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Message-ID: <ffad2e39-f775-00de-3119-f9b0ca3fe4f7@quicinc.com>
Date:   Fri, 8 Jul 2022 12:42:39 -0700
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Subject: Re: [PATCH] drm/msm/dsi: Set panel orientation when directly
 connected
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From:   Abhinav Kumar <quic_abhinavk@quicinc.com>
To:     Doug Anderson <dianders@chromium.org>,
        Stephen Boyd <swboyd@chromium.org>
CC:     Rob Clark <robdclark@gmail.com>,
        Dmitry Baryshkov <dmitry.baryshkov@linaro.org>,
        LKML <linux-kernel@vger.kernel.org>, <patches@lists.linux.dev>,
        Sean Paul <sean@poorly.run>,
        dri-devel <dri-devel@lists.freedesktop.org>,
        freedreno <freedreno@lists.freedesktop.org>,
        Hsin-Yi Wang <hsinyi@chromium.org>
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On 7/8/2022 9:00 AM, Abhinav Kumar wrote:
> 
> 
> On 7/8/2022 8:25 AM, Doug Anderson wrote:
>> Hi,
>>
>> On Wed, Jul 6, 2022 at 12:14 PM Stephen Boyd <swboyd@chromium.org> wrote:
>>>
>>> Set the panel orientation in drm when the panel is directly connected,
>>> i.e. we're not using an external bridge. The external bridge case is
>>> already handled by the panel bridge code, so we only update the path we
>>> take when the panel is directly connected/internal. This silences a
>>> warning splat coming from __drm_mode_object_add() on Wormdingler boards.
>>>
>>> Cc: Hsin-Yi Wang <hsinyi@chromium.org>
>>> Cc: Douglas Anderson <dianders@chromium.org>
>>> Signed-off-by: Stephen Boyd <swboyd@chromium.org>
>>> ---
>>>
>>> This relies on commit 5e41b01a7808 ("drm/panel: Add an API to allow drm
>>> to set orientation from panel") which is in drm-misc
>>>
>>>   drivers/gpu/drm/msm/dsi/dsi_manager.c | 2 ++
>>>   1 file changed, 2 insertions(+)
>>
>> I don't personally have objections to this, but (to my understanding)
>> "the future" is that everyone should use panel_bridge. If we made the
>> move to panel_bridge today then we wouldn't need to do this. In
>> general I think panel_bridge would end up letting us delete a bunch of
>> code...
>>
>> See commit 4e5763f03e10 ("drm/bridge: ti-sn65dsi86: Wrap panel with
>> panel-bridge") for when this was done by ti-sn65dsi86.
>>
>> Then again, I spent a small amount of time looking into this and it's
>> definitely non-trivial. Still likely worthwhile, but not worth
>> blocking a tiny fix like this. It also should be fairly obvious that
>> we should delete this when we switch to panel_bridge.
> 
> Right, from what I saw on IRC, panel_bridge is the way forward and 
> dmitry did push a change to do that
> 
> https://patchwork.freedesktop.org/patch/492585/
> 
> But I think we can go ahead with this change because its simple enough.
> 
> Regarding the panel_bridge migration, I am going to start reviewing that 
> as well.
> 

I did some more digging up on the panel_bridge migration.

Dmitry has posted this towards december last year

https://patches.linaro.org/project/dri-devel/patch/20211207222901.988484-3-dmitry.baryshkov@linaro.org/ 


and I had given my R-b on this already in Jan.

I am not sure why this change was dropped OR was not part of msm-next 
already.

Dmitry, any reason this change was left out so long and why the R-b was 
not retained and this was reposted?

 From what i can see the change looks identical.

Thanks

Abhinav
>>
>> Thus:
>>
>> Reviewed-by: Douglas Anderson <dianders@chromium.org>
>>
>> I'll assume that we'll just snooze this commit until drm-misc-next
>> merges into a tree that msm-next is based on, which will probably be
>> the next -rc1. If desired and Acked I could land this in
>> drm-misc-next, but it's probably not worth it?