summaryrefslogtreecommitdiffstats
path: root/Documentation/devicetree/bindings/input/gpio-matrix-keypad.txt
diff options
context:
space:
mode:
Diffstat (limited to '')
-rw-r--r--Documentation/devicetree/bindings/input/gpio-matrix-keypad.txt49
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>;
+ };