The patch below does not apply to the 4.12-stable tree. If someone wants it applied there, or to any other stable or longterm tree, then please email the backport, including the original git commit id to <stable@xxxxxxxxxxxxxxx>. thanks, greg k-h ------------------ original commit in Linus's tree ------------------ >From a359bb2a55f384bb93349ddf9d30b20b37e02e8a Mon Sep 17 00:00:00 2001 From: Fabrice Gasnier <fabrice.gasnier@xxxxxx> Date: Thu, 3 Aug 2017 11:22:17 +0200 Subject: [PATCH] iio: trigger: stm32-timer: fix get trigger mode Fix reading trigger mode, when other bit-fields are set. SMCR register value must be masked to read SMS (slave mode selection) only. Fixes: 9eba381 ("iio: make stm32 trigger driver use INDIO_HARDWARE_TRIGGERED mode") Signed-off-by: Fabrice Gasnier <fabrice.gasnier@xxxxxx> Cc: <Stable@xxxxxxxxxxxxxxx> Signed-off-by: Jonathan Cameron <Jonathan.Cameron@xxxxxxxxxx> diff --git a/drivers/iio/trigger/stm32-timer-trigger.c b/drivers/iio/trigger/stm32-timer-trigger.c index 14e6eb04bbb0..25ad6abfee22 100644 --- a/drivers/iio/trigger/stm32-timer-trigger.c +++ b/drivers/iio/trigger/stm32-timer-trigger.c @@ -485,7 +485,7 @@ static int stm32_get_trigger_mode(struct iio_dev *indio_dev, regmap_read(priv->regmap, TIM_SMCR, &smcr); - return smcr == TIM_SMCR_SMS ? 0 : -EINVAL; + return (smcr & TIM_SMCR_SMS) == TIM_SMCR_SMS ? 0 : -EINVAL; } static const struct iio_enum stm32_trigger_mode_enum = {