[mirror_ubuntu-artful-kernel.git] / drivers / mmc / mmc_block.c

/*
 * Block driver for media (i.e., flash cards)
 *
 * Copyright 2002 Hewlett-Packard Company
 *
 * 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/sched.h>
#include <linux/kernel.h>
#include <linux/fs.h>
#include <linux/errno.h>
#include <linux/hdreg.h>
#include <linux/kdev_t.h>
#include <linux/blkdev.h>
#include <linux/mutex.h>

#include <linux/mmc/card.h>
#include <linux/mmc/host.h>
#include <linux/mmc/protocol.h>
#include <linux/mmc/host.h>

#include <asm/system.h>
#include <asm/uaccess.h>

#include "mmc_queue.h"

/*
 * max 8 partitions per card
 */
#define MMC_SHIFT	3

static int major;

/*
 * 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	block_bits;
	unsigned int	read_only;
};

static DEFINE_MUTEX(open_lock);

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) {
		put_disk(md->disk);
		mmc_cleanup_queue(&md->queue);
		kfree(md);
	}
	mutex_unlock(&open_lock);
}

static int mmc_blk_open(struct inode *inode, struct file *filp)
{
	struct mmc_blk_data *md;
	int ret = -ENXIO;

	md = mmc_blk_get(inode->i_bdev->bd_disk);
	if (md) {
		if (md->usage == 2)
			check_disk_change(inode->i_bdev);
		ret = 0;

		if ((filp->f_mode & FMODE_WRITE) && md->read_only)
			ret = -EROFS;
	}

	return ret;
}

static int mmc_blk_release(struct inode *inode, struct file *filp)
{
	struct mmc_blk_data *md = inode->i_bdev->bd_disk->private_data;

	mmc_blk_put(md);
	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 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 int mmc_blk_prep_rq(struct mmc_queue *mq, struct request *req)
{
	struct mmc_blk_data *md = mq->data;
	int stat = BLKPREP_OK;

	/*
	 * If we have no device, we haven't finished initialising.
	 */
	if (!md || !mq->card) {
		printk(KERN_ERR "%s: killing request - no device/host\n",
		       req->rq_disk->disk_name);
		stat = BLKPREP_KILL;
	}

	return stat;
}

static int mmc_blk_issue_rq(struct mmc_queue *mq, struct request *req)
{
	struct mmc_blk_data *md = mq->data;
	struct mmc_card *card = md->queue.card;
	int ret;

	if (mmc_card_claim_host(card))
		goto cmd_err;

	do {
		struct mmc_blk_request brq;
		struct mmc_command cmd;
		u32 readcmd, writecmd;

		memset(&brq, 0, sizeof(struct mmc_blk_request));
		brq.mrq.cmd = &brq.cmd;
		brq.mrq.data = &brq.data;

		brq.cmd.arg = req->sector << 9;
		brq.cmd.flags = MMC_RSP_R1 | MMC_CMD_ADTC;
		brq.data.blksz = 1 << md->block_bits;
		brq.data.blocks = req->nr_sectors >> (md->block_bits - 9);
		brq.stop.opcode = MMC_STOP_TRANSMISSION;
		brq.stop.arg = 0;
		brq.stop.flags = MMC_RSP_R1B | MMC_CMD_AC;

		mmc_set_data_timeout(&brq.data, card, rq_data_dir(req) != READ);

		/*
		 * If the host doesn't support multiple block writes, force
		 * block writes to single block.
		 */
		if (rq_data_dir(req) != READ &&
		    !(card->host->caps & MMC_CAP_MULTIWRITE))
			brq.data.blocks = 1;

		if (brq.data.blocks > 1) {
			brq.data.flags |= MMC_DATA_MULTI;
			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;
		}

		brq.data.sg = mq->sg;
		brq.data.sg_len = blk_rq_map_sg(req->q, req, brq.data.sg);

		mmc_wait_for_req(card->host, &brq.mrq);
		if (brq.cmd.error) {
			printk(KERN_ERR "%s: error %d sending read/write command\n",
			       req->rq_disk->disk_name, brq.cmd.error);
			goto cmd_err;
		}

		if (brq.data.error) {
			printk(KERN_ERR "%s: error %d transferring data\n",
			       req->rq_disk->disk_name, brq.data.error);
			goto cmd_err;
		}

		if (brq.stop.error) {
			printk(KERN_ERR "%s: error %d sending stop command\n",
			       req->rq_disk->disk_name, brq.stop.error);
			goto cmd_err;
		}

		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;
			}
		} while (!(cmd.resp[0] & R1_READY_FOR_DATA));

#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

		/*
		 * A block was successfully transferred.
		 */
		spin_lock_irq(&md->lock);
		ret = end_that_request_chunk(req, 1, brq.data.bytes_xfered);
		if (!ret) {
			/*
			 * The whole request completed successfully.
			 */
			add_disk_randomness(req->rq_disk);
			blkdev_dequeue_request(req);
			end_that_request_last(req, 1);
		}
		spin_unlock_irq(&md->lock);
	} while (ret);

	mmc_card_release_host(card);

	return 1;

 cmd_err:
	mmc_card_release_host(card);

	/*
	 * This is a little draconian, but until we get proper
	 * error handling sorted out here, its the best we can
	 * do - especially as some hosts have no idea how much
	 * data was transferred before the error occurred.
	 */
	spin_lock_irq(&md->lock);
	do {
		ret = end_that_request_chunk(req, 0,
				req->current_nr_sectors << 9);
	} while (ret);

	add_disk_randomness(req->rq_disk);
	blkdev_dequeue_request(req);
	end_that_request_last(req, 0);
	spin_unlock_irq(&md->lock);

	return 0;
}

#define MMC_NUM_MINORS	(256 >> MMC_SHIFT)

static unsigned long dev_use[MMC_NUM_MINORS/(8*sizeof(unsigned long))];

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, MMC_NUM_MINORS);
	if (devidx >= MMC_NUM_MINORS)
		return ERR_PTR(-ENOSPC);
	__set_bit(devidx, dev_use);

	md = kmalloc(sizeof(struct mmc_blk_data), GFP_KERNEL);
	if (!md) {
		ret = -ENOMEM;
		goto out;
	}

	memset(md, 0, sizeof(struct mmc_blk_data));

	/*
	 * Set the read-only status based on the supported commands
	 * and the write protect switch.
	 */
	md->read_only = mmc_blk_readonly(card);

	/*
	 * Both SD and MMC specifications state (although a bit
	 * unclearly in the MMC case) that a block size of 512
	 * bytes must always be supported by the card.
	 */
	md->block_bits = 9;

	md->disk = alloc_disk(1 << MMC_SHIFT);
	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.prep_fn = mmc_blk_prep_rq;
	md->queue.issue_fn = mmc_blk_issue_rq;
	md->queue.data = md;

	md->disk->major	= major;
	md->disk->first_minor = devidx << MMC_SHIFT;
	md->disk->fops = &mmc_bdops;
	md->disk->private_data = md;
	md->disk->queue = md->queue.queue;
	md->disk->driverfs_dev = &card->dev;

	/*
	 * 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.
	 */

	sprintf(md->disk->disk_name, "mmcblk%d", devidx);

	blk_queue_hardsect_size(md->queue.queue, 1 << md->block_bits);

	/*
	 * 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)
{
	struct mmc_command cmd;
	int err;

	mmc_card_claim_host(card);
	cmd.opcode = MMC_SET_BLOCKLEN;
	cmd.arg = 1 << md->block_bits;
	cmd.flags = MMC_RSP_R1 | MMC_CMD_AC;
	err = mmc_wait_for_cmd(card->host, &cmd, 5);
	mmc_card_release_host(card);

	if (err) {
		printk(KERN_ERR "%s: unable to set block size to %d: %d\n",
			md->disk->disk_name, cmd.arg, err);
		return -EINVAL;
	}

	return 0;
}

static int mmc_blk_probe(struct mmc_card *card)
{
	struct mmc_blk_data *md;
	int err;

	/*
	 * 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;

	printk(KERN_INFO "%s: %s %s %lluKiB %s\n",
		md->disk->disk_name, mmc_card_id(card), mmc_card_name(card),
		(unsigned long long)(get_capacity(md->disk) >> 1),
		md->read_only ? "(ro)" : "");

	mmc_set_drvdata(card, md);
	add_disk(md->disk);
	return 0;

 out:
	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) {
		int devidx;

		del_gendisk(md->disk);

		/*
		 * I think this is needed.
		 */
		md->disk->queue = NULL;

		devidx = md->disk->first_minor >> MMC_SHIFT;
		__clear_bit(devidx, dev_use);

		mmc_blk_put(md);
	}
	mmc_set_drvdata(card, NULL);
}

#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) {
		mmc_blk_set_blksize(md, card);
		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 = -ENOMEM;

	res = register_blkdev(major, "mmc");
	if (res < 0) {
		printk(KERN_WARNING "Unable to get major %d for MMC media: %d\n",
		       major, res);
		goto out;
	}
	if (major == 0)
		major = res;

	return mmc_register_driver(&mmc_driver);

 out:
	return res;
}

static void __exit mmc_blk_exit(void)
{
	mmc_unregister_driver(&mmc_driver);
	unregister_blkdev(major, "mmc");
}

module_init(mmc_blk_init);
module_exit(mmc_blk_exit);

MODULE_LICENSE("GPL");
MODULE_DESCRIPTION("Multimedia Card (MMC) block device driver");

module_param(major, int, 0444);
MODULE_PARM_DESC(major, "specify the major device number for MMC block driver");
Commit	Line	Data
1da177e4 LT	1	/*
	2	* Block driver for media (i.e., flash cards)
	3	*
	4	* Copyright 2002 Hewlett-Packard Company
	5	*
	6	* Use consistent with the GNU GPL is permitted,
	7	* provided that this copyright notice is
	8	* preserved in its entirety in all copies and derived works.
	9	*
	10	* HEWLETT-PACKARD COMPANY MAKES NO WARRANTIES, EXPRESSED OR IMPLIED,
	11	* AS TO THE USEFULNESS OR CORRECTNESS OF THIS CODE OR ITS
	12	* FITNESS FOR ANY PARTICULAR PURPOSE.
	13	*
	14	* Many thanks to Alessandro Rubini and Jonathan Corbet!
	15	*
	16	* Author: Andrew Christian
	17	* 28 May 2002
	18	*/
	19	#include <linux/moduleparam.h>
	20	#include <linux/module.h>
	21	#include <linux/init.h>
	22
	23	#include <linux/sched.h>
	24	#include <linux/kernel.h>
	25	#include <linux/fs.h>
	26	#include <linux/errno.h>
	27	#include <linux/hdreg.h>
	28	#include <linux/kdev_t.h>
	29	#include <linux/blkdev.h>
a621aaed	30	#include <linux/mutex.h>
1da177e4 LT	31
1da177e4 LT	32	#include <linux/mmc/card.h>
385e3227	33	#include <linux/mmc/host.h>
1da177e4	34	#include <linux/mmc/protocol.h>
db53f28b	35	#include <linux/mmc/host.h>
1da177e4 LT	36
	37	#include <asm/system.h>
	38	#include <asm/uaccess.h>
	39
	40	#include "mmc_queue.h"
	41
	42	/*
	43	* max 8 partitions per card
	44	*/
	45	#define MMC_SHIFT 3
	46
	47	static int major;
	48
	49	/*
	50	* There is one mmc_blk_data per slot.
	51	*/
	52	struct mmc_blk_data {
	53	spinlock_t lock;
	54	struct gendisk *disk;
	55	struct mmc_queue queue;
	56
	57	unsigned int usage;
	58	unsigned int block_bits;
a6f6c96b	59	unsigned int read_only;
1da177e4 LT	60	};
1da177e4 LT	61
a621aaed	62	static DEFINE_MUTEX(open_lock);
1da177e4 LT	63
	64	static struct mmc_blk_data mmc_blk_get(struct gendisk disk)
	65	{
	66	struct mmc_blk_data *md;
	67
a621aaed	68	mutex_lock(&open_lock);
1da177e4 LT	69	md = disk->private_data;
	70	if (md && md->usage == 0)
	71	md = NULL;
	72	if (md)
	73	md->usage++;
a621aaed	74	mutex_unlock(&open_lock);
1da177e4 LT	75
	76	return md;
	77	}
	78
	79	static void mmc_blk_put(struct mmc_blk_data *md)
	80	{
a621aaed	81	mutex_lock(&open_lock);
1da177e4 LT	82	md->usage--;
	83	if (md->usage == 0) {
	84	put_disk(md->disk);
	85	mmc_cleanup_queue(&md->queue);
	86	kfree(md);
	87	}
a621aaed	88	mutex_unlock(&open_lock);
1da177e4 LT	89	}
	90
	91	static int mmc_blk_open(struct inode inode, struct file filp)
	92	{
	93	struct mmc_blk_data *md;
	94	int ret = -ENXIO;
	95
	96	md = mmc_blk_get(inode->i_bdev->bd_disk);
	97	if (md) {
	98	if (md->usage == 2)
	99	check_disk_change(inode->i_bdev);
	100	ret = 0;
a00fc090	101
a6f6c96b	102	if ((filp->f_mode & FMODE_WRITE) && md->read_only)
a00fc090	103	ret = -EROFS;
1da177e4 LT	104	}
	105
	106	return ret;
	107	}
	108
	109	static int mmc_blk_release(struct inode inode, struct file filp)
	110	{
	111	struct mmc_blk_data *md = inode->i_bdev->bd_disk->private_data;
	112
	113	mmc_blk_put(md);
	114	return 0;
	115	}
	116
	117	static int
a885c8c4	118	mmc_blk_getgeo(struct block_device bdev, struct hd_geometry geo)
1da177e4	119	{
a885c8c4 CH	120	geo->cylinders = get_capacity(bdev->bd_disk) / (4 * 16);
	121	geo->heads = 4;
	122	geo->sectors = 16;
	123	return 0;
1da177e4 LT	124	}
	125
	126	static struct block_device_operations mmc_bdops = {
	127	.open = mmc_blk_open,
	128	.release = mmc_blk_release,
a885c8c4	129	.getgeo = mmc_blk_getgeo,
1da177e4 LT	130	.owner = THIS_MODULE,
	131	};
	132
	133	struct mmc_blk_request {
	134	struct mmc_request mrq;
	135	struct mmc_command cmd;
	136	struct mmc_command stop;
	137	struct mmc_data data;
	138	};
	139
	140	static int mmc_blk_prep_rq(struct mmc_queue mq, struct request req)
	141	{
	142	struct mmc_blk_data *md = mq->data;
	143	int stat = BLKPREP_OK;
	144
	145	/*
	146	* If we have no device, we haven't finished initialising.
	147	*/
	148	if (!md \|\| !mq->card) {
	149	printk(KERN_ERR "%s: killing request - no device/host\n",
	150	req->rq_disk->disk_name);
	151	stat = BLKPREP_KILL;
	152	}
	153
	154	return stat;
	155	}
	156
	157	static int mmc_blk_issue_rq(struct mmc_queue mq, struct request req)
	158	{
	159	struct mmc_blk_data *md = mq->data;
	160	struct mmc_card *card = md->queue.card;
	161	int ret;
	162
	163	if (mmc_card_claim_host(card))
	164	goto cmd_err;
	165
	166	do {
	167	struct mmc_blk_request brq;
	168	struct mmc_command cmd;
db53f28b	169	u32 readcmd, writecmd;
1da177e4 LT	170
	171	memset(&brq, 0, sizeof(struct mmc_blk_request));
	172	brq.mrq.cmd = &brq.cmd;
	173	brq.mrq.data = &brq.data;
	174
	175	brq.cmd.arg = req->sector << 9;
e9225176	176	brq.cmd.flags = MMC_RSP_R1 \| MMC_CMD_ADTC;
2c171bf1	177	brq.data.blksz = 1 << md->block_bits;
1da177e4 LT	178	brq.data.blocks = req->nr_sectors >> (md->block_bits - 9);
	179	brq.stop.opcode = MMC_STOP_TRANSMISSION;
	180	brq.stop.arg = 0;
e9225176	181	brq.stop.flags = MMC_RSP_R1B \| MMC_CMD_AC;
1da177e4	182
d773d725	183	mmc_set_data_timeout(&brq.data, card, rq_data_dir(req) != READ);
385e3227	184
db53f28b RK	185	/*
	186	* If the host doesn't support multiple block writes, force
	187	* block writes to single block.
	188	*/
	189	if (rq_data_dir(req) != READ &&
	190	!(card->host->caps & MMC_CAP_MULTIWRITE))
1da177e4	191	brq.data.blocks = 1;
788ee7b0 RK	192
	193	if (brq.data.blocks > 1) {
	194	brq.data.flags \|= MMC_DATA_MULTI;
	195	brq.mrq.stop = &brq.stop;
db53f28b RK	196	readcmd = MMC_READ_MULTIPLE_BLOCK;
db53f28b RK	197	writecmd = MMC_WRITE_MULTIPLE_BLOCK;
788ee7b0 RK	198	} else {
788ee7b0 RK	199	brq.mrq.stop = NULL;
db53f28b RK	200	readcmd = MMC_READ_SINGLE_BLOCK;
	201	writecmd = MMC_WRITE_BLOCK;
	202	}
	203
	204	if (rq_data_dir(req) == READ) {
	205	brq.cmd.opcode = readcmd;
	206	brq.data.flags \|= MMC_DATA_READ;
	207	} else {
	208	brq.cmd.opcode = writecmd;
	209	brq.data.flags \|= MMC_DATA_WRITE;
788ee7b0	210	}
1da177e4 LT	211
	212	brq.data.sg = mq->sg;
	213	brq.data.sg_len = blk_rq_map_sg(req->q, req, brq.data.sg);
	214
	215	mmc_wait_for_req(card->host, &brq.mrq);
	216	if (brq.cmd.error) {
	217	printk(KERN_ERR "%s: error %d sending read/write command\n",
	218	req->rq_disk->disk_name, brq.cmd.error);
	219	goto cmd_err;
	220	}
	221
	222	if (brq.data.error) {
	223	printk(KERN_ERR "%s: error %d transferring data\n",
	224	req->rq_disk->disk_name, brq.data.error);
	225	goto cmd_err;
	226	}
	227
	228	if (brq.stop.error) {
	229	printk(KERN_ERR "%s: error %d sending stop command\n",
	230	req->rq_disk->disk_name, brq.stop.error);
	231	goto cmd_err;
	232	}
	233
	234	do {
	235	int err;
	236
	237	cmd.opcode = MMC_SEND_STATUS;
	238	cmd.arg = card->rca << 16;
e9225176	239	cmd.flags = MMC_RSP_R1 \| MMC_CMD_AC;
1da177e4 LT	240	err = mmc_wait_for_cmd(card->host, &cmd, 5);
	241	if (err) {
	242	printk(KERN_ERR "%s: error %d requesting status\n",
	243	req->rq_disk->disk_name, err);
	244	goto cmd_err;
	245	}
	246	} while (!(cmd.resp[0] & R1_READY_FOR_DATA));
	247
	248	#if 0
	249	if (cmd.resp[0] & ~0x00000900)
	250	printk(KERN_ERR "%s: status = %08x\n",
	251	req->rq_disk->disk_name, cmd.resp[0]);
	252	if (mmc_decode_status(cmd.resp))
	253	goto cmd_err;
	254	#endif
	255
	256	/*
	257	* A block was successfully transferred.
	258	*/
	259	spin_lock_irq(&md->lock);
	260	ret = end_that_request_chunk(req, 1, brq.data.bytes_xfered);
	261	if (!ret) {
	262	/*
	263	* The whole request completed successfully.
	264	*/
	265	add_disk_randomness(req->rq_disk);
	266	blkdev_dequeue_request(req);
8ffdc655	267	end_that_request_last(req, 1);
1da177e4 LT	268	}
	269	spin_unlock_irq(&md->lock);
	270	} while (ret);
	271
	272	mmc_card_release_host(card);
	273
	274	return 1;
	275
	276	cmd_err:
	277	mmc_card_release_host(card);
	278
	279	/*
	280	* This is a little draconian, but until we get proper
	281	* error handling sorted out here, its the best we can
	282	* do - especially as some hosts have no idea how much
	283	* data was transferred before the error occurred.
	284	*/
	285	spin_lock_irq(&md->lock);
	286	do {
	287	ret = end_that_request_chunk(req, 0,
	288	req->current_nr_sectors << 9);
	289	} while (ret);
	290
	291	add_disk_randomness(req->rq_disk);
	292	blkdev_dequeue_request(req);
8ffdc655	293	end_that_request_last(req, 0);
1da177e4 LT	294	spin_unlock_irq(&md->lock);
	295
	296	return 0;
	297	}
	298
	299	#define MMC_NUM_MINORS (256 >> MMC_SHIFT)
	300
	301	static unsigned long dev_use[MMC_NUM_MINORS/(8*sizeof(unsigned long))];
	302
a6f6c96b RK	303	static inline int mmc_blk_readonly(struct mmc_card *card)
	304	{
	305	return mmc_card_readonly(card) \|\|
	306	!(card->csd.cmdclass & CCC_BLOCK_WRITE);
	307	}
	308
1da177e4 LT	309	static struct mmc_blk_data mmc_blk_alloc(struct mmc_card card)
	310	{
	311	struct mmc_blk_data *md;
	312	int devidx, ret;
	313
	314	devidx = find_first_zero_bit(dev_use, MMC_NUM_MINORS);
	315	if (devidx >= MMC_NUM_MINORS)
	316	return ERR_PTR(-ENOSPC);
	317	__set_bit(devidx, dev_use);
	318
	319	md = kmalloc(sizeof(struct mmc_blk_data), GFP_KERNEL);
a6f6c96b RK	320	if (!md) {
	321	ret = -ENOMEM;
	322	goto out;
	323	}
1da177e4	324
a6f6c96b	325	memset(md, 0, sizeof(struct mmc_blk_data));
1da177e4	326
a6f6c96b RK	327	/*
	328	* Set the read-only status based on the supported commands
	329	* and the write protect switch.
	330	*/
	331	md->read_only = mmc_blk_readonly(card);
1da177e4	332
a6f6c96b	333	/*
6fe9febb PO	334	* Both SD and MMC specifications state (although a bit
	335	* unclearly in the MMC case) that a block size of 512
	336	* bytes must always be supported by the card.
a6f6c96b	337	*/
6fe9febb	338	md->block_bits = 9;
1da177e4	339
a6f6c96b RK	340	md->disk = alloc_disk(1 << MMC_SHIFT);
	341	if (md->disk == NULL) {
	342	ret = -ENOMEM;
	343	goto err_kfree;
	344	}
1da177e4	345
a6f6c96b RK	346	spin_lock_init(&md->lock);
a6f6c96b RK	347	md->usage = 1;
1da177e4	348
a6f6c96b RK	349	ret = mmc_init_queue(&md->queue, card, &md->lock);
	350	if (ret)
	351	goto err_putdisk;
1da177e4	352
a6f6c96b RK	353	md->queue.prep_fn = mmc_blk_prep_rq;
	354	md->queue.issue_fn = mmc_blk_issue_rq;
	355	md->queue.data = md;
d2b18394	356
a6f6c96b RK	357	md->disk->major = major;
	358	md->disk->first_minor = devidx << MMC_SHIFT;
	359	md->disk->fops = &mmc_bdops;
	360	md->disk->private_data = md;
	361	md->disk->queue = md->queue.queue;
	362	md->disk->driverfs_dev = &card->dev;
	363
	364	/*
	365	* As discussed on lkml, GENHD_FL_REMOVABLE should:
	366	*
	367	* - be set for removable media with permanent block devices
	368	* - be unset for removable block devices with permanent media
	369	*
	370	* Since MMC block devices clearly fall under the second
	371	* case, we do not set GENHD_FL_REMOVABLE. Userspace
	372	* should use the block device creation/destruction hotplug
	373	* messages to tell when the card is present.
	374	*/
	375
	376	sprintf(md->disk->disk_name, "mmcblk%d", devidx);
a6f6c96b RK	377
	378	blk_queue_hardsect_size(md->queue.queue, 1 << md->block_bits);
	379
	380	/*
	381	* The CSD capacity field is in units of read_blkbits.
	382	* set_capacity takes units of 512 bytes.
	383	*/
	384	set_capacity(md->disk, card->csd.capacity << (card->csd.read_blkbits - 9));
1da177e4	385	return md;
a6f6c96b RK	386
	387	err_putdisk:
	388	put_disk(md->disk);
	389	err_kfree:
	390	kfree(md);
	391	out:
	392	return ERR_PTR(ret);
1da177e4 LT	393	}
	394
	395	static int
	396	mmc_blk_set_blksize(struct mmc_blk_data md, struct mmc_card card)
	397	{
	398	struct mmc_command cmd;
	399	int err;
	400
	401	mmc_card_claim_host(card);
	402	cmd.opcode = MMC_SET_BLOCKLEN;
d2b18394	403	cmd.arg = 1 << md->block_bits;
e9225176	404	cmd.flags = MMC_RSP_R1 \| MMC_CMD_AC;
1da177e4 LT	405	err = mmc_wait_for_cmd(card->host, &cmd, 5);
	406	mmc_card_release_host(card);
	407
	408	if (err) {
	409	printk(KERN_ERR "%s: unable to set block size to %d: %d\n",
	410	md->disk->disk_name, cmd.arg, err);
	411	return -EINVAL;
	412	}
	413
	414	return 0;
	415	}
	416
	417	static int mmc_blk_probe(struct mmc_card *card)
	418	{
	419	struct mmc_blk_data *md;
	420	int err;
	421
912490db PO	422	/*
	423	* Check that the card supports the command class(es) we need.
	424	*/
	425	if (!(card->csd.cmdclass & CCC_BLOCK_READ))
1da177e4 LT	426	return -ENODEV;
1da177e4 LT	427
1da177e4 LT	428	md = mmc_blk_alloc(card);
	429	if (IS_ERR(md))
	430	return PTR_ERR(md);
	431
	432	err = mmc_blk_set_blksize(md, card);
	433	if (err)
	434	goto out;
	435
51828abc	436	printk(KERN_INFO "%s: %s %s %lluKiB %s\n",
1da177e4	437	md->disk->disk_name, mmc_card_id(card), mmc_card_name(card),
51828abc AM	438	(unsigned long long)(get_capacity(md->disk) >> 1),
51828abc AM	439	md->read_only ? "(ro)" : "");
1da177e4 LT	440
	441	mmc_set_drvdata(card, md);
	442	add_disk(md->disk);
	443	return 0;
	444
	445	out:
	446	mmc_blk_put(md);
	447
	448	return err;
	449	}
	450
	451	static void mmc_blk_remove(struct mmc_card *card)
	452	{
	453	struct mmc_blk_data *md = mmc_get_drvdata(card);
	454
	455	if (md) {
	456	int devidx;
	457
	458	del_gendisk(md->disk);
	459
	460	/*
	461	* I think this is needed.
	462	*/
	463	md->disk->queue = NULL;
	464
	465	devidx = md->disk->first_minor >> MMC_SHIFT;
	466	__clear_bit(devidx, dev_use);
	467
	468	mmc_blk_put(md);
	469	}
	470	mmc_set_drvdata(card, NULL);
	471	}
	472
	473	#ifdef CONFIG_PM
	474	static int mmc_blk_suspend(struct mmc_card *card, pm_message_t state)
	475	{
	476	struct mmc_blk_data *md = mmc_get_drvdata(card);
	477
	478	if (md) {
	479	mmc_queue_suspend(&md->queue);
	480	}
	481	return 0;
	482	}
	483
	484	static int mmc_blk_resume(struct mmc_card *card)
	485	{
	486	struct mmc_blk_data *md = mmc_get_drvdata(card);
	487
	488	if (md) {
	489	mmc_blk_set_blksize(md, card);
	490	mmc_queue_resume(&md->queue);
	491	}
	492	return 0;
	493	}
	494	#else
	495	#define mmc_blk_suspend NULL
	496	#define mmc_blk_resume NULL
	497	#endif
	498
	499	static struct mmc_driver mmc_driver = {
	500	.drv = {
	501	.name = "mmcblk",
	502	},
	503	.probe = mmc_blk_probe,
504	.remove = mmc_blk_remove,
505	.suspend = mmc_blk_suspend,
506	.resume = mmc_blk_resume,
507	};
508
509	static int __init mmc_blk_init(void)
510	{
511	int res = -ENOMEM;
512
513	res = register_blkdev(major, "mmc");
514	if (res < 0) {
515	printk(KERN_WARNING "Unable to get major %d for MMC media: %d\n",
516	major, res);
517	goto out;
518	}
519	if (major == 0)
520	major = res;
521
1da177e4 LT	522	return mmc_register_driver(&mmc_driver);
	523
	524	out:
	525	return res;
	526	}
	527
	528	static void __exit mmc_blk_exit(void)
	529	{
	530	mmc_unregister_driver(&mmc_driver);
1da177e4 LT	531	unregister_blkdev(major, "mmc");
	532	}
	533
	534	module_init(mmc_blk_init);
	535	module_exit(mmc_blk_exit);
	536
	537	MODULE_LICENSE("GPL");
	538	MODULE_DESCRIPTION("Multimedia Card (MMC) block device driver");
	539
	540	module_param(major, int, 0444);
	541	MODULE_PARM_DESC(major, "specify the major device number for MMC block driver");