v4.19.13 snapshot.
diff --git a/drivers/input/mouse/logips2pp.h b/drivers/input/mouse/logips2pp.h
new file mode 100644
index 0000000..bf62945
--- /dev/null
+++ b/drivers/input/mouse/logips2pp.h
@@ -0,0 +1,23 @@
+/*
+ * Logitech PS/2++ mouse driver header
+ *
+ * Copyright (c) 2003 Vojtech Pavlik <vojtech@suse.cz>
+ *
+ * This program is free software; you can redistribute it and/or modify it
+ * under the terms of the GNU General Public License version 2 as published by
+ * the Free Software Foundation.
+ */
+
+#ifndef _LOGIPS2PP_H
+#define _LOGIPS2PP_H
+
+#ifdef CONFIG_MOUSE_PS2_LOGIPS2PP
+int ps2pp_detect(struct psmouse *psmouse, bool set_properties);
+#else
+static inline int ps2pp_detect(struct psmouse *psmouse, bool set_properties)
+{
+ return -ENOSYS;
+}
+#endif /* CONFIG_MOUSE_PS2_LOGIPS2PP */
+
+#endif