The device name

[Yuka Muromachi]

Hi:

I'm trying to written Azalia (HD Audio) support for freebsd now.
The controller part is working, I'm trying to add codec support now.

There is a question:

most sound device attach function will call those two line to create
/dev/audio* , /dev/dsp*, /dev/dspW* and /dev/dspr*:

pcm_addchan(dev, PCMDIR_REC, &ad1816chan_class, ad1816);
pcm_addchan(dev, PCMDIR_PLAY, &ad1816chan_class, ad1816);

pcm_addchan() will call pcm_chn_add()

But, I do not understand, why direction = PCMDIR_REC
will still create one more /dev/audio , /dev/dspW, /dev/dspr 
device?

My mean, that code will create /dev/audio0.0 /dev/audio0.1 ...
and /dev/dspr0.0