touchpad: improve trackpoint palm detection responsiveness

The touchpad is disabled for 500ms after a trackpoint event to avoid
erroneous palm touches. This is currently refreshed on every trackpoint event
and thus forces a delay of 500ms when switching between the two.

Instead, reduce the timeout to 300ms but ignore any touches started while the
trackpoint was active (i.e. before the last trackpoint event). A touch started
after the last event is released once the timeout expires.

This is the same logic used for disable-while-typing.

https://bugzilla.redhat.com/show_bug.cgi?id=1233844

Signed-off-by: Peter Hutterer <peter.hutterer@who-t.net>
Reviewed-by: Hans de Goede <hdegoede@redhat.com>

diff --git a/src/evdev-mt-touchpad.c b/src/evdev-mt-touchpad.c
index 792184c..538c2d7 100644 (file)
--- a/src/evdev-mt-touchpad.c
+++ b/src/evdev-mt-touchpad.c
@@ -34,7 +34,7 @@
  * TP_MAGIC_SLOWDOWN in filter.c */
 #define DEFAULT_ACCEL_NUMERATOR 3000.0
 #define DEFAULT_HYSTERESIS_MARGIN_DENOMINATOR 700.0
-#define DEFAULT_TRACKPOINT_ACTIVITY_TIMEOUT 500 /* ms */
+#define DEFAULT_TRACKPOINT_ACTIVITY_TIMEOUT 300 /* ms */
 #define DEFAULT_KEYBOARD_ACTIVITY_TIMEOUT_1 200 /* ms */
 #define DEFAULT_KEYBOARD_ACTIVITY_TIMEOUT_2 500 /* ms */
 #define FAKE_FINGER_OVERFLOW (1 << 7)
@@ -515,6 +515,31 @@ tp_palm_detect_dwt(struct tp_dispatch *tp, struct tp_touch *t, uint64_t time)
        return 0;
 }
 
+static int
+tp_palm_detect_trackpoint(struct tp_dispatch *tp,
+                         struct tp_touch *t,
+                         uint64_t time)
+{
+       if (t->palm.state == PALM_NONE &&
+           t->state == TOUCH_BEGIN &&
+           tp->palm.trackpoint_active) {
+               t->palm.state = PALM_TRACKPOINT;
+               return 1;
+       } else if (t->palm.state == PALM_TRACKPOINT &&
+                  t->state == TOUCH_UPDATE &&
+                  !tp->palm.trackpoint_active) {
+
+               if (t->palm.time == 0 ||
+                   t->palm.time > tp->palm.trackpoint_last_event_time) {
+                       t->palm.state = PALM_NONE;
+                       log_debug(tp_libinput_context(tp),
+                                 "palm: touch released, timeout after trackpoint\n");
+               }
+       }
+
+       return 0;
+}
+
 static void
 tp_palm_detect(struct tp_dispatch *tp, struct tp_touch *t, uint64_t time)
 {
@@ -526,6 +551,9 @@ tp_palm_detect(struct tp_dispatch *tp, struct tp_touch *t, uint64_t time)
        if (tp_palm_detect_dwt(tp, t, time))
                goto out;
 
+       if (tp_palm_detect_trackpoint(tp, t, time))
+               goto out;
+
        /* If labelled a touch as palm, we unlabel as palm when
           we move out of the palm edge zone within the timeout, provided
           the direction is within 45 degrees of the horizontal.
@@ -568,7 +596,8 @@ tp_palm_detect(struct tp_dispatch *tp, struct tp_touch *t, uint64_t time)
 out:
        log_debug(tp_libinput_context(tp),
                  "palm: palm detected (%s)\n",
-                 t->palm.state == PALM_EDGE ? "edge" : "typing");
+                 t->palm.state == PALM_EDGE ? "edge" :
+                 t->palm.state == PALM_TYPING ? "typing" : "trackpoint");
 }
 
 static void
@@ -948,6 +977,7 @@ tp_trackpoint_event(uint64_t time, struct libinput_event *event, void *data)
                tp->palm.trackpoint_active = true;
        }
 
+       tp->palm.trackpoint_last_event_time = time;
        libinput_timer_set(&tp->palm.trackpoint_timer,
                           time + DEFAULT_TRACKPOINT_ACTIVITY_TIMEOUT);
 }

diff --git a/src/evdev-mt-touchpad.h b/src/evdev-mt-touchpad.h
index d4a57a8..f3c2bf7 100644 (file)
--- a/src/evdev-mt-touchpad.h
+++ b/src/evdev-mt-touchpad.h
@@ -64,6 +64,7 @@ enum touch_palm_state {
        PALM_NONE = 0,
        PALM_EDGE,
        PALM_TYPING,
+       PALM_TRACKPOINT,
 };
 
 enum button_event {
@@ -281,6 +282,7 @@ struct tp_dispatch {
                bool trackpoint_active;
                struct libinput_event_listener trackpoint_listener;
                struct libinput_timer trackpoint_timer;
+               uint64_t trackpoint_last_event_time;
        } palm;
 
        struct {