regulator: lock supply in regulator enable

This patch add locks around regulator supply enable.
Signed-off-by: NMattias Wallin <mattias.wallin@stericsson.com>
Acked-by: NMark Brown <broonie@opensource.wolfsonmicro.com>
Signed-off-by: NLiam Girdwood <lrg@slimlogic.co.uk>

drivers/regulator/core.c

@@ -1267,17 +1267,15 @@ static int _regulator_enable(struct regulator_dev *rdev)
 {
 	int ret, delay;
 
-	if (rdev->use_count == 0) {
-		/* do we need to enable the supply regulator first */
-		if (rdev->supply) {
-			mutex_lock(&rdev->supply->mutex);
-			ret = _regulator_enable(rdev->supply);
-			mutex_unlock(&rdev->supply->mutex);
-			if (ret < 0) {
-				printk(KERN_ERR "%s: failed to enable %s: %d\n",
-				       __func__, rdev_get_name(rdev), ret);
-				return ret;
-			}
+	/* do we need to enable the supply regulator first */
+	if (rdev->supply) {
+		mutex_lock(&rdev->supply->mutex);
+		ret = _regulator_enable(rdev->supply);
+		mutex_unlock(&rdev->supply->mutex);
+		if (ret < 0) {
+			printk(KERN_ERR "%s: failed to enable %s: %d\n",
+			       __func__, rdev_get_name(rdev), ret);
+			return ret;
 		}
 	}