Re: [PATCH v4 1/7] dt-bindings: Add panel-timing subnode to simple-panel

From: Doug Anderson
Date: Thu Mar 28 2019 - 19:57:28 EST


Hi,


On Thu, Mar 28, 2019 at 1:27 PM Ezequiel Garcia <ezequiel@xxxxxxxxxxxxx> wrote:
>
> On Thu, 2019-03-28 at 10:17 -0700, Douglas Anderson wrote:
> > From: Sean Paul <seanpaul@xxxxxxxxxxxx>
> >
> > This patch adds a new subnode to simple-panel allowing us to override
> > the typical timing expressed in the panel's display_timing.
> >
> > Changes in v2:
> > - Split out the binding into a new patch (Rob)
> > - display-timings is a new section (Rob)
> > - Use the full display-timings subnode instead of picking the timing
> > out (Rob/Thierry)
> > Changes in v3:
> > - Go back to using the timing subnode directly, but rename to
> > panel-timing (Rob)
> > Changes in v4:
> > - Simplify desc. for when override should be used (Thierry/Laurent)
> > - Removed Rob H review since it's been a year and wording changed
> >
> > Cc: Doug Anderson <dianders@xxxxxxxxxxxx>
> > Cc: Eric Anholt <eric@xxxxxxxxxx>
> > Cc: Heiko Stuebner <heiko@xxxxxxxxx>
> > Cc: Jeffy Chen <jeffy.chen@xxxxxxxxxxxxxx>
> > Cc: Rob Herring <robh+dt@xxxxxxxxxx>
> > Cc: StÃphane Marchesin <marcheu@xxxxxxxxxxxx>
> > Cc: Thierry Reding <thierry.reding@xxxxxxxxx>
> > Cc: devicetree@xxxxxxxxxxxxxxx
> > Cc: dri-devel@xxxxxxxxxxxxxxxxxxxxx
> > Cc: linux-rockchip@xxxxxxxxxxxxxxxxxxx
> > Signed-off-by: Sean Paul <seanpaul@xxxxxxxxxxxx>
> > Signed-off-by: Douglas Anderson <dianders@xxxxxxxxxxxx>
> > ---
> >
> > .../bindings/display/panel/simple-panel.txt | 24 +++++++++++++++++++
> > 1 file changed, 24 insertions(+)
> >
> > diff --git a/Documentation/devicetree/bindings/display/panel/simple-panel.txt b/Documentation/devicetree/bindings/display/panel/simple-panel.txt
> > index b2b872c710f2..6157f86ddce4 100644
> > --- a/Documentation/devicetree/bindings/display/panel/simple-panel.txt
> > +++ b/Documentation/devicetree/bindings/display/panel/simple-panel.txt
> > @@ -15,6 +15,18 @@ Optional properties:
> > (hot plug detect) signal, but the signal isn't hooked up so we should
> > hardcode the max delay from the panel spec when powering up the panel.
> >
> > +panel-timing subnode
> > +--------------------
> > +
> > +This optional subnode is for devices which require a mode differing
> > +from the panel's "typical" display timing. The panel timings provided
> > +here will be ignored if they are found to be outside of allowable
> > +ranges for the given panel.
> > +
>
> Is it OK to put this comment about how the implementation
> will behave when values are out of range, given this is just a binding
> spec?
>
> Perhaps -if needed- this sentence can be rephrased to state that,
> e.g. the OS may not be able to apply these values, if the controller
> or device is unable to?

I will defer to Rob H. on this one, but I'm happy to simply remove the
last sentence. I was trying to add a more OS-agnostic version of the
bullet points from V3 but agree that we could just remove this from
the bindings completely.


-Doug