Re: [PATCH v3 2/3] dt-bindings: serial: amlogic,meson-uart: Add compatible string for T7

[Neil Armstrong]

On 22/06/2023 09:36, Lucas Tanure wrote:
> On Thu, Jun 22, 2023 at 8:12 AM Conor Dooley <conor.dooley@xxxxxxxxxxxxx> wrote:
> > On Thu, Jun 22, 2023 at 07:43:31AM +0100, Lucas Tanure wrote:
> > > On Thu, Jun 22, 2023 at 7:05 AM Krzysztof Kozlowski
> > > <krzysztof.kozlowski@xxxxxxxxxx> wrote:
> > > > On 22/06/2023 07:32, Lucas Tanure wrote:
> > > > > On Wed, Jun 21, 2023 at 7:12 PM Conor Dooley <conor@xxxxxxxxxx> wrote:
> > > > > > On Wed, Jun 21, 2023 at 03:53:04PM +0200, Krzysztof Kozlowski wrote:
> > > > > > > On 21/06/2023 15:32, Lucas Tanure wrote:
> > > > > > > > Amlogic T7 SoCs uses the same UART controller as S4 SoCs and G12A.
> > > > > > > > There is no need for an extra compatible line in the driver, but
> > > > > > > > add T7 compatible line for documentation.
> > > > > > > >
> > > > > > > > Signed-off-by: Lucas Tanure <tanure@xxxxxxxxx>
> > > > > > > > ---
> > > > > > > >   .../devicetree/bindings/serial/amlogic,meson-uart.yaml          | 2 ++
> > > > > > > >   1 file changed, 2 insertions(+)
> > > > > > > >
> > > > > > > > diff --git a/Documentation/devicetree/bindings/serial/amlogic,meson-uart.yaml b/Documentation/devicetree/bindings/serial/amlogic,meson-uart.yaml
> > > > > > > > index 01ec45b3b406..860ab58d87b0 100644
> > > > > > > > --- a/Documentation/devicetree/bindings/serial/amlogic,meson-uart.yaml
> > > > > > > > +++ b/Documentation/devicetree/bindings/serial/amlogic,meson-uart.yaml
> > > > > > > > @@ -33,6 +33,7 @@ properties:
> > > > > > > >                 - amlogic,meson8b-uart
> > > > > > > >                 - amlogic,meson-gx-uart
> > > > > > > >                 - amlogic,meson-s4-uart
> > > > > > > > +              - amlogic,meson-t7-uart
> > > > > > > >             - const: amlogic,meson-ao-uart
> > > > > > > >         - description: Always-on power domain UART controller on G12A SoCs
> > > > > > > >           items:
> > > > > > > > @@ -46,6 +47,7 @@ properties:
> > > > > > > >             - amlogic,meson8b-uart
> > > > > > > >             - amlogic,meson-gx-uart
> > > > > > > >             - amlogic,meson-s4-uart
> > > > > > > > +          - amlogic,meson-t7-uart
> > > > > > >
> > > > > > > It does not look like you tested the DTS against bindings. Please run
> > > > > > > `make dtbs_check` (see
> > > > > > > Documentation/devicetree/bindings/writing-schema.rst or
> > > > > > > https://www.linaro.org/blog/tips-and-tricks-for-validating-devicetree-sources-with-the-devicetree-schema/
> > > > > > > for instructions).
> > > > > >
> > > > > > Check back on the previous version, I should've posted an untested
> > > > > > version of what you need to add.
> > > > > I saw that, but adding a S4 doesn't make sense to me. And you didn't
> > > > > show the entire change, so I can't understand what you want there.
> > > >
> > > > For sure you need something which does not trigger errors. If you claim
> > > > adding S4 as fallback does not make sense, then why did you use it?
> > > > Sending a code which is clearly incorrect does not make sense.
> > > Sorry, I think we are talking about different things. It does not make
> > > sense to me to add an S4 line in the documentation when it is already
> > > there. So I could not understand or make sense of the patch Conor sent
> > > in reply to my V2.
> >
> > That is just how it works. You need to spell out exactly which
> > combinations are permitted. The current entry for s4 says that s4 is
> > only permitted in isolation.
> > Since you are adding "amlogic,meson-t7-uart", "amlogic,meson-s4-uart"
> > you need to explicitly allow that combination. You'll notice if you look
> > at the file that the gx uart appears more than once.
> >
> > Given the g12a was the most recently added compatible, it might make
> > sense to follow the pattern that it had set, given the thing your
> > original patch copied the match data from was the g12a. That change to
> > the dt-binding would look like:
> > diff --git a/Documentation/devicetree/bindings/serial/amlogic,meson-uart.yaml b/Documentation/devicetree/bindings/serial/amlogic,meson-uart.yaml
> > index 01ec45b3b406..eae11e87b88a 100644
> > --- a/Documentation/devicetree/bindings/serial/amlogic,meson-uart.yaml
> > +++ b/Documentation/devicetree/bindings/serial/amlogic,meson-uart.yaml
> > @@ -50,6 +50,13 @@ properties:
> >           items:
> >             - const: amlogic,meson-g12a-uart
> >             - const: amlogic,meson-gx-uart
> > +      - description:
> > +          Everything-Else power domain UART controller on G12A compatible SoCs
> > +        items:
> > +          - enum:
> > +              - amlogic,meson-t7-uart
> > +          - const: amlogic,meson-g12a-uart
> > +          - const: amlogic,meson-gx-uart
> >
> >     reg:
> >       maxItems: 1
> >
> > /I/ don't really care whether you do that, or do the s4 version of it,
> > but following the most recent pattern might make more sense. When I
> > suggested s4, it was because I only looked at the driver patch rather
> > than the code itself.
> >
> > > Krzysztof, I will check again with dtbs_check and re-send.
> >
> > Cheers,
> > Conor.
> I am struggling to understand this. Everything I try fails the check.

I just applied Conor's change on top of v6.4-rc1 and ran:
make dt_binding_check DT_SCHEMA_FILES=Documentation/devicetree/bindings/serial/amlogic,meson-uart.yaml

and the check was successful.

Neil