diff --git a/arch/arm/src/kinetis/kinetis_enet.c b/arch/arm/src/kinetis/kinetis_enet.c
index 6c30bac415..dc0be25e16 100644
--- a/arch/arm/src/kinetis/kinetis_enet.c
+++ b/arch/arm/src/kinetis/kinetis_enet.c
@@ -1840,7 +1840,7 @@ static inline int kinetis_initphy(struct kinetis_driver_s *priv)
           phydata = 0xffff;
           ret = kinetis_readmii(priv, phyaddr, MII_PHYID1, &phydata);
         }
-      while (ret >= 0 && phydata == 0xffff && ++retries < 3);
+      while ((ret < 0 || phydata == 0xffff) && ++retries < 3);
 
       /* If we successfully read anything then break out, using this PHY address */