Re: [PATCH v3 00/12] Add mipi dsi support for rk3288

Emil Velikov
2015-11-20T12:19:58Z

On 20 November 2015 at 07:02, Chris Zhong <zyw@rock-chips.com> wrote:
> Hi Emil
>
> On 11/19/2015 10:41 PM, Emil Velikov wrote:
>>
>> On 19 November 2015 at 03:35, Chris Zhong <zyw@rock-chips.com> wrote:
>>>
>>> The rk3288 MIPI DSI is a Synopsys DesignWare MIPI DSI host controller
>>> IP. This series adds support for a Synopsys DesignWare MIPI DSI host
>>> controller DRM bridge driver and a rockchip MIPI DSI specific DRM
>>> driver.
>>>
>>> This series also includes a DRM panel driver for BOE TV080WUM-NL0 panel.
>>> This panel only use the MIPI DSI video mode.
>>>
>>> The MIPI DSI feature is tested on rk3288 evb board, backport them to
>>> chrome os kernel v3.14, and it can display normally.
>>>
>>> This patchset is base on the patchset from Ying.liu@freescale.com.
>>> <http://www.spinics.net/lists/dri-devel/msg77181.html>
>>>
>>>
>>> Changes in v3:
>>> move the dw_mipi_dsi.txt to
>>> Documentation/devicetree/bindings/display/bridge
>>> move dw_mipi_dsi_rockchip.txt to bindings/display/rockchip/
>>> move boe,tv080wum-nl0.txt to bindings/display/panel/
>>>
>>> Changes in v2:
>>> add the mipi clk id in a single patch
>>> As Thierry.Reding comment, add a documentation for this panel.
>>>
>>> Chris Zhong (10):
>>> clk: rockchip: add id for mipidsi sclk on rk3288
>>> clk: rockchip: add mipidsi clocks on rk3288
>>> drm/rockchip: return a true clock rate to adjusted_mode
>>> drm/bridge: Add Synopsys DesignWare MIPI DSI host controller driver
>>
>> Did you actually rewrite the patch from Liu Ying ?
>
> I modify the dw_mipi_dsi.c based on the patch from Liu Ying.
If you base your work on top of (i.e. you rework) someone else's patch
you should retain this authorship and signed-off-by line. This of
course is not limited to the above patch but a general rule, afaik.

>>
>> Out of curiosity what was the obstacle of this work getting merged ?
>
> There are different version dw controller, and it is too hard to merge them,
> since most registers are different.
Have you discussed this limitation with Liu ? Does your work handle
both versions of the controller ? If so your commit message should say
something about that. Here are some good sources on the whats and whys
wrt writing good commit messages [1] [2]

[1] http://who-t.blogspot.co.uk/2009/12/on-commit-messages.html
[2] http://chris.beams.io/posts/git-commit/

>>
>>
>>> drm: rockchip: Support Synopsys DesignWare MIPI DSI host controller
>>> Documentation: dt-bindings: Add bindings for rk3288 DW MIPI DSI driver
>>> ARM: dts: rockchip: add rk3288 mipi_dsi nodes
>>> drm/panel: simple: Add support for BOE TV080WUM-NL0
>>> drm/panel: simple: Add boe,tv080wum-nl0 simple panel device tree
>>> binding
>>
>> As the DT people will tell you - there is no BOE vendor in
>> bindings/vendor-prefixes.txt.
>
> Yes, I have post a verdor patch in v2 series,
> <https://patchwork.kernel.org/patch/7530791/>
> Maybe I should add it back to series with
>
> Acked-by: Rob Herring<robh@kernel.org>
>
If a patch has been reviewed/acked that's great. Add the tag, but
please do not drop patches until they are merged. In the latter case
you can mention that your series depends on branch X from repo Y.

>>
>>> ARM: dts: rockchip: add support mipi panel tv080wum-nl0 for rk3288-evb
>>>
>>> Liu Ying (2):
>>> drm/dsi: Add a helper to get bits per pixel of MIPI DSI pixel format
>>> Documentation: dt-bindings: Add bindings for Synopsys DW MIPI DSI DRM
>>> bridge driver
>>>
>> >From the above 12 patches only ~6 reached this mailing list is that
>> intentional ? Previously I've seen people CC dri-devel for their
>> panel/bridge DT patches.
>
> I use the patman to post the series, forgot to add you and Thierry to the
> to-list.
> I will fix in next version series. Thanks for your reply.
>
No need to add me bth. Thierry on the other hand should be Cc'd on the
patches where he's the maintainer.

As the To/Cc list is already quite excessive - I'd suggest following
the approach used by veterans in kernel development.

I'm not a veteran kernel dev, but this is what I've noticed over the years:
- Subsystem foo - mailing-list, maintainer(s), and optionally the top
1-2 developers
- Other subsystems - mailing-list and optionally the maintainer(s).

Thus in the case of the panel driver you'll get - dri-devel, Thierry
and optionally(?) devicetree
For the DT binding for the panel driver - devicetree, Rob, dri-devel, Thierry.

...I think you get the idea :-)

Regards,
Emil