Dummy write in capture master mode is used to gate bus clocks. This write is useless in slave mode as the clocks are not managed by slave.
Signed-off-by: Olivier Moysan olivier.moysan@st.com --- sound/soc/stm/stm32_i2s.c | 4 ++-- 1 file changed, 2 insertions(+), 2 deletions(-)
diff --git a/sound/soc/stm/stm32_i2s.c b/sound/soc/stm/stm32_i2s.c index 42ce87a35104..47c334de6b09 100644 --- a/sound/soc/stm/stm32_i2s.c +++ b/sound/soc/stm/stm32_i2s.c @@ -623,8 +623,8 @@ static int stm32_i2s_trigger(struct snd_pcm_substream *substream, int cmd, } else { ier = I2S_IER_OVRIE;
- if (i2s->refcount == 1) - /* dummy write to trigger capture */ + if (STM32_I2S_IS_MASTER(i2s) && i2s->refcount == 1) + /* dummy write to gate bus clocks */ regmap_write(i2s->regmap, STM32_I2S_TXDR_REG, 0); }