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 #include <linux/slab.h>
  15
  16 #include <linux/mmc/host.h>
  17 #include <linux/mmc/card.h>
  18 #include <linux/mmc/mmc.h>
  19 #include <linux/mmc/sd.h>
  20
  21 #include "core.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 #define UNSTUFF_BITS(resp,start,size)                                   \
  46         ({                                                              \
  47                 const int __size = size;                                \
  48                 const u32 __mask = (__size < 32 ? 1 << __size : 0) - 1; \
  49                 const int __off = 3 - ((start) / 32);                   \
  50                 const int __shft = (start) & 31;                        \
  51                 u32 __res;                                              \
  52                                                                         \
  53                 __res = resp[__off] >> __shft;                          \
  54                 if (__size + __shft > 32)                               \
  55                         __res |= resp[__off-1] << ((32 - __shft) % 32); \
  56                 __res & __mask;                                         \
  57         })
  58
  59 /*
  60  * Given the decoded CSD structure, decode the raw CID to our CID structure.
  61  */
  62 void mmc_decode_cid(struct mmc_card *card)
  63 {
  64         u32 *resp = card->raw_cid;
  65
  66         memset(&card->cid, 0, sizeof(struct mmc_cid));
  67
  68         /*
  69          * SD doesn't currently have a version field so we will
  70          * have to assume we can parse this.
  71          */
  72         card->cid.manfid                = UNSTUFF_BITS(resp, 120, 8);
  73         card->cid.oemid                 = UNSTUFF_BITS(resp, 104, 16);
  74         card->cid.prod_name[0]          = UNSTUFF_BITS(resp, 96, 8);
  75         card->cid.prod_name[1]          = UNSTUFF_BITS(resp, 88, 8);
  76         card->cid.prod_name[2]          = UNSTUFF_BITS(resp, 80, 8);
  77         card->cid.prod_name[3]          = UNSTUFF_BITS(resp, 72, 8);
  78         card->cid.prod_name[4]          = UNSTUFF_BITS(resp, 64, 8);
  79         card->cid.hwrev                 = UNSTUFF_BITS(resp, 60, 4);
  80         card->cid.fwrev                 = UNSTUFF_BITS(resp, 56, 4);
  81         card->cid.serial                = UNSTUFF_BITS(resp, 24, 32);
  82         card->cid.year                  = UNSTUFF_BITS(resp, 12, 8);
  83         card->cid.month                 = UNSTUFF_BITS(resp, 8, 4);
  84
  85         card->cid.year += 2000; /* SD cards year offset */
  86 }
  87
  88 /*
  89  * Given a 128-bit response, decode to our card CSD structure.
  90  */
  91 static int mmc_decode_csd(struct mmc_card *card)
  92 {
  93         struct mmc_csd *csd = &card->csd;
  94         unsigned int e, m, csd_struct;
  95         u32 *resp = card->raw_csd;
  96
  97         csd_struct = UNSTUFF_BITS(resp, 126, 2);
  98
  99         switch (csd_struct) {
 100         case 0:
 101                 m = UNSTUFF_BITS(resp, 115, 4);
 102                 e = UNSTUFF_BITS(resp, 112, 3);
 103                 csd->tacc_ns     = (tacc_exp[e] * tacc_mant[m] + 9) / 10;
 104                 csd->tacc_clks   = UNSTUFF_BITS(resp, 104, 8) * 100;
 105
 106                 m = UNSTUFF_BITS(resp, 99, 4);
 107                 e = UNSTUFF_BITS(resp, 96, 3);
 108                 csd->max_dtr      = tran_exp[e] * tran_mant[m];
 109                 csd->cmdclass     = UNSTUFF_BITS(resp, 84, 12);
 110
 111                 e = UNSTUFF_BITS(resp, 47, 3);
 112                 m = UNSTUFF_BITS(resp, 62, 12);
 113                 csd->capacity     = (1 + m) << (e + 2);
 114
 115                 csd->read_blkbits = UNSTUFF_BITS(resp, 80, 4);
 116                 csd->read_partial = UNSTUFF_BITS(resp, 79, 1);
 117                 csd->write_misalign = UNSTUFF_BITS(resp, 78, 1);
 118                 csd->read_misalign = UNSTUFF_BITS(resp, 77, 1);
 119                 csd->r2w_factor = UNSTUFF_BITS(resp, 26, 3);
 120                 csd->write_blkbits = UNSTUFF_BITS(resp, 22, 4);
 121                 csd->write_partial = UNSTUFF_BITS(resp, 21, 1);
 122
 123                 if (UNSTUFF_BITS(resp, 46, 1)) {
 124                         csd->erase_size = 1;
 125                 } else if (csd->write_blkbits >= 9) {
 126                         csd->erase_size = UNSTUFF_BITS(resp, 39, 7) + 1;
 127                         csd->erase_size <<= csd->write_blkbits - 9;
 128                 }
 129                 break;
 130         case 1:
 131                 /*
 132                  * This is a block-addressed SDHC card. Most
 133                  * interesting fields are unused and have fixed
 134                  * values. To avoid getting tripped by buggy cards,
 135                  * we assume those fixed values ourselves.
 136                  */
 137                 mmc_card_set_blockaddr(card);
 138
 139                 csd->tacc_ns     = 0; /* Unused */
 140                 csd->tacc_clks   = 0; /* Unused */
 141
 142                 m = UNSTUFF_BITS(resp, 99, 4);
 143                 e = UNSTUFF_BITS(resp, 96, 3);
 144                 csd->max_dtr      = tran_exp[e] * tran_mant[m];
 145                 csd->cmdclass     = UNSTUFF_BITS(resp, 84, 12);
 146
 147                 m = UNSTUFF_BITS(resp, 48, 22);
 148                 csd->capacity     = (1 + m) << 10;
 149
 150                 csd->read_blkbits = 9;
 151                 csd->read_partial = 0;
 152                 csd->write_misalign = 0;
 153                 csd->read_misalign = 0;
 154                 csd->r2w_factor = 4; /* Unused */
 155                 csd->write_blkbits = 9;
 156                 csd->write_partial = 0;
 157                 csd->erase_size = 1;
 158                 break;
 159         default:
 160                 printk(KERN_ERR "%s: unrecognised CSD structure version %d\n",
 161                         mmc_hostname(card->host), csd_struct);
 162                 return -EINVAL;
 163         }
 164
 165         card->erase_size = csd->erase_size;
 166
 167         return 0;
 168 }
 169
 170 /*
 171  * Given a 64-bit response, decode to our card SCR structure.
 172  */
 173 static int mmc_decode_scr(struct mmc_card *card)
 174 {
 175         struct sd_scr *scr = &card->scr;
 176         unsigned int scr_struct;
 177         u32 resp[4];
 178
 179         resp[3] = card->raw_scr[1];
 180         resp[2] = card->raw_scr[0];
 181
 182         scr_struct = UNSTUFF_BITS(resp, 60, 4);
 183         if (scr_struct != 0) {
 184                 printk(KERN_ERR "%s: unrecognised SCR structure version %d\n",
 185                         mmc_hostname(card->host), scr_struct);
 186                 return -EINVAL;
 187         }
 188
 189         scr->sda_vsn = UNSTUFF_BITS(resp, 56, 4);
 190         scr->bus_widths = UNSTUFF_BITS(resp, 48, 4);
 191
 192         if (UNSTUFF_BITS(resp, 55, 1))
 193                 card->erased_byte = 0xFF;
 194         else
 195                 card->erased_byte = 0x0;
 196
 197         return 0;
 198 }
 199
 200 /*
 201  * Fetch and process SD Status register.
 202  */
 203 static int mmc_read_ssr(struct mmc_card *card)
 204 {
 205         unsigned int au, es, et, eo;
 206         int err, i;
 207         u32 *ssr;
 208
 209         if (!(card->csd.cmdclass & CCC_APP_SPEC)) {
 210                 printk(KERN_WARNING "%s: card lacks mandatory SD Status "
 211                         "function.\n", mmc_hostname(card->host));
 212                 return 0;
 213         }
 214
 215         ssr = kmalloc(64, GFP_KERNEL);
 216         if (!ssr)
 217                 return -ENOMEM;
 218
 219         err = mmc_app_sd_status(card, ssr);
 220         if (err) {
 221                 printk(KERN_WARNING "%s: problem reading SD Status "
 222                         "register.\n", mmc_hostname(card->host));
 223                 err = 0;
 224                 goto out;
 225         }
 226
 227         for (i = 0; i < 16; i++)
 228                 ssr[i] = be32_to_cpu(ssr[i]);
 229
 230         /*
 231          * UNSTUFF_BITS only works with four u32s so we have to offset the
 232          * bitfield positions accordingly.
 233          */
 234         au = UNSTUFF_BITS(ssr, 428 - 384, 4);
 235         if (au > 0 || au <= 9) {
 236                 card->ssr.au = 1 << (au + 4);
 237                 es = UNSTUFF_BITS(ssr, 408 - 384, 16);
 238                 et = UNSTUFF_BITS(ssr, 402 - 384, 6);
 239                 eo = UNSTUFF_BITS(ssr, 400 - 384, 2);
 240                 if (es && et) {
 241                         card->ssr.erase_timeout = (et * 1000) / es;
 242                         card->ssr.erase_offset = eo * 1000;
 243                 }
 244         } else {
 245                 printk(KERN_WARNING "%s: SD Status: Invalid Allocation Unit "
 246                         "size.\n", mmc_hostname(card->host));
 247         }
 248 out:
 249         kfree(ssr);
 250         return err;
 251 }
 252
 253 /*
 254  * Fetches and decodes switch information
 255  */
 256 static int mmc_read_switch(struct mmc_card *card)
 257 {
 258         int err;
 259         u8 *status;
 260
 261         if (card->scr.sda_vsn < SCR_SPEC_VER_1)
 262                 return 0;
 263
 264         if (!(card->csd.cmdclass & CCC_SWITCH)) {
 265                 printk(KERN_WARNING "%s: card lacks mandatory switch "
 266                         "function, performance might suffer.\n",
 267                         mmc_hostname(card->host));
 268                 return 0;
 269         }
 270
 271         err = -EIO;
 272
 273         status = kmalloc(64, GFP_KERNEL);
 274         if (!status) {
 275                 printk(KERN_ERR "%s: could not allocate a buffer for "
 276                         "switch capabilities.\n", mmc_hostname(card->host));
 277                 return -ENOMEM;
 278         }
 279
 280         err = mmc_sd_switch(card, 0, 0, 1, status);
 281         if (err) {
 282                 /* If the host or the card can't do the switch,
 283                  * fail more gracefully. */
 284                 if ((err != -EINVAL)
 285                  && (err != -ENOSYS)
 286                  && (err != -EFAULT))
 287                         goto out;
 288
 289                 printk(KERN_WARNING "%s: problem reading switch "
 290                         "capabilities, performance might suffer.\n",
 291                         mmc_hostname(card->host));
 292                 err = 0;
 293
 294                 goto out;
 295         }
 296
 297         if (status[13] & 0x02)
 298                 card->sw_caps.hs_max_dtr = 50000000;
 299
 300 out:
 301         kfree(status);
 302
 303         return err;
 304 }
 305
 306 /*
 307  * Test if the card supports high-speed mode and, if so, switch to it.
 308  */
 309 int mmc_sd_switch_hs(struct mmc_card *card)
 310 {
 311         int err;
 312         u8 *status;
 313
 314         if (card->scr.sda_vsn < SCR_SPEC_VER_1)
 315                 return 0;
 316
 317         if (!(card->csd.cmdclass & CCC_SWITCH))
 318                 return 0;
 319
 320         if (!(card->host->caps & MMC_CAP_SD_HIGHSPEED))
 321                 return 0;
 322
 323         if (card->sw_caps.hs_max_dtr == 0)
 324                 return 0;
 325
 326         err = -EIO;
 327
 328         status = kmalloc(64, GFP_KERNEL);
 329         if (!status) {
 330                 printk(KERN_ERR "%s: could not allocate a buffer for "
 331                         "switch capabilities.\n", mmc_hostname(card->host));
 332                 return -ENOMEM;
 333         }
 334
 335         err = mmc_sd_switch(card, 1, 0, 1, status);
 336         if (err)
 337                 goto out;
 338
 339         if ((status[16] & 0xF) != 1) {
 340                 printk(KERN_WARNING "%s: Problem switching card "
 341                         "into high-speed mode!\n",
 342                         mmc_hostname(card->host));
 343                 err = 0;
 344         } else {
 345                 err = 1;
 346         }
 347
 348 out:
 349         kfree(status);
 350
 351         return err;
 352 }
 353
 354 MMC_DEV_ATTR(cid, "%08x%08x%08x%08x\n", card->raw_cid[0], card->raw_cid[1],
 355         card->raw_cid[2], card->raw_cid[3]);
 356 MMC_DEV_ATTR(csd, "%08x%08x%08x%08x\n", card->raw_csd[0], card->raw_csd[1],
 357         card->raw_csd[2], card->raw_csd[3]);
 358 MMC_DEV_ATTR(scr, "%08x%08x\n", card->raw_scr[0], card->raw_scr[1]);
 359 MMC_DEV_ATTR(date, "%02d/%04d\n", card->cid.month, card->cid.year);
 360 MMC_DEV_ATTR(erase_size, "%u\n", card->erase_size << 9);
 361 MMC_DEV_ATTR(preferred_erase_size, "%u\n", card->pref_erase << 9);
 362 MMC_DEV_ATTR(fwrev, "0x%x\n", card->cid.fwrev);
 363 MMC_DEV_ATTR(hwrev, "0x%x\n", card->cid.hwrev);
 364 MMC_DEV_ATTR(manfid, "0x%06x\n", card->cid.manfid);
 365 MMC_DEV_ATTR(name, "%s\n", card->cid.prod_name);
 366 MMC_DEV_ATTR(oemid, "0x%04x\n", card->cid.oemid);
 367 MMC_DEV_ATTR(serial, "0x%08x\n", card->cid.serial);
 368
 369
 370 static struct attribute *sd_std_attrs[] = {
 371         &dev_attr_cid.attr,
 372         &dev_attr_csd.attr,
 373         &dev_attr_scr.attr,
 374         &dev_attr_date.attr,
 375         &dev_attr_erase_size.attr,
 376         &dev_attr_preferred_erase_size.attr,
 377         &dev_attr_fwrev.attr,
 378         &dev_attr_hwrev.attr,
 379         &dev_attr_manfid.attr,
 380         &dev_attr_name.attr,
 381         &dev_attr_oemid.attr,
 382         &dev_attr_serial.attr,
 383         NULL,
 384 };
 385
 386 static struct attribute_group sd_std_attr_group = {
 387         .attrs = sd_std_attrs,
 388 };
 389
 390 static const struct attribute_group *sd_attr_groups[] = {
 391         &sd_std_attr_group,
 392         NULL,
 393 };
 394
 395 struct device_type sd_type = {
 396         .groups = sd_attr_groups,
 397 };
 398
 399 /*
 400  * Fetch CID from card.
 401  */
 402 int mmc_sd_get_cid(struct mmc_host *host, u32 ocr, u32 *cid)
 403 {
 404         int err;
 405
 406         /*
 407          * Since we're changing the OCR value, we seem to
 408          * need to tell some cards to go back to the idle
 409          * state.  We wait 1ms to give cards time to
 410          * respond.
 411          */
 412         mmc_go_idle(host);
 413
 414         /*
 415          * If SD_SEND_IF_COND indicates an SD 2.0
 416          * compliant card and we should set bit 30
 417          * of the ocr to indicate that we can handle
 418          * block-addressed SDHC cards.
 419          */
 420         err = mmc_send_if_cond(host, ocr);
 421         if (!err)
 422                 ocr |= 1 << 30;
 423
 424         err = mmc_send_app_op_cond(host, ocr, NULL);
 425         if (err)
 426                 return err;
 427
 428         if (mmc_host_is_spi(host))
 429                 err = mmc_send_cid(host, cid);
 430         else
 431                 err = mmc_all_send_cid(host, cid);
 432
 433         return err;
 434 }
 435
 436 int mmc_sd_get_csd(struct mmc_host *host, struct mmc_card *card)
 437 {
 438         int err;
 439
 440         /*
 441          * Fetch CSD from card.
 442          */
 443         err = mmc_send_csd(card, card->raw_csd);
 444         if (err)
 445                 return err;
 446
 447         err = mmc_decode_csd(card);
 448         if (err)
 449                 return err;
 450
 451         return 0;
 452 }
 453
 454 int mmc_sd_setup_card(struct mmc_host *host, struct mmc_card *card,
 455         bool reinit)
 456 {
 457         int err;
 458
 459         if (!reinit) {
 460                 /*
 461                  * Fetch SCR from card.
 462                  */
 463                 err = mmc_app_send_scr(card, card->raw_scr);
 464                 if (err)
 465                         return err;
 466
 467                 err = mmc_decode_scr(card);
 468                 if (err)
 469                         return err;
 470
 471                 /*
 472                  * Fetch and process SD Status register.
 473                  */
 474                 err = mmc_read_ssr(card);
 475                 if (err)
 476                         return err;
 477
 478                 /* Erase init depends on CSD and SSR */
 479                 mmc_init_erase(card);
 480
 481                 /*
 482                  * Fetch switch information from card.
 483                  */
 484                 err = mmc_read_switch(card);
 485                 if (err)
 486                         return err;
 487         }
 488
 489         /*
 490          * For SPI, enable CRC as appropriate.
 491          * This CRC enable is located AFTER the reading of the
 492          * card registers because some SDHC cards are not able
 493          * to provide valid CRCs for non-512-byte blocks.
 494          */
 495         if (mmc_host_is_spi(host)) {
 496                 err = mmc_spi_set_crc(host, use_spi_crc);
 497                 if (err)
 498                         return err;
 499         }
 500
 501         /*
 502          * Check if read-only switch is active.
 503          */
 504         if (!reinit) {
 505                 int ro = -1;
 506
 507                 if (host->ops->get_ro)
 508                         ro = host->ops->get_ro(host);
 509
 510                 if (ro < 0) {
 511                         printk(KERN_WARNING "%s: host does not "
 512                                 "support reading read-only "
 513                                 "switch. assuming write-enable.\n",
 514                                 mmc_hostname(host));
 515                 } else if (ro > 0) {
 516                         mmc_card_set_readonly(card);
 517                 }
 518         }
 519
 520         return 0;
 521 }
 522
 523 unsigned mmc_sd_get_max_clock(struct mmc_card *card)
 524 {
 525         unsigned max_dtr = (unsigned int)-1;
 526
 527         if (mmc_card_highspeed(card)) {
 528                 if (max_dtr > card->sw_caps.hs_max_dtr)
 529                         max_dtr = card->sw_caps.hs_max_dtr;
 530         } else if (max_dtr > card->csd.max_dtr) {
 531                 max_dtr = card->csd.max_dtr;
 532         }
 533
 534         return max_dtr;
 535 }
 536
 537 void mmc_sd_go_highspeed(struct mmc_card *card)
 538 {
 539         mmc_card_set_highspeed(card);
 540         mmc_set_timing(card->host, MMC_TIMING_SD_HS);
 541 }
 542
 543 /*
 544  * Handle the detection and initialisation of a card.
 545  *
 546  * In the case of a resume, "oldcard" will contain the card
 547  * we're trying to reinitialise.
 548  */
 549 static int mmc_sd_init_card(struct mmc_host *host, u32 ocr,
 550         struct mmc_card *oldcard)
 551 {
 552         struct mmc_card *card;
 553         int err;
 554         u32 cid[4];
 555
 556         BUG_ON(!host);
 557         WARN_ON(!host->claimed);
 558
 559         err = mmc_sd_get_cid(host, ocr, cid);
 560         if (err)
 561                 return err;
 562
 563         if (oldcard) {
 564                 if (memcmp(cid, oldcard->raw_cid, sizeof(cid)) != 0)
 565                         return -ENOENT;
 566
 567                 card = oldcard;
 568         } else {
 569                 /*
 570                  * Allocate card structure.
 571                  */
 572                 card = mmc_alloc_card(host, &sd_type);
 573                 if (IS_ERR(card))
 574                         return PTR_ERR(card);
 575
 576                 card->type = MMC_TYPE_SD;
 577                 memcpy(card->raw_cid, cid, sizeof(card->raw_cid));
 578         }
 579
 580         /*
 581          * For native busses:  get card RCA and quit open drain mode.
 582          */
 583         if (!mmc_host_is_spi(host)) {
 584                 err = mmc_send_relative_addr(host, &card->rca);
 585                 if (err)
 586                         return err;
 587
 588                 mmc_set_bus_mode(host, MMC_BUSMODE_PUSHPULL);
 589         }
 590
 591         if (!oldcard) {
 592                 err = mmc_sd_get_csd(host, card);
 593                 if (err)
 594                         return err;
 595
 596                 mmc_decode_cid(card);
 597         }
 598
 599         /*
 600          * Select card, as all following commands rely on that.
 601          */
 602         if (!mmc_host_is_spi(host)) {
 603                 err = mmc_select_card(card);
 604                 if (err)
 605                         return err;
 606         }
 607
 608         err = mmc_sd_setup_card(host, card, oldcard != NULL);
 609         if (err)
 610                 goto free_card;
 611
 612         /*
 613          * Attempt to change to high-speed (if supported)
 614          */
 615         err = mmc_sd_switch_hs(card);
 616         if (err > 0)
 617                 mmc_sd_go_highspeed(card);
 618         else if (err)
 619                 goto free_card;
 620
 621         /*
 622          * Set bus speed.
 623          */
 624         mmc_set_clock(host, mmc_sd_get_max_clock(card));
 625
 626         /*
 627          * Switch to wider bus (if supported).
 628          */
 629         if ((host->caps & MMC_CAP_4_BIT_DATA) &&
 630                 (card->scr.bus_widths & SD_SCR_BUS_WIDTH_4)) {
 631                 err = mmc_app_set_bus_width(card, MMC_BUS_WIDTH_4);
 632                 if (err)
 633                         goto free_card;
 634
 635                 mmc_set_bus_width(host, MMC_BUS_WIDTH_4);
 636         }
 637
 638         host->card = card;
 639         return 0;
 640
 641 free_card:
 642         if (!oldcard)
 643                 mmc_remove_card(card);
 644
 645         return err;
 646 }
 647
 648 /*
 649  * Host is being removed. Free up the current card.
 650  */
 651 static void mmc_sd_remove(struct mmc_host *host)
 652 {
 653         BUG_ON(!host);
 654         BUG_ON(!host->card);
 655
 656         mmc_remove_card(host->card);
 657         host->card = NULL;
 658 }
 659
 660 /*
 661  * Card detection callback from host.
 662  */
 663 static void mmc_sd_detect(struct mmc_host *host)
 664 {
 665         int err;
 666
 667         BUG_ON(!host);
 668         BUG_ON(!host->card);
 669
 670         mmc_claim_host(host);
 671
 672         /*
 673          * Just check if our card has been removed.
 674          */
 675         err = mmc_send_status(host->card, NULL);
 676
 677         mmc_release_host(host);
 678
 679         if (err) {
 680                 mmc_sd_remove(host);
 681
 682                 mmc_claim_host(host);
 683                 mmc_detach_bus(host);
 684                 mmc_release_host(host);
 685         }
 686 }
 687
 688 /*
 689  * Suspend callback from host.
 690  */
 691 static int mmc_sd_suspend(struct mmc_host *host)
 692 {
 693         BUG_ON(!host);
 694         BUG_ON(!host->card);
 695
 696         mmc_claim_host(host);
 697         if (!mmc_host_is_spi(host))
 698                 mmc_deselect_cards(host);
 699         host->card->state &= ~MMC_STATE_HIGHSPEED;
 700         mmc_release_host(host);
 701
 702         return 0;
 703 }
 704
 705 /*
 706  * Resume callback from host.
 707  *
 708  * This function tries to determine if the same card is still present
 709  * and, if so, restore all state to it.
 710  */
 711 static int mmc_sd_resume(struct mmc_host *host)
 712 {
 713         int err;
 714
 715         BUG_ON(!host);
 716         BUG_ON(!host->card);
 717
 718         mmc_claim_host(host);
 719         err = mmc_sd_init_card(host, host->ocr, host->card);
 720         mmc_release_host(host);
 721
 722         return err;
 723 }
 724
 725 static int mmc_sd_power_restore(struct mmc_host *host)
 726 {
 727         int ret;
 728
 729         host->card->state &= ~MMC_STATE_HIGHSPEED;
 730         mmc_claim_host(host);
 731         ret = mmc_sd_init_card(host, host->ocr, host->card);
 732         mmc_release_host(host);
 733
 734         return ret;
 735 }
 736
 737 static const struct mmc_bus_ops mmc_sd_ops = {
 738         .remove = mmc_sd_remove,
 739         .detect = mmc_sd_detect,
 740         .suspend = NULL,
 741         .resume = NULL,
 742         .power_restore = mmc_sd_power_restore,
 743 };
 744
 745 static const struct mmc_bus_ops mmc_sd_ops_unsafe = {
 746         .remove = mmc_sd_remove,
 747         .detect = mmc_sd_detect,
 748         .suspend = mmc_sd_suspend,
 749         .resume = mmc_sd_resume,
 750         .power_restore = mmc_sd_power_restore,
 751 };
 752
 753 static void mmc_sd_attach_bus_ops(struct mmc_host *host)
 754 {
 755         const struct mmc_bus_ops *bus_ops;
 756
 757         if (!mmc_card_is_removable(host))
 758                 bus_ops = &mmc_sd_ops_unsafe;
 759         else
 760                 bus_ops = &mmc_sd_ops;
 761         mmc_attach_bus(host, bus_ops);
 762 }
 763
 764 /*
 765  * Starting point for SD card init.
 766  */
 767 int mmc_attach_sd(struct mmc_host *host)
 768 {
 769         int err;
 770         u32 ocr;
 771
 772         BUG_ON(!host);
 773         WARN_ON(!host->claimed);
 774
 775         err = mmc_send_app_op_cond(host, 0, &ocr);
 776         if (err)
 777                 return err;
 778
 779         mmc_sd_attach_bus_ops(host);
 780         if (host->ocr_avail_sd)
 781                 host->ocr_avail = host->ocr_avail_sd;
 782
 783         /*
 784          * We need to get OCR a different way for SPI.
 785          */
 786         if (mmc_host_is_spi(host)) {
 787                 mmc_go_idle(host);
 788
 789                 err = mmc_spi_read_ocr(host, 0, &ocr);
 790                 if (err)
 791                         goto err;
 792         }
 793
 794         /*
 795          * Sanity check the voltages that the card claims to
 796          * support.
 797          */
 798         if (ocr & 0x7F) {
 799                 printk(KERN_WARNING "%s: card claims to support voltages "
 800                        "below the defined range. These will be ignored.\n",
 801                        mmc_hostname(host));
 802                 ocr &= ~0x7F;
 803         }
 804
 805         if ((ocr & MMC_VDD_165_195) &&
 806             !(host->ocr_avail_sd & MMC_VDD_165_195)) {
 807                 printk(KERN_WARNING "%s: SD card claims to support the "
 808                        "incompletely defined 'low voltage range'. This "
 809                        "will be ignored.\n", mmc_hostname(host));
 810                 ocr &= ~MMC_VDD_165_195;
 811         }
 812
 813         host->ocr = mmc_select_voltage(host, ocr);
 814
 815         /*
 816          * Can we support the voltage(s) of the card(s)?
 817          */
 818         if (!host->ocr) {
 819                 err = -EINVAL;
 820                 goto err;
 821         }
 822
 823         /*
 824          * Detect and init the card.
 825          */
 826         err = mmc_sd_init_card(host, host->ocr, NULL);
 827         if (err)
 828                 goto err;
 829
 830         mmc_release_host(host);
 831         err = mmc_add_card(host->card);
 832         mmc_claim_host(host);
 833         if (err)
 834                 goto remove_card;
 835
 836         return 0;
 837
 838 remove_card:
 839         mmc_release_host(host);
 840         mmc_remove_card(host->card);
 841         host->card = NULL;
 842         mmc_claim_host(host);
 843 err:
 844         mmc_detach_bus(host);
 845
 846         printk(KERN_ERR "%s: error %d whilst initialising SD card\n",
 847                 mmc_hostname(host), err);
 848
 849         return err;
 850 }
 851