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References: <20231116181218.18886-1-krzysztof.kozlowski@linaro.org>
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From:   Geert Uytterhoeven <geert@linux-m68k.org>
Date:   Thu, 16 Nov 2023 22:32:17 +0100
Message-ID: <CAMuHMdVvAN9YcS4XsyinC1+WfAt0YwdNjv_pCpnfBpmGFeXtRg@mail.gmail.com>
Subject: Re: [PATCH] docs: dt-bindings: add DTS Coding Style document
To:     Krzysztof Kozlowski <krzysztof.kozlowski@linaro.org>
Cc:     Rob Herring <robh+dt@kernel.org>,
        Krzysztof Kozlowski <krzysztof.kozlowski+dt@linaro.org>,
        Conor Dooley <conor+dt@kernel.org>, devicetree@vger.kernel.org,
        linux-kernel@vger.kernel.org,
        AngeloGioacchino Del Regno 
        <angelogioacchino.delregno@collabora.com>,
        Arnd Bergmann <arnd@arndb.de>,
        Bjorn Andersson <andersson@kernel.org>,
        Heiko Stuebner <heiko@sntech.de>,
        Konrad Dybcio <konrad.dybcio@linaro.org>,
        Matthias Brugger <matthias.bgg@gmail.com>,
        Michal Simek <michal.simek@amd.com>,
        Neil Armstrong <neil.armstrong@linaro.org>,
        Nishanth Menon <nm@ti.com>, Olof Johansson <olof@lixom.net>
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Hi Krzysztof,

On Thu, Nov 16, 2023 at 7:12 PM Krzysztof Kozlowski
<krzysztof.kozlowski@linaro.org> wrote>
> Document preferred coding style for Devicetree sources (DTS and DTSI),
> to bring consistency among all (sub)architectures and ease in reviews.

> Signed-off-by: Krzysztof Kozlowski <krzysztof.kozlowski@linaro.org>

Thanks for your patch!

> --- a/Documentation/devicetree/bindings/index.rst
> +++ b/Documentation/devicetree/bindings/index.rst

> +Order of Nodes
> +--------------
> +
> +1. Nodes within any bus, thus using unit addresses for children, shall be
> +   ordered incrementally by unit address.

In Renesas DTS files, we have an (unwritten) additional rule: when there
are multiple nodes of the same type, they do not follow the global
ordering by unit-address, but are grouped together.
E.g. the second and any subsequent serial ports are always listed
immediately after the first serial port.

> +2. Nodes without unit addresses should be ordered alpha-numerically.
> +
> +3. When extending nodes in board DTS via &label, the entries should be ordered
> +   alpha-numerically.


> +Order of Properties in Device Node
> +----------------------------------
> +
> +Following order of properties in device nodes is preferred:
> +
> +1. compatible
> +2. reg
> +3. ranges
> +4. All properties with values
> +5. Boolean properties
> +6. status (if applicable)

There must be a lank line between properties and child nodes?

And once we have a documented coding style, the next long-standing item
from our wishlist would be a script to sort the contents of a DTS file
according to the rules ;-)

Gr{oetje,eeting}s,

                        Geert

-- 
Geert Uytterhoeven -- There's lots of Linux beyond ia32 -- geert@linux-m68k.org

In personal conversations with technical people, I call myself a hacker. But
when I'm talking to journalists I just say "programmer" or something like that.
                                -- Linus Torvalds