diff --git a/src/bts.h b/src/bts.h
index aaf81cfa..a32e87db 100644
--- a/src/bts.h
+++ b/src/bts.h
@@ -163,8 +163,6 @@ struct gprs_rlcmac_trx {
 extern "C" {
 #endif
 void bts_update_tbf_ta(const char *p, uint32_t fn, uint8_t trx_no, uint8_t ts, int8_t ta, bool is_rach);
-void update_tbf_ta(struct gprs_rlcmac_ul_tbf *tbf, int8_t ta_delta);
-void set_tbf_ta(struct gprs_rlcmac_ul_tbf *tbf, uint8_t ta);
 #ifdef __cplusplus
 }
 #endif
diff --git a/src/tbf.h b/src/tbf.h
index 95e1e892..e9d8df8e 100644
--- a/src/tbf.h
+++ b/src/tbf.h
@@ -562,6 +562,15 @@ protected:
 	void maybe_schedule_uplink_acknack(const gprs_rlc_data_info *rlc);
 };
 
+#ifdef __cplusplus
+extern "C" {
+#endif
+void update_tbf_ta(struct gprs_rlcmac_ul_tbf *tbf, int8_t ta_delta);
+void set_tbf_ta(struct gprs_rlcmac_ul_tbf *tbf, uint8_t ta);
+#ifdef __cplusplus
+}
+#endif
+
 inline enum gprs_rlcmac_tbf_direction reverse(enum gprs_rlcmac_tbf_direction dir)
 {
 	return (enum gprs_rlcmac_tbf_direction)