[linux-audio-user] Re: Edirol UM-1S weird behaviour

Pedro Lopez-Cabanillas plcl at telefonica.net
Mon Nov 22 15:03:31 EST 2004

On Monday 22 November 2004 19:26, Christoph Eckert wrote:
> > Check to make sure that it is indeed alsa which is running
> > (one USB driver covers both audio and MIDI). If need be,
> > "blanklist" the OSS USB drivers.
> Hm, currently I do not know by myself how to do so, but I'll
> figure this out the next days. Is it save to deactivate all
> OSS support in general in the kernel config, or will this
> cause the ALSA OSS emulation to be not working?

You have two kernel drivers for USB MIDI devices.
* 'snd-usb-audio' is the ALSA module containing the drivers for Audio and MIDI 
USB devices.
* 'usb-midi' is the OSS/Free module for USB MIDI devices only.
* 'audio' is the OSS/Free module for USB Audio devices.
You can have both modules compiled and installed, but you should only use one 
of them at a time. ALSA does not need the OSS/Free modules. It can do OSS 
emulation using it's own resources.

Both drivers want to be loaded and claim the device if you have hotplug 
installed. To "blacklist" one of them, insert a line with the module name in 
the file /etc/hotplug/blacklist. Something like this:

[~]$ cat /etc/hotplug/blacklist
# Listing a module here prevents the hotplug scripts from loading it.
# Usually that'd be so that some other driver will bind it instead,
# no matter which driver happens to get probed first.  Sometimes user
# mode tools can also control driver binding.
# Syntax:  driver name alone (without any spaces) on a line. Other
# lines are ignored.

# uhci ... usb-uhci handles the same pci class

# tulip ... de4x5, xircom_tulip_cb, dmfe (...) handle same devices
# At least 2.4.3 and later xircom_tulip doesn't have that conflict
# xircom_tulip_cb


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