diff --git a/arch/arm/src/imx6/imx_iomuxc.c b/arch/arm/src/imx6/imx_iomuxc.c
index 8d7562b4d1..ff5e9bc3b7 100644
--- a/arch/arm/src/imx6/imx_iomuxc.c
+++ b/arch/arm/src/imx6/imx_iomuxc.c
@@ -39,6 +39,7 @@
 
 #include <nuttx/config.h>
 
+#include <sys/types.h>
 #include <stdint.h>
 #include <assert.h>
 #include <errno.h>