diff --git a/sys/dev/ata/ata_wdc.c b/sys/dev/ata/ata_wdc.c
index 33c730d19ceb..cf05794e6ff8 100644
--- a/sys/dev/ata/ata_wdc.c
+++ b/sys/dev/ata/ata_wdc.c
@@ -1,4 +1,4 @@
-/*	$NetBSD: ata_wdc.c,v 1.5 1998/10/13 15:02:41 bouyer Exp $	*/
+/*	$NetBSD: ata_wdc.c,v 1.6 1998/10/13 15:18:46 bouyer Exp $	*/
 
 /*
  * Copyright (c) 1998 Manuel Bouyer.
@@ -586,6 +586,9 @@ again:
 		/* Don't try to set modes if controller can't be adjusted */
 		if ((chp->wdc->cap & WDC_CAPABILITY_MODE) == 0)
 			goto geometry;
+		/* Also don't try if the drive didn't report its mode */
+		if ((drvp->drive_flags & DRIVE_MODE) == 0)
+			goto geometry;
 		wdccommand(chp, drvp->drive, SET_FEATURES, 0, 0, 0,
 		    0x08 | drvp->PIO_mode, WDSF_SET_MODE);
 		drvp->state = PIOMODE_WAIT;
diff --git a/sys/dev/ata/atavar.h b/sys/dev/ata/atavar.h
index bc2bcf33c9b1..1a0396426f90 100644
--- a/sys/dev/ata/atavar.h
+++ b/sys/dev/ata/atavar.h
@@ -1,4 +1,4 @@
-/*	$NetBSD: atavar.h,v 1.2 1998/10/12 16:09:15 bouyer Exp $	*/
+/*	$NetBSD: atavar.h,v 1.3 1998/10/13 15:18:47 bouyer Exp $	*/
 
 /*
  * Copyright (c) 1998 Manuel Bouyer.
@@ -45,6 +45,7 @@ struct ata_drive_datas {
 #define DRIVE_CAP32 0x04
 #define DRIVE_DMA   0x08
 #define DRIVE_UDMA  0x10
+#define DRIVE_MODE 0x20 /* the drive reported its mode */
     /*
      * Current setting of drive's PIO, DMA and UDMA modes.
      * Is initialised by the disks drivers at attach time, and may be
diff --git a/sys/dev/ic/wdc.c b/sys/dev/ic/wdc.c
index 1b84201b206b..71662546a638 100644
--- a/sys/dev/ic/wdc.c
+++ b/sys/dev/ic/wdc.c
@@ -1,4 +1,4 @@
-/*	$NetBSD: wdc.c,v 1.34 1998/10/13 15:02:42 bouyer Exp $ */
+/*	$NetBSD: wdc.c,v 1.35 1998/10/13 15:18:47 bouyer Exp $ */
 
 
 /*
@@ -770,6 +770,7 @@ wdc_probe_caps(drvp)
 			printf("\n");
 			return;
 		}
+		drvp->drive_flags |= DRIVE_MODE;
 		printed = 0;
 		for (i = 7; i >= 0; i--) {
 			if ((params.atap_dmamode_supp & (1 << i)) == 0)
diff --git a/sys/dev/scsipi/atapi_wdc.c b/sys/dev/scsipi/atapi_wdc.c
index dee2c6caab06..5e82ee493674 100644
--- a/sys/dev/scsipi/atapi_wdc.c
+++ b/sys/dev/scsipi/atapi_wdc.c
@@ -1,4 +1,4 @@
-/*	$NetBSD: atapi_wdc.c,v 1.5 1998/10/13 15:02:43 bouyer Exp $	*/
+/*	$NetBSD: atapi_wdc.c,v 1.6 1998/10/13 15:18:48 bouyer Exp $	*/
 
 /*
  * Copyright (c) 1998 Manuel Bouyer.
@@ -607,6 +607,9 @@ again:
 		/* Don't try to set mode if controller can't be adjusted */
 		if ((chp->wdc->cap & WDC_CAPABILITY_MODE) == 0)
 			goto ready;
+		/* Also don't try if the drive didn't report its mode */
+		if ((drvp->drive_flags & DRIVE_MODE) == 0)
+			goto ready;;
 		wdccommand(chp, drvp->drive, SET_FEATURES, 0, 0, 0,
 		    0x08 | drvp->PIO_mode, WDSF_SET_MODE);
 		drvp->state = PIOMODE_WAIT;