[ALSA] at73c213: Add constraints for periods value
The interrupt handler always provide runtime->period_size data, so it
works correctly only if buffer_size was a multiple of period_size.
This patch fixes periodic click noise.
Signed-off-by: Atsushi Nemoto <anemo@mba.ocn.ne.jp>
Signed-off-by: Takashi Iwai <tiwai@suse.de>
diff --git a/sound/spi/at73c213.c b/sound/spi/at73c213.c
index aa57115..09802e8 100644
--- a/sound/spi/at73c213.c
+++ b/sound/spi/at73c213.c
@@ -210,7 +210,13 @@
{
struct snd_at73c213 *chip = snd_pcm_substream_chip(substream);
struct snd_pcm_runtime *runtime = substream->runtime;
+ int err;
+ /* ensure buffer_size is a multiple of period_size */
+ err = snd_pcm_hw_constraint_integer(runtime,
+ SNDRV_PCM_HW_PARAM_PERIODS);
+ if (err < 0)
+ return err;
snd_at73c213_playback_hw.rate_min = chip->bitrate;
snd_at73c213_playback_hw.rate_max = chip->bitrate;
runtime->hw = snd_at73c213_playback_hw;