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Message-ID: <76a7f819-f3d2-d39d-1bc9-f1e7f837fd22@linaro.org>
Date:   Wed, 21 Jun 2023 08:02:46 +0200
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Subject: Re: [PATCH v2 2/2] arm64: dts: meson-t7-a311d2-khadas-vim4: add
 initial device-tree
To:     Yixun Lan <dlan@gentoo.org>, Lucas Tanure <tanure@linux.com>
Cc:     Rob Herring <robh+dt@kernel.org>,
        Krzysztof Kozlowski <krzysztof.kozlowski+dt@linaro.org>,
        Conor Dooley <conor+dt@kernel.org>,
        Neil Armstrong <neil.armstrong@linaro.org>,
        Jerome Brunet <jbrunet@baylibre.com>,
        Kevin Hilman <khilman@baylibre.com>, Nick <nick@khadas.com>,
        Artem <art@khadas.com>, devicetree@vger.kernel.org,
        linux-kernel@vger.kernel.org, linux-amlogic@lists.infradead.org,
        linux-arm-kernel@lists.infradead.org
References: <20230620134857.238941-1-tanure@linux.com>
 <20230620134857.238941-3-tanure@linux.com> <ZJIjtphyKdC48JrN@ofant>
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From:   Krzysztof Kozlowski <krzysztof.kozlowski@linaro.org>
In-Reply-To: <ZJIjtphyKdC48JrN@ofant>
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On 21/06/2023 00:09, Yixun Lan wrote:
>> +		apb4: bus@fe000000 {
>> +			compatible = "simple-bus";
>> +			reg = <0x0 0xfe000000 0x0 0x480000>;
>> +			#address-cells = <2>;
>> +			#size-cells = <2>;
>> +			ranges = <0x0 0x0 0x0 0xfe000000 0x0 0x480000>;
>> +
>> +			uart_A: serial@78000 {
>> +				compatible = "amlogic,meson-t7-uart",
>                                               ~~~~~~~~~~~~~~~~~
> if you introduce new compatible string, then at least you need to document it
> so Documentation/devicetree/bindings/serial/amlogic,meson-uart.yaml need to be updated
> 
> but my qeustion here, why bother introducing new compatible string if nothing
> changed with the compatible data? given the uart is same IP with g12a, can't we just
> use "amlogic,meson-g12-uart" for this? no only it will reduce the structure length of
> meson_uart_dt_match[], but also relieve maintainer's review burden?

https://elixir.bootlin.com/linux/v6.1-rc1/source/Documentation/devicetree/bindings/writing-bindings.rst#L42

Best regards,
Krzysztof