// SPDX-License-Identifier: GPL-2.0-or-later
/*
 * Driver for the media bay on the PowerBook 3400 and 2400.
 *
 * Copyright (C) 1998 Paul Mackerras.
 *
 * Various evolutions by Benjamin Herrenschmidt & Henry Worth
 */
#include <linux/types.h>
#include <linux/errno.h>
#include <linux/kernel.h>
#include <linux/delay.h>
#include <linux/sched.h>
#include <linux/timer.h>
#include <linux/stddef.h>
#include <linux/init.h>
#include <linux/kthread.h>
#include <linux/mutex.h>
#include <linux/pgtable.h>
#include <asm/prom.h>
#include <asm/io.h>
#include <asm/machdep.h>
#include <asm/pmac_feature.h>
#include <asm/mediabay.h>
#include <asm/sections.h>
#include <asm/ohare.h>
#include <asm/heathrow.h>
#include <asm/keylargo.h>
#include <linux/adb.h>
#include <linux/pmu.h>

#define MB_FCR32(bay, r)        ((bay)->base + ((r) >> 2))
#define MB_FCR8(bay, r)         (((volatile u8 __iomem *)((bay)->base)) + (r))

#define MB_IN32(bay,r)          (in_le32(MB_FCR32(bay,r)))
#define MB_OUT32(bay,r,v)       (out_le32(MB_FCR32(bay,r), (v)))
#define MB_BIS(bay,r,v)         (MB_OUT32((bay), (r), MB_IN32((bay), r) | (v)))
#define MB_BIC(bay,r,v)         (MB_OUT32((bay), (r), MB_IN32((bay), r) & ~(v)))
#define MB_IN8(bay,r)           (in_8(MB_FCR8(bay,r)))
#define MB_OUT8(bay,r,v)        (out_8(MB_FCR8(bay,r), (v)))

struct media_bay_info;

struct mb_ops {
        char*   name;
        void    (*init)(struct media_bay_info *bay);
        u8      (*content)(struct media_bay_info *bay);
        void    (*power)(struct media_bay_info *bay, int on_off);
        int     (*setup_bus)(struct media_bay_info *bay, u8 device_id);
        void    (*un_reset)(struct media_bay_info *bay);
        void    (*un_reset_ide)(struct media_bay_info *bay);
};

struct media_bay_info {
        u32 __iomem                     *base;
        int                             content_id;
        int                             state;
        int                             last_value;
        int                             value_count;
        int                             timer;
        struct macio_dev                *mdev;
        const struct mb_ops*            ops;
        int                             index;
        int                             cached_gpio;
        int                             sleeping;
        int                             user_lock;
        struct mutex                    lock;
};

#define MAX_BAYS        2

static struct media_bay_info media_bays[MAX_BAYS];
static int media_bay_count = 0;

/*
 * Wait that number of ms between each step in normal polling mode
 */
#define MB_POLL_DELAY   25

/*
 * Consider the media-bay ID value stable if it is the same for
 * this number of milliseconds
 */
#define MB_STABLE_DELAY 100

/* Wait after powering up the media bay this delay in ms
 * timeout bumped for some powerbooks
 */
#define MB_POWER_DELAY  200

/*
 * Hold the media-bay reset signal true for this many ticks
 * after a device is inserted before releasing it.
 */
#define MB_RESET_DELAY  50

/*
 * Wait this long after the reset signal is released and before doing
 * further operations. After this delay, the IDE reset signal is released
 * too for an IDE device
 */
#define MB_SETUP_DELAY  100

/*
 * Wait this many ticks after an IDE device (e.g. CD-ROM) is inserted
 * (or until the device is ready) before calling into the driver
 */
#define MB_IDE_WAIT     1000

/*
 * States of a media bay
 */
enum {
        mb_empty = 0,           /* Idle */
        mb_powering_up,         /* power bit set, waiting MB_POWER_DELAY */
        mb_enabling_bay,        /* enable bits set, waiting MB_RESET_DELAY */
        mb_resetting,           /* reset bit unset, waiting MB_SETUP_DELAY */
        mb_ide_resetting,       /* IDE reset bit unser, waiting MB_IDE_WAIT */
        mb_up,                  /* Media bay full */
        mb_powering_down        /* Powering down (avoid too fast down/up) */
};

#define MB_POWER_SOUND          0x08
#define MB_POWER_FLOPPY         0x04
#define MB_POWER_ATA            0x02
#define MB_POWER_PCI            0x01
#define MB_POWER_OFF            0x00

/*
 * Functions for polling content of media bay
 */
 
static u8
ohare_mb_content(struct media_bay_info *bay)
{
        return (MB_IN32(bay, OHARE_MBCR) >> 12) & 7;
}

static u8
heathrow_mb_content(struct media_bay_info *bay)
{
        return (MB_IN32(bay, HEATHROW_MBCR) >> 12) & 7;
}

static u8
keylargo_mb_content(struct media_bay_info *bay)
{
        int new_gpio;

        new_gpio = MB_IN8(bay, KL_GPIO_MEDIABAY_IRQ) & KEYLARGO_GPIO_INPUT_DATA;
        if (new_gpio) {
                bay->cached_gpio = new_gpio;
                return MB_NO;
        } else if (bay->cached_gpio != new_gpio) {
                MB_BIS(bay, KEYLARGO_MBCR, KL_MBCR_MB0_ENABLE);
                (void)MB_IN32(bay, KEYLARGO_MBCR);
                udelay(5);
                MB_BIC(bay, KEYLARGO_MBCR, 0x0000000F);
                (void)MB_IN32(bay, KEYLARGO_MBCR);
                udelay(5);
                bay->cached_gpio = new_gpio;
        }
        return (MB_IN32(bay, KEYLARGO_MBCR) >> 4) & 7;
}

/*
 * Functions for powering up/down the bay, puts the bay device
 * into reset state as well
 */

static void
ohare_mb_power(struct media_bay_info* bay, int on_off)
{
        if (on_off) {
                /* Power up device, assert it's reset line */
                MB_BIC(bay, OHARE_FCR, OH_BAY_RESET_N);
                MB_BIC(bay, OHARE_FCR, OH_BAY_POWER_N);
        } else {
                /* Disable all devices */
                MB_BIC(bay, OHARE_FCR, OH_BAY_DEV_MASK);
                MB_BIC(bay, OHARE_FCR, OH_FLOPPY_ENABLE);
                /* Cut power from bay, release reset line */
                MB_BIS(bay, OHARE_FCR, OH_BAY_POWER_N);
                MB_BIS(bay, OHARE_FCR, OH_BAY_RESET_N);
                MB_BIS(bay, OHARE_FCR, OH_IDE1_RESET_N);
        }
        MB_BIC(bay, OHARE_MBCR, 0x00000F00);
}

static void
heathrow_mb_power(struct media_bay_info* bay, int on_off)
{
        if (on_off) {
                /* Power up device, assert it's reset line */
                MB_BIC(bay, HEATHROW_FCR, HRW_BAY_RESET_N);
                MB_BIC(bay, HEATHROW_FCR, HRW_BAY_POWER_N);
        } else {
                /* Disable all devices */
                MB_BIC(bay, HEATHROW_FCR, HRW_BAY_DEV_MASK);
                MB_BIC(bay, HEATHROW_FCR, HRW_SWIM_ENABLE);
                /* Cut power from bay, release reset line */
                MB_BIS(bay, HEATHROW_FCR, HRW_BAY_POWER_N);
                MB_BIS(bay, HEATHROW_FCR, HRW_BAY_RESET_N);
                MB_BIS(bay, HEATHROW_FCR, HRW_IDE1_RESET_N);
        }
        MB_BIC(bay, HEATHROW_MBCR, 0x00000F00);
}

static void
keylargo_mb_power(struct media_bay_info* bay, int on_off)
{
        if (on_off) {
                /* Power up device, assert it's reset line */
                MB_BIC(bay, KEYLARGO_MBCR, KL_MBCR_MB0_DEV_RESET);
                MB_BIC(bay, KEYLARGO_MBCR, KL_MBCR_MB0_DEV_POWER);
        } else {
                /* Disable all devices */
                MB_BIC(bay, KEYLARGO_MBCR, KL_MBCR_MB0_DEV_MASK);
                MB_BIC(bay, KEYLARGO_FCR1, KL1_EIDE0_ENABLE);
                /* Cut power from bay, release reset line */
                MB_BIS(bay, KEYLARGO_MBCR, KL_MBCR_MB0_DEV_POWER);
                MB_BIS(bay, KEYLARGO_MBCR, KL_MBCR_MB0_DEV_RESET);
                MB_BIS(bay, KEYLARGO_FCR1, KL1_EIDE0_RESET_N);
        }
        MB_BIC(bay, KEYLARGO_MBCR, 0x0000000F);
}

/*
 * Functions for configuring the media bay for a given type of device,
 * enable the related busses
 */

static int
ohare_mb_setup_bus(struct media_bay_info* bay, u8 device_id)
{
        switch(device_id) {
                case MB_FD:
                case MB_FD1:
                        MB_BIS(bay, OHARE_FCR, OH_BAY_FLOPPY_ENABLE);
                        MB_BIS(bay, OHARE_FCR, OH_FLOPPY_ENABLE);
                        return 0;
                case MB_CD:
                        MB_BIC(bay, OHARE_FCR, OH_IDE1_RESET_N);
                        MB_BIS(bay, OHARE_FCR, OH_BAY_IDE_ENABLE);
                        return 0;
                case MB_PCI:
                        MB_BIS(bay, OHARE_FCR, OH_BAY_PCI_ENABLE);
                        return 0;
        }
        return -ENODEV;
}

static int
heathrow_mb_setup_bus(struct media_bay_info* bay, u8 device_id)
{
        switch(device_id) {
                case MB_FD:
                case MB_FD1:
                        MB_BIS(bay, HEATHROW_FCR, HRW_BAY_FLOPPY_ENABLE);
                        MB_BIS(bay, HEATHROW_FCR, HRW_SWIM_ENABLE);
                        return 0;
                case MB_CD:
                        MB_BIC(bay, HEATHROW_FCR, HRW_IDE1_RESET_N);
                        MB_BIS(bay, HEATHROW_FCR, HRW_BAY_IDE_ENABLE);
                        return 0;
                case MB_PCI:
                        MB_BIS(bay, HEATHROW_FCR, HRW_BAY_PCI_ENABLE);
                        return 0;
        }
        return -ENODEV;
}

static int
keylargo_mb_setup_bus(struct media_bay_info* bay, u8 device_id)
{
        switch(device_id) {
                case MB_CD:
                        MB_BIS(bay, KEYLARGO_MBCR, KL_MBCR_MB0_IDE_ENABLE);
                        MB_BIC(bay, KEYLARGO_FCR1, KL1_EIDE0_RESET_N);
                        MB_BIS(bay, KEYLARGO_FCR1, KL1_EIDE0_ENABLE);
                        return 0;
                case MB_PCI:
                        MB_BIS(bay, KEYLARGO_MBCR, KL_MBCR_MB0_PCI_ENABLE);
                        return 0;
                case MB_SOUND:
                        MB_BIS(bay, KEYLARGO_MBCR, KL_MBCR_MB0_SOUND_ENABLE);
                        return 0;
        }
        return -ENODEV;
}

/*
 * Functions for tweaking resets
 */

static void
ohare_mb_un_reset(struct media_bay_info* bay)
{
        MB_BIS(bay, OHARE_FCR, OH_BAY_RESET_N);
}

static void keylargo_mb_init(struct media_bay_info *bay)
{
        MB_BIS(bay, KEYLARGO_MBCR, KL_MBCR_MB0_ENABLE);
}

static void heathrow_mb_un_reset(struct media_bay_info* bay)
{
        MB_BIS(bay, HEATHROW_FCR, HRW_BAY_RESET_N);
}

static void keylargo_mb_un_reset(struct media_bay_info* bay)
{
        MB_BIS(bay, KEYLARGO_MBCR, KL_MBCR_MB0_DEV_RESET);
}

static void ohare_mb_un_reset_ide(struct media_bay_info* bay)
{
        MB_BIS(bay, OHARE_FCR, OH_IDE1_RESET_N);
}

static void heathrow_mb_un_reset_ide(struct media_bay_info* bay)
{
        MB_BIS(bay, HEATHROW_FCR, HRW_IDE1_RESET_N);
}

static void keylargo_mb_un_reset_ide(struct media_bay_info* bay)
{
        MB_BIS(bay, KEYLARGO_FCR1, KL1_EIDE0_RESET_N);
}

static inline void set_mb_power(struct media_bay_info* bay, int onoff)
{
        /* Power up up and assert the bay reset line */
        if (onoff) {
                bay->ops->power(bay, 1);
                bay->state = mb_powering_up;
                pr_debug("mediabay%d: powering up\n", bay->index);
        } else { 
                /* Make sure everything is powered down & disabled */
                bay->ops->power(bay, 0);
                bay->state = mb_powering_down;
                pr_debug("mediabay%d: powering down\n", bay->index);
        }
        bay->timer = msecs_to_jiffies(MB_POWER_DELAY);
}

static void poll_media_bay(struct media_bay_info* bay)
{
        int id = bay->ops->content(bay);

        static char *mb_content_types[] = {
                "a floppy drive",
                "a floppy drive",
                "an unsupported audio device",
                "an ATA device",
                "an unsupported PCI device",
                "an unknown device",
        };

        if (id != bay->last_value) {
                bay->last_value = id;
                bay->value_count = 0;
                return;
        }
        if (id == bay->content_id)
                return;

        bay->value_count += msecs_to_jiffies(MB_POLL_DELAY);
        if (bay->value_count >= msecs_to_jiffies(MB_STABLE_DELAY)) {
                /* If the device type changes without going thru
                 * "MB_NO", we force a pass by "MB_NO" to make sure
                 * things are properly reset
                 */
                if ((id != MB_NO) && (bay->content_id != MB_NO)) {
                        id = MB_NO;
                        pr_debug("mediabay%d: forcing MB_NO\n", bay->index);
                }
                pr_debug("mediabay%d: switching to %d\n", bay->index, id);
                set_mb_power(bay, id != MB_NO);
                bay->content_id = id;
                if (id >= MB_NO || id < 0)
                        printk(KERN_INFO "mediabay%d: Bay is now empty\n", bay->index);
                else
                        printk(KERN_INFO "mediabay%d: Bay contains %s\n",
                               bay->index, mb_content_types[id]);
        }
}

int check_media_bay(struct macio_dev *baydev)
{
        struct media_bay_info* bay;
        int id;

        if (baydev == NULL)
                return MB_NO;

        /* This returns an instant snapshot, not locking, sine
         * we may be called with the bay lock held. The resulting
         * fuzzyness of the result if called at the wrong time is
         * not actually a huge deal
         */
        bay = macio_get_drvdata(baydev);
        if (bay == NULL)
                return MB_NO;
        id = bay->content_id;
        if (bay->state != mb_up)
                return MB_NO;
        if (id == MB_FD1)
                return MB_FD;
        return id;
}
EXPORT_SYMBOL_GPL(check_media_bay);

void lock_media_bay(struct macio_dev *baydev)
{
        struct media_bay_info* bay;

        if (baydev == NULL)
                return;
        bay = macio_get_drvdata(baydev);
        if (bay == NULL)
                return;
        mutex_lock(&bay->lock);
        bay->user_lock = 1;
}
EXPORT_SYMBOL_GPL(lock_media_bay);

void unlock_media_bay(struct macio_dev *baydev)
{
        struct media_bay_info* bay;

        if (baydev == NULL)
                return;
        bay = macio_get_drvdata(baydev);
        if (bay == NULL)
                return;
        if (bay->user_lock) {
                bay->user_lock = 0;
                mutex_unlock(&bay->lock);
        }
}
EXPORT_SYMBOL_GPL(unlock_media_bay);

static int mb_broadcast_hotplug(struct device *dev, void *data)
{
        struct media_bay_info* bay = data;
        struct macio_dev *mdev;
        struct macio_driver *drv;
        int state;

        if (dev->bus != &macio_bus_type)
                return 0;

        state = bay->state == mb_up ? bay->content_id : MB_NO;
        if (state == MB_FD1)
                state = MB_FD;
        mdev = to_macio_device(dev);
        drv = to_macio_driver(dev->driver);
        if (dev->driver && drv->mediabay_event)
                drv->mediabay_event(mdev, state);
        return 0;
}

static void media_bay_step(int i)
{
        struct media_bay_info* bay = &media_bays[i];

        /* We don't poll when powering down */
        if (bay->state != mb_powering_down)
            poll_media_bay(bay);

        /* If timer expired run state machine */
        if (bay->timer != 0) {
                bay->timer -= msecs_to_jiffies(MB_POLL_DELAY);
                if (bay->timer > 0)
                        return;
                bay->timer = 0;
        }

        switch(bay->state) {
        case mb_powering_up:
                if (bay->ops->setup_bus(bay, bay->last_value) < 0) {
                        pr_debug("mediabay%d: device not supported (kind:%d)\n",
                                 i, bay->content_id);
                        set_mb_power(bay, 0);
                        break;
                }
                bay->timer = msecs_to_jiffies(MB_RESET_DELAY);
                bay->state = mb_enabling_bay;
                pr_debug("mediabay%d: enabling (kind:%d)\n", i, bay->content_id);
                break;
        case mb_enabling_bay:
                bay->ops->un_reset(bay);
                bay->timer = msecs_to_jiffies(MB_SETUP_DELAY);
                bay->state = mb_resetting;
                pr_debug("mediabay%d: releasing bay reset (kind:%d)\n",
                         i, bay->content_id);
                break;
        case mb_resetting:
                if (bay->content_id != MB_CD) {
                        pr_debug("mediabay%d: bay is up (kind:%d)\n", i,
                                 bay->content_id);
                        bay->state = mb_up;
                        device_for_each_child(&bay->mdev->ofdev.dev,
                                              bay, mb_broadcast_hotplug);
                        break;
                }
                pr_debug("mediabay%d: releasing ATA reset (kind:%d)\n",
                         i, bay->content_id);
                bay->ops->un_reset_ide(bay);
                bay->timer = msecs_to_jiffies(MB_IDE_WAIT);
                bay->state = mb_ide_resetting;
                break;

        case mb_ide_resetting:
                pr_debug("mediabay%d: bay is up (kind:%d)\n", i, bay->content_id);
                bay->state = mb_up;
                device_for_each_child(&bay->mdev->ofdev.dev,
                                      bay, mb_broadcast_hotplug);
                break;

        case mb_powering_down:
                bay->state = mb_empty;
                device_for_each_child(&bay->mdev->ofdev.dev,
                                      bay, mb_broadcast_hotplug);
                pr_debug("mediabay%d: end of power down\n", i);
                break;
        }
}

/*
 * This procedure runs as a kernel thread to poll the media bay
 * once each tick and register and unregister the IDE interface
 * with the IDE driver.  It needs to be a thread because
 * ide_register can't be called from interrupt context.
 */
static int media_bay_task(void *x)
{
        int     i;

        while (!kthread_should_stop()) {
                for (i = 0; i < media_bay_count; ++i) {
                        mutex_lock(&media_bays[i].lock);
                        if (!media_bays[i].sleeping)
                                media_bay_step(i);
                        mutex_unlock(&media_bays[i].lock);
                }

                msleep_interruptible(MB_POLL_DELAY);
        }
        return 0;
}

static int media_bay_attach(struct macio_dev *mdev,
                            const struct of_device_id *match)
{
        struct media_bay_info* bay;
        u32 __iomem *regbase;
        struct device_node *ofnode;
        unsigned long base;
        int i;

        ofnode = mdev->ofdev.dev.of_node;

        if (macio_resource_count(mdev) < 1)
                return -ENODEV;
        if (macio_request_resources(mdev, "media-bay"))
                return -EBUSY;
        /* Media bay registers are located at the beginning of the
         * mac-io chip, for now, we trick and align down the first
         * resource passed in
         */
        base = macio_resource_start(mdev, 0) & 0xffff0000u;
        regbase = (u32 __iomem *)ioremap(base, 0x100);
        if (regbase == NULL) {
                macio_release_resources(mdev);
                return -ENOMEM;
        }
        
        i = media_bay_count++;
        bay = &media_bays[i];
        bay->mdev = mdev;
        bay->base = regbase;
        bay->index = i;
        bay->ops = match->data;
        bay->sleeping = 0;
        mutex_init(&bay->lock);

        /* Init HW probing */
        if (bay->ops->init)
                bay->ops->init(bay);

        printk(KERN_INFO "mediabay%d: Registered %s media-bay\n", i, bay->ops->name);

        /* Force an immediate detect */
        set_mb_power(bay, 0);
        msleep(MB_POWER_DELAY);
        bay->content_id = MB_NO;
        bay->last_value = bay->ops->content(bay);
        bay->value_count = msecs_to_jiffies(MB_STABLE_DELAY);
        bay->state = mb_empty;

        /* Mark us ready by filling our mdev data */
        macio_set_drvdata(mdev, bay);

        /* Startup kernel thread */
        if (i == 0)
                kthread_run(media_bay_task, NULL, "media-bay");

        return 0;

}

static int media_bay_suspend(struct macio_dev *mdev, pm_message_t state)
{
        struct media_bay_info   *bay = macio_get_drvdata(mdev);

        if (state.event != mdev->ofdev.dev.power.power_state.event
            && (state.event & PM_EVENT_SLEEP)) {
                mutex_lock(&bay->lock);
                bay->sleeping = 1;
                set_mb_power(bay, 0);
                mutex_unlock(&bay->lock);
                msleep(MB_POLL_DELAY);
                mdev->ofdev.dev.power.power_state = state;
        }
        return 0;
}

static int media_bay_resume(struct macio_dev *mdev)
{
        struct media_bay_info   *bay = macio_get_drvdata(mdev);

        if (mdev->ofdev.dev.power.power_state.event != PM_EVENT_ON) {
                mdev->ofdev.dev.power.power_state = PMSG_ON;

                /* We re-enable the bay using it's previous content
                   only if it did not change. Note those bozo timings,
                   they seem to help the 3400 get it right.
                 */
                /* Force MB power to 0 */
                mutex_lock(&bay->lock);
                set_mb_power(bay, 0);
                msleep(MB_POWER_DELAY);
                if (bay->ops->content(bay) != bay->content_id) {
                        printk("mediabay%d: Content changed during sleep...\n", bay->index);
                        mutex_unlock(&bay->lock);
                        return 0;
                }
                set_mb_power(bay, 1);
                bay->last_value = bay->content_id;
                bay->value_count = msecs_to_jiffies(MB_STABLE_DELAY);
                bay->timer = msecs_to_jiffies(MB_POWER_DELAY);
                do {
                        msleep(MB_POLL_DELAY);
                        media_bay_step(bay->index);
                } while((bay->state != mb_empty) &&
                        (bay->state != mb_up));
                bay->sleeping = 0;
                mutex_unlock(&bay->lock);
        }
        return 0;
}


/* Definitions of "ops" structures.
 */
static const struct mb_ops ohare_mb_ops = {
        .name           = "Ohare",
        .content        = ohare_mb_content,
        .power          = ohare_mb_power,
        .setup_bus      = ohare_mb_setup_bus,
        .un_reset       = ohare_mb_un_reset,
        .un_reset_ide   = ohare_mb_un_reset_ide,
};

static const struct mb_ops heathrow_mb_ops = {
        .name           = "Heathrow",
        .content        = heathrow_mb_content,
        .power          = heathrow_mb_power,
        .setup_bus      = heathrow_mb_setup_bus,
        .un_reset       = heathrow_mb_un_reset,
        .un_reset_ide   = heathrow_mb_un_reset_ide,
};

static const struct mb_ops keylargo_mb_ops = {
        .name           = "KeyLargo",
        .init           = keylargo_mb_init,
        .content        = keylargo_mb_content,
        .power          = keylargo_mb_power,
        .setup_bus      = keylargo_mb_setup_bus,
        .un_reset       = keylargo_mb_un_reset,
        .un_reset_ide   = keylargo_mb_un_reset_ide,
};

/*
 * It seems that the bit for the media-bay interrupt in the IRQ_LEVEL
 * register is always set when there is something in the media bay.
 * This causes problems for the interrupt code if we attach an interrupt
 * handler to the media-bay interrupt, because it tends to go into
 * an infinite loop calling the media bay interrupt handler.
 * Therefore we do it all by polling the media bay once each tick.
 */

static const struct of_device_id media_bay_match[] =
{
        {
        .name           = "media-bay",
        .compatible     = "keylargo-media-bay",
        .data           = &keylargo_mb_ops,
        },
        {
        .name           = "media-bay",
        .compatible     = "heathrow-media-bay",
        .data           = &heathrow_mb_ops,
        },
        {
        .name           = "media-bay",
        .compatible     = "ohare-media-bay",
        .data           = &ohare_mb_ops,
        },
        {},
};

static struct macio_driver media_bay_driver =
{
        .driver = {
                .name           = "media-bay",
                .of_match_table = media_bay_match,
        },
        .probe          = media_bay_attach,
        .suspend        = media_bay_suspend,
        .resume         = media_bay_resume
};

static int __init media_bay_init(void)
{
        int i;

        for (i=0; i<MAX_BAYS; i++) {
                memset((char *)&media_bays[i], 0, sizeof(struct media_bay_info));
                media_bays[i].content_id        = -1;
        }
        if (!machine_is(powermac))
                return 0;

        macio_register_driver(&media_bay_driver);       

        return 0;
}

device_initcall(media_bay_init);