diff --git a/include/linux/mISDNif.h b/include/linux/mISDNif.h
index 8f2d60d..74c903c 100644
--- a/include/linux/mISDNif.h
+++ b/include/linux/mISDNif.h
@@ -312,6 +312,7 @@
 #define MISDN_CTRL_SETPEER		0x0040
 #define MISDN_CTRL_UNSETPEER		0x0080
 #define MISDN_CTRL_RX_OFF		0x0100
+#define MISDN_CTRL_FILL_EMPTY		0x0200
 #define MISDN_CTRL_HW_FEATURES_OP	0x2000
 #define MISDN_CTRL_HW_FEATURES		0x2001
 #define MISDN_CTRL_HFC_OP		0x4000