Re: [PATCH v2 0/2] Add waveshare 7inch touchscreen panel support

[neil.armstrong@xxxxxxxxxx]

On 16/01/2024 10:32, Shengyang Chen wrote:
> Hi, Neil
>
> Thanks for your comment.
>
> > -----Original Message-----
> > From: neil.armstrong@xxxxxxxxxx <neil.armstrong@xxxxxxxxxx>
> > Sent: 2024年1月9日 19:19
> > To: Shengyang Chen <shengyang.chen@xxxxxxxxxxxxxxxx>;
> > devicetree@xxxxxxxxxxxxxxx; dri-devel@xxxxxxxxxxxxxxxxxxxxx
> > Cc: quic_jesszhan@xxxxxxxxxxx; sam@xxxxxxxxxxxx; airlied@xxxxxxxxx;
> > daniel@xxxxxxxx; maarten.lankhorst@xxxxxxxxxxxxxxx; mripard@xxxxxxxxxx;
> > tzimmermann@xxxxxxx; robh+dt@xxxxxxxxxx;
> > krzysztof.kozlowski+dt@xxxxxxxxxx; conor+dt@xxxxxxxxxx; wahrenst@xxxxxxx;
> > dave.stevenson@xxxxxxxxxxxxxxx; thierry.reding@xxxxxxxxx; Changhuang
> > Liang <changhuang.liang@xxxxxxxxxxxxxxxx>; Keith Zhao
> > <keith.zhao@xxxxxxxxxxxxxxxx>; Jack Zhu <jack.zhu@xxxxxxxxxxxxxxxx>;
> > linux-kernel@xxxxxxxxxxxxxxx
> > Subject: Re: [PATCH v2 0/2] Add waveshare 7inch touchscreen panel support
> >
> > Hi,
> >
> > On 09/01/2024 08:09, Shengyang Chen wrote:
> > > This patchset adds waveshare 7inch touchscreen panel support for the
> > > StarFive JH7110 SoC.
> >
> > Could you precise which SKU you're referring to ? is it 19885 =>
> > https://www.waveshare.com/7inch-dsi-lcd.htm ?
>
> yes, it is
> sorry for confusing you.
>
> > Are you sure it requires different timings from the RPi one ? In the Waveshare
> > wiki it explicitly uses the rpi setup (vc4-kms-dsi-7inch) to drive it:
> > https://www.waveshare.com/wiki/7inch_DSI_LCD
>
> Referring to Keith's answer
> https://lists.freedesktop.org/archives/dri-devel/2023-December/434200.html
> the panel timing value is generated to fit phy's bitrate and prevent overflow and underflow.
>
> Referring to the suggestion, we may try other timing from panel-simple to drive the panel.

Please implement a mode_fixup in your DSI host driver instead.

Neil

> > Neil
> >
> > > changes since v1:
> > > - Rebased on tag v6.7.
> > >
> > > patch 1:
> > > - Gave up original changing.
> > > - Changed the commit message.
> > > - Add compatible in panel-simple.yaml
> > >
> > > patch 2:
> > > - Gave up original changing.
> > > - Changed the commit message.
> > > - Add new mode for the panel in panel-simple.c
> > >
> > > v1:
> > > https://patchwork.kernel.org/project/dri-devel/cover/20231124104451.44
> > > 271-1-shengyang.chen@xxxxxxxxxxxxxxxx/
> > >
> > > Shengyang Chen (2):
> > >     dt-bindings: display: panel: panel-simple: Add compatible property for
> > >       waveshare 7inch touchscreen panel
> > >     gpu: drm: panel: panel-simple: add new display mode for waveshare
> > >       7inch touchscreen panel
> > >
> > >    .../bindings/display/panel/panel-simple.yaml  |  2 ++
> > >    drivers/gpu/drm/panel/panel-simple.c          | 28
> > +++++++++++++++++++
> > >    2 files changed, 30 insertions(+)
>
>
> Best Regards,
> Shengyang