diff --git a/nuttx-patches/i2c_hotfix.patch b/nuttx-patches/i2c_hotfix.patch
index c7eef298f331..dcd68c0c9f02 100644
--- a/nuttx-patches/i2c_hotfix.patch
+++ b/nuttx-patches/i2c_hotfix.patch
@@ -1,5 +1,5 @@
 diff --git NuttX/nuttx/arch/arm/src/stm32/stm32_i2c.c NuttX/nuttx/arch/arm/src/stm32/stm32_i2c.c
-index 631ba66..654d18a 100644
+index 631ba66..669e0db 100644
 --- NuttX/nuttx/arch/arm/src/stm32/stm32_i2c.c
 +++ NuttX/nuttx/arch/arm/src/stm32/stm32_i2c.c
 @@ -7,7 +7,7 @@
@@ -31,8 +31,30 @@ index 631ba66..654d18a 100644
      }
  
    /* Loop until the transfer is complete. */
+@@ -729,6 +729,10 @@ static inline void stm32_i2c_sem_waitstop(FAR struct stm32_i2c_priv_s *priv)
+   start = clock_systimer();
+   do
+     {
++      /* Calculate the elapsed time */
++
++      elapsed = clock_systimer() - start;
++
+       /* Check for STOP condition */
+ 
+       cr1 = stm32_i2c_getreg(priv, STM32_I2C_CR1_OFFSET);
+@@ -744,10 +748,6 @@ static inline void stm32_i2c_sem_waitstop(FAR struct stm32_i2c_priv_s *priv)
+         {
+           return;
+         }
+-
+-      /* Calculate the elapsed time */
+-
+-      elapsed = clock_systimer() - start;
+     }
+ 
+   /* Loop until the stop is complete or a timeout occurs. */
 diff --git NuttX/nuttx/arch/arm/src/stm32/stm32_i2c_alt.c NuttX/nuttx/arch/arm/src/stm32/stm32_i2c_alt.c
-index 545a647..61cea4e 100644
+index 545a647..981edb6 100644
 --- NuttX/nuttx/arch/arm/src/stm32/stm32_i2c_alt.c
 +++ NuttX/nuttx/arch/arm/src/stm32/stm32_i2c_alt.c
 @@ -7,7 +7,7 @@
@@ -64,8 +86,29 @@ index 545a647..61cea4e 100644
      }
  
    /* Loop until the transfer is complete. */
+@@ -737,6 +737,10 @@ static inline void stm32_i2c_sem_waitstop(FAR struct stm32_i2c_priv_s *priv)
+   start = clock_systimer();
+   do
+     {
++      /* Calculate the elapsed time */
++
++      elapsed = clock_systimer() - start;
++
+       /* Check for STOP condition */
+ 
+       cr1 = stm32_i2c_getreg(priv, STM32_I2C_CR1_OFFSET);
+@@ -753,9 +757,6 @@ static inline void stm32_i2c_sem_waitstop(FAR struct stm32_i2c_priv_s *priv)
+           return;
+         }
+ 
+-      /* Calculate the elapsed time */
+-
+-      elapsed = clock_systimer() - start;
+     }
+ 
+   /* Loop until the stop is complete or a timeout occurs. */
 diff --git NuttX/nuttx/arch/arm/src/stm32/stm32f30xxx_i2c.c NuttX/nuttx/arch/arm/src/stm32/stm32f30xxx_i2c.c
-index 312e0b4..193ccb8 100644
+index 312e0b4..b2da861 100644
 --- NuttX/nuttx/arch/arm/src/stm32/stm32f30xxx_i2c.c
 +++ NuttX/nuttx/arch/arm/src/stm32/stm32f30xxx_i2c.c
 @@ -7,7 +7,7 @@
@@ -97,8 +140,29 @@ index 312e0b4..193ccb8 100644
      }
  
    /* Loop until the transfer is complete. */
+@@ -844,6 +844,10 @@ static inline void stm32_i2c_sem_waitstop(FAR struct stm32_i2c_priv_s *priv)
+   start = clock_systimer();
+   do
+     {
++      /* Calculate the elapsed time */
++
++      elapsed = clock_systimer() - start;
++
+       /* Check for STOP condition */
+ 
+       cr = stm32_i2c_getreg32(priv, STM32_I2C_CR2_OFFSET);
+@@ -860,9 +864,6 @@ static inline void stm32_i2c_sem_waitstop(FAR struct stm32_i2c_priv_s *priv)
+           return;
+         }
+ 
+-      /* Calculate the elapsed time */
+-
+-      elapsed = clock_systimer() - start;
+     }
+ 
+   /* Loop until the stop is complete or a timeout occurs. */
 diff --git NuttX/nuttx/arch/arm/src/stm32/stm32f40xxx_i2c.c NuttX/nuttx/arch/arm/src/stm32/stm32f40xxx_i2c.c
-index 2bb715c..974fab8 100644
+index 2bb715c..e91058a 100644
 --- NuttX/nuttx/arch/arm/src/stm32/stm32f40xxx_i2c.c
 +++ NuttX/nuttx/arch/arm/src/stm32/stm32f40xxx_i2c.c
 @@ -7,7 +7,7 @@
@@ -130,10 +194,40 @@ index 2bb715c..974fab8 100644
      }
  
    /* Loop until the transfer is complete. */
+@@ -731,6 +731,10 @@ static inline void stm32_i2c_sem_waitstop(FAR struct stm32_i2c_priv_s *priv)
+   start = clock_systimer();
+   do
+     {
++      /* Calculate the elapsed time */
++
++      elapsed = clock_systimer() - start;
++
+       /* Check for STOP condition */
+ 
+       cr1 = stm32_i2c_getreg(priv, STM32_I2C_CR1_OFFSET);
+@@ -747,9 +751,6 @@ static inline void stm32_i2c_sem_waitstop(FAR struct stm32_i2c_priv_s *priv)
+           return;
+         }
+ 
+-      /* Calculate the elapsed time */
+-
+-      elapsed = clock_systimer() - start;
+     }
+ 
+   /* Loop until the stop is complete or a timeout occurs. */
 diff --git NuttX/nuttx/arch/arm/src/stm32f7/stm32_i2c.c NuttX/nuttx/arch/arm/src/stm32f7/stm32_i2c.c
-index d089db9..1b5951d 100644
+index d089db9..fd73457 100644
 --- NuttX/nuttx/arch/arm/src/stm32f7/stm32_i2c.c
 +++ NuttX/nuttx/arch/arm/src/stm32f7/stm32_i2c.c
+@@ -7,7 +7,7 @@
+  *
+  * With extensions and modifications for the F1, F2, and F4 by:
+  *
+- *   Copyright (C) 2016 Gregory Nutt. All rights reserved.
++ *   Copyright (C) 2016-2017 Gregory Nutt. All rights reserved.
+  *   Authors: Gregroy Nutt <gnutt@nuttx.org>
+  *            John Wharington
+  *            David Sidrane <david_s5@nscdg.com>
 @@ -897,15 +897,15 @@ static inline int stm32_i2c_sem_waitdone(FAR struct stm32_i2c_priv_s *priv)
  
    do
@@ -154,8 +248,29 @@ index d089db9..1b5951d 100644
      }
  
    /* Loop until the transfer is complete. */
+@@ -1034,6 +1034,10 @@ static inline void stm32_i2c_sem_waitstop(FAR struct stm32_i2c_priv_s *priv)
+   start = clock_systimer();
+   do
+     {
++      /* Calculate the elapsed time */
++
++      elapsed = clock_systimer() - start;
++
+       /* Check for STOP condition */
+ 
+       cr = stm32_i2c_getreg32(priv, STM32_I2C_CR2_OFFSET);
+@@ -1050,9 +1054,6 @@ static inline void stm32_i2c_sem_waitstop(FAR struct stm32_i2c_priv_s *priv)
+           return;
+         }
+ 
+-      /* Calculate the elapsed time */
+-
+-      elapsed = clock_systimer() - start;
+     }
+ 
+   /* Loop until the stop is complete or a timeout occurs. */
 diff --git NuttX/nuttx/arch/arm/src/stm32l4/stm32l4_i2c.c NuttX/nuttx/arch/arm/src/stm32l4/stm32l4_i2c.c
-index eed199f..d5027bf 100644
+index eed199f..be46524 100644
 --- NuttX/nuttx/arch/arm/src/stm32l4/stm32l4_i2c.c
 +++ NuttX/nuttx/arch/arm/src/stm32l4/stm32l4_i2c.c
 @@ -4,7 +4,7 @@
@@ -187,3 +302,24 @@ index eed199f..d5027bf 100644
      }
  
    /* Loop until the transfer is complete. */
+@@ -788,6 +788,10 @@ static inline void stm32l4_i2c_sem_waitstop(FAR struct stm32l4_i2c_priv_s *priv)
+   start = clock_systimer();
+   do
+     {
++      /* Calculate the elapsed time */
++
++      elapsed = clock_systimer() - start;
++
+       /* Check for STOP condition */
+ 
+       cr = stm32l4_i2c_getreg32(priv, STM32L4_I2C_CR2_OFFSET);
+@@ -804,9 +808,6 @@ static inline void stm32l4_i2c_sem_waitstop(FAR struct stm32l4_i2c_priv_s *priv)
+           return;
+         }
+ 
+-      /* Calculate the elapsed time */
+-
+-      elapsed = clock_systimer() - start;
+     }
+ 
+   /* Loop until the stop is complete or a timeout occurs. */