[PATCH 02/13] regulator: da9062: Fix notifier mutex lock warning

From: Steve Twiss
Date: Tue Mar 05 2019 - 13:09:34 EST

The mutex for the regulator_dev must be controlled by the caller of
the regulator_notifier_call_chain(), as described in the comment
for that function.

Failure to mutex lock and unlock surrounding the notifier call results
in a kernel WARN_ON_ONCE() which will dump a backtrace for the
regulator_notifier_call_chain() when that function call is first made.
The mutex can be controlled using the regulator_lock/unlock() API.

Fixes: 4068e5182ada ("regulator: da9062: DA9062 regulator driver")
Suggested-by: Adam Thomson <Adam.Thomson.Opensource@xxxxxxxxxxx>
Signed-off-by: Steve Twiss <stwiss.opensource@xxxxxxxxxxx>
drivers/regulator/da9062-regulator.c | 2 ++
1 file changed, 2 insertions(+)

diff --git a/drivers/regulator/da9062-regulator.c b/drivers/regulator/da9062-regulator.c
index 34a70d9..5224304 100644
--- a/drivers/regulator/da9062-regulator.c
+++ b/drivers/regulator/da9062-regulator.c
@@ -974,8 +974,10 @@ static irqreturn_t da9062_ldo_lim_event(int irq, void *data)

if (BIT(regl->info->oc_event.lsb) & bits) {
+ regulator_lock(regl->rdev);
+ regulator_unlock(regl->rdev);
handled = IRQ_HANDLED;