diff --git a/drivers/pci/pci.h b/drivers/pci/pci.h
index 4723b12..601abdc8 100644
--- a/drivers/pci/pci.h
+++ b/drivers/pci/pci.h
@@ -1,3 +1,9 @@
+#ifndef DRIVERS_PCI_H
+#define DRIVERS_PCI_H
+
+#define PCI_CFG_SPACE_SIZE	256
+#define PCI_CFG_SPACE_EXP_SIZE	4096
+
 /* Functions internal to the PCI core code */
 
 extern int pci_uevent(struct device *dev, struct kobj_uevent_env *env);
@@ -145,3 +151,4 @@
 };
 #define to_pci_slot_attr(s) container_of(s, struct pci_slot_attribute, attr)
 
+#endif /* DRIVERS_PCI_H */