[linux-audio-user] edirol um-880 configuration help needed

[Pedro Lopez-Cabanillas]

Chris Pickett wrote:
> > Clemens Ladisch wrote:
> >>CONFIG_USB_MIDI is not the ALSA driver but the old OSS driver.
> >>You want to use CONFIG_SND_USB_AUDIO instead.
> >
> > Regardless of whether or not CONFIG_SND_USB_AUDIO is a module, I now
> > only get:
> >
> > usb 1-1: new full speed USB device using address 2
> >
> > in /var/log/messages.  'modprobe snd-usb-audio vid=0x0582 pid=0x0015'
> > doesn't help the situation.  'amidi -l' only shows me my Crystal
> > SoundFusion card.
> >
> >>The ALSA driver supports both driver modes.
>
> I tried switching the UM-880 back to the FPT mode, and it works now.  I
> don't know if that's a regression, but in any case I'll try out patches
> for you if it's something you want to fix.

The "generic driver mode" descriptors aren't fully compliant with the USB MIDI 
specification, because it doesn't have an AudioControl interface, which is 
mandatory. You can say that an AudioControl interface is meaningless here 
because the UM-880 has no audio function incorporated, only MIDI. That is 
true, but in this case the class-specific AC interface descriptor will only 
contain the header descriptor. Did you see a kernel/syslog complain about  
"cannot find HEADER" or something like that? 

The usb-midi OSS driver doesn't look for AC descriptor, so it can handle it. 
But as Clemens said, that driver is not supported by Rosegarden.

Regards,
Pedro