+static int create_autodetect_quirks(struct snd_usb_audio *chip,
+ struct usb_interface *iface,
+ struct usb_driver *driver,
+ const struct snd_usb_audio_quirk *quirk)
+{
+ int probed_ifnum = get_iface_desc(iface->altsetting)->bInterfaceNumber;
+ int ifcount, ifnum, err;
+
+ err = create_autodetect_quirk(chip, iface, driver);
+ if (err < 0)
+ return err;
+
+ /*
+ * ALSA PCM playback/capture devices cannot be registered in two steps,
+ * so we have to claim the other corresponding interface here.
+ */
+ ifcount = chip->dev->actconfig->desc.bNumInterfaces;
+ for (ifnum = 0; ifnum < ifcount; ifnum++) {
+ if (ifnum == probed_ifnum || quirk->ifnum >= 0)
+ continue;
+ iface = usb_ifnum_to_if(chip->dev, ifnum);
+ if (!iface ||
+ usb_interface_claimed(iface) ||
+ get_iface_desc(iface->altsetting)->bInterfaceClass !=
+ USB_CLASS_VENDOR_SPEC)
+ continue;
+
+ err = create_autodetect_quirk(chip, iface, driver);
+ if (err >= 0)
+ usb_driver_claim_interface(driver, iface, (void *)-1L);
+ }
+
+ return 0;
+}
+