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-rw-r--r-- | Documentation/devicetree/bindings/input/gpio-matrix-keypad.txt | 49 |
1 files changed, 49 insertions, 0 deletions
diff --git a/Documentation/devicetree/bindings/input/gpio-matrix-keypad.txt b/Documentation/devicetree/bindings/input/gpio-matrix-keypad.txt new file mode 100644 index 000000000..570dc10f0 --- /dev/null +++ b/Documentation/devicetree/bindings/input/gpio-matrix-keypad.txt @@ -0,0 +1,49 @@ +* GPIO driven matrix keypad device tree bindings + +GPIO driven matrix keypad is used to interface a SoC with a matrix keypad. +The matrix keypad supports multiple row and column lines, a key can be +placed at each intersection of a unique row and a unique column. The matrix +keypad can sense a key-press and key-release by means of GPIO lines and +report the event using GPIO interrupts to the cpu. + +Required Properties: +- compatible: Should be "gpio-matrix-keypad" +- row-gpios: List of gpios used as row lines. The gpio specifier + for this property depends on the gpio controller to + which these row lines are connected. +- col-gpios: List of gpios used as column lines. The gpio specifier + for this property depends on the gpio controller to + which these column lines are connected. +- linux,keymap: The definition can be found at + bindings/input/matrix-keymap.txt + +Optional Properties: +- linux,no-autorepeat: do no enable autorepeat feature. +- wakeup-source: use any event on keypad as wakeup event. + (Legacy property supported: "linux,wakeup") +- debounce-delay-ms: debounce interval in milliseconds +- col-scan-delay-us: delay, measured in microseconds, that is needed + before we can scan keypad after activating column gpio +- drive-inactive-cols: drive inactive columns during scan, + default is to turn inactive columns into inputs. + +Example: + matrix-keypad { + compatible = "gpio-matrix-keypad"; + debounce-delay-ms = <5>; + col-scan-delay-us = <2>; + + row-gpios = <&gpio2 25 0 + &gpio2 26 0 + &gpio2 27 0>; + + col-gpios = <&gpio2 21 0 + &gpio2 22 0>; + + linux,keymap = <0x0000008B + 0x0100009E + 0x02000069 + 0x0001006A + 0x0101001C + 0x0201006C>; + }; |