From 374f8436ff3a450a2f95a0c1910a0b17212cede1 Mon Sep 17 00:00:00 2001 From: Peter Rosin Date: Fri, 8 Jul 2016 12:13:12 +0200 Subject: [PATCH] dt-bindings: i2c: add support for 'i2c-mux' subnode Similar to the new optional 'i2c-bus' subnode from Jon Hunter, this adds an optional 'i2c-mux' subnode, for similar reasons. I.e. it is bad of the i2c mux core to assume that any subnode of an i2c mux device is a potential (when the 'reg' property matches) i2c-mux child bus, given that i2c mux devices might do more than mux i2c traffic. So, if an 'i2c-mux' subnode is present, dictate that all i2c-mux child buses exist beneath that subnode. Acked-by: Rob Herring Reviewed-by: Wolfram Sang Signed-off-by: Peter Rosin --- .../devicetree/bindings/i2c/i2c-mux.txt | 23 +++++++++++++++---- 1 file changed, 18 insertions(+), 5 deletions(-) diff --git a/Documentation/devicetree/bindings/i2c/i2c-mux.txt b/Documentation/devicetree/bindings/i2c/i2c-mux.txt index af84cce5cd7b..212e6779dc5c 100644 --- a/Documentation/devicetree/bindings/i2c/i2c-mux.txt +++ b/Documentation/devicetree/bindings/i2c/i2c-mux.txt @@ -2,19 +2,32 @@ Common i2c bus multiplexer/switch properties. An i2c bus multiplexer/switch will have several child busses that are numbered uniquely in a device dependent manner. The nodes for an i2c bus -multiplexer/switch will have one child node for each child -bus. +multiplexer/switch will have one child node for each child bus. -Required properties: +Optional properties: +- #address-cells = <1>; + This property is required is the i2c-mux child node does not exist. + +- #size-cells = <0>; + This property is required is the i2c-mux child node does not exist. + +- i2c-mux + For i2c multiplexers/switches that have child nodes that are a mixture + of both i2c child busses and other child nodes, the 'i2c-mux' subnode + can be used for populating the i2c child busses. If an 'i2c-mux' + subnode is present, only subnodes of this will be considered as i2c + child busses. + +Required properties for the i2c-mux child node: - #address-cells = <1>; - #size-cells = <0>; -Required properties for child nodes: +Required properties for i2c child bus nodes: - #address-cells = <1>; - #size-cells = <0>; - reg : The sub-bus number. -Optional properties for child nodes: +Optional properties for i2c child bus nodes: - Other properties specific to the multiplexer/switch hardware. - Child nodes conforming to i2c bus binding -- GitLab