diff --git a/arch/arm/src/kinetis/kinetis_lpserial.c b/arch/arm/src/kinetis/kinetis_lpserial.c
index 117dd3de4a1..515f1f370e0 100644
--- a/arch/arm/src/kinetis/kinetis_lpserial.c
+++ b/arch/arm/src/kinetis/kinetis_lpserial.c
@@ -615,12 +615,12 @@ static int kinetis_ioctl(struct file *filep, int cmd, unsigned long arg)
 {
 #if defined(CONFIG_SERIAL_TERMIOS) || defined(CONFIG_SERIAL_TIOCSERGSTRUCT) || \
     defined(CONFIG_KINETIS_SERIALBRK_BSDCOMPAT)
-  struct inode           *inode = filep->f_inode;
-  struct uart_dev_s      *dev   = inode->i_private;
+  struct inode           *inode;
+  struct uart_dev_s      *dev;
   uint8_t regval;
 #endif
 #if defined(CONFIG_SERIAL_TERMIOS) || defined(CONFIG_KINETIS_SERIALBRK_BSDCOMPAT)
-  struct kinetis_dev_s   *priv  = (struct kinetis_dev_s *)dev->priv;
+  struct kinetis_dev_s   *priv;
   bool                   iflow = false;
   bool                   oflow = false;
 #endif
@@ -634,6 +634,10 @@ static int kinetis_ioctl(struct file *filep, int cmd, unsigned long arg)
   DEBUGASSERT(dev != NULL && dev->priv != NULL);
 #endif
 
+#if defined(CONFIG_SERIAL_TERMIOS) || defined(CONFIG_KINETIS_SERIALBRK_BSDCOMPAT)
+  priv  = (struct kinetis_dev_s *)dev->priv;
+#endif
+
   switch (cmd)
     {
 #ifdef CONFIG_SERIAL_TIOCSERGSTRUCT
diff --git a/arch/arm/src/kinetis/kinetis_serial.c b/arch/arm/src/kinetis/kinetis_serial.c
index b7c6aeebc76..0f2a4b2ee46 100644
--- a/arch/arm/src/kinetis/kinetis_serial.c
+++ b/arch/arm/src/kinetis/kinetis_serial.c
@@ -980,7 +980,7 @@ static int up_ioctl(struct file *filep, int cmd, unsigned long arg)
   uint8_t regval;
 #endif
 #if defined(CONFIG_SERIAL_TERMIOS) || defined(CONFIG_KINETIS_SERIALBRK_BSDCOMPAT)
-  struct up_dev_s   *priv  = (struct up_dev_s *)dev->priv;
+  struct up_dev_s   *priv;
   bool               iflow = false;
   bool               oflow = false;
 #endif
@@ -994,6 +994,10 @@ static int up_ioctl(struct file *filep, int cmd, unsigned long arg)
   DEBUGASSERT(dev != NULL && dev->priv != NULL);
 #endif
 
+#if defined(CONFIG_SERIAL_TERMIOS) || defined(CONFIG_KINETIS_SERIALBRK_BSDCOMPAT)
+  priv  = (struct up_dev_s *)dev->priv;
+#endif
+
   switch (cmd)
     {
 #ifdef CONFIG_SERIAL_TIOCSERGSTRUCT