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ALSA: usb-audio: Fix last interface check for registration 

commit 39efc9c8a9 upstream.

The recent fix in commit 6392dcd1d0 ("ALSA: usb-audio: Register card
at the last interface") tried to delay the card registration until the
last found interface is probed.  It assumed that the probe callback
gets called for those later interfaces, but it's not always true; as
the driver loops over the descriptor and probes the matching ones,
it's not separately called via multiple probe calls.  This results in
the missing card registration, i.e. no sound device.

For addressing this problem, replace the check whether the last
interface is processed with usb_interface_claimed() instead of the
comparison with the probe interface number.

Fixes: 6392dcd1d0 ("ALSA: usb-audio: Register card at the last interface")
Link: https://lore.kernel.org/r/20220915085947.7922-1-tiwai@suse.de
Signed-off-by: Takashi Iwai <tiwai@suse.de>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
This commit is contained in:
Takashi Iwai 2022-09-15 10:59:47 +02:00 committed by Greg Kroah-Hartman
parent 0ad680a71e
commit 9d4f4dc3cd
1 changed files with 1 additions and 1 deletions
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2
sound/usb/card.c
View File

@ -884,7 +884,7 @@ static int usb_audio_probe(struct usb_interface *intf,
* one given via option
*/
if (check_delayed_register_option(chip) == ifnum ||
chip->last_iface == ifnum) {
usb_interface_claimed(usb_ifnum_to_if(dev, chip->last_iface))) {
err = snd_card_register(chip->card);
if (err < 0)
goto __error;