PCI: add host bridge release support

We need a hook to release host bridge resources allocated when creating
root bus.

Signed-off-by: Yinghai Lu <yinghai@kernel.org>
Signed-off-by: Bjorn Helgaas <bhelgaas@google.com>

drivers/pci/host-bridge.c

@@ -27,6 +27,14 @@ static struct pci_host_bridge *find_pci_host_bridge(struct pci_dev *dev)
 	return to_pci_host_bridge(bus->bridge);
 }
 
+void pci_set_host_bridge_release(struct pci_host_bridge *bridge,
+				 void (*release_fn)(struct pci_host_bridge *),
+				 void *release_data)
+{
+	bridge->release_fn = release_fn;
+	bridge->release_data = release_data;
+}
+
 static bool resource_contains(struct resource *res1, struct resource *res2)
 {
 	return res1->start <= res2->start && res1->end >= res2->end;

drivers/pci/probe.c

@@ -1137,7 +1137,8 @@ static void pci_release_bus_bridge_dev(struct device *dev)
 {
 	struct pci_host_bridge *bridge = to_pci_host_bridge(dev);
 
-	/* TODO: need to free window->res */
+	if (bridge->release_fn)
+		bridge->release_fn(bridge);
 
 	pci_free_resource_list(&bridge->windows);
 

include/linux/pci.h

@@ -378,9 +378,14 @@ struct pci_host_bridge {
 	struct device dev;
 	struct pci_bus *bus;		/* root bus */
 	struct list_head windows;	/* pci_host_bridge_windows */
+	void (*release_fn)(struct pci_host_bridge *);
+	void *release_data;
 };
 
 #define	to_pci_host_bridge(n) container_of(n, struct pci_host_bridge, dev)
+void pci_set_host_bridge_release(struct pci_host_bridge *bridge,
+		     void (*release_fn)(struct pci_host_bridge *),
+		     void *release_data);
 
 /*
  * The first PCI_BRIDGE_RESOURCE_NUM PCI bus resources (those that correspond