From: Krzysztof Kozlowski Date: Sun, 13 Jul 2025 12:46:38 +0000 (+0200) Subject: docs: dt: writing-bindings: Document discouraged instance IDs X-Git-Url: http://git.ipfire.org/cgi-bin/gitweb.cgi?a=commitdiff_plain;h=6a57cf210711c068a650bd86acae4a88303dfd5d;p=thirdparty%2Flinux.git docs: dt: writing-bindings: Document discouraged instance IDs Document established Devicetree bindings maintainers review practice: instance indexes, either as properties or as custom new OF alias, are not accepted. Recommended way is to use, depending on the situation/hardware: different compatible, cell arguments or syscon phandle arguments. Signed-off-by: Krzysztof Kozlowski Reviewed-by: Conor Dooley Link: https://lore.kernel.org/r/20250713-dt-bindings-docs-v2-3-672c898054ae@linaro.org Signed-off-by: Rob Herring (Arm) --- diff --git a/Documentation/devicetree/bindings/writing-bindings.rst b/Documentation/devicetree/bindings/writing-bindings.rst index e63de88385b5b..f8e0293a7c062 100644 --- a/Documentation/devicetree/bindings/writing-bindings.rst +++ b/Documentation/devicetree/bindings/writing-bindings.rst @@ -105,6 +105,11 @@ Typical cases and caveats - "syscon" is not a generic property. Use vendor and type, e.g. "vendor,power-manager-syscon". +- Do not add instance index (IDs) properties or custom OF aliases. If the + devices have different programming model, they might need different + compatibles. If such devices use some other device in a different way, e.g. + they program the phy differently, use cell/phandle arguments. + - Bindings files should be named like compatible: vendor,device.yaml. In case of multiple compatibles in the binding, use one of the fallbacks or a more generic name, yet still matching compatible style.