/* * Block driver for media (i.e., flash cards) * * Copyright 2002 Hewlett-Packard Company * Copyright 2005-2008 Pierre Ossman * * Use consistent with the GNU GPL is permitted, * provided that this copyright notice is * preserved in its entirety in all copies and derived works. * * HEWLETT-PACKARD COMPANY MAKES NO WARRANTIES, EXPRESSED OR IMPLIED, * AS TO THE USEFULNESS OR CORRECTNESS OF THIS CODE OR ITS * FITNESS FOR ANY PARTICULAR PURPOSE. * * Many thanks to Alessandro Rubini and Jonathan Corbet! * * Author: Andrew Christian * 28 May 2002 */ #include <linux/moduleparam.h> #include <linux/module.h> #include <linux/init.h> #include <linux/kernel.h> #include <linux/fs.h> #include <linux/errno.h> #include <linux/hdreg.h> #include <linux/kdev_t.h> #include <linux/blkdev.h> #include <linux/mutex.h> #include <linux/scatterlist.h> #include <linux/string_helpers.h> #include <linux/mmc/card.h> #include <linux/mmc/host.h> #include <linux/mmc/mmc.h> #include <linux/mmc/sd.h> #include <asm/system.h> #include <asm/uaccess.h> #include "queue.h" /* * max 8 partitions per card */ #define MMC_SHIFT 3 #define MMC_NUM_MINORS (256 >> MMC_SHIFT) static DECLARE_BITMAP(dev_use, MMC_NUM_MINORS); /* * There is one mmc_blk_data per slot. */ struct mmc_blk_data { spinlock_t lock; struct gendisk *disk; struct mmc_queue queue; unsigned int usage; unsigned int read_only; }; static DEFINE_MUTEX(open_lock); static struct mmc_blk_data *mmc_blk_get(struct gendisk *disk) { struct mmc_blk_data *md; mutex_lock(&open_lock); md = disk->private_data; if (md && md->usage == 0) md = NULL; if (md) md->usage++; mutex_unlock(&open_lock); return md; } static void mmc_blk_put(struct mmc_blk_data *md) { mutex_lock(&open_lock); md->usage--; if (md->usage == 0) { int devidx = MINOR(disk_devt(md->disk)) >> MMC_SHIFT; __clear_bit(devidx, dev_use); put_disk(md->disk); kfree(md); } mutex_unlock(&open_lock); } static int mmc_blk_open(struct block_device *bdev, fmode_t mode) { struct mmc_blk_data *md = mmc_blk_get(bdev->bd_disk); int ret = -ENXIO; if (md) { if (md->usage == 2) check_disk_change(bdev); ret = 0; if ((mode & FMODE_WRITE) && md->read_only) { mmc_blk_put(md); ret = -EROFS; } } return ret; } static int mmc_blk_release(struct gendisk *disk, fmode_t mode) { struct mmc_blk_data *md = 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 u32 mmc_sd_num_wr_blocks(struct mmc_card *card) { int err; __be32 blocks; struct mmc_request mrq; struct mmc_command cmd; struct mmc_data data; unsigned int timeout_us; struct scatterlist sg; memset(&cmd, 0, sizeof(struct mmc_command)); cmd.opcode = MMC_APP_CMD; cmd.arg = card->rca << 16; cmd.flags = MMC_RSP_SPI_R1 | MMC_RSP_R1 | MMC_CMD_AC; err = mmc_wait_for_cmd(card->host, &cmd, 0); if (err) return (u32)-1; if (!mmc_host_is_spi(card->host) && !(cmd.resp[0] & R1_APP_CMD)) return (u32)-1; memset(&cmd, 0, sizeof(struct mmc_command)); cmd.opcode = SD_APP_SEND_NUM_WR_BLKS; cmd.arg = 0; cmd.flags = MMC_RSP_SPI_R1 | MMC_RSP_R1 | MMC_CMD_ADTC; memset(&data, 0, sizeof(struct mmc_data)); data.timeout_ns = card->csd.tacc_ns * 100; data.timeout_clks = card->csd.tacc_clks * 100; timeout_us = data.timeout_ns / 1000; timeout_us += data.timeout_clks * 1000 / (card->host->ios.clock / 1000); if (timeout_us > 100000) { data.timeout_ns = 100000000; data.timeout_clks = 0; } data.blksz = 4; data.blocks = 1; data.flags = MMC_DATA_READ; data.sg = &sg; data.sg_len = 1; memset(&mrq, 0, sizeof(struct mmc_request)); mrq.cmd = &cmd; mrq.data = &data; sg_init_one(&sg, &blocks, 4); mmc_wait_for_req(card->host, &mrq); if (cmd.error || data.error) return (u32)-1; return ntohl(blocks); } static u32 get_card_status(struct mmc_card *card, struct request *req) { struct mmc_command cmd; int err; memset(&cmd, 0, sizeof(struct mmc_command)); cmd.opcode = MMC_SEND_STATUS; if (!mmc_host_is_spi(card->host)) cmd.arg = card->rca << 16; cmd.flags = MMC_RSP_SPI_R2 | MMC_RSP_R1 | MMC_CMD_AC; err = mmc_wait_for_cmd(card->host, &cmd, 0); if (err) printk(KERN_ERR "%s: error %d sending status comand", req->rq_disk->disk_name, err); return cmd.resp[0]; } 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; struct mmc_blk_request brq; int ret = 1, disable_multi = 0; mmc_claim_host(card->host); do { struct mmc_command cmd; u32 readcmd, writecmd, status = 0; memset(&brq, 0, sizeof(struct mmc_blk_request)); brq.mrq.cmd = &brq.cmd; brq.mrq.data = &brq.data; brq.cmd.arg = req->sector; if (!mmc_card_blockaddr(card)) brq.cmd.arg <<= 9; brq.cmd.flags = MMC_RSP_SPI_R1 | MMC_RSP_R1 | MMC_CMD_ADTC; brq.data.blksz = 512; brq.stop.opcode = MMC_STOP_TRANSMISSION; brq.stop.arg = 0; brq.stop.flags = MMC_RSP_SPI_R1B | MMC_RSP_R1B | MMC_CMD_AC; brq.data.blocks = req->nr_sectors; /* * After a read error, we redo the request one sector at a time * in order to accurately determine which sectors can be read * successfully. */ if (disable_multi && brq.data.blocks > 1) brq.data.blocks = 1; if (brq.data.blocks > 1) { /* SPI multiblock writes terminate using a special * token, not a STOP_TRANSMISSION request. */ if (!mmc_host_is_spi(card->host) || rq_data_dir(req) == READ) brq.mrq.stop = &brq.stop; readcmd = MMC_READ_MULTIPLE_BLOCK; writecmd = MMC_WRITE_MULTIPLE_BLOCK; } else { brq.mrq.stop = NULL; readcmd = MMC_READ_SINGLE_BLOCK; writecmd = MMC_WRITE_BLOCK; } if (rq_data_dir(req) == READ) { brq.cmd.opcode = readcmd; brq.data.flags |= MMC_DATA_READ; } else { brq.cmd.opcode = writecmd; brq.data.flags |= MMC_DATA_WRITE; } mmc_set_data_timeout(&brq.data, card); brq.data.sg = mq->sg; brq.data.sg_len = mmc_queue_map_sg(mq); /* * Adjust the sg list so it is the same size as the * request. */ if (brq.data.blocks != req->nr_sectors) { int i, data_size = brq.data.blocks << 9; struct scatterlist *sg; for_each_sg(brq.data.sg, sg, brq.data.sg_len, i) { data_size -= sg->length; if (data_size <= 0) { sg->length += data_size; i++; break; } } brq.data.sg_len = i; } mmc_queue_bounce_pre(mq); mmc_wait_for_req(card->host, &brq.mrq); mmc_queue_bounce_post(mq); /* * Check for errors here, but don't jump to cmd_err * until later as we need to wait for the card to leave * programming mode even when things go wrong. */ if (brq.cmd.error || brq.data.error || brq.stop.error) { if (brq.data.blocks > 1 && rq_data_dir(req) == READ) { /* Redo read one sector at a time */ printk(KERN_WARNING "%s: retrying using single " "block read\n", req->rq_disk->disk_name); disable_multi = 1; continue; } status = get_card_status(card, req); } if (brq.cmd.error) { printk(KERN_ERR "%s: error %d sending read/write " "command, response %#x, card status %#x\n", req->rq_disk->disk_name, brq.cmd.error, brq.cmd.resp[0], status); } if (brq.data.error) { if (brq.data.error == -ETIMEDOUT && brq.mrq.stop) /* 'Stop' response contains card status */ status = brq.mrq.stop->resp[0]; printk(KERN_ERR "%s: error %d transferring data," " sector %u, nr %u, card status %#x\n", req->rq_disk->disk_name, brq.data.error, (unsigned)req->sector, (unsigned)req->nr_sectors, status); } if (brq.stop.error) { printk(KERN_ERR "%s: error %d sending stop command, " "response %#x, card status %#x\n", req->rq_disk->disk_name, brq.stop.error, brq.stop.resp[0], status); } if (!mmc_host_is_spi(card->host) && rq_data_dir(req) != READ) { do { int err; cmd.opcode = MMC_SEND_STATUS; cmd.arg = card->rca << 16; cmd.flags = MMC_RSP_R1 | MMC_CMD_AC; err = mmc_wait_for_cmd(card->host, &cmd, 5); if (err) { printk(KERN_ERR "%s: error %d requesting status\n", req->rq_disk->disk_name, err); goto cmd_err; } /* * Some cards mishandle the status bits, * so make sure to check both the busy * indication and the card state. */ } while (!(cmd.resp[0] & R1_READY_FOR_DATA) || (R1_CURRENT_STATE(cmd.resp[0]) == 7)); #if 0 if (cmd.resp[0] & ~0x00000900) printk(KERN_ERR "%s: status = %08x\n", req->rq_disk->disk_name, cmd.resp[0]); if (mmc_decode_status(cmd.resp)) goto cmd_err; #endif } if (brq.cmd.error || brq.stop.error || brq.data.error) { if (rq_data_dir(req) == READ) { /* * After an error, we redo I/O one sector at a * time, so we only reach here after trying to * read a single sector. */ spin_lock_irq(&md->lock); ret = __blk_end_request(req, -EIO, brq.data.blksz); spin_unlock_irq(&md->lock); continue; } goto cmd_err; } /* * A block was successfully transferred. */ spin_lock_irq(&md->lock); ret = __blk_end_request(req, 0, brq.data.bytes_xfered); spin_unlock_irq(&md->lock); } while (ret); mmc_release_host(card->host); return 1; cmd_err: /* * If this is an SD card and we're writing, we can first * mark the known good sectors as ok. * * If the card is not SD, we can still ok written sectors * as reported by the controller (which might be less than * the real number of written sectors, but never more). */ if (mmc_card_sd(card)) { u32 blocks; blocks = mmc_sd_num_wr_blocks(card); if (blocks != (u32)-1) { spin_lock_irq(&md->lock); ret = __blk_end_request(req, 0, blocks << 9); spin_unlock_irq(&md->lock); } } else { spin_lock_irq(&md->lock); ret = __blk_end_request(req, 0, brq.data.bytes_xfered); spin_unlock_irq(&md->lock); } mmc_release_host(card->host); spin_lock_irq(&md->lock); while (ret) ret = __blk_end_request(req, -EIO, blk_rq_cur_bytes(req)); spin_unlock_irq(&md->lock); return 0; } static 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 = kzalloc(sizeof(struct mmc_blk_data), GFP_KERNEL); if (!md) { ret = -ENOMEM; goto out; } /* * Set the read-only status based on the supported commands * and the write protect switch. */ md->read_only = mmc_blk_readonly(card); md->disk = alloc_disk(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.issue_fn = mmc_blk_issue_rq; md->queue.data = md; md->disk->major = MMC_BLOCK_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, 512); if (!mmc_card_sd(card) && mmc_card_blockaddr(card)) { /* * The EXT_CSD sector count is in number or 512 byte * sectors. */ set_capacity(md->disk, card->ext_csd.sectors); } else { /* * The CSD capacity field is in units of read_blkbits. * set_capacity takes units of 512 bytes. */ set_capacity(md->disk, card->csd.capacity << (card->csd.read_blkbits - 9)); } return md; err_putdisk: put_disk(md->disk); err_kfree: kfree(md); out: return ERR_PTR(ret); } static int mmc_blk_set_blksize(struct mmc_blk_data *md, struct mmc_card *card) { struct mmc_command cmd; int err; /* Block-addressed cards ignore MMC_SET_BLOCKLEN. */ if (mmc_card_blockaddr(card)) return 0; mmc_claim_host(card->host); cmd.opcode = MMC_SET_BLOCKLEN; cmd.arg = 512; cmd.flags = MMC_RSP_SPI_R1 | MMC_RSP_R1 | MMC_CMD_AC; err = mmc_wait_for_cmd(card->host, &cmd, 5); mmc_release_host(card->host); 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; char cap_str[10]; /* * Check that the card supports the command class(es) we need. */ if (!(card->csd.cmdclass & CCC_BLOCK_READ)) return -ENODEV; md = mmc_blk_alloc(card); if (IS_ERR(md)) return PTR_ERR(md); err = mmc_blk_set_blksize(md, card); if (err) goto out; string_get_size((u64)get_capacity(md->disk) << 9, STRING_UNITS_2, cap_str, sizeof(cap_str)); printk(KERN_INFO "%s: %s %s %s %s\n", md->disk->disk_name, mmc_card_id(card), mmc_card_name(card), cap_str, md->read_only ? "(ro)" : ""); mmc_set_drvdata(card, md); 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) { /* Stop new requests from getting into the queue */ del_gendisk(md->disk); /* Then flush out any already in there */ mmc_cleanup_queue(&md->queue); mmc_blk_put(md); } mmc_set_drvdata(card, NULL); } #ifdef CONFIG_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; res = register_blkdev(MMC_BLOCK_MAJOR, "mmc"); if (res) goto out; res = mmc_register_driver(&mmc_driver); if (res) goto out2; return 0; out2: unregister_blkdev(MMC_BLOCK_MAJOR, "mmc"); out: return res; } static void __exit mmc_blk_exit(void) { mmc_unregister_driver(&mmc_driver); unregister_blkdev(MMC_BLOCK_MAJOR, "mmc"); } module_init(mmc_blk_init); module_exit(mmc_blk_exit); MODULE_LICENSE("GPL"); MODULE_DESCRIPTION("Multimedia Card (MMC) block device driver");