diff -r 6f16c908bb5d sys/dev/disk/nata/ata-pci.c
--- a/sys/dev/disk/nata/ata-pci.c	Mon Oct 29 13:02:41 2007 +0000
+++ b/sys/dev/disk/nata/ata-pci.c	Sat Dec 08 20:32:18 2007 +0000
@@ -194,7 +194,6 @@ ata_pci_attach(device_t dev)
     else
 	ctlr->channels = 1;
     ctlr->allocate = ata_pci_allocate;
-    ctlr->dmainit = ata_pci_dmainit;
     ctlr->dev = dev;
 
     /* if needed try to enable busmastering */
@@ -210,6 +209,8 @@ ata_pci_attach(device_t dev)
 	ctlr->r_rid1 = ATA_BMADDR_RID;
 	ctlr->r_res1 = bus_alloc_resource_any(dev, ctlr->r_type1, &ctlr->r_rid1,
 					      RF_ACTIVE);
+	/* Only set a dma init function if the device actually supports it. */
+        ctlr->dmainit = ata_pci_dmainit;
     }
 
     if (ctlr->chipinit(dev))