diff --git a/arch/arm/src/samdl/sam_eic.c b/arch/arm/src/samdl/sam_eic.c
index e666154838..15c33811c2 100644
--- a/arch/arm/src/samdl/sam_eic.c
+++ b/arch/arm/src/samdl/sam_eic.c
@@ -83,7 +83,7 @@ static int sam_eic_isr(int irq, FAR void *context, FAR void *arg)
 
   for(bit=0;bit<SAM_IRQ_NEXTINTS;bit++)
     {
-      if(intflag >> bit & 0x1)
+      if (intflag >> bit & 0x1)
       {
         irq_dispatch(SAM_IRQ_EXTINT0 + bit, context);
       }
@@ -126,7 +126,13 @@ void sam_eic_dumpregs(void)
  * Name: sam_eic_initialize
  *
  * Description:
- *   Configure the external interrupt controller.
+ *   Initialize the external interrupt controller (EIC).
+ *
+ * Input Parameters:
+ *   gclkgen - GCLK Generator
+ *
+ * Returned Value:
+ *   None
  *
  ****************************************************************************/
 
@@ -151,12 +157,26 @@ int sam_eic_initialize(uint8_t gclkgen)
   return OK;
 }
 
+/****************************************************************************
+ * Name: sam_eic_initialize
+ *
+ * Description:
+ *   Enable a external interrupt.
+ *
+ * Input Parameters:
+ *   irq - SAM_IRQ_EXTINTn IRQ to be enabled
+ *
+ * Returned Value:
+ *   None
+ *
+ ****************************************************************************/
+
 int sam_eic_irq_enable(int irq)
 {
   uint32_t config;
   int eirq = irq - SAM_IRQ_EXTINT0;
 
-  config = getreg32(SAM_EIC_CONFIG0);
+  config  = getreg32(SAM_EIC_CONFIG0);
   config |= EIC_CONFIG0_FILTEN(eirq) | EIC_CONFIG0_SENSE_FALL(eirq);
   putreg32(config, SAM_EIC_CONFIG0);
 
@@ -165,6 +185,21 @@ int sam_eic_irq_enable(int irq)
   return OK;
 }
 
+/****************************************************************************
+ * Name: sam_eic_config
+ *
+ * Description:
+ *   Configure the interrupt edge sensitivity in CONFIGn register of the EIC
+ *
+ * Input Parameters:
+ *   eirq    - Pin to be configured
+ *   pinset  - Configuration of the pin
+ *
+ * Returned Value:
+ *   None
+ *
+ ****************************************************************************/
+
 int sam_eic_config(uint8_t eirq, port_pinset_t pinset)
 {
   uint32_t reg;
@@ -173,18 +208,24 @@ int sam_eic_config(uint8_t eirq, port_pinset_t pinset)
 
   /* Determine which of the CONFIG[0:2] registers to write to */
 
-  if(eirq < 8)
+  if (eirq < 8)
     {
       reg = SAM_EIC_CONFIG0;
     
       val = EIC_CONFIG0_SENSE_BOTH(eirq);
-      if(pinset & PORT_INT_RISING)
-        val = EIC_CONFIG0_SENSE_RISE(eirq);
-      if(pinset & PORT_INT_FALLING)
-        val = EIC_CONFIG0_SENSE_FALL(eirq);
+      if (pinset & PORT_INT_RISING)
+        {
+          val = EIC_CONFIG0_SENSE_RISE(eirq);
+        }
+
+      if (pinset & PORT_INT_FALLING)
+        {
+          val = EIC_CONFIG0_SENSE_FALL(eirq);
+        }
+
       val |= EIC_CONFIG0_FILTEN(eirq);
     }
-  else if(eirq < 16)
+  else if (eirq < 16)
     {
       reg = SAM_EIC_CONFIG1;
       val = EIC_CONFIG1_FILTEN(eirq) | EIC_CONFIG1_SENSE_FALL(eirq);
@@ -197,7 +238,7 @@ int sam_eic_config(uint8_t eirq, port_pinset_t pinset)
 
   /* Write the new config to the CONFIGn register */
 
-  config = getreg32(reg);
+  config  = getreg32(reg);
   config |= val;
   putreg32(config, reg);
 
@@ -206,6 +247,5 @@ int sam_eic_config(uint8_t eirq, port_pinset_t pinset)
   putreg32(EIC_EXTINT(eirq), SAM_EIC_INTENSET);
 
   sam_eic_dumpregs();
-
   return OK;
 }
diff --git a/arch/arm/src/samdl/sam_eic.h b/arch/arm/src/samdl/sam_eic.h
index b149d182ea..53fe547b36 100644
--- a/arch/arm/src/samdl/sam_eic.h
+++ b/arch/arm/src/samdl/sam_eic.h
@@ -57,19 +57,7 @@
 #endif
 
 /****************************************************************************
- * Pre-processor Definitions
- ****************************************************************************/
-
-/****************************************************************************
- * Public Types
- ****************************************************************************/
-
-/****************************************************************************
- * Inline Functions
- ****************************************************************************/
-
-/****************************************************************************
- * Public Data
+ * Public Function Prototypes
  ****************************************************************************/
 
 #undef EXTERN
@@ -82,14 +70,10 @@ extern "C"
 #endif
 
 /****************************************************************************
- * Public Function Prototypes
- ****************************************************************************/
-
-/****************************************************************************
- * Name: sam_eic_configure
+ * Name: sam_eic_initialize
  *
  * Description:
- *   Configure the EIC
+ *   Initialize the EIC
  *
  * Input Parameters:
  *   gclkgen - GCLK Generator
@@ -100,6 +84,22 @@ extern "C"
  ****************************************************************************/
 
 int sam_eic_initialize(uint8_t gclkgen);
+
+/****************************************************************************
+ * Name: sam_eic_config
+ *
+ * Description:
+ *   Configure the interrupt edge sensitivity in CONFIGn register of the EIC
+ *
+ * Input Parameters:
+ *   eirq    - Pin to be configured
+ *   pinset  - Configuration of the pin
+ *
+ * Returned Value:
+ *   None
+ *
+ ****************************************************************************/
+
 int sam_eic_config(uint8_t eirq, port_pinset_t pinset);
 
 #undef EXTERN
diff --git a/arch/arm/src/samdl/sam_port.c b/arch/arm/src/samdl/sam_port.c
index 19be6f030f..7faaa6c44f 100644
--- a/arch/arm/src/samdl/sam_port.c
+++ b/arch/arm/src/samdl/sam_port.c
@@ -1,7 +1,7 @@
 /****************************************************************************
  * arch/arm/src/samdl/sam_port.c
  *
- *   Copyright (C) 2014-2016 Gregory Nutt. All rights reserved.
+ *   Copyright (C) 2014-2016, 2018 Gregory Nutt. All rights reserved.
  *   Author: Gregory Nutt <gnutt@nuttx.org>
  *
  * References:
@@ -204,9 +204,11 @@ static inline void sam_configinterrupt(uintptr_t base, port_pinset_t pinset)
 
   putreg32(regval, base + SAM_PORT_WRCONFIG_OFFSET);
 
+#ifdef CONFIG_SAMDL_EIC
   /* Configure the interrupt edge sensitivity in CONFIGn register of the EIC */
 
   sam_eic_config(pin, pinset);
+#endif
 
 #ifdef CONFIG_DEBUG_GPIO_INFO
   sam_dumpport(pinset, "extint");