diff --git a/include/linux/ide.h b/include/linux/ide.h
index f1a10c8..1b31597 100644
--- a/include/linux/ide.h
+++ b/include/linux/ide.h
@@ -1093,6 +1093,8 @@
 	IDE_HFLAG_ABUSE_SET_DMA_MODE	= (1 << 26),
 	/* host is CY82C693 */
 	IDE_HFLAG_CY82C693		= (1 << 27),
+	/* force host out of "simplex" mode */
+	IDE_HFLAG_CLEAR_SIMPLEX		= (1 << 28),
 };
 
 #ifdef CONFIG_BLK_DEV_OFFBOARD