An extension of the RTL9300 SoC is to support multiplexing by selecting the SDA pins that are being used dynamically. Add a binding that allows us to describe hardware that makes use of this. Signed-off-by: Chris Packham <chris.packham@xxxxxxxxxxxxxxxxxxx> --- .../bindings/i2c/realtek,rtl9300-i2c-mux.yaml | 82 +++++++++++++++++++ MAINTAINERS | 1 + 2 files changed, 83 insertions(+) create mode 100644 Documentation/devicetree/bindings/i2c/realtek,rtl9300-i2c-mux.yaml diff --git a/Documentation/devicetree/bindings/i2c/realtek,rtl9300-i2c-mux.yaml b/Documentation/devicetree/bindings/i2c/realtek,rtl9300-i2c-mux.yaml new file mode 100644 index 000000000000..a64879d0fda7 --- /dev/null +++ b/Documentation/devicetree/bindings/i2c/realtek,rtl9300-i2c-mux.yaml @@ -0,0 +1,82 @@ +# SPDX-License-Identifier: (GPL-2.0-only OR BSD-2-Clause) +%YAML 1.2 +--- +$id: http://devicetree.org/schemas/i2c/realtek,rtl9300-i2c-mux.yaml# +$schema: http://devicetree.org/meta-schemas/core.yaml# + +title: Realtek RTL I2C Multiplexer + +maintainers: + - Chris Packham <chris.packham@xxxxxxxxxxxxxxxxxxx> + +description: | + The I2C controllers on the RTL9300 support a level of multiplexing. In the + simple case the rtl9300-i2c binding can provide a single SDA pin per + controller. This binding allows a more than one SDA line to be used per + controller providing a level of multiplexing. + +properties: + compatible: + const: realtek,rtl9300-i2c-mux + + i2c-parent: + description: phandle of the I2C bus controller that this multiplexer + operates on. + $ref: /schemas/types.yaml#/definitions/phandle + +allOf: + - $ref: i2c-mux.yaml + +unevaluatedProperties: false + +required: + - compatible + - i2c-parent + +examples: + - | + switch@1b000000 { + compatible = "realtek,rtl9302c-switch", "syscon", "simple-mfd"; + reg = <0x1b000000 0x10000>; + + i2c0: i2c@36c { + compatible = "realtek,rtl9300-i2c"; + realtek,control-offset = <0x36c>; + realtek,global-control-offset = <0x384>; + #address-cells = <1>; + #size-cells = <0>; + }; + }; + + base { + i2c-mux { + compatible = "realtek,rtl9300-i2c-mux"; + #address-cells = <1>; + #size-cells = <0>; + i2c-parent = <&i2c0>; + + i2c@0 { + reg = <0>; + #address-cells = <1>; + #size-cells = <0>; + gpio@20 { + compatible = "nxp,pca9555"; + gpio-controller; + #gpio-cells = <2>; + reg = <0x20>; + }; + }; + + i2c@2 { + reg = <2>; + #address-cells = <1>; + #size-cells = <0>; + gpio@20 { + compatible = "nxp,pca9555"; + gpio-controller; + #gpio-cells = <2>; + reg = <0x20>; + }; + }; + }; + }; diff --git a/MAINTAINERS b/MAINTAINERS index 9e123e9839a5..178ac8a7e843 100644 --- a/MAINTAINERS +++ b/MAINTAINERS @@ -19891,6 +19891,7 @@ RTL9300 I2C DRIVER (rtl9300-i2c) M: Chris Packham <chris.packham@xxxxxxxxxxxxxxxxxxx> L: linux-i2c@xxxxxxxxxxxxxxx S: Maintained +F: Documentation/devicetree/bindings/i2c/realtek,rtl9300-i2c-mux.yaml F: Documentation/devicetree/bindings/i2c/realtek,rtl9300-i2c.yaml F: drivers/i2c/busses/i2c-rtl9300.c -- 2.46.1
