diff --git a/drivers/acpi/battery.c b/drivers/acpi/battery.c
index f9ba601f671e..f7e7041c39c9 100644
--- a/drivers/acpi/battery.c
+++ b/drivers/acpi/battery.c
@@ -689,9 +689,13 @@ static ssize_t acpi_battery_alarm_store(struct device *dev,
 {
 	unsigned long x;
 	struct acpi_battery *battery = to_acpi_battery(dev_get_drvdata(dev));
+	int err;
 
-	if (sscanf(buf, "%lu\n", &x) == 1)
-		battery->alarm = x/1000;
+	err = kstrtoul(buf, 10, &x);
+	if (err)
+		return err;
+
+	battery->alarm = x / 1000;
 	if (acpi_battery_present(battery))
 		acpi_battery_set_alarm(battery);
 	return count;