Wait until RUs are ready and add <disconnect> RPC for M-plane

- if RU(s) are not well configured, disconnect immediately and stop the DU
  - if all RUs are well configured, proceed with waiting until ready. The RU is
    ready when the carriers are activated. Either the RU already has preconfigured
    carriers (previous M-plane client configured), or the DU has to wait until receives
    the notifications.

radio/fhi_72/mplane/connect-mplane.c

@@ -55,3 +55,19 @@ bool connect_mplane(ru_session_t *ru_session)
 
   return true;
 }
+
+void disconnect_mplane(void *rus_disconnect)
+{
+  ru_session_list_t *ru_session_list = (ru_session_list_t *)rus_disconnect;
+
+  for (size_t i = 0; i <ru_session_list->num_rus; i++) {
+    ru_session_t *ru_session = &ru_session_list->ru_session[i];
+    if (ru_session->session == NULL)
+      continue;
+    MP_LOG_I("Disconnecting from RU \"%s\".\n", ru_session->ru_ip_add);
+    nc_session_free(ru_session->session, NULL);
+    ru_session->session = NULL;
+  }
+
+  nc_client_destroy();
+}

radio/fhi_72/mplane/connect-mplane.h

@@ -26,4 +26,6 @@
 
 bool connect_mplane(ru_session_t *ru_session);
 
+void disconnect_mplane(void *rus_disconnect);
+
 #endif /* CONNECT_MPLANE_H */

radio/fhi_72/mplane/init-mplane.c

@@ -186,6 +186,18 @@ bool manage_ru(ru_session_t *ru_session, const openair0_config_t *oai, const siz
     AssertError(success, return false, "[MPLANE] Unable to commit the RU configuration.\n");
   }
 
+  const char *usage_state = get_ru_xml_node(operational_ds, "usage-state");
+  MP_LOG_I("Usage state = \"%s\" for RU \"%s\".\n", usage_state, ru_session->ru_ip_add);
+  if (strcmp(usage_state, "busy") == 0) { // carriers are already activated
+    ru_session->ru_notif.rx_carrier_state = true;
+    ru_session->ru_notif.tx_carrier_state = true;
+    ru_session->ru_notif.config_change = true;
+  } else {
+    ru_session->ru_notif.rx_carrier_state = false;
+    ru_session->ru_notif.tx_carrier_state = false;
+    ru_session->ru_notif.config_change = false;
+  }
+
   free(operational_ds);
   free(watchdog_answer);
 

radio/fhi_72/mplane/ru-mplane-api.h

@@ -35,6 +35,7 @@ typedef struct {
   bool ptp_state;
   bool rx_carrier_state;
   bool tx_carrier_state;
+  bool config_change;
   // to be extended with any notification callback
 
 } ru_notif_t;

radio/fhi_72/mplane/subscribe-mplane.c

@@ -79,6 +79,8 @@ static void recv_notif_v2(struct lyd_node_inner *op, ru_notif_t *answer)
     } else { // "DISABLED" or "BUSY"
       answer->tx_carrier_state = false;
     }
+  } else if (strcmp(notif, "netconf-config-change") == 0) {
+    answer->config_change = true;
   }
 }