Re: Xen PV audio XenStore

[Konrad Rzeszutek Wilk <konrad.wilk@oracle.com>]

On Tue, Jul 05, 2011 at 01:02:08PM +0100, Ian Campbell wrote:
> On Mon, 2011-07-04 at 23:16 +0100, George Boutsioukis wrote:
> > Hello everyone, as some of you may remember there is a GSoC project
> > this year to implement a paravirtualized audio driver and I am the
> > student undertaking this effort.
> > 
> > As the rest of the PV audio drivers, my frontend uses XenStore to pass
> > the event channel & grant reference to the backend, along with a few
> > configuration data. Although the driver is far from usable, the
> > XenStore layout is not going to change much in the future, so I think
> > it would be useful to describe it to the community.
> > 
> > First of all, although the frontend is implemented in userspace, I
> > tried to follow the scheme used by the rest of the PV drivers. This
> > looks something like:
> > 
> > /local/domain/<domID>/device/audio/<devID>/event-channel
> > /local/domain/<domID>/device/audio/<devID>/ring-ref
> > /local/domain/<domID>/device/audio/<devID>/format
> > /local/domain/<domID>/device/audio/<devID>/rate
> > /local/domain/<domID>/device/audio/<devID>/channels

And "format" is...? string? What does it look like?
> > 
> > where devID is a unique device ID for the guest system.

Could you provide an example of what this layout looks like for
stereo microphone (each channel is 8bit-unsigned, 44Khz) and
5.1 channel output with 48Khz of ulaw-16bit signed?