diff --git a/include/nuttx/wireless/ieee802154/ieee802154_mac.h b/include/nuttx/wireless/ieee802154/ieee802154_mac.h
index 2f78ec443f1..95ccf10ecd2 100644
--- a/include/nuttx/wireless/ieee802154/ieee802154_mac.h
+++ b/include/nuttx/wireless/ieee802154/ieee802154_mac.h
@@ -1327,8 +1327,8 @@ union ieee802154_mcps_notify_u
 
 union ieee802154_macarg_u
 {
-  /* To be determined */                        /* MAC802154IOC_MCPS_REGISTER */
-  /* To be determined */                        /* MAC802154IOC_MLME_REGISTER */
+  union  ieee802154_mcps_notify_u  mcpsnotify;  /* MAC802154IOC_MCPS_REGISTER */
+  union  ieee802154_mlme_notify_u  mlmenotify;  /* MAC802154IOC_MLME_REGISTER */
   struct ieee802154_assoc_req_s    assocreq;    /* MAC802154IOC_MLME_ASSOC_REQUEST */
   struct ieee802154_assoc_resp_s   assocresp;   /* MAC802154IOC_MLME_ASSOC_RESPONSE */
   struct ieee802154_disassoc_req_s disassocreq; /* MAC802154IOC_MLME_DISASSOC_REQUEST */