From 210e6a844112bd7e28a04faedac677918e1f3040 Mon Sep 17 00:00:00 2001 From: Takashi Iwai Date: Sun, 16 Jun 2024 09:34:46 +0200 Subject: [PATCH] ALSA: chmap: Mark Channel Map controls as volatile 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 Closes: https://lore.kernel.org/r/1d44be36-9bb9-4d82-8953-5ae2a4f09405@molgen.mpg.de Reviewed-by: Jaroslav Kysela Signed-off-by: Takashi Iwai Link: https://lore.kernel.org/20240616073454.16512-6-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,