diff --git a/configs/samv71-xult/src/sam_ethernet.c b/configs/samv71-xult/src/sam_ethernet.c
index c08097eaee..1278b4d6be 100644
--- a/configs/samv71-xult/src/sam_ethernet.c
+++ b/configs/samv71-xult/src/sam_ethernet.c
@@ -319,7 +319,7 @@ int arch_phy_irq(FAR const char *intf, xcpt_t handler, void *arg,
   else
     {
       nerr("ERROR: Unsupported interface: %s\n", intf);
-      return NULL;
+      return -EINVAL;
     }
 
   /* Disable interrupts until we are done.  This guarantees that the