[alsa-devel] [PATCH] ALSA: usb-audio: Add MIDI support for Steinberg MI2/MI4

[Dominic Sacré]

The Steinberg MI2 and MI4 interfaces are compatible with the USB class
audio spec, but the MIDI part of the devices is reported as a vendor
specific interface.

This patch adds entries to quirks-table.h to recognize the MIDI
endpoints. Audio functionality was already working and is unaffected by
this change.

Signed-off-by: Dominic Sacré <dominic.sacre at gmx.de>
Signed-off-by: Albert Huitsing <albert at huitsing.nl>
---
 sound/usb/quirks-table.h | 43 +++++++++++++++++++++++++++++++++++++++++++
 1 file changed, 43 insertions(+)

diff --git a/sound/usb/quirks-table.h b/sound/usb/quirks-table.h
index 2f6d3e9..304c02a 100644
--- a/sound/usb/quirks-table.h
+++ b/sound/usb/quirks-table.h
@@ -3152,6 +3152,49 @@ AU0828_DEVICE(0x2040, 0x7270, "Hauppauge", "HVR-950Q"),
 },
 
 {
+	/* Steinberg MI2 */
+	USB_DEVICE_VENDOR_SPEC(0x0a4e, 0x2040),
+	.driver_info = (unsigned long) & (const struct snd_usb_audio_quirk) {
+		.ifnum = QUIRK_ANY_INTERFACE,
+		.type = QUIRK_COMPOSITE,
+		.data = & (const struct snd_usb_audio_quirk[]) {
+			{
+				.ifnum = 3,
+				.type = QUIRK_MIDI_FIXED_ENDPOINT,
+				.data = &(const struct snd_usb_midi_endpoint_info) {
+					.out_cables = 0x0001,
+					.in_cables  = 0x0001
+				}
+			},
+			{
+				.ifnum = -1
+			}
+		}
+	}
+},
+{
+	/* Steinberg MI4 */
+	USB_DEVICE_VENDOR_SPEC(0x0a4e, 0x4040),
+	.driver_info = (unsigned long) & (const struct snd_usb_audio_quirk) {
+		.ifnum = QUIRK_ANY_INTERFACE,
+		.type = QUIRK_COMPOSITE,
+		.data = & (const struct snd_usb_audio_quirk[]) {
+			{
+				.ifnum = 3,
+				.type = QUIRK_MIDI_FIXED_ENDPOINT,
+				.data = &(const struct snd_usb_midi_endpoint_info) {
+					.out_cables = 0x0001,
+					.in_cables  = 0x0001
+				}
+			},
+			{
+				.ifnum = -1
+			}
+		}
+	}
+},
+
+{
 	/*
 	 * Some USB MIDI devices don't have an audio control interface,
 	 * so we have to grab MIDI streaming interfaces here.
-- 
2.4.4