# Copyright (c) 2022 Silicon Labs # SPDX-License-Identifier: Apache-2.0 description: | The Silabs pin controller is a singleton node responsible for controlling pin function selection and pin properties. For example, you can use this node to route UART0 RX to pin P0.1 and enable the pull-up resistor on the pin. The node has the 'pinctrl' node label set in your SoC's devicetree, so you can modify it like this: &pinctrl { /* your modifications go here */ }; All device pin configurations should be placed in child nodes of the 'pinctrl' node, as shown in this example: /* You can put this in places like a board-pinctrl.dtsi file in * your board directory, or a devicetree overlay in your application. */ &pinctrl { /* configuration for usart0 device, default state */ usart0_default: usart0_default { /* group 1 ('group1' name is arbitrary) */ group1 { /* configure P0.1 as UART_TX and P0.2 as UART_RTS */ psels = , ; }; /* group 2 */ group2 { /* configure P0.3 as UART_RX and P0.4 as UART_CTS */ psels = , ; }; }; }; The 'usart0_default' child node encodes the pin configurations for a particular state of a device; in this case, the default (that is, active) state. You would specify the low-power configuration for the same device in a separate child node. As shown, pin configurations are organized in groups within each child node. Each group can specify a list of pin function selections in the 'psels' property. The GECKO_PSEL macro is used to specify a pin function selection. Available pin functions can be found in the include/dt-bindings/pinctrl/gecko-pinctrl.h header file. To link this pin configuration with a device, use a pinctrl-N property for some number N, like this example you could place in your board's DTS file: #include "board-pinctrl.dtsi" &usart0 { pinctrl-0 = <&usart0_default>; pinctrl-names = "default"; }; compatible: "silabs,gecko-pinctrl" include: base.yaml child-binding: description: | Silabs pin controller pin configuration state nodes. include: pincfg-node.yaml child-binding: description: | Silabs pin controller pin configuration group. properties: psels: required: true type: array description: | An array of pins sharing the same group properties. The pins should be defined using the GECKO_PSEL utility macro that encodes the port, pin and function.