From 1c3f30be0140379d660b8ab18746fdb6f677a364 Mon Sep 17 00:00:00 2001
From: =?UTF-8?q?Beat=20K=C3=BCng?= <beat-kueng@gmx.net>
Date: Thu, 17 Jun 2021 12:07:39 +0200
Subject: [PATCH] protocol_splitter: tcflush() uart before closing it

---
 src/drivers/protocol_splitter/protocol_splitter.cpp | 3 +++
 1 file changed, 3 insertions(+)

diff --git a/src/drivers/protocol_splitter/protocol_splitter.cpp b/src/drivers/protocol_splitter/protocol_splitter.cpp
index 0ba92dea08..e6c5d86f58 100644
--- a/src/drivers/protocol_splitter/protocol_splitter.cpp
+++ b/src/drivers/protocol_splitter/protocol_splitter.cpp
@@ -47,6 +47,7 @@
 #include <sys/ioctl.h>
 #include <assert.h>
 #include <unistd.h>
+#include <termios.h>
 #include <cstdint>
 #include <string.h>
 
@@ -220,6 +221,8 @@ DevCommon::DevCommon(const char *device_path)
 DevCommon::~DevCommon()
 {
 	if (_fd >= 0) {
+		/* discard all pending data, as close() might block otherwise on NuttX with flow control enabled */
+		tcflush(_fd, TCIOFLUSH);
 		::close(_fd);
 	}
 }