The devicetree binding for gpio-keys-polled already allows specifying what type of events (key / rel / abs) a button generates when pressed. But for rel / abs axis we also need to specify which value this specific gpio represents. One usecase is digital joysticks / direction-pads which are hooked up to gpio, in this case we've left and right buttons which we want to map to EV_ABS, ABS_X and we want generate events for left with a value of -1 and for right with a value of +1 (and similar for up / down and ABS_Y). Signed-off-by: Hans de Goede <hdegoede@xxxxxxxxxx> --- Documentation/devicetree/bindings/input/gpio-keys-polled.txt | 7 ++++++- 1 file changed, 6 insertions(+), 1 deletion(-) diff --git a/Documentation/devicetree/bindings/input/gpio-keys-polled.txt b/Documentation/devicetree/bindings/input/gpio-keys-polled.txt index 313abef..ab4b09b 100644 --- a/Documentation/devicetree/bindings/input/gpio-keys-polled.txt +++ b/Documentation/devicetree/bindings/input/gpio-keys-polled.txt @@ -13,11 +13,16 @@ Subnode properties: - gpios: OF device-tree gpio specification. - label: Descriptive name of the key. - - linux,code: Keycode to emit. + - linux,code: Key / Axis code to emit. Optional subnode-properties: - linux,input-type: Specify event type this button/key generates. If not specified defaults to <1> == EV_KEY. + - linux,input-value: If linux,input-type is EV_ABS or EV_REL then this + value is send for events this button generates when pressed. + EV_ABS axis will generate an event with a value of 0 when all + buttons with linux,input-type == EV_ABS and linux,code == axis + are released. - debounce-interval: Debouncing interval time in milliseconds. If not specified defaults to 5. - gpio-key,wakeup: Boolean, button can wake-up the system. -- 2.4.3 -- To unsubscribe from this list: send the line "unsubscribe devicetree" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
