drivers/xen/pciback/conf_space_quirks.c

   1 /*
   2  * PCI Backend - Handle special overlays for broken devices.
   3  *
   4  * Author: Ryan Wilson <hap9@epoch.ncsc.mil>
   5  * Author: Chris Bookholt <hap10@epoch.ncsc.mil>
   6  */
   7
   8 #include <linux/kernel.h>
   9 #include <linux/pci.h>
  10 #include "pciback.h"
  11 #include "conf_space.h"
  12 #include "conf_space_quirks.h"
  13
  14 LIST_HEAD(pciback_quirks);
  15
  16 struct pciback_config_quirk *pciback_find_quirk(struct pci_dev *dev)
  17 {
  18         struct pciback_config_quirk *tmp_quirk;
  19
  20         list_for_each_entry(tmp_quirk, &pciback_quirks, quirks_list)
  21             if (pci_match_id(&tmp_quirk->devid, dev))
  22                 goto out;
  23         tmp_quirk = NULL;
  24         printk(KERN_DEBUG
  25                "quirk didn't match any device pciback knows about\n");
  26       out:
  27         return tmp_quirk;
  28 }
  29
  30 static inline void register_quirk(struct pciback_config_quirk *quirk)
  31 {
  32         list_add_tail(&quirk->quirks_list, &pciback_quirks);
  33 }
  34
  35 int pciback_field_is_dup(struct pci_dev *dev, int reg)
  36 {
  37         int ret = 0;
  38         struct pciback_dev_data *dev_data = pci_get_drvdata(dev);
  39         struct config_field *field;
  40         struct config_field_entry *cfg_entry;
  41
  42         list_for_each_entry(cfg_entry, &dev_data->config_fields, list) {
  43                 field = cfg_entry->field;
  44                 if (field->offset == reg) {
  45                         ret = 1;
  46                         break;
  47                 }
  48         }
  49         return ret;
  50 }
  51
  52 int pciback_config_quirks_add_field(struct pci_dev *dev, struct config_field
  53                                     *field)
  54 {
  55         int err = 0;
  56
  57         switch (field->size) {
  58         case 1:
  59                 field->u.b.read = pciback_read_config_byte;
  60                 field->u.b.write = pciback_write_config_byte;
  61                 break;
  62         case 2:
  63                 field->u.w.read = pciback_read_config_word;
  64                 field->u.w.write = pciback_write_config_word;
  65                 break;
  66         case 4:
  67                 field->u.dw.read = pciback_read_config_dword;
  68                 field->u.dw.write = pciback_write_config_dword;
  69                 break;
  70         default:
  71                 err = -EINVAL;
  72                 goto out;
  73         }
  74
  75         pciback_config_add_field(dev, field);
  76
  77       out:
  78         return err;
  79 }
  80
  81 int pciback_config_quirks_init(struct pci_dev *dev)
  82 {
  83         struct pciback_config_quirk *quirk;
  84         int ret = 0;
  85
  86         quirk = kzalloc(sizeof(*quirk), GFP_ATOMIC);
  87         if (!quirk) {
  88                 ret = -ENOMEM;
  89                 goto out;
  90         }
  91
  92         quirk->devid.vendor = dev->vendor;
  93         quirk->devid.device = dev->device;
  94         quirk->devid.subvendor = dev->subsystem_vendor;
  95         quirk->devid.subdevice = dev->subsystem_device;
  96         quirk->devid.class = 0;
  97         quirk->devid.class_mask = 0;
  98         quirk->devid.driver_data = 0UL;
  99
 100         quirk->pdev = dev;
 101
 102         register_quirk(quirk);
 103       out:
 104         return ret;
 105 }
 106
 107 void pciback_config_field_free(struct config_field *field)
 108 {
 109         kfree(field);
 110 }
 111
 112 int pciback_config_quirk_release(struct pci_dev *dev)
 113 {
 114         struct pciback_config_quirk *quirk;
 115         int ret = 0;
 116
 117         quirk = pciback_find_quirk(dev);
 118         if (!quirk) {
 119                 ret = -ENXIO;
 120                 goto out;
 121         }
 122
 123         list_del(&quirk->quirks_list);
 124         kfree(quirk);
 125
 126       out:
 127         return ret;
 128 }