[alsa-devel] Separate input and output jacks for one UCM device?

Liam Girdwood liam.r.girdwood at linux.intel.com
Thu Apr 2 08:39:10 CEST 2015


On Thu, 2015-04-02 at 07:24 +0800, Raymond Yau wrote:
> > > > >
> > > >
> > > > I've added a few others on the CC that would be interested.
> > > >
> > > > > My understanding is that a UCM device can represent a thing
> that has
> > > > > both input and output (I don't particularly like that, but
> it's too late
> > > > > to complain).
> > > >
> > > > Yes, but it can also represent simplex devices too e.g.
> > > > "Headset-Speakers" and "Headset-Mic". There are not any hard
> rules here,
> > > > but most examples are using duplex devices as historically UCM
> came from
> > > > the phone ecosystem use cases.
> 
> On some mobile phones which have FM radio , how do UCM handle FM radio
> since it need to use the headphone as antenna ?

This use case is just treated like any other where we have to set the
proper kcontrols and devices in the UCM config. This would include the
headphone if required for audio playback or antenna.

Liam



More information about the Alsa-devel mailing list