From bc75971fc8557ce2d05a97ff245eb4efd8911af8 Mon Sep 17 00:00:00 2001
From: BlackMark <me@blackmark.me>
Date: Fri, 3 Jul 2020 20:54:39 +0200
Subject: [PATCH] Fix missing early exit for empty flush

---
 AdaptiveBrightnessFirmware/Inc/uart_vcp.hpp | 3 +++
 1 file changed, 3 insertions(+)

diff --git a/AdaptiveBrightnessFirmware/Inc/uart_vcp.hpp b/AdaptiveBrightnessFirmware/Inc/uart_vcp.hpp
index 0d849e4..67d7108 100644
--- a/AdaptiveBrightnessFirmware/Inc/uart_vcp.hpp
+++ b/AdaptiveBrightnessFirmware/Inc/uart_vcp.hpp
@@ -74,6 +74,9 @@ class VirtualComPort {
 
     [[gnu::always_inline]] static void flushTx()
     {
+        if(m_txBuffer.size == 0)
+            return;
+
         constexpr auto usbReady = []() {
             USBD_CDC_HandleTypeDef* hcdc = static_cast<USBD_CDC_HandleTypeDef*>(hUsbDeviceFS.pClassData);
             return hcdc->TxState != 0;