[alsa-devel] [PATCH 1/3] ASoC: stm32: spdifrx: update pcm hardware constraints

[Olivier Moysan]

- Set period minimum size. Ensure at least 5ms period
up to 48kHz/16 bits to prevent underrun/overrun.
- Remove MDMA constraints on period maximum size and
set period maximum to half the buffer maximum size.

Signed-off-by: Olivier Moysan <olivier.moysan at st.com>
---
 sound/soc/stm/stm32_spdifrx.c | 3 ++-
 1 file changed, 2 insertions(+), 1 deletion(-)

diff --git a/sound/soc/stm/stm32_spdifrx.c b/sound/soc/stm/stm32_spdifrx.c
index b4c3d983e195..aa83b50efabb 100644
--- a/sound/soc/stm/stm32_spdifrx.c
+++ b/sound/soc/stm/stm32_spdifrx.c
@@ -845,7 +845,8 @@ static struct snd_soc_dai_driver stm32_spdifrx_dai[] = {
 static const struct snd_pcm_hardware stm32_spdifrx_pcm_hw = {
 	.info = SNDRV_PCM_INFO_INTERLEAVED | SNDRV_PCM_INFO_MMAP,
 	.buffer_bytes_max = 8 * PAGE_SIZE,
-	.period_bytes_max = 2048, /* MDMA constraint */
+	.period_bytes_min = 1024,
+	.period_bytes_max = 4 * PAGE_SIZE,
 	.periods_min = 2,
 	.periods_max = 8,
 };
-- 
2.7.4