[alsa-devel] [PATCH v3 14/15] ASoC: hdac_hdmi: Add jack reporting for user space

[Subhransu S. Prusty]

On Wed, Dec 09, 2015 at 09:13:56AM +0100, Takashi Iwai wrote:
> On Wed, 09 Dec 2015 09:03:38 +0100,
> Subhransu S. Prusty wrote:
> > 
> > Hi Takashi,
> > 
> > > > 
> > > > > > > Though, the max number of converters is limited, thus what you can
> > > > > > > actually use is defined by this constraint.  Due to this, we'll likely
> > > > > > > manage MST for the legacy HDA by assigning MST devs dynamically to
> > > > > > > pins in a certain procedure to make things compatible.
> > > > > > 
> > > > > > but how many MST devs are you going to create?
> > > > > 
> > > > > This is exactly the point: for the legacy HDA, instead of creating the
> > > > > entry for each MST devices, they are assigned dynamically to PCM at
> > > > > activation.  So the number of devices exposed to user-space is
> > > > > limited -- or better to say, user-space won't notice the difference.
> > > > 
> > > > And how many PCMs are you proposing for MST?
> > > 
> > > 5 for Intel, i.e. Nconv * 2 - 1.  This could be even Nconv, but we
> > > provide the reserved slots just for the compatible behavior that
> > > assumes the static pin/slot assignment.
> > >
> > 
> > How is Nconv * 2 - 1 PCMs are derived? Lets assume, there are 3 cvts and 4pins,
> > I think it will not work.
> 
> We're talking about Intel case, right?  Then both numbers are same.

Yes that's true. But was wondering what if it changes in future.

Regards,
Subhransu
> 
> 
> Takashi

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