touchpad: add MT_TOOL-based palm detection

If the touchpad driver tells us something is a palm, go with that.

https://bugs.freedesktop.org/show_bug.cgi?id=100243

Signed-off-by: Peter Hutterer <peter.hutterer@who-t.net>

2 files changed, 45 insertions, 0 deletions

diff --git a/src/evdev-mt-touchpad.c b/src/evdev-mt-touchpad.c
index f41dd68..8585351 100644
--- a/src/evdev-mt-touchpad.c
+++ b/src/evdev-mt-touchpad.c
@@ -341,6 +341,11 @@ tp_process_absolute(struct tp_dispatch *tp,
 		t->dirty = true;
 		tp->queued |= TOUCHPAD_EVENT_OTHERAXIS;
 		break;
+	case ABS_MT_TOOL_TYPE:
+		t->is_tool_palm = e->value == MT_TOOL_PALM;
+		t->dirty = true;
+		tp->queued |= TOUCHPAD_EVENT_OTHERAXIS;
+		break;
 	}
 }
 
@@ -622,6 +627,31 @@ tp_palm_detect_trackpoint_triggered(struct tp_dispatch *tp,
 	return false;
 }
 
+static bool
+tp_palm_detect_tool_triggered(struct tp_dispatch *tp,
+			      struct tp_touch *t,
+			      uint64_t time)
+{
+	if (!tp->palm.use_mt_tool)
+		return false;
+
+	if (t->palm.state != PALM_NONE &&
+	    t->palm.state != PALM_TOOL_PALM)
+		return false;
+
+	if (t->palm.state == PALM_NONE &&
+	    t->is_tool_palm)
+		t->palm.state = PALM_TOOL_PALM;
+	else if (t->palm.state == PALM_TOOL_PALM &&
+		 !t->is_tool_palm)
+		t->palm.state = PALM_NONE;
+
+	if (t->palm.state == PALM_TOOL_PALM)
+		tp_stop_actions(tp, time);
+
+	return t->palm.state == PALM_TOOL_PALM;
+}
+
 static inline bool
 tp_palm_detect_move_out_of_edge(struct tp_dispatch *tp,
 				struct tp_touch *t,
@@ -732,6 +762,9 @@ tp_palm_detect(struct tp_dispatch *tp, struct tp_touch *t, uint64_t time)
 	if (tp_palm_detect_trackpoint_triggered(tp, t, time))
 		goto out;
 
+	if (tp_palm_detect_tool_triggered(tp, t, time))
+		goto out;
+
 	if (tp_palm_detect_edge(tp, t, time))
 		goto out;
 
@@ -750,6 +783,9 @@ out:
 	case PALM_TRACKPOINT:
 		palm_state = "trackpoint";
 		break;
+	case PALM_TOOL_PALM:
+		palm_state = "tool-palm";
+		break;
 	case PALM_NONE:
 	default:
 		abort();
@@ -2267,6 +2303,11 @@ tp_init_palmdetect(struct tp_dispatch *tp,
 
 	tp->palm.monitor_trackpoint = true;
 
+	if (libevdev_has_event_code(device->evdev,
+				    EV_ABS,
+				    ABS_MT_TOOL_TYPE))
+		tp->palm.use_mt_tool = true;
+
 	tp_init_palmdetect_edge(tp, device);
 }
 
diff --git a/src/evdev-mt-touchpad.h b/src/evdev-mt-touchpad.h
index 2d531b5..93dd37b 100644
--- a/src/evdev-mt-touchpad.h
+++ b/src/evdev-mt-touchpad.h
@@ -66,6 +66,7 @@ enum touch_palm_state {
 	PALM_EDGE,
 	PALM_TYPING,
 	PALM_TRACKPOINT,
+	PALM_TOOL_PALM,
 };
 
 enum button_event {
@@ -154,6 +155,7 @@ struct tp_touch {
 	struct device_coords point;
 	uint64_t millis;
 	int pressure;
+	bool is_tool_palm; /* MT_TOOL_PALM */
 
 	bool was_down; /* if distance == 0, false for pure hovering
 			  touches */
@@ -347,6 +349,8 @@ struct tp_dispatch {
 		uint64_t trackpoint_last_event_time;
 		uint32_t trackpoint_event_count;
 		bool monitor_trackpoint;
+
+		bool use_mt_tool;
 	} palm;
 
 	struct {