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Diffstat (limited to 'Documentation/devicetree/bindings/i2c/i2c-mux-gpmux.txt')
-rw-r--r-- | Documentation/devicetree/bindings/i2c/i2c-mux-gpmux.txt | 99 |
1 files changed, 0 insertions, 99 deletions
diff --git a/Documentation/devicetree/bindings/i2c/i2c-mux-gpmux.txt b/Documentation/devicetree/bindings/i2c/i2c-mux-gpmux.txt deleted file mode 100644 index 8b444b94e92f..000000000000 --- a/Documentation/devicetree/bindings/i2c/i2c-mux-gpmux.txt +++ /dev/null @@ -1,99 +0,0 @@ -General Purpose I2C Bus Mux - -This binding describes an I2C bus multiplexer that uses a mux controller -from the mux subsystem to route the I2C signals. - - .-----. .-----. - | dev | | dev | - .------------. '-----' '-----' - | SoC | | | - | | .--------+--------' - | .------. | .------+ child bus A, on MUX value set to 0 - | | I2C |-|--| Mux | - | '------' | '--+---+ child bus B, on MUX value set to 1 - | .------. | | '----------+--------+--------. - | | MUX- | | | | | | - | | Ctrl |-|-----+ .-----. .-----. .-----. - | '------' | | dev | | dev | | dev | - '------------' '-----' '-----' '-----' - -Required properties: -- compatible: i2c-mux -- i2c-parent: The phandle of the I2C bus that this multiplexer's master-side - port is connected to. -- mux-controls: The phandle of the mux controller to use for operating the - mux. -* Standard I2C mux properties. See i2c-mux.txt in this directory. -* I2C child bus nodes. See i2c-mux.txt in this directory. The sub-bus number - is also the mux-controller state described in ../mux/mux-controller.txt - -Optional properties: -- mux-locked: If present, explicitly allow unrelated I2C transactions on the - parent I2C adapter at these times: - + during setup of the multiplexer - + between setup of the multiplexer and the child bus I2C transaction - + between the child bus I2C transaction and releasing of the multiplexer - + during releasing of the multiplexer - However, I2C transactions to devices behind all I2C multiplexers connected - to the same parent adapter that this multiplexer is connected to are blocked - for the full duration of the complete multiplexed I2C transaction (i.e. - including the times covered by the above list). - If mux-locked is not present, the multiplexer is assumed to be parent-locked. - This means that no unrelated I2C transactions are allowed on the parent I2C - adapter for the complete multiplexed I2C transaction. - The properties of mux-locked and parent-locked multiplexers are discussed - in more detail in Documentation/i2c/i2c-topology.rst. - -For each i2c child node, an I2C child bus will be created. They will -be numbered based on their order in the device tree. - -Whenever an access is made to a device on a child bus, the value set -in the relevant node's reg property will be set as the state in the -mux controller. - -Example: - mux: mux-controller { - compatible = "gpio-mux"; - #mux-control-cells = <0>; - - mux-gpios = <&pioA 0 GPIO_ACTIVE_HIGH>, - <&pioA 1 GPIO_ACTIVE_HIGH>; - }; - - i2c-mux { - compatible = "i2c-mux"; - mux-locked; - i2c-parent = <&i2c1>; - - mux-controls = <&mux>; - - #address-cells = <1>; - #size-cells = <0>; - - i2c@1 { - reg = <1>; - #address-cells = <1>; - #size-cells = <0>; - - ssd1307: oled@3c { - compatible = "solomon,ssd1307fb-i2c"; - reg = <0x3c>; - pwms = <&pwm 4 3000>; - reset-gpios = <&gpio2 7 1>; - reset-active-low; - }; - }; - - i2c@3 { - reg = <3>; - #address-cells = <1>; - #size-cells = <0>; - - pca9555: pca9555@20 { - compatible = "nxp,pca9555"; - gpio-controller; - #gpio-cells = <2>; - reg = <0x20>; - }; - }; - }; |