[linux-2.6-block.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/devfs_fs_kernel.h>

#include <linux/mmc/card.h>
#include <linux/mmc/protocol.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 DECLARE_MUTEX(open_lock);

static struct mmc_blk_data *mmc_blk_get(struct gendisk *disk)
{
	struct mmc_blk_data *md;

	down(&open_lock);
	md = disk->private_data;
	if (md && md->usage == 0)
		md = NULL;
	if (md)
		md->usage++;
	up(&open_lock);

	return md;
}

static void mmc_blk_put(struct mmc_blk_data *md)
{
	down(&open_lock);
	md->usage--;
	if (md->usage == 0) {
		put_disk(md->disk);
		mmc_cleanup_queue(&md->queue);
		kfree(md);
	}
	up(&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;

		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;
		brq.data.timeout_ns = card->csd.tacc_ns * 10;
		brq.data.timeout_clks = card->csd.tacc_clks * 10;
		brq.data.blksz_bits = 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;

		if (rq_data_dir(req) == READ) {
			brq.cmd.opcode = brq.data.blocks > 1 ? MMC_READ_MULTIPLE_BLOCK : MMC_READ_SINGLE_BLOCK;
			brq.data.flags |= MMC_DATA_READ;
		} else {
			brq.cmd.opcode = MMC_WRITE_BLOCK;
			brq.data.flags |= MMC_DATA_WRITE;
			brq.data.blocks = 1;
		}

		if (brq.data.blocks > 1) {
			brq.data.flags |= MMC_DATA_MULTI;
			brq.mrq.stop = &brq.stop;
		} else {
			brq.mrq.stop = NULL;
		}

		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;
			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);

	/*
	 * Figure out a workable block size.  MMC cards have:
	 *  - two block sizes, one for read and one for write.
	 *  - may support partial reads and/or writes
	 *    (allows block sizes smaller than specified)
	 */
	md->block_bits = card->csd.read_blkbits;
	if (card->csd.write_blkbits != card->csd.read_blkbits) {
		if (card->csd.write_blkbits < card->csd.read_blkbits &&
		    card->csd.read_partial) {
			/*
			 * write block size is smaller than read block
			 * size, but we support partial reads, so choose
			 * the smaller write block size.
			 */
			md->block_bits = card->csd.write_blkbits;
		} else if (card->csd.write_blkbits > card->csd.read_blkbits &&
			   card->csd.write_partial) {
			/*
			 * read block size is smaller than write block
			 * size, but we support partial writes.  Use read
			 * block size.
			 */
		} else {
			/*
			 * We don't support this configuration for writes.
			 */
			printk(KERN_ERR "%s: unable to select block size for "
				"writing (rb%u wb%u rp%u wp%u)\n",
				md->disk->disk_name,
				1 << card->csd.read_blkbits,
				1 << card->csd.write_blkbits,
				card->csd.read_partial,
				card->csd.write_partial);
			md->read_only = 1;
		}
	}

	/*
	 * Refuse to allow block sizes smaller than 512 bytes.
	 */
	if (md->block_bits < 9) {
		printk(KERN_ERR "%s: unable to support block size %u\n",
			mmc_card_id(card), 1 << md->block_bits);
		ret = -EINVAL;
		goto err_kfree;
	}

	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);
	sprintf(md->disk->devfs_name, "mmc/blk%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;
	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 %luKiB %s\n",
		md->disk->disk_name, mmc_card_id(card), mmc_card_name(card),
		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;

	devfs_mk_dir("mmc");
	return mmc_register_driver(&mmc_driver);

 out:
	return res;
}

static void __exit mmc_blk_exit(void)
{
	mmc_unregister_driver(&mmc_driver);
	devfs_remove("mmc");
	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>
	30	#include <linux/devfs_fs_kernel.h>
	31
	32	#include <linux/mmc/card.h>
	33	#include <linux/mmc/protocol.h>
	34
	35	#include <asm/system.h>
	36	#include <asm/uaccess.h>
	37
	38	#include "mmc_queue.h"
	39
	40	/*
	41	* max 8 partitions per card
	42	*/
	43	#define MMC_SHIFT 3
	44
	45	static int major;
	46
	47	/*
	48	* There is one mmc_blk_data per slot.
	49	*/
	50	struct mmc_blk_data {
	51	spinlock_t lock;
	52	struct gendisk *disk;
	53	struct mmc_queue queue;
	54
	55	unsigned int usage;
	56	unsigned int block_bits;
a6f6c96b	57	unsigned int read_only;
1da177e4 LT	58	};
	59
	60	static DECLARE_MUTEX(open_lock);
	61
	62	static struct mmc_blk_data mmc_blk_get(struct gendisk disk)
	63	{
	64	struct mmc_blk_data *md;
	65
	66	down(&open_lock);
	67	md = disk->private_data;
	68	if (md && md->usage == 0)
	69	md = NULL;
	70	if (md)
	71	md->usage++;
	72	up(&open_lock);
	73
	74	return md;
	75	}
	76
	77	static void mmc_blk_put(struct mmc_blk_data *md)
	78	{
	79	down(&open_lock);
	80	md->usage--;
	81	if (md->usage == 0) {
	82	put_disk(md->disk);
	83	mmc_cleanup_queue(&md->queue);
	84	kfree(md);
	85	}
	86	up(&open_lock);
	87	}
	88
	89	static int mmc_blk_open(struct inode inode, struct file filp)
	90	{
	91	struct mmc_blk_data *md;
	92	int ret = -ENXIO;
	93
	94	md = mmc_blk_get(inode->i_bdev->bd_disk);
	95	if (md) {
	96	if (md->usage == 2)
	97	check_disk_change(inode->i_bdev);
	98	ret = 0;
a00fc090	99
a6f6c96b	100	if ((filp->f_mode & FMODE_WRITE) && md->read_only)
a00fc090	101	ret = -EROFS;
1da177e4 LT	102	}
	103
	104	return ret;
	105	}
	106
	107	static int mmc_blk_release(struct inode inode, struct file filp)
	108	{
	109	struct mmc_blk_data *md = inode->i_bdev->bd_disk->private_data;
	110
	111	mmc_blk_put(md);
	112	return 0;
	113	}
	114
	115	static int
a885c8c4	116	mmc_blk_getgeo(struct block_device bdev, struct hd_geometry geo)
1da177e4	117	{
a885c8c4 CH	118	geo->cylinders = get_capacity(bdev->bd_disk) / (4 * 16);
	119	geo->heads = 4;
	120	geo->sectors = 16;
	121	return 0;
1da177e4 LT	122	}
	123
	124	static struct block_device_operations mmc_bdops = {
	125	.open = mmc_blk_open,
	126	.release = mmc_blk_release,
a885c8c4	127	.getgeo = mmc_blk_getgeo,
1da177e4 LT	128	.owner = THIS_MODULE,
	129	};
	130
	131	struct mmc_blk_request {
	132	struct mmc_request mrq;
	133	struct mmc_command cmd;
	134	struct mmc_command stop;
	135	struct mmc_data data;
	136	};
	137
	138	static int mmc_blk_prep_rq(struct mmc_queue mq, struct request req)
	139	{
	140	struct mmc_blk_data *md = mq->data;
	141	int stat = BLKPREP_OK;
	142
	143	/*
	144	* If we have no device, we haven't finished initialising.
	145	*/
	146	if (!md \|\| !mq->card) {
	147	printk(KERN_ERR "%s: killing request - no device/host\n",
	148	req->rq_disk->disk_name);
	149	stat = BLKPREP_KILL;
	150	}
	151
	152	return stat;
	153	}
	154
	155	static int mmc_blk_issue_rq(struct mmc_queue mq, struct request req)
	156	{
	157	struct mmc_blk_data *md = mq->data;
	158	struct mmc_card *card = md->queue.card;
	159	int ret;
	160
	161	if (mmc_card_claim_host(card))
	162	goto cmd_err;
	163
	164	do {
	165	struct mmc_blk_request brq;
	166	struct mmc_command cmd;
	167
	168	memset(&brq, 0, sizeof(struct mmc_blk_request));
	169	brq.mrq.cmd = &brq.cmd;
	170	brq.mrq.data = &brq.data;
	171
	172	brq.cmd.arg = req->sector << 9;
	173	brq.cmd.flags = MMC_RSP_R1;
	174	brq.data.timeout_ns = card->csd.tacc_ns * 10;
	175	brq.data.timeout_clks = card->csd.tacc_clks * 10;
	176	brq.data.blksz_bits = md->block_bits;
	177	brq.data.blocks = req->nr_sectors >> (md->block_bits - 9);
	178	brq.stop.opcode = MMC_STOP_TRANSMISSION;
	179	brq.stop.arg = 0;
	180	brq.stop.flags = MMC_RSP_R1B;
	181
	182	if (rq_data_dir(req) == READ) {
	183	brq.cmd.opcode = brq.data.blocks > 1 ? MMC_READ_MULTIPLE_BLOCK : MMC_READ_SINGLE_BLOCK;
	184	brq.data.flags \|= MMC_DATA_READ;
	185	} else {
	186	brq.cmd.opcode = MMC_WRITE_BLOCK;
1da177e4 LT	187	brq.data.flags \|= MMC_DATA_WRITE;
	188	brq.data.blocks = 1;
	189	}
788ee7b0 RK	190
	191	if (brq.data.blocks > 1) {
	192	brq.data.flags \|= MMC_DATA_MULTI;
	193	brq.mrq.stop = &brq.stop;
	194	} else {
	195	brq.mrq.stop = NULL;
	196	}
1da177e4 LT	197
	198	brq.data.sg = mq->sg;
	199	brq.data.sg_len = blk_rq_map_sg(req->q, req, brq.data.sg);
	200
	201	mmc_wait_for_req(card->host, &brq.mrq);
	202	if (brq.cmd.error) {
	203	printk(KERN_ERR "%s: error %d sending read/write command\n",
	204	req->rq_disk->disk_name, brq.cmd.error);
	205	goto cmd_err;
	206	}
	207
	208	if (brq.data.error) {
	209	printk(KERN_ERR "%s: error %d transferring data\n",
	210	req->rq_disk->disk_name, brq.data.error);
	211	goto cmd_err;
	212	}
	213
	214	if (brq.stop.error) {
	215	printk(KERN_ERR "%s: error %d sending stop command\n",
	216	req->rq_disk->disk_name, brq.stop.error);
	217	goto cmd_err;
	218	}
	219
	220	do {
	221	int err;
	222
	223	cmd.opcode = MMC_SEND_STATUS;
	224	cmd.arg = card->rca << 16;
	225	cmd.flags = MMC_RSP_R1;
	226	err = mmc_wait_for_cmd(card->host, &cmd, 5);
	227	if (err) {
	228	printk(KERN_ERR "%s: error %d requesting status\n",
	229	req->rq_disk->disk_name, err);
	230	goto cmd_err;
	231	}
	232	} while (!(cmd.resp[0] & R1_READY_FOR_DATA));
	233
	234	#if 0
	235	if (cmd.resp[0] & ~0x00000900)
	236	printk(KERN_ERR "%s: status = %08x\n",
	237	req->rq_disk->disk_name, cmd.resp[0]);
	238	if (mmc_decode_status(cmd.resp))
	239	goto cmd_err;
	240	#endif
	241
	242	/*
	243	* A block was successfully transferred.
	244	*/
	245	spin_lock_irq(&md->lock);
	246	ret = end_that_request_chunk(req, 1, brq.data.bytes_xfered);
	247	if (!ret) {
	248	/*
	249	* The whole request completed successfully.
	250	*/
	251	add_disk_randomness(req->rq_disk);
	252	blkdev_dequeue_request(req);
8ffdc655	253	end_that_request_last(req, 1);
1da177e4 LT	254	}
	255	spin_unlock_irq(&md->lock);
	256	} while (ret);
	257
	258	mmc_card_release_host(card);
	259
	260	return 1;
	261
	262	cmd_err:
	263	mmc_card_release_host(card);
	264
	265	/*
	266	* This is a little draconian, but until we get proper
	267	* error handling sorted out here, its the best we can
	268	* do - especially as some hosts have no idea how much
	269	* data was transferred before the error occurred.
	270	*/
	271	spin_lock_irq(&md->lock);
	272	do {
	273	ret = end_that_request_chunk(req, 0,
	274	req->current_nr_sectors << 9);
	275	} while (ret);
	276
	277	add_disk_randomness(req->rq_disk);
	278	blkdev_dequeue_request(req);
8ffdc655	279	end_that_request_last(req, 0);
1da177e4 LT	280	spin_unlock_irq(&md->lock);
	281
	282	return 0;
	283	}
	284
	285	#define MMC_NUM_MINORS (256 >> MMC_SHIFT)
	286
	287	static unsigned long dev_use[MMC_NUM_MINORS/(8*sizeof(unsigned long))];
	288
a6f6c96b RK	289	static inline int mmc_blk_readonly(struct mmc_card *card)
	290	{
	291	return mmc_card_readonly(card) \|\|
	292	!(card->csd.cmdclass & CCC_BLOCK_WRITE);
	293	}
	294
1da177e4 LT	295	static struct mmc_blk_data mmc_blk_alloc(struct mmc_card card)
	296	{
	297	struct mmc_blk_data *md;
	298	int devidx, ret;
	299
	300	devidx = find_first_zero_bit(dev_use, MMC_NUM_MINORS);
	301	if (devidx >= MMC_NUM_MINORS)
	302	return ERR_PTR(-ENOSPC);
	303	__set_bit(devidx, dev_use);
	304
	305	md = kmalloc(sizeof(struct mmc_blk_data), GFP_KERNEL);
a6f6c96b RK	306	if (!md) {
	307	ret = -ENOMEM;
	308	goto out;
	309	}
1da177e4	310
a6f6c96b	311	memset(md, 0, sizeof(struct mmc_blk_data));
1da177e4	312
a6f6c96b RK	313	/*
	314	* Set the read-only status based on the supported commands
	315	* and the write protect switch.
	316	*/
	317	md->read_only = mmc_blk_readonly(card);
1da177e4	318
a6f6c96b RK	319	/*
	320	* Figure out a workable block size. MMC cards have:
	321	* - two block sizes, one for read and one for write.
	322	* - may support partial reads and/or writes
	323	* (allows block sizes smaller than specified)
	324	*/
	325	md->block_bits = card->csd.read_blkbits;
	326	if (card->csd.write_blkbits != card->csd.read_blkbits) {
	327	if (card->csd.write_blkbits < card->csd.read_blkbits &&
	328	card->csd.read_partial) {
	329	/*
	330	* write block size is smaller than read block
	331	* size, but we support partial reads, so choose
	332	* the smaller write block size.
	333	*/
	334	md->block_bits = card->csd.write_blkbits;
	335	} else if (card->csd.write_blkbits > card->csd.read_blkbits &&
	336	card->csd.write_partial) {
	337	/*
	338	* read block size is smaller than write block
	339	* size, but we support partial writes. Use read
	340	* block size.
	341	*/
	342	} else {
	343	/*
	344	* We don't support this configuration for writes.
	345	*/
	346	printk(KERN_ERR "%s: unable to select block size for "
	347	"writing (rb%u wb%u rp%u wp%u)\n",
	348	md->disk->disk_name,
	349	1 << card->csd.read_blkbits,
	350	1 << card->csd.write_blkbits,
	351	card->csd.read_partial,
	352	card->csd.write_partial);
	353	md->read_only = 1;
1da177e4	354	}
a6f6c96b	355	}
1da177e4	356
a6f6c96b RK	357	/*
	358	* Refuse to allow block sizes smaller than 512 bytes.
	359	*/
	360	if (md->block_bits < 9) {
	361	printk(KERN_ERR "%s: unable to support block size %u\n",
	362	mmc_card_id(card), 1 << md->block_bits);
	363	ret = -EINVAL;
	364	goto err_kfree;
	365	}
1da177e4	366
a6f6c96b RK	367	md->disk = alloc_disk(1 << MMC_SHIFT);
	368	if (md->disk == NULL) {
	369	ret = -ENOMEM;
	370	goto err_kfree;
	371	}
1da177e4	372
a6f6c96b RK	373	spin_lock_init(&md->lock);
a6f6c96b RK	374	md->usage = 1;
1da177e4	375
a6f6c96b RK	376	ret = mmc_init_queue(&md->queue, card, &md->lock);
	377	if (ret)
	378	goto err_putdisk;
1da177e4	379
a6f6c96b RK	380	md->queue.prep_fn = mmc_blk_prep_rq;
	381	md->queue.issue_fn = mmc_blk_issue_rq;
	382	md->queue.data = md;
d2b18394	383
a6f6c96b RK	384	md->disk->major = major;
	385	md->disk->first_minor = devidx << MMC_SHIFT;
	386	md->disk->fops = &mmc_bdops;
	387	md->disk->private_data = md;
	388	md->disk->queue = md->queue.queue;
	389	md->disk->driverfs_dev = &card->dev;
	390
	391	/*
	392	* As discussed on lkml, GENHD_FL_REMOVABLE should:
	393	*
	394	* - be set for removable media with permanent block devices
	395	* - be unset for removable block devices with permanent media
	396	*
	397	* Since MMC block devices clearly fall under the second
	398	* case, we do not set GENHD_FL_REMOVABLE. Userspace
	399	* should use the block device creation/destruction hotplug
	400	* messages to tell when the card is present.
	401	*/
	402
	403	sprintf(md->disk->disk_name, "mmcblk%d", devidx);
	404	sprintf(md->disk->devfs_name, "mmc/blk%d", devidx);
	405
	406	blk_queue_hardsect_size(md->queue.queue, 1 << md->block_bits);
	407
	408	/*
	409	* The CSD capacity field is in units of read_blkbits.
	410	* set_capacity takes units of 512 bytes.
	411	*/
	412	set_capacity(md->disk, card->csd.capacity << (card->csd.read_blkbits - 9));
1da177e4	413	return md;
a6f6c96b RK	414
	415	err_putdisk:
	416	put_disk(md->disk);
	417	err_kfree:
	418	kfree(md);
	419	out:
	420	return ERR_PTR(ret);
1da177e4 LT	421	}
	422
	423	static int
	424	mmc_blk_set_blksize(struct mmc_blk_data md, struct mmc_card card)
	425	{
	426	struct mmc_command cmd;
	427	int err;
	428
	429	mmc_card_claim_host(card);
	430	cmd.opcode = MMC_SET_BLOCKLEN;
d2b18394	431	cmd.arg = 1 << md->block_bits;
1da177e4 LT	432	cmd.flags = MMC_RSP_R1;
	433	err = mmc_wait_for_cmd(card->host, &cmd, 5);
	434	mmc_card_release_host(card);
	435
	436	if (err) {
	437	printk(KERN_ERR "%s: unable to set block size to %d: %d\n",
	438	md->disk->disk_name, cmd.arg, err);
	439	return -EINVAL;
	440	}
	441
	442	return 0;
	443	}
	444
	445	static int mmc_blk_probe(struct mmc_card *card)
	446	{
	447	struct mmc_blk_data *md;
	448	int err;
	449
912490db PO	450	/*
	451	* Check that the card supports the command class(es) we need.
	452	*/
	453	if (!(card->csd.cmdclass & CCC_BLOCK_READ))
1da177e4 LT	454	return -ENODEV;
1da177e4 LT	455
1da177e4 LT	456	md = mmc_blk_alloc(card);
	457	if (IS_ERR(md))
	458	return PTR_ERR(md);
	459
	460	err = mmc_blk_set_blksize(md, card);
	461	if (err)
	462	goto out;
	463
d2b18394	464	printk(KERN_INFO "%s: %s %s %luKiB %s\n",
1da177e4	465	md->disk->disk_name, mmc_card_id(card), mmc_card_name(card),
a6f6c96b	466	get_capacity(md->disk) >> 1, md->read_only ? "(ro)" : "");
1da177e4 LT	467
	468	mmc_set_drvdata(card, md);
	469	add_disk(md->disk);
	470	return 0;
	471
	472	out:
	473	mmc_blk_put(md);
	474
	475	return err;
	476	}
	477
	478	static void mmc_blk_remove(struct mmc_card *card)
	479	{
	480	struct mmc_blk_data *md = mmc_get_drvdata(card);
	481
	482	if (md) {
	483	int devidx;
	484
	485	del_gendisk(md->disk);
	486
	487	/*
	488	* I think this is needed.
	489	*/
	490	md->disk->queue = NULL;
	491
	492	devidx = md->disk->first_minor >> MMC_SHIFT;
	493	__clear_bit(devidx, dev_use);
	494
	495	mmc_blk_put(md);
	496	}
	497	mmc_set_drvdata(card, NULL);
	498	}
	499
	500	#ifdef CONFIG_PM
	501	static int mmc_blk_suspend(struct mmc_card *card, pm_message_t state)
	502	{
	503	struct mmc_blk_data *md = mmc_get_drvdata(card);
	504
	505	if (md) {
	506	mmc_queue_suspend(&md->queue);
	507	}
	508	return 0;
	509	}
	510
	511	static int mmc_blk_resume(struct mmc_card *card)
	512	{
	513	struct mmc_blk_data *md = mmc_get_drvdata(card);
	514
	515	if (md) {
	516	mmc_blk_set_blksize(md, card);
	517	mmc_queue_resume(&md->queue);
	518	}
	519	return 0;
	520	}
	521	#else
	522	#define mmc_blk_suspend NULL
	523	#define mmc_blk_resume NULL
	524	#endif
	525
	526	static struct mmc_driver mmc_driver = {
	527	.drv = {
	528	.name = "mmcblk",
	529	},
	530	.probe = mmc_blk_probe,
531	.remove = mmc_blk_remove,
532	.suspend = mmc_blk_suspend,
533	.resume = mmc_blk_resume,
534	};
535
536	static int __init mmc_blk_init(void)
537	{
538	int res = -ENOMEM;
539
540	res = register_blkdev(major, "mmc");
541	if (res < 0) {
542	printk(KERN_WARNING "Unable to get major %d for MMC media: %d\n",
543	major, res);
544	goto out;
545	}
546	if (major == 0)
547	major = res;
548
549	devfs_mk_dir("mmc");
550	return mmc_register_driver(&mmc_driver);
551
552	out:
553	return res;
554	}
555
556	static void __exit mmc_blk_exit(void)
557	{
558	mmc_unregister_driver(&mmc_driver);
559	devfs_remove("mmc");
560	unregister_blkdev(major, "mmc");
561	}
562
563	module_init(mmc_blk_init);
564	module_exit(mmc_blk_exit);
565
566	MODULE_LICENSE("GPL");
567	MODULE_DESCRIPTION("Multimedia Card (MMC) block device driver");
568
569	module_param(major, int, 0444);
570	MODULE_PARM_DESC(major, "specify the major device number for MMC block driver");