1 files changed, 12 insertions, 29 deletions

diff --git a/drivers/hid/wacom_wac.c b/drivers/hid/wacom_wac.c
index c1270db12178..53235b276bb2 100644
--- a/drivers/hid/wacom_wac.c
+++ b/drivers/hid/wacom_wac.c
@@ -2571,7 +2571,14 @@ static void wacom_wac_pen_report(struct hid_device *hdev,
 				wacom_wac->hid_data.tipswitch);
 		input_report_key(input, wacom_wac->tool[0], sense);
 		if (wacom_wac->serial[0]) {
-			input_event(input, EV_MSC, MSC_SERIAL, wacom_wac->serial[0]);
+			/*
+			 * xf86-input-wacom does not accept a serial number
+			 * of '0'. Report the low 32 bits if possible, but
+			 * if they are zero, report the upper ones instead.
+			 */
+			__u32 serial_lo = wacom_wac->serial[0] & 0xFFFFFFFFu;
+			__u32 serial_hi = wacom_wac->serial[0] >> 32;
+			input_event(input, EV_MSC, MSC_SERIAL, (int)(serial_lo ? serial_lo : serial_hi));
 			input_report_abs(input, ABS_MISC, sense ? id : 0);
 		}
 
@@ -2646,8 +2653,8 @@ static void wacom_wac_finger_slot(struct wacom_wac *wacom_wac,
 {
 	struct hid_data *hid_data = &wacom_wac->hid_data;
 	bool mt = wacom_wac->features.touch_max > 1;
-	bool prox = hid_data->tipswitch &&
-		    report_touch_events(wacom_wac);
+	bool touch_down = hid_data->tipswitch && hid_data->confidence;
+	bool prox = touch_down && report_touch_events(wacom_wac);
 
 	if (touch_is_muted(wacom_wac)) {
 		if (!wacom_wac->shared->touch_down)
@@ -2697,24 +2704,6 @@ static void wacom_wac_finger_slot(struct wacom_wac *wacom_wac,
 	}
 }
 
-static bool wacom_wac_slot_is_active(struct input_dev *dev, int key)
-{
-	struct input_mt *mt = dev->mt;
-	struct input_mt_slot *s;
-
-	if (!mt)
-		return false;
-
-	for (s = mt->slots; s != mt->slots + mt->num_slots; s++) {
-		if (s->key == key &&
-			input_mt_get_value(s, ABS_MT_TRACKING_ID) >= 0) {
-			return true;
-		}
-	}
-
-	return false;
-}
-
 static void wacom_wac_finger_event(struct hid_device *hdev,
 		struct hid_field *field, struct hid_usage *usage, __s32 value)
 {
@@ -2765,14 +2754,8 @@ static void wacom_wac_finger_event(struct hid_device *hdev,
 	}
 
 	if (usage->usage_index + 1 == field->report_count) {
-		if (equivalent_usage == wacom_wac->hid_data.last_slot_field) {
-			bool touch_removed = wacom_wac_slot_is_active(wacom_wac->touch_input,
-				wacom_wac->hid_data.id) && !wacom_wac->hid_data.tipswitch;
-
-			if (wacom_wac->hid_data.confidence || touch_removed) {
-				wacom_wac_finger_slot(wacom_wac, wacom_wac->touch_input);
-			}
-		}
+		if (equivalent_usage == wacom_wac->hid_data.last_slot_field)
+			wacom_wac_finger_slot(wacom_wac, wacom_wac->touch_input);
 	}
 }