RE: [PATCH v6 03/13] dt-bindings: serial: Add compatible for Renesas RZ/T2H SoC in sci

[Thierry Bultel]

Hi Geert,

> -----Original Message-----
> From: Geert Uytterhoeven <geert@xxxxxxxxxxxxxx>
> Sent: lundi 31 mars 2025 15:04
> To: Thierry Bultel <thierry.bultel.yh@xxxxxxxxxxxxxx>
> Cc: thierry.bultel@xxxxxxxxxxx; linux-renesas-soc@xxxxxxxxxxxxxxx; Paul
> Barker <paul.barker.ct@xxxxxxxxxxxxxx>; Rob Herring <robh@xxxxxxxxxx>;
> Geert Uytterhoeven <geert+renesas@xxxxxxxxx>; linux-
> kernel@xxxxxxxxxxxxxxx; linux-serial@xxxxxxxxxxxxxxx;
> devicetree@xxxxxxxxxxxxxxx
> Subject: Re: [PATCH v6 03/13] dt-bindings: serial: Add compatible for
> Renesas RZ/T2H SoC in sci
> 
> Hi Thierry,
> 
> Thanks for the update!
> 
> On Mon, 31 Mar 2025 at 14:27, Thierry Bultel
> <thierry.bultel.yh@xxxxxxxxxxxxxx> wrote:
> > The SCI of RZ/T2H SoC (a.k.a r9a09g077), as a lot
> 
> RSCI in the RZ/T2H SoC ... has
> 
> > of similarities with other Renesas SoC like G2L, G3S, V2L;
> 
> ... with SCI in other ..
> 
> > However, it has a different set of registers, and in addition to
> > serial, this IP also supports SCIe (encoder), SmartCard, i2c and spi.
> > This is why the 'renesas,sci' fallback for generic SCI does not apply
> for it.
> >
> > Reviewed-by: Rob Herring (Arm) <robh@xxxxxxxxxx>
> > Signed-off-by: Thierry Bultel <thierry.bultel.yh@xxxxxxxxxxxxxx>
> 
> > --- a/Documentation/devicetree/bindings/serial/renesas,sci.yaml
> > +++ b/Documentation/devicetree/bindings/serial/renesas,sci.yaml
> 
> Given we're now using the "RSCI" naming, I think it deserves its own DT
> binding document.

All right, but I have then several questions
1) I am not sure it can have generic fallback,
e.g. something like :

properties:
  compatible:
    - const: renesas,r9a09g077-rsci      # RZ/T2H

... is just enough, can you confirm ?

2) Should I also change the node name in .dtsi file from 'sci0' to 'rsci0' ?

Thanks !

> 
> > @@ -9,9 +9,6 @@ title: Renesas Serial Communication Interface
> >  maintainers:
> >    - Geert Uytterhoeven <geert+renesas@xxxxxxxxx>
> >
> > -allOf:
> > -  - $ref: serial.yaml#
> > -
> >  properties:
> >    compatible:
> >      oneOf:
> > @@ -22,6 +19,8 @@ properties:
> >                - renesas,r9a07g054-sci     # RZ/V2L
> >            - const: renesas,sci            # generic SCI compatible UART
> >
> > +      - const: renesas,r9a09g077-sci      # RZ/T2H
> 
> renesas,r9a09g077-rsci
> 
> > +
> >        - items:
> >            - const: renesas,sci            # generic SCI compatible UART
> >
> 
> 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