driver.c

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/*
 * driver.c - device id matching, driver model, etc.
 *
 * Copyright 2002 Adam Belay <[email protected]>
 */

#include <linux/string.h>
#include <linux/list.h>
#include <linux/module.h>
#include <linux/ctype.h>
#include <linux/slab.h>
#include <linux/pnp.h>
#include "base.h"

static int compare_func(const char *ida, const char *idb)
{
    int i;

    /* we only need to compare the last 4 chars */
    for (i = 3; i < 7; i++) {
        if (ida[i] != 'X' &&
            idb[i] != 'X' && toupper(ida[i]) != toupper(idb[i]))
            return 0;
    }
    return 1;
}

int compare_pnp_id(struct pnp_id *pos, const char *id)
{
    if (!pos || !id || (strlen(id) != 7))
        return 0;
    if (memcmp(id, "ANYDEVS", 7) == 0)
        return 1;
    while (pos) {
        if (memcmp(pos->id, id, 3) == 0)
            if (compare_func(pos->id, id) == 1)
                return 1;
        pos = pos->next;
    }
    return 0;
}

static const struct pnp_device_id *match_device(struct pnp_driver *drv,
                        struct pnp_dev *dev)
{
    const struct pnp_device_id *drv_id = drv->id_table;

    if (!drv_id)
        return NULL;

    while (*drv_id->id) {
        if (compare_pnp_id(dev->id, drv_id->id))
            return drv_id;
        drv_id++;
    }
    return NULL;
}

int pnp_device_attach(struct pnp_dev *pnp_dev)
{
    spin_lock(&pnp_lock);
    if (pnp_dev->status != PNP_READY) {
        spin_unlock(&pnp_lock);
        return -EBUSY;
    }
    pnp_dev->status = PNP_ATTACHED;
    spin_unlock(&pnp_lock);
    return 0;
}

void pnp_device_detach(struct pnp_dev *pnp_dev)
{
    spin_lock(&pnp_lock);
    if (pnp_dev->status == PNP_ATTACHED)
        pnp_dev->status = PNP_READY;
    spin_unlock(&pnp_lock);
    pnp_disable_dev(pnp_dev);
}

static int pnp_device_probe(struct device *dev)
{
    int error;
    struct pnp_driver *pnp_drv;
    struct pnp_dev *pnp_dev;
    const struct pnp_device_id *dev_id = NULL;
    pnp_dev = to_pnp_dev(dev);
    pnp_drv = to_pnp_driver(dev->driver);

    error = pnp_device_attach(pnp_dev);
    if (error < 0)
        return error;

    if (pnp_dev->active == 0) {
        if (!(pnp_drv->flags & PNP_DRIVER_RES_DO_NOT_CHANGE)) {
            error = pnp_activate_dev(pnp_dev);
            if (error < 0)
                return error;
        }
    } else if ((pnp_drv->flags & PNP_DRIVER_RES_DISABLE)
           == PNP_DRIVER_RES_DISABLE) {
        error = pnp_disable_dev(pnp_dev);
        if (error < 0)
            return error;
    }
    error = 0;
    if (pnp_drv->probe) {
        dev_id = match_device(pnp_drv, pnp_dev);
        if (dev_id != NULL)
            error = pnp_drv->probe(pnp_dev, dev_id);
    }
    if (error >= 0) {
        pnp_dev->driver = pnp_drv;
        error = 0;
    } else
        goto fail;

    return error;

fail:
    pnp_device_detach(pnp_dev);
    return error;
}

static int pnp_device_remove(struct device *dev)
{
    struct pnp_dev *pnp_dev = to_pnp_dev(dev);
    struct pnp_driver *drv = pnp_dev->driver;

    if (drv) {
        if (drv->remove)
            drv->remove(pnp_dev);
        pnp_dev->driver = NULL;
    }
    pnp_device_detach(pnp_dev);
    return 0;
}

static void pnp_device_shutdown(struct device *dev)
{
    struct pnp_dev *pnp_dev = to_pnp_dev(dev);
    struct pnp_driver *drv = pnp_dev->driver;

    if (drv && drv->shutdown)
        drv->shutdown(pnp_dev);
}

static int pnp_bus_match(struct device *dev, struct device_driver *drv)
{
    struct pnp_dev *pnp_dev = to_pnp_dev(dev);
    struct pnp_driver *pnp_drv = to_pnp_driver(drv);

    if (match_device(pnp_drv, pnp_dev) == NULL)
        return 0;
    return 1;
}

static int pnp_bus_suspend(struct device *dev, pm_message_t state)
{
    struct pnp_dev *pnp_dev = to_pnp_dev(dev);
    struct pnp_driver *pnp_drv = pnp_dev->driver;
    int error;

    if (!pnp_drv)
        return 0;

    if (pnp_drv->suspend) {
        error = pnp_drv->suspend(pnp_dev, state);
        if (error)
            return error;
    }

    if (pnp_can_disable(pnp_dev)) {
        error = pnp_stop_dev(pnp_dev);
        if (error)
            return error;
    }

    if (pnp_dev->protocol->suspend)
        pnp_dev->protocol->suspend(pnp_dev, state);
    return 0;
}

static int pnp_bus_resume(struct device *dev)
{
    struct pnp_dev *pnp_dev = to_pnp_dev(dev);
    struct pnp_driver *pnp_drv = pnp_dev->driver;
    int error;

    if (!pnp_drv)
        return 0;

    if (pnp_dev->protocol->resume) {
        error = pnp_dev->protocol->resume(pnp_dev);
        if (error)
            return error;
    }

    if (pnp_can_write(pnp_dev)) {
        error = pnp_start_dev(pnp_dev);
        if (error)
            return error;
    }

    if (pnp_drv->resume) {
        error = pnp_drv->resume(pnp_dev);
        if (error)
            return error;
    }

    return 0;
}

struct bus_type pnp_bus_type = {
    .name    = "pnp",
    .match   = pnp_bus_match,
    .probe   = pnp_device_probe,
    .remove  = pnp_device_remove,
    .shutdown = pnp_device_shutdown,
    .suspend = pnp_bus_suspend,
    .resume  = pnp_bus_resume,
    .dev_attrs = pnp_interface_attrs,
};

int pnp_register_driver(struct pnp_driver *drv)
{
    drv->driver.name = drv->name;
    drv->driver.bus = &pnp_bus_type;

    return driver_register(&drv->driver);
}

void pnp_unregister_driver(struct pnp_driver *drv)
{
    driver_unregister(&drv->driver);
}

struct pnp_id *pnp_add_id(struct pnp_dev *dev, const char *id)
{
    struct pnp_id *dev_id, *ptr;

    dev_id = kzalloc(sizeof(struct pnp_id), GFP_KERNEL);
    if (!dev_id)
        return NULL;

    dev_id->id[0] = id[0];
    dev_id->id[1] = id[1];
    dev_id->id[2] = id[2];
    dev_id->id[3] = tolower(id[3]);
    dev_id->id[4] = tolower(id[4]);
    dev_id->id[5] = tolower(id[5]);
    dev_id->id[6] = tolower(id[6]);
    dev_id->id[7] = '\0';

    dev_id->next = NULL;
    ptr = dev->id;
    while (ptr && ptr->next)
        ptr = ptr->next;
    if (ptr)
        ptr->next = dev_id;
    else
        dev->id = dev_id;

    return dev_id;
}

EXPORT_SYMBOL(pnp_register_driver);
EXPORT_SYMBOL(pnp_unregister_driver);
EXPORT_SYMBOL(pnp_device_attach);
EXPORT_SYMBOL(pnp_device_detach);