Module device mapping options
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Systems can have two PCM and/or MIDI devices. Usually, the first PCM
device (hw:0,0 in ALSA) is mapped to /dev/dsp0 and the secondary
device (hw:0,1) to /dev/adsp0 (if available). For MIDI, /dev/midi0
and /dev/amidi0 for the first and second devices, respectively.
You can change this device mapping via the module options for snd-pcm-oss and snd-rawmidi
The following options are available for snd-pcm-oss:
dsp_map-- the PCM device number assigned to/dev/dspX(default = 0)adsp_map-- PCM device number assigned to/dev/adspX(default = 1)
For example, to map the third PCM device (hw:0,2) to /dev/adsp0, do
like this:
options snd-pcm-oss adsp_map=2
(need more here; where does the above line get put? somewhere in
/etc/modutils.d?)
The options take arrays. For configuring the second card, specify two
entries separated by comma. For example, to map the third PCM device on
the second card to /dev/adsp1, define like below:
options snd-pcm-oss adsp_map=0,2
To change the mapping of MIDI devices, the following options are available for snd-rawmidi:
midi_map-- MIDI device number assigned to/dev/midi0X(default = 0)amidi_map-- MIDI device number assigned to/dev/amidi0X(default = 1)
For example, to assign the third MIDI device on the first card to
/dev/midi00, define as follows:
options snd-rawmidi midi_map=2
Retrieved from "http://alsa.opensrc.org/Module_device_mapping_options"