Re: [PATCH v2] arm64: dts: renesas: r8a77961: Add lvds0 device node

From: Geert Uytterhoeven
Date: Fri Dec 24 2021 - 04:57:04 EST


Hi Nikita,

On Fri, Dec 24, 2021 at 6:00 AM Nikita Yushchenko
<nikita.yoush@xxxxxxxxxxxxxxxxxx> wrote:
> >> + lvds0: lvds@feb90000 {
> >> + compatible = "renesas,r8a7796-lvds";
> >
> > This should be "renesas,r8a77961-lvds".
> > To handle that, both the DT bindings[1] and the driver[2] should
> > be updated.
> >
> > [1] Documentation/devicetree/bindings/display/bridge/renesas,lvds.yaml
> > [2] drivers/gpu/drm/rcar-du/rcar_lvds.c
>
> Ok, will redo that way, although I don't really understand what for to have different compatible strings

Thank you!

> for exactly same IP inside different chips.

Ca. 30% of the "presumed identical" IP blocks in R-Car Gen3 SoCs
turned out not to be that identical...

> Also note that arch/arm64/boot/dts/renesas/r8a77951.dtsi currently has renesas,r8a7795-lvds

That was an early judgment error, which we regret making.
Initially, R-Car H3 ES2.0 (r8a77951) was assumed to be a slightly
improved variant of R-Car H3 ES1.x (r8a77950), while it turned out
to be a completely different SoC.

Gr{oetje,eeting}s,

Geert

--
Geert Uytterhoeven -- There's lots of Linux beyond ia32 -- geert@xxxxxxxxxxxxxx

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