diff --git a/src/tbf_fsm.h b/src/tbf_fsm.h
index 8f4f839..feb9e04 100644
--- a/src/tbf_fsm.h
+++ b/src/tbf_fsm.h
@@ -23,36 +23,50 @@
 struct gprs_rlcmac_tbf;
 
 enum tbf_fsm_event {
-	TBF_EV_ASSIGN_ADD_CCCH, /* An assignment is sent over CCCH and confirmation from MS is pending */
+	/* For both UL/DL TBF: */
+	TBF_EV_ASSIGN_ADD_CCCH,  /* An assignment is sent over CCCH and confirmation from MS is pending */
 	TBF_EV_ASSIGN_ADD_PACCH, /* An assignment is sent over PACCH and confirmation from MS is pending */
-	TBF_EV_ASSIGN_ACK_PACCH, /*  We received a CTRL ACK confirming assignment started on PACCH */
+	TBF_EV_ASSIGN_ACK_PACCH, /* We received a CTRL ACK confirming assignment started on PACCH */
+	TBF_EV_MAX_N3105, /* MAX N3105 (max poll timeout) reached */
+
+	/* Only for DL TBF: */
 	TBF_EV_ASSIGN_READY_CCCH, /* TBF Start Time timer triggered */
-	TBF_EV_ASSIGN_PCUIF_CNF, /* Transmission of IMM.ASS for DL TBF to the MS confirmed by BTS over PCUIF */
-	TBF_EV_FIRST_UL_DATA_RECVD, /* UL TBF: Received first UL data from MS. Equals to Contention Resolution completed on the network side */
-	TBF_EV_CONTENTION_RESOLUTION_MS_SUCCESS, /* UL TBF: Contention resolution success at the mobile station side (first UL_ACK_NACK confirming TLLI is received at the MS) */
-	TBF_EV_DL_ACKNACK_MISS, /* DL TBF: We polled for DL ACK/NACK but we received none (POLL timeout) */
-	TBF_EV_LAST_DL_DATA_SENT, /* DL TBF sends RLCMAC block containing last DL avilable data buffered */
-	TBF_EV_LAST_UL_DATA_RECVD, /* UL TBF sends RLCMAC block containing last UL data (cv=0) */
+	TBF_EV_ASSIGN_PCUIF_CNF, /* Transmission of IMM.ASS for to the MS confirmed by BTS over PCUIF */
+	TBF_EV_DL_ACKNACK_MISS, /* We polled for DL ACK/NACK but we received none (POLL timeout) */
+	TBF_EV_LAST_DL_DATA_SENT, /* Network sends RLCMAC block containing last DL avilable data buffered */
 	TBF_EV_FINAL_ACK_RECVD, /* DL ACK/NACK with FINAL_ACK=1 received from MS */
-	TBF_EV_FINAL_UL_ACK_CONFIRMED, /* UL TBF: MS ACKs (CtrlAck or PktResReq) our UL ACK/NACK w/ FinalAckInd=1. data = (bool) MS requests establishment of a new UL-TBF. */
-	TBF_EV_MAX_N3101, /* MAX N3101 (max usf timeout) reached (UL TBF) */
-	TBF_EV_MAX_N3103, /* MAX N3103 (max Pkt Ctrl Ack for last UL ACK/NACK timeout) reached (UL TBF) */
-	TBF_EV_MAX_N3105, /* MAX N3105 (max poll timeout) reached (UL/DL TBF) */
+
+	/* Only for UL TBF: */
+	TBF_EV_FIRST_UL_DATA_RECVD, /* Received first UL data from MS. Equals to Contention Resolution completed on the network side */
+	TBF_EV_CONTENTION_RESOLUTION_MS_SUCCESS, /* Contention resolution success at the mobile station side (first UL_ACK_NACK confirming TLLI is received at the MS) */
+	TBF_EV_LAST_UL_DATA_RECVD, /* MS ends RLCMAC block containing last UL data (cv=0) */
+	TBF_EV_FINAL_UL_ACK_CONFIRMED, /* MS ACKs (CtrlAck or PktResReq) our UL ACK/NACK w/ FinalAckInd=1. data = (bool) MS requests establishment of a new UL-TBF. */
+	TBF_EV_MAX_N3101, /* MAX N3101 (max usf timeout) reached */
+	TBF_EV_MAX_N3103, /* MAX N3103 (max Pkt Ctrl Ack for last UL ACK/NACK timeout) reached */
 };
 
+extern const struct value_string tbf_fsm_event_names[];
+
 enum tbf_fsm_states {
 	TBF_ST_NEW = 0,	/* new created TBF */
 	TBF_ST_ASSIGN,	/* wait for downlink assignment */
 	TBF_ST_FLOW,	/* RLC/MAC flow, resource needed */
 	TBF_ST_FINISHED,	/* flow finished, wait for release */
-	TBF_ST_WAIT_RELEASE,/* wait for release or restart of DL TBF */
+	TBF_ST_WAIT_RELEASE,/* DL TBF: wait for release or restart */
 	TBF_ST_RELEASING,	/* releasing, wait to free TBI/USF */
 };
 
-struct tbf_fsm_ctx {
-	struct gprs_rlcmac_tbf* tbf; /* back pointer */
+struct tbf_dl_fsm_ctx {
+	struct gprs_rlcmac_tbf *tbf; /* back pointer */
 	uint32_t state_flags;
 	unsigned int T_release; /* Timer to be used to end release: T3169 or T3195 */
 };
 
-extern struct osmo_fsm tbf_fsm;
+struct tbf_ul_fsm_ctx {
+	struct gprs_rlcmac_tbf *tbf; /* back pointer */
+	uint32_t state_flags;
+	unsigned int T_release; /* Timer to be used to end release: T3169 or T3195 */
+};
+
+extern struct osmo_fsm tbf_dl_fsm;
+extern struct osmo_fsm tbf_ul_fsm;