conf_space_quirks.c

Go to the documentation of this file.

/*
 * PCI Backend - Handle special overlays for broken devices.
 *
 * Author: Ryan Wilson <[email protected]>
 * Author: Chris Bookholt <[email protected]>
 */

#include <linux/kernel.h>
#include <linux/pci.h>
#include "pciback.h"
#include "conf_space.h"
#include "conf_space_quirks.h"

LIST_HEAD(xen_pcibk_quirks);
static inline const struct pci_device_id *
match_one_device(const struct pci_device_id *id, const struct pci_dev *dev)
{
    if ((id->vendor == PCI_ANY_ID || id->vendor == dev->vendor) &&
        (id->device == PCI_ANY_ID || id->device == dev->device) &&
        (id->subvendor == PCI_ANY_ID ||
                id->subvendor == dev->subsystem_vendor) &&
        (id->subdevice == PCI_ANY_ID ||
                id->subdevice == dev->subsystem_device) &&
        !((id->class ^ dev->class) & id->class_mask))
        return id;
    return NULL;
}

static struct xen_pcibk_config_quirk *xen_pcibk_find_quirk(struct pci_dev *dev)
{
    struct xen_pcibk_config_quirk *tmp_quirk;

    list_for_each_entry(tmp_quirk, &xen_pcibk_quirks, quirks_list)
        if (match_one_device(&tmp_quirk->devid, dev) != NULL)
            goto out;
    tmp_quirk = NULL;
    printk(KERN_DEBUG DRV_NAME
           ": quirk didn't match any device known\n");
out:
    return tmp_quirk;
}

static inline void register_quirk(struct xen_pcibk_config_quirk *quirk)
{
    list_add_tail(&quirk->quirks_list, &xen_pcibk_quirks);
}

int xen_pcibk_field_is_dup(struct pci_dev *dev, unsigned int reg)
{
    int ret = 0;
    struct xen_pcibk_dev_data *dev_data = pci_get_drvdata(dev);
    struct config_field_entry *cfg_entry;

    list_for_each_entry(cfg_entry, &dev_data->config_fields, list) {
        if (OFFSET(cfg_entry) == reg) {
            ret = 1;
            break;
        }
    }
    return ret;
}

int xen_pcibk_config_quirks_add_field(struct pci_dev *dev, struct config_field
                    *field)
{
    int err = 0;

    switch (field->size) {
    case 1:
        field->u.b.read = xen_pcibk_read_config_byte;
        field->u.b.write = xen_pcibk_write_config_byte;
        break;
    case 2:
        field->u.w.read = xen_pcibk_read_config_word;
        field->u.w.write = xen_pcibk_write_config_word;
        break;
    case 4:
        field->u.dw.read = xen_pcibk_read_config_dword;
        field->u.dw.write = xen_pcibk_write_config_dword;
        break;
    default:
        err = -EINVAL;
        goto out;
    }

    xen_pcibk_config_add_field(dev, field);

out:
    return err;
}

int xen_pcibk_config_quirks_init(struct pci_dev *dev)
{
    struct xen_pcibk_config_quirk *quirk;
    int ret = 0;

    quirk = kzalloc(sizeof(*quirk), GFP_ATOMIC);
    if (!quirk) {
        ret = -ENOMEM;
        goto out;
    }

    quirk->devid.vendor = dev->vendor;
    quirk->devid.device = dev->device;
    quirk->devid.subvendor = dev->subsystem_vendor;
    quirk->devid.subdevice = dev->subsystem_device;
    quirk->devid.class = 0;
    quirk->devid.class_mask = 0;
    quirk->devid.driver_data = 0UL;

    quirk->pdev = dev;

    register_quirk(quirk);
out:
    return ret;
}

void xen_pcibk_config_field_free(struct config_field *field)
{
    kfree(field);
}

int xen_pcibk_config_quirk_release(struct pci_dev *dev)
{
    struct xen_pcibk_config_quirk *quirk;
    int ret = 0;

    quirk = xen_pcibk_find_quirk(dev);
    if (!quirk) {
        ret = -ENXIO;
        goto out;
    }

    list_del(&quirk->quirks_list);
    kfree(quirk);

out:
    return ret;
}