HID: 3m: Adjust major / minor axes to scale

By visual inspection, the reported touch_major and touch_minor axes
are a factor of two too large. Presumably the device actually reports
the width_major and width_minor, which are generally about a factor of
two larger than the touches themselves.
Signed-off-by: Henrik Rydberg <rydberg@euromail.se>
Signed-off-by: Jiri Kosina <jkosina@suse.cz>

drivers/hid/hid-3m-pct.c

@@ -166,16 +166,18 @@ static void mmm_filter_event(struct mmm_data *md, struct input_dev *input)
 		if (f->touch) {
 			/* this finger is on the screen */
 			int wide = (f->w > f->h);
+			/* divided by two to match visual scale of touch */
+			int major = max(f->w, f->h) >> 1;
+			int minor = min(f->w, f->h) >> 1;
+
 			if (!f->prev_touch)
 				f->id = md->id++;
 			input_event(input, EV_ABS, ABS_MT_TRACKING_ID, f->id);
 			input_event(input, EV_ABS, ABS_MT_POSITION_X, f->x);
 			input_event(input, EV_ABS, ABS_MT_POSITION_Y, f->y);
 			input_event(input, EV_ABS, ABS_MT_ORIENTATION, wide);
-			input_event(input, EV_ABS, ABS_MT_TOUCH_MAJOR,
-						wide ? f->w : f->h);
-			input_event(input, EV_ABS, ABS_MT_TOUCH_MINOR,
-						wide ? f->h : f->w);
+			input_event(input, EV_ABS, ABS_MT_TOUCH_MAJOR, major);
+			input_event(input, EV_ABS, ABS_MT_TOUCH_MINOR, minor);
 			/* touchscreen emulation: pick the oldest contact */
 			if (!oldest || ((f->id - oldest->id) & (SHRT_MAX + 1)))
 				oldest = f;