* GPIO driven matrix keypad device tree bindings
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GPIO driven matrix keypad is used to interface a SoC with a matrix keypad.
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The matrix keypad supports multiple row and column lines, a key can be
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placed at each intersection of a unique row and a unique column. The matrix
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keypad can sense a key-press and key-release by means of GPIO lines and
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report the event using GPIO interrupts to the cpu.
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Required Properties:
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- compatible: Should be "gpio-matrix-keypad"
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- row-gpios: List of gpios used as row lines. The gpio specifier
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for this property depends on the gpio controller to
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which these row lines are connected.
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- col-gpios: List of gpios used as column lines. The gpio specifier
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for this property depends on the gpio controller to
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which these column lines are connected.
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- linux,keymap: The definition can be found at
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bindings/input/matrix-keymap.txt
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Optional Properties:
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- linux,no-autorepeat: do no enable autorepeat feature.
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- wakeup-source: use any event on keypad as wakeup event.
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(Legacy property supported: "linux,wakeup")
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- debounce-delay-ms: debounce interval in milliseconds
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- col-scan-delay-us: delay, measured in microseconds, that is needed
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before we can scan keypad after activating column gpio
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- drive-inactive-cols: drive inactive columns during scan,
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default is to turn inactive columns into inputs.
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Example:
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matrix-keypad {
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compatible = "gpio-matrix-keypad";
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debounce-delay-ms = <5>;
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col-scan-delay-us = <2>;
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row-gpios = <&gpio2 25 0
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&gpio2 26 0
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&gpio2 27 0>;
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col-gpios = <&gpio2 21 0
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&gpio2 22 0>;
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linux,keymap = <0x0000008B
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0x0100009E
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0x02000069
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0x0001006A
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0x0101001C
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0x0201006C>;
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};
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