From cb94997553a90f50488d0d2d277a871e8c641a2f Mon Sep 17 00:00:00 2001
From: Stefano Avallone <stavallo@unina.it>
Date: Tue, 30 May 2023 16:21:01 +0200
Subject: [PATCH] wifi: Main PHY takes over UL TXOP after aux PHY has
 transmitted RTS

---
 src/wifi/model/eht/emlsr-manager.cc | 15 +++++++++++++++
 1 file changed, 15 insertions(+)

diff --git a/src/wifi/model/eht/emlsr-manager.cc b/src/wifi/model/eht/emlsr-manager.cc
index ebf4a2401..dd227b45b 100644
--- a/src/wifi/model/eht/emlsr-manager.cc
+++ b/src/wifi/model/eht/emlsr-manager.cc
@@ -28,6 +28,7 @@
 #include "ns3/log.h"
 #include "ns3/wifi-mpdu.h"
 #include "ns3/wifi-net-device.h"
+#include "ns3/wifi-phy-state-helper.h"
 
 namespace ns3
 {
@@ -289,6 +290,20 @@ EmlsrManager::NotifyUlTxopStart(uint8_t linkId)
             m_staMac->BlockTxOnLink(id, WifiQueueBlockedReason::USING_OTHER_EMLSR_LINK);
         }
     }
+
+    // if this TXOP is being started by an aux PHY, wait until the end of RTS transmission
+    // and then have the main PHY take over the TXOP on this link
+    if (m_staMac->GetLinkForPhy(m_mainPhyId) != linkId)
+    {
+        auto stateHelper = m_staMac->GetWifiPhy(linkId)->GetState();
+        NS_ASSERT(stateHelper);
+        NS_ASSERT_MSG(stateHelper->GetState() == TX,
+                      "Expecting the aux PHY to be transmitting (an RTS frame)");
+        Simulator::Schedule(stateHelper->GetDelayUntilIdle(),
+                            &EmlsrManager::SwitchMainPhy,
+                            this,
+                            linkId);
+    }
 }
 
 void