ALSA: hda: Fix the control element identification for multiple codecs
authorJaroslav Kysela <perex@perex.cz>
Thu, 2 Feb 2023 09:20:13 +0000 (10:20 +0100)
committerTakashi Iwai <tiwai@suse.de>
Fri, 3 Feb 2023 16:19:20 +0000 (17:19 +0100)
commitd045bceff5a904bd79d71dede9f927c00ce4906f
tree2f26ead820165b7b0cffa2df3bfb2ccc444c6322
parent372a0d7856be29671fc03e2f28ac27114e8c6805
ALSA: hda: Fix the control element identification for multiple codecs

Some motherboards have multiple HDA codecs connected to the serial bus.
The current code may create multiple mixer controls with the almost
identical identification.

The current code use id.device field from the control element structure
to store the codec address to avoid such clashes for multiple codecs.
Unfortunately, the user space do not handle this correctly. For mixer
controls, only name and index are used for the identifiers.

This patch fixes this problem to compose the index using the codec
address as an offset in case, when the control already exists. It is
really unlikely that one codec will create 10 similar controls.

This patch adds new kernel module parameter 'ctl_dev_id' to allow
select the old behaviour, too. The CONFIG_SND_HDA_CTL_DEV_ID Kconfig
option sets the default value.

BugLink: https://github.com/alsa-project/alsa-lib/issues/294
BugLink: https://github.com/alsa-project/alsa-lib/issues/205
Fixes: 54d174031576 ("[ALSA] hda-codec - Fix connection list parsing")
Fixes: 1afe206ab699 ("ALSA: hda - Try to find an empty control index when it's occupied")
Signed-off-by: Jaroslav Kysela <perex@perex.cz>
Link: https://lore.kernel.org/r/20230202092013.4066998-1-perex@perex.cz
Signed-off-by: Takashi Iwai <tiwai@suse.de>
include/sound/hda_codec.h
sound/pci/hda/Kconfig
sound/pci/hda/hda_codec.c
sound/pci/hda/hda_controller.c
sound/pci/hda/hda_controller.h
sound/pci/hda/hda_intel.c