This is a note to let you know that I've just added the patch titled
pwm: stm32-lp: fix the check on arr and cmp registers update
to the 4.14-stable tree which can be found at:
http://www.kernel.org/git/?p=linux/kernel/git/stable/stable-queue.git;a=summary
The filename of the patch is:
pwm-stm32-lp-fix-the-check-on-arr-and-cmp-registers-.patch
and it can be found in the queue-4.14 subdirectory.
If you, or anyone else, feels it should not be added to the stable tree,
please let <stable@xxxxxxxxxxxxxxx> know about it.
commit 9494172fdd3e39053aa96c069c0d67845ba6628e
Author: Fabrice Gasnier <fabrice.gasnier@xxxxxxxxxxx>
Date: Wed Nov 23 14:36:52 2022 +0100
pwm: stm32-lp: fix the check on arr and cmp registers update
[ Upstream commit 3066bc2d58be31275afb51a589668f265e419c37 ]
The ARR (auto reload register) and CMP (compare) registers are
successively written. The status bits to check the update of these
registers are polled together with regmap_read_poll_timeout().
The condition to end the loop may become true, even if one of the
register isn't correctly updated.
So ensure both status bits are set before clearing them.
Fixes: e70a540b4e02 ("pwm: Add STM32 LPTimer PWM driver")
Signed-off-by: Fabrice Gasnier <fabrice.gasnier@xxxxxxxxxxx>
Acked-by: Uwe Kleine-König <u.kleine-koenig@xxxxxxxxxxxxxx>
Signed-off-by: Thierry Reding <thierry.reding@xxxxxxxxx>
Signed-off-by: Sasha Levin <sashal@xxxxxxxxxx>
diff --git a/drivers/pwm/pwm-stm32-lp.c b/drivers/pwm/pwm-stm32-lp.c
index 3f2e4ef695d75..ba0aa3b8076b1 100644
--- a/drivers/pwm/pwm-stm32-lp.c
+++ b/drivers/pwm/pwm-stm32-lp.c
@@ -127,7 +127,7 @@ static int stm32_pwm_lp_apply(struct pwm_chip *chip, struct pwm_device *pwm,
/* ensure CMP & ARR registers are properly written */
ret = regmap_read_poll_timeout(priv->regmap, STM32_LPTIM_ISR, val,
- (val & STM32_LPTIM_CMPOK_ARROK),
+ (val & STM32_LPTIM_CMPOK_ARROK) == STM32_LPTIM_CMPOK_ARROK,
100, 1000);
if (ret) {
dev_err(priv->chip.dev, "ARR/CMP registers write issue\n");
