diff --git a/arch/parisc/include/asm/socket.h b/arch/parisc/include/asm/socket.h
index 885472b..a658b09 100644
--- a/arch/parisc/include/asm/socket.h
+++ b/arch/parisc/include/asm/socket.h
@@ -24,6 +24,7 @@
 #define SO_RCVTIMEO	0x1006
 #define SO_ERROR	0x1007
 #define SO_TYPE		0x1008
+#define SO_PROTOCOL	0x1028
 #define SO_PEERNAME	0x2000
 
 #define SO_NO_CHECK	0x400b