rfcomm supports the use of ERTM

components/bt/host/bluedroid/common/include/common/bt_target.h

@@ -1565,6 +1565,31 @@
 #define PORT_CREDIT_RX_LOW          8
 #endif
 
+/* ERTM Tx window size */
+#ifndef RFC_FCR_OPT_TX_WINDOW_SIZE
+#define RFC_FCR_OPT_TX_WINDOW_SIZE  20
+#endif
+
+/* ERTM Maximum transmissions before disconnecting */
+#ifndef RFC_FCR_OPT_MAX_TX_B4_DISCNT
+#define RFC_FCR_OPT_MAX_TX_B4_DISCNT 20
+#endif
+
+/* ERTM Retransmission timeout (2 secs) */
+#ifndef RFC_FCR_OPT_RETX_TOUT
+#define RFC_FCR_OPT_RETX_TOUT        2000
+#endif
+
+/* ERTM Monitor timeout (12 secs) */
+#ifndef RFC_FCR_OPT_MONITOR_TOUT
+#define RFC_FCR_OPT_MONITOR_TOUT     12000
+#endif
+
+/* ERTM ERTM MPS segment size */
+#ifndef RFC_FCR_OPT_MAX_PDU_SIZE
+#define RFC_FCR_OPT_MAX_PDU_SIZE     1010
+#endif
+
 /******************************************************************************
 **
 ** OBEX

components/bt/host/bluedroid/stack/l2cap/l2c_utils.c

@@ -1559,7 +1559,7 @@ tL2C_CCB *l2cu_allocate_ccb (tL2C_LCB *p_lcb, UINT16 cid)
     l2c_fcr_free_timer (p_ccb);
 #endif  ///CLASSIC_BT_INCLUDED == TRUE
     p_ccb->ertm_info.preferred_mode  = L2CAP_FCR_BASIC_MODE;        /* Default mode for channel is basic mode */
-    p_ccb->ertm_info.allowed_modes   = L2CAP_FCR_CHAN_OPT_BASIC;    /* Default mode for channel is basic mode */
+    p_ccb->ertm_info.allowed_modes   = L2CAP_FCR_CHAN_OPT_BASIC|L2CAP_FCR_CHAN_OPT_BASIC;
     p_ccb->ertm_info.fcr_rx_buf_size = L2CAP_FCR_RX_BUF_SIZE;
     p_ccb->ertm_info.fcr_tx_buf_size = L2CAP_FCR_TX_BUF_SIZE;
     p_ccb->ertm_info.user_rx_buf_size = L2CAP_USER_RX_BUF_SIZE;

components/bt/host/bluedroid/stack/rfcomm/rfc_l2cap_if.c

@@ -36,6 +36,17 @@
 #include "osi/mutex.h"
 #include "osi/alarm.h"
 #if (defined RFCOMM_INCLUDED && RFCOMM_INCLUDED == TRUE)
+
+static tL2CAP_ERTM_INFO rfc_l2c_etm_opt =
+{
+    L2CAP_FCR_ERTM_MODE,
+    L2CAP_FCR_CHAN_OPT_ERTM|L2CAP_FCR_CHAN_OPT_BASIC,  /* Some devices do not support ERTM */
+    L2CAP_USER_RX_BUF_SIZE,
+    L2CAP_USER_TX_BUF_SIZE,
+    L2CAP_FCR_RX_BUF_SIZE,
+    L2CAP_FCR_TX_BUF_SIZE
+};
+
 /*
 ** Define Callback functions to be called by L2CAP
 */
@@ -117,7 +128,8 @@ void RFCOMM_ConnectInd (BD_ADDR bd_addr, UINT16 lcid, UINT16 psm, UINT8 id)
     }
 
     if (p_mcb == NULL) {
-        L2CA_ConnectRsp (bd_addr, id, lcid, L2CAP_CONN_NO_RESOURCES, 0);
+        // L2CA_ConnectRsp (bd_addr, id, lcid, L2CAP_CONN_NO_RESOURCES, 0);
+        L2CA_ErtmConnectRsp (bd_addr, id, lcid, L2CAP_CONN_NO_RESOURCES, 0, &rfc_l2c_etm_opt);
         return;
     }
     p_mcb->lcid     = lcid;
@@ -178,7 +190,9 @@ void RFCOMM_ConnectCnf (UINT16 lcid, UINT16 result)
             RFCOMM_TRACE_DEBUG ("RFCOMM_ConnectCnf peer gave up pending LCID(0x%x)", p_mcb->pending_lcid);
 
             /* Peer gave up his connection request, make sure cleaning up L2CAP channel */
-            L2CA_ConnectRsp (p_mcb->bd_addr, p_mcb->pending_id, p_mcb->pending_lcid, L2CAP_CONN_NO_RESOURCES, 0);
+            // L2CA_ConnectRsp (p_mcb->bd_addr, p_mcb->pending_id, p_mcb->pending_lcid, L2CAP_CONN_NO_RESOURCES, 0);
+            L2CA_ErtmConnectRsp (p_mcb->bd_addr, p_mcb->pending_id, p_mcb->pending_lcid, L2CAP_CONN_NO_RESOURCES, 0,
+                                    &rfc_l2c_etm_opt);
 
             p_mcb->pending_lcid = 0;
         }

components/bt/host/bluedroid/stack/rfcomm/rfc_mx_fsm.c

@@ -39,6 +39,25 @@
 #define L2CAP_SUCCESS   0
 #define L2CAP_ERROR     1
 
+static tL2CAP_ERTM_INFO rfc_l2c_etm_opt =
+{
+    L2CAP_FCR_ERTM_MODE,
+    L2CAP_FCR_CHAN_OPT_ERTM|L2CAP_FCR_CHAN_OPT_BASIC,  /* Some devices do not support ERTM */
+    L2CAP_USER_RX_BUF_SIZE,
+    L2CAP_USER_TX_BUF_SIZE,
+    L2CAP_FCR_RX_BUF_SIZE,
+    L2CAP_FCR_TX_BUF_SIZE
+};
+
+static tL2CAP_FCR_OPTS rfc_l2c_fcr_opts_def =
+{
+    L2CAP_FCR_ERTM_MODE,
+    RFC_FCR_OPT_TX_WINDOW_SIZE,     /* Tx window size */
+    RFC_FCR_OPT_MAX_TX_B4_DISCNT,   /* Maximum transmissions before disconnecting */
+    RFC_FCR_OPT_RETX_TOUT,          /* Retransmission timeout (2 secs) */
+    RFC_FCR_OPT_MONITOR_TOUT,       /* Monitor timeout (12 secs) */
+    RFC_FCR_OPT_MAX_PDU_SIZE        /* MPS segment size */
+};
 
 /********************************************************************************/
 /*              L O C A L    F U N C T I O N     P R O T O T Y P E S            */
@@ -124,7 +143,8 @@ void rfc_mx_sm_state_idle (tRFC_MCB *p_mcb, UINT16 event, void *p_data)
         /* Initialize L2CAP MTU */
         p_mcb->peer_l2cap_mtu = L2CAP_DEFAULT_MTU - RFCOMM_MIN_OFFSET - 1;
 
-        if ((p_mcb->lcid = L2CA_ConnectReq (BT_PSM_RFCOMM, p_mcb->bd_addr)) == 0) {
+        // if ((p_mcb->lcid = L2CA_ConnectReq (BT_PSM_RFCOMM, p_mcb->bd_addr)) == 0) {
+        if ((p_mcb->lcid = L2CA_ErtmConnectReq (BT_PSM_RFCOMM, p_mcb->bd_addr, &rfc_l2c_etm_opt)) == 0) {
             PORT_StartCnf (p_mcb, RFCOMM_ERROR);
             return;
         }
@@ -144,7 +164,8 @@ void rfc_mx_sm_state_idle (tRFC_MCB *p_mcb, UINT16 event, void *p_data)
     case RFC_MX_EVENT_CONN_IND:
 
         rfc_timer_start (p_mcb, RFCOMM_CONN_TIMEOUT);
-        L2CA_ConnectRsp (p_mcb->bd_addr, *((UINT8 *)p_data), p_mcb->lcid, L2CAP_CONN_OK, 0);
+        // L2CA_ConnectRsp (p_mcb->bd_addr, *((UINT8 *)p_data), p_mcb->lcid, L2CAP_CONN_OK, 0);
+        L2CA_ErtmConnectRsp (p_mcb->bd_addr, *((UINT8 *)p_data), p_mcb->lcid, L2CAP_CONN_OK, 0, &rfc_l2c_etm_opt);
 
         rfc_mx_send_config_req (p_mcb);
 
@@ -482,7 +503,8 @@ void rfc_mx_sm_state_disc_wait_ua (tRFC_MCB *p_mcb, UINT16 event, void *p_data)
 
         if (p_mcb->restart_required) {
             /* Start Request was received while disconnecting.  Execute it again */
-            if ((p_mcb->lcid = L2CA_ConnectReq (BT_PSM_RFCOMM, p_mcb->bd_addr)) == 0) {
+            // if ((p_mcb->lcid = L2CA_ConnectReq (BT_PSM_RFCOMM, p_mcb->bd_addr)) == 0) {
+            if ((p_mcb->lcid = L2CA_ErtmConnectReq (BT_PSM_RFCOMM, p_mcb->bd_addr, &rfc_l2c_etm_opt)) == 0) {
                 PORT_StartCnf (p_mcb, RFCOMM_ERROR);
                 return;
             }
@@ -554,6 +576,9 @@ static void rfc_mx_send_config_req (tRFC_MCB *p_mcb)
     cfg.mtu_present      = TRUE;
     cfg.mtu              = L2CAP_MTU_SIZE;
 
+    cfg.fcr_present = TRUE;
+    cfg.fcr = rfc_l2c_fcr_opts_def;
+
     /* Defaults set by memset
         cfg.flush_to_present = FALSE;
         cfg.qos_present      = FALSE;