[PATCH v7 4/8] drm/sunxi: Add DT bindings documentation of Allwinner HDMI

[Jean-Francois Moine]

On Tue, 29 Nov 2016 22:10:01 +0200
Laurent Pinchart <laurent.pinchart at ideasonboard.com> wrote:

> Hi Jean-François,
> 
> On Tuesday 29 Nov 2016 21:04:55 Jean-Francois Moine wrote:
> > On Tue, 29 Nov 2016 21:33 +0200 Laurent Pinchart wrote:
> > >>> You need a third port for the HDMI encoder output, connected to an
> > >>> HDMI connector DT node.
> > >> 
> > >> I don't see what you mean. The HDMI device is both the encoder
> > >> and connector (as the TDA998x):
> > >
> > > The driver might create both an encoder and a connector, but I very much
> > > doubt that the "allwinner,sun8i-a83t-hdmi" hardware contains a connector,
> > > unless the SoC package has an HDMI connector coming out of it :-)
> > > 
> > >> plane -> DE2 mixer ---> TCON -----> HDMI -----> display device
> > >> ----- plane ------    - CRTC -   - encoder  \
> > >>                                    connector -- (HDMI cable)
> > >>          audio-controller -   - audio-codec /
> > 
> > The schema is the same as the Dove Cubox: the TDA998x is just a chip
> > with some wires going out and the physical connector is supposed to be
> > at the end of the wires.
> 
> I've missed the Dove Cubox DT bindings when they were submitted. Fortunately 
> (or unfortunately for you, depending on how you look at it ;-)) I've paid more 
> attention this time.
> 
> > Here, the HDMI pins of the SoC go to a pure hardware chip and then to
> > the physical connector. Which software entity do you want to add?
> 
> I don't want to add a software entity, I just want to model the connector in 
> DT as it's present in the system. Even though that's more common for other bus 
> types than HDMI (LVDS for instance) it wouldn't be inconceivable to connect 
> the HDMI signals to an on-board chim instead of an HDMI connector, so the HDMI 
> encoder output should be modelled by a port and connected to a connector DT 
> node in this case.

Well, I don't see what this connector can be.
May you give me a DT example?

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