diff --git a/include/openbsc/gsm_data.h b/include/openbsc/gsm_data.h
index 8bb219a..75de2e7 100644
--- a/include/openbsc/gsm_data.h
+++ b/include/openbsc/gsm_data.h
@@ -126,5 +126,13 @@
 	/* the 'local' subscriber */
 	struct gsm_subscriber *subscr;
 };
-	
+
+enum gsm_e1_event {
+	EVT_E1_NONE,
+	EVT_E1_OML_UP,
+	EVT_E1_RSL_UP,
+	EVT_E1_OML_DN,
+	EVT_E1_RSL_DN,
+};
+
 #endif