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

[Shengyang Chen]

Hi, Stefan

Thanks for your comment and suggestion.

> -----Original Message-----
> From: Stefan Wahren <wahrenst@xxxxxxx>
> Sent: 2024年1月10日 1:22
> To: neil.armstrong@xxxxxxxxxx; Shengyang Chen
> <shengyang.chen@xxxxxxxxxxxxxxxx>; devicetree@xxxxxxxxxxxxxxx;
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> dave.stevenson@xxxxxxxxxxxxxxx; thierry.reding@xxxxxxxxx; Changhuang
> Liang <changhuang.liang@xxxxxxxxxxxxxxxx>; Keith Zhao
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> linux-kernel@xxxxxxxxxxxxxxx
> Subject: Re: [PATCH v2 0/2] Add waveshare 7inch touchscreen panel support
> 
> Hi Neil,
> 
> Am 09.01.24 um 12:19 schrieb neil.armstrong@xxxxxxxxxx:
> > 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 ?
> >
> > 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
> i don't have an anser for your question, but the Raspberry Pi vendor tree use
> different timings than the Mainline kernel:
> 
> https://github.com/raspberrypi/linux/commit/222b9baa97cc4c880d040a8c6a5
> da80d6a42c8e8
> 
> Additionally the
> arm64/boot/dts/freescale/imx8mm-venice-gw72xx-0x-rpidsi.dtso suggests that
> it uses the Raspberry Pi 7inch, but uses the timings of
> powertip,ph800480t013-idf02 from panel-simple.
> 
> Maybe Shengyang could test these timings with the Waveshare touch. At the
> end this rely on a proper implementation on the underlying drivers.
> 
> Sorry, for adding more confusion.
> 
Thanks for suggestion.
We will try other timing from panel-simple.
Maybe we are not going to commit new panel timing patch
if we find useful timing from panel-simple to drive the panel.

> Regards
> >
> > 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/20231124104451.4
> >> 4271-1-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(+)
> >>
> >

thanks

Best Regards,
Shengyang