diff --git a/drivers/pci/pci.c b/drivers/pci/pci.c
index 1f5dc78..2762511 100644
--- a/drivers/pci/pci.c
+++ b/drivers/pci/pci.c
@@ -348,6 +348,12 @@
 			dev->rom_address = (l == 0xffffffff) ? 0 : l;
 
 			setup_device(dev, 6);
+			/*
+			 * If this device is on the root bus, there is no bridge
+			 * to configure, so we can activate it right away.
+			 */
+			if (!bus->parent_bus)
+				pci_register_device(dev);
 			break;
 		case PCI_HEADER_TYPE_BRIDGE:
 			setup_device(dev, 2);
@@ -356,6 +362,7 @@
 			/* inherit parent properties */
 			child_bus->host = bus->host;
 			child_bus->ops = bus->host->pci_ops;
+			child_bus->parent_bus = bus;
 			child_bus->resource[PCI_BUS_RESOURCE_MEM] =
 				bus->resource[PCI_BUS_RESOURCE_MEM];
 			child_bus->resource[PCI_BUS_RESOURCE_MEM_PREF] =
diff --git a/include/linux/pci.h b/include/linux/pci.h
index 3d0e73b..e422055 100644
--- a/include/linux/pci.h
+++ b/include/linux/pci.h
@@ -123,6 +123,7 @@
 struct pci_bus {
 	struct pci_controller *host;	/* associated host controller */
 	struct device_d *parent;
+	struct pci_bus *parent_bus;	/* parent bus */
 	struct list_head node;		/* node in list of buses */
 	struct list_head children;	/* list of child buses */
 	struct list_head devices;	/* list of devices on this bus */