From f7e238afddd753cb29a0db58207c7213d92bfe49 Mon Sep 17 00:00:00 2001
From: Stefan Wahren <info@lategoodbye.de>
Date: Wed, 3 Oct 2012 23:31:37 +0200
Subject: [PATCH] Extend mbus_recv_frame with simple echo cancelation

---
 mbus/mbus-protocol-aux.c | 7 +++++++
 1 file changed, 7 insertions(+)

diff --git a/mbus/mbus-protocol-aux.c b/mbus/mbus-protocol-aux.c
index 57758eb..dd6ddb5 100755
--- a/mbus/mbus-protocol-aux.c
+++ b/mbus/mbus-protocol-aux.c
@@ -1467,6 +1467,13 @@ mbus_recv_frame(mbus_handle * handle, mbus_frame *frame)
     }
 
     result = handle->recv(handle, frame);
+    
+    /* frame valid, but wrong direction */
+    if (mbus_frame_direction(frame) == MBUS_CONTROL_MASK_DIR_M2S)
+    {
+        /* purge echo and retry (echo cancelation) */
+        result = handle->recv(handle, frame);
+    }
 
     if (frame != NULL)
     {