[PATCH] iio: trigger: stm32-timer: disable master mode when stopping

From: Fabrice Gasnier
Date: Fri Feb 14 2020 - 11:48:16 EST


Master mode should be disabled when stopping. This mainly impacts
possible other use-case after timer has been stopped. Currently,
master mode remains set (from start routine).

Fixes: 6fb34812c2a2 ("iio: stm32 trigger: Add support for TRGO2 triggers")

Signed-off-by: Fabrice Gasnier <fabrice.gasnier@xxxxxx>
---
drivers/iio/trigger/stm32-timer-trigger.c | 11 +++++++++--
1 file changed, 9 insertions(+), 2 deletions(-)

diff --git a/drivers/iio/trigger/stm32-timer-trigger.c b/drivers/iio/trigger/stm32-timer-trigger.c
index 2e0d32a..2f82e8c 100644
--- a/drivers/iio/trigger/stm32-timer-trigger.c
+++ b/drivers/iio/trigger/stm32-timer-trigger.c
@@ -161,7 +161,8 @@ static int stm32_timer_start(struct stm32_timer_trigger *priv,
return 0;
}

-static void stm32_timer_stop(struct stm32_timer_trigger *priv)
+static void stm32_timer_stop(struct stm32_timer_trigger *priv,
+ struct iio_trigger *trig)
{
u32 ccer, cr1;

@@ -179,6 +180,12 @@ static void stm32_timer_stop(struct stm32_timer_trigger *priv)
regmap_write(priv->regmap, TIM_PSC, 0);
regmap_write(priv->regmap, TIM_ARR, 0);

+ /* Force disable master mode */
+ if (stm32_timer_is_trgo2_name(trig->name))
+ regmap_update_bits(priv->regmap, TIM_CR2, TIM_CR2_MMS2, 0);
+ else
+ regmap_update_bits(priv->regmap, TIM_CR2, TIM_CR2_MMS, 0);
+
/* Make sure that registers are updated */
regmap_update_bits(priv->regmap, TIM_EGR, TIM_EGR_UG, TIM_EGR_UG);
}
@@ -197,7 +204,7 @@ static ssize_t stm32_tt_store_frequency(struct device *dev,
return ret;

if (freq == 0) {
- stm32_timer_stop(priv);
+ stm32_timer_stop(priv, trig);
} else {
ret = stm32_timer_start(priv, trig, freq);
if (ret)
--
2.7.4