ALSA: pcm - Use UNKNOWN chmap for mono streams

In general, mono streams have no dedicated speaker assignment, thus
they should be rather marked as UNKNOWN position.

Signed-off-by: Takashi Iwai <tiwai@suse.de>

diff --git a/sound/core/pcm_lib.c b/sound/core/pcm_lib.c
index 0a750ec..9647a22 100644 (file)
--- a/sound/core/pcm_lib.c
+++ b/sound/core/pcm_lib.c
@@ -2311,7 +2311,7 @@ EXPORT_SYMBOL(snd_pcm_lib_readv);
 /* default channel maps for multi-channel playbacks, up to 8 channels */
 const struct snd_pcm_chmap_elem snd_pcm_std_chmaps[] = {
        { .channels = 1,
-         .map = { SNDRV_CHMAP_FC } },
+         .map = { SNDRV_CHMAP_UNKNOWN } },
        { .channels = 2,
          .map = { SNDRV_CHMAP_FL, SNDRV_CHMAP_FR } },
        { .channels = 4,
@@ -2333,7 +2333,7 @@ EXPORT_SYMBOL_GPL(snd_pcm_std_chmaps);
 /* alternative channel maps with CLFE <-> surround swapped for 6/8 channels */
 const struct snd_pcm_chmap_elem snd_pcm_alt_chmaps[] = {
        { .channels = 1,
-         .map = { SNDRV_CHMAP_FC } },
+         .map = { SNDRV_CHMAP_UNKNOWN } },
        { .channels = 2,
          .map = { SNDRV_CHMAP_FL, SNDRV_CHMAP_FR } },
        { .channels = 4,