Re: [PATCH 04/15] dt-bindings: display: sunxi-drm: Add TCON TOP description

From: Jernej Åkrabec
Date: Mon May 21 2018 - 10:16:24 EST


Hi,

Dne ponedeljek, 21. maj 2018 ob 10:01:47 CEST je Maxime Ripard napisal(a):
> Hi,
>
> On Sat, May 19, 2018 at 08:31:16PM +0200, Jernej Skrabec wrote:
> > TCON TOP main purpose is to configure whole display pipeline. It
> > determines relationships between mixers and TCONs, selects source TCON
> > for HDMI, muxes LCD and TV encoder GPIO output,
>
> I'm not sure you mean GPIO here, but rather pin?

Right, I'll fix that.

>
> > selects TV encoder clock source and contains additional TV TCON and
> > DSI gates.
> >
> > Signed-off-by: Jernej Skrabec <jernej.skrabec@xxxxxxxx>
> > ---
> >
> > .../bindings/display/sunxi/sun4i-drm.txt | 20 +++++++++++++++++++
> > 1 file changed, 20 insertions(+)
> >
> > diff --git a/Documentation/devicetree/bindings/display/sunxi/sun4i-drm.txt
> > b/Documentation/devicetree/bindings/display/sunxi/sun4i-drm.txt index
> > 3346c1e2a7a0..a099957ab62a 100644
> > --- a/Documentation/devicetree/bindings/display/sunxi/sun4i-drm.txt
> > +++ b/Documentation/devicetree/bindings/display/sunxi/sun4i-drm.txt
> >
> > @@ -187,6 +187,26 @@ And on the A23, A31, A31s and A33, you need one more
clock line:
> > - 'lvds-alt': An alternative clock source, separate from the TCON
> > channel 0
> >
> > clock, that can be used to drive the LVDS clock
> >
> > +TCON TOP
> > +--------
> > +
> > +TCON TOPs main purpose is to configure whole display pipeline. It
> > determines +relationships between mixers and TCONs, selects source TCON
> > for HDMI, muxes +LCD and TV encoder GPIO output, selects TV encoder clock
> > source and contains +additional TV TCON and DSI gates.
> > +
> > +Required properties:
> > + - compatible: value must be one of:
> > + * allwinner,sun8i-r40-tcon-top
> > + - reg: base address and size of the memory-mapped region.
> > + - clocks: phandle to the clocks feeding the TCON TOP
> > + * bus: TCON TOP interface clock
> > + - clock-names: clock name mentioned above
> > + - resets: phandle to the reset line driving the DRC
> > + * rst: TCON TOP reset line
> > + - reset-names: reset name mentioned above
> > + - #clock-cells : must contain 1
> > +
>
> I guess you should better describe the OF-graph endpoints, and the
> clocks output. Just using the binding additions here doesn't allow to
> get a clear idea of how the DT should look like.

With my idea of implementation, OF graph is the same as before, so I didn't
mention anything about it.

My idea of dependencies (you should view it in fixed width font):
TCON-TOP
^
|
mixer <-> TCON <-> HDMI

I'll explain my design decision as response to other mail.

Best regards,
Jernej