diff --git a/include/openbsc/gsm_data.h b/include/openbsc/gsm_data.h
index 0e3a380..071b1c6 100644
--- a/include/openbsc/gsm_data.h
+++ b/include/openbsc/gsm_data.h
@@ -138,8 +138,10 @@
 	struct gsm_bts_trx_ts *ts;
 	/* The logical subslot number in the TS */
 	u_int8_t nr;
-	/* The lotical channel type */
+	/* The logical channel type */
 	enum gsm_chan_t type;
+	/* If TCH, traffic channel mode */
+	enum gsm_chan_t tch_mode;
 	/* Power levels for MS and BTS */
 	u_int8_t bs_power;
 	u_int8_t ms_power;
diff --git a/include/openbsc/trau_mux.h b/include/openbsc/trau_mux.h
index f3d519f..90535ad 100644
--- a/include/openbsc/trau_mux.h
+++ b/include/openbsc/trau_mux.h
@@ -36,8 +36,14 @@
 			const struct gsm_lchan *dst);
 
 /* unmap a TRAU mux map entry */
-int trau_mux_unmap(const struct gsm_e1_subslot *ss);
+int trau_mux_unmap(const struct gsm_e1_subslot *ss, u_int32_t callref);
 
 /* we get called by subchan_demux */
 int trau_mux_input(struct gsm_e1_subslot *src_e1_ss,
 		   const u_int8_t *trau_bits, int num_bits);
+
+/* add a trau receiver */
+int trau_recv_lchan(struct gsm_lchan *lchan, u_int32_t callref);
+
+/* send trau from application */
+int trau_send_lchan(struct gsm_lchan *lchan, struct decoded_trau_frame *tf);