drivers/pci/hotplug.c

   1 #include <linux/kernel.h>
   2 #include <linux/pci.h>
   3 #include <linux/module.h>
   4 #include "pci.h"
   5
   6 int pci_hotplug (struct device *dev, char **envp, int num_envp,
   7                  char *buffer, int buffer_size)
   8 {
   9         struct pci_dev *pdev;
  10         char *scratch;
  11         int i = 0;
  12         int length = 0;
  13
  14         if (!dev)
  15                 return -ENODEV;
  16
  17         pdev = to_pci_dev(dev);
  18         if (!pdev)
  19                 return -ENODEV;
  20
  21         scratch = buffer;
  22
  23         /* stuff we want to pass to /sbin/hotplug */
  24         envp[i++] = scratch;
  25         length += scnprintf (scratch, buffer_size - length, "PCI_CLASS=%04X",
  26                             pdev->class);
  27         if ((buffer_size - length <= 0) || (i >= num_envp))
  28                 return -ENOMEM;
  29         ++length;
  30         scratch += length;
  31
  32         envp[i++] = scratch;
  33         length += scnprintf (scratch, buffer_size - length, "PCI_ID=%04X:%04X",
  34                             pdev->vendor, pdev->device);
  35         if ((buffer_size - length <= 0) || (i >= num_envp))
  36                 return -ENOMEM;
  37         ++length;
  38         scratch += length;
  39
  40         envp[i++] = scratch;
  41         length += scnprintf (scratch, buffer_size - length,
  42                             "PCI_SUBSYS_ID=%04X:%04X", pdev->subsystem_vendor,
  43                             pdev->subsystem_device);
  44         if ((buffer_size - length <= 0) || (i >= num_envp))
  45                 return -ENOMEM;
  46         ++length;
  47         scratch += length;
  48
  49         envp[i++] = scratch;
  50         length += scnprintf (scratch, buffer_size - length, "PCI_SLOT_NAME=%s",
  51                             pci_name(pdev));
  52         if ((buffer_size - length <= 0) || (i >= num_envp))
  53                 return -ENOMEM;
  54
  55         envp[i] = NULL;
  56
  57         return 0;
  58 }
  59
  60 static int pci_visit_bus (struct pci_visit * fn, struct pci_bus_wrapped *wrapped_bus, struct pci_dev_wrapped *wrapped_parent)
  61 {
  62         struct list_head *ln;
  63         struct pci_dev *dev;
  64         struct pci_dev_wrapped wrapped_dev;
  65         int result = 0;
  66
  67         pr_debug("PCI: Scanning bus %04x:%02x\n", pci_domain_nr(wrapped_bus->bus),
  68                 wrapped_bus->bus->number);
  69
  70         if (fn->pre_visit_pci_bus) {
  71                 result = fn->pre_visit_pci_bus(wrapped_bus, wrapped_parent);
  72                 if (result)
  73                         return result;
  74         }
  75
  76         ln = wrapped_bus->bus->devices.next;
  77         while (ln != &wrapped_bus->bus->devices) {
  78                 dev = pci_dev_b(ln);
  79                 ln = ln->next;
  80
  81                 memset(&wrapped_dev, 0, sizeof(struct pci_dev_wrapped));
  82                 wrapped_dev.dev = dev;
  83
  84                 result = pci_visit_dev(fn, &wrapped_dev, wrapped_bus);
  85                 if (result)
  86                         return result;
  87         }
  88
  89         if (fn->post_visit_pci_bus)
  90                 result = fn->post_visit_pci_bus(wrapped_bus, wrapped_parent);
  91
  92         return result;
  93 }
  94
  95 static int pci_visit_bridge (struct pci_visit * fn,
  96                              struct pci_dev_wrapped *wrapped_dev,
  97                              struct pci_bus_wrapped *wrapped_parent)
  98 {
  99         struct pci_bus *bus;
 100         struct pci_bus_wrapped wrapped_bus;
 101         int result = 0;
 102
 103         pr_debug("PCI: Scanning bridge %s\n", pci_name(wrapped_dev->dev));
 104
 105         if (fn->visit_pci_dev) {
 106                 result = fn->visit_pci_dev(wrapped_dev, wrapped_parent);
 107                 if (result)
 108                         return result;
 109         }
 110
 111         bus = wrapped_dev->dev->subordinate;
 112         if (bus) {
 113                 memset(&wrapped_bus, 0, sizeof(struct pci_bus_wrapped));
 114                 wrapped_bus.bus = bus;
 115
 116                 result = pci_visit_bus(fn, &wrapped_bus, wrapped_dev);
 117         }
 118         return result;
 119 }
 120
 121 /**
 122  * pci_visit_dev - scans the pci buses.
 123  * Every bus and every function is presented to a custom
 124  * function that can act upon it.
 125  */
 126 int pci_visit_dev(struct pci_visit *fn, struct pci_dev_wrapped *wrapped_dev,
 127                   struct pci_bus_wrapped *wrapped_parent)
 128 {
 129         struct pci_dev* dev = wrapped_dev ? wrapped_dev->dev : NULL;
 130         int result = 0;
 131
 132         if (!dev)
 133                 return 0;
 134
 135         if (fn->pre_visit_pci_dev) {
 136                 result = fn->pre_visit_pci_dev(wrapped_dev, wrapped_parent);
 137                 if (result)
 138                         return result;
 139         }
 140
 141         switch (dev->class >> 8) {
 142                 case PCI_CLASS_BRIDGE_PCI:
 143                         result = pci_visit_bridge(fn, wrapped_dev,
 144                                                   wrapped_parent);
 145                         if (result)
 146                                 return result;
 147                         break;
 148                 default:
 149                         pr_debug("PCI: Scanning device %s\n", pci_name(dev));
 150                         if (fn->visit_pci_dev) {
 151                                 result = fn->visit_pci_dev (wrapped_dev,
 152                                                             wrapped_parent);
 153                                 if (result)
 154                                         return result;
 155                         }
 156         }
 157
 158         if (fn->post_visit_pci_dev)
 159                 result = fn->post_visit_pci_dev(wrapped_dev, wrapped_parent);
 160
 161         return result;
 162 }
 163 EXPORT_SYMBOL(pci_visit_dev);