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

[Jie, Yang]

> -----Original Message-----
> From: Takashi Iwai [mailto:tiwai at suse.de]
> Sent: Thursday, March 19, 2015 10:10 PM
> To: Liam Girdwood
> Cc: Tanu Kaskinen; alsa-devel at alsa-project.org; Arun Raghavan; Lu, Han;
> Mark Brown; Jie, Yang
> Subject: Re: Separate input and output jacks for one UCM device?
> 
> At Thu, 19 Mar 2015 09:15:59 +0000,
> Liam Girdwood wrote:
> >
> > On Wed, 2015-03-18 at 21:41 +0200, Tanu Kaskinen wrote:
> > > Hi Liam and alsa-devel,
> > >
> >
> > 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.
> >
> > > How likely do you think that there are or there will be some drivers
> > > that expose separate input and output jack kcontrols for a headset
> > > jack, to differentiate between headphones/headset/microphone? My
> > > understanding is that jack kcontrols store only booleans, so there's
> > > no way to distinguish between headphones and a headset with just one
> kcontrol.
> > >
> >
> > This sounds like we need to extend the jack kcontrol so that we can
> > differentiate between Headphones and Headset unless the kcontrol
> > naming was intended to differentiate and define the jack type ?
> 
> Yeah, that's what we really need to face seriously now to.
> Keyon is working on merging input and kctl jacks, and this is the biggest
> problem that has to be sorted out.
> 
> As far as I understand correctly, so far ASoC drivers also report headset as
> boolean (the bits are multiple, but reports are either zero or N bits).  So, we
> agreed on creating boolean "Headset" kctls.
> 
> One option is to provide multiple boolean kctls ("Headset Mic Jack").
[Keyon] how about using "Headset Jack Mic" and "Headset Jack Speakers"?
Then we can understand of that both these two kctls are belong to the
Headset Jack.
> Another option is to allow enum type for kctl jacks.  Or, yet another
> alternative is to provide an enum ctl (e.g. "Headset Jack Type") in addition to
> a boolean kctl ("Headset Jack").  There can be other ways, too...
> 
> 
> Takashi