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gpio-kbd-matrix

Note

An implementation of a driver matching this compatible is available in drivers/input/input_gpio_kbd_matrix.c.

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;
};

Properties

Properties not inherited from the base binding file.

Name	Type	Details
`row-gpios`	`phandle-array`	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). This property is required.
`col-gpios`	`phandle-array`	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. This property is required.
`col-drive-inactive`	`boolean`	If enabled, unselected column GPIOs will be driven to inactive state. Default to configure unselected column GPIOs to high impedance.
`idle-mode`	`string`	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. Default value: `interrupt` Legal values: `'interrupt'`, `'poll'`, `'scan'`
`poll-period-ms`	`int`	Defines the poll period in msecs between between matrix scans, set to 0 to never exit poll mode. Defaults to 5ms if unspecified. Default value: `5`
`poll-timeout-ms`	`int`	How long to wait before going from polling back to idle state. Defaults to 100ms if unspecified. Default value: `100`
`debounce-down-ms`	`int`	Debouncing time for a key press event. Defaults to 10ms if unspecified. Default value: `10`
`debounce-up-ms`	`int`	Debouncing time for a key release event. Defaults to 20ms if unspecified. Default value: `20`
`settle-time-us`	`int`	Delay between setting column output and reading the row values. Defaults to 50us if unspecified. Default value: `50`
`actual-key-mask`	`array`	Keyboard scanning mask. For each keyboard column, specify which keyboard rows actually exist. Can be used to avoid triggering the ghost detection on non existing keys. No masking by default, any combination is valid.
`no-ghostkey-check`	`boolean`	Ignore the ghost key checking in the driver if the diodes are used in the matrix hardware.

Properties inherited from the base binding file, which defines common properties that may be set on many nodes. Not all of these may apply to the “gpio-kbd-matrix” compatible.

Name	Type	Details
`status`	`string`	indicates the operational status of a device Legal values: `'ok'`, `'okay'`, `'disabled'`, `'reserved'`, `'fail'`, `'fail-sss'` See Important properties for more information.
`compatible`	`string-array`	compatible strings This property is required. See Important properties for more information.
`reg`	`array`	register space See Important properties for more information.
`reg-names`	`string-array`	name of each register space
`interrupts`	`array`	interrupts for device See Important properties for more information.
`interrupts-extended`	`compound`	extended interrupt specifier for device
`interrupt-names`	`string-array`	name of each interrupt
`interrupt-parent`	`phandle`	phandle to interrupt controller node
`label`	`string`	Human readable string describing the device (used as device_get_binding() argument) See Important properties for more information. This property is deprecated.
`clocks`	`phandle-array`	Clock gate information
`clock-names`	`string-array`	name of each clock
`#address-cells`	`int`	number of address cells in reg property
`#size-cells`	`int`	number of size cells in reg property
`dmas`	`phandle-array`	DMA channels specifiers
`dma-names`	`string-array`	Provided names of DMA channel specifiers
`io-channels`	`phandle-array`	IO channels specifiers
`io-channel-names`	`string-array`	Provided names of IO channel specifiers
`mboxes`	`phandle-array`	mailbox / IPM channels specifiers
`mbox-names`	`string-array`	Provided names of mailbox / IPM channel specifiers
`power-domains`	`phandle-array`	Power domain specifiers
`power-domain-names`	`string-array`	Provided names of power domain specifiers
`#power-domain-cells`	`int`	Number of cells in power-domains property
`zephyr,deferred-init`	`boolean`	Do not initialize device automatically on boot. Device should be manually initialized using device_init().
`wakeup-source`	`boolean`	Property to identify that a device can be used as wake up source. When this property is provided a specific flag is set into the device that tells the system that the device is capable of wake up the system. Wake up capable devices are disabled (interruptions will not wake up the system) by default but they can be enabled at runtime if necessary.
`zephyr,pm-device-runtime-auto`	`boolean`	Automatically configure the device for runtime power management after the init function runs.
`zephyr,disabling-power-states`	`phandles`	List of power states that will disable this device power.