force snd-usb-audio to use "Vendor Specific Class"

force snd-usb-audio to use "Vendor Specific Class"

[Alexey Fisher]

Hallo all,
is there any way to force snd-usb-audio to use some "Vendor Specific
Class" device?
i currently got two webcams from my friends to take a look on. They are
cheep gspca based webcams with Mic. I wont to test if snd-usb-audio can
use it if i force it. Devices it self do not provide any hints for the
driver.

lsusb -vd 093a:2468 | grep -i class
  bDeviceClass          255 Vendor Specific Class
  bDeviceSubClass       255 Vendor Specific Subclass
      bInterfaceClass       255 Vendor Specific Class
      bInterfaceSubClass    255 Vendor Specific Subclass
      bInterfaceClass       255 Vendor Specific Class
      bInterfaceSubClass    255 Vendor Specific Subclass
      bInterfaceClass       255 Vendor Specific Class
      bInterfaceSubClass    255 Vendor Specific Subclass
      bInterfaceClass       255 Vendor Specific Class
      bInterfaceSubClass    255 Vendor Specific Subclass
      bInterfaceClass       255 Vendor Specific Class
      bInterfaceSubClass    255 Vendor Specific Subclass
      bInterfaceClass       255 Vendor Specific Class
      bInterfaceSubClass    255 Vendor Specific Subclass
      bInterfaceClass       255 Vendor Specific Class
      bInterfaceSubClass    255 Vendor Specific Subclass
      bInterfaceClass       255 Vendor Specific Class
      bInterfaceSubClass    255 Vendor Specific Subclass
      bInterfaceClass       255 Vendor Specific Class
      bInterfaceSubClass    255 Vendor Specific Subclass

regards,
Alexey

Re: force snd-usb-audio to use "Vendor Specific Class"

[Daniel Mack]

On Wed, Jun 23, 2010 at 03:29:25PM +0200, Alexey Fisher wrote:
> is there any way to force snd-usb-audio to use some "Vendor Specific
> Class" device?
> i currently got two webcams from my friends to take a look on. They are
> cheep gspca based webcams with Mic. I wont to test if snd-usb-audio can
> use it if i force it. Devices it self do not provide any hints for the
> driver.

Sure. Just grep for 'bInterfaceProtocol' in sound/usb/* and patch all
places where this field is parsed.

Daniel

Re: force snd-usb-audio to use "Vendor Specific Class"

[Daniel Mack]

On Wed, Jun 23, 2010 at 03:36:40PM +0200, Daniel Mack wrote:
> On Wed, Jun 23, 2010 at 03:29:25PM +0200, Alexey Fisher wrote:
> > is there any way to force snd-usb-audio to use some "Vendor Specific
> > Class" device?
> > i currently got two webcams from my friends to take a look on. They are
> > cheep gspca based webcams with Mic. I wont to test if snd-usb-audio can
> > use it if i force it. Devices it self do not provide any hints for the
> > driver.
> 
> Sure. Just grep for 'bInterfaceProtocol' in sound/usb/* and patch all
> places where this field is parsed.

Sorry, I got you wrong. I think you should just need an extra entry in
quirks-table.h and quirks.c - other devices do similar things already.

Daniel

Re: force snd-usb-audio to use "Vendor Specific Class"

[Hans de Goede]

Hi,

On 06/23/2010 03:29 PM, Alexey Fisher wrote:
> Hallo all,
> is there any way to force snd-usb-audio to use some "Vendor Specific
> Class" device?
> i currently got two webcams from my friends to take a look on. They are
> cheep gspca based webcams with Mic. I wont to test if snd-usb-audio can
> use it if i force it. Devices it self do not provide any hints for the
> driver.
>
> lsusb -vd 093a:2468 | grep -i class
>    bDeviceClass          255 Vendor Specific Class
>    bDeviceSubClass       255 Vendor Specific Subclass
>        bInterfaceClass       255 Vendor Specific Class
>        bInterfaceSubClass    255 Vendor Specific Subclass
>        bInterfaceClass       255 Vendor Specific Class
>        bInterfaceSubClass    255 Vendor Specific Subclass
>        bInterfaceClass       255 Vendor Specific Class
>        bInterfaceSubClass    255 Vendor Specific Subclass
>        bInterfaceClass       255 Vendor Specific Class
>        bInterfaceSubClass    255 Vendor Specific Subclass
>        bInterfaceClass       255 Vendor Specific Class
>        bInterfaceSubClass    255 Vendor Specific Subclass
>        bInterfaceClass       255 Vendor Specific Class
>        bInterfaceSubClass    255 Vendor Specific Subclass
>        bInterfaceClass       255 Vendor Specific Class
>        bInterfaceSubClass    255 Vendor Specific Subclass
>        bInterfaceClass       255 Vendor Specific Class
>        bInterfaceSubClass    255 Vendor Specific Subclass
>        bInterfaceClass       255 Vendor Specific Class
>        bInterfaceSubClass    255 Vendor Specific Subclass
>
> regards,
> Alexey
>


Don't bother, AFAIK these devices which are pixart pac207bca
based do not contain any microphone at all. If they do they usually
have 2 plugs at the end of their cable a usb plug and an analog
one for the mic.

Google for pac207bca datasheet to find a useless datasheet, note
that it does contain a listing of the physical pins of the device,
and notice the lack of any pins to connect a microphone too.

If the pac207 supports a microphone (which I strongly believe
it does not) the mic on these cameras is not a usb audio class
compatible device. The pac207 declares only one interface so
audio data ihas to be handled over the same interface
as the video data. So in order to support the MIC you first need to
find out how it works and then glew an alsa driver onto the
gspca pac207 driver (as only one driver can be bound to a single
usb interface).

Regards,

Hans, the pac207 driver maintainer


p.s.

It would have been helpful if you had contacted me about this, I just
happen to be subscribed to the alsa-devel list too.

Re: force snd-usb-audio to use "Vendor Specific Class"

[Alexey Fisher]

Am Donnerstag, den 24.06.2010, 12:36 +0200 schrieb Hans de Goede:
> Hi,
> 
> On 06/23/2010 03:29 PM, Alexey Fisher wrote:
> > Hallo all,
> > is there any way to force snd-usb-audio to use some "Vendor Specific
> > Class" device?
> > i currently got two webcams from my friends to take a look on. They are
> > cheep gspca based webcams with Mic. I wont to test if snd-usb-audio can
> > use it if i force it. Devices it self do not provide any hints for the
> > driver.
> >
> > lsusb -vd 093a:2468 | grep -i class
> >    bDeviceClass          255 Vendor Specific Class
> >    bDeviceSubClass       255 Vendor Specific Subclass
> >        bInterfaceClass       255 Vendor Specific Class
> >        bInterfaceSubClass    255 Vendor Specific Subclass
> >        bInterfaceClass       255 Vendor Specific Class
> >        bInterfaceSubClass    255 Vendor Specific Subclass
> >        bInterfaceClass       255 Vendor Specific Class
> >        bInterfaceSubClass    255 Vendor Specific Subclass
> >        bInterfaceClass       255 Vendor Specific Class
> >        bInterfaceSubClass    255 Vendor Specific Subclass
> >        bInterfaceClass       255 Vendor Specific Class
> >        bInterfaceSubClass    255 Vendor Specific Subclass
> >        bInterfaceClass       255 Vendor Specific Class
> >        bInterfaceSubClass    255 Vendor Specific Subclass
> >        bInterfaceClass       255 Vendor Specific Class
> >        bInterfaceSubClass    255 Vendor Specific Subclass
> >        bInterfaceClass       255 Vendor Specific Class
> >        bInterfaceSubClass    255 Vendor Specific Subclass
> >        bInterfaceClass       255 Vendor Specific Class
> >        bInterfaceSubClass    255 Vendor Specific Subclass
> >
> > regards,
> > Alexey
> >
> 
> 
> Don't bother, AFAIK these devices which are pixart pac207bca
> based do not contain any microphone at all. If they do they usually
> have 2 plugs at the end of their cable a usb plug and an analog
> one for the mic.
> 
> Google for pac207bca datasheet to find a useless datasheet, note
> that it does contain a listing of the physical pins of the device,
> and notice the lack of any pins to connect a microphone too.
> 
> If the pac207 supports a microphone (which I strongly believe
> it does not) the mic on these cameras is not a usb audio class
> compatible device. The pac207 declares only one interface so
> audio data ihas to be handled over the same interface
> as the video data. So in order to support the MIC you first need to
> find out how it works and then glew an alsa driver onto the
> gspca pac207 driver (as only one driver can be bound to a single
> usb interface).
> 
> Regards,
> 
> Hans, the pac207 driver maintainer
> 
> 
> p.s.
> 
> It would have been helpful if you had contacted me about this, I just
> happen to be subscribed to the alsa-devel list too.

Thank you for your response,
i buried this cam yesterday.
after some hours of useless hacking i went to "Trust" web page and
checked documentation. After i didn't found anything about sound i
extracted the driver and didn't found anything about sound ether. Then i
took windows and tested this cam... and ... no sound.
Memo on me: check documentation before wast time :/

Regards,
Alexey Fisher