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Message-ID: <352e31de-cb79-f08e-b817-2712d97b84f1@linaro.org>
Date:   Thu, 3 Nov 2022 08:33:58 -0400
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Subject: Re: [PATCH 3/3] arm64: dts: exynos: Rename compatible string property
 from version to SOC specific
Content-Language: en-US
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
References: <20221102130602.48969-1-aakarsh.jain@samsung.com>
 <CGME20221102125816epcas5p23e16fefd6b820e7dd7d9a93f0d48f40d@epcas5p2.samsung.com>
 <20221102130602.48969-3-aakarsh.jain@samsung.com>
From:   Krzysztof Kozlowski <krzysztof.kozlowski@linaro.org>
In-Reply-To: <20221102130602.48969-3-aakarsh.jain@samsung.com>
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Precedence: bulk

On 02/11/2022 09:06, 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.
> 
> Suggested-by: Alim Akhtar <alim.akhtar@samsung.com>
> Fixes: 752d3a23d1f6 ("ARM: dts: add MFC codec device node for exynos3250")

There is no bug to fix and backporting is forbidden as it breaks the
usage of DTS in older kernel.

> 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";

The change is non-bisectable and breaks using DTS in older kernel.

Best regards,
Krzysztof