regulator: lock supply in regulator enable

This patch add locks around regulator supply enable.

Signed-off-by: Mattias Wallin <mattias.wallin@stericsson.com>
Acked-by: Mark Brown <broonie@opensource.wolfsonmicro.com>
Signed-off-by: Liam Girdwood <lrg@slimlogic.co.uk>

1 files changed, 2 insertions, 0 deletions

diff --git a/drivers/regulator/core.c b/drivers/regulator/core.c
index 711fa1722bce..27d062e1395c 100644
--- a/drivers/regulator/core.c
+++ b/drivers/regulator/core.c
@@ -1269,7 +1269,9 @@ static int _regulator_enable(struct regulator_dev *rdev)
 
         /* 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);