File xf86-input-synaptics-move-threshold.diff of Package xorg-x11-driver-input

---
 src/synaptics.c    |   11 +++++++++++
 src/synapticsstr.h |    1 +
 2 files changed, 12 insertions(+)

--- a/src/synaptics.c
+++ b/src/synaptics.c
@@ -441,6 +441,8 @@
     edgeMotionMaxSpeed = diag * .080;
     accelFactor = 200.0 / diag; /* trial-and-error */
 
+    priv->move_ptr_threshold = width / 5;
+
     /* hysteresis, assume >= 0 is a detected value (e.g. evdev fuzz) */
     horizHyst = pars->hyst_x >= 0 ? pars->hyst_x : diag * 0.005;
     vertHyst = pars->hyst_y >= 0 ? pars->hyst_y : diag * 0.005;
@@ -2042,6 +2044,15 @@
 	}
     }
 
+    if (moving_state && priv->count_packet_finger > 0 &&
+	priv->move_ptr_threshold > 0 ) {
+	int d = move_distance(HIST(0).x - hw->x, HIST(0).y - hw->y);
+	if (d > priv->move_ptr_threshold) {
+	    priv->count_packet_finger = 0; /* to avoid unexpected jumps */
+	    goto out;
+	}
+    }
+
     if (!inside_area || !moving_state || priv->palm ||
 	priv->vert_scroll_edge_on || priv->horiz_scroll_edge_on ||
 	priv->vert_scroll_twofinger_on || priv->horiz_scroll_twofinger_on ||
--- a/src/synapticsstr.h
+++ b/src/synapticsstr.h
@@ -254,6 +254,7 @@
     unsigned int clickpad_threshold;
     int clickpad_dx, clickpad_dy;
     struct SynapticsHwState prev_hw;	/* previous h/w state (for clickpad) */
+    int move_ptr_threshold;
     int prop_change_pending;
     Bool led_touch_state;
     Bool led_tapped;