diff --git a/drivers/ide/pci/hpt366.c b/drivers/ide/pci/hpt366.c
index c929dad..397c6cb 100644
--- a/drivers/ide/pci/hpt366.c
+++ b/drivers/ide/pci/hpt366.c
@@ -759,8 +759,7 @@
 				enable_irq (hwif->irq);
 		}
 	} else
-		outb(mask ? (drive->ctl | 2) : (drive->ctl & ~2),
-		     hwif->io_ports.ctl_addr);
+		outb(ATA_DEVCTL_OBS | (mask ? 2 : 0), hwif->io_ports.ctl_addr);
 }
 
 /*
diff --git a/drivers/ide/pci/ns87415.c b/drivers/ide/pci/ns87415.c
index a7a41bb..45ba71a 100644
--- a/drivers/ide/pci/ns87415.c
+++ b/drivers/ide/pci/ns87415.c
@@ -76,7 +76,7 @@
 	}
 
 	/* be sure we're looking at the low order bits */
-	outb(drive->ctl & ~0x80, io_ports->ctl_addr);
+	outb(ATA_DEVCTL_OBS & ~0x80, io_ports->ctl_addr);
 
 	if (task->tf_flags & IDE_TFLAG_IN_NSECT)
 		tf->nsect  = inb(io_ports->nsect_addr);
@@ -90,7 +90,7 @@
 		tf->device = superio_ide_inb(io_ports->device_addr);
 
 	if (task->tf_flags & IDE_TFLAG_LBA48) {
-		outb(drive->ctl | 0x80, io_ports->ctl_addr);
+		outb(ATA_DEVCTL_OBS | 0x80, io_ports->ctl_addr);
 
 		if (task->tf_flags & IDE_TFLAG_IN_HOB_FEATURE)
 			tf->hob_feature = inb(io_ports->feature_addr);
diff --git a/drivers/ide/pci/scc_pata.c b/drivers/ide/pci/scc_pata.c
index 32eb087..1584ebb 100644
--- a/drivers/ide/pci/scc_pata.c
+++ b/drivers/ide/pci/scc_pata.c
@@ -703,7 +703,7 @@
 	}
 
 	/* be sure we're looking at the low order bits */
-	scc_ide_outb(drive->ctl & ~0x80, io_ports->ctl_addr);
+	scc_ide_outb(ATA_DEVCTL_OBS & ~0x80, io_ports->ctl_addr);
 
 	if (task->tf_flags & IDE_TFLAG_IN_NSECT)
 		tf->nsect  = scc_ide_inb(io_ports->nsect_addr);
@@ -717,7 +717,7 @@
 		tf->device = scc_ide_inb(io_ports->device_addr);
 
 	if (task->tf_flags & IDE_TFLAG_LBA48) {
-		scc_ide_outb(drive->ctl | 0x80, io_ports->ctl_addr);
+		scc_ide_outb(ATA_DEVCTL_OBS | 0x80, io_ports->ctl_addr);
 
 		if (task->tf_flags & IDE_TFLAG_IN_HOB_FEATURE)
 			tf->hob_feature = scc_ide_inb(io_ports->feature_addr);
diff --git a/drivers/ide/pci/sgiioc4.c b/drivers/ide/pci/sgiioc4.c
index c1b667c..24513e3d 100644
--- a/drivers/ide/pci/sgiioc4.c
+++ b/drivers/ide/pci/sgiioc4.c
@@ -111,7 +111,7 @@
 static void
 sgiioc4_maskproc(ide_drive_t * drive, int mask)
 {
-	writeb(mask ? (drive->ctl | 2) : (drive->ctl & ~2),
+	writeb(ATA_DEVCTL_OBS | (mask ? 2 : 0),
 	       (void __iomem *)drive->hwif->io_ports.ctl_addr);
 }