PCI: factor pci_bus_add_child() from pci_bus_add_devices()

This patch splits a new function, pci_bus_add_child(), from
pci_bus_add_devices(). The new function can be used to register PCI
buses to the device core.

Signed-off-by: Yu Zhao <[e-mail]>
Signed-off-by: Jesse Barnes <[e-mail]>

drivers/pci/bus.c

···
 }
 
 /**
+ * pci_bus_add_child - add a child bus
+ * @bus: bus to add
+ *
+ * This adds sysfs entries for a single bus
+ */
+int pci_bus_add_child(struct pci_bus *bus)
+{
+	int retval;
+
+	if (bus->bridge)
+		bus->dev.parent = bus->bridge;
+
+	retval = device_register(&bus->dev);
+	if (retval)
+		return retval;
+
+	bus->is_added = 1;
+
+	retval = device_create_file(&bus->dev, &dev_attr_cpuaffinity);
+	if (retval)
+		return retval;
+
+	retval = device_create_file(&bus->dev, &dev_attr_cpulistaffinity);
+
+	/* Create legacy_io and legacy_mem files for this bus */
+	pci_create_legacy_files(bus);
+
+	return retval;
+}
+
+/**
  * pci_bus_add_devices - insert newly discovered PCI devices
  * @bus: bus to check for new devices
  *
···
 		 */
 		if (child->is_added)
 			continue;
-		child->dev.parent = child->bridge;
-		retval = device_register(&child->dev);
+		retval = pci_bus_add_child(child);
 		if (retval)
-			dev_err(&dev->dev, "Error registering pci_bus,"
-				" continuing...\n");
-		else {
-			child->is_added = 1;
-			retval = device_create_file(&child->dev,
-						&dev_attr_cpuaffinity);
-			if (retval)
-				dev_err(&dev->dev, "Error creating cpuaffinity"
-					" file, continuing...\n");
-
-			retval = device_create_file(&child->dev,
-						&dev_attr_cpulistaffinity);
-			if (retval)
-				dev_err(&dev->dev,
-					"Error creating cpulistaffinity"
-					" file, continuing...\n");
-
-			/* Create legacy_io and legacy_mem files for this bus */
-			pci_create_legacy_files(child_bus);
-
-		}
+			dev_err(&dev->dev, "Error adding bus, continuing\n");
 	}
 }
 

drivers/pci/pci.h

···
 				struct resource *res, unsigned int reg);
 extern int pci_resource_bar(struct pci_dev *dev, int resno,
 			    enum pci_bar_type *type);
+extern int pci_bus_add_child(struct pci_bus *bus);
 extern void pci_enable_ari(struct pci_dev *dev);
 /**
  * pci_ari_enabled - query ARI forwarding status