[linux-sunxi] Re: [PATCH v2 04/27] dt-bindings: display: sunxi-drm: Add TCON TOP description

Jernej Škrabec
2018-06-13T16:03:21Z

Hi,

Dne sreda, 13. junij 2018 ob 09:34:56 CEST je Maxime Ripard napisal(a):
> Hi,
>
> Thanks for working on this!
>
> On Tue, Jun 12, 2018 at 10:00:13PM +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, selects TV encoder
> > clock source and contains additional TV TCON and DSI gates.
> >
> > Signed-off-by: Jernej Skrabec <jernej.skrabec@siol.net>
> > ---
> >
> > .../bindings/display/sunxi/sun4i-drm.txt | 45 +++++++++++++++++++
> > include/dt-bindings/clock/sun8i-tcon-top.h | 11 +++++
> > 2 files changed, 56 insertions(+)
> > create mode 100644 include/dt-bindings/clock/sun8i-tcon-top.h
> >
> > diff --git a/Documentation/devicetree/bindings/display/sunxi/sun4i-drm.txt
> > b/Documentation/devicetree/bindings/display/sunxi/sun4i-drm.txt index
> > 3346c1e2a7a0..ef64c589a4b3 100644
> > --- a/Documentation/devicetree/bindings/display/sunxi/sun4i-drm.txt
> > +++ b/Documentation/devicetree/bindings/display/sunxi/sun4i-drm.txt
> >
> > @@ -187,6 +187,51 @@ 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.
> > +
> > +It allows display pipeline to be configured in very different ways:
> > +
> > + / LCD0/LVDS0
> > + / TCON-LCD0
> > + | \ MIPI DSI
> > + mixer0 |
> > + \ / TCON-LCD1 - LCD1/LVDS1
> > + TCON-TOP
> > + / \ TCON-TV0 - TVE0/RGB
> > + mixer1 | \
> > + | TCON-TOP - HDMI
> > + | /
> > + \ TCON-TV1 - TVE1/RGB
> > +
> > +Note that both TCON TOP references same physical unit.
> > +
> > +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
>
> s/DRC/TCON TOP/ ?

Yes, copy & paste issue

>
> > + * rst: TCON TOP reset line
>
> Remaining consistent with the clock name would be great

You mean "ahb"? I noticed that most other nodes with reset lines don't have a
name associated. Maybe I could just drop it and use first specified reset?

>
> > + - reset-names: reset name mentioned above
> > + - #clock-cells : must contain 1
>
> An example would be nice here

You mean node example? with ports? In the past, Rob was against examples
unless really necessary. Node from R40 DTSI can serve as an example.

>
> > +- ports: A ports node with endpoint definitions as defined in
> > + Documentation/devicetree/bindings/media/video-interfaces.txt. The
> > first port + should be the input for mixer0 mux. The second should be
> > the output for that + mux. Third port should be input for mixer1 mux.
> > Fourth port should be output + for mixer1 mux. Fifth port should be
> > input for HDMI mux. Sixth port should + be output for it. All output
> > endpoints should have reg property with the id + of the target TCON.
> > All ports should have only one enpoint connected to
> ^ endpoint
>
> I guess it would me more readable if you were to make it a bullet
> list, but this works for me otherwise.

Since I have to fix this patch anyway, I can refactor this text.

Best regards,
Jernej