git.oblomov.eu Git - linux-2.6/blob - drivers/mmc/card/block.c

   1 /*
   2  * Block driver for media (i.e., flash cards)
   3  *
   4  * Copyright 2002 Hewlett-Packard Company
   5  * Copyright 2005-2008 Pierre Ossman
   6  *
   7  * Use consistent with the GNU GPL is permitted,
   8  * provided that this copyright notice is
   9  * preserved in its entirety in all copies and derived works.
  10  *
  11  * HEWLETT-PACKARD COMPANY MAKES NO WARRANTIES, EXPRESSED OR IMPLIED,
  12  * AS TO THE USEFULNESS OR CORRECTNESS OF THIS CODE OR ITS
  13  * FITNESS FOR ANY PARTICULAR PURPOSE.
  14  *
  15  * Many thanks to Alessandro Rubini and Jonathan Corbet!
  16  *
  17  * Author:  Andrew Christian
  18  *          28 May 2002
  19  */
  20 #include <linux/moduleparam.h>
  21 #include <linux/module.h>
  22 #include <linux/init.h>
  23
  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/mutex.h>
  31 #include <linux/scatterlist.h>
  32 #include <linux/string_helpers.h>
  33
  34 #include <linux/mmc/card.h>
  35 #include <linux/mmc/host.h>
  36 #include <linux/mmc/mmc.h>
  37 #include <linux/mmc/sd.h>
  38
  39 #include <asm/system.h>
  40 #include <asm/uaccess.h>
  41
  42 #include "queue.h"
  43
  44 /*
  45  * max 8 partitions per card
  46  */
  47 #define MMC_SHIFT       3
  48 #define MMC_NUM_MINORS  (256 >> MMC_SHIFT)
  49
  50 static DECLARE_BITMAP(dev_use, MMC_NUM_MINORS);
  51
  52 /*
  53  * There is one mmc_blk_data per slot.
  54  */
  55 struct mmc_blk_data {
  56         spinlock_t      lock;
  57         struct gendisk  *disk;
  58         struct mmc_queue queue;
  59
  60         unsigned int    usage;
  61         unsigned int    read_only;
  62 };
  63
  64 static DEFINE_MUTEX(open_lock);
  65
  66 static struct mmc_blk_data *mmc_blk_get(struct gendisk *disk)
  67 {
  68         struct mmc_blk_data *md;
  69
  70         mutex_lock(&open_lock);
  71         md = disk->private_data;
  72         if (md && md->usage == 0)
  73                 md = NULL;
  74         if (md)
  75                 md->usage++;
  76         mutex_unlock(&open_lock);
  77
  78         return md;
  79 }
  80
  81 static void mmc_blk_put(struct mmc_blk_data *md)
  82 {
  83         mutex_lock(&open_lock);
  84         md->usage--;
  85         if (md->usage == 0) {
  86                 int devidx = MINOR(disk_devt(md->disk)) >> MMC_SHIFT;
  87                 __clear_bit(devidx, dev_use);
  88
  89                 put_disk(md->disk);
  90                 kfree(md);
  91         }
  92         mutex_unlock(&open_lock);
  93 }
  94
  95 static int mmc_blk_open(struct block_device *bdev, fmode_t mode)
  96 {
  97         struct mmc_blk_data *md = mmc_blk_get(bdev->bd_disk);
  98         int ret = -ENXIO;
  99
 100         if (md) {
 101                 if (md->usage == 2)
 102                         check_disk_change(bdev);
 103                 ret = 0;
 104
 105                 if ((mode & FMODE_WRITE) && md->read_only) {
 106                         mmc_blk_put(md);
 107                         ret = -EROFS;
 108                 }
 109         }
 110
 111         return ret;
 112 }
 113
 114 static int mmc_blk_release(struct gendisk *disk, fmode_t mode)
 115 {
 116         struct mmc_blk_data *md = disk->private_data;
 117
 118         mmc_blk_put(md);
 119         return 0;
 120 }
 121
 122 static int
 123 mmc_blk_getgeo(struct block_device *bdev, struct hd_geometry *geo)
 124 {
 125         geo->cylinders = get_capacity(bdev->bd_disk) / (4 * 16);
 126         geo->heads = 4;
 127         geo->sectors = 16;
 128         return 0;
 129 }
 130
 131 static struct block_device_operations mmc_bdops = {
 132         .open                   = mmc_blk_open,
 133         .release                = mmc_blk_release,
 134         .getgeo                 = mmc_blk_getgeo,
 135         .owner                  = THIS_MODULE,
 136 };
 137
 138 struct mmc_blk_request {
 139         struct mmc_request      mrq;
 140         struct mmc_command      cmd;
 141         struct mmc_command      stop;
 142         struct mmc_data         data;
 143 };
 144
 145 static u32 mmc_sd_num_wr_blocks(struct mmc_card *card)
 146 {
 147         int err;
 148         __be32 blocks;
 149
 150         struct mmc_request mrq;
 151         struct mmc_command cmd;
 152         struct mmc_data data;
 153         unsigned int timeout_us;
 154
 155         struct scatterlist sg;
 156
 157         memset(&cmd, 0, sizeof(struct mmc_command));
 158
 159         cmd.opcode = MMC_APP_CMD;
 160         cmd.arg = card->rca << 16;
 161         cmd.flags = MMC_RSP_SPI_R1 | MMC_RSP_R1 | MMC_CMD_AC;
 162
 163         err = mmc_wait_for_cmd(card->host, &cmd, 0);
 164         if (err)
 165                 return (u32)-1;
 166         if (!mmc_host_is_spi(card->host) && !(cmd.resp[0] & R1_APP_CMD))
 167                 return (u32)-1;
 168
 169         memset(&cmd, 0, sizeof(struct mmc_command));
 170
 171         cmd.opcode = SD_APP_SEND_NUM_WR_BLKS;
 172         cmd.arg = 0;
 173         cmd.flags = MMC_RSP_SPI_R1 | MMC_RSP_R1 | MMC_CMD_ADTC;
 174
 175         memset(&data, 0, sizeof(struct mmc_data));
 176
 177         data.timeout_ns = card->csd.tacc_ns * 100;
 178         data.timeout_clks = card->csd.tacc_clks * 100;
 179
 180         timeout_us = data.timeout_ns / 1000;
 181         timeout_us += data.timeout_clks * 1000 /
 182                 (card->host->ios.clock / 1000);
 183
 184         if (timeout_us > 100000) {
 185                 data.timeout_ns = 100000000;
 186                 data.timeout_clks = 0;
 187         }
 188
 189         data.blksz = 4;
 190         data.blocks = 1;
 191         data.flags = MMC_DATA_READ;
 192         data.sg = &sg;
 193         data.sg_len = 1;
 194
 195         memset(&mrq, 0, sizeof(struct mmc_request));
 196
 197         mrq.cmd = &cmd;
 198         mrq.data = &data;
 199
 200         sg_init_one(&sg, &blocks, 4);
 201
 202         mmc_wait_for_req(card->host, &mrq);
 203
 204         if (cmd.error || data.error)
 205                 return (u32)-1;
 206
 207         return ntohl(blocks);
 208 }
 209
 210 static u32 get_card_status(struct mmc_card *card, struct request *req)
 211 {
 212         struct mmc_command cmd;
 213         int err;
 214
 215         memset(&cmd, 0, sizeof(struct mmc_command));
 216         cmd.opcode = MMC_SEND_STATUS;
 217         if (!mmc_host_is_spi(card->host))
 218                 cmd.arg = card->rca << 16;
 219         cmd.flags = MMC_RSP_SPI_R2 | MMC_RSP_R1 | MMC_CMD_AC;
 220         err = mmc_wait_for_cmd(card->host, &cmd, 0);
 221         if (err)
 222                 printk(KERN_ERR "%s: error %d sending status comand",
 223                        req->rq_disk->disk_name, err);
 224         return cmd.resp[0];
 225 }
 226
 227 static int mmc_blk_issue_rq(struct mmc_queue *mq, struct request *req)
 228 {
 229         struct mmc_blk_data *md = mq->data;
 230         struct mmc_card *card = md->queue.card;
 231         struct mmc_blk_request brq;
 232         int ret = 1, disable_multi = 0;
 233
 234         mmc_claim_host(card->host);
 235
 236         do {
 237                 struct mmc_command cmd;
 238                 u32 readcmd, writecmd, status = 0;
 239
 240                 memset(&brq, 0, sizeof(struct mmc_blk_request));
 241                 brq.mrq.cmd = &brq.cmd;
 242                 brq.mrq.data = &brq.data;
 243
 244                 brq.cmd.arg = req->sector;
 245                 if (!mmc_card_blockaddr(card))
 246                         brq.cmd.arg <<= 9;
 247                 brq.cmd.flags = MMC_RSP_SPI_R1 | MMC_RSP_R1 | MMC_CMD_ADTC;
 248                 brq.data.blksz = 512;
 249                 brq.stop.opcode = MMC_STOP_TRANSMISSION;
 250                 brq.stop.arg = 0;
 251                 brq.stop.flags = MMC_RSP_SPI_R1B | MMC_RSP_R1B | MMC_CMD_AC;
 252                 brq.data.blocks = req->nr_sectors;
 253
 254                 /*
 255                  * After a read error, we redo the request one sector at a time
 256                  * in order to accurately determine which sectors can be read
 257                  * successfully.
 258                  */
 259                 if (disable_multi && brq.data.blocks > 1)
 260                         brq.data.blocks = 1;
 261
 262                 if (brq.data.blocks > 1) {
 263                         /* SPI multiblock writes terminate using a special
 264                          * token, not a STOP_TRANSMISSION request.
 265                          */
 266                         if (!mmc_host_is_spi(card->host)
 267                                         || rq_data_dir(req) == READ)
 268                                 brq.mrq.stop = &brq.stop;
 269                         readcmd = MMC_READ_MULTIPLE_BLOCK;
 270                         writecmd = MMC_WRITE_MULTIPLE_BLOCK;
 271                 } else {
 272                         brq.mrq.stop = NULL;
 273                         readcmd = MMC_READ_SINGLE_BLOCK;
 274                         writecmd = MMC_WRITE_BLOCK;
 275                 }
 276
 277                 if (rq_data_dir(req) == READ) {
 278                         brq.cmd.opcode = readcmd;
 279                         brq.data.flags |= MMC_DATA_READ;
 280                 } else {
 281                         brq.cmd.opcode = writecmd;
 282                         brq.data.flags |= MMC_DATA_WRITE;
 283                 }
 284
 285                 mmc_set_data_timeout(&brq.data, card);
 286
 287                 brq.data.sg = mq->sg;
 288                 brq.data.sg_len = mmc_queue_map_sg(mq);
 289
 290                 /*
 291                  * Adjust the sg list so it is the same size as the
 292                  * request.
 293                  */
 294                 if (brq.data.blocks != req->nr_sectors) {
 295                         int i, data_size = brq.data.blocks << 9;
 296                         struct scatterlist *sg;
 297
 298                         for_each_sg(brq.data.sg, sg, brq.data.sg_len, i) {
 299                                 data_size -= sg->length;
 300                                 if (data_size <= 0) {
 301                                         sg->length += data_size;
 302                                         i++;
 303                                         break;
 304                                 }
 305                         }
 306                         brq.data.sg_len = i;
 307                 }
 308
 309                 mmc_queue_bounce_pre(mq);
 310
 311                 mmc_wait_for_req(card->host, &brq.mrq);
 312
 313                 mmc_queue_bounce_post(mq);
 314
 315                 /*
 316                  * Check for errors here, but don't jump to cmd_err
 317                  * until later as we need to wait for the card to leave
 318                  * programming mode even when things go wrong.
 319                  */
 320                 if (brq.cmd.error || brq.data.error || brq.stop.error) {
 321                         if (brq.data.blocks > 1 && rq_data_dir(req) == READ) {
 322                                 /* Redo read one sector at a time */
 323                                 printk(KERN_WARNING "%s: retrying using single "
 324                                        "block read\n", req->rq_disk->disk_name);
 325                                 disable_multi = 1;
 326                                 continue;
 327                         }
 328                         status = get_card_status(card, req);
 329                 }
 330
 331                 if (brq.cmd.error) {
 332                         printk(KERN_ERR "%s: error %d sending read/write "
 333                                "command, response %#x, card status %#x\n",
 334                                req->rq_disk->disk_name, brq.cmd.error,
 335                                brq.cmd.resp[0], status);
 336                 }
 337
 338                 if (brq.data.error) {
 339                         if (brq.data.error == -ETIMEDOUT && brq.mrq.stop)
 340                                 /* 'Stop' response contains card status */
 341                                 status = brq.mrq.stop->resp[0];
 342                         printk(KERN_ERR "%s: error %d transferring data,"
 343                                " sector %u, nr %u, card status %#x\n",
 344                                req->rq_disk->disk_name, brq.data.error,
 345                                (unsigned)req->sector,
 346                                (unsigned)req->nr_sectors, status);
 347                 }
 348
 349                 if (brq.stop.error) {
 350                         printk(KERN_ERR "%s: error %d sending stop command, "
 351                                "response %#x, card status %#x\n",
 352                                req->rq_disk->disk_name, brq.stop.error,
 353                                brq.stop.resp[0], status);
 354                 }
 355
 356                 if (!mmc_host_is_spi(card->host) && rq_data_dir(req) != READ) {
 357                         do {
 358                                 int err;
 359
 360                                 cmd.opcode = MMC_SEND_STATUS;
 361                                 cmd.arg = card->rca << 16;
 362                                 cmd.flags = MMC_RSP_R1 | MMC_CMD_AC;
 363                                 err = mmc_wait_for_cmd(card->host, &cmd, 5);
 364                                 if (err) {
 365                                         printk(KERN_ERR "%s: error %d requesting status\n",
 366                                                req->rq_disk->disk_name, err);
 367                                         goto cmd_err;
 368                                 }
 369                                 /*
 370                                  * Some cards mishandle the status bits,
 371                                  * so make sure to check both the busy
 372                                  * indication and the card state.
 373                                  */
 374                         } while (!(cmd.resp[0] & R1_READY_FOR_DATA) ||
 375                                 (R1_CURRENT_STATE(cmd.resp[0]) == 7));
 376
 377 #if 0
 378                         if (cmd.resp[0] & ~0x00000900)
 379                                 printk(KERN_ERR "%s: status = %08x\n",
 380                                        req->rq_disk->disk_name, cmd.resp[0]);
 381                         if (mmc_decode_status(cmd.resp))
 382                                 goto cmd_err;
 383 #endif
 384                 }
 385
 386                 if (brq.cmd.error || brq.stop.error || brq.data.error) {
 387                         if (rq_data_dir(req) == READ) {
 388                                 /*
 389                                  * After an error, we redo I/O one sector at a
 390                                  * time, so we only reach here after trying to
 391                                  * read a single sector.
 392                                  */
 393                                 spin_lock_irq(&md->lock);
 394                                 ret = __blk_end_request(req, -EIO, brq.data.blksz);
 395                                 spin_unlock_irq(&md->lock);
 396                                 continue;
 397                         }
 398                         goto cmd_err;
 399                 }
 400
 401                 /*
 402                  * A block was successfully transferred.
 403                  */
 404                 spin_lock_irq(&md->lock);
 405                 ret = __blk_end_request(req, 0, brq.data.bytes_xfered);
 406                 spin_unlock_irq(&md->lock);
 407         } while (ret);
 408
 409         mmc_release_host(card->host);
 410
 411         return 1;
 412
 413  cmd_err:
 414         /*
 415          * If this is an SD card and we're writing, we can first
 416          * mark the known good sectors as ok.
 417          *
 418          * If the card is not SD, we can still ok written sectors
 419          * as reported by the controller (which might be less than
 420          * the real number of written sectors, but never more).
 421          */
 422         if (mmc_card_sd(card)) {
 423                 u32 blocks;
 424
 425                 blocks = mmc_sd_num_wr_blocks(card);
 426                 if (blocks != (u32)-1) {
 427                         spin_lock_irq(&md->lock);
 428                         ret = __blk_end_request(req, 0, blocks << 9);
 429                         spin_unlock_irq(&md->lock);
 430                 }
 431         } else {
 432                 spin_lock_irq(&md->lock);
 433                 ret = __blk_end_request(req, 0, brq.data.bytes_xfered);
 434                 spin_unlock_irq(&md->lock);
 435         }
 436
 437         mmc_release_host(card->host);
 438
 439         spin_lock_irq(&md->lock);
 440         while (ret)
 441                 ret = __blk_end_request(req, -EIO, blk_rq_cur_bytes(req));
 442         spin_unlock_irq(&md->lock);
 443
 444         return 0;
 445 }
 446
 447
 448 static inline int mmc_blk_readonly(struct mmc_card *card)
 449 {
 450         return mmc_card_readonly(card) ||
 451                !(card->csd.cmdclass & CCC_BLOCK_WRITE);
 452 }
 453
 454 static struct mmc_blk_data *mmc_blk_alloc(struct mmc_card *card)
 455 {
 456         struct mmc_blk_data *md;
 457         int devidx, ret;
 458
 459         devidx = find_first_zero_bit(dev_use, MMC_NUM_MINORS);
 460         if (devidx >= MMC_NUM_MINORS)
 461                 return ERR_PTR(-ENOSPC);
 462         __set_bit(devidx, dev_use);
 463
 464         md = kzalloc(sizeof(struct mmc_blk_data), GFP_KERNEL);
 465         if (!md) {
 466                 ret = -ENOMEM;
 467                 goto out;
 468         }
 469
 470
 471         /*
 472          * Set the read-only status based on the supported commands
 473          * and the write protect switch.
 474          */
 475         md->read_only = mmc_blk_readonly(card);
 476
 477         md->disk = alloc_disk(1 << MMC_SHIFT);
 478         if (md->disk == NULL) {
 479                 ret = -ENOMEM;
 480                 goto err_kfree;
 481         }
 482
 483         spin_lock_init(&md->lock);
 484         md->usage = 1;
 485
 486         ret = mmc_init_queue(&md->queue, card, &md->lock);
 487         if (ret)
 488                 goto err_putdisk;
 489
 490         md->queue.issue_fn = mmc_blk_issue_rq;
 491         md->queue.data = md;
 492
 493         md->disk->major = MMC_BLOCK_MAJOR;
 494         md->disk->first_minor = devidx << MMC_SHIFT;
 495         md->disk->fops = &mmc_bdops;
 496         md->disk->private_data = md;
 497         md->disk->queue = md->queue.queue;
 498         md->disk->driverfs_dev = &card->dev;
 499
 500         /*
 501          * As discussed on lkml, GENHD_FL_REMOVABLE should:
 502          *
 503          * - be set for removable media with permanent block devices
 504          * - be unset for removable block devices with permanent media
 505          *
 506          * Since MMC block devices clearly fall under the second
 507          * case, we do not set GENHD_FL_REMOVABLE.  Userspace
 508          * should use the block device creation/destruction hotplug
 509          * messages to tell when the card is present.
 510          */
 511
 512         sprintf(md->disk->disk_name, "mmcblk%d", devidx);
 513
 514         blk_queue_hardsect_size(md->queue.queue, 512);
 515
 516         if (!mmc_card_sd(card) && mmc_card_blockaddr(card)) {
 517                 /*
 518                  * The EXT_CSD sector count is in number or 512 byte
 519                  * sectors.
 520                  */
 521                 set_capacity(md->disk, card->ext_csd.sectors);
 522         } else {
 523                 /*
 524                  * The CSD capacity field is in units of read_blkbits.
 525                  * set_capacity takes units of 512 bytes.
 526                  */
 527                 set_capacity(md->disk,
 528                         card->csd.capacity << (card->csd.read_blkbits - 9));
 529         }
 530         return md;
 531
 532  err_putdisk:
 533         put_disk(md->disk);
 534  err_kfree:
 535         kfree(md);
 536  out:
 537         return ERR_PTR(ret);
 538 }
 539
 540 static int
 541 mmc_blk_set_blksize(struct mmc_blk_data *md, struct mmc_card *card)
 542 {
 543         struct mmc_command cmd;
 544         int err;
 545
 546         /* Block-addressed cards ignore MMC_SET_BLOCKLEN. */
 547         if (mmc_card_blockaddr(card))
 548                 return 0;
 549
 550         mmc_claim_host(card->host);
 551         cmd.opcode = MMC_SET_BLOCKLEN;
 552         cmd.arg = 512;
 553         cmd.flags = MMC_RSP_SPI_R1 | MMC_RSP_R1 | MMC_CMD_AC;
 554         err = mmc_wait_for_cmd(card->host, &cmd, 5);
 555         mmc_release_host(card->host);
 556
 557         if (err) {
 558                 printk(KERN_ERR "%s: unable to set block size to %d: %d\n",
 559                         md->disk->disk_name, cmd.arg, err);
 560                 return -EINVAL;
 561         }
 562
 563         return 0;
 564 }
 565
 566 static int mmc_blk_probe(struct mmc_card *card)
 567 {
 568         struct mmc_blk_data *md;
 569         int err;
 570
 571         char cap_str[10];
 572
 573         /*
 574          * Check that the card supports the command class(es) we need.
 575          */
 576         if (!(card->csd.cmdclass & CCC_BLOCK_READ))
 577                 return -ENODEV;
 578
 579         md = mmc_blk_alloc(card);
 580         if (IS_ERR(md))
 581                 return PTR_ERR(md);
 582
 583         err = mmc_blk_set_blksize(md, card);
 584         if (err)
 585                 goto out;
 586
 587         string_get_size((u64)get_capacity(md->disk) << 9, STRING_UNITS_2,
 588                         cap_str, sizeof(cap_str));
 589         printk(KERN_INFO "%s: %s %s %s %s\n",
 590                 md->disk->disk_name, mmc_card_id(card), mmc_card_name(card),
 591                 cap_str, md->read_only ? "(ro)" : "");
 592
 593         mmc_set_drvdata(card, md);
 594         add_disk(md->disk);
 595         return 0;
 596
 597  out:
 598         mmc_blk_put(md);
 599
 600         return err;
 601 }
 602
 603 static void mmc_blk_remove(struct mmc_card *card)
 604 {
 605         struct mmc_blk_data *md = mmc_get_drvdata(card);
 606
 607         if (md) {
 608                 /* Stop new requests from getting into the queue */
 609                 del_gendisk(md->disk);
 610
 611                 /* Then flush out any already in there */
 612                 mmc_cleanup_queue(&md->queue);
 613
 614                 mmc_blk_put(md);
 615         }
 616         mmc_set_drvdata(card, NULL);
 617 }
 618
 619 #ifdef CONFIG_PM
 620 static int mmc_blk_suspend(struct mmc_card *card, pm_message_t state)
 621 {
 622         struct mmc_blk_data *md = mmc_get_drvdata(card);
 623
 624         if (md) {
 625                 mmc_queue_suspend(&md->queue);
 626         }
 627         return 0;
 628 }
 629
 630 static int mmc_blk_resume(struct mmc_card *card)
 631 {
 632         struct mmc_blk_data *md = mmc_get_drvdata(card);
 633
 634         if (md) {
 635                 mmc_blk_set_blksize(md, card);
 636                 mmc_queue_resume(&md->queue);
 637         }
 638         return 0;
 639 }
 640 #else
 641 #define mmc_blk_suspend NULL
 642 #define mmc_blk_resume  NULL
 643 #endif
 644
 645 static struct mmc_driver mmc_driver = {
 646         .drv            = {
 647                 .name   = "mmcblk",
 648         },
 649         .probe          = mmc_blk_probe,
 650         .remove         = mmc_blk_remove,
 651         .suspend        = mmc_blk_suspend,
 652         .resume         = mmc_blk_resume,
 653 };
 654
 655 static int __init mmc_blk_init(void)
 656 {
 657         int res;
 658
 659         res = register_blkdev(MMC_BLOCK_MAJOR, "mmc");
 660         if (res)
 661                 goto out;
 662
 663         res = mmc_register_driver(&mmc_driver);
 664         if (res)
 665                 goto out2;
 666
 667         return 0;
 668  out2:
 669         unregister_blkdev(MMC_BLOCK_MAJOR, "mmc");
 670  out:
 671         return res;
 672 }
 673
 674 static void __exit mmc_blk_exit(void)
 675 {
 676         mmc_unregister_driver(&mmc_driver);
 677         unregister_blkdev(MMC_BLOCK_MAJOR, "mmc");
 678 }
 679
 680 module_init(mmc_blk_init);
 681 module_exit(mmc_blk_exit);
 682
 683 MODULE_LICENSE("GPL");
 684 MODULE_DESCRIPTION("Multimedia Card (MMC) block device driver");
 685