This one line change gets MIDI communication flowing between ALSA and the Boss MS-3 multi-effect switcher.
///// *** sound/usb/midi.c 2023-08-10 22:46:31.016346930 +0200 --- sound/usb/midi.c-orig 2023-07-19 16:37:03.000000000 +0200 *************** *** 2106,2113 **** struct usb_endpoint_descriptor *epd; int i, out_eps = 0, in_eps = 0;
! if (USB_ID_VENDOR(umidi->usb_id) == 0x0582 && ! USB_ID_PRODUCT(umidi->usb_id) != 0x01f5) snd_usbmidi_switch_roland_altsetting(umidi);
if (endpoint[0].out_ep || endpoint[0].in_ep) --- 2106,2112 ---- struct usb_endpoint_descriptor *epd; int i, out_eps = 0, in_eps = 0;
! if (USB_ID_VENDOR(umidi->usb_id) == 0x0582) snd_usbmidi_switch_roland_altsetting(umidi);
if (endpoint[0].out_ep || endpoint[0].in_ep)
/////
There are doubtless other Roland/Boss USB_ID_PRODUCT id's that are effected and it would be nice to make the USB_ID_PRODUCT value a tunable, but that is beyond my competence.