sys/dev/disk/mmcsd/mmcsd.c

   1 /*-
   2  * Copyright (c) 2006 Bernd Walter.  All rights reserved.
   3  * Copyright (c) 2006 M. Warner Losh.  All rights reserved.
   4  *
   5  * Redistribution and use in source and binary forms, with or without
   6  * modification, are permitted provided that the following conditions
   7  * are met:
   8  * 1. Redistributions of source code must retain the above copyright
   9  *    notice, this list of conditions and the following disclaimer.
  10  * 2. Redistributions in binary form must reproduce the above copyright
  11  *    notice, this list of conditions and the following disclaimer in the
  12  *    documentation and/or other materials provided with the distribution.
  13  *
  14  * THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR
  15  * IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES
  16  * OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED.
  17  * IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT,
  18  * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT
  19  * NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
  20  * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
  21  * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
  22  * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF
  23  * THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
  24  *
  25  * Portions of this software may have been developed with reference to
  26  * the SD Simplified Specification.  The following disclaimer may apply:
  27  *
  28  * The following conditions apply to the release of the simplified
  29  * specification ("Simplified Specification") by the SD Card Association and
  30  * the SD Group. The Simplified Specification is a subset of the complete SD
  31  * Specification which is owned by the SD Card Association and the SD
  32  * Group. This Simplified Specification is provided on a non-confidential
  33  * basis subject to the disclaimers below. Any implementation of the
  34  * Simplified Specification may require a license from the SD Card
  35  * Association, SD Group, SD-3C LLC or other third parties.
  36  *
  37  * Disclaimers:
  38  *
  39  * The information contained in the Simplified Specification is presented only
  40  * as a standard specification for SD Cards and SD Host/Ancillary products and
  41  * is provided "AS-IS" without any representations or warranties of any
  42  * kind. No responsibility is assumed by the SD Group, SD-3C LLC or the SD
  43  * Card Association for any damages, any infringements of patents or other
  44  * right of the SD Group, SD-3C LLC, the SD Card Association or any third
  45  * parties, which may result from its use. No license is granted by
  46  * implication, estoppel or otherwise under any patent or other rights of the
  47  * SD Group, SD-3C LLC, the SD Card Association or any third party. Nothing
  48  * herein shall be construed as an obligation by the SD Group, the SD-3C LLC
  49  * or the SD Card Association to disclose or distribute any technical
  50  * information, know-how or other confidential information to any third party.
  51  *
  52  * $FreeBSD: src/sys/dev/mmc/mmcsd.c,v 1.20 2009/02/17 19:17:25 mav Exp $
  53  */
  54
  55 #include <sys/param.h>
  56 #include <sys/systm.h>
  57 #include <sys/buf.h>
  58 #include <sys/bus.h>
  59 #include <sys/conf.h>
  60 #include <sys/disk.h>
  61 #include <sys/device.h>
  62 #include <sys/devicestat.h>
  63 #include <sys/kernel.h>
  64 #include <sys/kthread.h>
  65 #include <sys/lock.h>
  66 #include <sys/malloc.h>
  67 #include <sys/module.h>
  68 #include <sys/spinlock.h>
  69
  70 #include <sys/buf2.h>
  71
  72 #include <bus/mmc/mmcvar.h>
  73 #include <bus/mmc/mmcreg.h>
  74
  75 #include "mmcbus_if.h"
  76
  77 struct mmcsd_softc {
  78         device_t dev;
  79         cdev_t dev_t;
  80         struct lock sc_lock;
  81         struct disk disk;
  82         struct devstat device_stats;
  83         struct thread *td;
  84         struct bio_queue_head bio_queue;
  85         daddr_t eblock, eend;   /* Range remaining after the last erase. */
  86         int running;
  87         int suspend;
  88 };
  89
  90 /* bus entry points */
  91 static int mmcsd_probe(device_t dev);
  92 static int mmcsd_attach(device_t dev);
  93 static int mmcsd_detach(device_t dev);
  94
  95 /* disk routines */
  96 static d_open_t mmcsd_open;
  97 static d_close_t mmcsd_close;
  98 static d_strategy_t mmcsd_strategy;
  99 static d_dump_t mmcsd_dump;
 100
 101 static void mmcsd_task(void *arg);
 102
 103 static const char *mmcsd_card_name(device_t dev);
 104 static int mmcsd_bus_bit_width(device_t dev);
 105
 106 #define MMCSD_LOCK(_sc)         lockmgr(&(_sc)->sc_lock, LK_EXCLUSIVE)
 107 #define MMCSD_UNLOCK(_sc)       lockmgr(&(_sc)->sc_lock, LK_RELEASE)
 108 #define MMCSD_LOCK_INIT(_sc)    lockinit(&(_sc)->sc_lock, "mmcsd", 0, LK_CANRECURSE)
 109 #define MMCSD_LOCK_DESTROY(_sc) lockuninit(&(_sc)->sc_lock);
 110 #define MMCSD_ASSERT_LOCKED(_sc) KKASSERT(lockstatus(&(_sc)->sc_lock, curthread) != 0);
 111 #define MMCSD_ASSERT_UNLOCKED(_sc) KKASSERT(lockstatus(&(_sc)->sc_lock, curthread) == 0);
 112
 113 static struct dev_ops mmcsd_ops = {
 114         { "mmcsd", 0, D_DISK | D_MPSAFE },
 115         .d_open = mmcsd_open,
 116         .d_close = mmcsd_close,
 117         .d_strategy = mmcsd_strategy,
 118         .d_dump = mmcsd_dump,
 119 };
 120
 121 static int
 122 mmcsd_probe(device_t dev)
 123 {
 124
 125         device_quiet(dev);
 126         device_set_desc(dev, "MMC/SD Memory Card");
 127         return (0);
 128 }
 129
 130 static int
 131 mmcsd_attach(device_t dev)
 132 {
 133         struct mmcsd_softc *sc;
 134         struct disk_info info;
 135         cdev_t dsk;
 136         intmax_t mb;
 137         char unit;
 138         int sector_size;
 139
 140         sc = device_get_softc(dev);
 141         sc->dev = dev;
 142         MMCSD_LOCK_INIT(sc);
 143
 144         sector_size = mmc_get_sector_size(dev);
 145         devstat_add_entry(&sc->device_stats, "mmcsd", device_get_unit(dev),
 146             sector_size, DEVSTAT_NO_ORDERED_TAGS,
 147             DEVSTAT_TYPE_DIRECT | DEVSTAT_TYPE_IF_OTHER,
 148             DEVSTAT_PRIORITY_DISK);
 149
 150         bioq_init(&sc->bio_queue);
 151
 152         sc->running = 1;
 153         sc->suspend = 0;
 154         sc->eblock = sc->eend = 0;
 155         kthread_create(mmcsd_task, sc, &sc->td, "mmc/sd card task");
 156
 157         /*
 158          * Probe capacity
 159          */
 160         bzero(&info, sizeof(info));
 161         info.d_media_blksize = sector_size;
 162         info.d_media_blocks = mmc_get_media_size(dev);
 163         info.d_secpertrack = 1024;
 164         info.d_nheads = 1;
 165         info.d_secpercyl = info.d_secpertrack * info.d_nheads;
 166         info.d_ncylinders =  (u_int)(info.d_media_blocks / info.d_secpercyl);
 167
 168         /*
 169          * Display in most natural units.  There's no cards < 1MB.
 170          * The SD standard goes to 2GiB, but the data format supports
 171          * up to 4GiB and some card makers push it up to this limit.
 172          * The SDHC standard only goes to 32GiB (the data format in
 173          * SDHC is good to 2TiB however, which isn't too ugly at
 174          * 2048GiBm, so we note it in passing here and don't add the
 175          * code to print TiB).
 176          *
 177          * 1MiB == 1 << 20
 178          */
 179         mb = (info.d_media_blksize * info.d_media_blocks) >> 20;
 180         unit = 'M';
 181         if (mb >= 10240) {              /* 1GiB = 1024 MiB */
 182                 unit = 'G';
 183                 mb /= 1024;
 184         }
 185
 186         device_printf(dev, "%ju%cB <%s Memory Card>%s at %s %dMHz/%dbit\n",
 187             mb, unit, mmcsd_card_name(dev),
 188             mmc_get_read_only(dev) ? " (read-only)" : "",
 189             device_get_nameunit(device_get_parent(dev)),
 190             mmc_get_tran_speed(dev) / 1000000, mmcsd_bus_bit_width(dev));
 191
 192         /*
 193          * SC is fully initialized, we can attach the drive now.  The
 194          * instant we do the kernel will start probing it.
 195          */
 196         dsk = disk_create(device_get_unit(dev), &sc->disk, &mmcsd_ops);
 197         dsk->si_drv1 = sc;
 198         sc->dev_t = dsk;
 199
 200         /* Maximum defined SD card AU size. */
 201         dsk->si_iosize_max = 4*1024*1024;
 202
 203         disk_setdiskinfo(&sc->disk, &info);
 204
 205         return (0);
 206 }
 207
 208 static int
 209 mmcsd_detach(device_t dev)
 210 {
 211         struct mmcsd_softc *sc = device_get_softc(dev);
 212         struct buf *q_bp;
 213         struct bio *q_bio;
 214
 215         MMCSD_LOCK(sc);
 216         sc->suspend = 0;
 217         if (sc->running > 0) {
 218                 /* kill thread */
 219                 sc->running = 0;
 220                 wakeup(sc);
 221                 /* wait for thread to finish. */
 222                 while (sc->running != -1)
 223                         lksleep(sc, &sc->sc_lock, 0, "detach", 0);
 224         }
 225         MMCSD_UNLOCK(sc);
 226
 227         /*
 228          * Flush the request queue.
 229          *
 230          * XXX: Return all queued I/O with ENXIO. Is this correct?
 231          */
 232         while ((q_bio = bioq_takefirst(&sc->bio_queue)) != NULL) {
 233                 q_bp = q_bio->bio_buf;
 234                 q_bp->b_resid = q_bp->b_bcount;
 235                 q_bp->b_error = ENXIO;
 236                 q_bp->b_flags |= B_ERROR;
 237                 biodone(q_bio);
 238         }
 239
 240         /* kill disk */
 241         disk_destroy(&sc->disk);
 242         devstat_remove_entry(&sc->device_stats);
 243
 244         MMCSD_LOCK_DESTROY(sc);
 245
 246         return (0);
 247 }
 248
 249 static int
 250 mmcsd_suspend(device_t dev)
 251 {
 252         struct mmcsd_softc *sc = device_get_softc(dev);
 253
 254         MMCSD_LOCK(sc);
 255         sc->suspend = 1;
 256         if (sc->running > 0) {
 257                 /* kill thread */
 258                 sc->running = 0;
 259                 wakeup(sc);
 260                 /* wait for thread to finish. */
 261                 while (sc->running != -1)
 262                         lksleep(sc, &sc->sc_lock, 0, "detach", 0);
 263         }
 264         MMCSD_UNLOCK(sc);
 265         return (0);
 266 }
 267
 268 static int
 269 mmcsd_resume(device_t dev)
 270 {
 271         struct mmcsd_softc *sc = device_get_softc(dev);
 272
 273         MMCSD_LOCK(sc);
 274         sc->suspend = 0;
 275         if (sc->running <= 0) {
 276                 sc->running = 1;
 277                 MMCSD_UNLOCK(sc);
 278                 kthread_create(mmcsd_task, sc, &sc->td, "mmc/sd card task");
 279         } else
 280                 MMCSD_UNLOCK(sc);
 281         return (0);
 282 }
 283
 284 static int
 285 mmcsd_open(struct dev_open_args *ap __unused)
 286 {
 287         return (0);
 288 }
 289
 290 static int
 291 mmcsd_close(struct dev_close_args *ap __unused)
 292 {
 293         return (0);
 294 }
 295
 296 static int
 297 mmcsd_strategy(struct dev_strategy_args *ap)
 298 {
 299         struct mmcsd_softc *sc;
 300         struct bio *bio = ap->a_bio;
 301         struct buf *bp = bio->bio_buf;
 302
 303         sc = (struct mmcsd_softc *)ap->a_head.a_dev->si_drv1;
 304         MMCSD_LOCK(sc);
 305         if (sc->running > 0 || sc->suspend > 0) {
 306                 bioqdisksort(&sc->bio_queue, bio);
 307                 MMCSD_UNLOCK(sc);
 308                 wakeup(sc);
 309         } else {
 310                 MMCSD_UNLOCK(sc);
 311                 bp->b_error = ENXIO;
 312                 bp->b_flags |= B_ERROR;
 313                 bp->b_resid = bp->b_bcount;
 314                 biodone(bio);
 315         }
 316         return (0);
 317 }
 318
 319 static daddr_t
 320 mmcsd_rw(struct mmcsd_softc *sc, struct bio *bio)
 321 {
 322         daddr_t block, end;
 323         struct mmc_command cmd;
 324         struct mmc_command stop;
 325         struct mmc_request req;
 326         struct mmc_data data;
 327         device_t dev = sc->dev;
 328         int sz = sc->disk.d_info.d_media_blksize;
 329         struct buf *bp = bio->bio_buf;
 330
 331         block = bio->bio_offset / sz;
 332         end = block + (bp->b_bcount / sz);
 333         while (block < end) {
 334                 char *vaddr = bp->b_data +
 335                     (block - (bio->bio_offset / sz)) * sz;
 336                 int numblocks = min(end - block, mmc_get_max_data(dev));
 337                 memset(&req, 0, sizeof(req));
 338                 memset(&cmd, 0, sizeof(cmd));
 339                 memset(&stop, 0, sizeof(stop));
 340                 req.cmd = &cmd;
 341                 cmd.data = &data;
 342                 if (bp->b_cmd == BUF_CMD_READ) {
 343                         if (numblocks > 1)
 344                                 cmd.opcode = MMC_READ_MULTIPLE_BLOCK;
 345                         else
 346                                 cmd.opcode = MMC_READ_SINGLE_BLOCK;
 347                 } else {
 348                         if (numblocks > 1)
 349                                 cmd.opcode = MMC_WRITE_MULTIPLE_BLOCK;
 350                         else
 351                                 cmd.opcode = MMC_WRITE_BLOCK;
 352                 }
 353                 cmd.arg = block;
 354                 if (!mmc_get_high_cap(dev))
 355                         cmd.arg <<= 9;
 356                 cmd.flags = MMC_RSP_R1 | MMC_CMD_ADTC;
 357                 data.data = vaddr;
 358                 data.mrq = &req;
 359                 if (bp->b_cmd == BUF_CMD_READ)
 360                         data.flags = MMC_DATA_READ;
 361                 else
 362                         data.flags = MMC_DATA_WRITE;
 363                 data.len = numblocks * sz;
 364                 if (numblocks > 1) {
 365                         data.flags |= MMC_DATA_MULTI;
 366                         stop.opcode = MMC_STOP_TRANSMISSION;
 367                         stop.arg = 0;
 368                         stop.flags = MMC_RSP_R1B | MMC_CMD_AC;
 369                         req.stop = &stop;
 370                 }
 371 //              kprintf("Len %d  %lld-%lld flags %#x sz %d\n",
 372 //                  (int)data.len, (long long)block, (long long)end, data.flags, sz);
 373                 MMCBUS_WAIT_FOR_REQUEST(device_get_parent(dev), dev, &req);
 374                 if (req.cmd->error != MMC_ERR_NONE)
 375                         break;
 376                 block += numblocks;
 377         }
 378         return (block);
 379 }
 380
 381 static daddr_t
 382 mmcsd_delete(struct mmcsd_softc *sc, struct bio *bio)
 383 {
 384         daddr_t block, end, start, stop;
 385         struct mmc_command cmd;
 386         struct mmc_request req;
 387         device_t dev = sc->dev;
 388         int sz = sc->disk.d_info.d_media_blksize;
 389         int erase_sector;
 390         struct buf *bp = bio->bio_buf;
 391
 392         block = bio->bio_offset / sz;
 393         end = block + (bp->b_bcount / sz);
 394         /* Coalesce with part remaining from previous request. */
 395         if (block > sc->eblock && block <= sc->eend)
 396                 block = sc->eblock;
 397         if (end >= sc->eblock && end < sc->eend)
 398                 end = sc->eend;
 399         /* Safe round to the erase sector boundaries. */
 400         erase_sector = mmc_get_erase_sector(dev);
 401         start = block + erase_sector - 1;        /* Round up. */
 402         start -= start % erase_sector;
 403         stop = end;                             /* Round down. */
 404         stop -= end % erase_sector;
 405         /* We can't erase area smaller then sector, store it for later. */
 406         if (start >= stop) {
 407                 sc->eblock = block;
 408                 sc->eend = end;
 409                 return (end);
 410         }
 411
 412         /* Set erase start position. */
 413         memset(&req, 0, sizeof(req));
 414         memset(&cmd, 0, sizeof(cmd));
 415         req.cmd = &cmd;
 416         if (mmc_get_card_type(dev) == mode_sd)
 417                 cmd.opcode = SD_ERASE_WR_BLK_START;
 418         else
 419                 cmd.opcode = MMC_ERASE_GROUP_START;
 420         cmd.arg = start;
 421         if (!mmc_get_high_cap(dev))
 422                 cmd.arg <<= 9;
 423         cmd.flags = MMC_RSP_R1 | MMC_CMD_AC;
 424         MMCBUS_WAIT_FOR_REQUEST(device_get_parent(dev), dev, &req);
 425         if (req.cmd->error != MMC_ERR_NONE) {
 426             kprintf("erase err1: %d\n", req.cmd->error);
 427             return (block);
 428         }
 429         /* Set erase stop position. */
 430         memset(&req, 0, sizeof(req));
 431         memset(&cmd, 0, sizeof(cmd));
 432         req.cmd = &cmd;
 433         if (mmc_get_card_type(dev) == mode_sd)
 434                 cmd.opcode = SD_ERASE_WR_BLK_END;
 435         else
 436                 cmd.opcode = MMC_ERASE_GROUP_END;
 437         cmd.arg = stop;
 438         if (!mmc_get_high_cap(dev))
 439                 cmd.arg <<= 9;
 440         cmd.arg--;
 441         cmd.flags = MMC_RSP_R1 | MMC_CMD_AC;
 442         MMCBUS_WAIT_FOR_REQUEST(device_get_parent(dev), dev, &req);
 443         if (req.cmd->error != MMC_ERR_NONE) {
 444             kprintf("erase err2: %d\n", req.cmd->error);
 445             return (block);
 446         }
 447         /* Erase range. */
 448         memset(&req, 0, sizeof(req));
 449         memset(&cmd, 0, sizeof(cmd));
 450         req.cmd = &cmd;
 451         cmd.opcode = MMC_ERASE;
 452         cmd.arg = 0;
 453         cmd.flags = MMC_RSP_R1B | MMC_CMD_AC;
 454         MMCBUS_WAIT_FOR_REQUEST(device_get_parent(dev), dev, &req);
 455         if (req.cmd->error != MMC_ERR_NONE) {
 456             kprintf("erase err3 %d\n", req.cmd->error);
 457             return (block);
 458         }
 459         /* Store one of remaining parts for the next call. */
 460         if ((bio->bio_offset / sz) >= sc->eblock || block == start) {
 461                 sc->eblock = stop;      /* Predict next forward. */
 462                 sc->eend = end;
 463         } else {
 464                 sc->eblock = block;     /* Predict next backward. */
 465                 sc->eend = start;
 466         }
 467         return (end);
 468 }
 469
 470 static int
 471 mmcsd_dump(struct dev_dump_args *ap)
 472 {
 473 #if 0
 474         cdev_t cdev = ap->a_head.a_dev;
 475         struct mmcsd_softc *sc = (struct mmcsd_softc *)cdev->si_drv1;
 476         device_t dev = sc->dev;
 477         struct bio bp;
 478         daddr_t block, end;
 479         int length = ap->a_length;
 480
 481         /* length zero is special and really means flush buffers to media */
 482         if (!length)
 483                 return (0);
 484
 485         bzero(&bp, sizeof(struct bio));
 486         bp.bio_driver_info = cdev;
 487         bp.bio_pblkno = offset / sc->disk->d_sectorsize;
 488         bp.bio_bcount = length;
 489         bp.bio_data = virtual;
 490         bp.bio_cmd = BIO_WRITE;
 491         end = bp.bio_pblkno + bp.bio_bcount / sc->disk.d_info.d_media_blksize;
 492         MMCBUS_ACQUIRE_BUS(device_get_parent(dev), dev);
 493         block = mmcsd_rw(sc, &bp);
 494         MMCBUS_RELEASE_BUS(device_get_parent(dev), dev);
 495         return ((end < block) ? EIO : 0);
 496 #endif
 497         return EIO;
 498 }
 499
 500 static void
 501 mmcsd_task(void *arg)
 502 {
 503         struct mmcsd_softc *sc = (struct mmcsd_softc*)arg;
 504         struct bio *bio;
 505         struct buf *bp;
 506         int sz;
 507         daddr_t block, end;
 508         device_t dev;
 509
 510         dev = sc->dev;
 511
 512         while (1) {
 513                 MMCSD_LOCK(sc);
 514                 do {
 515                         if (sc->running == 0)
 516                                 goto out;
 517                         bio = bioq_takefirst(&sc->bio_queue);
 518                         if (bio == NULL)
 519                                 lksleep(sc, &sc->sc_lock, 0, "jobqueue", 0);
 520                 } while (bio == NULL);
 521                 MMCSD_UNLOCK(sc);
 522                 bp = bio->bio_buf;
 523                 devstat_start_transaction(&sc->device_stats);
 524                 if (bp->b_cmd != BUF_CMD_READ && mmc_get_read_only(dev)) {
 525                         bp->b_error = EROFS;
 526                         bp->b_resid = bp->b_bcount;
 527                         bp->b_flags |= B_ERROR;
 528                         devstat_end_transaction_buf(&sc->device_stats, bp);
 529                         biodone(bio);
 530                         continue;
 531                 }
 532                 MMCBUS_ACQUIRE_BUS(device_get_parent(dev), dev);
 533                 sz = sc->disk.d_info.d_media_blksize;
 534                 block = bio->bio_offset / sz;
 535                 end = block + (bp->b_bcount / sz);
 536                 if (bp->b_cmd == BUF_CMD_READ ||
 537                     bp->b_cmd == BUF_CMD_WRITE) {
 538                         /* Access to the remaining erase block obsoletes it. */
 539                         if (block < sc->eend && end > sc->eblock)
 540                                 sc->eblock = sc->eend = 0;
 541                         block = mmcsd_rw(sc, bio);
 542                 } else if (bp->b_cmd == BUF_CMD_FREEBLKS) {
 543                         block = mmcsd_delete(sc, bio);
 544                 }
 545                 MMCBUS_RELEASE_BUS(device_get_parent(dev), dev);
 546                 if (block < end) {
 547                         bp->b_error = EIO;
 548                         bp->b_resid = (end - block) * sz;
 549                         bp->b_flags |= B_ERROR;
 550                 } else {
 551                         bp->b_resid = 0;
 552                 }
 553                 devstat_end_transaction_buf(&sc->device_stats, bp);
 554                 biodone(bio);
 555         }
 556 out:
 557         /* tell parent we're done */
 558         sc->running = -1;
 559         MMCSD_UNLOCK(sc);
 560         wakeup(sc);
 561 }
 562
 563 static const char *
 564 mmcsd_card_name(device_t dev)
 565 {
 566         if (mmc_get_card_type(dev) == mode_mmc)
 567                 return ("MMC");
 568         if (mmc_get_high_cap(dev))
 569                 return ("SDHC");
 570         return ("SD");
 571 }
 572
 573 static int
 574 mmcsd_bus_bit_width(device_t dev)
 575 {
 576         if (mmc_get_bus_width(dev) == bus_width_1)
 577                 return (1);
 578         if (mmc_get_bus_width(dev) == bus_width_4)
 579                 return (4);
 580         return (8);
 581 }
 582
 583 static device_method_t mmcsd_methods[] = {
 584         DEVMETHOD(device_probe, mmcsd_probe),
 585         DEVMETHOD(device_attach, mmcsd_attach),
 586         DEVMETHOD(device_detach, mmcsd_detach),
 587         DEVMETHOD(device_suspend, mmcsd_suspend),
 588         DEVMETHOD(device_resume, mmcsd_resume),
 589         DEVMETHOD_END
 590 };
 591
 592 static driver_t mmcsd_driver = {
 593         "mmcsd",
 594         mmcsd_methods,
 595         sizeof(struct mmcsd_softc),
 596 };
 597 static devclass_t mmcsd_devclass;
 598
 599 DRIVER_MODULE(mmcsd, mmc, mmcsd_driver, mmcsd_devclass, NULL, NULL);