drivers/mmc/core/mmc.c

   1 /*
   2  *  linux/drivers/mmc/core/mmc.c
   3  *
   4  *  Copyright (C) 2003-2004 Russell King, All Rights Reserved.
   5  *  Copyright (C) 2005-2007 Pierre Ossman, All Rights Reserved.
   6  *  MMCv4 support Copyright (C) 2006 Philip Langdale, All Rights Reserved.
   7  *
   8  * This program is free software; you can redistribute it and/or modify
   9  * it under the terms of the GNU General Public License version 2 as
  10  * published by the Free Software Foundation.
  11  */
  12
  13 #include <linux/err.h>
  14 #include <linux/slab.h>
  15
  16 #include <linux/mmc/host.h>
  17 #include <linux/mmc/card.h>
  18 #include <linux/mmc/mmc.h>
  19
  20 #include "core.h"
  21 #include "bus.h"
  22 #include "mmc_ops.h"
  23
  24 static const unsigned int tran_exp[] = {
  25         10000,          100000,         1000000,        10000000,
  26         0,              0,              0,              0
  27 };
  28
  29 static const unsigned char tran_mant[] = {
  30         0,      10,     12,     13,     15,     20,     25,     30,
  31         35,     40,     45,     50,     55,     60,     70,     80,
  32 };
  33
  34 static const unsigned int tacc_exp[] = {
  35         1,      10,     100,    1000,   10000,  100000, 1000000, 10000000,
  36 };
  37
  38 static const unsigned int tacc_mant[] = {
  39         0,      10,     12,     13,     15,     20,     25,     30,
  40         35,     40,     45,     50,     55,     60,     70,     80,
  41 };
  42
  43 #define UNSTUFF_BITS(resp,start,size)                                   \
  44         ({                                                              \
  45                 const int __size = size;                                \
  46                 const u32 __mask = (__size < 32 ? 1 << __size : 0) - 1; \
  47                 const int __off = 3 - ((start) / 32);                   \
  48                 const int __shft = (start) & 31;                        \
  49                 u32 __res;                                              \
  50                                                                         \
  51                 __res = resp[__off] >> __shft;                          \
  52                 if (__size + __shft > 32)                               \
  53                         __res |= resp[__off-1] << ((32 - __shft) % 32); \
  54                 __res & __mask;                                         \
  55         })
  56
  57 /*
  58  * Given the decoded CSD structure, decode the raw CID to our CID structure.
  59  */
  60 static int mmc_decode_cid(struct mmc_card *card)
  61 {
  62         u32 *resp = card->raw_cid;
  63
  64         /*
  65          * The selection of the format here is based upon published
  66          * specs from sandisk and from what people have reported.
  67          */
  68         switch (card->csd.mmca_vsn) {
  69         case 0: /* MMC v1.0 - v1.2 */
  70         case 1: /* MMC v1.4 */
  71                 card->cid.manfid        = UNSTUFF_BITS(resp, 104, 24);
  72                 card->cid.prod_name[0]  = UNSTUFF_BITS(resp, 96, 8);
  73                 card->cid.prod_name[1]  = UNSTUFF_BITS(resp, 88, 8);
  74                 card->cid.prod_name[2]  = UNSTUFF_BITS(resp, 80, 8);
  75                 card->cid.prod_name[3]  = UNSTUFF_BITS(resp, 72, 8);
  76                 card->cid.prod_name[4]  = UNSTUFF_BITS(resp, 64, 8);
  77                 card->cid.prod_name[5]  = UNSTUFF_BITS(resp, 56, 8);
  78                 card->cid.prod_name[6]  = UNSTUFF_BITS(resp, 48, 8);
  79                 card->cid.hwrev         = UNSTUFF_BITS(resp, 44, 4);
  80                 card->cid.fwrev         = UNSTUFF_BITS(resp, 40, 4);
  81                 card->cid.serial        = UNSTUFF_BITS(resp, 16, 24);
  82                 card->cid.month         = UNSTUFF_BITS(resp, 12, 4);
  83                 card->cid.year          = UNSTUFF_BITS(resp, 8, 4) + 1997;
  84                 break;
  85
  86         case 2: /* MMC v2.0 - v2.2 */
  87         case 3: /* MMC v3.1 - v3.3 */
  88         case 4: /* MMC v4 */
  89                 card->cid.manfid        = UNSTUFF_BITS(resp, 120, 8);
  90                 card->cid.oemid         = UNSTUFF_BITS(resp, 104, 16);
  91                 card->cid.prod_name[0]  = UNSTUFF_BITS(resp, 96, 8);
  92                 card->cid.prod_name[1]  = UNSTUFF_BITS(resp, 88, 8);
  93                 card->cid.prod_name[2]  = UNSTUFF_BITS(resp, 80, 8);
  94                 card->cid.prod_name[3]  = UNSTUFF_BITS(resp, 72, 8);
  95                 card->cid.prod_name[4]  = UNSTUFF_BITS(resp, 64, 8);
  96                 card->cid.prod_name[5]  = UNSTUFF_BITS(resp, 56, 8);
  97                 card->cid.serial        = UNSTUFF_BITS(resp, 16, 32);
  98                 card->cid.month         = UNSTUFF_BITS(resp, 12, 4);
  99                 card->cid.year          = UNSTUFF_BITS(resp, 8, 4) + 1997;
 100                 break;
 101
 102         default:
 103                 printk(KERN_ERR "%s: card has unknown MMCA version %d\n",
 104                         mmc_hostname(card->host), card->csd.mmca_vsn);
 105                 return -EINVAL;
 106         }
 107
 108         return 0;
 109 }
 110
 111 /*
 112  * Given a 128-bit response, decode to our card CSD structure.
 113  */
 114 static int mmc_decode_csd(struct mmc_card *card)
 115 {
 116         struct mmc_csd *csd = &card->csd;
 117         unsigned int e, m, csd_struct;
 118         u32 *resp = card->raw_csd;
 119
 120         /*
 121          * We only understand CSD structure v1.1 and v1.2.
 122          * v1.2 has extra information in bits 15, 11 and 10.
 123          */
 124         csd_struct = UNSTUFF_BITS(resp, 126, 2);
 125         if (csd_struct != 1 && csd_struct != 2) {
 126                 printk(KERN_ERR "%s: unrecognised CSD structure version %d\n",
 127                         mmc_hostname(card->host), csd_struct);
 128                 return -EINVAL;
 129         }
 130
 131         csd->mmca_vsn    = UNSTUFF_BITS(resp, 122, 4);
 132         m = UNSTUFF_BITS(resp, 115, 4);
 133         e = UNSTUFF_BITS(resp, 112, 3);
 134         csd->tacc_ns     = (tacc_exp[e] * tacc_mant[m] + 9) / 10;
 135         csd->tacc_clks   = UNSTUFF_BITS(resp, 104, 8) * 100;
 136
 137         m = UNSTUFF_BITS(resp, 99, 4);
 138         e = UNSTUFF_BITS(resp, 96, 3);
 139         csd->max_dtr      = tran_exp[e] * tran_mant[m];
 140         csd->cmdclass     = UNSTUFF_BITS(resp, 84, 12);
 141
 142         e = UNSTUFF_BITS(resp, 47, 3);
 143         m = UNSTUFF_BITS(resp, 62, 12);
 144         csd->capacity     = (1 + m) << (e + 2);
 145
 146         csd->read_blkbits = UNSTUFF_BITS(resp, 80, 4);
 147         csd->read_partial = UNSTUFF_BITS(resp, 79, 1);
 148         csd->write_misalign = UNSTUFF_BITS(resp, 78, 1);
 149         csd->read_misalign = UNSTUFF_BITS(resp, 77, 1);
 150         csd->r2w_factor = UNSTUFF_BITS(resp, 26, 3);
 151         csd->write_blkbits = UNSTUFF_BITS(resp, 22, 4);
 152         csd->write_partial = UNSTUFF_BITS(resp, 21, 1);
 153
 154         return 0;
 155 }
 156
 157 /*
 158  * Read and decode extended CSD.
 159  */
 160 static int mmc_read_ext_csd(struct mmc_card *card)
 161 {
 162         int err;
 163         u8 *ext_csd;
 164
 165         BUG_ON(!card);
 166
 167         if (card->csd.mmca_vsn < CSD_SPEC_VER_4)
 168                 return 0;
 169
 170         /*
 171          * As the ext_csd is so large and mostly unused, we don't store the
 172          * raw block in mmc_card.
 173          */
 174         ext_csd = kmalloc(512, GFP_KERNEL);
 175         if (!ext_csd) {
 176                 printk(KERN_ERR "%s: could not allocate a buffer to "
 177                         "receive the ext_csd.\n", mmc_hostname(card->host));
 178                 return -ENOMEM;
 179         }
 180
 181         err = mmc_send_ext_csd(card, ext_csd);
 182         if (err) {
 183                 /* If the host or the card can't do the switch,
 184                  * fail more gracefully. */
 185                 if ((err != -EINVAL)
 186                  && (err != -ENOSYS)
 187                  && (err != -EFAULT))
 188                         goto out;
 189
 190                 /*
 191                  * High capacity cards should have this "magic" size
 192                  * stored in their CSD.
 193                  */
 194                 if (card->csd.capacity == (4096 * 512)) {
 195                         printk(KERN_ERR "%s: unable to read EXT_CSD "
 196                                 "on a possible high capacity card. "
 197                                 "Card will be ignored.\n",
 198                                 mmc_hostname(card->host));
 199                 } else {
 200                         printk(KERN_WARNING "%s: unable to read "
 201                                 "EXT_CSD, performance might "
 202                                 "suffer.\n",
 203                                 mmc_hostname(card->host));
 204                         err = 0;
 205                 }
 206
 207                 goto out;
 208         }
 209
 210         card->ext_csd.rev = ext_csd[EXT_CSD_REV];
 211         if (card->ext_csd.rev > 5) {
 212                 printk(KERN_ERR "%s: unrecognised EXT_CSD structure "
 213                         "version %d\n", mmc_hostname(card->host),
 214                         card->ext_csd.rev);
 215                 err = -EINVAL;
 216                 goto out;
 217         }
 218
 219         if (card->ext_csd.rev >= 2) {
 220                 card->ext_csd.sectors =
 221                         ext_csd[EXT_CSD_SEC_CNT + 0] << 0 |
 222                         ext_csd[EXT_CSD_SEC_CNT + 1] << 8 |
 223                         ext_csd[EXT_CSD_SEC_CNT + 2] << 16 |
 224                         ext_csd[EXT_CSD_SEC_CNT + 3] << 24;
 225                 if (card->ext_csd.sectors)
 226                         mmc_card_set_blockaddr(card);
 227         }
 228
 229         switch (ext_csd[EXT_CSD_CARD_TYPE] & EXT_CSD_CARD_TYPE_MASK) {
 230         case EXT_CSD_CARD_TYPE_52 | EXT_CSD_CARD_TYPE_26:
 231                 card->ext_csd.hs_max_dtr = 52000000;
 232                 break;
 233         case EXT_CSD_CARD_TYPE_26:
 234                 card->ext_csd.hs_max_dtr = 26000000;
 235                 break;
 236         default:
 237                 /* MMC v4 spec says this cannot happen */
 238                 printk(KERN_WARNING "%s: card is mmc v4 but doesn't "
 239                         "support any high-speed modes.\n",
 240                         mmc_hostname(card->host));
 241         }
 242
 243         if (card->ext_csd.rev >= 3) {
 244                 u8 sa_shift = ext_csd[EXT_CSD_S_A_TIMEOUT];
 245
 246                 /* Sleep / awake timeout in 100ns units */
 247                 if (sa_shift > 0 && sa_shift <= 0x17)
 248                         card->ext_csd.sa_timeout =
 249                                         1 << ext_csd[EXT_CSD_S_A_TIMEOUT];
 250         }
 251
 252 out:
 253         kfree(ext_csd);
 254
 255         return err;
 256 }
 257
 258 MMC_DEV_ATTR(cid, "%08x%08x%08x%08x\n", card->raw_cid[0], card->raw_cid[1],
 259         card->raw_cid[2], card->raw_cid[3]);
 260 MMC_DEV_ATTR(csd, "%08x%08x%08x%08x\n", card->raw_csd[0], card->raw_csd[1],
 261         card->raw_csd[2], card->raw_csd[3]);
 262 MMC_DEV_ATTR(date, "%02d/%04d\n", card->cid.month, card->cid.year);
 263 MMC_DEV_ATTR(fwrev, "0x%x\n", card->cid.fwrev);
 264 MMC_DEV_ATTR(hwrev, "0x%x\n", card->cid.hwrev);
 265 MMC_DEV_ATTR(manfid, "0x%06x\n", card->cid.manfid);
 266 MMC_DEV_ATTR(name, "%s\n", card->cid.prod_name);
 267 MMC_DEV_ATTR(oemid, "0x%04x\n", card->cid.oemid);
 268 MMC_DEV_ATTR(serial, "0x%08x\n", card->cid.serial);
 269
 270 static struct attribute *mmc_std_attrs[] = {
 271         &dev_attr_cid.attr,
 272         &dev_attr_csd.attr,
 273         &dev_attr_date.attr,
 274         &dev_attr_fwrev.attr,
 275         &dev_attr_hwrev.attr,
 276         &dev_attr_manfid.attr,
 277         &dev_attr_name.attr,
 278         &dev_attr_oemid.attr,
 279         &dev_attr_serial.attr,
 280         NULL,
 281 };
 282
 283 static struct attribute_group mmc_std_attr_group = {
 284         .attrs = mmc_std_attrs,
 285 };
 286
 287 static const struct attribute_group *mmc_attr_groups[] = {
 288         &mmc_std_attr_group,
 289         NULL,
 290 };
 291
 292 static struct device_type mmc_type = {
 293         .groups = mmc_attr_groups,
 294 };
 295
 296 /*
 297  * Handle the detection and initialisation of a card.
 298  *
 299  * In the case of a resume, "oldcard" will contain the card
 300  * we're trying to reinitialise.
 301  */
 302 static int mmc_init_card(struct mmc_host *host, u32 ocr,
 303         struct mmc_card *oldcard)
 304 {
 305         struct mmc_card *card;
 306         int err;
 307         u32 cid[4];
 308         unsigned int max_dtr;
 309
 310         BUG_ON(!host);
 311         WARN_ON(!host->claimed);
 312
 313         /*
 314          * Since we're changing the OCR value, we seem to
 315          * need to tell some cards to go back to the idle
 316          * state.  We wait 1ms to give cards time to
 317          * respond.
 318          */
 319         mmc_go_idle(host);
 320
 321         /* The extra bit indicates that we support high capacity */
 322         err = mmc_send_op_cond(host, ocr | (1 << 30), NULL);
 323         if (err)
 324                 goto err;
 325
 326         /*
 327          * For SPI, enable CRC as appropriate.
 328          */
 329         if (mmc_host_is_spi(host)) {
 330                 err = mmc_spi_set_crc(host, use_spi_crc);
 331                 if (err)
 332                         goto err;
 333         }
 334
 335         /*
 336          * Fetch CID from card.
 337          */
 338         if (mmc_host_is_spi(host))
 339                 err = mmc_send_cid(host, cid);
 340         else
 341                 err = mmc_all_send_cid(host, cid);
 342         if (err)
 343                 goto err;
 344
 345         if (oldcard) {
 346                 if (memcmp(cid, oldcard->raw_cid, sizeof(cid)) != 0) {
 347                         err = -ENOENT;
 348                         goto err;
 349                 }
 350
 351                 card = oldcard;
 352         } else {
 353                 /*
 354                  * Allocate card structure.
 355                  */
 356                 card = mmc_alloc_card(host, &mmc_type);
 357                 if (IS_ERR(card)) {
 358                         err = PTR_ERR(card);
 359                         goto err;
 360                 }
 361
 362                 card->type = MMC_TYPE_MMC;
 363                 card->rca = 1;
 364                 memcpy(card->raw_cid, cid, sizeof(card->raw_cid));
 365         }
 366
 367         /*
 368          * For native busses:  set card RCA and quit open drain mode.
 369          */
 370         if (!mmc_host_is_spi(host)) {
 371                 err = mmc_set_relative_addr(card);
 372                 if (err)
 373                         goto free_card;
 374
 375                 mmc_set_bus_mode(host, MMC_BUSMODE_PUSHPULL);
 376         }
 377
 378         if (!oldcard) {
 379                 /*
 380                  * Fetch CSD from card.
 381                  */
 382                 err = mmc_send_csd(card, card->raw_csd);
 383                 if (err)
 384                         goto free_card;
 385
 386                 err = mmc_decode_csd(card);
 387                 if (err)
 388                         goto free_card;
 389                 err = mmc_decode_cid(card);
 390                 if (err)
 391                         goto free_card;
 392         }
 393
 394         /*
 395          * Select card, as all following commands rely on that.
 396          */
 397         if (!mmc_host_is_spi(host)) {
 398                 err = mmc_select_card(card);
 399                 if (err)
 400                         goto free_card;
 401         }
 402
 403         if (!oldcard) {
 404                 /*
 405                  * Fetch and process extended CSD.
 406                  */
 407                 err = mmc_read_ext_csd(card);
 408                 if (err)
 409                         goto free_card;
 410         }
 411
 412         /*
 413          * Activate high speed (if supported)
 414          */
 415         if ((card->ext_csd.hs_max_dtr != 0) &&
 416                 (host->caps & MMC_CAP_MMC_HIGHSPEED)) {
 417                 err = mmc_switch(card, EXT_CSD_CMD_SET_NORMAL,
 418                         EXT_CSD_HS_TIMING, 1);
 419                 if (err && err != -EBADMSG)
 420                         goto free_card;
 421
 422                 if (err) {
 423                         printk(KERN_WARNING "%s: switch to highspeed failed\n",
 424                                mmc_hostname(card->host));
 425                         err = 0;
 426                 } else {
 427                         mmc_card_set_highspeed(card);
 428                         mmc_set_timing(card->host, MMC_TIMING_MMC_HS);
 429                 }
 430         }
 431
 432         /*
 433          * Compute bus speed.
 434          */
 435         max_dtr = (unsigned int)-1;
 436
 437         if (mmc_card_highspeed(card)) {
 438                 if (max_dtr > card->ext_csd.hs_max_dtr)
 439                         max_dtr = card->ext_csd.hs_max_dtr;
 440         } else if (max_dtr > card->csd.max_dtr) {
 441                 max_dtr = card->csd.max_dtr;
 442         }
 443
 444         mmc_set_clock(host, max_dtr);
 445
 446         /*
 447          * Activate wide bus (if supported).
 448          */
 449         if ((card->csd.mmca_vsn >= CSD_SPEC_VER_4) &&
 450             (host->caps & (MMC_CAP_4_BIT_DATA | MMC_CAP_8_BIT_DATA))) {
 451                 unsigned ext_csd_bit, bus_width;
 452
 453                 if (host->caps & MMC_CAP_8_BIT_DATA) {
 454                         ext_csd_bit = EXT_CSD_BUS_WIDTH_8;
 455                         bus_width = MMC_BUS_WIDTH_8;
 456                 } else {
 457                         ext_csd_bit = EXT_CSD_BUS_WIDTH_4;
 458                         bus_width = MMC_BUS_WIDTH_4;
 459                 }
 460
 461                 err = mmc_switch(card, EXT_CSD_CMD_SET_NORMAL,
 462                                  EXT_CSD_BUS_WIDTH, ext_csd_bit);
 463
 464                 if (err && err != -EBADMSG)
 465                         goto free_card;
 466
 467                 if (err) {
 468                         printk(KERN_WARNING "%s: switch to bus width %d "
 469                                "failed\n", mmc_hostname(card->host),
 470                                1 << bus_width);
 471                         err = 0;
 472                 } else {
 473                         mmc_set_bus_width(card->host, bus_width);
 474                 }
 475         }
 476
 477         if (!oldcard)
 478                 host->card = card;
 479
 480         return 0;
 481
 482 free_card:
 483         if (!oldcard)
 484                 mmc_remove_card(card);
 485 err:
 486
 487         return err;
 488 }
 489
 490 /*
 491  * Host is being removed. Free up the current card.
 492  */
 493 static void mmc_remove(struct mmc_host *host)
 494 {
 495         BUG_ON(!host);
 496         BUG_ON(!host->card);
 497
 498         mmc_remove_card(host->card);
 499         host->card = NULL;
 500 }
 501
 502 /*
 503  * Card detection callback from host.
 504  */
 505 static void mmc_detect(struct mmc_host *host)
 506 {
 507         int err;
 508
 509         BUG_ON(!host);
 510         BUG_ON(!host->card);
 511
 512         mmc_claim_host(host);
 513
 514         /*
 515          * Just check if our card has been removed.
 516          */
 517         err = mmc_send_status(host->card, NULL);
 518
 519         mmc_release_host(host);
 520
 521         if (err) {
 522                 mmc_remove(host);
 523
 524                 mmc_claim_host(host);
 525                 mmc_detach_bus(host);
 526                 mmc_release_host(host);
 527         }
 528 }
 529
 530 /*
 531  * Suspend callback from host.
 532  */
 533 static int mmc_suspend(struct mmc_host *host)
 534 {
 535         BUG_ON(!host);
 536         BUG_ON(!host->card);
 537
 538         mmc_claim_host(host);
 539         if (!mmc_host_is_spi(host))
 540                 mmc_deselect_cards(host);
 541         host->card->state &= ~MMC_STATE_HIGHSPEED;
 542         mmc_release_host(host);
 543
 544         return 0;
 545 }
 546
 547 /*
 548  * Resume callback from host.
 549  *
 550  * This function tries to determine if the same card is still present
 551  * and, if so, restore all state to it.
 552  */
 553 static int mmc_resume(struct mmc_host *host)
 554 {
 555         int err;
 556
 557         BUG_ON(!host);
 558         BUG_ON(!host->card);
 559
 560         mmc_claim_host(host);
 561         err = mmc_init_card(host, host->ocr, host->card);
 562         mmc_release_host(host);
 563
 564         return err;
 565 }
 566
 567 static void mmc_power_restore(struct mmc_host *host)
 568 {
 569         host->card->state &= ~MMC_STATE_HIGHSPEED;
 570         mmc_claim_host(host);
 571         mmc_init_card(host, host->ocr, host->card);
 572         mmc_release_host(host);
 573 }
 574
 575 static int mmc_sleep(struct mmc_host *host)
 576 {
 577         struct mmc_card *card = host->card;
 578         int err = -ENOSYS;
 579
 580         if (card && card->ext_csd.rev >= 3) {
 581                 err = mmc_card_sleepawake(host, 1);
 582                 if (err < 0)
 583                         pr_debug("%s: Error %d while putting card into sleep",
 584                                  mmc_hostname(host), err);
 585         }
 586
 587         return err;
 588 }
 589
 590 static int mmc_awake(struct mmc_host *host)
 591 {
 592         struct mmc_card *card = host->card;
 593         int err = -ENOSYS;
 594
 595         if (card && card->ext_csd.rev >= 3) {
 596                 err = mmc_card_sleepawake(host, 0);
 597                 if (err < 0)
 598                         pr_debug("%s: Error %d while awaking sleeping card",
 599                                  mmc_hostname(host), err);
 600         }
 601
 602         return err;
 603 }
 604
 605 static const struct mmc_bus_ops mmc_ops = {
 606         .awake = mmc_awake,
 607         .sleep = mmc_sleep,
 608         .remove = mmc_remove,
 609         .detect = mmc_detect,
 610         .suspend = NULL,
 611         .resume = NULL,
 612         .power_restore = mmc_power_restore,
 613 };
 614
 615 static const struct mmc_bus_ops mmc_ops_unsafe = {
 616         .awake = mmc_awake,
 617         .sleep = mmc_sleep,
 618         .remove = mmc_remove,
 619         .detect = mmc_detect,
 620         .suspend = mmc_suspend,
 621         .resume = mmc_resume,
 622         .power_restore = mmc_power_restore,
 623 };
 624
 625 static void mmc_attach_bus_ops(struct mmc_host *host)
 626 {
 627         const struct mmc_bus_ops *bus_ops;
 628
 629         if (host->caps & MMC_CAP_NONREMOVABLE || !mmc_assume_removable)
 630                 bus_ops = &mmc_ops_unsafe;
 631         else
 632                 bus_ops = &mmc_ops;
 633         mmc_attach_bus(host, bus_ops);
 634 }
 635
 636 /*
 637  * Starting point for MMC card init.
 638  */
 639 int mmc_attach_mmc(struct mmc_host *host, u32 ocr)
 640 {
 641         int err;
 642
 643         BUG_ON(!host);
 644         WARN_ON(!host->claimed);
 645
 646         mmc_attach_bus_ops(host);
 647
 648         /*
 649          * We need to get OCR a different way for SPI.
 650          */
 651         if (mmc_host_is_spi(host)) {
 652                 err = mmc_spi_read_ocr(host, 1, &ocr);
 653                 if (err)
 654                         goto err;
 655         }
 656
 657         /*
 658          * Sanity check the voltages that the card claims to
 659          * support.
 660          */
 661         if (ocr & 0x7F) {
 662                 printk(KERN_WARNING "%s: card claims to support voltages "
 663                        "below the defined range. These will be ignored.\n",
 664                        mmc_hostname(host));
 665                 ocr &= ~0x7F;
 666         }
 667
 668         host->ocr = mmc_select_voltage(host, ocr);
 669
 670         /*
 671          * Can we support the voltage of the card?
 672          */
 673         if (!host->ocr) {
 674                 err = -EINVAL;
 675                 goto err;
 676         }
 677
 678         /*
 679          * Detect and init the card.
 680          */
 681         err = mmc_init_card(host, host->ocr, NULL);
 682         if (err)
 683                 goto err;
 684
 685         mmc_release_host(host);
 686
 687         err = mmc_add_card(host->card);
 688         if (err)
 689                 goto remove_card;
 690
 691         return 0;
 692
 693 remove_card:
 694         mmc_remove_card(host->card);
 695         host->card = NULL;
 696         mmc_claim_host(host);
 697 err:
 698         mmc_detach_bus(host);
 699         mmc_release_host(host);
 700
 701         printk(KERN_ERR "%s: error %d whilst initialising MMC card\n",
 702                 mmc_hostname(host), err);
 703
 704         return err;
 705 }