diff --git a/sys/pci/if_tl.c b/sys/pci/if_tl.c
index c6d236928d5b..d778794b16ad 100644
--- a/sys/pci/if_tl.c
+++ b/sys/pci/if_tl.c
@@ -29,7 +29,7 @@
  * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF
  * THE POSSIBILITY OF SUCH DAMAGE.
  *
- *	$Id: if_tl.c,v 1.30 1998/09/24 16:26:02 wpaul Exp $
+ *	$Id: if_tl.c,v 1.16 1998/09/24 17:14:23 wpaul Exp $
  */
 
 /*
@@ -205,13 +205,20 @@
 #include <pci/pcireg.h>
 #include <pci/pcivar.h>
 
+/*
+ * Default to using PIO register access mode to pacify certain
+ * laptop docking stations with built-in ThunderLAN chips that
+ * don't seem to handle memory mapped mode properly.
+ */
+#define TL_USEIOSPACE
+
 /* #define TL_BACKGROUND_AUTONEG */
 
 #include <pci/if_tlreg.h>
 
 #ifndef lint
 static char rcsid[] =
-	"$Id: if_tl.c,v 1.30 1998/09/24 16:26:02 wpaul Exp $";
+	"$Id: if_tl.c,v 1.16 1998/09/24 17:14:23 wpaul Exp $";
 #endif
 
 #ifdef TL_DEBUG