diff --git a/drivers/pci/pci.c b/drivers/pci/pci.c
index eb431b5c3685..b9a783385eae 100644
--- a/drivers/pci/pci.c
+++ b/drivers/pci/pci.c
@@ -4941,7 +4941,7 @@ int pci_get_new_domain_nr(void)
 }
 
 #ifdef CONFIG_PCI_DOMAINS_GENERIC
-void pci_bus_assign_domain_nr(struct pci_bus *bus, struct device *parent)
+int pci_bus_find_domain_nr(struct pci_bus *bus, struct device *parent)
 {
 	static int use_dt_domains = -1;
 	int domain = -1;
@@ -4985,7 +4985,7 @@ void pci_bus_assign_domain_nr(struct pci_bus *bus, struct device *parent)
 		domain = -1;
 	}
 
-	bus->domain_nr = domain;
+	return domain;
 }
 #endif
 #endif
diff --git a/drivers/pci/probe.c b/drivers/pci/probe.c
index 8e3ef720997d..380d46dc9a70 100644
--- a/drivers/pci/probe.c
+++ b/drivers/pci/probe.c
@@ -2127,7 +2127,9 @@ struct pci_bus *pci_create_root_bus(struct device *parent, int bus,
 	b->sysdata = sysdata;
 	b->ops = ops;
 	b->number = b->busn_res.start = bus;
-	pci_bus_assign_domain_nr(b, parent);
+#ifdef CONFIG_PCI_DOMAINS_GENERIC
+	b->domain_nr = pci_bus_find_domain_nr(b, parent);
+#endif
 	b2 = pci_find_bus(pci_domain_nr(b), bus);
 	if (b2) {
 		/* If we already got to this bus through a different bridge, ignore it */
diff --git a/include/linux/pci.h b/include/linux/pci.h
index ce03d650279b..48839e817ef2 100644
--- a/include/linux/pci.h
+++ b/include/linux/pci.h
@@ -1390,12 +1390,7 @@ static inline int pci_domain_nr(struct pci_bus *bus)
 {
 	return bus->domain_nr;
 }
-void pci_bus_assign_domain_nr(struct pci_bus *bus, struct device *parent);
-#else
-static inline void pci_bus_assign_domain_nr(struct pci_bus *bus,
-					struct device *parent)
-{
-}
+int pci_bus_find_domain_nr(struct pci_bus *bus, struct device *parent);
 #endif
 
 /* some architectures require additional setup to direct VGA traffic */