EXPORT_SYMBOL_GPL(power_supply_changed);
148 EXPORT_SYMBOL_GPL(power_supply_am_i_supplied);
149 EXPORT_SYMBOL_GPL(power_supply_register);
150 EXPORT_SYMBOL_GPL(power_supply_unregister);
151
152 /* exported for the APM Power driver, APM emulation */
153 EXPORT_SYMBOL_GPL(power_supply_class);
154
155 subsys_initcall(power_supply_class_init);
156 module_exit(power_supply_class_exit);
157
158 MODULE_DESCRIPTION("Universal power supply monitor class");
159 MODULE_AUTHOR("Ian Molton <spyro@f2s.com>, "
160               "Szabolcs Gyurko, "
161               "Anton Vorontsov <cbou@mail.ru>");
162 MODULE_LICENSE("GPL");