4.4-stable review patch. If anyone has any objections, please let me know. ------------------ From: Thierry Reding <treding@xxxxxxxxxx> commit 70a7fb80e85ae7f78f8e90cec3fbd862ea6a4d4b upstream. Commit fa731ac7ea04 ("regulator: core: avoid unused variable warning") introduced a subtle change in how supplies are locked. Where previously code was always locking the regulator of the current iteration, the new implementation only locks the regulator if it has a supply. For any given power tree that means that the root will never get locked. On the other hand the regulator_unlock_supply() will still release all the locks, which in turn causes the lock debugging code to warn about a mutex being unlocked which wasn't locked. Cc: Mark Brown <broonie@xxxxxxxxxx> Cc: Arnd Bergmann <arnd@xxxxxxxx> Fixes: Fixes: fa731ac7ea04 ("regulator: core: avoid unused variable warning") Signed-off-by: Thierry Reding <treding@xxxxxxxxxx> Signed-off-by: Mark Brown <broonie@xxxxxxxxxx> Signed-off-by: Greg Kroah-Hartman <gregkh@xxxxxxxxxxxxxxxxxxx> --- drivers/regulator/core.c | 10 +++++++++- 1 file changed, 9 insertions(+), 1 deletion(-) --- a/drivers/regulator/core.c +++ b/drivers/regulator/core.c @@ -132,6 +132,14 @@ static bool have_full_constraints(void) return has_full_constraints || of_have_populated_dt(); } +static inline struct regulator_dev *rdev_get_supply(struct regulator_dev *rdev) +{ + if (rdev && rdev->supply) + return rdev->supply->rdev; + + return NULL; +} + /** * regulator_lock_supply - lock a regulator and its supplies * @rdev: regulator source @@ -140,7 +148,7 @@ static void regulator_lock_supply(struct { int i; - for (i = 0; rdev->supply; rdev = rdev->supply->rdev, i++) + for (i = 0; rdev->supply; rdev = rdev_get_supply(rdev), i++) mutex_lock_nested(&rdev->mutex, i); } -- To unsubscribe from this list: send the line "unsubscribe stable" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html