Messages in this thread Patch in this message | | | From | Thierry Reding <> | Subject | [PATCH] regulator: core: Fix nested locking of supplies | Date | Wed, 2 Dec 2015 16:54:50 +0100 |
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From: Thierry Reding <treding@nvidia.com>
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@kernel.org> Cc: Arnd Bergmann <arnd@arndb.de> Fixes: Fixes: fa731ac7ea04 ("regulator: core: avoid unused variable warning") Signed-off-by: Thierry Reding <treding@nvidia.com> --- drivers/regulator/core.c | 10 +++++++++- 1 file changed, 9 insertions(+), 1 deletion(-)
diff --git a/drivers/regulator/core.c b/drivers/regulator/core.c index c9bdca5f3b9b..6653b1b4ff0f 100644 --- 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 regulator_dev *rdev) { int i; - for (i = 0; rdev->supply; rdev = rdev->supply->rdev, i++) + for (i = 0; rdev; rdev = rdev_get_supply(rdev), i++) mutex_lock_nested(&rdev->mutex, i); } -- 2.5.0
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