[PATCH V4 1/2] PCI: pcibus address to resource converting take bus directly

[Gavin Shan]

For allocating resource under bus path, we do have dev pass along,
and we could just use bus instead. Also, we'd like to make function
find_pci_host_bridge() global so that some platforms (e.g. PPC) can
access the pci host bridge directly.

Signed-off-by: Yinghai Lu <yinghai at kernel.org>
---
 drivers/pci/host-bridge.c |   34 +++++++++++++++++++++-------------
 include/linux/pci.h       |    4 ++++
 2 files changed, 25 insertions(+), 13 deletions(-)

diff --git a/drivers/pci/host-bridge.c b/drivers/pci/host-bridge.c
index a68dc61..4ccf477 100644
--- a/drivers/pci/host-bridge.c
+++ b/drivers/pci/host-bridge.c
@@ -9,22 +9,19 @@
 
 #include "pci.h"
 
-static struct pci_bus *find_pci_root_bus(struct pci_dev *dev)
+static struct pci_bus *find_pci_root_bus(struct pci_bus *bus)
 {
-	struct pci_bus *bus;
-
-	bus = dev->bus;
 	while (bus->parent)
 		bus = bus->parent;
 
 	return bus;
 }
 
-static struct pci_host_bridge *find_pci_host_bridge(struct pci_dev *dev)
+struct pci_host_bridge *find_pci_host_bridge(struct pci_bus *bus)
 {
-	struct pci_bus *bus = find_pci_root_bus(dev);
+	struct pci_bus *root_bus = find_pci_root_bus(bus);
 
-	return to_pci_host_bridge(bus->bridge);
+	return to_pci_host_bridge(root_bus->bridge);
 }
 
 void pci_set_host_bridge_release(struct pci_host_bridge *bridge,
@@ -40,10 +37,11 @@ static bool resource_contains(struct resource *res1, struct resource *res2)
 	return res1->start <= res2->start && res1->end >= res2->end;
 }
 
-void pcibios_resource_to_bus(struct pci_dev *dev, struct pci_bus_region *region,
-			     struct resource *res)
+void __pcibios_resource_to_bus(struct pci_bus *bus,
+				      struct pci_bus_region *region,
+				      struct resource *res)
 {
-	struct pci_host_bridge *bridge = find_pci_host_bridge(dev);
+	struct pci_host_bridge *bridge = find_pci_host_bridge(bus);
 	struct pci_host_bridge_window *window;
 	resource_size_t offset = 0;
 
@@ -60,6 +58,11 @@ void pcibios_resource_to_bus(struct pci_dev *dev, struct pci_bus_region *region,
 	region->start = res->start - offset;
 	region->end = res->end - offset;
 }
+void pcibios_resource_to_bus(struct pci_dev *dev, struct pci_bus_region *region,
+			     struct resource *res)
+{
+	__pcibios_resource_to_bus(dev->bus, region, res);
+}
 EXPORT_SYMBOL(pcibios_resource_to_bus);
 
 static bool region_contains(struct pci_bus_region *region1,
@@ -68,10 +71,10 @@ static bool region_contains(struct pci_bus_region *region1,
 	return region1->start <= region2->start && region1->end >= region2->end;
 }
 
-void pcibios_bus_to_resource(struct pci_dev *dev, struct resource *res,
-			     struct pci_bus_region *region)
+static void __pcibios_bus_to_resource(struct pci_bus *bus, struct resource *res,
+				      struct pci_bus_region *region)
 {
-	struct pci_host_bridge *bridge = find_pci_host_bridge(dev);
+	struct pci_host_bridge *bridge = find_pci_host_bridge(bus);
 	struct pci_host_bridge_window *window;
 	resource_size_t offset = 0;
 
@@ -93,4 +96,9 @@ void pcibios_bus_to_resource(struct pci_dev *dev, struct resource *res,
 	res->start = region->start + offset;
 	res->end = region->end + offset;
 }
+void pcibios_bus_to_resource(struct pci_dev *dev, struct resource *res,
+			     struct pci_bus_region *region)
+{
+	__pcibios_bus_to_resource(dev->bus, res, region);
+}
 EXPORT_SYMBOL(pcibios_bus_to_resource);
diff --git a/include/linux/pci.h b/include/linux/pci.h
index fefb4e1..2b559f1 100644
--- a/include/linux/pci.h
+++ b/include/linux/pci.h
@@ -385,6 +385,7 @@ struct pci_host_bridge {
 };
 
 #define	to_pci_host_bridge(n) container_of(n, struct pci_host_bridge, dev)
+struct pci_host_bridge *find_pci_host_bridge(struct pci_bus *bus);
 void pci_set_host_bridge_release(struct pci_host_bridge *bridge,
 		     void (*release_fn)(struct pci_host_bridge *),
 		     void *release_data);
@@ -657,6 +658,9 @@ void pci_fixup_cardbus(struct pci_bus *);
 
 /* Generic PCI functions used internally */
 
+void __pcibios_resource_to_bus(struct pci_bus *bus,
+			       struct pci_bus_region *region,
+			       struct resource *res);
 void pcibios_resource_to_bus(struct pci_dev *dev, struct pci_bus_region *region,
 			     struct resource *res);
 void pcibios_bus_to_resource(struct pci_dev *dev, struct resource *res,
-- 
1.7.9.5