drivers/mmc/core/sd.c

   1 /*
   2  *  linux/drivers/mmc/core/sd.c
   3  *
   4  *  Copyright (C) 2003-2004 Russell King, All Rights Reserved.
   5  *  SD support Copyright (C) 2004 Ian Molton, All Rights Reserved.
   6  *  Copyright (C) 2005-2007 Pierre Ossman, 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
  15 #include <linux/mmc/host.h>
  16 #include <linux/mmc/card.h>
  17 #include <linux/mmc/mmc.h>
  18 #include <linux/mmc/sd.h>
  19
  20 #include "core.h"
  21 #include "sysfs.h"
  22 #include "bus.h"
  23 #include "mmc_ops.h"
  24 #include "sd_ops.h"
  25
  26 static const unsigned int tran_exp[] = {
  27         10000,          100000,         1000000,        10000000,
  28         0,              0,              0,              0
  29 };
  30
  31 static const unsigned char tran_mant[] = {
  32         0,      10,     12,     13,     15,     20,     25,     30,
  33         35,     40,     45,     50,     55,     60,     70,     80,
  34 };
  35
  36 static const unsigned int tacc_exp[] = {
  37         1,      10,     100,    1000,   10000,  100000, 1000000, 10000000,
  38 };
  39
  40 static const unsigned int tacc_mant[] = {
  41         0,      10,     12,     13,     15,     20,     25,     30,
  42         35,     40,     45,     50,     55,     60,     70,     80,
  43 };
  44
  45 #if 0   // mask by Victor Yu. 12-03-2008
  46 #define UNSTUFF_BITS(resp,start,size)                                   \
  47         ({                                                              \
  48                 const int __size = size;                                \
  49                 const u32 __mask = (__size < 32 ? 1 << __size : 0) - 1; \
  50                 const int __off = 3 - ((start) / 32);                   \
  51                 const int __shft = (start) & 31;                        \
  52                 u32 __res;                                              \
  53                                                                         \
  54                 __res = resp[__off] >> __shft;                          \
  55                 if (__size + __shft > 32)                               \
  56                         __res |= resp[__off-1] << ((32 - __shft) % 32); \
  57                 __res & __mask;                                         \
  58         })
  59 #else
  60 #define UNSTUFF_BITS(resp,start,size)                                   \
  61         ({                                                              \
  62                 const int __size = size;                                \
  63                 const u32 __mask = (__size < 32 ? 1 << __size : 0) - 1; \
  64                 const int __off = ((start) / 32);                       \
  65                 const int __shft = (start) & 31;                        \
  66                 u32 __res;                                              \
  67                                                                         \
  68                 __res = resp[__off] >> __shft;                          \
  69                 if (__size + __shft > 32)                               \
  70                         __res |= resp[__off+1] << ((32 - __shft) % 32); \
  71                 __res & __mask;                                         \
  72         })
  73 #endif
  74
  75 /*
  76  * Given the decoded CSD structure, decode the raw CID to our CID structure.
  77  */
  78 static void mmc_decode_cid(struct mmc_card *card)
  79 {
  80         u32 *resp = card->raw_cid;
  81
  82         memset(&card->cid, 0, sizeof(struct mmc_cid));
  83
  84         /*
  85          * SD doesn't currently have a version field so we will
  86          * have to assume we can parse this.
  87          */
  88         card->cid.manfid                = UNSTUFF_BITS(resp, 120, 8);
  89         card->cid.oemid                 = UNSTUFF_BITS(resp, 104, 16);
  90         card->cid.prod_name[0]          = UNSTUFF_BITS(resp, 96, 8);
  91         card->cid.prod_name[1]          = UNSTUFF_BITS(resp, 88, 8);
  92         card->cid.prod_name[2]          = UNSTUFF_BITS(resp, 80, 8);
  93         card->cid.prod_name[3]          = UNSTUFF_BITS(resp, 72, 8);
  94         card->cid.prod_name[4]          = UNSTUFF_BITS(resp, 64, 8);
  95         card->cid.hwrev                 = UNSTUFF_BITS(resp, 60, 4);
  96         card->cid.fwrev                 = UNSTUFF_BITS(resp, 56, 4);
  97         card->cid.serial                = UNSTUFF_BITS(resp, 24, 32);
  98         card->cid.year                  = UNSTUFF_BITS(resp, 12, 8);
  99         card->cid.month                 = UNSTUFF_BITS(resp, 8, 4);
 100
 101         card->cid.year += 2000; /* SD cards year offset */
 102 }
 103
 104 /*
 105  * Given a 128-bit response, decode to our card CSD structure.
 106  */
 107 static int mmc_decode_csd(struct mmc_card *card)
 108 {
 109         struct mmc_csd *csd = &card->csd;
 110         unsigned int e, m, csd_struct;
 111         u32 *resp = card->raw_csd;
 112
 113         csd_struct = UNSTUFF_BITS(resp, 126, 2);
 114
 115         switch (csd_struct) {
 116         case 0:
 117                 m = UNSTUFF_BITS(resp, 115, 4);
 118                 e = UNSTUFF_BITS(resp, 112, 3);
 119                 csd->tacc_ns     = (tacc_exp[e] * tacc_mant[m] + 9) / 10;
 120                 csd->tacc_clks   = UNSTUFF_BITS(resp, 104, 8) * 100;
 121
 122                 m = UNSTUFF_BITS(resp, 99, 4);
 123                 e = UNSTUFF_BITS(resp, 96, 3);
 124                 csd->max_dtr      = tran_exp[e] * tran_mant[m];
 125                 csd->cmdclass     = UNSTUFF_BITS(resp, 84, 12);
 126
 127                 e = UNSTUFF_BITS(resp, 47, 3);
 128                 m = UNSTUFF_BITS(resp, 62, 12);
 129                 csd->capacity     = (1 + m) << (e + 2);
 130
 131                 csd->read_blkbits = UNSTUFF_BITS(resp, 80, 4);
 132                 csd->read_partial = UNSTUFF_BITS(resp, 79, 1);
 133                 csd->write_misalign = UNSTUFF_BITS(resp, 78, 1);
 134                 csd->read_misalign = UNSTUFF_BITS(resp, 77, 1);
 135                 csd->r2w_factor = UNSTUFF_BITS(resp, 26, 3);
 136                 csd->write_blkbits = UNSTUFF_BITS(resp, 22, 4);
 137                 csd->write_partial = UNSTUFF_BITS(resp, 21, 1);
 138                 break;
 139         case 1:
 140                 /*
 141                  * This is a block-addressed SDHC card. Most
 142                  * interesting fields are unused and have fixed
 143                  * values. To avoid getting tripped by buggy cards,
 144                  * we assume those fixed values ourselves.
 145                  */
 146                 mmc_card_set_blockaddr(card);
 147
 148                 csd->tacc_ns     = 0; /* Unused */
 149                 csd->tacc_clks   = 0; /* Unused */
 150
 151                 m = UNSTUFF_BITS(resp, 99, 4);
 152                 e = UNSTUFF_BITS(resp, 96, 3);
 153                 csd->max_dtr      = tran_exp[e] * tran_mant[m];
 154                 csd->cmdclass     = UNSTUFF_BITS(resp, 84, 12);
 155
 156                 m = UNSTUFF_BITS(resp, 48, 22);
 157                 csd->capacity     = (1 + m) << 10;
 158
 159                 csd->read_blkbits = 9;
 160                 csd->read_partial = 0;
 161                 csd->write_misalign = 0;
 162                 csd->read_misalign = 0;
 163                 csd->r2w_factor = 4; /* Unused */
 164                 csd->write_blkbits = 9;
 165                 csd->write_partial = 0;
 166                 break;
 167         default:
 168                 printk(KERN_ERR "%s: unrecognised CSD structure version %d\n",
 169                         mmc_hostname(card->host), csd_struct);
 170                 return -EINVAL;
 171         }
 172
 173         return 0;
 174 }
 175
 176 /*
 177  * Given a 64-bit response, decode to our card SCR structure.
 178  */
 179 static int mmc_decode_scr(struct mmc_card *card)
 180 {
 181         struct sd_scr *scr = &card->scr;
 182         unsigned int scr_struct;
 183         u32 resp[4];
 184
 185         BUG_ON(!mmc_card_sd(card));
 186
 187         resp[3] = card->raw_scr[1];
 188         resp[2] = card->raw_scr[0];
 189 #if 1   // add by Victor Yu. 12-03-2008
 190         resp[0] = 0;
 191         resp[1] = 0;
 192 #endif
 193
 194         scr_struct = UNSTUFF_BITS(resp, 60, 4);
 195         if (scr_struct != 0) {
 196                 printk(KERN_ERR "%s: unrecognised SCR structure version %d\n",
 197                         mmc_hostname(card->host), scr_struct);
 198                 return -EINVAL;
 199         }
 200
 201         scr->sda_vsn = UNSTUFF_BITS(resp, 56, 4);
 202         scr->bus_widths = UNSTUFF_BITS(resp, 48, 4);
 203
 204         return 0;
 205 }
 206
 207 /*
 208  * Fetches and decodes switch information
 209  */
 210 static int mmc_read_switch(struct mmc_card *card)
 211 {
 212         int err;
 213         u8 *status;
 214
 215         if (card->scr.sda_vsn < SCR_SPEC_VER_1)
 216                 return MMC_ERR_NONE;
 217
 218         if (!(card->csd.cmdclass & CCC_SWITCH)) {
 219                 printk(KERN_WARNING "%s: card lacks mandatory switch "
 220                         "function, performance might suffer.\n",
 221                         mmc_hostname(card->host));
 222                 return MMC_ERR_NONE;
 223         }
 224
 225         err = MMC_ERR_FAILED;
 226
 227         status = kmalloc(64, GFP_KERNEL);
 228         if (!status) {
 229                 printk(KERN_ERR "%s: could not allocate a buffer for "
 230                         "switch capabilities.\n", mmc_hostname(card->host));
 231                 return err;
 232         }
 233
 234         err = mmc_sd_switch(card, 0, 0, 1, status);
 235         if (err != MMC_ERR_NONE) {
 236                 printk(KERN_WARNING "%s: problem reading switch "
 237                         "capabilities, performance might suffer.\n",
 238                         mmc_hostname(card->host));
 239                 err = MMC_ERR_NONE;
 240                 goto out;
 241         }
 242
 243         if (status[13] & 0x02)
 244                 card->sw_caps.hs_max_dtr = 50000000;
 245
 246 out:
 247         kfree(status);
 248
 249         return err;
 250 }
 251
 252 /*
 253  * Test if the card supports high-speed mode and, if so, switch to it.
 254  */
 255 static int mmc_switch_hs(struct mmc_card *card)
 256 {
 257         int err;
 258         u8 *status;
 259
 260         if (card->scr.sda_vsn < SCR_SPEC_VER_1)
 261                 return MMC_ERR_NONE;
 262
 263         if (!(card->csd.cmdclass & CCC_SWITCH))
 264                 return MMC_ERR_NONE;
 265
 266         if (!(card->host->caps & MMC_CAP_SD_HIGHSPEED))
 267                 return MMC_ERR_NONE;
 268
 269         if (card->sw_caps.hs_max_dtr == 0)
 270                 return MMC_ERR_NONE;
 271
 272         err = MMC_ERR_FAILED;
 273
 274         status = kmalloc(64, GFP_KERNEL);
 275         if (!status) {
 276                 printk(KERN_ERR "%s: could not allocate a buffer for "
 277                         "switch capabilities.\n", mmc_hostname(card->host));
 278                 return err;
 279         }
 280
 281         err = mmc_sd_switch(card, 1, 0, 1, status);
 282         if (err != MMC_ERR_NONE)
 283                 goto out;
 284
 285         if ((status[16] & 0xF) != 1) {
 286                 printk(KERN_WARNING "%s: Problem switching card "
 287                         "into high-speed mode!\n",
 288                         mmc_hostname(card->host));
 289         } else {
 290                 mmc_card_set_highspeed(card);
 291                 mmc_set_timing(card->host, MMC_TIMING_SD_HS);
 292         }
 293
 294 out:
 295         kfree(status);
 296
 297         return err;
 298 }
 299
 300 /*
 301  * Handle the detection and initialisation of a card.
 302  *
 303  * In the case of a resume, "curcard" will contain the card
 304  * we're trying to reinitialise.
 305  */
 306 static int mmc_sd_init_card(struct mmc_host *host, u32 ocr,
 307         struct mmc_card *oldcard)
 308 {
 309         struct mmc_card *card;
 310         int err;
 311         u32 cid[4];
 312         unsigned int max_dtr;
 313
 314         BUG_ON(!host);
 315         BUG_ON(!host->claimed);
 316
 317         /*
 318          * Since we're changing the OCR value, we seem to
 319          * need to tell some cards to go back to the idle
 320          * state.  We wait 1ms to give cards time to
 321          * respond.
 322          */
 323         mmc_go_idle(host);
 324
 325         /*
 326          * If SD_SEND_IF_COND indicates an SD 2.0
 327          * compliant card and we should set bit 30
 328          * of the ocr to indicate that we can handle
 329          * block-addressed SDHC cards.
 330          */
 331         err = mmc_send_if_cond(host, ocr);
 332         if (err == MMC_ERR_NONE)
 333                 ocr |= 1 << 30;
 334
 335         err = mmc_send_app_op_cond(host, ocr, NULL);
 336         if (err != MMC_ERR_NONE){
 337                 printk(KERN_WARNING  "mmc_send_app_op_cond error");
 338                 goto err;
 339         }
 340
 341         /*
 342          * Fetch CID from card.
 343          */
 344         err = mmc_all_send_cid(host, cid);
 345         if (err != MMC_ERR_NONE){
 346                 printk(KERN_WARNING  "mmc_all_send_cid error");
 347                 goto err;
 348         }
 349
 350         if (oldcard) {
 351                 if (memcmp(cid, oldcard->raw_cid, sizeof(cid)) != 0){
 352                         printk(KERN_WARNING  "mmc oldcard memcmp error");
 353                         goto err;
 354                 }
 355
 356                 card = oldcard;
 357         } else {
 358                 /*
 359                  * Allocate card structure.
 360                  */
 361                 card = mmc_alloc_card(host);
 362                 if (IS_ERR(card)){
 363                         printk(KERN_WARNING  "mmc_alloc_card error");
 364                         goto err;
 365                 }
 366
 367                 card->type = MMC_TYPE_SD;
 368                 memcpy(card->raw_cid, cid, sizeof(card->raw_cid));
 369         }
 370
 371         /*
 372          * Set card RCA.
 373          */
 374         err = mmc_send_relative_addr(host, &card->rca);
 375         if (err != MMC_ERR_NONE)
 376                 goto free_card;
 377
 378         mmc_set_bus_mode(host, MMC_BUSMODE_PUSHPULL);
 379
 380         if (!oldcard) {
 381                 /*
 382                  * Fetch CSD from card.
 383                  */
 384                 err = mmc_send_csd(card, card->raw_csd);
 385                 if (err != MMC_ERR_NONE)
 386                         goto free_card;
 387
 388                 err = mmc_decode_csd(card);
 389                 if (err < 0)
 390                         goto free_card;
 391
 392                 mmc_decode_cid(card);
 393         }
 394
 395         /*
 396          * Select card, as all following commands rely on that.
 397          */
 398         err = mmc_select_card(card);
 399         if (err != MMC_ERR_NONE)
 400                 goto free_card;
 401
 402         if (!oldcard) {
 403                 /*
 404                  * Fetch SCR from card.
 405                  */
 406                 err = mmc_app_send_scr(card, card->raw_scr);
 407                 if (err != MMC_ERR_NONE)
 408                         goto free_card;
 409
 410                 err = mmc_decode_scr(card);
 411                 if (err < 0)
 412                         goto free_card;
 413
 414                 /*
 415                  * Fetch switch information from card.
 416                  */
 417                 err = mmc_read_switch(card);
 418                 if (err != MMC_ERR_NONE)
 419                         goto free_card;
 420         }
 421
 422         /*
 423          * Attempt to change to high-speed (if supported)
 424          */
 425         err = mmc_switch_hs(card);
 426         if (err != MMC_ERR_NONE)
 427                 goto free_card;
 428
 429         /*
 430          * Compute bus speed.
 431          */
 432         max_dtr = (unsigned int)-1;
 433
 434         if (mmc_card_highspeed(card)) {
 435                 if (max_dtr > card->sw_caps.hs_max_dtr)
 436                         max_dtr = card->sw_caps.hs_max_dtr;
 437         } else if (max_dtr > card->csd.max_dtr) {
 438                 max_dtr = card->csd.max_dtr;
 439         }
 440
 441         mmc_set_clock(host, max_dtr);
 442
 443         /*
 444          * Switch to wider bus (if supported).
 445          */
 446         if ((host->caps & MMC_CAP_4_BIT_DATA) &&
 447                 (card->scr.bus_widths & SD_SCR_BUS_WIDTH_4)) {
 448                 err = mmc_app_set_bus_width(card, MMC_BUS_WIDTH_4);
 449                 if (err != MMC_ERR_NONE)
 450                         goto free_card;
 451
 452                 mmc_set_bus_width(host, MMC_BUS_WIDTH_4);
 453         }
 454
 455         /*
 456          * Check if read-only switch is active.
 457          */
 458         if (!oldcard) {
 459                 if (!host->ops->get_ro) {
 460                         printk(KERN_WARNING "%s: host does not "
 461                                 "support reading read-only "
 462                                 "switch. assuming write-enable.\n",
 463                                 mmc_hostname(host));
 464                 } else {
 465                         if (host->ops->get_ro(host))
 466                                 mmc_card_set_readonly(card);
 467                 }
 468         }
 469
 470         if (!oldcard)
 471                 host->card = card;
 472
 473         return MMC_ERR_NONE;
 474
 475 free_card:
 476         if (!oldcard)
 477                 mmc_remove_card(card);
 478 err:
 479
 480         return MMC_ERR_FAILED;
 481 }
 482
 483 /*
 484  * Host is being removed. Free up the current card.
 485  */
 486 static void mmc_sd_remove(struct mmc_host *host)
 487 {
 488         BUG_ON(!host);
 489         BUG_ON(!host->card);
 490
 491         mmc_remove_card(host->card);
 492         host->card = NULL;
 493 }
 494
 495 /*
 496  * Card detection callback from host.
 497  */
 498 static void mmc_sd_detect(struct mmc_host *host)
 499 {
 500         int err;
 501
 502         BUG_ON(!host);
 503         BUG_ON(!host->card);
 504
 505         mmc_claim_host(host);
 506
 507         /*
 508          * Just check if our card has been removed.
 509          */
 510         err = mmc_send_status(host->card, NULL);
 511
 512         mmc_release_host(host);
 513
 514         if (err != MMC_ERR_NONE) {
 515                 mmc_sd_remove(host);
 516
 517                 mmc_claim_host(host);
 518                 mmc_detach_bus(host);
 519                 mmc_release_host(host);
 520         }
 521 }
 522
 523 MMC_ATTR_FN(cid, "%08x%08x%08x%08x\n", card->raw_cid[0], card->raw_cid[1],
 524         card->raw_cid[2], card->raw_cid[3]);
 525 MMC_ATTR_FN(csd, "%08x%08x%08x%08x\n", card->raw_csd[0], card->raw_csd[1],
 526         card->raw_csd[2], card->raw_csd[3]);
 527 MMC_ATTR_FN(scr, "%08x%08x\n", card->raw_scr[0], card->raw_scr[1]);
 528 MMC_ATTR_FN(date, "%02d/%04d\n", card->cid.month, card->cid.year);
 529 MMC_ATTR_FN(fwrev, "0x%x\n", card->cid.fwrev);
 530 MMC_ATTR_FN(hwrev, "0x%x\n", card->cid.hwrev);
 531 MMC_ATTR_FN(manfid, "0x%06x\n", card->cid.manfid);
 532 MMC_ATTR_FN(name, "%s\n", card->cid.prod_name);
 533 MMC_ATTR_FN(oemid, "0x%04x\n", card->cid.oemid);
 534 MMC_ATTR_FN(serial, "0x%08x\n", card->cid.serial);
 535
 536 static struct device_attribute mmc_sd_dev_attrs[] = {
 537         MMC_ATTR_RO(cid),
 538         MMC_ATTR_RO(csd),
 539         MMC_ATTR_RO(scr),
 540         MMC_ATTR_RO(date),
 541         MMC_ATTR_RO(fwrev),
 542         MMC_ATTR_RO(hwrev),
 543         MMC_ATTR_RO(manfid),
 544         MMC_ATTR_RO(name),
 545         MMC_ATTR_RO(oemid),
 546         MMC_ATTR_RO(serial),
 547         __ATTR_NULL,
 548 };
 549
 550 /*
 551  * Adds sysfs entries as relevant.
 552  */
 553 static int mmc_sd_sysfs_add(struct mmc_host *host, struct mmc_card *card)
 554 {
 555         int ret;
 556
 557         ret = mmc_add_attrs(card, mmc_sd_dev_attrs);
 558         if (ret < 0)
 559                 return ret;
 560
 561         return 0;
 562 }
 563
 564 /*
 565  * Removes the sysfs entries added by mmc_sysfs_add().
 566  */
 567 static void mmc_sd_sysfs_remove(struct mmc_host *host, struct mmc_card *card)
 568 {
 569         mmc_remove_attrs(card, mmc_sd_dev_attrs);
 570 }
 571
 572 #ifdef CONFIG_MMC_UNSAFE_RESUME
 573
 574 /*
 575  * Suspend callback from host.
 576  */
 577 static void mmc_sd_suspend(struct mmc_host *host)
 578 {
 579         BUG_ON(!host);
 580         BUG_ON(!host->card);
 581
 582         mmc_claim_host(host);
 583         mmc_deselect_cards(host);
 584         host->card->state &= ~MMC_STATE_HIGHSPEED;
 585         mmc_release_host(host);
 586 }
 587
 588 /*
 589  * Resume callback from host.
 590  *
 591  * This function tries to determine if the same card is still present
 592  * and, if so, restore all state to it.
 593  */
 594 static void mmc_sd_resume(struct mmc_host *host)
 595 {
 596         int err;
 597
 598         BUG_ON(!host);
 599         BUG_ON(!host->card);
 600
 601         mmc_claim_host(host);
 602         err = mmc_sd_init_card(host, host->ocr, host->card);
 603         mmc_release_host(host);
 604
 605         if (err != MMC_ERR_NONE) {
 606                 mmc_sd_remove(host);
 607
 608                 mmc_claim_host(host);
 609                 mmc_detach_bus(host);
 610                 mmc_release_host(host);
 611         }
 612
 613 }
 614
 615 #else
 616
 617 #define mmc_sd_suspend NULL
 618 #define mmc_sd_resume NULL
 619
 620 #endif
 621
 622 static const struct mmc_bus_ops mmc_sd_ops = {
 623         .remove = mmc_sd_remove,
 624         .detect = mmc_sd_detect,
 625         .sysfs_add = mmc_sd_sysfs_add,
 626         .sysfs_remove = mmc_sd_sysfs_remove,
 627         .suspend = mmc_sd_suspend,
 628         .resume = mmc_sd_resume,
 629 };
 630
 631 /*
 632  * Starting point for SD card init.
 633  */
 634 int mmc_attach_sd(struct mmc_host *host, u32 ocr)
 635 {
 636         int err;
 637
 638         BUG_ON(!host);
 639         BUG_ON(!host->claimed);
 640
 641         mmc_attach_bus(host, &mmc_sd_ops);
 642
 643         /*
 644          * Sanity check the voltages that the card claims to
 645          * support.
 646          */
 647         if (ocr & 0x7F) {
 648                 printk(KERN_WARNING "%s: card claims to support voltages "
 649                        "below the defined range. These will be ignored.\n",
 650                        mmc_hostname(host));
 651                 ocr &= ~0x7F;
 652         }
 653
 654         if (ocr & MMC_VDD_165_195) {
 655                 printk(KERN_WARNING "%s: SD card claims to support the "
 656                        "incompletely defined 'low voltage range'. This "
 657                        "will be ignored.\n", mmc_hostname(host));
 658                 ocr &= ~MMC_VDD_165_195;
 659         }
 660
 661         host->ocr = mmc_select_voltage(host, ocr);
 662
 663         /*
 664          * Can we support the voltage(s) of the card(s)?
 665          */
 666         if (!host->ocr) {
 667                 err = -EINVAL;
 668                 printk(KERN_WARNING  "mmc_valtage_support_error");
 669                 goto err;
 670         }
 671
 672         /*
 673          * Detect and init the card.
 674          */
 675         err = mmc_sd_init_card(host, host->ocr, NULL);
 676         if (err != MMC_ERR_NONE){
 677                 printk(KERN_WARNING  "mmc_sd_init_card error");
 678                 goto err;
 679         }
 680
 681         mmc_release_host(host);
 682
 683         err = mmc_add_card(host->card);
 684         if (err)
 685                 goto remove_card;
 686
 687         return 0;
 688
 689 remove_card:
 690         mmc_remove_card(host->card);
 691         host->card = NULL;
 692         mmc_claim_host(host);
 693 err:
 694         mmc_detach_bus(host);
 695         mmc_release_host(host);
 696
 697         printk(KERN_ERR "%s: error %d whilst initialising SD card\n",
 698                 mmc_hostname(host), err);
 699
 700         return 0;
 701 }
 702