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

[neil.armstr...@linaro.org]

On 16/01/2024 10:32, Shengyang Chen wrote:

Hi, Neil

Thanks for your comment.

-----Original Message-----
From: neil.armstr...@linaro.org <neil.armstr...@linaro.org>
Sent: 2024年1月9日 19:19
To: Shengyang Chen <shengyang.c...@starfivetech.com>;
devicet...@vger.kernel.org; dri-devel@lists.freedesktop.org
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Liang <changhuang.li...@starfivetech.com>; Keith Zhao
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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.c...@starfivetech.com/

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