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From:   Linus Walleij <linus.walleij@linaro.org>
Date:   Fri, 16 Jun 2023 14:52:52 +0200
Message-ID: <CACRpkdYXtQwmZR1u-1fwmyC_8Yq4bMkjDBcUCfuGqSz_UhXWJQ@mail.gmail.com>
Subject: Re: [PATCH v4 3/3] drm/panel-fannal-c3004: Add fannal c3004 DSI panel
To:     Paulo Pavacic <pavacic.p@gmail.com>
Cc:     neil.armstrong@linaro.org, sam@ravnborg.org, airlied@gmail.com,
        daniel@ffwll.ch, robh+dt@kernel.org,
        krzysztof.kozlowski+dt@linaro.org, conor+dt@kernel.org,
        devicetree@vger.kernel.org, linux-kernel@vger.kernel.org,
        dri-devel@lists.freedesktop.org
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On Fri, Jun 16, 2023 at 2:31=E2=80=AFPM Paulo Pavacic <pavacic.p@gmail.com>=
 wrote:
> pet, 16. lip 2023. u 13:44 Linus Walleij <linus.walleij@linaro.org> napis=
ao je:
> >
> > On Fri, Jun 16, 2023 at 11:57=E2=80=AFAM Paulo Pavacic <pavacic.p@gmail=
.com> wrote:
> > > =C4=8Det, 15. lip 2023. u 21:55 Linus Walleij <linus.walleij@linaro.o=
rg> napisao je:
> > > >
> > > > I doubt that the display controller is actually by Fannal, but I gu=
ess
> > > > you tried to find out? We usually try to identify the underlying di=
splay
> > > > controller so the driver can be named after it and reused for more
> > > > display panels.
> > >
> > > Yes, of course, the controller is ST7701S.
> >
> > Hm did you try to just refactor
> > drivers/gpu/drm/panel/panel-sitronix-st7701.c
> > to support your new panel?
>
> Yes I have tried, but there are too many changes needed and I wasn't
> sure whether I would be breaking compatibility with st7701 based
> panels.

For the community it creates a problem that now two drivers for similar
hardware need to be maintained, and that burden will land on the DRM
maintainers. For this reason it would be better if a joint driver could
be created.

I am sure the users of the old driver will be willing to test patches to
make sure their devices keep working.

Yours,
Linus Walleij