| From 1a9e7a04e89e151e0af0c2602c4090fb38cd14de Mon Sep 17 00:00:00 2001 |
| From: Steve Twiss <stwiss.opensource@diasemi.com> |
| Date: Tue, 26 Feb 2019 15:54:01 +0000 |
| Subject: regulator: wm831x ldo: Fix notifier mutex lock warning |
| |
| [ Upstream commit 8be64b6d87bd47d81753b60ddafe70102ebfd76b ] |
| |
| 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: d1c6b4fe668b ("regulator: Add WM831x LDO support") |
| Suggested-by: Adam Thomson <Adam.Thomson.Opensource@diasemi.com> |
| Signed-off-by: Steve Twiss <stwiss.opensource@diasemi.com> |
| Acked-by: Charles Keepax <ckeepax@opensource.cirrus.com> |
| Signed-off-by: Mark Brown <broonie@kernel.org> |
| Signed-off-by: Sasha Levin <sashal@kernel.org> |
| --- |
| drivers/regulator/wm831x-ldo.c | 2 ++ |
| 1 file changed, 2 insertions(+) |
| |
| diff --git a/drivers/regulator/wm831x-ldo.c b/drivers/regulator/wm831x-ldo.c |
| index e4a6f888484ec..fcd038e7cd803 100644 |
| --- a/drivers/regulator/wm831x-ldo.c |
| +++ b/drivers/regulator/wm831x-ldo.c |
| @@ -51,9 +51,11 @@ static irqreturn_t wm831x_ldo_uv_irq(int irq, void *data) |
| { |
| struct wm831x_ldo *ldo = data; |
| |
| + regulator_lock(ldo->regulator); |
| regulator_notifier_call_chain(ldo->regulator, |
| REGULATOR_EVENT_UNDER_VOLTAGE, |
| NULL); |
| + regulator_unlock(ldo->regulator); |
| |
| return IRQ_HANDLED; |
| } |
| -- |
| 2.20.1 |
| |
