for (idx = 0; idx < 2; idx++) {
subs = &as->substream[idx];
if (!subs->num_formats)
- return;
+ continue;
snd_usb_release_substream_urbs(subs, 1);
subs->interface = -1;
}
}
switch (protocol) {
+ default:
+ snd_printdd(KERN_WARNING "unknown interface protocol %#02x, assuming v1\n",
+ protocol);
+ /* fall through */
+
case UAC_VERSION_1: {
struct uac1_ac_header_descriptor *h1 = control_header;
break;
}
-
- default:
- snd_printk(KERN_ERR "unknown protocol version 0x%02x\n", protocol);
- return -EINVAL;
}
return 0;
goto __error;
}
- chip->ctrl_intf = alts;
+ /*
+ * For devices with more than one control interface, we assume the
+ * first contains the audio controls. We might need a more specific
+ * check here in the future.
+ */
+ if (!chip->ctrl_intf)
+ chip->ctrl_intf = alts;
if (err > 0) {
/* create normal USB audio interfaces */