On Wed, Feb 02, 2022 at 02:43:12PM +0100, Maxime Ripard wrote: > On Wed, Feb 02, 2022 at 03:21:05PM +0200, Laurent Pinchart wrote: > > On Wed, Feb 02, 2022 at 02:16:23PM +0100, Maxime Ripard wrote: > > > On Wed, Feb 02, 2022 at 02:47:14PM +0200, Laurent Pinchart wrote: > > > > On Wed, Feb 02, 2022 at 10:48:45AM +0100, Maxime Ripard wrote: > > > > > On Thu, Jan 27, 2022 at 03:22:15PM +0100, Maxime Ripard wrote: > > > > > > On Tue, Jan 11, 2022 at 03:05:10PM +0200, Laurent Pinchart wrote: > > > > > > > On Tue, Jan 11, 2022 at 12:06:35PM +0100, Maxime Ripard wrote: > > > > > > > > Following the previous patch, let's introduce a generic panel-lvds > > > > > > > > binding that documents the panels that don't have any particular > > > > > > > > constraint documented. > > > > > > > > > > > > > > > > Reviewed-by: Rob Herring <robh@xxxxxxxxxx> > > > > > > > > Signed-off-by: Maxime Ripard <maxime@xxxxxxxxxx> > > > > > > > > > > > > > > > > --- > > > > > > > > > > > > > > > > Changes from v2: > > > > > > > > - Added a MAINTAINERS entry > > > > > > > > > > > > > > > > Changes from v1: > > > > > > > > - Added missing compatible > > > > > > > > - Fixed lint > > > > > > > > --- > > > > > > > > .../bindings/display/panel/panel-lvds.yaml | 57 +++++++++++++++++++ > > > > > > > > MAINTAINERS | 1 + > > > > > > > > 2 files changed, 58 insertions(+) > > > > > > > > create mode 100644 Documentation/devicetree/bindings/display/panel/panel-lvds.yaml > > > > > > > > > > > > > > > > diff --git a/Documentation/devicetree/bindings/display/panel/panel-lvds.yaml b/Documentation/devicetree/bindings/display/panel/panel-lvds.yaml > > > > > > > > new file mode 100644 > > > > > > > > index 000000000000..fcc50db6a812 > > > > > > > > --- /dev/null > > > > > > > > +++ b/Documentation/devicetree/bindings/display/panel/panel-lvds.yaml > > > > > > > > @@ -0,0 +1,57 @@ > > > > > > > > +# SPDX-License-Identifier: (GPL-2.0-only OR BSD-2-Clause) > > > > > > > > +%YAML 1.2 > > > > > > > > +--- > > > > > > > > +$id: http://devicetree.org/schemas/display/panel/panel-lvds.yaml# > > > > > > > > +$schema: http://devicetree.org/meta-schemas/core.yaml# > > > > > > > > + > > > > > > > > +title: Generic LVDS Display Panel Device Tree Bindings > > > > > > > > + > > > > > > > > +maintainers: > > > > > > > > + - Lad Prabhakar <prabhakar.mahadev-lad.rj@xxxxxxxxxxxxxx> > > > > > > > > + - Thierry Reding <thierry.reding@xxxxxxxxx> > > > > > > > > + > > > > > > > > +allOf: > > > > > > > > + - $ref: panel-common.yaml# > > > > > > > > + - $ref: /schemas/display/lvds.yaml/# > > > > > > > > + > > > > > > > > +select: > > > > > > > > + properties: > > > > > > > > + compatible: > > > > > > > > + contains: > > > > > > > > + const: panel-lvds > > > > > > > > + > > > > > > > > + not: > > > > > > > > + properties: > > > > > > > > + compatible: > > > > > > > > + contains: > > > > > > > > + enum: > > > > > > > > + - advantech,idk-1110wr > > > > > > > > + - advantech,idk-2121wr > > > > > > > > + - innolux,ee101ia-01d > > > > > > > > + - mitsubishi,aa104xd12 > > > > > > > > + - mitsubishi,aa121td01 > > > > > > > > + - sgd,gktw70sdae4se > > > > > > > > > > > > > > I still don't like this :-( Couldn't we instead do > > > > > > > > > > > > > > select: > > > > > > > properties: > > > > > > > compatible: > > > > > > > contains: > > > > > > > enum: > > > > > > > - auo,b101ew05 > > > > > > > - tbs,a711-panel > > > > > > > > > > > > > > ? > > > > > > > > > > > > That works too, I'll send another version. > > > > > > > > > > Actually, no, it doesn't work. > > > > > > > > > > If we do this, if we were to have a panel that has panel-lvds but none > > > > > of the other compatible (because of a typo, or downright invalid > > > > > binding) we won't validate it and report any error. > > > > > > > > > > I'll merge this version (together with the v4 version of patch 1) > > > > > > > > I'm sorry but I *really* *really* dislike this. Having to list all other > > > > compatible values in this file is a sign that something is wrong in the > > > > validation infrastructure. People will forget to update it when adding > > > > new bindings, and will get confused by the result. If I were a > > > > maintainer for DT bindings I'd nack this. > > > > > > The validation infrastructure is what it is, and we can't change that. > > > Rewriting one from scratch isn't reasonable either. That being said, the > > > *only* case where this has been a problem are the panels because there's > > > so many pointless schemas which should really be a single schema. > > > > > > That's the root cause. > > > > > > I tried to merge all of them, but once again panels seem to be special, > > > and it was shot down. So be it. But at the end of the day, there's not a > > > lot of solutions to do what we are doing for every other case out there. > > > > > > > If a DT has panel-lvds and no other compatible string, or invalid ones, > > > > won't the validation report that the compatible isn't understood ? I > > > > think that would be enough. > > > > > > That's just worse. How would you not get confused if there's an error > > > that the compatible isn't documented, you search for it, and it's > > > actually documented there? > > > > Is that any different than a binding that would have > > > > properties: > > compatible: > > items: > > enum: > > - foo,bar > > - foo,baz > > const: foo,base > > > > and a device tree that would set compatible = "foo,base"; ? This type of > > binding is very common, and I haven't heard anyone complaining that the > > resulting validation error is an issue. > > That works indeed, but it's not what panel-lvds is doing. For some > reason, instead of that enum, we need multiple schemas, one for each > combination. And this is why we need that select clause, to work around > that decision. I get that, but unless I'm mistaken, you concern with select: properties: compatible: contains: enum: - auo,b101ew05 - tbs,a711-panel is that it will result in skipping validation silently (until all nodes are required to be validated) if a DT contains compatible = "aou,b101ew05", "panel-lvds". Don't we also get the same problem with compatible = "foo,bat", "foo,base" ? How do the two issues differ ? -- Regards, Laurent Pinchart
