/*
 * cs.c -- Kernel Card Services - core services
 *
 * This program is free software; you can redistribute it and/or modify
 * it under the terms of the GNU General Public License version 2 as
 * published by the Free Software Foundation.
 *
 * The initial developer of the original code is David A. Hinds
 * <dahinds@users.sourceforge.net>.  Portions created by David A. Hinds
 * are Copyright (C) 1999 David A. Hinds.  All Rights Reserved.
 *
 * (C) 1999             David A. Hinds
 */

#include <linux/module.h>
#include <linux/moduleparam.h>
#include <linux/init.h>
#include <linux/kernel.h>
#include <linux/string.h>
#include <linux/major.h>
#include <linux/errno.h>
#include <linux/slab.h>
#include <linux/mm.h>
#include <linux/interrupt.h>
#include <linux/timer.h>
#include <linux/ioport.h>
#include <linux/delay.h>
#include <linux/pm.h>
#include <linux/device.h>
#include <linux/kthread.h>
#include <linux/freezer.h>
#include <asm/irq.h>

#include <pcmcia/ss.h>
#include <pcmcia/cistpl.h>
#include <pcmcia/cisreg.h>
#include <pcmcia/ds.h>
#include "cs_internal.h"


/* Module parameters */

MODULE_AUTHOR("David Hinds <dahinds@users.sourceforge.net>");
MODULE_DESCRIPTION("Linux Kernel Card Services");
MODULE_LICENSE("GPL");

#define INT_MODULE_PARM(n, v) static int n = v; module_param(n, int, 0444)

INT_MODULE_PARM(setup_delay,    10);            /* centiseconds */
INT_MODULE_PARM(resume_delay,   20);            /* centiseconds */
INT_MODULE_PARM(shutdown_delay, 3);             /* centiseconds */
INT_MODULE_PARM(vcc_settle,     40);            /* centiseconds */
INT_MODULE_PARM(reset_time,     10);            /* usecs */
INT_MODULE_PARM(unreset_delay,  10);            /* centiseconds */
INT_MODULE_PARM(unreset_check,  10);            /* centiseconds */
INT_MODULE_PARM(unreset_limit,  30);            /* unreset_check's */

/* Access speed for attribute memory windows */
INT_MODULE_PARM(cis_speed,      300);           /* ns */


socket_state_t dead_socket = {
        .csc_mask       = SS_DETECT,
};
EXPORT_SYMBOL(dead_socket);


/* List of all sockets, protected by a rwsem */
LIST_HEAD(pcmcia_socket_list);
EXPORT_SYMBOL(pcmcia_socket_list);

DECLARE_RWSEM(pcmcia_socket_list_rwsem);
EXPORT_SYMBOL(pcmcia_socket_list_rwsem);


struct pcmcia_socket *pcmcia_get_socket(struct pcmcia_socket *skt)
{
        struct device *dev = get_device(&skt->dev);
        if (!dev)
                return NULL;
        return dev_get_drvdata(dev);
}
EXPORT_SYMBOL(pcmcia_get_socket);


void pcmcia_put_socket(struct pcmcia_socket *skt)
{
        put_device(&skt->dev);
}
EXPORT_SYMBOL(pcmcia_put_socket);


static void pcmcia_release_socket(struct device *dev)
{
        struct pcmcia_socket *socket = dev_get_drvdata(dev);

        complete(&socket->socket_released);
}

static int pccardd(void *__skt);

/**
 * pcmcia_register_socket - add a new pcmcia socket device
 * @socket: the &socket to register
 */
int pcmcia_register_socket(struct pcmcia_socket *socket)
{
        struct task_struct *tsk;
        int ret;

        if (!socket || !socket->ops || !socket->dev.parent || !socket->resource_ops)
                return -EINVAL;

        dev_dbg(&socket->dev, "pcmcia_register_socket(0x%p)\n", socket->ops);

        /* try to obtain a socket number [yes, it gets ugly if we
         * register more than 2^sizeof(unsigned int) pcmcia
         * sockets... but the socket number is deprecated
         * anyways, so I don't care] */
        down_write(&pcmcia_socket_list_rwsem);
        if (list_empty(&pcmcia_socket_list))
                socket->sock = 0;
        else {
                unsigned int found, i = 1;
                struct pcmcia_socket *tmp;
                do {
                        found = 1;
                        list_for_each_entry(tmp, &pcmcia_socket_list, socket_list) {
                                if (tmp->sock == i)
                                        found = 0;
                        }
                        i++;
                } while (!found);
                socket->sock = i - 1;
        }
        list_add_tail(&socket->socket_list, &pcmcia_socket_list);
        up_write(&pcmcia_socket_list_rwsem);

#ifndef CONFIG_CARDBUS
        /*
         * If we do not support Cardbus, ensure that
         * the Cardbus socket capability is disabled.
         */
        socket->features &= ~SS_CAP_CARDBUS;
#endif

        /* set proper values in socket->dev */
        dev_set_drvdata(&socket->dev, socket);
        socket->dev.class = &pcmcia_socket_class;
        dev_set_name(&socket->dev, "pcmcia_socket%u", socket->sock);

        /* base address = 0, map = 0 */
        socket->cis_mem.flags = 0;
        socket->cis_mem.speed = cis_speed;

        INIT_LIST_HEAD(&socket->cis_cache);

        init_completion(&socket->socket_released);
        init_completion(&socket->thread_done);
        mutex_init(&socket->skt_mutex);
        mutex_init(&socket->ops_mutex);
        spin_lock_init(&socket->thread_lock);

        if (socket->resource_ops->init) {
                mutex_lock(&socket->ops_mutex);
                ret = socket->resource_ops->init(socket);
                mutex_unlock(&socket->ops_mutex);
                if (ret)
                        goto err;
        }

        tsk = kthread_run(pccardd, socket, "pccardd");
        if (IS_ERR(tsk)) {
                ret = PTR_ERR(tsk);
                goto err;
        }

        wait_for_completion(&socket->thread_done);
        if (!socket->thread) {
                dev_printk(KERN_WARNING, &socket->dev,
                           "PCMCIA: warning: socket thread did not start\n");
                return -EIO;
        }

        pcmcia_parse_events(socket, SS_DETECT);

        /*
         * Let's try to get the PCMCIA module for 16-bit PCMCIA support.
         * If it fails, it doesn't matter -- we still have 32-bit CardBus
         * support to offer, so this is not a failure mode.
         */
        request_module_nowait("pcmcia");

        return 0;

 err:
        down_write(&pcmcia_socket_list_rwsem);
        list_del(&socket->socket_list);
        up_write(&pcmcia_socket_list_rwsem);
        return ret;
} /* pcmcia_register_socket */
EXPORT_SYMBOL(pcmcia_register_socket);


/**
 * pcmcia_unregister_socket - remove a pcmcia socket device
 * @socket: the &socket to unregister
 */
void pcmcia_unregister_socket(struct pcmcia_socket *socket)
{
        if (!socket)
                return;

        dev_dbg(&socket->dev, "pcmcia_unregister_socket(0x%p)\n", socket->ops);

        if (socket->thread)
                kthread_stop(socket->thread);

        /* remove from our own list */
        down_write(&pcmcia_socket_list_rwsem);
        list_del(&socket->socket_list);
        up_write(&pcmcia_socket_list_rwsem);

        /* wait for sysfs to drop all references */
        if (socket->resource_ops->exit) {
                mutex_lock(&socket->ops_mutex);
                socket->resource_ops->exit(socket);
                mutex_unlock(&socket->ops_mutex);
        }
        wait_for_completion(&socket->socket_released);
} /* pcmcia_unregister_socket */
EXPORT_SYMBOL(pcmcia_unregister_socket);


struct pcmcia_socket *pcmcia_get_socket_by_nr(unsigned int nr)
{
        struct pcmcia_socket *s;

        down_read(&pcmcia_socket_list_rwsem);
        list_for_each_entry(s, &pcmcia_socket_list, socket_list)
                if (s->sock == nr) {
                        up_read(&pcmcia_socket_list_rwsem);
                        return s;
                }
        up_read(&pcmcia_socket_list_rwsem);

        return NULL;

}
EXPORT_SYMBOL(pcmcia_get_socket_by_nr);

static int socket_reset(struct pcmcia_socket *skt)
{
        int status, i;

        dev_dbg(&skt->dev, "reset\n");

        skt->socket.flags |= SS_OUTPUT_ENA | SS_RESET;
        skt->ops->set_socket(skt, &skt->socket);
        udelay((long)reset_time);

        skt->socket.flags &= ~SS_RESET;
        skt->ops->set_socket(skt, &skt->socket);

        msleep(unreset_delay * 10);
        for (i = 0; i < unreset_limit; i++) {
                skt->ops->get_status(skt, &status);

                if (!(status & SS_DETECT))
                        return -ENODEV;

                if (status & SS_READY)
                        return 0;

                msleep(unreset_check * 10);
        }

        dev_printk(KERN_ERR, &skt->dev, "time out after reset.\n");
        return -ETIMEDOUT;
}

/*
 * socket_setup() and socket_shutdown() are called by the main event handler
 * when card insertion and removal events are received.
 * socket_setup() turns on socket power and resets the socket, in two stages.
 * socket_shutdown() unconfigures a socket and turns off socket power.
 */
static void socket_shutdown(struct pcmcia_socket *s)
{
        int status;

        dev_dbg(&s->dev, "shutdown\n");

        if (s->callback)
                s->callback->remove(s);

        mutex_lock(&s->ops_mutex);
        s->state &= SOCKET_INUSE | SOCKET_PRESENT;
        msleep(shutdown_delay * 10);
        s->state &= SOCKET_INUSE;

        /* Blank out the socket state */
        s->socket = dead_socket;
        s->ops->init(s);
        s->ops->set_socket(s, &s->socket);
        s->lock_count = 0;
        kfree(s->fake_cis);
        s->fake_cis = NULL;
        s->functions = 0;

        /* From here on we can be sure that only we (that is, the
         * pccardd thread) accesses this socket, and all (16-bit)
         * PCMCIA interactions are gone. Therefore, release
         * ops_mutex so that we don't get a sysfs-related lockdep
         * warning.
         */
        mutex_unlock(&s->ops_mutex);

#ifdef CONFIG_CARDBUS
        cb_free(s);
#endif

        /* give socket some time to power down */
        msleep(100);

        s->ops->get_status(s, &status);
        if (status & SS_POWERON) {
                dev_printk(KERN_ERR, &s->dev,
                           "*** DANGER *** unable to remove socket power\n");
        }

        s->state &= ~SOCKET_INUSE;
}

static int socket_setup(struct pcmcia_socket *skt, int initial_delay)
{
        int status, i;

        dev_dbg(&skt->dev, "setup\n");

        skt->ops->get_status(skt, &status);
        if (!(status & SS_DETECT))
                return -ENODEV;

        msleep(initial_delay * 10);

        for (i = 0; i < 100; i++) {
                skt->ops->get_status(skt, &status);
                if (!(status & SS_DETECT))
                        return -ENODEV;

                if (!(status & SS_PENDING))
                        break;

                msleep(100);
        }

        if (status & SS_PENDING) {
                dev_printk(KERN_ERR, &skt->dev,
                           "voltage interrogation timed out.\n");
                return -ETIMEDOUT;
        }

        if (status & SS_CARDBUS) {
                if (!(skt->features & SS_CAP_CARDBUS)) {
                        dev_printk(KERN_ERR, &skt->dev,
                                "cardbus cards are not supported.\n");
                        return -EINVAL;
                }
                skt->state |= SOCKET_CARDBUS;
        } else
                skt->state &= ~SOCKET_CARDBUS;

        /*
         * Decode the card voltage requirements, and apply power to the card.
         */
        if (status & SS_3VCARD)
                skt->socket.Vcc = skt->socket.Vpp = 33;
        else if (!(status & SS_XVCARD))
                skt->socket.Vcc = skt->socket.Vpp = 50;
        else {
                dev_printk(KERN_ERR, &skt->dev, "unsupported voltage key.\n");
                return -EIO;
        }

        if (skt->power_hook)
                skt->power_hook(skt, HOOK_POWER_PRE);

        skt->socket.flags = 0;
        skt->ops->set_socket(skt, &skt->socket);

        /*
         * Wait "vcc_settle" for the supply to stabilise.
         */
        msleep(vcc_settle * 10);

        skt->ops->get_status(skt, &status);
        if (!(status & SS_POWERON)) {
                dev_printk(KERN_ERR, &skt->dev, "unable to apply power.\n");
                return -EIO;
        }

        status = socket_reset(skt);

        if (skt->power_hook)
                skt->power_hook(skt, HOOK_POWER_POST);

        return status;
}

/*
 * Handle card insertion.  Setup the socket, reset the card,
 * and then tell the rest of PCMCIA that a card is present.
 */
static int socket_insert(struct pcmcia_socket *skt)
{
        int ret;

        dev_dbg(&skt->dev, "insert\n");

        mutex_lock(&skt->ops_mutex);
        if (skt->state & SOCKET_INUSE) {
                mutex_unlock(&skt->ops_mutex);
                return -EINVAL;
        }
        skt->state |= SOCKET_INUSE;

        ret = socket_setup(skt, setup_delay);
        if (ret == 0) {
                skt->state |= SOCKET_PRESENT;

                dev_printk(KERN_NOTICE, &skt->dev,
                           "pccard: %s card inserted into slot %d\n",
                           (skt->state & SOCKET_CARDBUS) ? "CardBus" : "PCMCIA",
                           skt->sock);

#ifdef CONFIG_CARDBUS
                if (skt->state & SOCKET_CARDBUS) {
                        cb_alloc(skt);
                        skt->state |= SOCKET_CARDBUS_CONFIG;
                }
#endif
                dev_dbg(&skt->dev, "insert done\n");
                mutex_unlock(&skt->ops_mutex);

                if (!(skt->state & SOCKET_CARDBUS) && (skt->callback))
                        skt->callback->add(skt);
        } else {
                mutex_unlock(&skt->ops_mutex);
                socket_shutdown(skt);
        }

        return ret;
}

static int socket_suspend(struct pcmcia_socket *skt)
{
        if (skt->state & SOCKET_SUSPEND)
                return -EBUSY;

        mutex_lock(&skt->ops_mutex);
        skt->suspended_state = skt->state;

        skt->socket = dead_socket;
        skt->ops->set_socket(skt, &skt->socket);
        if (skt->ops->suspend)
                skt->ops->suspend(skt);
        skt->state |= SOCKET_SUSPEND;
        mutex_unlock(&skt->ops_mutex);
        return 0;
}

static int socket_early_resume(struct pcmcia_socket *skt)
{
        mutex_lock(&skt->ops_mutex);
        skt->socket = dead_socket;
        skt->ops->init(skt);
        skt->ops->set_socket(skt, &skt->socket);
        if (skt->state & SOCKET_PRESENT)
                skt->resume_status = socket_setup(skt, resume_delay);
        mutex_unlock(&skt->ops_mutex);
        return 0;
}

static int socket_late_resume(struct pcmcia_socket *skt)
{
        int ret;

        mutex_lock(&skt->ops_mutex);
        skt->state &= ~SOCKET_SUSPEND;
        mutex_unlock(&skt->ops_mutex);

        if (!(skt->state & SOCKET_PRESENT)) {
                ret = socket_insert(skt);
                if (ret == -ENODEV)
                        ret = 0;
                return ret;
        }

        if (skt->resume_status) {
                socket_shutdown(skt);
                return 0;
        }

        if (skt->suspended_state != skt->state) {
                dev_dbg(&skt->dev,
                        "suspend state 0x%x != resume state 0x%x\n",
                        skt->suspended_state, skt->state);

                socket_shutdown(skt);
                return socket_insert(skt);
        }

#ifdef CONFIG_CARDBUS
        if (skt->state & SOCKET_CARDBUS) {
                /* We can't be sure the CardBus card is the same
                 * as the one previously inserted. Therefore, remove
                 * and re-add... */
                cb_free(skt);
                cb_alloc(skt);
                return 0;
        }
#endif
        if (!(skt->state & SOCKET_CARDBUS) && (skt->callback))
                skt->callback->early_resume(skt);
        return 0;
}

/*
 * Resume a socket.  If a card is present, verify its CIS against
 * our cached copy.  If they are different, the card has been
 * replaced, and we need to tell the drivers.
 */
static int socket_resume(struct pcmcia_socket *skt)
{
        if (!(skt->state & SOCKET_SUSPEND))
                return -EBUSY;

        socket_early_resume(skt);
        return socket_late_resume(skt);
}

static void socket_remove(struct pcmcia_socket *skt)
{
        dev_printk(KERN_NOTICE, &skt->dev,
                   "pccard: card ejected from slot %d\n", skt->sock);
        socket_shutdown(skt);
}

/*
 * Process a socket card detect status change.
 *
 * If we don't have a card already present, delay the detect event for
 * about 20ms (to be on the safe side) before reading the socket status.
 *
 * Some i82365-based systems send multiple SS_DETECT events during card
 * insertion, and the "card present" status bit seems to bounce.  This
 * will probably be true with GPIO-based card detection systems after
 * the product has aged.
 */
static void socket_detect_change(struct pcmcia_socket *skt)
{
        if (!(skt->state & SOCKET_SUSPEND)) {
                int status;

                if (!(skt->state & SOCKET_PRESENT))
                        msleep(20);

                skt->ops->get_status(skt, &status);
                if ((skt->state & SOCKET_PRESENT) &&
                     !(status & SS_DETECT))
                        socket_remove(skt);
                if (!(skt->state & SOCKET_PRESENT) &&
                    (status & SS_DETECT))
                        socket_insert(skt);
        }
}

static int pccardd(void *__skt)
{
        struct pcmcia_socket *skt = __skt;
        int ret;

        skt->thread = current;
        skt->socket = dead_socket;
        skt->ops->init(skt);
        skt->ops->set_socket(skt, &skt->socket);

        /* register with the device core */
        ret = device_register(&skt->dev);
        if (ret) {
                dev_printk(KERN_WARNING, &skt->dev,
                           "PCMCIA: unable to register socket\n");
                skt->thread = NULL;
                complete(&skt->thread_done);
                return 0;
        }
        ret = pccard_sysfs_add_socket(&skt->dev);
        if (ret)
                dev_warn(&skt->dev, "err %d adding socket attributes\n", ret);

        complete(&skt->thread_done);

        /* wait for userspace to catch up */
        msleep(250);

        set_freezable();
        for (;;) {
                unsigned long flags;
                unsigned int events;
                unsigned int sysfs_events;

                set_current_state(TASK_INTERRUPTIBLE);

                spin_lock_irqsave(&skt->thread_lock, flags);
                events = skt->thread_events;
                skt->thread_events = 0;
                sysfs_events = skt->sysfs_events;
                skt->sysfs_events = 0;
                spin_unlock_irqrestore(&skt->thread_lock, flags);

                mutex_lock(&skt->skt_mutex);
                if (events & SS_DETECT)
                        socket_detect_change(skt);

                if (sysfs_events) {
                        if (sysfs_events & PCMCIA_UEVENT_EJECT)
                                socket_remove(skt);
                        if (sysfs_events & PCMCIA_UEVENT_INSERT)
                                socket_insert(skt);
                        if ((sysfs_events & PCMCIA_UEVENT_SUSPEND) &&
                                !(skt->state & SOCKET_CARDBUS)) {
                                if (skt->callback)
                                        ret = skt->callback->suspend(skt);
                                else
                                        ret = 0;
                                if (!ret) {
                                        socket_suspend(skt);
                                        msleep(100);
                                }
                        }
                        if ((sysfs_events & PCMCIA_UEVENT_RESUME) &&
                                !(skt->state & SOCKET_CARDBUS)) {
                                ret = socket_resume(skt);
                                if (!ret && skt->callback)
                                        skt->callback->resume(skt);
                        }
                        if ((sysfs_events & PCMCIA_UEVENT_REQUERY) &&
                                !(skt->state & SOCKET_CARDBUS)) {
                                if (!ret && skt->callback)
                                        skt->callback->requery(skt);
                        }
                }
                mutex_unlock(&skt->skt_mutex);

                if (events || sysfs_events)
                        continue;

                if (kthread_should_stop())
                        break;

                schedule();
                try_to_freeze();
        }
        /* make sure we are running before we exit */
        set_current_state(TASK_RUNNING);

        /* shut down socket, if a device is still present */
        if (skt->state & SOCKET_PRESENT) {
                mutex_lock(&skt->skt_mutex);
                socket_remove(skt);
                mutex_unlock(&skt->skt_mutex);
        }

        /* remove from the device core */
        pccard_sysfs_remove_socket(&skt->dev);
        device_unregister(&skt->dev);

        return 0;
}

/*
 * Yenta (at least) probes interrupts before registering the socket and
 * starting the handler thread.
 */
void pcmcia_parse_events(struct pcmcia_socket *s, u_int events)
{
        unsigned long flags;
        dev_dbg(&s->dev, "parse_events: events %08x\n", events);
        if (s->thread) {
                spin_lock_irqsave(&s->thread_lock, flags);
                s->thread_events |= events;
                spin_unlock_irqrestore(&s->thread_lock, flags);

                wake_up_process(s->thread);
        }
} /* pcmcia_parse_events */
EXPORT_SYMBOL(pcmcia_parse_events);

/**
 * pcmcia_parse_uevents() - tell pccardd to issue manual commands
 * @s:          the PCMCIA socket we wan't to command
 * @events:     events to pass to pccardd
 *
 * userspace-issued insert, eject, suspend and resume commands must be
 * handled by pccardd to avoid any sysfs-related deadlocks. Valid events
 * are PCMCIA_UEVENT_EJECT (for eject), PCMCIA_UEVENT__INSERT (for insert),
 * PCMCIA_UEVENT_RESUME (for resume), PCMCIA_UEVENT_SUSPEND (for suspend)
 * and PCMCIA_UEVENT_REQUERY (for re-querying the PCMCIA card).
 */
void pcmcia_parse_uevents(struct pcmcia_socket *s, u_int events)
{
        unsigned long flags;
        dev_dbg(&s->dev, "parse_uevents: events %08x\n", events);
        if (s->thread) {
                spin_lock_irqsave(&s->thread_lock, flags);
                s->sysfs_events |= events;
                spin_unlock_irqrestore(&s->thread_lock, flags);

                wake_up_process(s->thread);
        }
}
EXPORT_SYMBOL(pcmcia_parse_uevents);


/* register pcmcia_callback */
int pccard_register_pcmcia(struct pcmcia_socket *s, struct pcmcia_callback *c)
{
        int ret = 0;

        /* s->skt_mutex also protects s->callback */
        mutex_lock(&s->skt_mutex);

        if (c) {
                /* registration */
                if (s->callback) {
                        ret = -EBUSY;
                        goto err;
                }

                s->callback = c;

                if ((s->state & (SOCKET_PRESENT|SOCKET_CARDBUS)) == SOCKET_PRESENT)
                        s->callback->add(s);
        } else
                s->callback = NULL;
 err:
        mutex_unlock(&s->skt_mutex);

        return ret;
}
EXPORT_SYMBOL(pccard_register_pcmcia);


/* I'm not sure which "reset" function this is supposed to use,
 * but for now, it uses the low-level interface's reset, not the
 * CIS register.
 */

int pcmcia_reset_card(struct pcmcia_socket *skt)
{
        int ret;

        dev_dbg(&skt->dev, "resetting socket\n");

        mutex_lock(&skt->skt_mutex);
        do {
                if (!(skt->state & SOCKET_PRESENT)) {
                        dev_dbg(&skt->dev, "can't reset, not present\n");
                        ret = -ENODEV;
                        break;
                }
                if (skt->state & SOCKET_SUSPEND) {
                        dev_dbg(&skt->dev, "can't reset, suspended\n");
                        ret = -EBUSY;
                        break;
                }
                if (skt->state & SOCKET_CARDBUS) {
                        dev_dbg(&skt->dev, "can't reset, is cardbus\n");
                        ret = -EPERM;
                        break;
                }

                if (skt->callback)
                        skt->callback->suspend(skt);
                mutex_lock(&skt->ops_mutex);
                ret = socket_reset(skt);
                mutex_unlock(&skt->ops_mutex);
                if ((ret == 0) && (skt->callback))
                        skt->callback->resume(skt);

                ret = 0;
        } while (0);
        mutex_unlock(&skt->skt_mutex);

        return ret;
} /* reset_card */
EXPORT_SYMBOL(pcmcia_reset_card);


static int pcmcia_socket_uevent(struct device *dev,
                                struct kobj_uevent_env *env)
{
        struct pcmcia_socket *s = container_of(dev, struct pcmcia_socket, dev);

        if (add_uevent_var(env, "SOCKET_NO=%u", s->sock))
                return -ENOMEM;

        return 0;
}


static struct completion pcmcia_unload;

static void pcmcia_release_socket_class(struct class *data)
{
        complete(&pcmcia_unload);
}


#ifdef CONFIG_PM

static int __pcmcia_pm_op(struct device *dev,
                          int (*callback) (struct pcmcia_socket *skt))
{
        struct pcmcia_socket *s = container_of(dev, struct pcmcia_socket, dev);
        int ret;

        mutex_lock(&s->skt_mutex);
        ret = callback(s);
        mutex_unlock(&s->skt_mutex);

        return ret;
}

static int pcmcia_socket_dev_suspend_noirq(struct device *dev)
{
        return __pcmcia_pm_op(dev, socket_suspend);
}

static int pcmcia_socket_dev_resume_noirq(struct device *dev)
{
        return __pcmcia_pm_op(dev, socket_early_resume);
}

static int __used pcmcia_socket_dev_resume(struct device *dev)
{
        return __pcmcia_pm_op(dev, socket_late_resume);
}

static const struct dev_pm_ops pcmcia_socket_pm_ops = {
        /* dev_resume may be called with IRQs enabled */
        SET_SYSTEM_SLEEP_PM_OPS(NULL,
                                pcmcia_socket_dev_resume)

        /* late suspend must be called with IRQs disabled */
        .suspend_noirq = pcmcia_socket_dev_suspend_noirq,
        .freeze_noirq = pcmcia_socket_dev_suspend_noirq,
        .poweroff_noirq = pcmcia_socket_dev_suspend_noirq,

        /* early resume must be called with IRQs disabled */
        .resume_noirq = pcmcia_socket_dev_resume_noirq,
        .thaw_noirq = pcmcia_socket_dev_resume_noirq,
        .restore_noirq = pcmcia_socket_dev_resume_noirq,
};

#define PCMCIA_SOCKET_CLASS_PM_OPS (&pcmcia_socket_pm_ops)

#else /* CONFIG_PM */

#define PCMCIA_SOCKET_CLASS_PM_OPS NULL

#endif /* CONFIG_PM */

struct class pcmcia_socket_class = {
        .name = "pcmcia_socket",
        .dev_uevent = pcmcia_socket_uevent,
        .dev_release = pcmcia_release_socket,
        .class_release = pcmcia_release_socket_class,
        .pm = PCMCIA_SOCKET_CLASS_PM_OPS,
};
EXPORT_SYMBOL(pcmcia_socket_class);


static int __init init_pcmcia_cs(void)
{
        init_completion(&pcmcia_unload);
        return class_register(&pcmcia_socket_class);
}

static void __exit exit_pcmcia_cs(void)
{
        class_unregister(&pcmcia_socket_class);
        wait_for_completion(&pcmcia_unload);
}

subsys_initcall(init_pcmcia_cs);
module_exit(exit_pcmcia_cs);