Linux MIDI support

[kmtaylor]

Well, I'm new to this board (Just purchased a Juno Gi on Thursday, my first synth). I'm absolutely loving it.

I've just started playing with MIDI, and was happy to see that MIDI over USB is supported.

For linux users, the device isn't recognised, however support is there. The following patch informs snd_usb_audio that the Juno Gi is MIDI capable:

Hope this is useful for someone.

(Quirks-table is in linux/sound/usb)

Code: Select all

--- quirks-table.h.old	2012-05-30 11:13:42.000000000 +1000
+++ quirks-table.h	2012-05-30 11:13:50.000000000 +1000
@@ -1400,6 +1400,19 @@
 	}
 },
 {
+	USB_DEVICE(0x582, 0x0123),
+	.driver_info = (unsigned long) & (const struct snd_usb_audio_quirk) {
+		.vendor_name = "Roland",
+		.product_name = "Juno-Gi",
+		.ifnum = -1,
+		.type = QUIRK_MIDI_FIXED_ENDPOINT,
+		.data = & (const struct snd_usb_midi_endpoint_info) {
+			.out_cables = 0x0001,
+			.in_cables  = 0x0001
+		}
+	}
+},
+{
 	/* Roland SH-201 */
 	USB_DEVICE(0x0582, 0x00ad),
 	.driver_info = (unsigned long) & (const struct snd_usb_audio_quirk) {

[ecceccecc]

How do I make this patch work? I have a Juno-Gi and Kubuntu 12.04 64-bit.

[kmtaylor]

Hi,

You'll need to install one of the linux source packages. (Look them up for your distribution, I think debian derived distributions use the "linux-headers-[version]" naming scheme).

Then patch /usr/src/linux-[version]/sound/usb/quirks-table.h using:
patch -p0 < [The above patch] while in the /usr/src/linux-[version]/sound/usb/ directory.

Then compile your kernel (there are plenty of tutorials on the web for this) install it and you should be ready to go.

[ecceccecc]

Complicated... But if there's currently the only one solution, I have to try it. But it's funny that Juno-Di can use a "generic" USB MIDI driver (as someone said in the Juno-Di forum section) and Juno-Gi can't do that... Or at least I don't found the setting, maybe...

[kmtaylor]

It's just that the Gi has a different USB-ID and it hasn't been incorporated into ALSA yet.

Regarding complexity: Running linux/roland gear is not too bad, but if you're new, it can be a steepish learning curve. _Definitely_ worth it in the long run (in my opinion!). There is a lot of great software out there. I would recommend getting started with Ardour. I've had a great experience with it. Also the jack-audio-connection-kit is a wonderful tool and will make life much easier. Good luck.

Also note, that the Di does have a 'generic driver' mode while the Gi does not. (Meaning that it reports itself as an 'audio' class device with midi endpoints.) Doesn't really matter once you've updated quirks-table.h.