drivers/pci/of.c

   1 /*
   2  * PCI <-> OF mapping helpers
   3  *
   4  * Copyright 2011 IBM Corp.
   5  *
   6  * This program is free software; you can redistribute it and/or
   7  * modify it under the terms of the GNU General Public License
   8  * as published by the Free Software Foundation; either version
   9  * 2 of the License, or (at your option) any later version.
  10  */
  11
  12 #include <linux/kernel.h>
  13 #include <linux/pci.h>
  14 #include <linux/of.h>
  15 #include <linux/of_pci.h>
  16 #include "pci.h"
  17
  18 void pci_set_of_node(struct pci_dev *dev)
  19 {
  20         if (!dev->bus->dev.of_node)
  21                 return;
  22         dev->dev.of_node = of_pci_find_child_device(dev->bus->dev.of_node,
  23                                                     dev->devfn);
  24 }
  25
  26 void pci_release_of_node(struct pci_dev *dev)
  27 {
  28         of_node_put(dev->dev.of_node);
  29         dev->dev.of_node = NULL;
  30 }
  31
  32 void pci_set_bus_of_node(struct pci_bus *bus)
  33 {
  34         if (bus->self == NULL)
  35                 bus->dev.of_node = pcibios_get_phb_of_node(bus);
  36         else
  37                 bus->dev.of_node = of_node_get(bus->self->dev.of_node);
  38 }
  39
  40 void pci_release_bus_of_node(struct pci_bus *bus)
  41 {
  42         of_node_put(bus->dev.of_node);
  43         bus->dev.of_node = NULL;
  44 }
  45
  46 struct device_node * __weak pcibios_get_phb_of_node(struct pci_bus *bus)
  47 {
  48         /* This should only be called for PHBs */
  49         if (WARN_ON(bus->self || bus->parent))
  50                 return NULL;
  51
  52         /* Look for a node pointer in either the intermediary device we
  53          * create above the root bus or it's own parent. Normally only
  54          * the later is populated.
  55          */
  56         if (bus->bridge->of_node)
  57                 return of_node_get(bus->bridge->of_node);
  58         if (bus->bridge->parent && bus->bridge->parent->of_node)
  59                 return of_node_get(bus->bridge->parent->of_node);
  60         return NULL;
  61 }