Re: Experimental USB audio support

[Takashi Iwai <tiwai@suse.de>]

Hi Patrick,

At Thu, 30 May 2002 14:15:55 +0900,
Patrick Shirkey wrote:
> 
> As you can tell I'm very excited about this.
> 
> Here's some preliminary stuff.
> 
> #dmesg
> ----
> usb.c: registered new driver audio
> hub.c: USB new device connect on bus1/1, assigned device number 3
> ALSA usbaudio.c:1134: 3:1:1 : AS_GENERAL descriptor not found
> ALSA usbaudio.c:1134: 3:2:1 : AS_GENERAL descriptor not found

looks like some interfaces don't have AS_GENERAL descriptor, which
specifies the pcm formats to be supported.  anyway detailed
description list from lsusb is necessary for analyse.


> devfs: devfs_register(): device already registered: "unknown"
> ALSA usbaudio.c:1191: 3:4:1 : frame size 3 doesn't match ALSA 24bit
> sample format

oh, that's interesting.  apparently the device uses 3 bytes for 24bit
sample format.  alsa supports only 4bytes-packed format, so far.
that's not expected.


> devfs: devfs_register(): device already registered: "unknown"

this is a bug of sound_core.c.  you can fix it by replacing
sound_core.c with the one in alsa-kernel tree.


> ----
>  more /proc/asound/cards 
> 0 [card0          ]: CMI8738 - C-Media PCI CMI8738
>                      C-Media PCI CMI8738 (model 37) at 0xa400, irq 5
> 1 [card1          ]: ICH - Intel 82801BA-ICH2
>                      Intel 82801BA-ICH2 at 0xdc00, irq 3
> 2 [card2          ]: USB-Audio - USB Audio Driver
>                      M Audio USB AudioSport Quattro (tm)
> 3 [card3          ]: USB-Audio - USB Audio Driver
>                      M Audio USB AudioSport Quattro (tm)
> 4 [card4          ]: USB-Audio - USB Audio Driver
>                      M Audio USB AudioSport Quattro (tm)

hmm..  do you have three devices?  i guess these three duplicated
entries are bogus...

> # lsusb -p /proc/asound/card2/ -vv
> # lsusb -p /proc/asound/card3/ -vv
> # lsusb -p /proc/asound/card4/ -vv
> # lsusb -p /proc/asound/card4/ -vv -t
> cannot open /proc/asound/card4//devices, No such file or directory (2)

just run lsusb (as root) without options.  then it will list all
devices out.  or, you can specify the vendor and device ids per -d
option.  please send me the output.


Takashi

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