-#define PVR_440SP_RA 0x53221850
-#define PVR_440SP_RB 0x53221891
-#define PVR_440SPe_RA 0x53421890
-#define PVR_440SPe_RB 0x53421891
+#define PVR_440SP_6_RAB 0x53221850 /* 440SP rev A&B with RAID 6 support enabled */
+#define PVR_440SP_RAB 0x53321850 /* 440SP rev A&B without RAID 6 support */
+#define PVR_440SP_6_RC 0x53221891 /* 440SP rev C with RAID 6 support enabled */
+#define PVR_440SP_RC 0x53321891 /* 440SP rev C without RAID 6 support */
+#define PVR_440SPe_6_RA 0x53421890 /* 440SPe rev A with RAID 6 support enabled */
+#define PVR_440SPe_RA 0x53521890 /* 440SPe rev A without RAID 6 support */
+#define PVR_440SPe_6_RB 0x53421891 /* 440SPe rev B with RAID 6 support enabled */
+#define PVR_440SPe_RB 0x53521891 /* 440SPe rev B without RAID 6 support */