ALSA: usb-audio: Allow multiple entries for the same iface in composite quirk

Currently the composite quirk doesn't work when multiple entries are
assigned to the same interface because it marks the interface as
claimed then checks whether the interface has been already claimed for
the secondary entry.  But, if you look at the code, you'll notice that
multiple entries are allowed if the entry is the current interface;
i.e. the current behavior is anyway inconsistent, and this is an
unintended shortcoming.

This patch fixes the problem by marking the relevant interfaces as
claimed after applying the all composite entries.  This fix will be
needed for the upcoming enhancements for Digidesign Mbox 1 quirks.

Reviewed-by: Clemens Ladisch <clemens@ladisch.de>
Signed-off-by: Takashi Iwai <tiwai@suse.de>

diff --git a/sound/usb/quirks.c b/sound/usb/quirks.c
index d2aa45a..e9ff3a6 100644 (file)
--- a/sound/usb/quirks.c
+++ b/sound/usb/quirks.c
@@ -58,9 +58,17 @@ static int create_composite_quirk(struct snd_usb_audio *chip,
                err = snd_usb_create_quirk(chip, iface, driver, quirk);
                if (err < 0)
                        return err;
-               if (quirk->ifnum != probed_ifnum)
+       }
+
+       for (quirk = quirk->data; quirk->ifnum >= 0; ++quirk) {
+               iface = usb_ifnum_to_if(chip->dev, quirk->ifnum);
+               if (!iface)
+                       continue;
+               if (quirk->ifnum != probed_ifnum &&
+                   !usb_interface_claimed(iface))
                        usb_driver_claim_interface(driver, iface, (void *)-1L);
        }
+
        return 0;
 }