[pulseaudio-discuss] Changes to deal with modem PCMs

[Mark Brown]

On Fri, Jul 27, 2012 at 01:38:30PM -0500, Pierre-Louis Bossart wrote:
> On 7/25/2012 4:19 PM, Mark Brown wrote:
> >If this is for fake streams held open by userspace we have a better in
> >kernel solution now - just hide the PCM from userspace entirely and
> >start it like anything else in the device.  Will that not suffice?

> I don't get it, I must have missed something. What do you mean by
> 'start it like anything else in the device'? Somehow userspace needs
> to enable the connection to the modem in phone use cases, if it's
> not done with a fake PCM then what is the assumption? Use a control
> interface?

PCM stream should just start like any other DAPM route between devices -
when there's an active input and an active output then the path gets
powered.  This may mean some controls if there's conditional routing in
the patch or if we're using PIN_SWITCH() to manage the power for the
input and output nodes but it doesn't have to.