Bluetooth: RFCOMM: Implement timer in session

As per the spec, the station which disconnects the last dlc should disconnect session also. In case if remote does not do it we need to disconnect otherwise rfcomm will be connected without any dlc. So this starts an idle timer to handle the above scenario. This also starts a disconnect timer to handle in case remote does not respond to session disconnect request. Change-Id: I3b45aa5bf4c35fd81dc10974f2b0b6d4cfe4ea7d Signed-off-by: Jaganath Kanakkassery <[email protected]>
k0d · Jan 5, 2017 · c37b59b · c37b59b
1 parent b5891d1
commit c37b59b
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Showing 2 changed files with 47 additions and 0 deletions.
diff --git a/subsys/bluetooth/host/rfcomm.c b/subsys/bluetooth/host/rfcomm.c
@@ -54,9 +54,12 @@
 
 #define RFCOMM_CONN_TIMEOUT     K_SECONDS(60)
 #define RFCOMM_DISC_TIMEOUT     K_SECONDS(20)
+#define RFCOMM_IDLE_TIMEOUT     K_SECONDS(2)
 
 #define DLC_RTX(_w) CONTAINER_OF(_w, struct bt_rfcomm_dlc, rtx_work)
 
+#define SESSION_RTX(_w) CONTAINER_OF(_w, struct bt_rfcomm_session, rtx_work)
+
 static struct bt_rfcomm_server *servers;
 
 /* Pool for outgoing RFCOMM control packets, min MTU is 23 */
@@ -248,6 +251,14 @@ static void rfcomm_dlc_destroy(struct bt_rfcomm_dlc *dlc)
 {
 	BT_DBG("dlc %p", dlc);
 
+	if (!dlc->session->dlcs) {
+		/* Start an idle timer. Incase we initiate session disconnect
+		 * then this will be restarted as DISC timer
+		 */
+		k_delayed_work_submit(&dlc->session->rtx_work,
+				      RFCOMM_IDLE_TIMEOUT);
+	}
+
 	k_delayed_work_cancel(&dlc->rtx_work);
 	dlc->state = BT_RFCOMM_STATE_IDLE;
 	dlc->session = NULL;
@@ -375,6 +386,7 @@ static void rfcomm_session_disconnect(struct bt_rfcomm_session *session)
 
 	session->state = BT_RFCOMM_STATE_DISCONNECTING;
 	rfcomm_send_disc(session, 0);
+	k_delayed_work_submit(&session->rtx_work, RFCOMM_DISC_TIMEOUT);
 }
 
 static struct net_buf *rfcomm_make_uih_msg(struct bt_rfcomm_session *session,
@@ -423,6 +435,7 @@ static void rfcomm_disconnected(struct bt_l2cap_chan *chan)
 
 	BT_DBG("Session %p", session);
 
+	k_delayed_work_cancel(&session->rtx_work);
 	rfcomm_session_disconnected(session);
 	session->state = BT_RFCOMM_STATE_IDLE;
 }
@@ -826,6 +839,9 @@ static void rfcomm_handle_sabm(struct bt_rfcomm_session *session, uint8_t dlci)
 			return;
 		}
 
+		/* Cancel idle timer if any */
+		k_delayed_work_cancel(&session->rtx_work);
+
 		rfcomm_dlc_connected(dlc);
 	}
 }
@@ -931,6 +947,8 @@ static void rfcomm_handle_ua(struct bt_rfcomm_session *session, uint8_t dlci)
 			break;
 		case BT_RFCOMM_STATE_DISCONNECTING:
 			session->state = BT_RFCOMM_STATE_DISCONNECTED;
+			/* Cancel disc timer */
+			k_delayed_work_cancel(&session->rtx_work);
 			err = bt_l2cap_chan_disconnect(&session->br_chan.chan);
 			if (err < 0) {
 				session->state = BT_RFCOMM_STATE_IDLE;
@@ -1093,6 +1111,8 @@ static void rfcomm_handle_pn(struct bt_rfcomm_session *session,
 		rfcomm_dlc_tx_give_credits(dlc, pn->credits);
 		dlc->state = BT_RFCOMM_STATE_CONFIG;
 		rfcomm_send_pn(dlc, BT_RFCOMM_MSG_RESP_CR);
+		/* Cancel idle timer if any */
+		k_delayed_work_cancel(&session->rtx_work);
 	} else {
 		/* If its a command */
 		if (cr) {
@@ -1132,6 +1152,8 @@ static void rfcomm_handle_disc(struct bt_rfcomm_session *session, uint8_t dlci)
 		rfcomm_send_ua(session, dlci);
 		rfcomm_dlc_disconnect(dlc);
 	} else {
+		/* Cancel idle timer */
+		k_delayed_work_cancel(&session->rtx_work);
 		rfcomm_send_ua(session, 0);
 		rfcomm_session_disconnected(session);
 	}
@@ -1377,6 +1399,25 @@ static void rfcomm_encrypt_change(struct bt_l2cap_chan *chan,
 	}
 }
 
+static void rfcomm_session_rtx_timeout(struct k_work *work)
+{
+	struct bt_rfcomm_session *session = SESSION_RTX(work);
+
+	BT_WARN("session %p state %d timeout", session, session->state);
+
+	switch (session->state) {
+	case BT_RFCOMM_STATE_CONNECTED:
+		rfcomm_session_disconnect(session);
+		break;
+	case BT_RFCOMM_STATE_DISCONNECTING:
+		session->state = BT_RFCOMM_STATE_DISCONNECTED;
+		if (bt_l2cap_chan_disconnect(&session->br_chan.chan) < 0) {
+			session->state = BT_RFCOMM_STATE_IDLE;
+		}
+		break;
+	}
+}
+
 static struct bt_rfcomm_session *rfcomm_session_new(bt_rfcomm_role_t role)
 {
 	int i;
@@ -1400,6 +1441,8 @@ static struct bt_rfcomm_session *rfcomm_session_new(bt_rfcomm_role_t role)
 		session->br_chan.rx.mtu	= CONFIG_BLUETOOTH_RFCOMM_L2CAP_MTU;
 		session->state = BT_RFCOMM_STATE_INIT;
 		session->role = role;
+		k_delayed_work_init(&session->rtx_work,
+				    rfcomm_session_rtx_timeout);
 
 		return session;
 	}
@@ -1471,6 +1514,8 @@ int bt_rfcomm_dlc_connect(struct bt_conn *conn, struct bt_rfcomm_dlc *dlc,
 		if (ret < 0) {
 			goto fail;
 		}
+		/* Cancel idle timer if any */
+		k_delayed_work_cancel(&session->rtx_work);
 		break;
 	default:
 		BT_ERR("Invalid session state %d", session->state);

diff --git a/subsys/bluetooth/host/rfcomm_internal.h b/subsys/bluetooth/host/rfcomm_internal.h
@@ -24,6 +24,8 @@
 struct bt_rfcomm_session {
 	/* L2CAP channel this context is associated with */
 	struct bt_l2cap_br_chan br_chan;
+	/* Response Timeout eXpired (RTX) timer */
+	struct k_delayed_work rtx_work;
 	struct bt_rfcomm_dlc *dlcs;
 	uint16_t mtu;
 	uint8_t state;