[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 <[email protected]> Signed-off-by: Takashi Iwai <[email protected]>
kishon · Apr 24, 2008 · f5e09ef · f5e09ef
1 parent b32300a
commit f5e09ef
Showing 1 changed file with 6 additions and 0 deletions.
diff --git a/sound/spi/at73c213.c b/sound/spi/at73c213.c
@@ -210,7 +210,13 @@ static int snd_at73c213_pcm_open(struct snd_pcm_substream *substream)
 {
 	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;