1 files changed, 35 insertions, 4 deletions

diff --git a/drivers/hid/wacom_wac.c b/drivers/hid/wacom_wac.c
index e011839f19f8..de69ea5f5a4b 100644
--- a/drivers/hid/wacom_wac.c
+++ b/drivers/hid/wacom_wac.c
@@ -2566,6 +2566,24 @@ 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)
 {
@@ -2613,9 +2631,14 @@ 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 &&
-		    wacom_wac->hid_data.confidence)
-			wacom_wac_finger_slot(wacom_wac, wacom_wac->touch_input);
+		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);
+			}
+		}
 	}
 }
 
@@ -2631,6 +2654,10 @@ static void wacom_wac_finger_pre_report(struct hid_device *hdev,
 
 	hid_data->confidence = true;
 
+	hid_data->cc_report = 0;
+	hid_data->cc_index = -1;
+	hid_data->cc_value_index = -1;
+
 	for (i = 0; i < report->maxfield; i++) {
 		struct hid_field *field = report->field[i];
 		int j;
@@ -2664,11 +2691,14 @@ static void wacom_wac_finger_pre_report(struct hid_device *hdev,
 	    hid_data->cc_index >= 0) {
 		struct hid_field *field = report->field[hid_data->cc_index];
 		int value = field->value[hid_data->cc_value_index];
-		if (value)
+		if (value) {
 			hid_data->num_expected = value;
+			hid_data->num_received = 0;
+		}
 	}
 	else {
 		hid_data->num_expected = wacom_wac->features.touch_max;
+		hid_data->num_received = 0;
 	}
 }
 
@@ -2692,6 +2722,7 @@ static void wacom_wac_finger_report(struct hid_device *hdev,
 
 	input_sync(input);
 	wacom_wac->hid_data.num_received = 0;
+	wacom_wac->hid_data.num_expected = 0;
 
 	/* keep touch state for pen event */
 	wacom_wac->shared->touch_down = wacom_wac_finger_count_touches(wacom_wac);