[deliverable/linux.git] / drivers / cdrom / viocd.c

/* -*- linux-c -*-
 *  drivers/cdrom/viocd.c
 *
 *  iSeries Virtual CD Rom
 *
 *  Authors: Dave Boutcher <boutcher@us.ibm.com>
 *           Ryan Arnold <ryanarn@us.ibm.com>
 *           Colin Devilbiss <devilbis@us.ibm.com>
 *           Stephen Rothwell <sfr@au1.ibm.com>
 *
 * (C) Copyright 2000-2004 IBM Corporation
 *
 * This program is free software;  you can redistribute it and/or
 * modify it under the terms of the GNU General Public License as
 * published by the Free Software Foundation; either version 2 of the
 * License, or (at your option) anyu later version.
 *
 * This program is distributed in the hope that it will be useful, but
 * WITHOUT ANY WARRANTY; without even the implied warranty of
 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
 * General Public License for more details.
 *
 * You should have received a copy of the GNU General Public License
 * along with this program; if not, write to the Free Software Foundation,
 * Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA
 *
 * This routine provides access to CD ROM drives owned and managed by an
 * OS/400 partition running on the same box as this Linux partition.
 *
 * All operations are performed by sending messages back and forth to
 * the OS/400 partition.
 */

#include <linux/major.h>
#include <linux/blkdev.h>
#include <linux/cdrom.h>
#include <linux/errno.h>
#include <linux/init.h>
#include <linux/dma-mapping.h>
#include <linux/module.h>
#include <linux/completion.h>
#include <linux/proc_fs.h>
#include <linux/seq_file.h>
#include <linux/scatterlist.h>

#include <asm/vio.h>
#include <asm/iseries/hv_types.h>
#include <asm/iseries/hv_lp_event.h>
#include <asm/iseries/vio.h>
#include <asm/firmware.h>

#define VIOCD_DEVICE                    "iseries/vcd"

#define VIOCD_VERS "1.06"

#define VIOCD_KERN_WARNING              KERN_WARNING "viocd: "
#define VIOCD_KERN_INFO                 KERN_INFO "viocd: "

/*
 * Should probably make this a module parameter....sigh
 */
#define VIOCD_MAX_CD    HVMAXARCHITECTEDVIRTUALCDROMS

static const struct vio_error_entry viocd_err_table[] = {
        {0x0201, EINVAL, "Invalid Range"},
        {0x0202, EINVAL, "Invalid Token"},
        {0x0203, EIO, "DMA Error"},
        {0x0204, EIO, "Use Error"},
        {0x0205, EIO, "Release Error"},
        {0x0206, EINVAL, "Invalid CD"},
        {0x020C, EROFS, "Read Only Device"},
        {0x020D, ENOMEDIUM, "Changed or Missing Volume (or Varied Off?)"},
        {0x020E, EIO, "Optical System Error (Varied Off?)"},
        {0x02FF, EIO, "Internal Error"},
        {0x3010, EIO, "Changed Volume"},
        {0xC100, EIO, "Optical System Error"},
        {0x0000, 0, NULL},
};

/*
 * This is the structure we use to exchange info between driver and interrupt
 * handler
 */
struct viocd_waitevent {
        struct completion       com;
        int                     rc;
        u16                     sub_result;
        int                     changed;
};

/* this is a lookup table for the true capabilities of a device */
struct capability_entry {
        char    *type;
        int     capability;
};

static struct capability_entry capability_table[] __initdata = {
        { "6330", CDC_LOCK | CDC_DVD_RAM | CDC_RAM },
        { "6331", CDC_LOCK | CDC_DVD_RAM | CDC_RAM },
        { "6333", CDC_LOCK | CDC_DVD_RAM | CDC_RAM },
        { "632A", CDC_LOCK | CDC_DVD_RAM | CDC_RAM },
        { "6321", CDC_LOCK },
        { "632B", 0 },
        { NULL  , CDC_LOCK },
};

/* These are our internal structures for keeping track of devices */
static int viocd_numdev;

struct disk_info {
        struct gendisk                  *viocd_disk;
        struct cdrom_device_info        viocd_info;
        struct device                   *dev;
        const char                      *rsrcname;
        const char                      *type;
        const char                      *model;
};
static struct disk_info viocd_diskinfo[VIOCD_MAX_CD];

#define DEVICE_NR(di)   ((di) - &viocd_diskinfo[0])

static spinlock_t viocd_reqlock;

#define MAX_CD_REQ      1

/* procfs support */
static int proc_viocd_show(struct seq_file *m, void *v)
{
        int i;

        for (i = 0; i < viocd_numdev; i++) {
                seq_printf(m, "viocd device %d is iSeries resource %10.10s"
                                "type %4.4s, model %3.3s\n",
                                i, viocd_diskinfo[i].rsrcname,
                                viocd_diskinfo[i].type,
                                viocd_diskinfo[i].model);
        }
        return 0;
}

static int proc_viocd_open(struct inode *inode, struct file *file)
{
        return single_open(file, proc_viocd_show, NULL);
}

static const struct file_operations proc_viocd_operations = {
        .open           = proc_viocd_open,
        .read           = seq_read,
        .llseek         = seq_lseek,
        .release        = single_release,
};

static int viocd_blk_open(struct inode *inode, struct file *file)
{
        struct disk_info *di = inode->i_bdev->bd_disk->private_data;
        return cdrom_open(&di->viocd_info, inode, file);
}

static int viocd_blk_release(struct inode *inode, struct file *file)
{
        struct disk_info *di = inode->i_bdev->bd_disk->private_data;
        return cdrom_release(&di->viocd_info, file);
}

static int viocd_blk_ioctl(struct inode *inode, struct file *file,
                unsigned cmd, unsigned long arg)
{
        struct disk_info *di = inode->i_bdev->bd_disk->private_data;
        return cdrom_ioctl(file, &di->viocd_info, inode, cmd, arg);
}

static int viocd_blk_media_changed(struct gendisk *disk)
{
        struct disk_info *di = disk->private_data;
        return cdrom_media_changed(&di->viocd_info);
}

struct block_device_operations viocd_fops = {
        .owner =                THIS_MODULE,
        .open =                 viocd_blk_open,
        .release =              viocd_blk_release,
        .ioctl =                viocd_blk_ioctl,
        .media_changed =        viocd_blk_media_changed,
};

static int viocd_open(struct cdrom_device_info *cdi, int purpose)
{
        struct disk_info *diskinfo = cdi->handle;
        int device_no = DEVICE_NR(diskinfo);
        HvLpEvent_Rc hvrc;
        struct viocd_waitevent we;

        init_completion(&we.com);
        hvrc = HvCallEvent_signalLpEventFast(viopath_hostLp,
                        HvLpEvent_Type_VirtualIo,
                        viomajorsubtype_cdio | viocdopen,
                        HvLpEvent_AckInd_DoAck, HvLpEvent_AckType_ImmediateAck,
                        viopath_sourceinst(viopath_hostLp),
                        viopath_targetinst(viopath_hostLp),
                        (u64)&we, VIOVERSION << 16, ((u64)device_no << 48),
                        0, 0, 0);
        if (hvrc != 0) {
                printk(VIOCD_KERN_WARNING
                                "bad rc on HvCallEvent_signalLpEventFast %d\n",
                                (int)hvrc);
                return -EIO;
        }

        wait_for_completion(&we.com);

        if (we.rc) {
                const struct vio_error_entry *err =
                        vio_lookup_rc(viocd_err_table, we.sub_result);
                printk(VIOCD_KERN_WARNING "bad rc %d:0x%04X on open: %s\n",
                                we.rc, we.sub_result, err->msg);
                return -err->errno;
        }

        return 0;
}

static void viocd_release(struct cdrom_device_info *cdi)
{
        int device_no = DEVICE_NR((struct disk_info *)cdi->handle);
        HvLpEvent_Rc hvrc;

        hvrc = HvCallEvent_signalLpEventFast(viopath_hostLp,
                        HvLpEvent_Type_VirtualIo,
                        viomajorsubtype_cdio | viocdclose,
                        HvLpEvent_AckInd_NoAck, HvLpEvent_AckType_ImmediateAck,
                        viopath_sourceinst(viopath_hostLp),
                        viopath_targetinst(viopath_hostLp), 0,
                        VIOVERSION << 16, ((u64)device_no << 48), 0, 0, 0);
        if (hvrc != 0)
                printk(VIOCD_KERN_WARNING
                                "bad rc on HvCallEvent_signalLpEventFast %d\n",
                                (int)hvrc);
}

/* Send a read or write request to OS/400 */
static int send_request(struct request *req)
{
        HvLpEvent_Rc hvrc;
        struct disk_info *diskinfo = req->rq_disk->private_data;
        u64 len;
        dma_addr_t dmaaddr;
        int direction;
        u16 cmd;
        struct scatterlist sg;

        BUG_ON(req->nr_phys_segments > 1);

        if (rq_data_dir(req) == READ) {
                direction = DMA_FROM_DEVICE;
                cmd = viomajorsubtype_cdio | viocdread;
        } else {
                direction = DMA_TO_DEVICE;
                cmd = viomajorsubtype_cdio | viocdwrite;
        }

        sg_init_table(&sg, 1);
        if (blk_rq_map_sg(req->q, req, &sg) == 0) {
                printk(VIOCD_KERN_WARNING
                                "error setting up scatter/gather list\n");
                return -1;
        }

        if (dma_map_sg(diskinfo->dev, &sg, 1, direction) == 0) {
                printk(VIOCD_KERN_WARNING "error allocating sg tce\n");
                return -1;
        }
        dmaaddr = sg_dma_address(&sg);
        len = sg_dma_len(&sg);

        hvrc = HvCallEvent_signalLpEventFast(viopath_hostLp,
                        HvLpEvent_Type_VirtualIo, cmd,
                        HvLpEvent_AckInd_DoAck,
                        HvLpEvent_AckType_ImmediateAck,
                        viopath_sourceinst(viopath_hostLp),
                        viopath_targetinst(viopath_hostLp),
                        (u64)req, VIOVERSION << 16,
                        ((u64)DEVICE_NR(diskinfo) << 48) | dmaaddr,
                        (u64)req->sector * 512, len, 0);
        if (hvrc != HvLpEvent_Rc_Good) {
                printk(VIOCD_KERN_WARNING "hv error on op %d\n", (int)hvrc);
                return -1;
        }

        return 0;
}

static void viocd_end_request(struct request *req, int uptodate)
{
        int nsectors = req->hard_nr_sectors;

        /*
         * Make sure it's fully ended, and ensure that we process
         * at least one sector.
         */
        if (blk_pc_request(req))
                nsectors = (req->data_len + 511) >> 9;
        if (!nsectors)
                nsectors = 1;

        if (end_that_request_first(req, uptodate, nsectors))
                BUG();
        add_disk_randomness(req->rq_disk);
        blkdev_dequeue_request(req);
        end_that_request_last(req, uptodate);
}

static int rwreq;

static void do_viocd_request(struct request_queue *q)
{
        struct request *req;

        while ((rwreq == 0) && ((req = elv_next_request(q)) != NULL)) {
                if (!blk_fs_request(req))
                        viocd_end_request(req, 0);
                else if (send_request(req) < 0) {
                        printk(VIOCD_KERN_WARNING
                                        "unable to send message to OS/400!");
                        viocd_end_request(req, 0);
                } else
                        rwreq++;
        }
}

static int viocd_media_changed(struct cdrom_device_info *cdi, int disc_nr)
{
        struct viocd_waitevent we;
        HvLpEvent_Rc hvrc;
        int device_no = DEVICE_NR((struct disk_info *)cdi->handle);

        init_completion(&we.com);

        /* Send the open event to OS/400 */
        hvrc = HvCallEvent_signalLpEventFast(viopath_hostLp,
                        HvLpEvent_Type_VirtualIo,
                        viomajorsubtype_cdio | viocdcheck,
                        HvLpEvent_AckInd_DoAck, HvLpEvent_AckType_ImmediateAck,
                        viopath_sourceinst(viopath_hostLp),
                        viopath_targetinst(viopath_hostLp),
                        (u64)&we, VIOVERSION << 16, ((u64)device_no << 48),
                        0, 0, 0);
        if (hvrc != 0) {
                printk(VIOCD_KERN_WARNING "bad rc on HvCallEvent_signalLpEventFast %d\n",
                                (int)hvrc);
                return -EIO;
        }

        wait_for_completion(&we.com);

        /* Check the return code.  If bad, assume no change */
        if (we.rc) {
                const struct vio_error_entry *err =
                        vio_lookup_rc(viocd_err_table, we.sub_result);
                printk(VIOCD_KERN_WARNING
                                "bad rc %d:0x%04X on check_change: %s; Assuming no change\n",
                                we.rc, we.sub_result, err->msg);
                return 0;
        }

        return we.changed;
}

static int viocd_lock_door(struct cdrom_device_info *cdi, int locking)
{
        HvLpEvent_Rc hvrc;
        u64 device_no = DEVICE_NR((struct disk_info *)cdi->handle);
        /* NOTE: flags is 1 or 0 so it won't overwrite the device_no */
        u64 flags = !!locking;
        struct viocd_waitevent we;

        init_completion(&we.com);

        /* Send the lockdoor event to OS/400 */
        hvrc = HvCallEvent_signalLpEventFast(viopath_hostLp,
                        HvLpEvent_Type_VirtualIo,
                        viomajorsubtype_cdio | viocdlockdoor,
                        HvLpEvent_AckInd_DoAck, HvLpEvent_AckType_ImmediateAck,
                        viopath_sourceinst(viopath_hostLp),
                        viopath_targetinst(viopath_hostLp),
                        (u64)&we, VIOVERSION << 16,
                        (device_no << 48) | (flags << 32), 0, 0, 0);
        if (hvrc != 0) {
                printk(VIOCD_KERN_WARNING "bad rc on HvCallEvent_signalLpEventFast %d\n",
                                (int)hvrc);
                return -EIO;
        }

        wait_for_completion(&we.com);

        if (we.rc != 0)
                return -EIO;
        return 0;
}

static int viocd_packet(struct cdrom_device_info *cdi,
                struct packet_command *cgc)
{
        unsigned int buflen = cgc->buflen;
        int ret = -EIO;

        switch (cgc->cmd[0]) {
        case GPCMD_READ_DISC_INFO:
                {
                        disc_information *di = (disc_information *)cgc->buffer;

                        if (buflen >= 2) {
                                di->disc_information_length = cpu_to_be16(1);
                                ret = 0;
                        }
                        if (buflen >= 3)
                                di->erasable =
                                        (cdi->ops->capability & ~cdi->mask
                                         & (CDC_DVD_RAM | CDC_RAM)) != 0;
                }
                break;
        case GPCMD_GET_CONFIGURATION:
                if (cgc->cmd[3] == CDF_RWRT) {
                        struct rwrt_feature_desc *rfd = (struct rwrt_feature_desc *)(cgc->buffer + sizeof(struct feature_header));

                        if ((buflen >=
                             (sizeof(struct feature_header) + sizeof(*rfd))) &&
                            (cdi->ops->capability & ~cdi->mask
                             & (CDC_DVD_RAM | CDC_RAM))) {
                                rfd->feature_code = cpu_to_be16(CDF_RWRT);
                                rfd->curr = 1;
                                ret = 0;
                        }
                }
                break;
        default:
                if (cgc->sense) {
                        /* indicate Unknown code */
                        cgc->sense->sense_key = 0x05;
                        cgc->sense->asc = 0x20;
                        cgc->sense->ascq = 0x00;
                }
                break;
        }

        cgc->stat = ret;
        return ret;
}

static void restart_all_queues(int first_index)
{
        int i;

        for (i = first_index + 1; i < viocd_numdev; i++)
                if (viocd_diskinfo[i].viocd_disk)
                        blk_run_queue(viocd_diskinfo[i].viocd_disk->queue);
        for (i = 0; i <= first_index; i++)
                if (viocd_diskinfo[i].viocd_disk)
                        blk_run_queue(viocd_diskinfo[i].viocd_disk->queue);
}

/* This routine handles incoming CD LP events */
static void vio_handle_cd_event(struct HvLpEvent *event)
{
        struct viocdlpevent *bevent;
        struct viocd_waitevent *pwe;
        struct disk_info *di;
        unsigned long flags;
        struct request *req;


        if (event == NULL)
                /* Notification that a partition went away! */
                return;
        /* First, we should NEVER get an int here...only acks */
        if (hvlpevent_is_int(event)) {
                printk(VIOCD_KERN_WARNING
                                "Yikes! got an int in viocd event handler!\n");
                if (hvlpevent_need_ack(event)) {
                        event->xRc = HvLpEvent_Rc_InvalidSubtype;
                        HvCallEvent_ackLpEvent(event);
                }
        }

        bevent = (struct viocdlpevent *)event;

        switch (event->xSubtype & VIOMINOR_SUBTYPE_MASK) {
        case viocdopen:
                if (event->xRc == 0) {
                        di = &viocd_diskinfo[bevent->disk];
                        blk_queue_hardsect_size(di->viocd_disk->queue,
                                        bevent->block_size);
                        set_capacity(di->viocd_disk,
                                        bevent->media_size *
                                        bevent->block_size / 512);
                }
                /* FALLTHROUGH !! */
        case viocdlockdoor:
                pwe = (struct viocd_waitevent *)event->xCorrelationToken;
return_complete:
                pwe->rc = event->xRc;
                pwe->sub_result = bevent->sub_result;
                complete(&pwe->com);
                break;

        case viocdcheck:
                pwe = (struct viocd_waitevent *)event->xCorrelationToken;
                pwe->changed = bevent->flags;
                goto return_complete;

        case viocdclose:
                break;

        case viocdwrite:
        case viocdread:
                /*
                 * Since this is running in interrupt mode, we need to
                 * make sure we're not stepping on any global I/O operations
                 */
                di = &viocd_diskinfo[bevent->disk];
                spin_lock_irqsave(&viocd_reqlock, flags);
                dma_unmap_single(di->dev, bevent->token, bevent->len,
                                ((event->xSubtype & VIOMINOR_SUBTYPE_MASK) == viocdread)
                                ?  DMA_FROM_DEVICE : DMA_TO_DEVICE);
                req = (struct request *)bevent->event.xCorrelationToken;
                rwreq--;

                if (event->xRc != HvLpEvent_Rc_Good) {
                        const struct vio_error_entry *err =
                                vio_lookup_rc(viocd_err_table,
                                                bevent->sub_result);
                        printk(VIOCD_KERN_WARNING "request %p failed "
                                        "with rc %d:0x%04X: %s\n",
                                        req, event->xRc,
                                        bevent->sub_result, err->msg);
                        viocd_end_request(req, 0);
                } else
                        viocd_end_request(req, 1);

                /* restart handling of incoming requests */
                spin_unlock_irqrestore(&viocd_reqlock, flags);
                restart_all_queues(bevent->disk);
                break;

        default:
                printk(VIOCD_KERN_WARNING
                                "message with invalid subtype %0x04X!\n",
                                event->xSubtype & VIOMINOR_SUBTYPE_MASK);
                if (hvlpevent_need_ack(event)) {
                        event->xRc = HvLpEvent_Rc_InvalidSubtype;
                        HvCallEvent_ackLpEvent(event);
                }
        }
}

static struct cdrom_device_ops viocd_dops = {
        .open = viocd_open,
        .release = viocd_release,
        .media_changed = viocd_media_changed,
        .lock_door = viocd_lock_door,
        .generic_packet = viocd_packet,
        .capability = CDC_CLOSE_TRAY | CDC_OPEN_TRAY | CDC_LOCK | CDC_SELECT_SPEED | CDC_SELECT_DISC | CDC_MULTI_SESSION | CDC_MCN | CDC_MEDIA_CHANGED | CDC_PLAY_AUDIO | CDC_RESET | CDC_DRIVE_STATUS | CDC_GENERIC_PACKET | CDC_CD_R | CDC_CD_RW | CDC_DVD | CDC_DVD_R | CDC_DVD_RAM | CDC_RAM
};

static int __init find_capability(const char *type)
{
        struct capability_entry *entry;

        for(entry = capability_table; entry->type; ++entry)
                if(!strncmp(entry->type, type, 4))
                        break;
        return entry->capability;
}

static int viocd_probe(struct vio_dev *vdev, const struct vio_device_id *id)
{
        struct gendisk *gendisk;
        int deviceno;
        struct disk_info *d;
        struct cdrom_device_info *c;
        struct request_queue *q;
        struct device_node *node = vdev->dev.archdata.of_node;

        deviceno = vdev->unit_address;
        if (deviceno > VIOCD_MAX_CD)
                return -ENODEV;
        if (!node)
                return -ENODEV;

        if (deviceno >= viocd_numdev)
                viocd_numdev = deviceno + 1;

        d = &viocd_diskinfo[deviceno];
        d->rsrcname = of_get_property(node, "linux,vio_rsrcname", NULL);
        d->type = of_get_property(node, "linux,vio_type", NULL);
        d->model = of_get_property(node, "linux,vio_model", NULL);

        c = &d->viocd_info;

        c->ops = &viocd_dops;
        c->speed = 4;
        c->capacity = 1;
        c->handle = d;
        c->mask = ~find_capability(d->type);
        sprintf(c->name, VIOCD_DEVICE "%c", 'a' + deviceno);

        if (register_cdrom(c) != 0) {
                printk(VIOCD_KERN_WARNING "Cannot register viocd CD-ROM %s!\n",
                                c->name);
                goto out;
        }
        printk(VIOCD_KERN_INFO "cd %s is iSeries resource %10.10s "
                        "type %4.4s, model %3.3s\n",
                        c->name, d->rsrcname, d->type, d->model);
        q = blk_init_queue(do_viocd_request, &viocd_reqlock);
        if (q == NULL) {
                printk(VIOCD_KERN_WARNING "Cannot allocate queue for %s!\n",
                                c->name);
                goto out_unregister_cdrom;
        }
        gendisk = alloc_disk(1);
        if (gendisk == NULL) {
                printk(VIOCD_KERN_WARNING "Cannot create gendisk for %s!\n",
                                c->name);
                goto out_cleanup_queue;
        }
        gendisk->major = VIOCD_MAJOR;
        gendisk->first_minor = deviceno;
        strncpy(gendisk->disk_name, c->name,
                        sizeof(gendisk->disk_name));
        blk_queue_max_hw_segments(q, 1);
        blk_queue_max_phys_segments(q, 1);
        blk_queue_max_sectors(q, 4096 / 512);
        gendisk->queue = q;
        gendisk->fops = &viocd_fops;
        gendisk->flags = GENHD_FL_CD|GENHD_FL_REMOVABLE;
        set_capacity(gendisk, 0);
        gendisk->private_data = d;
        d->viocd_disk = gendisk;
        d->dev = &vdev->dev;
        gendisk->driverfs_dev = d->dev;
        add_disk(gendisk);
        return 0;

out_cleanup_queue:
        blk_cleanup_queue(q);
out_unregister_cdrom:
        unregister_cdrom(c);
out:
        return -ENODEV;
}

static int viocd_remove(struct vio_dev *vdev)
{
        struct disk_info *d = &viocd_diskinfo[vdev->unit_address];

        if (unregister_cdrom(&d->viocd_info) != 0)
                printk(VIOCD_KERN_WARNING
                                "Cannot unregister viocd CD-ROM %s!\n",
                                d->viocd_info.name);
        del_gendisk(d->viocd_disk);
        blk_cleanup_queue(d->viocd_disk->queue);
        put_disk(d->viocd_disk);
        return 0;
}

/**
 * viocd_device_table: Used by vio.c to match devices that we
 * support.
 */
static struct vio_device_id viocd_device_table[] __devinitdata = {
        { "block", "IBM,iSeries-viocd" },
        { "", "" }
};
MODULE_DEVICE_TABLE(vio, viocd_device_table);

static struct vio_driver viocd_driver = {
        .id_table = viocd_device_table,
        .probe = viocd_probe,
        .remove = viocd_remove,
        .driver = {
                .name = "viocd",
                .owner = THIS_MODULE,
        }
};

static int __init viocd_init(void)
{
        struct proc_dir_entry *e;
        int ret = 0;

        if (!firmware_has_feature(FW_FEATURE_ISERIES))
                return -ENODEV;

        if (viopath_hostLp == HvLpIndexInvalid) {
                vio_set_hostlp();
                /* If we don't have a host, bail out */
                if (viopath_hostLp == HvLpIndexInvalid)
                        return -ENODEV;
        }

        printk(VIOCD_KERN_INFO "vers " VIOCD_VERS ", hosting partition %d\n",
                        viopath_hostLp);

        if (register_blkdev(VIOCD_MAJOR, VIOCD_DEVICE) != 0) {
                printk(VIOCD_KERN_WARNING "Unable to get major %d for %s\n",
                                VIOCD_MAJOR, VIOCD_DEVICE);
                return -EIO;
        }

        ret = viopath_open(viopath_hostLp, viomajorsubtype_cdio,
                        MAX_CD_REQ + 2);
        if (ret) {
                printk(VIOCD_KERN_WARNING
                                "error opening path to host partition %d\n",
                                viopath_hostLp);
                goto out_unregister;
        }

        /* Initialize our request handler */
        vio_setHandler(viomajorsubtype_cdio, vio_handle_cd_event);

        spin_lock_init(&viocd_reqlock);

        ret = vio_register_driver(&viocd_driver);
        if (ret)
                goto out_free_info;

        e = create_proc_entry("iSeries/viocd", S_IFREG|S_IRUGO, NULL);
        if (e) {
                e->owner = THIS_MODULE;
                e->proc_fops = &proc_viocd_operations;
        }

        return 0;

out_free_info:
        vio_clearHandler(viomajorsubtype_cdio);
        viopath_close(viopath_hostLp, viomajorsubtype_cdio, MAX_CD_REQ + 2);
out_unregister:
        unregister_blkdev(VIOCD_MAJOR, VIOCD_DEVICE);
        return ret;
}

static void __exit viocd_exit(void)
{
        remove_proc_entry("iSeries/viocd", NULL);
        vio_unregister_driver(&viocd_driver);
        viopath_close(viopath_hostLp, viomajorsubtype_cdio, MAX_CD_REQ + 2);
        vio_clearHandler(viomajorsubtype_cdio);
        unregister_blkdev(VIOCD_MAJOR, VIOCD_DEVICE);
}

module_init(viocd_init);
module_exit(viocd_exit);
MODULE_LICENSE("GPL");