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Date:   Wed, 21 Jun 2023 10:14:34 +0200
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Subject: Re: [EXT] Re: [PATCH v6 2/8] dt-bindings: display: bridge: Add
 Cadence MHDP8501 HDMI and DP
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To:     Sandor Yu <sandor.yu@nxp.com>, Rob Herring <robh@kernel.org>
Cc:     "andrzej.hajda@intel.com" <andrzej.hajda@intel.com>,
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        "airlied@gmail.com" <airlied@gmail.com>,
        "daniel@ffwll.ch" <daniel@ffwll.ch>,
        "krzysztof.kozlowski+dt@linaro.org" 
        <krzysztof.kozlowski+dt@linaro.org>,
        "shawnguo@kernel.org" <shawnguo@kernel.org>,
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References: <cover.1686729444.git.Sandor.yu@nxp.com>
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From:   Krzysztof Kozlowski <krzysztof.kozlowski@linaro.org>
In-Reply-To: <PAXPR04MB94485F6E2DC5CDDBECED425FF45DA@PAXPR04MB9448.eurprd04.prod.outlook.com>
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On 21/06/2023 04:23, Sandor Yu wrote:
>>> +
>>> +properties:
>>> +  compatible:
>>> +    enum:
>>> +      - cdns,mhdp8501-dp
>>> +      - cdns,mhdp8501-hdmi
>>> +      - fsl,imx8mq-mhdp8501-dp
>>> +      - fsl,imx8mq-mhdp8501-hdmi
>>
>> Is DP vs. HDMI fixed for a particular SoC implementation or it's a board level
>> decision. In the latter case, the type of connector should determine the mode,
>> not compatible.
> DP or HDMI is bord level decision. 

Then it's a connector, not compatible.

> Because DP and HDMI have different initialize process and less functions could be reuse, so they have different drivers.

How do you organize drivers is independent of bindings.

> Please check it in patch
> [PATCH v6 3/8] drm: bridge: Cadence: Add MHDP8501 DP driver
> [PATCH v6 5/8] drm: bridge: Cadence: Add MHDP8501 HDMI driver
> 
> If use the type of connector to determine the mode, hdmi and DP driver have to combine into one driver.
> So the compatible may the better choice.

Why? Because one driver implementation tells you to do that? Bindings
are for hardware, not for driver, so whatever you have to do in drivers
is not convincing argument.

Best regards,
Krzysztof