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authorJean Delvare <jdelvare@suse.de>2011-12-10 21:53:36 (GMT)
committerAnton Vorontsov <cbouatmailru@gmail.com>2012-01-06 01:50:32 (GMT)
commit2530daa187be3adef2d7cb41bd51f1384e478f2b (patch)
treef4210ee87310b4e8e2dbbd45ebb98f25d80c0249 /drivers/power
parent62df3935a7ef842ad0af6025d2fc59d353de2e1d (diff)
downloadlinux-2530daa187be3adef2d7cb41bd51f1384e478f2b.tar.xz
power_supply: Assume mains power by default
If no power class device is found in power_supply_is_system_supplied(), the function currently returns 0, which basically means that the system is supposed to be running on battery. In practice, mobile devices tend to always implement at least one power class device and more often two (battery and AC adapter). Systems with no registered power class devices are more likely to be desktop systems, where the system is always powered by mains. So, change the default return value of power_supply_is_system_supplied() from 0 (running on battery) to 1 (running on mains.) Signed-off-by: Jean Delvare <jdelvare@suse.de> Cc: David Woodhouse <dwmw2@infradead.org> Cc: Matthew Garrett <mjg59@srcf.ucam.org> Cc: Alex Deucher <alexander.deucher@amd.com> Signed-off-by: Anton Vorontsov <cbouatmailru@gmail.com>
Diffstat (limited to 'drivers/power')
-rw-r--r--drivers/power/power_supply_core.c12
1 files changed, 11 insertions, 1 deletions
diff --git a/drivers/power/power_supply_core.c b/drivers/power/power_supply_core.c
index b10c121..bc82f95 100644
--- a/drivers/power/power_supply_core.c
+++ b/drivers/power/power_supply_core.c
@@ -98,7 +98,9 @@ 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);
+ unsigned int *count = data;
+ (*count)++;
if (psy->type != POWER_SUPPLY_TYPE_BATTERY) {
if (psy->get_property(psy, POWER_SUPPLY_PROP_ONLINE, &ret))
return 0;
@@ -111,10 +113,18 @@ static int __power_supply_is_system_supplied(struct device *dev, void *data)
int power_supply_is_system_supplied(void)
{
int error;
+ unsigned int count = 0;
- error = class_for_each_device(power_supply_class, NULL, NULL,
+ error = class_for_each_device(power_supply_class, NULL, &count,
__power_supply_is_system_supplied);
+ /*
+ * If no power class device was found at all, most probably we are
+ * running on a desktop system, so assume we are on mains power.
+ */
+ if (count == 0)
+ return 1;
+
return error;
}
EXPORT_SYMBOL_GPL(power_supply_is_system_supplied);