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 <[email protected]> --- 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
