[PATCH 17/29] staging: bcm2835-audio: Add 10ms period constraint

From: Takashi Iwai
Date: Tue Sep 04 2018 - 12:00:25 EST


It seems that the resolution of vc04 callback is in 10 msec; i.e. the
minimal period size is also 10 msec.

This patch adds the corresponding hw constraint.

Signed-off-by: Takashi Iwai <tiwai@xxxxxxx>
---
drivers/staging/vc04_services/bcm2835-audio/bcm2835-pcm.c | 5 +++++
1 file changed, 5 insertions(+)

diff --git a/drivers/staging/vc04_services/bcm2835-audio/bcm2835-pcm.c b/drivers/staging/vc04_services/bcm2835-audio/bcm2835-pcm.c
index 9659c25b9f9d..6d89db6e14e4 100644
--- a/drivers/staging/vc04_services/bcm2835-audio/bcm2835-pcm.c
+++ b/drivers/staging/vc04_services/bcm2835-audio/bcm2835-pcm.c
@@ -145,6 +145,11 @@ static int snd_bcm2835_playback_open_generic(
SNDRV_PCM_HW_PARAM_PERIOD_BYTES,
16);

+ /* position update is in 10ms order */
+ snd_pcm_hw_constraint_minmax(runtime,
+ SNDRV_PCM_HW_PARAM_PERIOD_TIME,
+ 10 * 1000, UINT_MAX);
+
chip->alsa_stream[idx] = alsa_stream;

chip->opened |= (1 << idx);
--
2.18.0