2 files changed, 36 insertions, 0 deletions

diff --git a/drivers/pci/setup-bus.c b/drivers/pci/setup-bus.c
index 802f56be2149..e3e17f3c0f0f 100644
--- a/drivers/pci/setup-bus.c
+++ b/drivers/pci/setup-bus.c
@@ -646,6 +646,41 @@ void pci_setup_bridge(struct pci_bus *bus)
         __pci_setup_bridge(bus, type);
 }
 
+
+int pci_claim_bridge_resource(struct pci_dev *bridge, int i)
+{
+        if (i < PCI_BRIDGE_RESOURCES || i > PCI_BRIDGE_RESOURCE_END)
+                return 0;
+
+        if (pci_claim_resource(bridge, i) == 0)
+                return 0;       /* claimed the window */
+
+        if ((bridge->class >> 8) != PCI_CLASS_BRIDGE_PCI)
+                return 0;
+
+        if (!pci_bus_clip_resource(bridge, i))
+                return -EINVAL; /* clipping didn't change anything */
+
+        switch (i - PCI_BRIDGE_RESOURCES) {
+        case 0:
+                pci_setup_bridge_io(bridge);
+                break;
+        case 1:
+                pci_setup_bridge_mmio(bridge);
+                break;
+        case 2:
+                pci_setup_bridge_mmio_pref(bridge);
+                break;
+        default:
+                return -EINVAL;
+        }
+
+        if (pci_claim_resource(bridge, i) == 0)
+                return 0;       /* claimed a smaller window */
+
+        return -EINVAL;
+}
+
 /* Check whether the bridge supports optional I/O and
    prefetchable memory ranges. If not, the respective
    base/limit registers must be read-only and read as 0. */
diff --git a/include/linux/pci.h b/include/linux/pci.h
index 44627f1df4ca..9603094ed59b 100644
--- a/include/linux/pci.h
+++ b/include/linux/pci.h
@@ -1067,6 +1067,7 @@ resource_size_t pcibios_retrieve_fw_addr(struct pci_dev *dev, int idx);
 void pci_bus_assign_resources(const struct pci_bus *bus);
 void pci_bus_size_bridges(struct pci_bus *bus);
 int pci_claim_resource(struct pci_dev *, int);
+int pci_claim_bridge_resource(struct pci_dev *bridge, int i);
 void pci_assign_unassigned_resources(void);
 void pci_assign_unassigned_bridge_resources(struct pci_dev *bridge);
 void pci_assign_unassigned_bus_resources(struct pci_bus *bus);