[PATCH 1/2] ALSA: usb-audio: name the interfaces of the Steinberg UR22C

[Xinyu Wei]

Configuration 2 of the Steinberg UR22C (0499:172f) exposes 6 playback
and 8 capture channels over standard UAC2 descriptors with
bInterfaceClass set to 0xFF.

Because the interfaces are vendor-class, they fall into the Yamaha
catch-all entry and QUIRK_AUTODETECT fails to set them up:
create_auto_pcm_quirk() rejects 6-byte UAC2 format descriptors, and
interface 0 (audiocontrol, 1 altsetting, 0 endpoints) is rejected by
both auto-PCM and auto-MIDI paths, leaving interfaces 0-2 unbound with
no PCM registered.

Add a USB_DEVICE_VENDOR_SPEC composite entry before the Yamaha catch-all:
 - interface 0: QUIRK_DATA_STANDARD_MIXER
 - interfaces 1, 2: QUIRK_DATA_STANDARD_AUDIO (6-ch playback, 8-ch capture)
 - interfaces 3, 4: QUIRK_DATA_MIDI_YAMAHA (DIN MIDI and DSP mixer
   control; both carry Yamaha-style CS_INTERFACE jack descriptors with
   no CS_ENDPOINT descriptor)

Configuration 1 uses bInterfaceClass 0x01 and is unaffected.  The
existing IMPLICIT_FB_FIXED_DEV(0x0499, 0x172f, 0x81, 2) entry in
implicit.c applies to both configurations unchanged.

Signed-off-by: Xinyu Wei <xinyuwei1024@xxxxxxxxx>
---
 sound/usb/quirks-table.h | 14 ++++++++++++++
 1 file changed, 14 insertions(+)

diff --git a/sound/usb/quirks-table.h b/sound/usb/quirks-table.h
index e85eeb536..cc2c1317a 100644
--- a/sound/usb/quirks-table.h
+++ b/sound/usb/quirks-table.h
@@ -455,6 +455,20 @@ YAMAHA_DEVICE(0x7000, "DTX"),
 YAMAHA_DEVICE(0x7010, "UB99"),
 #undef YAMAHA_DEVICE
 #undef YAMAHA_INTERFACE
+/* Steinberg UR22C (configuration 2) */
+{
+	USB_DEVICE_VENDOR_SPEC(0x0499, 0x172f),
+	QUIRK_DRIVER_INFO {
+		QUIRK_DATA_COMPOSITE {
+			{ QUIRK_DATA_STANDARD_MIXER(0) },
+			{ QUIRK_DATA_STANDARD_AUDIO(1) },
+			{ QUIRK_DATA_STANDARD_AUDIO(2) },
+			{ QUIRK_DATA_MIDI_YAMAHA(3) },
+			{ QUIRK_DATA_MIDI_YAMAHA(4) },
+			QUIRK_COMPOSITE_END
+		}
+	}
+},
 /* this catches most recent vendor-specific Yamaha devices */
 {
 	.match_flags = USB_DEVICE_ID_MATCH_VENDOR |
-- 
2.56.0