Re: [PATCH v1 2/8] dt-bindings: display: bridge: renesas,dsi-csi2-tx: Add r8a779g0

From: Geert Uytterhoeven <geert@linux-m68k.org>
To: Tomi Valkeinen <tomi.valkeinen@ideasonboard.com>
Cc: Laurent Pinchart <laurent.pinchart@ideasonboard.com>,
	Kieran Bingham <kieran.bingham+renesas@ideasonboard.com>,
	Rob Herring <robh+dt@kernel.org>,
	Krzysztof Kozlowski <krzysztof.kozlowski+dt@linaro.org>,
	Magnus Damm <magnus.damm@gmail.com>,
	dri-devel@lists.freedesktop.org,
	linux-renesas-soc@vger.kernel.org, devicetree@vger.kernel.org,
	linux-kernel@vger.kernel.org,
	Andrzej Hajda <andrzej.hajda@intel.com>,
	Neil Armstrong <neil.armstrong@linaro.org>,
	Robert Foss <robert.foss@linaro.org>,
	Jonas Karlman <jonas@kwiboo.se>,
	Jernej Skrabec <jernej.skrabec@gmail.com>,
	Tomi Valkeinen <tomi.valkeinen+renesas@ideasonboard.com>
Subject: Re: [PATCH v1 2/8] dt-bindings: display: bridge: renesas,dsi-csi2-tx: Add r8a779g0
Date: Tue, 22 Nov 2022 09:55:10 +0100	[thread overview]
Message-ID: <CAMuHMdWsvcd3_CX_dESW3EO4FoSGcMWAAyKO_5g2ch-jezdzzQ@mail.gmail.com> (raw)
In-Reply-To: <f5df3cb8-d315-b06b-aa04-f0b4af64a1c2@ideasonboard.com>

Hi Tomi,

On Tue, Nov 22, 2022 at 9:20 AM Tomi Valkeinen
<tomi.valkeinen@ideasonboard.com> wrote:
> On 17/11/2022 17:14, Geert Uytterhoeven wrote:
> > On Thu, Nov 17, 2022 at 1:26 PM Tomi Valkeinen
> > <tomi.valkeinen@ideasonboard.com> wrote:
> >> From: Tomi Valkeinen <tomi.valkeinen+renesas@ideasonboard.com>
> >>
> >> Extend the Renesas DSI display bindings to support the r8a779g0 V4H.
> >>
> >> Signed-off-by: Tomi Valkeinen <tomi.valkeinen+renesas@ideasonboard.com>
> >> ---
> >>   .../bindings/display/bridge/renesas,dsi-csi2-tx.yaml           | 3 ++-
> >>   1 file changed, 2 insertions(+), 1 deletion(-)
> >>
> >> diff --git a/Documentation/devicetree/bindings/display/bridge/renesas,dsi-csi2-tx.yaml b/Documentation/devicetree/bindings/display/bridge/renesas,dsi-csi2-tx.yaml
> >> index afeeb967393d..bc3101f77e5a 100644
> >> --- a/Documentation/devicetree/bindings/display/bridge/renesas,dsi-csi2-tx.yaml
> >> +++ b/Documentation/devicetree/bindings/display/bridge/renesas,dsi-csi2-tx.yaml
> >> @@ -11,13 +11,14 @@ maintainers:
> >>
> >>   description: |
> >>     This binding describes the MIPI DSI/CSI-2 encoder embedded in the Renesas
> >> -  R-Car V3U SoC. The encoder can operate in either DSI or CSI-2 mode, with up
> >> +  R-Car V3U/V4H SoC. The encoder can operate in either DSI or CSI-2 mode, with up
> >
> > Perhaps "R-Car Gen4 SoCs", so we stay within 80 chars, and don't have
> > to update this when the next member of the family is around the block?
>
> Is V3U gen 4? Or do you mean "R-Car V3U and Gen 4 SoCs"?

Despite the name, R-Car V3U is the first member of the R-Car Gen4 family...
https://www.renesas.com/us/en/products/automotive-products/automotive-system-chips-socs/r-car-v3u-best-class-r-car-v3u-asil-d-system-chip-automated-driving

> > Is there anything that might be SoC-specific?
> > If not, perhaps the time is ripe for a family-specific compatible value?
>
> At least v3u and v4h DSIs are slightly different. Well, the DSI IP block
> itself looks the same, but the PLL and PHY are different.

I noticed, when I saw the dsi-csi2 driver changes.
So no family-specific compatible value is needed.

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