From 7236e742ab2abf692db3c5a60b649f0e00c572e2 Mon Sep 17 00:00:00 2001
From: Manuel Stuehn <manuel.stuehn@gmx.net>
Date: Wed, 3 Feb 2016 08:24:49 -0600
Subject: [PATCH] STM32 Ethernet:  Fix a cornercase where the TX poll timer is
 not restarted.

---
 arch/arm/src/stm32/stm32_eth.c | 13 +++++++++++--
 1 file changed, 11 insertions(+), 2 deletions(-)

diff --git a/arch/arm/src/stm32/stm32_eth.c b/arch/arm/src/stm32/stm32_eth.c
index 835ea58c74..3838f79cdb 100644
--- a/arch/arm/src/stm32/stm32_eth.c
+++ b/arch/arm/src/stm32/stm32_eth.c
@@ -1908,10 +1908,11 @@ static void stm32_freeframe(FAR struct stm32_ethmac_s *priv)
  * Function: stm32_txdone
  *
  * Description:
- *   An interrupt was received indicating that the last TX packet(s) is done
+ *   An interrupt was received indicating that the last TX packet
+ *  transfer(s) are complete.
  *
  * Parameters:
- *   priv  - Reference to the driver state structure
+ *   priv - Reference to the driver state structure
  *
  * Returned Value:
  *   None
@@ -1933,8 +1934,16 @@ static void stm32_txdone(FAR struct stm32_ethmac_s *priv)
 
   if (priv->inflight <= 0)
     {
+      /* Cancel the TX timeout */
+
       wd_cancel(priv->txtimeout);
 
+      /* Then make sure that the TX poll timer is running (if it is already
+       * running, the following would restart it).
+       */
+
+      (void)wd_start(priv->txpoll, STM32_WDDELAY, stm32_poll_expiry, 1, priv);
+
       /* And disable further TX interrupts. */
 
       stm32_disableint(priv, ETH_DMAINT_TI);