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authorMatthew Garrett <mjg59@srcf.ucam.org>2008-08-26 22:09:59 +0200
committerAnton Vorontsov <cbouatmailru@gmail.com>2008-09-01 00:42:54 +0200
commit942ed161944b3476639916cf544e6975b29c985a (patch)
treea05e3bd0d6b59de318f3bfc5557502c13dde1bc4 /drivers/power
parentpda_power: Check and handle return value of set_irq_wake (diff)
downloadlinux-942ed161944b3476639916cf544e6975b29c985a.tar.xz
linux-942ed161944b3476639916cf544e6975b29c985a.zip
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>
Diffstat (limited to 'drivers/power')
-rw-r--r--drivers/power/power_supply_core.c25
1 files changed, 25 insertions, 0 deletions
diff --git a/drivers/power/power_supply_core.c b/drivers/power/power_supply_core.c
index cb1ccb472921..f44f5b608f6a 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);