From 940e108c4b5b90ae2d4bbdb6207078d383e59702 Mon Sep 17 00:00:00 2001
From: aleks <aleks@espressif.com>
Date: Wed, 13 May 2020 15:59:36 +0200
Subject: [PATCH] freemodbus: fix event processing failure after destroy

Closes https://github.com/espressif/esp-idf/issues/5275
---
 components/freemodbus/port/portevent_m.c | 7 ++++++-
 1 file changed, 6 insertions(+), 1 deletion(-)

diff --git a/components/freemodbus/port/portevent_m.c b/components/freemodbus/port/portevent_m.c
index 33814ebe72..1c990005f9 100644
--- a/components/freemodbus/port/portevent_m.c
+++ b/components/freemodbus/port/portevent_m.c
@@ -274,7 +274,12 @@ eMBMasterReqErrCode eMBMasterWaitRequestFinish( void ) {
         }
     } else {
         ESP_LOGE(MB_PORT_TAG,"%s: Incorrect event or timeout xRecvedEvent = 0x%x", __func__, uxBits);
-        assert(0);
+        // https://github.com/espressif/esp-idf/issues/5275
+        // if a no event is received, that means vMBMasterPortEventClose()
+        // has been closed, so event group has been deleted by FreeRTOS, which
+        // triggers the send of 0 value to the event group to unlock this task
+        // waiting on it. For this patch, handles it as a time out without assert.
+        eErrStatus = MB_MRE_TIMEDOUT;
     }
     return eErrStatus;
 }