[alsa-devel] [RFC 0/4] ASoC: Add HDA HDMI codec driver

[Vinod Koul]

On Fri, Oct 09, 2015 at 04:28:10PM +0100, Russell King - ARM Linux wrote:
> > I think we should set capabilities based on the sink capabilities. And these
> > should be set after reading the ELD. We want to do that when stream is
> > opened and we query ELD and set the constarinats based on ELD.
> > I have not added that code but this was the idea and was planned to come
> > after this
> 
> Note that there's sound/core/pcm_drm_eld.c which should help you with
> that.  Please help to improve it if it doesn't meet your needs - it's
> a helper precisely to set the constraints based on ELD.
> 
> It tries to find the best fit of sample rate vs channels given a ELD
> array of SADs.

That looks great. Yes I will use this and enhance it wherever required. It
makese sense to keep adding there rather than in driver

> > So we have discussed this with Takashi and the general idea is that we add a
> > SW mechanism as well which will be based on i915 component framework to read
> > ELD reliably from display driver
> > 
> > I think as a general idea all the hdmi audio drivers should rely on component
> > interface generically to read ELD/ get notification (that was added
> > recently). Today on audio we have i915 component interface and IMHO this
> > should be made a generic audio-display component interface and used by all.
> > The callbacks are not really HDA based. But I don't really know on other
> > arch if that is doable or not...
> 
> Do you have a pointer to this work?
sound/hda/hdac_i915.c

-- 
~Vinod