The values returned from Playback Channel Map and Capture Channel Map controls may vary dynamically depending on the corresponding PCM stream. Mark those as volatile to indicate the values are unstable and not suitable for testing.
Note that we may change the driver to return -EINVAL, but this would bring other side effects, such as "alsactl restore" would start receiving unexpected errors. So we still keep returning 0 for those invalid inputs.
Reported-by: Paul Menzel pmenzel@molgen.mpg.de Closes: https://lore.kernel.org/r/1d44be36-9bb9-4d82-8953-5ae2a4f09405@molgen.mpg.de Reviewed-by: Jaroslav Kysela perex@perex.cz Signed-off-by: Takashi Iwai tiwai@suse.de --- sound/core/pcm_lib.c | 1 + 1 file changed, 1 insertion(+)
diff --git a/sound/core/pcm_lib.c b/sound/core/pcm_lib.c index 6f73b3c2c205..071c67cbc479 100644 --- a/sound/core/pcm_lib.c +++ b/sound/core/pcm_lib.c @@ -2556,6 +2556,7 @@ int snd_pcm_add_chmap_ctls(struct snd_pcm *pcm, int stream, struct snd_kcontrol_new knew = { .iface = SNDRV_CTL_ELEM_IFACE_PCM, .access = SNDRV_CTL_ELEM_ACCESS_READ | + SNDRV_CTL_ELEM_ACCESS_VOLATILE | SNDRV_CTL_ELEM_ACCESS_TLV_READ | SNDRV_CTL_ELEM_ACCESS_TLV_CALLBACK, .info = pcm_chmap_ctl_info,