Re: [Patch v3 3/3] ARM: dts: exynos: Rename compatible string property from version to SoC specific

[Krzysztof Kozlowski <krzk@kernel.org>]

On 11/11/2022 10:22, Aakarsh Jain wrote:
> Hi Krzysztof,
> 
>> -----Original Message-----
>> From: Krzysztof Kozlowski [mailto:krzysztof.kozlowski@linaro.org]
>> Sent: 11 November 2022 13:41
>> To: Aakarsh Jain <aakarsh.jain@samsung.com>; linux-arm-
>> kernel@lists.infradead.org; linux-media@vger.kernel.org; linux-
>> kernel@vger.kernel.org; devicetree@vger.kernel.org
>> Cc: m.szyprowski@samsung.com; andrzej.hajda@intel.com;
>> mchehab@kernel.org; hverkuil-cisco@xs4all.nl;
>> ezequiel@vanguardiasur.com.ar; jernej.skrabec@gmail.com;
>> benjamin.gaignard@collabora.com; krzysztof.kozlowski+dt@linaro.org;
>> stanimir.varbanov@linaro.org; dillon.minfei@gmail.com;
>> david.plowman@raspberrypi.com; mark.rutland@arm.com;
>> robh+dt@kernel.org; krzk+dt@kernel.org; andi@etezian.org;
>> alim.akhtar@samsung.com; aswani.reddy@samsung.com;
>> pankaj.dubey@samsung.com; smitha.t@samsung.com
>> Subject: Re: [Patch v3 3/3] ARM: dts: exynos: Rename compatible string
>> property from version to SoC specific
>>
>> On 11/11/2022 04:23, Aakarsh Jain wrote:
>>> commit "752d3a23d1f68de87e3c" which adds MFC codec device node for
>>> exynos3250 SoC. Since exynos3250.dtsi and exynos5420.dtsi are using
>>> same compatible string as "samsung,mfc-v7" but their node properties
>>> are different.As both SoCs have MFC v7 hardware module but with
>>> different clock hierarchy and complexity.
>>> So renaming compatible string from version specific to SoC based.
>>>
>>> Reviewed-by: Tommaso Merciai
>> <tommaso.merciai@amarulasolutions.com>
>>> Suggested-by: Alim Akhtar <alim.akhtar@samsung.com>
>>> Signed-off-by: Aakarsh Jain <aakarsh.jain@samsung.com>
>>> ---
>>>  arch/arm/boot/dts/exynos3250.dtsi | 2 +-
>>>  1 file changed, 1 insertion(+), 1 deletion(-)
>>>
>>> diff --git a/arch/arm/boot/dts/exynos3250.dtsi
>>> b/arch/arm/boot/dts/exynos3250.dtsi
>>> index 326b9e0ed8d3..98105c64f7d9 100644
>>> --- a/arch/arm/boot/dts/exynos3250.dtsi
>>> +++ b/arch/arm/boot/dts/exynos3250.dtsi
>>> @@ -485,7 +485,7 @@
>>>  		};
>>>
>>>  		mfc: codec@13400000 {
>>> -			compatible = "samsung,mfc-v7";
>>> +			compatible = "samsung,exynos3250-mfc";
>>
>> No improvements. Changeset is non-bisectable. I said it in v1, then in v2. So
>> now third time... Don't send a new version if you are not going to fix it or
>> resolve discussion.
>>
> My bad, misunderstood, now I understood your concerns around bisectability.
> 
> I hope you mean the below:
> ------
> diff --git a/Documentation/devicetree/bindings/media/s5p-mfc.txt b/Documentation/devicetree/bindings/media/s5p-mfc.txt
> index cb166654fa81..734e53445eb5 100644
> --- a/Documentation/devicetree/bindings/media/s5p-mfc.txt
> +++ b/Documentation/devicetree/bindings/media/s5p-mfc.txt
> @@ -10,7 +10,8 @@ Required properties:
>    - compatible : value should be either one among the following
>         (a) "samsung,mfc-v5" for MFC v5 present in Exynos4 SoCs
>         (b) "samsung,mfc-v6" for MFC v6 present in Exynos5 SoCs
> -       (c) "samsung,exynos3250-mfc" for MFC v7 present in Exynos3250 SoC
> +       (c) "samsung,exynos3250-mfc","samsung,mfc-v7" for MFC v7
> +            variant present in Exynos3250 SoC.
>         (d) "samsung,mfc-v7" for MFC v7 present in Exynos5420 SoC
>         (e) "samsung,mfc-v8" for MFC v8 present in Exynos5800 SoC
>         (f) "samsung,exynos5433-mfc" for MFC v8 present in Exynos5433 SoC
> diff --git a/arch/arm/boot/dts/exynos3250.dtsi b/arch/arm/boot/dts/exynos3250.dtsi
> index 98105c64f7d9..a2d6ee7fff08 100644
> --- a/arch/arm/boot/dts/exynos3250.dtsi
> +++ b/arch/arm/boot/dts/exynos3250.dtsi
> @@ -485,7 +485,7 @@
>                 };
> 
>                 mfc: codec@13400000 {
> -                       compatible = "samsung,exynos3250-mfc";
> +                       compatible = "samsung,exynos3250-mfc", "samsung,mfc-v7";
>                         reg = <0x13400000 0x10000>;
>                         interrupts = <GIC_SPI 102 IRQ_TYPE_LEVEL_HIGH>;
>                         clock-names = "mfc", "sclk_mfc";
> -----
> 
> Where mfc-v7 will be used as fallback for the older kernel which might use new dtb.
> 
> Let me know if this is not what you meant or am I still missing something?

Yes, this is what I meant. Thanks.

Best regards,
Krzysztof