Hi Rob,

On Tue, Nov 28, 2017 at 11:48:47AM -0600, Rob Herring wrote:
> Please CC DT list.
> 
> On Mon, Nov 27, 2017 at 9:41 AM, Maxime Ripard
> <maxime.ripard@free-electrons.com> wrote:
> > The power-supply property is used by a vast majority of panels, including
> > panel-simple. Let's document it as a common property
> >
> > Signed-off-by: Maxime Ripard <maxime.ripard@free-electrons.com>
> > ---
> >  Documentation/devicetree/bindings/display/panel/panel-common.txt | 6 ++++++
> >  Documentation/devicetree/bindings/display/panel/panel-lvds.txt   | 1 +
> >  2 files changed, 7 insertions(+)
> >
> > diff --git a/Documentation/devicetree/bindings/display/panel/panel-common.txt b/Documentation/devicetree/bindings/display/panel/panel-common.txt
> > index ec52c472c845..125ea68052af 100644
> > --- a/Documentation/devicetree/bindings/display/panel/panel-common.txt
> > +++ b/Documentation/devicetree/bindings/display/panel/panel-common.txt
> > @@ -78,6 +78,12 @@ used for panels that implement compatible control signals.
> >    while active. Active high reset signals can be supported by inverting the
> >    GPIO specifier polarity flag.
> >
> > +Power
> > +-----
> > +
> > +- power-supply: many display panels need an additional power supply in
> > +  order to be fully powered-up. For such panels, power-supply contains
> > +  a phandle to the regulator powering the panel.
> >
> >  Backlight
> >  ---------
> > diff --git a/Documentation/devicetree/bindings/display/panel/panel-lvds.txt b/Documentation/devicetree/bindings/display/panel/panel-lvds.txt
> > index b938269f841e..250850a2150b 100644
> > --- a/Documentation/devicetree/bindings/display/panel/panel-lvds.txt
> > +++ b/Documentation/devicetree/bindings/display/panel/panel-lvds.txt
> > @@ -32,6 +32,7 @@ Optional properties:
> >  - label: See panel-common.txt.
> >  - gpios: See panel-common.txt.
> >  - backlight: See panel-common.txt.
> > +- power-supply: See panel-common.txt.
> 
> simple-panel.txt should do the same.

I'll make simple-panel do that then

> Really, I'd like to see panel-common.txt and simple-panel.txt merged
> and simple-panel.txt removed altogether. But there are a lot of
> references back to simple-panel.txt. A given panel still needs to say
> what common properties it uses or doesn't use. Omitting a property
> like power-supply is ambiguous and can either mean "I only have 1
> supply" or "I haven't thought about supplies yet there are more than
> 1".

While I agree with you here, and in general, power-supply should be
mandatory, do you expect me to fix all the panel bindings as part of
this serie?

Maxime

-- 
Maxime Ripard, Free Electrons
Embedded Linux and Kernel engineering
http://free-electrons.com