Re: [PATCH RESEND v2 08/12] dt-bindings: add binding for generic eDP panel

Thierry Reding
2019-02-04T07:43:50Z

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On Sun, Feb 03, 2019 at 10:54:57AM -0800, Vasily Khoruzhick wrote:
> eDP panels usually have EDID EEPROM, so there's no need to define panel
> width/height or any modes/timings in dts. But this panel still may have
> regulator and/or backlight.
>
> Signed-off-by: Vasily Khoruzhick <anarsoul-Re5JQEeQqe8AvxtiuMwx3w@public.gmane.org>
> ---
> .../devicetree/bindings/display/panel/panel-edp.txt | 7 +++++++
> 1 file changed, 7 insertions(+)
> create mode 100644 Documentation/devicetree/bindings/display/panel/panel-edp.txt

Please don't try to make panels look more generic than they really are.
You're going to have to provide a compatible string for your device that
is more specific than "panel-edp". You claim that you don't need any
extra information that is panel specific, but you don't know that now.
We have in the past thought that we didn't need things like prepare
delay, but then we ran into situations where we did need them.

Just do what everybody else does. Provide a specific compatible string
and match on that in the panel-simple driver. Even if you can read all
the video timings from an EDID EEPROM, you can still provide a mode in
the panel descriptor to serve as a fallback if for example the EEPROM
is faulty on some device.

Thierry