Re: Experimental USB audio support

[Patrick Shirkey <pshirkey@boosthardware.com>]

Takashi Iwai wrote:
> 
> At Fri, 31 May 2002 20:55:01 +0900,
> Patrick Shirkey wrote:
> >
> > Takashi Iwai wrote:
> > >
> > > now a new version is cvs.  it dumps the descriptor at
> > > /proc/asound/cardX/descriptor.  if the cvs servers is not sync'ed,
> > > please let me know.  i'll send you a patch.
> > >
> >
> > With this patch there is *alot * more info in lsusb. Excellent work.
> 
> as you already know, it's not me but the update of usb modules :)
> 
> anyway, could you check again whether the driver works?
> just taking a look at the lsusb output, the device has no mixer units.
> there are only input/output terminals.
> so, don't be bothered even if you see no mixer controls.
> 
> Takashi

So far I cannot get sound out using

 cat /bin/bash > dev/dsp2
 aplay -D hw:2,0 -f cd some.wav

both return with device does not exist or similar

The same for recording.

arecord -D hw:2,0 -f cd  -d 10 /art/code/alsa/test.wav
ALSA lib pcm_hw.c:797:(snd_pcm_hw_open) open /dev/snd/pcmC2D0c failed:
No such file or directory
arecord: main:447: audio open error: No such file or directory

---
 ls /dev/snd/
controlC0  controlC3  midiC0D0   pcmC0D1p   pcmC1D0c   
controlC1  controlC4  pcmC0D0c   pcmC0D2c   pcmC1D0p   
controlC2  hwC0D0     pcmC0D0p   pcmC0D2p   timer  
---

Are the pcm devices created by the mixer code? If so then can you use
the descriptor info to hardcode them in?

On a side note I would really like to know how you use the descriptor
info to write a driver. You asked me for the same thing when you were
doing the cmipci driver. It would be a valuable additon to the
developers documentation.

Something like "Using the information provided in /proc/asound to write
a driver". 

If you/Paul/Jaroslav/Abramo or anyone else who grok it could write up
some quick notes I will gladly incorporate them into the online docs.

I am going to write up some info now on the installing the usb-audio
driver and add it to the wiki.


-- 
Patrick Shirkey - Boost Hardware Ltd.
For the discerning hardware connoisseur
Http://www.boosthardware.com
Http://www.boosthardware.com/LAU/guide/
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