-#define MPIOPORTMAP _IOW(m,1, struct protports)
-#define MPIOHILO _IOW(m,3, short)
-#define MPIOENDCODE _IO(m,4)
-#define MPIOASYNCNF _IOW(m,7, struct abdcf)
-#define MPIOENDDL _IO(m,10)
-#define MPIOSTARTDL _IO(m,11)
-#define MPIORESETBOARD _IO(m,12)
+#define MPIOPORTMAP _IOW('m',1, struct protports)
+#define MPIOHILO _IOW('m',3, short)
+#define MPIOENDCODE _IO('m',4)
+#define MPIOASYNCNF _IOW('m',7, struct abdcf)
+#define MPIOENDDL _IO('m',10)
+#define MPIOSTARTDL _IO('m',11)
+#define MPIORESETBOARD _IO('m',12)