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edited Feb 6 at 14:22

alpd4

Adding MCP23017 to device-tree and accessing ICs connected to epxanderexpander

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asked Feb 6 at 14:03

alpd4

Adding MCP23017 to device-tree and accessing ICs connected to epxander

I try access multiple ICs via I2C over the MCP23017 I/O Expander for a custom embedded board. I know ICs I2C adresses.

How should I add the MCP23017 to the device-tree?

I think I need to add the ICs as child nodes under MCP2301 in device-tree, but I don't know how to do it.

There are a device-tree example below. Will Linux detect the ICs when implemented this way? What is the easiest way to access ICs?

&i2c1 { clock-frequency = <100000>; pinctrl-names = "default"; pinctrl-0 = <&pinctrl_i2c_1>; status = "okay"; /* mcp23017 I2C IO Expander */ gpio_ex3: gpio_mcp@20 { compatible = "microchip,mcp23017"; gpio-controller; #gpio-cells = <2>; reg = <0x20>; status = "okay"; };