diff --git a/openbsc/src/gsm_data.c b/openbsc/src/gsm_data.c
index 446a820..d2676db 100644
--- a/openbsc/src/gsm_data.c
+++ b/openbsc/src/gsm_data.c
@@ -365,6 +365,17 @@
 	return bts_types[type];
 }
 
+struct gsm_bts_trx *gsm_bts_trx_by_nr(struct gsm_bts *bts, int nr)
+{
+	struct gsm_bts_trx *trx;
+
+	llist_for_each_entry(trx, &bts->trx_list, list) {
+		if (trx->nr == nr)
+			return trx;
+	}
+	return NULL;
+}
+
 /* Search for a BTS in the given Location Area; optionally start searching
  * with start_bts (for continuing to search after the first result) */
 struct gsm_bts *gsm_bts_by_lac(struct gsm_network *net, unsigned int lac,