• Takashi Iwai's avatar
    ALSA: usb-audio: Fix last interface check for registration · 39efc9c8
    Takashi Iwai authored
    The recent fix in commit 6392dcd1 ("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: 6392dcd1 ("ALSA: usb-audio: Register card at the last interface")
    Link: https://lore.kernel.org/r/20220915085947.7922-1-tiwai@suse.de
    
    Signed-off-by: default avatarTakashi Iwai <tiwai@suse.de>
    39efc9c8
card.c 32.3 KB