/* * 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/mutex.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	3static 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 intmmc_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.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 | MMC_CMD_AC;		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",				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 intmmc_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_PMstatic 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#endifstatic 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");