[PATCH libinput 3/4] evdev: add support for wheel tilt

[Peter Hutterer]

This is added on top of the click angle handling, so the actual axis values
simply fall back onto whatever is set by udev, including the default fallbacks
to 15 and whatnot.

Signed-off-by: Peter Hutterer <peter.hutterer at who-t.net>
---
 src/evdev.c            | 31 +++++++++++++++++++++++++++++--
 src/evdev.h            |  2 ++
 src/libinput-private.h |  5 +++++
 3 files changed, 36 insertions(+), 2 deletions(-)

diff --git a/src/evdev.c b/src/evdev.c
index 500a0f8..0bb92ab 100644
--- a/src/evdev.c
+++ b/src/evdev.c
@@ -958,6 +958,7 @@ fallback_process_relative(struct fallback_dispatch *dispatch,
 {
 	struct normalized_coords wheel_degrees = { 0.0, 0.0 };
 	struct discrete_coords discrete = { 0.0, 0.0 };
+	enum libinput_pointer_axis_source source;
 
 	if (fallback_reject_relative(device, e, time))
 		return;
@@ -980,11 +981,16 @@ fallback_process_relative(struct fallback_dispatch *dispatch,
 		wheel_degrees.y = -1 * e->value *
 					device->scroll.wheel_click_angle.x;
 		discrete.y = -1 * e->value;
+
+		source = device->scroll.is_tilt.vertical ?
+				LIBINPUT_POINTER_AXIS_SOURCE_WHEEL_TILT:
+				LIBINPUT_POINTER_AXIS_SOURCE_WHEEL;
+
 		evdev_notify_axis(
 			device,
 			time,
 			AS_MASK(LIBINPUT_POINTER_AXIS_SCROLL_VERTICAL),
-			LIBINPUT_POINTER_AXIS_SOURCE_WHEEL,
+			source,
 			&wheel_degrees,
 			&discrete);
 		break;
@@ -993,11 +999,16 @@ fallback_process_relative(struct fallback_dispatch *dispatch,
 		wheel_degrees.x = e->value *
 					device->scroll.wheel_click_angle.y;
 		discrete.x = e->value;
+
+		source = device->scroll.is_tilt.horizontal ?
+				LIBINPUT_POINTER_AXIS_SOURCE_WHEEL_TILT:
+				LIBINPUT_POINTER_AXIS_SOURCE_WHEEL;
+
 		evdev_notify_axis(
 			device,
 			time,
 			AS_MASK(LIBINPUT_POINTER_AXIS_SCROLL_HORIZONTAL),
-			LIBINPUT_POINTER_AXIS_SOURCE_WHEEL,
+			source,
 			&wheel_degrees,
 			&discrete);
 		break;
@@ -2110,6 +2121,21 @@ evdev_read_wheel_click_props(struct evdev_device *device)
 	return angles;
 }
 
+static inline struct wheel_tilt_flags
+evdev_read_wheel_tilt_props(struct evdev_device *device)
+{
+	struct wheel_tilt_flags flags;
+
+	flags.vertical = parse_udev_flag(device,
+					 device->udev_device,
+					 "MOUSE_WHEEL_TILT_VERTICAL");
+
+	flags.horizontal = parse_udev_flag(device,
+					 device->udev_device,
+					 "MOUSE_WHEEL_TILT_HORIZONTAL");
+	return flags;
+}
+
 static inline int
 evdev_get_trackpoint_dpi(struct evdev_device *device)
 {
@@ -2847,6 +2873,7 @@ evdev_device_create(struct libinput_seat *seat,
 	device->scroll.direction = 0;
 	device->scroll.wheel_click_angle =
 		evdev_read_wheel_click_props(device);
+	device->scroll.is_tilt = evdev_read_wheel_tilt_props(device);
 	device->model_flags = evdev_read_model_flags(device);
 	device->dpi = DEFAULT_MOUSE_DPI;
 
diff --git a/src/evdev.h b/src/evdev.h
index b5a54a2..cd5697e 100644
--- a/src/evdev.h
+++ b/src/evdev.h
@@ -197,6 +197,8 @@ struct evdev_device {
 
 		/* angle per REL_WHEEL click in degrees */
 		struct wheel_angle wheel_click_angle;
+
+		struct wheel_tilt_flags is_tilt;
 	} scroll;
 
 	struct {
diff --git a/src/libinput-private.h b/src/libinput-private.h
index 52f129a..99c8057 100644
--- a/src/libinput-private.h
+++ b/src/libinput-private.h
@@ -93,6 +93,11 @@ struct phys_coords {
 	double y;
 };
 
+/* A pair of tilt flags */
+struct wheel_tilt_flags {
+	bool vertical, horizontal;
+};
+
 struct tablet_axes {
 	struct device_coords point;
 	struct normalized_coords delta;
-- 
2.9.3