[alsa-devel] [PATCH] pcm: Fix channel map query when there are lots of maps

[Anssi Hannula]

On most HDA Intel HDMI devices, the channel map list is approx. 500 ints
in size, making the 256-sized buffer used by
snd_pcm_query_chmaps_from_hw() too small and causing the query to fail
(NULL result to caller, ENOMEM).

Bump the buffer size to 2048 ints.

Signed-off-by: Anssi Hannula <anssi.hannula at iki.fi>
---

Found while writing XBMC support.

I don't like just bumping the buffer size, so I hope you have some idea
of a better solution?
I guess one way would be just to retry with a dynamically allocated
bigger buffer on ENOMEM, if there is nothing better...

 src/pcm/pcm_hw.c | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/src/pcm/pcm_hw.c b/src/pcm/pcm_hw.c
index 9ff83a9..ed83197 100644
--- a/src/pcm/pcm_hw.c
+++ b/src/pcm/pcm_hw.c
@@ -1051,7 +1051,7 @@ snd_pcm_query_chmaps_from_hw(int card, int dev, int subdev,
 {
 	snd_ctl_t *ctl;
 	snd_ctl_elem_id_t *id;
-	unsigned int tlv[256], *start;
+	unsigned int tlv[2048], *start;
 	snd_pcm_chmap_query_t **map;
 	int i, ret, nums;
 
-- 
1.8.4.5