/*
* Block driver for media (i.e., flash cards)
*
* Copyright 2002 Hewlett-Packard Company
* Copyright 2005-2008 Pierre Ossman
*
* Use consistent with the GNU GPL is permitted,
* provided that this copyright notice is
* preserved in its entirety in all copies and derived works.
*
* HEWLETT-PACKARD COMPANY MAKES NO WARRANTIES, EXPRESSED OR IMPLIED,
* AS TO THE USEFULNESS OR CORRECTNESS OF THIS CODE OR ITS
* FITNESS FOR ANY PARTICULAR PURPOSE.
*
* Many thanks to Alessandro Rubini and Jonathan Corbet!
*
* Author: Andrew Christian
* 28 May 2002
*/
#include <linux/moduleparam.h>
#include <linux/module.h>
#include <linux/init.h>
#include <linux/kernel.h>
#include <linux/fs.h>
#include <linux/slab.h>
#include <linux/errno.h>
#include <linux/hdreg.h>
#include <linux/kdev_t.h>
#include <linux/blkdev.h>
#include <linux/mutex.h>
#include <linux/scatterlist.h>
#include <linux/string_helpers.h>
#include <linux/mmc/card.h>
#include <linux/mmc/host.h>
#include <linux/mmc/mmc.h>
#include <linux/mmc/sd.h>
#include <asm/system.h>
#include <asm/uaccess.h>
#include "queue.h"
MODULE_ALIAS("mmc:block");
#ifdef MODULE_PARAM_PREFIX
#undef MODULE_PARAM_PREFIX
#endif
#define MODULE_PARAM_PREFIX "mmcblk."
static DEFINE_MUTEX(block_mutex);
#define INAND_CMD38_ARG_EXT_CSD 113
#define INAND_CMD38_ARG_ERASE 0x00
#define INAND_CMD38_ARG_TRIM 0x01
#define INAND_CMD38_ARG_SECERASE 0x80
#define INAND_CMD38_ARG_SECTRIM1 0x81
#define INAND_CMD38_ARG_SECTRIM2 0x88
/*
* The defaults come from config options but can be overriden by module
* or bootarg options.
*/
static int perdev_minors = CONFIG_MMC_BLOCK_MINORS;
/*
* We've only got one major, so number of mmcblk devices is
* limited to 256 / number of minors per device.
*/
static int max_devices;
/* 256 minors, so at most 256 separate devices */
static DECLARE_BITMAP(dev_use, 256);
/*
* There is one mmc_blk_data per slot.
*/
struct mmc_blk_data {
spinlock_t lock;
struct gendisk *disk;
struct mmc_queue queue;
unsigned int usage;
unsigned int read_only;
};
static DEFINE_MUTEX(open_lock);
module_param(perdev_minors, int, 0444);
MODULE_PARM_DESC(perdev_minors, "Minors numbers to allocate per device");
static struct mmc_blk_data *mmc_blk_get(struct gendisk *disk)
{
struct mmc_blk_data *md;
mutex_lock(&open_lock);
md = disk->private_data;
if (md && md->usage == 0)
md = NULL;
if (md)
md->usage++;
mutex_unlock(&open_lock);
return md;
}
static void mmc_blk_put(struct mmc_blk_data *md)
{
mutex_lock(&open_lock);
md->usage--;
if (md->usage == 0) {
int devidx = md->disk->first_minor / perdev_minors;
blk_cleanup_queue(md->queue.queue);
__clear_bit(devidx, dev_use);
put_disk(md->disk);
kfree(md);
}
mutex_unlock(&open_lock);
}
static int mmc_blk_open(struct block_device *bdev, fmode_t mode)
{
struct mmc_blk_data *md = mmc_blk_get(bdev->bd_disk);
int ret = -ENXIO;
mutex_lock(&block_mutex);
if (md) {
if (md->usage == 2)
check_disk_change(bdev);
ret = 0;
if ((mode & FMODE_WRITE) && md->read_only) {
mmc_blk_put(md);
ret = -EROFS;
}
}
mutex_unlock(&block_mutex);
return ret;
}
static int mmc_blk_release(struct gendisk *disk, fmode_t mode)
{
struct mmc_blk_data *md = disk->private_data;
mutex_lock(&block_mutex);
mmc_blk_put(md);
mutex_unlock(&block_mutex);
return 0;
}
static int
mmc_blk_getgeo(struct block_device *bdev, struct hd_geometry *geo)
{
geo->cylinders = get_capacity(bdev->bd_disk) / (4 * 16);
geo->heads = 4;
geo->sectors = 16;
return 0;
}
static const struct block_device_operations mmc_bdops = {
.open = mmc_blk_open,
.release = mmc_blk_release,
.getgeo = mmc_blk_getgeo,
.owner = THIS_MODULE,
};
struct mmc_blk_request {
struct mmc_request mrq;
struct mmc_command cmd;
struct mmc_command stop;
struct mmc_data data;
};
static u32 mmc_sd_num_wr_blocks(struct mmc_card *card)
{
int err;
u32 result;
__be32 *blocks;
struct mmc_request mrq;
struct mmc_command cmd;
struct mmc_data data;
unsigned int timeout_us;
struct scatterlist sg;
memset(&cmd, 0, sizeof(struct mmc_command));
cmd.opcode = MMC_APP_CMD;
cmd.arg = card->rca << 16;
cmd.flags = MMC_RSP_SPI_R1 | MMC_RSP_R1 | MMC_CMD_AC;
err = mmc_wait_for_cmd(card->host, &cmd, 0);
if (err)
return (u32)-1;
if (!mmc_host_is_spi(card->host) && !(cmd.resp[0] & R1_APP_CMD))
return (u32)-1;
memset(&cmd, 0, sizeof(struct mmc_command));
cmd.opcode = SD_APP_SEND_NUM_WR_BLKS;
cmd.arg = 0;
cmd.flags = MMC_RSP_SPI_R1 | MMC_RSP_R1 | MMC_CMD_ADTC;
memset(&data, 0, sizeof(struct mmc_data));
data.timeout_ns = card->csd.tacc_ns * 100;
data.timeout_clks = card->csd.tacc_clks * 100;
timeout_us = data.timeout_ns / 1000;
timeout_us += data.timeout_clks * 1000 /
(card->host->ios.clock / 1000);
if (timeout_us > 100000) {
data.timeout_ns = 100000000;
data.timeout_clks = 0;
}
data.blksz = 4;
data.blocks = 1;
data.flags = MMC_DATA_READ;
data.sg = &sg;
data.sg_len = 1;
memset(&mrq, 0, sizeof(struct mmc_request));
mrq.cmd = &cmd;
mrq.data = &data;
blocks = kmalloc(4, GFP_KERNEL);
if (!blocks)
return (u32)-1;
sg_init_one(&sg, blocks, 4);
mmc_wait_for_req(card->host, &mrq);
result = ntohl(*blocks);
kfree(blocks);
if (cmd.error || data.error)
result = (u32)-1;
return result;
}
static u32 get_card_status(struct mmc_card *card, struct request *req)
{
struct mmc_command cmd;
int err;
memset(&cmd, 0, sizeof(struct mmc_command));
cmd.opcode = MMC_SEND_STATUS;
if (!mmc_host_is_spi(card->host))
cmd.arg = card->rca << 16;
cmd.flags = MMC_RSP_SPI_R2 | MMC_RSP_R1 | MMC_CMD_AC;
err = mmc_wait_for_cmd(card->host, &cmd, 0);
if (err)
printk(KERN_ERR "%s: error %d sending status command",
req->rq_disk->disk_name, err);
return cmd.resp[0];
}
static int mmc_blk_issue_discard_rq(struct mmc_queue *mq, struct request *req)
{
struct mmc_blk_data *md = mq->data;
struct mmc_card *card = md->queue.card;
unsigned int from, nr, arg;
int err = 0;
mmc_claim_host(card->host);
if (!mmc_can_erase(card)) {
err = -EOPNOTSUPP;
goto out;
}
from = blk_rq_pos(req);
nr = blk_rq_sectors(req);
if (mmc_can_trim(card))
arg = MMC_TRIM_ARG;
else
arg = MMC_ERASE_ARG;
if (card->quirks & MMC_QUIRK_INAND_CMD38) {
err = mmc_switch(card, EXT_CSD_CMD_SET_NORMAL,
INAND_CMD38_ARG_EXT_CSD,
arg == MMC_TRIM_ARG ?
INAND_CMD38_ARG_TRIM :
INAND_CMD38_ARG_ERASE);
if (err)
goto out;
}
err = mmc_erase(card, from, nr, arg);
out:
spin_lock_irq(&md->lock);
__blk_end_request(req, err, blk_rq_bytes(req));
spin_unlock_irq(&md->lock);
mmc_release_host(card->host);
return err ? 0 : 1;
}
static int mmc_blk_issue_secdiscard_rq(struct mmc_queue *mq,
struct request *req)
{
struct mmc_blk_data *md = mq->data;
struct mmc_card *card = md->queue.card;
unsigned int from, nr, arg;
int err = 0;
mmc_claim_host(card->host);
if (!mmc_can_secure_erase_trim(card)) {
err = -EOPNOTSUPP;
goto out;
}
from = blk_rq_pos(req);
nr = blk_rq_sectors(req);
if (mmc_can_trim(card) && !mmc_erase_group_aligned(card, from, nr))
arg = MMC_SECURE_TRIM1_ARG;
else
arg = MMC_SECURE_ERASE_ARG;
if (card->quirks & MMC_QUIRK_INAND_CMD38) {
err = mmc_switch(card, EXT_CSD_CMD_SET_NORMAL,
INAND_CMD38_ARG_EXT_CSD,
arg == MMC_SECURE_TRIM1_ARG ?
INAND_CMD38_ARG_SECTRIM1 :
INAND_CMD38_ARG_SECERASE);
if (err)
goto out;
}
err = mmc_erase(card, from, nr, arg);
if (!err && arg == MMC_SECURE_TRIM1_ARG) {
if (card->quirks & MMC_QUIRK_INAND_CMD38) {
err = mmc_switch(card, EXT_CSD_CMD_SET_NORMAL,
INAND_CMD38_ARG_EXT_CSD,
INAND_CMD38_ARG_SECTRIM2);
if (err)
goto out;
}
err = mmc_erase(card, from, nr, MMC_SECURE_TRIM2_ARG);
}
out:
spin_lock_irq(&md->lock);
__blk_end_request(req, err, blk_rq_bytes(req));
spin_unlock_irq(&md->lock);
mmc_release_host(card->host);
return err ? 0 : 1;
}
static int mmc_blk_issue_rw_rq(struct mmc_queue *mq, struct request *req)
{
struct mmc_blk_data *md = mq->data;
struct mmc_card *card = md->queue.card;
struct mmc_blk_request brq;
int ret = 1, disable_multi = 0;
mmc_claim_host(card->host);
do {
struct mmc_command cmd;
u32 readcmd, writecmd, status = 0;
memset(&brq, 0, sizeof(struct mmc_blk_request));
brq.mrq.cmd = &brq.cmd;
brq.mrq.data = &brq.data;
brq.cmd.arg = blk_rq_pos(req);
if (!mmc_card_blockaddr(card))
brq.cmd.arg <<= 9;
brq.cmd.flags = MMC_RSP_SPI_R1 | MMC_RSP_R1 | MMC_CMD_ADTC;
brq.data.blksz = 512;
brq.stop.opcode = MMC_STOP_TRANSMISSION;
brq.stop.arg = 0;
brq.stop.flags = MMC_RSP_SPI_R1B | MMC_RSP_R1B | MMC_CMD_AC;
brq.data.blocks = blk_rq_sectors(req);
/*
* The block layer doesn't support all sector count
* restrictions, so we need to be prepared for too big
* requests.
*/
if (brq.data.blocks > card->host->max_blk_count)
brq.data.blocks = card->host->max_blk_count;
/*
* After a read error, we redo the request one sector at a time
* in order to accurately determine which sectors can be read
* successfully.
*/
if (disable_multi && brq.data.blocks > 1)
brq.data.blocks = 1;
if (brq.data.blocks > 1) {
/* SPI multiblock writes terminate using a special
* token, not a STOP_TRANSMISSION request.
*/
if (!mmc_host_is_spi(card->host)
|| rq_data_dir(req) == READ)
brq.mrq.stop = &brq.stop;
readcmd = MMC_READ_MULTIPLE_BLOCK;
writecmd = MMC_WRITE_MULTIPLE_BLOCK;
} else {
brq.mrq.stop = NULL;
readcmd = MMC_READ_SINGLE_BLOCK;
writecmd = MMC_WRITE_BLOCK;
}
if (rq_data_dir(req) == READ) {
brq.cmd.opcode = readcmd;
brq.data.flags |= MMC_DATA_READ;
} else {
brq.cmd.opcode = writecmd;
brq.data.flags |= MMC_DATA_WRITE;
}
mmc_set_data_timeout(&brq.data, card);
brq.data.sg = mq->sg;
brq.data.sg_len = mmc_queue_map_sg(mq);
/*
* Adjust the sg list so it is the same size as the
* request.
*/
if (brq.data.blocks != blk_rq_sectors(req)) {
int i, data_size = brq.data.blocks << 9;
struct scatterlist *sg;
for_each_sg(brq.data.sg, sg, brq.data.sg_len, i) {
data_size -= sg->length;
if (data_size <= 0) {
sg->length += data_size;
i++;
break;
}
}
brq.data.sg_len = i;
}
mmc_queue_bounce_pre(mq);
mmc_wait_for_req(card->host, &brq.mrq);
mmc_queue_bounce_post(mq);
/*
* Check for errors here, but don't jump to cmd_err
* until later as we need to wait for the card to leave
* programming mode even when things go wrong.
*/
if (brq.cmd.error || brq.data.error || brq.stop.error) {
if (brq.data.blocks > 1 && rq_data_dir(req) == READ) {
/* Redo read one sector at a time */
printk(KERN_WARNING "%s: retrying using single "
"block read\n", req->rq_disk->disk_name);
disable_multi = 1;
continue;
}
status = get_card_status(card, req);
} else if (disable_multi == 1) {
disable_multi = 0;
}
if (brq.cmd.error) {
printk(KERN_ERR "%s: error %d sending read/write "
"command, response %#x, card status %#x\n",
req->rq_disk->disk_name, brq.cmd.error,
brq.cmd.resp[0], status);
}
if (brq.data.error) {
if (brq.data.error == -ETIMEDOUT && brq.mrq.stop)
/* 'Stop' response contains card status */
status = brq.mrq.stop->resp[0];
printk(KERN_ERR "%s: error %d transferring data,"
" sector %u, nr %u, card status %#x\n",
req->rq_disk->disk_name, brq.data.error,
(unsigned)blk_rq_pos(req),
(unsigned)blk_rq_sectors(req), status);
}
if (brq.stop.error) {
printk(KERN_ERR "%s: error %d sending stop command, "
"response %#x, card status %#x\n",
req->rq_disk->disk_name, brq.stop.error,
brq.stop.resp[0], status);
}
if (!mmc_host_is_spi(card->host) && rq_data_dir(req) != READ) {
do {
int err;
cmd.opcode = MMC_SEND_STATUS;
cmd.arg = card->rca << 16;
cmd.flags = MMC_RSP_R1 | MMC_CMD_AC;
err = mmc_wait_for_cmd(card->host, &cmd, 5);
if (err) {
printk(KERN_ERR "%s: error %d requesting status\n",
req->rq_disk->disk_name, err);
goto cmd_err;
}
/*
* Some cards mishandle the status bits,
* so make sure to check both the busy
* indication and the card state.
*/
} while (!(cmd.resp[0] & R1_READY_FOR_DATA) ||
(R1_CURRENT_STATE(cmd.resp[0]) == 7));
#if 0
if (cmd.resp[0] & ~0x00000900)
printk(KERN_ERR "%s: status = %08x\n",
req->rq_disk->disk_name, cmd.resp[0]);
if (mmc_decode_status(cmd.resp))
goto cmd_err;
#endif
}
if (brq.cmd.error || brq.stop.error || brq.data.error) {
if (rq_data_dir(req) == READ) {
/*
* After an error, we redo I/O one sector at a
* time, so we only reach here after trying to
* read a single sector.
*/
spin_lock_irq(&md->lock);
ret = __blk_end_request(req, -EIO, brq.data.blksz);
spin_unlock_irq(&md->lock);
continue;
}
goto cmd_err;
}
/*
* A block was successfully transferred.
*/
spin_lock_irq(&md->lock);
ret = __blk_end_request(req, 0, brq.data.bytes_xfered);
spin_unlock_irq(&md->lock);
} while (ret);
mmc_release_host(card->host);
return 1;
cmd_err:
/*
* If this is an SD card and we're writing, we can first
* mark the known good sectors as ok.
*
* If the card is not SD, we can still ok written sectors
* as reported by the controller (which might be less than
* the real number of written sectors, but never more).
*/
if (mmc_card_sd(card)) {
u32 blocks;
blocks = mmc_sd_num_wr_blocks(card);
if (blocks != (u32)-1) {
spin_lock_irq(&md->lock);
ret = __blk_end_request(req, 0, blocks << 9);
spin_unlock_irq(&md->lock);
}
} else {
spin_lock_irq(&md->lock);
ret = __blk_end_request(req, 0, brq.data.bytes_xfered);
spin_unlock_irq(&md->lock);
}
mmc_release_host(card->host);
spin_lock_irq(&md->lock);
while (ret)
ret = __blk_end_request(req, -EIO, blk_rq_cur_bytes(req));
spin_unlock_irq(&md->lock);
return 0;
}
static int
mmc_blk_set_blksize(struct mmc_blk_data *md, struct mmc_card *card);
static int mmc_blk_issue_rq(struct mmc_queue *mq, struct request *req)
{
#ifdef CONFIG_MMC_BLOCK_DEFERRED_RESUME
struct mmc_blk_data *md = mq->data;
struct mmc_card *card = md->queue.card;
if (mmc_bus_needs_resume(card->host)) {
mmc_resume_bus(card->host);
mmc_blk_set_blksize(md, card);
}
#endif
if (req->cmd_flags & REQ_DISCARD) {
if (req->cmd_flags & REQ_SECURE)
return mmc_blk_issue_secdiscard_rq(mq, req);
else
return mmc_blk_issue_discard_rq(mq, req);
} else {
return mmc_blk_issue_rw_rq(mq, req);
}
}
static inline int mmc_blk_readonly(struct mmc_card *card)
{
return mmc_card_readonly(card) ||
!(card->csd.cmdclass & CCC_BLOCK_WRITE);
}
static struct mmc_blk_data *mmc_blk_alloc(struct mmc_card *card)
{
struct mmc_blk_data *md;
int devidx, ret;
devidx = find_first_zero_bit(dev_use, max_devices);
if (devidx >= max_devices)
return ERR_PTR(-ENOSPC);
__set_bit(devidx, dev_use);
md = kzalloc(sizeof(struct mmc_blk_data), GFP_KERNEL);
if (!md) {
ret = -ENOMEM;
goto out;
}
/*
* Set the read-only status based on the supported commands
* and the write protect switch.
*/
md->read_only = mmc_blk_readonly(card);
md->disk = alloc_disk(perdev_minors);
if (md->disk == NULL) {
ret = -ENOMEM;
goto err_kfree;
}
spin_lock_init(&md->lock);
md->usage = 1;
ret = mmc_init_queue(&md->queue, card, &md->lock);
if (ret)
goto err_putdisk;
md->queue.issue_fn = mmc_blk_issue_rq;
md->queue.data = md;
md->disk->major = MMC_BLOCK_MAJOR;
md->disk->first_minor = devidx * perdev_minors;
md->disk->fops = &mmc_bdops;
md->disk->private_data = md;
md->disk->queue = md->queue.queue;
md->disk->driverfs_dev = &card->dev;
md->disk->flags = GENHD_FL_EXT_DEVT;
set_disk_ro(md->disk, md->read_only);
/*
* As discussed on lkml, GENHD_FL_REMOVABLE should:
*
* - be set for removable media with permanent block devices
* - be unset for removable block devices with permanent media
*
* Since MMC block devices clearly fall under the second
* case, we do not set GENHD_FL_REMOVABLE. Userspace
* should use the block device creation/destruction hotplug
* messages to tell when the card is present.
*/
snprintf(md->disk->disk_name, sizeof(md->disk->disk_name),
"mmcblk%d", devidx);
blk_queue_logical_block_size(md->queue.queue, 512);
if (!mmc_card_sd(card) && mmc_card_blockaddr(card)) {
/*
* The EXT_CSD sector count is in number or 512 byte
* sectors.
*/
set_capacity(md->disk, card->ext_csd.sectors);
} else {
/*
* The CSD capacity field is in units of read_blkbits.
* set_capacity takes units of 512 bytes.
*/
set_capacity(md->disk,
card->csd.capacity << (card->csd.read_blkbits - 9));
}
return md;
err_putdisk:
put_disk(md->disk);
err_kfree:
kfree(md);
out:
return ERR_PTR(ret);
}
static int
mmc_blk_set_blksize(struct mmc_blk_data *md, struct mmc_card *card)
{
int err;
mmc_claim_host(card->host);
err = mmc_set_blocklen(card, 512);
mmc_release_host(card->host);
if (err) {
printk(KERN_ERR "%s: unable to set block size to 512: %d\n",
md->disk->disk_name, err);
return -EINVAL;
}
return 0;
}
static const struct mmc_fixup blk_fixups[] =
{
MMC_FIXUP("SEM16G", 0x2, 0x100, add_quirk, MMC_QUIRK_INAND_CMD38),
MMC_FIXUP("SEM32G", 0x2, 0x100, add_quirk, MMC_QUIRK_INAND_CMD38),
END_FIXUP
};
static int mmc_blk_probe(struct mmc_card *card)
{
struct mmc_blk_data *md;
int err;
char cap_str[10];
/*
* Check that the card supports the command class(es) we need.
*/
if (!(card->csd.cmdclass & CCC_BLOCK_READ))
return -ENODEV;
md = mmc_blk_alloc(card);
if (IS_ERR(md))
return PTR_ERR(md);
err = mmc_blk_set_blksize(md, card);
if (err)
goto out;
string_get_size((u64)get_capacity(md->disk) << 9, STRING_UNITS_2,
cap_str, sizeof(cap_str));
printk(KERN_INFO "%s: %s %s %s %s\n",
md->disk->disk_name, mmc_card_id(card), mmc_card_name(card),
cap_str, md->read_only ? "(ro)" : "");
mmc_set_drvdata(card, md);
mmc_fixup_device(card, blk_fixups);
#ifdef CONFIG_MMC_BLOCK_DEFERRED_RESUME
mmc_set_bus_resume_policy(card->host, 1);
#endif
add_disk(md->disk);
return 0;
out:
mmc_cleanup_queue(&md->queue);
mmc_blk_put(md);
return err;
}
static void mmc_blk_remove(struct mmc_card *card)
{
struct mmc_blk_data *md = mmc_get_drvdata(card);
if (md) {
/* Stop new requests from getting into the queue */
del_gendisk(md->disk);
/* Then flush out any already in there */
mmc_cleanup_queue(&md->queue);
mmc_blk_put(md);
}
mmc_set_drvdata(card, NULL);
#ifdef CONFIG_MMC_BLOCK_DEFERRED_RESUME
mmc_set_bus_resume_policy(card->host, 0);
#endif
}
#ifdef CONFIG_PM
static int mmc_blk_suspend(struct mmc_card *card, pm_message_t state)
{
struct mmc_blk_data *md = mmc_get_drvdata(card);
if (md) {
mmc_queue_suspend(&md->queue);
}
return 0;
}
static int mmc_blk_resume(struct mmc_card *card)
{
struct mmc_blk_data *md = mmc_get_drvdata(card);
if (md) {
#ifndef CONFIG_MMC_BLOCK_DEFERRED_RESUME
mmc_blk_set_blksize(md, card);
#endif
mmc_queue_resume(&md->queue);
}
return 0;
}
#else
#define mmc_blk_suspend NULL
#define mmc_blk_resume NULL
#endif
static struct mmc_driver mmc_driver = {
.drv = {
.name = "mmcblk",
},
.probe = mmc_blk_probe,
.remove = mmc_blk_remove,
.suspend = mmc_blk_suspend,
.resume = mmc_blk_resume,
};
static int __init mmc_blk_init(void)
{
int res;
if (perdev_minors != CONFIG_MMC_BLOCK_MINORS)
pr_info("mmcblk: using %d minors per device\n", perdev_minors);
max_devices = 256 / perdev_minors;
res = register_blkdev(MMC_BLOCK_MAJOR, "mmc");
if (res)
goto out;
res = mmc_register_driver(&mmc_driver);
if (res)
goto out2;
return 0;
out2:
unregister_blkdev(MMC_BLOCK_MAJOR, "mmc");
out:
return res;
}
static void __exit mmc_blk_exit(void)
{
mmc_unregister_driver(&mmc_driver);
unregister_blkdev(MMC_BLOCK_MAJOR, "mmc");
}
module_init(mmc_blk_init);
module_exit(mmc_blk_exit);
MODULE_LICENSE("GPL");
MODULE_DESCRIPTION("Multimedia Card (MMC) block device driver");