This change adds support for specifying device tree buttons emitting abs/rel events. ABS events were previously supported, but only via platform data, so add the missing device tree property to allow axis values to be emitted with abs/rel events. Also emit 0 on button releases for REL and ABS keys. This is a must-have for supporting digital joysticks, and aligns the driver whith gpio-keys-polled. Finally, report min/max values for abs axes to the input framework. Signed-off-by: Hans Holmberg <hans@xxxxxxxxxxxxxxxxx> --- RFC because it alters the behaviour of abs-buttons making them un-sticky, reporting 0 on button releases - just like gpio-keys-polled. FWIW, i've looked through the in-tree board files and not found a single occurence of abs gpio-buttons. Changes since v1: * Corrected cc list - now the mailing lists are looped in. .../devicetree/bindings/input/gpio-keys.txt | 50 +++++++++++++++++++++- drivers/input/keyboard/gpio_keys.c | 29 +++++++++++-- 2 files changed, 75 insertions(+), 4 deletions(-) diff --git a/Documentation/devicetree/bindings/input/gpio-keys.txt b/Documentation/devicetree/bindings/input/gpio-keys.txt index a949404..1b53eed 100644 --- a/Documentation/devicetree/bindings/input/gpio-keys.txt +++ b/Documentation/devicetree/bindings/input/gpio-keys.txt @@ -22,6 +22,13 @@ both at the same time. Specifying both properties is allowed. 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 sent for events this button generates when pressed. + EV_ABS/EV_REL axis will generate an event with a value of 0 when + all buttons with linux,input-type == type and linux,code == axis + are released. This value is interpreted as a signed 32 bit value, + e.g. to make a button generate a value of -1 use: + linux,input-value = <0xffffffff>; /* -1 */ - debounce-interval: Debouncing interval time in milliseconds. If not specified defaults to 5. - wakeup-source: Boolean, button can wake-up the system. @@ -47,4 +54,45 @@ Example nodes: linux,code = <108>; interrupts = <1 IRQ_TYPE_LEVEL_HIGH 7>; }; - ... + ... + + gpio-joystick: { + compatible = "gpio-keys"; + + pinctrl-names = "default"; + pinctrl-0 = <&my_pins>; + + up { + gpios = <&gpio 26 1>; + linux,input-type = <EV_ABS>; + linux,code = <ABS_Y>; + linux,input-value = <0xffffffff>; + }; + + down { + gpios = <&gpio 13 1>; + linux,input-type = <EV_ABS>; + linux,code = <ABS_Y>; + linux,input-value = <1>; + }; + + left { + gpios = <&gpio 6 1>; + linux,input-type = <EV_ABS>; + linux,code = <ABS_X>; + linux,input-value = <0xffffffff>; + }; + + right { + gpios = <&gpio 5 1>; + linux,input-type = <EV_ABS>; + linux,code = <ABS_X>; + linux,input-value = <0x1>; + }; + + trigger_button { + gpios = <&gpio 12 1>; + linux,code = <BTN_TRIGGER>; + }; + }; + ... diff --git a/drivers/input/keyboard/gpio_keys.c b/drivers/input/keyboard/gpio_keys.c index 9c92cdf..06d6902 100644 --- a/drivers/input/keyboard/gpio_keys.c +++ b/drivers/input/keyboard/gpio_keys.c @@ -370,9 +370,11 @@ static void gpio_keys_gpio_report_event(struct gpio_button_data *bdata) return; } - if (type == EV_ABS) { + if (type == EV_ABS || type == EV_REL) { if (state) input_event(input, type, button->code, button->value); + else + input_event(input, type, button->code, 0); } else { input_event(input, type, *bdata->code, state); } @@ -584,6 +586,14 @@ static int gpio_keys_setup_key(struct platform_device *pdev, *bdata->code = button->code; input_set_capability(input, button->type ?: EV_KEY, *bdata->code); + if (button->type == EV_ABS) { + if (input_abs_get_max(input, button->code) < button->value) + input_abs_set_max(input, button->code, button->value); + + if (input_abs_get_min(input, button->code) > button->value) + input_abs_set_min(input, button->code, button->value); + } + /* * Install custom action to cancel release timer and * workqueue item. @@ -667,6 +677,7 @@ static void gpio_keys_close(struct input_dev *input) struct gpio_keys_button *button; struct fwnode_handle *child; int nbuttons; + int error; nbuttons = device_get_child_node_count(dev); if (nbuttons == 0) @@ -701,9 +712,21 @@ static void gpio_keys_close(struct input_dev *input) fwnode_property_read_string(child, "label", &button->desc); - if (fwnode_property_read_u32(child, "linux,input-type", - &button->type)) + error = fwnode_property_read_u32(child, "linux,input-type", + &button->type); + if (error) { button->type = EV_KEY; + } else { + error = fwnode_property_read_u32(child, + "linux,input-value", + &button->value); + if ((button->type == EV_ABS || button->type == EV_REL) + && error) { + dev_err(dev, + "EV_ABS/EV_REL button without value\n"); + return ERR_PTR(-EINVAL); + } + } button->wakeup = fwnode_property_read_bool(child, "wakeup-source") || -- 1.9.1 -- 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