MPU-401 MIDI setup (Howto)

From the ALSA wiki

How to get the MIDI-Port of the VIA8233 working

You'll need the 'snd-mpu401' driver module. If you don't have it already, recompile alsa with it. Now edit your modules.conf file and add these lines (get the irq and io port from your bios or windows):

alias snd-card-1 snd-mpu401
options snd-mpu401 port=0x330 irq=7
alias sound-slot-1 snd-card-1
alias sound-service-1-0 snd-mixer-oss
alias sound-service-1-1 snd-seq-oss
alias sound-service-1-3 snd-pcm-oss
alias sound-service-1-12 snd-pcm-oss

Note that you might have to replace port and irq by snd_port and snd_irq, respectively, depending on your kernel version. Type modinfo snd-mpu401 to get the list of parameters supported by snd-mpu401. Now do a modprobe snd-mpu401. It should load without errors. Now check the /proc/asound/oss/sndstat file and you should see something like this under Midi-Devices:

1: MPU-401 (UART)

That's it! Have fun :) (for example, read Takashi's HowTo? about TiMidity as an ALSA-Sequencer-Client and then connect a MIDI-Keyboard to your MIDI-Port and you'll be able to play on it!)