diff --git a/src/add-ons/kernel/bus_managers/firewire/fwohcireg.h b/src/add-ons/kernel/bus_managers/firewire/fwohcireg.h
index 2eb83e882e..674479dbf7 100644
--- a/src/add-ons/kernel/bus_managers/firewire/fwohcireg.h
+++ b/src/add-ons/kernel/bus_managers/firewire/fwohcireg.h
@@ -94,8 +94,8 @@ typedef uint32_t 	fwohcireg_t;
 /* for PCI */
 #if BYTE_ORDER == BIG_ENDIAN
 #ifdef __HAIKU__
-#define htole32(x) __swap_int32(x)
-#define le32toh(x) __swap_int32(x)
+#define htole32(x) ((uint32_t)__swap_int32(x))
+#define le32toh(x) ((uint32_t)__swap_int32(x))
 #endif
 #define FWOHCI_DMA_WRITE(x, y)	((x) = htole32(y))
 #define FWOHCI_DMA_READ(x)	le32toh(x)