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Message-ID: <8600acf8-7b51-456b-8a81-4233cfd6f121@collabora.com>
Date: Tue, 9 Apr 2024 17:41:43 +0200
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Subject: Re: [PATCH v2 1/3] dt-bindings: display: mediatek: Add OF graph
 support for board path
To: Dmitry Baryshkov <dmitry.baryshkov@linaro.org>
Cc: chunkuang.hu@kernel.org, robh@kernel.org,
 krzysztof.kozlowski+dt@linaro.org, conor+dt@kernel.org,
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References: <20240409120211.321153-1-angelogioacchino.delregno@collabora.com>
 <20240409120211.321153-2-angelogioacchino.delregno@collabora.com>
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From: AngeloGioacchino Del Regno <angelogioacchino.delregno@collabora.com>
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Il 09/04/24 17:20, Dmitry Baryshkov ha scritto:
> On Tue, Apr 09, 2024 at 02:02:09PM +0200, AngeloGioacchino Del Regno wrote:
>> The display IPs in MediaTek SoCs support being interconnected with
>> different instances of DDP IPs (for example, merge0 or merge1) and/or
>> with different DDP IPs (for example, rdma can be connected with either
>> color, dpi, dsi, merge, etc), forming a full Display Data Path that
>> ends with an actual display.
>>
>> The final display pipeline is effectively board specific, as it does
>> depend on the display that is attached to it, and eventually on the
>> sensors supported by the board (for example, Adaptive Ambient Light
>> would need an Ambient Light Sensor, otherwise it's pointless!), other
>> than the output type.
> 
> With the color and gamma being in play, should the configuration be
> board-driver or rather use-case driven with the driver being able to
> reroute some of the blocks at runtime?
> 

The driver can already set some blocks to "BYPASS MODE" at runtime, meaning
that those will work as simple pass-through, performing *no* processing at
all, so that's addressed from the very beginning.

This doesn't mean that a specific pipeline must always support the "DISP_GAMMA"
or the "DISP_CCOLOR" block(s) alone, or together, or in combination with another
specific block.

For any other question, clarification, etc, I'm here :-)

Cheers!

>>
>> Add support for OF graphs to most of the MediaTek DDP (display) bindings
>> to add flexibility to build custom hardware paths, hence enabling board
>> specific configuration of the display pipeline and allowing to finally
>> migrate away from using hardcoded paths.
>>
>> Signed-off-by: AngeloGioacchino Del Regno <angelogioacchino.delregno@collabora.com>
>