diff --git a/arch/arm/src/samdl/chip/samd_eic.h b/arch/arm/src/samdl/chip/samd_eic.h
index 9bbd0dc4feb..adc89821244 100644
--- a/arch/arm/src/samdl/chip/samd_eic.h
+++ b/arch/arm/src/samdl/chip/samd_eic.h
@@ -6,7 +6,7 @@
  *           Matt Thompson <matt@extent3d.com>
  *
  * References:
- *   "Microchip SAMD21 datasheet" 
+ *   "Microchip SAMD21 datasheet"
  *
  * Redistribution and use in source and binary forms, with or without
  * modification, are permitted provided that the following conditions
@@ -116,7 +116,6 @@
 
 #define EIC_EXTINT_SHIFT             (0)       /* Bits 0-15: External interrupt n */
 #define EIC_EXTINT_MASK              (0x3ffff << EIC_EXTINT_SHIFT)
-//#  define EIC_EXTINT(n)              ((uint32_t)(n) << EIC_EXTINT_SHIFT)
 #  define EIC_EXTINT(n)              (1 << (n))
 #  define EIC_EXTINT_0               (1 << 0)  /* Bit 0: External interrupt 0 */
 #  define EIC_EXTINT_1               (1 << 1)  /* Bit 1: External interrupt 1 */
diff --git a/arch/arm/src/samdl/chip/saml_eic.h b/arch/arm/src/samdl/chip/saml_eic.h
index e6bb167e2eb..56d91824ec4 100644
--- a/arch/arm/src/samdl/chip/saml_eic.h
+++ b/arch/arm/src/samdl/chip/saml_eic.h
@@ -123,7 +123,7 @@
 
 #define EIC_EXTINT_SHIFT             (0)       /* Bits 0-15: External interrupt n */
 #define EIC_EXTINT_MASK              (0xffff << EIC_EXTINT_SHIFT)
-#  define EIC_EXTINT(n)              ((uint32_t)(n) << EIC_EXTINT_SHIFT)
+#  define EIC_EXTINT(n)              (1 << (n))
 #  define EIC_EXTINT_0               (1 << 0)  /* Bit 0: External interrupt 0 */
 #  define EIC_EXTINT_1               (1 << 1)  /* Bit 1: External interrupt 1 */
 #  define EIC_EXTINT_2               (1 << 2)  /* Bit 2: External interrupt 2 */
diff --git a/arch/arm/src/samdl/sam_eic.c b/arch/arm/src/samdl/sam_eic.c
index 15c33811c25..ff73950cc0f 100644
--- a/arch/arm/src/samdl/sam_eic.c
+++ b/arch/arm/src/samdl/sam_eic.c
@@ -84,15 +84,15 @@ 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)
-      {
-        irq_dispatch(SAM_IRQ_EXTINT0 + bit, context);
-      }
+        {
+          irq_dispatch(SAM_IRQ_EXTINT0 + bit, context);
+        }
     }
 
   /* Clear the pending interrupt flags */
 
   putreg32(EIC_EXTINT_ALL, SAM_EIC_INTFLAG);
-  
+
   return 0;
 }
 
@@ -145,7 +145,7 @@ int sam_eic_initialize(uint8_t gclkgen)
   regval = GCLK_CLKCTRL_ID_EIC | GCLK_CLKCTRL_GEN(gclkgen) | GCLK_CLKCTRL_CLKEN;
   putreg16(regval, SAM_GCLK_CLKCTRL);
 
-  putreg8(EIC_CTRLA_ENABLE, SAM_EIC_CTRLA);  
+  putreg8(EIC_CTRLA_ENABLE, SAM_EIC_CTRLA);
   sam_eic_syncwait();
 
   irq_attach(SAM_IRQ_EIC, sam_eic_isr, NULL);
@@ -211,7 +211,7 @@ int sam_eic_config(uint8_t eirq, port_pinset_t pinset)
   if (eirq < 8)
     {
       reg = SAM_EIC_CONFIG0;
-    
+
       val = EIC_CONFIG0_SENSE_BOTH(eirq);
       if (pinset & PORT_INT_RISING)
         {
diff --git a/arch/arm/src/samdl/sam_eic.h b/arch/arm/src/samdl/sam_eic.h
index 53fe547b363..d60c936cef5 100644
--- a/arch/arm/src/samdl/sam_eic.h
+++ b/arch/arm/src/samdl/sam_eic.h
@@ -85,6 +85,22 @@ extern "C"
 
 int sam_eic_initialize(uint8_t gclkgen);
 
+/****************************************************************************
+ * 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);
+
 /****************************************************************************
  * Name: sam_eic_config
  *
diff --git a/arch/arm/src/samdl/sam_port.c b/arch/arm/src/samdl/sam_port.c
index 7faaa6c44fb..df35aae65a7 100644
--- a/arch/arm/src/samdl/sam_port.c
+++ b/arch/arm/src/samdl/sam_port.c
@@ -190,13 +190,15 @@ static inline void sam_configinput(uintptr_t base, port_pinset_t pinset)
 
 static inline void sam_configinterrupt(uintptr_t base, port_pinset_t pinset)
 {
+#ifdef CONFIG_SAMDL_EIC
   uint32_t func;
   uint32_t regval;
   int pin;
 
-  pin = (pinset & PORT_PIN_MASK) >> PORT_PIN_SHIFT;
+  pin     = (pinset & PORT_PIN_MASK) >> PORT_PIN_SHIFT;
 
-  regval = (PORT_WRCONFIG_WRPINCFG | PORT_WRCONFIG_WRPMUX | PORT_WRCONFIG_PMUXEN | PORT_WRCONFIG_INEN);
+  regval  = (PORT_WRCONFIG_WRPINCFG | PORT_WRCONFIG_WRPMUX |
+             PORT_WRCONFIG_PMUXEN | PORT_WRCONFIG_INEN);
   regval |= PORT_WRCONFIG_PINMASK(pin);
 
   func    = (pinset & PORT_FUNC_MASK) >> PORT_FUNC_SHIFT;
@@ -204,15 +206,14 @@ 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");
 #endif
+#endif /* CONFIG_SAMDL_EIC */
 }
 
 /****************************************************************************
@@ -554,7 +555,7 @@ int sam_dumpport(uint32_t pinset, const char *msg)
 
   /* Get the base address associated with the PIO port */
 
-  pin = (pinset & PORT_PIN_MASK) >> PORT_PIN_SHIFT;
+  pin  = (pinset & PORT_PIN_MASK) >> PORT_PIN_SHIFT;
   port = (pinset & PORT_MASK) >> PORT_SHIFT;
   base = SAM_PORTN_BASE(port);