[mirror_ubuntu-hirsute-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 <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;

		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_bits = md->block_bits;
		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 (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 | 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);

	/*
	 * 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",
				mmc_card_id(card),
				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);

	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 LT	34	#include <linux/mmc/protocol.h>
	35
	36	#include <asm/system.h>
	37	#include <asm/uaccess.h>
	38
	39	#include "mmc_queue.h"
	40
	41	/*
	42	* max 8 partitions per card
	43	*/
	44	#define MMC_SHIFT 3
	45
	46	static int major;
	47
	48	/*
	49	* There is one mmc_blk_data per slot.
	50	*/
	51	struct mmc_blk_data {
	52	spinlock_t lock;
	53	struct gendisk *disk;
	54	struct mmc_queue queue;
	55
	56	unsigned int usage;
	57	unsigned int block_bits;
a6f6c96b	58	unsigned int read_only;
1da177e4 LT	59	};
1da177e4 LT	60
a621aaed	61	static DEFINE_MUTEX(open_lock);
1da177e4 LT	62
	63	static struct mmc_blk_data mmc_blk_get(struct gendisk disk)
	64	{
	65	struct mmc_blk_data *md;
	66
a621aaed	67	mutex_lock(&open_lock);
1da177e4 LT	68	md = disk->private_data;
	69	if (md && md->usage == 0)
	70	md = NULL;
	71	if (md)
	72	md->usage++;
a621aaed	73	mutex_unlock(&open_lock);
1da177e4 LT	74
	75	return md;
	76	}
	77
	78	static void mmc_blk_put(struct mmc_blk_data *md)
	79	{
a621aaed	80	mutex_lock(&open_lock);
1da177e4 LT	81	md->usage--;
	82	if (md->usage == 0) {
	83	put_disk(md->disk);
	84	mmc_cleanup_queue(&md->queue);
	85	kfree(md);
	86	}
a621aaed	87	mutex_unlock(&open_lock);
1da177e4 LT	88	}
	89
	90	static int mmc_blk_open(struct inode inode, struct file filp)
	91	{
	92	struct mmc_blk_data *md;
	93	int ret = -ENXIO;
	94
	95	md = mmc_blk_get(inode->i_bdev->bd_disk);
	96	if (md) {
	97	if (md->usage == 2)
	98	check_disk_change(inode->i_bdev);
	99	ret = 0;
a00fc090	100
a6f6c96b	101	if ((filp->f_mode & FMODE_WRITE) && md->read_only)
a00fc090	102	ret = -EROFS;
1da177e4 LT	103	}
	104
	105	return ret;
	106	}
	107
	108	static int mmc_blk_release(struct inode inode, struct file filp)
	109	{
	110	struct mmc_blk_data *md = inode->i_bdev->bd_disk->private_data;
	111
	112	mmc_blk_put(md);
	113	return 0;
	114	}
	115
	116	static int
a885c8c4	117	mmc_blk_getgeo(struct block_device bdev, struct hd_geometry geo)
1da177e4	118	{
a885c8c4 CH	119	geo->cylinders = get_capacity(bdev->bd_disk) / (4 * 16);
	120	geo->heads = 4;
	121	geo->sectors = 16;
	122	return 0;
1da177e4 LT	123	}
	124
	125	static struct block_device_operations mmc_bdops = {
	126	.open = mmc_blk_open,
	127	.release = mmc_blk_release,
a885c8c4	128	.getgeo = mmc_blk_getgeo,
1da177e4 LT	129	.owner = THIS_MODULE,
	130	};
	131
	132	struct mmc_blk_request {
	133	struct mmc_request mrq;
	134	struct mmc_command cmd;
	135	struct mmc_command stop;
	136	struct mmc_data data;
	137	};
	138
	139	static int mmc_blk_prep_rq(struct mmc_queue mq, struct request req)
	140	{
	141	struct mmc_blk_data *md = mq->data;
	142	int stat = BLKPREP_OK;
	143
	144	/*
	145	* If we have no device, we haven't finished initialising.
	146	*/
	147	if (!md \|\| !mq->card) {
	148	printk(KERN_ERR "%s: killing request - no device/host\n",
	149	req->rq_disk->disk_name);
	150	stat = BLKPREP_KILL;
	151	}
	152
	153	return stat;
	154	}
	155
	156	static int mmc_blk_issue_rq(struct mmc_queue mq, struct request req)
	157	{
	158	struct mmc_blk_data *md = mq->data;
	159	struct mmc_card *card = md->queue.card;
	160	int ret;
	161
	162	if (mmc_card_claim_host(card))
	163	goto cmd_err;
	164
	165	do {
	166	struct mmc_blk_request brq;
	167	struct mmc_command cmd;
	168
	169	memset(&brq, 0, sizeof(struct mmc_blk_request));
	170	brq.mrq.cmd = &brq.cmd;
	171	brq.mrq.data = &brq.data;
	172
	173	brq.cmd.arg = req->sector << 9;
e9225176	174	brq.cmd.flags = MMC_RSP_R1 \| MMC_CMD_ADTC;
1da177e4	175	brq.data.blksz_bits = md->block_bits;
2c171bf1	176	brq.data.blksz = 1 << md->block_bits;
1da177e4 LT	177	brq.data.blocks = req->nr_sectors >> (md->block_bits - 9);
	178	brq.stop.opcode = MMC_STOP_TRANSMISSION;
	179	brq.stop.arg = 0;
e9225176	180	brq.stop.flags = MMC_RSP_R1B \| MMC_CMD_AC;
1da177e4	181
d773d725	182	mmc_set_data_timeout(&brq.data, card, rq_data_dir(req) != READ);
385e3227	183
1da177e4 LT	184	if (rq_data_dir(req) == READ) {
	185	brq.cmd.opcode = brq.data.blocks > 1 ? MMC_READ_MULTIPLE_BLOCK : MMC_READ_SINGLE_BLOCK;
	186	brq.data.flags \|= MMC_DATA_READ;
	187	} else {
	188	brq.cmd.opcode = MMC_WRITE_BLOCK;
1da177e4 LT	189	brq.data.flags \|= MMC_DATA_WRITE;
	190	brq.data.blocks = 1;
	191	}
788ee7b0 RK	192
	193	if (brq.data.blocks > 1) {
	194	brq.data.flags \|= MMC_DATA_MULTI;
	195	brq.mrq.stop = &brq.stop;
	196	} else {
	197	brq.mrq.stop = NULL;
	198	}
1da177e4 LT	199
	200	brq.data.sg = mq->sg;
	201	brq.data.sg_len = blk_rq_map_sg(req->q, req, brq.data.sg);
	202
	203	mmc_wait_for_req(card->host, &brq.mrq);
	204	if (brq.cmd.error) {
	205	printk(KERN_ERR "%s: error %d sending read/write command\n",
	206	req->rq_disk->disk_name, brq.cmd.error);
	207	goto cmd_err;
	208	}
	209
	210	if (brq.data.error) {
	211	printk(KERN_ERR "%s: error %d transferring data\n",
	212	req->rq_disk->disk_name, brq.data.error);
	213	goto cmd_err;
	214	}
	215
	216	if (brq.stop.error) {
	217	printk(KERN_ERR "%s: error %d sending stop command\n",
	218	req->rq_disk->disk_name, brq.stop.error);
	219	goto cmd_err;
	220	}
	221
	222	do {
	223	int err;
	224
	225	cmd.opcode = MMC_SEND_STATUS;
	226	cmd.arg = card->rca << 16;
e9225176	227	cmd.flags = MMC_RSP_R1 \| MMC_CMD_AC;
1da177e4 LT	228	err = mmc_wait_for_cmd(card->host, &cmd, 5);
	229	if (err) {
	230	printk(KERN_ERR "%s: error %d requesting status\n",
	231	req->rq_disk->disk_name, err);
	232	goto cmd_err;
	233	}
	234	} while (!(cmd.resp[0] & R1_READY_FOR_DATA));
	235
	236	#if 0
	237	if (cmd.resp[0] & ~0x00000900)
	238	printk(KERN_ERR "%s: status = %08x\n",
	239	req->rq_disk->disk_name, cmd.resp[0]);
	240	if (mmc_decode_status(cmd.resp))
	241	goto cmd_err;
	242	#endif
	243
	244	/*
	245	* A block was successfully transferred.
	246	*/
	247	spin_lock_irq(&md->lock);
	248	ret = end_that_request_chunk(req, 1, brq.data.bytes_xfered);
	249	if (!ret) {
	250	/*
	251	* The whole request completed successfully.
	252	*/
	253	add_disk_randomness(req->rq_disk);
	254	blkdev_dequeue_request(req);
8ffdc655	255	end_that_request_last(req, 1);
1da177e4 LT	256	}
	257	spin_unlock_irq(&md->lock);
	258	} while (ret);
	259
	260	mmc_card_release_host(card);
	261
	262	return 1;
	263
	264	cmd_err:
	265	mmc_card_release_host(card);
	266
	267	/*
	268	* This is a little draconian, but until we get proper
	269	* error handling sorted out here, its the best we can
	270	* do - especially as some hosts have no idea how much
	271	* data was transferred before the error occurred.
	272	*/
	273	spin_lock_irq(&md->lock);
	274	do {
	275	ret = end_that_request_chunk(req, 0,
	276	req->current_nr_sectors << 9);
	277	} while (ret);
	278
	279	add_disk_randomness(req->rq_disk);
	280	blkdev_dequeue_request(req);
8ffdc655	281	end_that_request_last(req, 0);
1da177e4 LT	282	spin_unlock_irq(&md->lock);
	283
	284	return 0;
	285	}
	286
	287	#define MMC_NUM_MINORS (256 >> MMC_SHIFT)
	288
	289	static unsigned long dev_use[MMC_NUM_MINORS/(8*sizeof(unsigned long))];
	290
a6f6c96b RK	291	static inline int mmc_blk_readonly(struct mmc_card *card)
	292	{
	293	return mmc_card_readonly(card) \|\|
	294	!(card->csd.cmdclass & CCC_BLOCK_WRITE);
	295	}
	296
1da177e4 LT	297	static struct mmc_blk_data mmc_blk_alloc(struct mmc_card card)
	298	{
	299	struct mmc_blk_data *md;
	300	int devidx, ret;
	301
	302	devidx = find_first_zero_bit(dev_use, MMC_NUM_MINORS);
	303	if (devidx >= MMC_NUM_MINORS)
	304	return ERR_PTR(-ENOSPC);
	305	__set_bit(devidx, dev_use);
	306
	307	md = kmalloc(sizeof(struct mmc_blk_data), GFP_KERNEL);
a6f6c96b RK	308	if (!md) {
	309	ret = -ENOMEM;
	310	goto out;
	311	}
1da177e4	312
a6f6c96b	313	memset(md, 0, sizeof(struct mmc_blk_data));
1da177e4	314
a6f6c96b RK	315	/*
	316	* Set the read-only status based on the supported commands
	317	* and the write protect switch.
	318	*/
	319	md->read_only = mmc_blk_readonly(card);
1da177e4	320
a6f6c96b RK	321	/*
	322	* Figure out a workable block size. MMC cards have:
	323	* - two block sizes, one for read and one for write.
	324	* - may support partial reads and/or writes
	325	* (allows block sizes smaller than specified)
	326	*/
	327	md->block_bits = card->csd.read_blkbits;
	328	if (card->csd.write_blkbits != card->csd.read_blkbits) {
	329	if (card->csd.write_blkbits < card->csd.read_blkbits &&
	330	card->csd.read_partial) {
	331	/*
	332	* write block size is smaller than read block
	333	* size, but we support partial reads, so choose
	334	* the smaller write block size.
	335	*/
	336	md->block_bits = card->csd.write_blkbits;
	337	} else if (card->csd.write_blkbits > card->csd.read_blkbits &&
	338	card->csd.write_partial) {
	339	/*
	340	* read block size is smaller than write block
	341	* size, but we support partial writes. Use read
	342	* block size.
	343	*/
	344	} else {
	345	/*
	346	* We don't support this configuration for writes.
	347	*/
	348	printk(KERN_ERR "%s: unable to select block size for "
	349	"writing (rb%u wb%u rp%u wp%u)\n",
51c40327	350	mmc_card_id(card),
a6f6c96b RK	351	1 << card->csd.read_blkbits,
	352	1 << card->csd.write_blkbits,
	353	card->csd.read_partial,
	354	card->csd.write_partial);
	355	md->read_only = 1;
1da177e4	356	}
a6f6c96b	357	}
1da177e4	358
a6f6c96b RK	359	/*
	360	* Refuse to allow block sizes smaller than 512 bytes.
	361	*/
	362	if (md->block_bits < 9) {
	363	printk(KERN_ERR "%s: unable to support block size %u\n",
	364	mmc_card_id(card), 1 << md->block_bits);
	365	ret = -EINVAL;
	366	goto err_kfree;
	367	}
1da177e4	368
a6f6c96b RK	369	md->disk = alloc_disk(1 << MMC_SHIFT);
	370	if (md->disk == NULL) {
	371	ret = -ENOMEM;
	372	goto err_kfree;
	373	}
1da177e4	374
a6f6c96b RK	375	spin_lock_init(&md->lock);
a6f6c96b RK	376	md->usage = 1;
1da177e4	377
a6f6c96b RK	378	ret = mmc_init_queue(&md->queue, card, &md->lock);
	379	if (ret)
	380	goto err_putdisk;
1da177e4	381
a6f6c96b RK	382	md->queue.prep_fn = mmc_blk_prep_rq;
	383	md->queue.issue_fn = mmc_blk_issue_rq;
	384	md->queue.data = md;
d2b18394	385
a6f6c96b RK	386	md->disk->major = major;
	387	md->disk->first_minor = devidx << MMC_SHIFT;
	388	md->disk->fops = &mmc_bdops;
	389	md->disk->private_data = md;
	390	md->disk->queue = md->queue.queue;
	391	md->disk->driverfs_dev = &card->dev;
	392
	393	/*
	394	* As discussed on lkml, GENHD_FL_REMOVABLE should:
	395	*
	396	* - be set for removable media with permanent block devices
	397	* - be unset for removable block devices with permanent media
	398	*
	399	* Since MMC block devices clearly fall under the second
	400	* case, we do not set GENHD_FL_REMOVABLE. Userspace
	401	* should use the block device creation/destruction hotplug
	402	* messages to tell when the card is present.
	403	*/
	404
	405	sprintf(md->disk->disk_name, "mmcblk%d", devidx);
a6f6c96b RK	406
	407	blk_queue_hardsect_size(md->queue.queue, 1 << md->block_bits);
	408
	409	/*
	410	* The CSD capacity field is in units of read_blkbits.
	411	* set_capacity takes units of 512 bytes.
	412	*/
	413	set_capacity(md->disk, card->csd.capacity << (card->csd.read_blkbits - 9));
1da177e4	414	return md;
a6f6c96b RK	415
	416	err_putdisk:
	417	put_disk(md->disk);
	418	err_kfree:
	419	kfree(md);
	420	out:
	421	return ERR_PTR(ret);
1da177e4 LT	422	}
	423
	424	static int
	425	mmc_blk_set_blksize(struct mmc_blk_data md, struct mmc_card card)
	426	{
	427	struct mmc_command cmd;
	428	int err;
	429
	430	mmc_card_claim_host(card);
	431	cmd.opcode = MMC_SET_BLOCKLEN;
d2b18394	432	cmd.arg = 1 << md->block_bits;
e9225176	433	cmd.flags = MMC_RSP_R1 \| MMC_CMD_AC;
1da177e4 LT	434	err = mmc_wait_for_cmd(card->host, &cmd, 5);
	435	mmc_card_release_host(card);
	436
	437	if (err) {
	438	printk(KERN_ERR "%s: unable to set block size to %d: %d\n",
	439	md->disk->disk_name, cmd.arg, err);
	440	return -EINVAL;
	441	}
	442
	443	return 0;
	444	}
	445
	446	static int mmc_blk_probe(struct mmc_card *card)
	447	{
	448	struct mmc_blk_data *md;
	449	int err;
	450
912490db PO	451	/*
	452	* Check that the card supports the command class(es) we need.
	453	*/
	454	if (!(card->csd.cmdclass & CCC_BLOCK_READ))
1da177e4 LT	455	return -ENODEV;
1da177e4 LT	456
1da177e4 LT	457	md = mmc_blk_alloc(card);
	458	if (IS_ERR(md))
	459	return PTR_ERR(md);
	460
	461	err = mmc_blk_set_blksize(md, card);
	462	if (err)
	463	goto out;
	464
51828abc	465	printk(KERN_INFO "%s: %s %s %lluKiB %s\n",
1da177e4	466	md->disk->disk_name, mmc_card_id(card), mmc_card_name(card),
51828abc AM	467	(unsigned long long)(get_capacity(md->disk) >> 1),
51828abc AM	468	md->read_only ? "(ro)" : "");
1da177e4 LT	469
	470	mmc_set_drvdata(card, md);
	471	add_disk(md->disk);
	472	return 0;
	473
	474	out:
	475	mmc_blk_put(md);
	476
	477	return err;
	478	}
	479
	480	static void mmc_blk_remove(struct mmc_card *card)
	481	{
	482	struct mmc_blk_data *md = mmc_get_drvdata(card);
	483
	484	if (md) {
	485	int devidx;
	486
	487	del_gendisk(md->disk);
	488
	489	/*
	490	* I think this is needed.
	491	*/
	492	md->disk->queue = NULL;
	493
	494	devidx = md->disk->first_minor >> MMC_SHIFT;
	495	__clear_bit(devidx, dev_use);
	496
	497	mmc_blk_put(md);
	498	}
	499	mmc_set_drvdata(card, NULL);
	500	}
	501
	502	#ifdef CONFIG_PM
	503	static int mmc_blk_suspend(struct mmc_card *card, pm_message_t state)
	504	{
	505	struct mmc_blk_data *md = mmc_get_drvdata(card);
	506
	507	if (md) {
	508	mmc_queue_suspend(&md->queue);
	509	}
	510	return 0;
	511	}
	512
	513	static int mmc_blk_resume(struct mmc_card *card)
	514	{
	515	struct mmc_blk_data *md = mmc_get_drvdata(card);
	516
	517	if (md) {
	518	mmc_blk_set_blksize(md, card);
	519	mmc_queue_resume(&md->queue);
	520	}
	521	return 0;
	522	}
	523	#else
	524	#define mmc_blk_suspend NULL
	525	#define mmc_blk_resume NULL
	526	#endif
	527
	528	static struct mmc_driver mmc_driver = {
	529	.drv = {
	530	.name = "mmcblk",
	531	},
	532	.probe = mmc_blk_probe,
533	.remove = mmc_blk_remove,
534	.suspend = mmc_blk_suspend,
535	.resume = mmc_blk_resume,
536	};
537
538	static int __init mmc_blk_init(void)
539	{
540	int res = -ENOMEM;
541
542	res = register_blkdev(major, "mmc");
543	if (res < 0) {
544	printk(KERN_WARNING "Unable to get major %d for MMC media: %d\n",
545	major, res);
546	goto out;
547	}
548	if (major == 0)
549	major = res;
550
1da177e4 LT	551	return mmc_register_driver(&mmc_driver);
	552
	553	out:
	554	return res;
	555	}
	556
	557	static void __exit mmc_blk_exit(void)
	558	{
	559	mmc_unregister_driver(&mmc_driver);
1da177e4 LT	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");