ALSA: usb-audio: Use fixed control index for us16x08 mixer elements

The callbacks for us16x08 mixer elements assume that id.index points
to the channel to be operated, and the assumption is correct for now.
However, since the kctls are added via snd_usb_mixer_add_control() and
it looks for the empty slot if the same control name is already
present, in theory, the index can become more than the channel numbers
(if a conflicting name really happens).

Since the mixer code in us16x08 doesn't need the search for an empty
slot but requires the fixed index, this patch changes slightly how to
assign the kcontrols.  Now, a new argument is added to
snd_usb_mixer_add_list() in order to disable the empty slot search,
and use it in us16x08's add_new_ctl() helper function, instead.

Fixes: d2bb390a2081 ("ALSA: usb-audio: Tascam US-16x08 DSP mixer quirk")
Reported-by: Sashiko <sashiko-bot@kernel.org>
Link: https://patch.msgid.link/20261014061406.162938-1-tiwai@suse.de
Signed-off-by: Takashi Iwai <tiwai@suse.de>

0 files changed, 0 insertions, 0 deletions