diff --git a/src/csr.h b/src/csr.h
index 13f7c13..bf82463 100644
--- a/src/csr.h
+++ b/src/csr.h
@@ -1,3 +1,5 @@
+#ifndef _LIBRAW1394_CSR_H
+#define _LIBRAW1394_CSR_H
 
 #define CSR_REGISTER_BASE  0xfffff0000000ULL
 
@@ -17,7 +19,12 @@
 #define CSR_CHANNELS_AVAILABLE_LO 0x228
 #define CSR_CONFIG_ROM            0x400
 #define CSR_CONFIG_ROM_END        0x800
+#define CSR_FCP_COMMAND           0xB00
+#define CSR_FCP_RESPONSE          0xD00
+#define CSR_FCP_END               0xF00
 #define CSR_TOPOLOGY_MAP          0x1000
 #define CSR_TOPOLOGY_MAP_END      0x1400
 #define CSR_SPEED_MAP             0x2000
 #define CSR_SPEED_MAP_END         0x3000
+
+#endif /* _LIBRAW1394_CSR_H */