Re: [PATCH v3 01/14] dt-bindings: display: renesas,cmm: Add R-Car CMM documentation

[Geert Uytterhoeven <geert@linux-m68k.org>]

Hi Laurent,

On Thu, Sep 5, 2019 at 1:50 PM Laurent Pinchart
<laurent.pinchart@ideasonboard.com> wrote:
> On Fri, Aug 30, 2019 at 08:01:09PM +0200, Jacopo Mondi wrote:
> > On Mon, Aug 26, 2019 at 01:15:50PM +0300, Laurent Pinchart wrote:
> > > How about converting this binding to yaml alreay ? It should be fairly
> > > simple.
> >
> > I'm trying to, and I'm having my portion of fun time at it.
> >
> > The definition of the schema itself seems good, but I wonder, is this
> > the first renesas schema we have? Because it seems to me the schema
> > validator is having an hard time to digest the examplea 'clocks' and
> > 'power-domains' properties, which have 1 phandle and 2 specifiers and 1
> > phandle and 1 specifier respectively for Rensas SoCs.
> >
> > In other words, if in the example I have:
> >
> >  examples:
> >    - |
> >      cmm0: cmm@fea40000 {
> >           compatible = "renesas,r8a7796-cmm";
> >           reg = <0 0xfea40000 0 0x1000>;
> >           clocks = <&cpg 711>              <---- 1 phandle + 1 specifier
> >           resets = <&cpg 711>;
> >           power-domains = <&sysc>;         <---- 1 phandle
> >      };
> >
> > The schema validation is good.
> >
> > While if I use an actual example
> >    - |
> >      cmm0: cmm@fea40000 {
> >           compatible = "renesas,r8a7796-cmm";
> >           reg = <0 0xfea40000 0 0x1000>;
> >           clocks = <&cpg CPG_MOD 711>         <---- 1 phandle + 2 specifier
> >           resets = <&cpg 711>;
> >           power-domains = <&sysc R8A7796_PD_ALWAYS_ON>; <---- 1 phandle
> >      };                                                       + 1 specfier
> >
> > The schema validation fails...
> > Error: Documentation/devicetree/bindings/display/renesas,cmm.example.dts:20.29-30 syntax error
> > FATAL ERROR: Unable to parse input tree
> >
> > Are clocks properties with > 2 entries and power-domains properties with
> > > 1 entries supported?
> >
> > Because from what I read here:
> > https://github.com/robherring/yaml-bindings/blob/master/schemas/clock/clock.yaml
> > "The length of a clock specifier is defined by the value of a #clock-cells
> > property in the clock provider node."
> >
> > And that's expected, but is the examples actually validated against the
> > clock provider pointed by the phandle? Because in that case, if we had a
> > yaml schema for the cpg-mssr provider, it would indeed specify clock-cells=2.
> >
> > Do we need a schema for cpg-mssr first, or am I doing something else
> > wrong?
>
> I think you just need to #include the headers that define CPG_MOD and
> R8A7796_PD_ALWAYS_ON.

If that helps, you might want to replace the symbols in the examples by their
actual values (1 resp. 32).

And perhaps keep the symbols as comments?

        clocks = <&cpg 1 /* CPG_MOD */ 711>;
        power-domains = <&sysc 32 /* R8A7796_PD_ALWAYS_ON */>;

Gr{oetje,eeting}s,

                        Geert

-- 
Geert Uytterhoeven -- There's lots of Linux beyond ia32 -- geert@linux-m68k.org

In personal conversations with technical people, I call myself a hacker. But
when I'm talking to journalists I just say "programmer" or something like that.
                                -- Linus Torvalds