HID: magicmouse: enable high-resolution scroll

The Magic Mouse, generations 1 and 2, doesn't have a physical scroll
wheel, instead, the REL_WHEEL and REL_HWHEEL events are emulated
when sliding a finger on the surface of the mouse.
However, the smooth movement of the finger is transformed into a step
based scroll on the screen, leading to a suboptimal user experience.

Emulate high-resolution scroll by sending REL_WHEEL_HI_RES and
REL_HWHEEL_HI_RES events so the scroll on the screen is closer to the
finger movement.

Signed-off-by: José Expósito <jose.exposito89@gmail.com>
Signed-off-by: Jiri Kosina <jkosina@suse.cz>
This commit is contained in:
José Expósito 2021-07-07 17:58:21 +02:00 committed by Jiri Kosina
parent df04fbe868
commit d4b9f10a0e

View File

@ -68,6 +68,9 @@ MODULE_PARM_DESC(report_undeciphered, "Report undeciphered multi-touch state fie
#define TOUCH_STATE_START 0x30
#define TOUCH_STATE_DRAG 0x40
/* 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_ACCEL_DEFAULT 7
/* Touch surface information. Dimension is in hundredths of a mm, min and max
@ -126,6 +129,8 @@ struct magicmouse_sc {
short y;
short scroll_x;
short scroll_y;
short scroll_x_hr;
short scroll_y_hr;
u8 size;
} touches[16];
int tracking_ids[16];
@ -248,12 +253,18 @@ static void magicmouse_emit_touch(struct magicmouse_sc *msc, int raw_id, u8 *tda
unsigned long now = jiffies;
int step_x = msc->touches[id].scroll_x - x;
int step_y = msc->touches[id].scroll_y - y;
int step_hr = ((64 - (int)scroll_speed) * msc->scroll_accel) /
SCROLL_HR_STEPS;
int step_x_hr = msc->touches[id].scroll_x_hr - x;
int step_y_hr = msc->touches[id].scroll_y_hr - y;
/* Calculate and apply the scroll motion. */
switch (state) {
case TOUCH_STATE_START:
msc->touches[id].scroll_x = x;
msc->touches[id].scroll_y = y;
msc->touches[id].scroll_x_hr = x;
msc->touches[id].scroll_y_hr = y;
/* Reset acceleration after half a second. */
if (scroll_acceleration && time_before(now,
@ -280,6 +291,24 @@ static void magicmouse_emit_touch(struct magicmouse_sc *msc, int raw_id, u8 *tda
msc->scroll_jiffies = now;
input_report_rel(input, REL_WHEEL, step_y);
}
step_x_hr /= step_hr;
if (step_x_hr != 0) {
msc->touches[id].scroll_x_hr -= step_x_hr *
step_hr;
input_report_rel(input,
REL_HWHEEL_HI_RES,
-step_x_hr * SCROLL_HR_MULT);
}
step_y_hr /= step_hr;
if (step_y_hr != 0) {
msc->touches[id].scroll_y_hr -= step_y_hr *
step_hr;
input_report_rel(input,
REL_WHEEL_HI_RES,
step_y_hr * SCROLL_HR_MULT);
}
break;
}
}
@ -481,6 +510,8 @@ static int magicmouse_setup_input(struct input_dev *input, struct hid_device *hd
if (emulate_scroll_wheel) {
__set_bit(REL_WHEEL, input->relbit);
__set_bit(REL_HWHEEL, input->relbit);
__set_bit(REL_WHEEL_HI_RES, input->relbit);
__set_bit(REL_HWHEEL_HI_RES, input->relbit);
}
} else if (input->id.product == USB_DEVICE_ID_APPLE_MAGICTRACKPAD2) {
/* setting the device name to ensure the same driver settings