[PATCH 1/2] regulator: core: Add a sanity check on the regulator_ enable/disable functions

[Gregory CLEMENT <gregory.clement@free-electrons.com>]

These two functions use the pointer passed in parameter without any
check. By adding a NULL pointer check, it allows using those functions
from a driver in a more generic way. It is useful especially for the
disable case if the regulator is optional.

Signed-off-by: Gregory CLEMENT <gregory.clement@free-electrons.com>
---
 drivers/regulator/core.c | 13 +++++++++++--
 1 file changed, 11 insertions(+), 2 deletions(-)

diff --git a/drivers/regulator/core.c b/drivers/regulator/core.c
index e225711bb8bc..de29399b5430 100644
--- a/drivers/regulator/core.c
+++ b/drivers/regulator/core.c
@@ -1911,12 +1911,16 @@ static int _regulator_enable(struct regulator_dev *rdev)
  */
 int regulator_enable(struct regulator *regulator)
 {
-	struct regulator_dev *rdev = regulator->rdev;
+	struct regulator_dev *rdev;
 	int ret = 0;
 
+	if (!regulator)
+		return 0;
+
 	if (regulator->always_on)
 		return 0;
 
+	rdev = regulator->rdev;
 	if (rdev->supply) {
 		ret = regulator_enable(rdev->supply);
 		if (ret != 0)
@@ -2024,12 +2028,17 @@ static int _regulator_disable(struct regulator_dev *rdev)
  */
 int regulator_disable(struct regulator *regulator)
 {
-	struct regulator_dev *rdev = regulator->rdev;
+	struct regulator_dev *rdev;
 	int ret = 0;
 
+	if (!regulator)
+		return 0;
+
 	if (regulator->always_on)
 		return 0;
 
+	rdev = regulator->rdev;
+
 	mutex_lock(&rdev->mutex);
 	ret = _regulator_disable(rdev);
 	mutex_unlock(&rdev->mutex);
-- 
1.9.1