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/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 #ifdef CONFIG_POWER_ON_CHARGER_DISPLAY
  23 extern struct list_head rk_psy_head;
  24 #endif
  25 /* exported for the APM Power driver, APM emulation */
  26 struct class *power_supply_class;
  27 EXPORT_SYMBOL_GPL(power_supply_class);
  28
  29 static struct device_type power_supply_dev_type;
  30
  31 static int __power_supply_changed_work(struct device *dev, void *data)
  32 {
  33         struct power_supply *psy = (struct power_supply *)data;
  34         struct power_supply *pst = dev_get_drvdata(dev);
  35         int i;
  36
  37         for (i = 0; i < psy->num_supplicants; i++)
  38                 if (!strcmp(psy->supplied_to[i], pst->name)) {
  39                         if (pst->external_power_changed)
  40                                 pst->external_power_changed(pst);
  41                 }
  42         return 0;
  43 }
  44
  45 static void power_supply_changed_work(struct work_struct *work)
  46 {
  47         unsigned long flags;
  48         struct power_supply *psy = container_of(work, struct power_supply,
  49                                                 changed_work);
  50
  51         dev_dbg(psy->dev, "%s\n", __func__);
  52
  53         spin_lock_irqsave(&psy->changed_lock, flags);
  54         if (psy->changed) {
  55                 psy->changed = false;
  56                 spin_unlock_irqrestore(&psy->changed_lock, flags);
  57
  58                 class_for_each_device(power_supply_class, NULL, psy,
  59                                       __power_supply_changed_work);
  60
  61                 power_supply_update_leds(psy);
  62
  63                 kobject_uevent(&psy->dev->kobj, KOBJ_CHANGE);
  64                 spin_lock_irqsave(&psy->changed_lock, flags);
  65         }
  66         if (!psy->changed)
  67                 wake_unlock(&psy->work_wake_lock);
  68         spin_unlock_irqrestore(&psy->changed_lock, flags);
  69 }
  70
  71 void power_supply_changed(struct power_supply *psy)
  72 {
  73         unsigned long flags;
  74
  75         dev_dbg(psy->dev, "%s\n", __func__);
  76
  77         spin_lock_irqsave(&psy->changed_lock, flags);
  78         psy->changed = true;
  79         wake_lock(&psy->work_wake_lock);
  80         spin_unlock_irqrestore(&psy->changed_lock, flags);
  81         schedule_work(&psy->changed_work);
  82 }
  83 EXPORT_SYMBOL_GPL(power_supply_changed);
  84
  85 static int __power_supply_am_i_supplied(struct device *dev, void *data)
  86 {
  87         union power_supply_propval ret = {0,};
  88         struct power_supply *psy = (struct power_supply *)data;
  89         struct power_supply *epsy = dev_get_drvdata(dev);
  90         int i;
  91
  92         for (i = 0; i < epsy->num_supplicants; i++) {
  93                 if (!strcmp(epsy->supplied_to[i], psy->name)) {
  94                         if (epsy->get_property(epsy,
  95                                   POWER_SUPPLY_PROP_ONLINE, &ret))
  96                                 continue;
  97                         if (ret.intval)
  98                                 return ret.intval;
  99                 }
 100         }
 101         return 0;
 102 }
 103
 104 int power_supply_am_i_supplied(struct power_supply *psy)
 105 {
 106         int error;
 107
 108         error = class_for_each_device(power_supply_class, NULL, psy,
 109                                       __power_supply_am_i_supplied);
 110
 111         dev_dbg(psy->dev, "%s %d\n", __func__, error);
 112
 113         return error;
 114 }
 115 EXPORT_SYMBOL_GPL(power_supply_am_i_supplied);
 116
 117 static int __power_supply_is_system_supplied(struct device *dev, void *data)
 118 {
 119         union power_supply_propval ret = {0,};
 120         struct power_supply *psy = dev_get_drvdata(dev);
 121
 122         if (psy->type != POWER_SUPPLY_TYPE_BATTERY) {
 123                 if (psy->get_property(psy, POWER_SUPPLY_PROP_ONLINE, &ret))
 124                         return 0;
 125                 if (ret.intval)
 126                         return ret.intval;
 127         }
 128         return 0;
 129 }
 130
 131 int power_supply_is_system_supplied(void)
 132 {
 133         int error;
 134
 135         error = class_for_each_device(power_supply_class, NULL, NULL,
 136                                       __power_supply_is_system_supplied);
 137
 138         return error;
 139 }
 140 EXPORT_SYMBOL_GPL(power_supply_is_system_supplied);
 141
 142 int power_supply_set_battery_charged(struct power_supply *psy)
 143 {
 144         if (psy->type == POWER_SUPPLY_TYPE_BATTERY && psy->set_charged) {
 145                 psy->set_charged(psy);
 146                 return 0;
 147         }
 148
 149         return -EINVAL;
 150 }
 151 EXPORT_SYMBOL_GPL(power_supply_set_battery_charged);
 152
 153 static int power_supply_match_device_by_name(struct device *dev, void *data)
 154 {
 155         const char *name = data;
 156         struct power_supply *psy = dev_get_drvdata(dev);
 157
 158         return strcmp(psy->name, name) == 0;
 159 }
 160
 161 struct power_supply *power_supply_get_by_name(char *name)
 162 {
 163         struct device *dev = class_find_device(power_supply_class, NULL, name,
 164                                         power_supply_match_device_by_name);
 165
 166         return dev ? dev_get_drvdata(dev) : NULL;
 167 }
 168 EXPORT_SYMBOL_GPL(power_supply_get_by_name);
 169
 170 static void power_supply_dev_release(struct device *dev)
 171 {
 172         pr_debug("device: '%s': %s\n", dev_name(dev), __func__);
 173         kfree(dev);
 174 }
 175
 176 int power_supply_register(struct device *parent, struct power_supply *psy)
 177 {
 178         struct device *dev;
 179         int rc;
 180
 181         dev = kzalloc(sizeof(*dev), GFP_KERNEL);
 182         if (!dev)
 183                 return -ENOMEM;
 184
 185         device_initialize(dev);
 186
 187 #ifdef CONFIG_POWER_ON_CHARGER_DISPLAY
 188         list_add(&psy->rk_psy_node, &rk_psy_head);
 189 #endif
 190
 191         dev->class = power_supply_class;
 192         dev->type = &power_supply_dev_type;
 193         dev->parent = parent;
 194         dev->release = power_supply_dev_release;
 195         dev_set_drvdata(dev, psy);
 196         psy->dev = dev;
 197
 198         INIT_WORK(&psy->changed_work, power_supply_changed_work);
 199
 200         rc = kobject_set_name(&dev->kobj, "%s", psy->name);
 201         if (rc)
 202                 goto kobject_set_name_failed;
 203
 204         rc = device_add(dev);
 205         if (rc)
 206                 goto device_add_failed;
 207
 208         spin_lock_init(&psy->changed_lock);
 209         wake_lock_init(&psy->work_wake_lock, WAKE_LOCK_SUSPEND, "power-supply");
 210
 211         rc = power_supply_create_triggers(psy);
 212         if (rc)
 213                 goto create_triggers_failed;
 214
 215         power_supply_changed(psy);
 216
 217         goto success;
 218
 219 create_triggers_failed:
 220         wake_lock_destroy(&psy->work_wake_lock);
 221         device_del(dev);
 222 kobject_set_name_failed:
 223 device_add_failed:
 224         put_device(dev);
 225 success:
 226         return rc;
 227 }
 228 EXPORT_SYMBOL_GPL(power_supply_register);
 229
 230 void power_supply_unregister(struct power_supply *psy)
 231 {
 232         cancel_work_sync(&psy->changed_work);
 233         power_supply_remove_triggers(psy);
 234         wake_lock_destroy(&psy->work_wake_lock);
 235         device_unregister(psy->dev);
 236 }
 237 EXPORT_SYMBOL_GPL(power_supply_unregister);
 238
 239 static int __init power_supply_class_init(void)
 240 {
 241         power_supply_class = class_create(THIS_MODULE, "power_supply");
 242
 243         if (IS_ERR(power_supply_class))
 244                 return PTR_ERR(power_supply_class);
 245
 246         power_supply_class->dev_uevent = power_supply_uevent;
 247         power_supply_init_attrs(&power_supply_dev_type);
 248
 249         return 0;
 250 }
 251
 252 static void __exit power_supply_class_exit(void)
 253 {
 254         class_destroy(power_supply_class);
 255 }
 256
 257 subsys_initcall(power_supply_class_init);
 258 module_exit(power_supply_class_exit);
 259
 260 MODULE_DESCRIPTION("Universal power supply monitor class");
 261 MODULE_AUTHOR("Ian Molton <spyro@f2s.com>, "
 262               "Szabolcs Gyurko, "
 263               "Anton Vorontsov <cbou@mail.ru>");
 264 MODULE_LICENSE("GPL");