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 <linux/thermal.h>
  21 #include "power_supply.h"
  22
  23 /* exported for the APM Power driver, APM emulation */
  24 struct class *power_supply_class;
  25 EXPORT_SYMBOL_GPL(power_supply_class);
  26
  27 static struct device_type power_supply_dev_type;
  28
  29 static int __power_supply_changed_work(struct device *dev, void *data)
  30 {
  31         struct power_supply *psy = (struct power_supply *)data;
  32         struct power_supply *pst = dev_get_drvdata(dev);
  33         int i;
  34
  35         for (i = 0; i < psy->num_supplicants; i++)
  36                 if (!strcmp(psy->supplied_to[i], pst->name)) {
  37                         if (pst->external_power_changed)
  38                                 pst->external_power_changed(pst);
  39                 }
  40         return 0;
  41 }
  42
  43 static void power_supply_changed_work(struct work_struct *work)
  44 {
  45         struct power_supply *psy = container_of(work, struct power_supply,
  46                                                 changed_work);
  47
  48         dev_dbg(psy->dev, "%s\n", __func__);
  49
  50         class_for_each_device(power_supply_class, NULL, psy,
  51                               __power_supply_changed_work);
  52
  53         power_supply_update_leds(psy);
  54
  55         kobject_uevent(&psy->dev->kobj, KOBJ_CHANGE);
  56 }
  57
  58 void power_supply_changed(struct power_supply *psy)
  59 {
  60         dev_dbg(psy->dev, "%s\n", __func__);
  61
  62         schedule_work(&psy->changed_work);
  63 }
  64 EXPORT_SYMBOL_GPL(power_supply_changed);
  65
  66 static int __power_supply_am_i_supplied(struct device *dev, void *data)
  67 {
  68         union power_supply_propval ret = {0,};
  69         struct power_supply *psy = (struct power_supply *)data;
  70         struct power_supply *epsy = dev_get_drvdata(dev);
  71         int i;
  72
  73         for (i = 0; i < epsy->num_supplicants; i++) {
  74                 if (!strcmp(epsy->supplied_to[i], psy->name)) {
  75                         if (epsy->get_property(epsy,
  76                                   POWER_SUPPLY_PROP_ONLINE, &ret))
  77                                 continue;
  78                         if (ret.intval)
  79                                 return ret.intval;
  80                 }
  81         }
  82         return 0;
  83 }
  84
  85 int power_supply_am_i_supplied(struct power_supply *psy)
  86 {
  87         int error;
  88
  89         error = class_for_each_device(power_supply_class, NULL, psy,
  90                                       __power_supply_am_i_supplied);
  91
  92         dev_dbg(psy->dev, "%s %d\n", __func__, error);
  93
  94         return error;
  95 }
  96 EXPORT_SYMBOL_GPL(power_supply_am_i_supplied);
  97
  98 static int __power_supply_is_system_supplied(struct device *dev, void *data)
  99 {
 100         union power_supply_propval ret = {0,};
 101         struct power_supply *psy = dev_get_drvdata(dev);
 102         unsigned int *count = data;
 103
 104         (*count)++;
 105         if (psy->type != POWER_SUPPLY_TYPE_BATTERY) {
 106                 if (psy->get_property(psy, POWER_SUPPLY_PROP_ONLINE, &ret))
 107                         return 0;
 108                 if (ret.intval)
 109                         return ret.intval;
 110         }
 111         return 0;
 112 }
 113
 114 int power_supply_is_system_supplied(void)
 115 {
 116         int error;
 117         unsigned int count = 0;
 118
 119         error = class_for_each_device(power_supply_class, NULL, &count,
 120                                       __power_supply_is_system_supplied);
 121
 122         /*
 123          * If no power class device was found at all, most probably we are
 124          * running on a desktop system, so assume we are on mains power.
 125          */
 126         if (count == 0)
 127                 return 1;
 128
 129         return error;
 130 }
 131 EXPORT_SYMBOL_GPL(power_supply_is_system_supplied);
 132
 133 int power_supply_set_battery_charged(struct power_supply *psy)
 134 {
 135         if (psy->type == POWER_SUPPLY_TYPE_BATTERY && psy->set_charged) {
 136                 psy->set_charged(psy);
 137                 return 0;
 138         }
 139
 140         return -EINVAL;
 141 }
 142 EXPORT_SYMBOL_GPL(power_supply_set_battery_charged);
 143
 144 static int power_supply_match_device_by_name(struct device *dev, void *data)
 145 {
 146         const char *name = data;
 147         struct power_supply *psy = dev_get_drvdata(dev);
 148
 149         return strcmp(psy->name, name) == 0;
 150 }
 151
 152 struct power_supply *power_supply_get_by_name(char *name)
 153 {
 154         struct device *dev = class_find_device(power_supply_class, NULL, name,
 155                                         power_supply_match_device_by_name);
 156
 157         return dev ? dev_get_drvdata(dev) : NULL;
 158 }
 159 EXPORT_SYMBOL_GPL(power_supply_get_by_name);
 160
 161 int power_supply_powers(struct power_supply *psy, struct device *dev)
 162 {
 163         return sysfs_create_link(&psy->dev->kobj, &dev->kobj, "powers");
 164 }
 165 EXPORT_SYMBOL_GPL(power_supply_powers);
 166
 167 static void power_supply_dev_release(struct device *dev)
 168 {
 169         pr_debug("device: '%s': %s\n", dev_name(dev), __func__);
 170         kfree(dev);
 171 }
 172
 173 #ifdef CONFIG_THERMAL
 174 static int power_supply_read_temp(struct thermal_zone_device *tzd,
 175                 unsigned long *temp)
 176 {
 177         struct power_supply *psy;
 178         union power_supply_propval val;
 179         int ret;
 180
 181         WARN_ON(tzd == NULL);
 182         psy = tzd->devdata;
 183         ret = psy->get_property(psy, POWER_SUPPLY_PROP_TEMP, &val);
 184
 185         /* Convert tenths of degree Celsius to milli degree Celsius. */
 186         if (!ret)
 187                 *temp = val.intval * 100;
 188
 189         return ret;
 190 }
 191
 192 static struct thermal_zone_device_ops psy_tzd_ops = {
 193         .get_temp = power_supply_read_temp,
 194 };
 195
 196 static int psy_register_thermal(struct power_supply *psy)
 197 {
 198         int i;
 199
 200         /* Register battery zone device psy reports temperature */
 201         for (i = 0; i < psy->num_properties; i++) {
 202                 if (psy->properties[i] == POWER_SUPPLY_PROP_TEMP) {
 203                         psy->tzd = thermal_zone_device_register(psy->name, 0, 0,
 204                                         psy, &psy_tzd_ops, NULL, 0, 0);
 205                         if (IS_ERR(psy->tzd))
 206                                 return PTR_ERR(psy->tzd);
 207                         break;
 208                 }
 209         }
 210         return 0;
 211 }
 212
 213 static void psy_unregister_thermal(struct power_supply *psy)
 214 {
 215         if (IS_ERR_OR_NULL(psy->tzd))
 216                 return;
 217         thermal_zone_device_unregister(psy->tzd);
 218 }
 219
 220 /* thermal cooling device callbacks */
 221 static int ps_get_max_charge_cntl_limit(struct thermal_cooling_device *tcd,
 222                                         unsigned long *state)
 223 {
 224         struct power_supply *psy;
 225         union power_supply_propval val;
 226         int ret;
 227
 228         psy = tcd->devdata;
 229         ret = psy->get_property(psy,
 230                 POWER_SUPPLY_PROP_CHARGE_CONTROL_LIMIT_MAX, &val);
 231         if (!ret)
 232                 *state = val.intval;
 233
 234         return ret;
 235 }
 236
 237 static int ps_get_cur_chrage_cntl_limit(struct thermal_cooling_device *tcd,
 238                                         unsigned long *state)
 239 {
 240         struct power_supply *psy;
 241         union power_supply_propval val;
 242         int ret;
 243
 244         psy = tcd->devdata;
 245         ret = psy->get_property(psy,
 246                 POWER_SUPPLY_PROP_CHARGE_CONTROL_LIMIT, &val);
 247         if (!ret)
 248                 *state = val.intval;
 249
 250         return ret;
 251 }
 252
 253 static int ps_set_cur_charge_cntl_limit(struct thermal_cooling_device *tcd,
 254                                         unsigned long state)
 255 {
 256         struct power_supply *psy;
 257         union power_supply_propval val;
 258         int ret;
 259
 260         psy = tcd->devdata;
 261         val.intval = state;
 262         ret = psy->set_property(psy,
 263                 POWER_SUPPLY_PROP_CHARGE_CONTROL_LIMIT, &val);
 264
 265         return ret;
 266 }
 267
 268 static struct thermal_cooling_device_ops psy_tcd_ops = {
 269         .get_max_state = ps_get_max_charge_cntl_limit,
 270         .get_cur_state = ps_get_cur_chrage_cntl_limit,
 271         .set_cur_state = ps_set_cur_charge_cntl_limit,
 272 };
 273
 274 static int psy_register_cooler(struct power_supply *psy)
 275 {
 276         int i;
 277
 278         /* Register for cooling device if psy can control charging */
 279         for (i = 0; i < psy->num_properties; i++) {
 280                 if (psy->properties[i] ==
 281                                 POWER_SUPPLY_PROP_CHARGE_CONTROL_LIMIT) {
 282                         psy->tcd = thermal_cooling_device_register(
 283                                                         (char *)psy->name,
 284                                                         psy, &psy_tcd_ops);
 285                         if (IS_ERR(psy->tcd))
 286                                 return PTR_ERR(psy->tcd);
 287                         break;
 288                 }
 289         }
 290         return 0;
 291 }
 292
 293 static void psy_unregister_cooler(struct power_supply *psy)
 294 {
 295         if (IS_ERR_OR_NULL(psy->tcd))
 296                 return;
 297         thermal_cooling_device_unregister(psy->tcd);
 298 }
 299 #else
 300 static int psy_register_thermal(struct power_supply *psy)
 301 {
 302         return 0;
 303 }
 304
 305 static void psy_unregister_thermal(struct power_supply *psy)
 306 {
 307 }
 308
 309 static int psy_register_cooler(struct power_supply *psy)
 310 {
 311         return 0;
 312 }
 313
 314 static void psy_unregister_cooler(struct power_supply *psy)
 315 {
 316 }
 317 #endif
 318
 319 int power_supply_register(struct device *parent, struct power_supply *psy)
 320 {
 321         struct device *dev;
 322         int rc;
 323
 324         dev = kzalloc(sizeof(*dev), GFP_KERNEL);
 325         if (!dev)
 326                 return -ENOMEM;
 327
 328         device_initialize(dev);
 329
 330         dev->class = power_supply_class;
 331         dev->type = &power_supply_dev_type;
 332         dev->parent = parent;
 333         dev->release = power_supply_dev_release;
 334         dev_set_drvdata(dev, psy);
 335         psy->dev = dev;
 336
 337         INIT_WORK(&psy->changed_work, power_supply_changed_work);
 338
 339         rc = kobject_set_name(&dev->kobj, "%s", psy->name);
 340         if (rc)
 341                 goto kobject_set_name_failed;
 342
 343         rc = device_add(dev);
 344         if (rc)
 345                 goto device_add_failed;
 346
 347         rc = psy_register_thermal(psy);
 348         if (rc)
 349                 goto register_thermal_failed;
 350
 351         rc = psy_register_cooler(psy);
 352         if (rc)
 353                 goto register_cooler_failed;
 354
 355         rc = power_supply_create_triggers(psy);
 356         if (rc)
 357                 goto create_triggers_failed;
 358
 359         power_supply_changed(psy);
 360
 361         goto success;
 362
 363 create_triggers_failed:
 364         psy_unregister_cooler(psy);
 365 register_cooler_failed:
 366         psy_unregister_thermal(psy);
 367 register_thermal_failed:
 368         device_del(dev);
 369 kobject_set_name_failed:
 370 device_add_failed:
 371         put_device(dev);
 372 success:
 373         return rc;
 374 }
 375 EXPORT_SYMBOL_GPL(power_supply_register);
 376
 377 void power_supply_unregister(struct power_supply *psy)
 378 {
 379         cancel_work_sync(&psy->changed_work);
 380         sysfs_remove_link(&psy->dev->kobj, "powers");
 381         power_supply_remove_triggers(psy);
 382         psy_unregister_cooler(psy);
 383         psy_unregister_thermal(psy);
 384         device_unregister(psy->dev);
 385 }
 386 EXPORT_SYMBOL_GPL(power_supply_unregister);
 387
 388 static int __init power_supply_class_init(void)
 389 {
 390         power_supply_class = class_create(THIS_MODULE, "power_supply");
 391
 392         if (IS_ERR(power_supply_class))
 393                 return PTR_ERR(power_supply_class);
 394
 395         power_supply_class->dev_uevent = power_supply_uevent;
 396         power_supply_init_attrs(&power_supply_dev_type);
 397
 398         return 0;
 399 }
 400
 401 static void __exit power_supply_class_exit(void)
 402 {
 403         class_destroy(power_supply_class);
 404 }
 405
 406 subsys_initcall(power_supply_class_init);
 407 module_exit(power_supply_class_exit);
 408
 409 MODULE_DESCRIPTION("Universal power supply monitor class");
 410 MODULE_AUTHOR("Ian Molton <spyro@f2s.com>, "
 411               "Szabolcs Gyurko, "
 412               "Anton Vorontsov <cbou@mail.ru>");
 413 MODULE_LICENSE("GPL");