Commit 9d60648c authored by José Expósito's avatar José Expósito Committed by Jiri Kosina
Browse files

HID: magicmouse: high-resolution scroll threshold 



In order to avoid triggering involuntary high-resolution scroll events
due to tiny touch movement deltas, add a movement threshold.

The value chosen for the threshold, about 1.5 ~ 2 mm, is similar to the
threshold used on touchpads by libinput (see libinput
evdev-mt-touchpad-gestures.c) to try to keep the scroll experience
consistent.

Signed-off-by: default avatarJosé Expósito <jose.exposito89@gmail.com>
Signed-off-by: default avatarJiri Kosina <jkosina@suse.cz>
parent d4b9f10a

drivers/hid/hid-magicmouse.c

+23 −2
Original line number Diff line number Diff line
@@ -71,6 +71,7 @@ MODULE_PARM_DESC(report_undeciphered, "Report undeciphered multi-touch state fie 
/* Number of high-resolution events for each low-resolution detent. */

#define SCROLL_HR_STEPS 10

#define SCROLL_HR_MULT (120 / SCROLL_HR_STEPS)

#define SCROLL_HR_THRESHOLD 90 /* units */

#define SCROLL_ACCEL_DEFAULT 7



/* Touch surface information. Dimension is in hundredths of a mm, min and max
@@ -132,6 +133,8 @@ struct magicmouse_sc { 
		short scroll_x_hr;

		short scroll_y_hr;

		u8 size;

		bool scroll_x_active;

		bool scroll_y_active;

	} touches[16];

	int tracking_ids[16];
@@ -265,6 +268,8 @@ static void magicmouse_emit_touch(struct magicmouse_sc *msc, int raw_id, u8 *tda 
			msc->touches[id].scroll_y = y;

			msc->touches[id].scroll_x_hr = x;

			msc->touches[id].scroll_y_hr = y;

			msc->touches[id].scroll_x_active = false;

			msc->touches[id].scroll_y_active = false;



			/* Reset acceleration after half a second. */

			if (scroll_acceleration && time_before(now,
@@ -292,8 +297,16 @@ static void magicmouse_emit_touch(struct magicmouse_sc *msc, int raw_id, u8 *tda 
				input_report_rel(input, REL_WHEEL, step_y);

			}



			if (!msc->touches[id].scroll_x_active &&

			    abs(step_x_hr) > SCROLL_HR_THRESHOLD) {

				msc->touches[id].scroll_x_active = true;

				msc->touches[id].scroll_x_hr = x;

				step_x_hr = 0;

			}



			step_x_hr /= step_hr;

			if (step_x_hr != 0) {

			if (step_x_hr != 0 &&

			    msc->touches[id].scroll_x_active) {

				msc->touches[id].scroll_x_hr -= step_x_hr *

					step_hr;

				input_report_rel(input,
@@ -301,8 +314,16 @@ static void magicmouse_emit_touch(struct magicmouse_sc *msc, int raw_id, u8 *tda 
						 -step_x_hr * SCROLL_HR_MULT);

			}



			if (!msc->touches[id].scroll_y_active &&

			    abs(step_y_hr) > SCROLL_HR_THRESHOLD) {

				msc->touches[id].scroll_y_active = true;

				msc->touches[id].scroll_y_hr = y;

				step_y_hr = 0;

			}



			step_y_hr /= step_hr;

			if (step_y_hr != 0) {

			if (step_y_hr != 0 &&

			    msc->touches[id].scroll_y_active) {

				msc->touches[id].scroll_y_hr -= step_y_hr *

					step_hr;

				input_report_rel(input,