# Copyright 2023 Google LLC # SPDX-License-Identifier: Apache-2.0 description: | GPIO based keyboard matrix input device Implement an input device for a GPIO based keyboard matrix. Example configuration: kbd-matrix { compatible = "gpio-kbd-matrix"; row-gpios = <&gpio0 0 (GPIO_PULL_UP | GPIO_ACTIVE_LOW)>, <&gpio0 1 (GPIO_PULL_UP | GPIO_ACTIVE_LOW)>; col-gpios = <&gpio0 2 GPIO_ACTIVE_LOW>, <&gpio0 3 GPIO_ACTIVE_LOW>, <&gpio0 4 GPIO_ACTIVE_LOW>; no-ghostkey-check; }; compatible: "gpio-kbd-matrix" include: - name: kbd-matrix-common.yaml property-blocklist: - row-size - col-size properties: row-gpios: type: phandle-array required: true description: | GPIO for the keyboard matrix rows, up to 8 different GPIOs. All row GPIO pins must have interrupt support if idle-mode is set to "interrupt" (default). col-gpios: type: phandle-array required: true description: | GPIO for the keyboard matrix columns, supports up to 32 different GPIOs. When unselected, this pin will be either driven to inactive state or configured to high impedance (input) depending on the col-drive-inactive property. col-drive-inactive: type: boolean description: | If enabled, unselected column GPIOs will be driven to inactive state. Default to configure unselected column GPIOs to high impedance. idle-mode: type: string default: "interrupt" enum: - "interrupt" - "poll" - "scan" description: | Controls the driver behavior on idle, "interrupt" waits for a new key press using GPIO interrupts on the row lines, "poll" periodically polls the row lines with all the columns selected, "scan" just keep scanning the matrix continuously, requires "poll-timeout-ms" to be set to 0.