}
host_iface = &usb_ifnum_to_if(chip->dev, ctrlif)->altsetting[0];
- mixer->protocol = host_iface->desc.bInterfaceProtocol;
+ mixer->protocol = get_iface_desc(host_iface)->bInterfaceProtocol;
if ((err = snd_usb_mixer_controls(mixer)) < 0 ||
(err = snd_usb_mixer_status_create(mixer)) < 0)