[PATCH v2 1/4] dt-bindings: display: panel: samsung,atna33xc20: Document ATNA45AF01

[Doug Anderson]

Hi,

On Thu, Jul 18, 2024 at 7:56 AM Conor Dooley <conor at kernel.org> wrote:
>
> On Thu, Jul 18, 2024 at 07:45:57AM -0700, Doug Anderson wrote:
> > Hi,
> >
> > On Wed, Jul 17, 2024 at 11:19 PM Krzysztof Kozlowski <krzk at kernel.org> wrote:
> > >
> > > On 18/07/2024 02:21, Doug Anderson wrote:
> > > > Conor (and/or) Krzysztof and Rob,
> > > >
> > > > On Mon, Jul 15, 2024 at 8:31 AM Conor Dooley <conor at kernel.org> wrote:
> > > >>
> > > >> On Mon, Jul 15, 2024 at 02:15:37PM +0200, Stephan Gerhold wrote:
> > > >>> The Samsung ATNA45AF01 panel is an AMOLED eDP panel that has backlight
> > > >>> control over the DP AUX channel. While it works almost correctly with the
> > > >>> generic "edp-panel" compatible, the backlight needs special handling to
> > > >>> work correctly. It is similar to the existing ATNA33XC20 panel, just with
> > > >>> a larger resolution and size.
> > > >>>
> > > >>> Add a new "samsung,atna45af01" compatible to describe this panel in the DT.
> > > >>> Use the existing "samsung,atna33xc20" as fallback compatible since existing
> > > >>> drivers should work as-is, given that resolution and size are discoverable
> > > >>> through the eDP link.
> > > >>>
> > > >>> Signed-off-by: Stephan Gerhold <stephan.gerhold at linaro.org>
> > > >>
> > > >> Acked-by: Conor Dooley <conor.dooley at microchip.com>
> > > >
> > > > Can you comment on whether you would consider this bindings a "Fix"
> > > > since it's a dependency for later patches in this series (which are
> > > > "Fix"es) to pass dtbs_check? See:
> > > >
> > > > https://lore.kernel.org/r/4bca316a-2334-425b-87a6-e1bb241d26b5@linaro.org
> > >
> > > The patch itself is not a fix, for sure, but it might be a dependency of
> > > a fix (which you wrote above), thus could be pulled to stable as a
> > > dependency.
> > >
> > > I do not care about dtbs_check warnings in stable kernels, mostly
> > > because dtbs_check warnings depend heavily on dtschema and dtschema
> > > follows mainline kernel. Basically if you had warnings-free v6.8 but try
> > > to run dtbs_check now with latest dtschema, your results will differ.
> > >
> > > At some point in the future, I could imagine "no new dtbs_check warnings
> > > in stable kernels" requirement or at least preference, but so far I
> > > don't think there is any benefit.
> >
> > In this case it's not about whether it makes it to the stable kernel
> > but about which main kernel it goes through.
> >
> > If we land the bindings in drm-misc-next right now then it'll be a
> > long time before it makes it into Linus's tree because of the way that
> > drm-misc-next merges. It will make it to Linus's tree at 6.12. You can
> > see the drm-misc merging strategy at:
> >
> > https://drm.pages.freedesktop.org/maintainer-tools/drm-misc.html
> >
> > If we land the dts change (a fix) through the Qualcomm tree as a fix
> > then it should target 6.11.
> >
> > This means that the 6.11 tree will have a dtbs_check error because it
> > has the dts change (a fix) but not the bindings change (not a fix).
> >
> > One way to resolve this would be to treat this bindings as a "fix" and
> > land it through "drm-misc-fixes". That would make the bindings and
> > device tree change meet up in Linux 6.11.
> >
> > Did I get that all correct?
>
> Is not not fairly established that a dependency for a fix can go onto a
> fixes branch even if it is not a fix in and of itself?

That would certainly be my take on it, but DT folks confirmation was
requested by Neil in:

https://lore.kernel.org/all/4bca316a-2334-425b-87a6-e1bb241d26b5@linaro.org/

-Doug