bna: Add RX State

Change Details:
 -      BNA state machine for Rx in start_wait state moves it to stop_wait on
        receipt of RX_E_STOP. In Rx stop_wait state, on receipt of
                RX_E_STARTED event does enet stop
                RX_E_STOPPED event does rx_cleanup_cbfn
        rx_cleanup_cbfn in this case is called without post_cbfn. post_cbfn
        happens only after RX_E_STARTED event is received in start_wait. Without
        doing post_cbfn, NAPI remains disabled and in cleanup we try to disable
        again causing endless wait. ifconfig process and other workers can thus
        get stuck.
 -      Introducing start_stop_wait state for Rx. This state handles the case of
        if post_cbfn is not done simply do stop without the cleanup.
Signed-off-by: Rasesh Mody <rmody@brocade.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

drivers/net/ethernet/brocade/bna/bna_tx_rx.c

@@ -1355,6 +1355,8 @@ bfa_fsm_state_decl(bna_rx, stopped,
 	struct bna_rx, enum bna_rx_event);
 bfa_fsm_state_decl(bna_rx, start_wait,
 	struct bna_rx, enum bna_rx_event);
+bfa_fsm_state_decl(bna_rx, start_stop_wait,
+	struct bna_rx, enum bna_rx_event);
 bfa_fsm_state_decl(bna_rx, rxf_start_wait,
 	struct bna_rx, enum bna_rx_event);
 bfa_fsm_state_decl(bna_rx, started,
@@ -1432,7 +1434,7 @@ static void bna_rx_sm_start_wait(struct bna_rx *rx,
 {
 	switch (event) {
 	case RX_E_STOP:
-		bfa_fsm_set_state(rx, bna_rx_sm_stop_wait);
+		bfa_fsm_set_state(rx, bna_rx_sm_start_stop_wait);
 		break;
 
 	case RX_E_FAIL:
@@ -1488,6 +1490,29 @@ bna_rx_sm_rxf_stop_wait(struct bna_rx *rx, enum bna_rx_event event)
 
 }
 
+static void
+bna_rx_sm_start_stop_wait_entry(struct bna_rx *rx)
+{
+}
+
+static void
+bna_rx_sm_start_stop_wait(struct bna_rx *rx, enum bna_rx_event event)
+{
+	switch (event) {
+	case RX_E_FAIL:
+	case RX_E_STOPPED:
+		bfa_fsm_set_state(rx, bna_rx_sm_stopped);
+		break;
+
+	case RX_E_STARTED:
+		bna_rx_enet_stop(rx);
+		break;
+
+	default:
+		bfa_sm_fault(event);
+	}
+}
+
 void
 bna_rx_sm_started_entry(struct bna_rx *rx)
 {