aboutsummaryrefslogtreecommitdiff
diff options
context:
space:
mode:
authorMatthew Garrett <mjg59@srcf.ucam.org>2008-08-26 21:09:59 +0100
committerAnton Vorontsov <cbouatmailru@gmail.com>2008-09-01 02:42:54 +0400
commit942ed161944b3476639916cf544e6975b29c985a (patch)
treea05e3bd0d6b59de318f3bfc5557502c13dde1bc4
parente82374fd1a804e197fc2a54c3930e70c5d300abc (diff)
power_supply: Add function to return system-wide power state
Certain drivers benefit from knowing whether the system is on ac or battery, for instance when determining which backlight registers to read. This adds a simple call to determine whether there's an online power supply other than any batteries. Signed-off-by: Matthew Garrett <mjg@redhat.com> Signed-off-by: Anton Vorontsov <cbouatmailru@gmail.com>
-rw-r--r--drivers/power/power_supply_core.c25
-rw-r--r--include/linux/power_supply.h6
2 files changed, 31 insertions, 0 deletions
diff --git a/drivers/power/power_supply_core.c b/drivers/power/power_supply_core.c
index cb1ccb47292..f44f5b608f6 100644
--- a/drivers/power/power_supply_core.c
+++ b/drivers/power/power_supply_core.c
@@ -87,6 +87,30 @@ int power_supply_am_i_supplied(struct power_supply *psy)
return error;
}
+static int __power_supply_is_system_supplied(struct device *dev, void *data)
+{
+ union power_supply_propval ret = {0,};
+ struct power_supply *psy = dev_get_drvdata(dev);
+
+ if (psy->type != POWER_SUPPLY_TYPE_BATTERY) {
+ if (psy->get_property(psy, POWER_SUPPLY_PROP_ONLINE, &ret))
+ return 0;
+ if (ret.intval)
+ return ret.intval;
+ }
+ return 0;
+}
+
+int power_supply_is_system_supplied(void)
+{
+ int error;
+
+ error = class_for_each_device(power_supply_class, NULL, NULL,
+ __power_supply_is_system_supplied);
+
+ return error;
+}
+
int power_supply_register(struct device *parent, struct power_supply *psy)
{
int rc = 0;
@@ -148,6 +172,7 @@ static void __exit power_supply_class_exit(void)
EXPORT_SYMBOL_GPL(power_supply_changed);
EXPORT_SYMBOL_GPL(power_supply_am_i_supplied);
+EXPORT_SYMBOL_GPL(power_supply_is_system_supplied);
EXPORT_SYMBOL_GPL(power_supply_register);
EXPORT_SYMBOL_GPL(power_supply_unregister);
diff --git a/include/linux/power_supply.h b/include/linux/power_supply.h
index ea96ead1d39..f9348cba6dc 100644
--- a/include/linux/power_supply.h
+++ b/include/linux/power_supply.h
@@ -165,6 +165,12 @@ struct power_supply_info {
extern void power_supply_changed(struct power_supply *psy);
extern int power_supply_am_i_supplied(struct power_supply *psy);
+#if defined(CONFIG_POWER_SUPPLY) || defined(CONFIG_POWER_SUPPLY_MODULE)
+extern int power_supply_is_system_supplied(void);
+#else
+static inline int power_supply_is_system_supplied(void) { return -ENOSYS; }
+#endif
+
extern int power_supply_register(struct device *parent,
struct power_supply *psy);
extern void power_supply_unregister(struct power_supply *psy);