[alsa-devel] [PATCH 1/3] ALSA: Fix handling of multiple msbits constraints on the same runtime

[Lars-Peter Clausen]

If the sound card is made up of discrete components, each with their own
driver (e.g. like in the ASoC case), we might end up with multiple msbits
constraint rules installed. Currently this will result in msbits being set
to whatever the last rule set it to.

This patch updates the behavior of the rule to choose the minimum (other
than zero) of all the installed rules.

Signed-off-by: Lars-Peter Clausen <lars at metafoo.de>
---
 sound/core/pcm_lib.c | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/sound/core/pcm_lib.c b/sound/core/pcm_lib.c
index ec9e786..b0c1535 100644
--- a/sound/core/pcm_lib.c
+++ b/sound/core/pcm_lib.c
@@ -1300,7 +1300,7 @@ static int snd_pcm_hw_rule_msbits(struct snd_pcm_hw_params *params,
 	unsigned int msbits = l >> 16;
 	struct snd_interval *i = hw_param_interval(params, SNDRV_PCM_HW_PARAM_SAMPLE_BITS);
 	if (snd_interval_single(i) && snd_interval_value(i) == width)
-		params->msbits = msbits;
+		params->msbits = min_not_zero(params->msbits, msbits);
 	return 0;
 }
 
-- 
1.8.0