--- 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(stru
- 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(stru
- battery->cell->disable(battery->pdev);
- disable_irq(battery->irq);
-
-+ mutex_unlock(&battery->lock);
-+
- return voltage;
- }
-
-@@ -240,6 +246,11 @@ static int __devinit jz_battery_probe(st
+@@ -246,6 +246,11 @@ static int __devinit jz_battery_probe(st
struct jz_battery *jz_battery;
struct power_supply *battery;
jz_battery = kzalloc(sizeof(*jz_battery), GFP_KERNEL);
if (!jz_battery) {
dev_err(&pdev->dev, "Failed to allocate driver structure\n");
-@@ -291,6 +302,7 @@ static int __devinit jz_battery_probe(st
- jz_battery->pdev = pdev;
-
- init_completion(&jz_battery->read_completion);
-+ mutex_init(&jz_battery->lock);
-
- INIT_DELAYED_WORK(&jz_battery->work, jz_battery_work);
-