summaryrefslogtreecommitdiff
path: root/drivers/power/jz4740-battery.c
diff options
context:
space:
mode:
authorLars-Peter Clausen <lars@metafoo.de>2010-11-11 21:00:52 +0300
committerAnton Vorontsov <cbouatmailru@gmail.com>2010-11-18 16:56:16 +0300
commit8ec98fe0b4ffdedce4c1caa9fb3d550f52ad1c6b (patch)
treeaf77279c42d3c1e9e21676b1d28ca8ec1c043c73 /drivers/power/jz4740-battery.c
parent86af95039b69a90db15294eb1f9c147f1df0a8ea (diff)
downloadlinux-8ec98fe0b4ffdedce4c1caa9fb3d550f52ad1c6b.tar.xz
jz4740-battery: Protect against concurrent battery readings
We can not handle more then one ADC request at a time to the battery. The patch adds a mutex around the ADC read code to ensure this. Signed-off-by: Lars-Peter Clausen <lars@metafoo.de> Cc: stable@kernel.org Signed-off-by: Anton Vorontsov <cbouatmailru@gmail.com>
Diffstat (limited to 'drivers/power/jz4740-battery.c')
-rw-r--r--drivers/power/jz4740-battery.c7
1 files changed, 7 insertions, 0 deletions
diff --git a/drivers/power/jz4740-battery.c b/drivers/power/jz4740-battery.c
index a8108a73593e..2bbe04ae13a7 100644
--- a/drivers/power/jz4740-battery.c
+++ b/drivers/power/jz4740-battery.c
@@ -47,6 +47,8 @@ struct jz_battery {
struct power_supply battery;
struct delayed_work work;
+
+ struct mutex lock;
};
static inline struct jz_battery *psy_to_jz_battery(struct power_supply *psy)
@@ -68,6 +70,8 @@ static long jz_battery_read_voltage(struct jz_battery *battery)
unsigned long val;
long voltage;
+ mutex_lock(&battery->lock);
+
INIT_COMPLETION(battery->read_completion);
enable_irq(battery->irq);
@@ -91,6 +95,8 @@ static long jz_battery_read_voltage(struct jz_battery *battery)
battery->cell->disable(battery->pdev);
disable_irq(battery->irq);
+ mutex_unlock(&battery->lock);
+
return voltage;
}
@@ -291,6 +297,7 @@ static int __devinit jz_battery_probe(struct platform_device *pdev)
jz_battery->pdev = pdev;
init_completion(&jz_battery->read_completion);
+ mutex_init(&jz_battery->lock);
INIT_DELAYED_WORK(&jz_battery->work, jz_battery_work);