From d2358743d776c32f721dca668ec2e5841b287190 Mon Sep 17 00:00:00 2001
From: gdisirio <gdisirio@35acf78f-673a-0410-8e92-d51de3d6d3f4>
Date: Wed, 14 May 2014 08:21:58 +0000
Subject: [PATCH] Fixed bug #503.

git-svn-id: svn://svn.code.sf.net/p/chibios/svn/trunk@6935 35acf78f-673a-0410-8e92-d51de3d6d3f4
---
 os/hal/ports/STM32/LLD/USARTv1/serial_lld.c | 9 +++++----
 os/hal/ports/STM32/LLD/USARTv2/serial_lld.c | 9 +++++++--
 2 files changed, 12 insertions(+), 6 deletions(-)

diff --git a/os/hal/ports/STM32/LLD/USARTv1/serial_lld.c b/os/hal/ports/STM32/LLD/USARTv1/serial_lld.c
index 87be9bbb6..1991c6ae0 100644
--- a/os/hal/ports/STM32/LLD/USARTv1/serial_lld.c
+++ b/os/hal/ports/STM32/LLD/USARTv1/serial_lld.c
@@ -159,8 +159,8 @@ static void serve_interrupt(SerialDriver *sdp) {
   if (sr & USART_SR_LBD) {
     osalSysLockFromISR();
     chnAddFlagsI(sdp, SD_BREAK_DETECTED);
-    osalSysUnlockFromISR();
     u->SR = ~USART_SR_LBD;
+    osalSysUnlockFromISR();
   }
 
   /* Data available.*/
@@ -191,10 +191,11 @@ static void serve_interrupt(SerialDriver *sdp) {
   /* Physical transmission end.*/
   if (sr & USART_SR_TC) {
     osalSysLockFromISR();
-    chnAddFlagsI(sdp, CHN_TRANSMISSION_END);
-    osalSysUnlockFromISR();
-    u->CR1 = cr1 & ~(USART_CR1_TXEIE | USART_CR1_TCIE);
+    if (oqIsEmptyI(&sdp->oqueue))
+      chnAddFlagsI(sdp, CHN_TRANSMISSION_END);
+    u->CR1 = cr1 & ~USART_CR1_TCIE;
     u->SR = ~USART_SR_TC;
+    osalSysUnlockFromISR();
   }
 }
 
diff --git a/os/hal/ports/STM32/LLD/USARTv2/serial_lld.c b/os/hal/ports/STM32/LLD/USARTv2/serial_lld.c
index 38042003e..3ecf1fcbf 100644
--- a/os/hal/ports/STM32/LLD/USARTv2/serial_lld.c
+++ b/os/hal/ports/STM32/LLD/USARTv2/serial_lld.c
@@ -155,18 +155,21 @@ static void serve_interrupt(SerialDriver *sdp) {
   /* Error condition detection.*/
   if (isr & (USART_ISR_ORE | USART_ISR_NE | USART_ISR_FE  | USART_ISR_PE))
     set_error(sdp, isr);
+
   /* Special case, LIN break detection.*/
   if (isr & USART_ISR_LBD) {
     osalSysLockFromISR();
     chnAddFlagsI(sdp, SD_BREAK_DETECTED);
     osalSysUnlockFromISR();
   }
+
   /* Data available.*/
   if (isr & USART_ISR_RXNE) {
     osalSysLockFromISR();
     sdIncomingDataI(sdp, (uint8_t)u->RDR);
     osalSysUnlockFromISR();
   }
+
   /* Transmission buffer empty.*/
   if ((cr1 & USART_CR1_TXEIE) && (isr & USART_ISR_TXE)) {
     msg_t b;
@@ -180,12 +183,14 @@ static void serve_interrupt(SerialDriver *sdp) {
       u->TDR = b;
     osalSysUnlockFromISR();
   }
+
   /* Physical transmission end.*/
   if (isr & USART_ISR_TC) {
     osalSysLockFromISR();
-    chnAddFlagsI(sdp, CHN_TRANSMISSION_END);
-    osalSysUnlockFromISR();
+    if (oqIsEmptyI(&sdp->oqueue))
+      chnAddFlagsI(sdp, CHN_TRANSMISSION_END);
     u->CR1 = cr1 & ~USART_CR1_TCIE;
+    osalSysUnlockFromISR();
   }
 }