drivers/mmc/core/sd.c

   1 /*
   2  *  linux/drivers/mmc/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
  19 #include "core.h"
  20 #include "sysfs.h"
  21 #include "mmc_ops.h"
  22 #include "sd_ops.h"
  23
  24 #include "core.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 static 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 void 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                 break;
 123         case 1:
 124                 /*
 125                  * This is a block-addressed SDHC card. Most
 126                  * interesting fields are unused and have fixed
 127                  * values. To avoid getting tripped by buggy cards,
 128                  * we assume those fixed values ourselves.
 129                  */
 130                 mmc_card_set_blockaddr(card);
 131
 132                 csd->tacc_ns     = 0; /* Unused */
 133                 csd->tacc_clks   = 0; /* Unused */
 134
 135                 m = UNSTUFF_BITS(resp, 99, 4);
 136                 e = UNSTUFF_BITS(resp, 96, 3);
 137                 csd->max_dtr      = tran_exp[e] * tran_mant[m];
 138                 csd->cmdclass     = UNSTUFF_BITS(resp, 84, 12);
 139
 140                 m = UNSTUFF_BITS(resp, 48, 22);
 141                 csd->capacity     = (1 + m) << 10;
 142
 143                 csd->read_blkbits = 9;
 144                 csd->read_partial = 0;
 145                 csd->write_misalign = 0;
 146                 csd->read_misalign = 0;
 147                 csd->r2w_factor = 4; /* Unused */
 148                 csd->write_blkbits = 9;
 149                 csd->write_partial = 0;
 150                 break;
 151         default:
 152                 printk("%s: unrecognised CSD structure version %d\n",
 153                         mmc_hostname(card->host), csd_struct);
 154                 mmc_card_set_bad(card);
 155                 return;
 156         }
 157 }
 158
 159 /*
 160  * Given a 64-bit response, decode to our card SCR structure.
 161  */
 162 static void mmc_decode_scr(struct mmc_card *card)
 163 {
 164         struct sd_scr *scr = &card->scr;
 165         unsigned int scr_struct;
 166         u32 resp[4];
 167
 168         BUG_ON(!mmc_card_sd(card));
 169
 170         resp[3] = card->raw_scr[1];
 171         resp[2] = card->raw_scr[0];
 172
 173         scr_struct = UNSTUFF_BITS(resp, 60, 4);
 174         if (scr_struct != 0) {
 175                 printk("%s: unrecognised SCR structure version %d\n",
 176                         mmc_hostname(card->host), scr_struct);
 177                 mmc_card_set_bad(card);
 178                 return;
 179         }
 180
 181         scr->sda_vsn = UNSTUFF_BITS(resp, 56, 4);
 182         scr->bus_widths = UNSTUFF_BITS(resp, 48, 4);
 183 }
 184
 185 /*
 186  * Fetches and decodes switch information
 187  */
 188 static int mmc_read_switch(struct mmc_card *card)
 189 {
 190         int err;
 191         u8 *status;
 192
 193         err = MMC_ERR_FAILED;
 194
 195         status = kmalloc(64, GFP_KERNEL);
 196         if (!status) {
 197                 printk("%s: could not allocate a buffer for switch "
 198                        "capabilities.\n",
 199                         mmc_hostname(card->host));
 200                 return err;
 201         }
 202
 203         err = mmc_sd_switch(card, 0, 0, 1, status);
 204         if (err != MMC_ERR_NONE) {
 205                 /*
 206                  * Card not supporting high-speed will ignore the
 207                  * command.
 208                  */
 209                 err = MMC_ERR_NONE;
 210                 goto out;
 211         }
 212
 213         if (status[13] & 0x02)
 214                 card->sw_caps.hs_max_dtr = 50000000;
 215
 216 out:
 217         kfree(status);
 218
 219         return err;
 220 }
 221
 222 /*
 223  * Test if the card supports high-speed mode and, if so, switch to it.
 224  */
 225 static int mmc_switch_hs(struct mmc_card *card)
 226 {
 227         int err;
 228         u8 *status;
 229
 230         if (!(card->host->caps & MMC_CAP_SD_HIGHSPEED))
 231                 return MMC_ERR_NONE;
 232
 233         if (card->sw_caps.hs_max_dtr == 0)
 234                 return MMC_ERR_NONE;
 235
 236         err = MMC_ERR_FAILED;
 237
 238         status = kmalloc(64, GFP_KERNEL);
 239         if (!status) {
 240                 printk("%s: could not allocate a buffer for switch "
 241                        "capabilities.\n",
 242                         mmc_hostname(card->host));
 243                 return err;
 244         }
 245
 246         err = mmc_sd_switch(card, 1, 0, 1, status);
 247         if (err != MMC_ERR_NONE)
 248                 goto out;
 249
 250         if ((status[16] & 0xF) != 1) {
 251                 printk(KERN_WARNING "%s: Problem switching card "
 252                         "into high-speed mode!\n",
 253                         mmc_hostname(card->host));
 254         } else {
 255                 mmc_card_set_highspeed(card);
 256                 mmc_set_timing(card->host, MMC_TIMING_SD_HS);
 257         }
 258
 259 out:
 260         kfree(status);
 261
 262         return err;
 263 }
 264
 265 /*
 266  * Handle the detection and initialisation of a card.
 267  *
 268  * In the case of a resume, "curcard" will contain the card
 269  * we're trying to reinitialise.
 270  */
 271 static int mmc_sd_init_card(struct mmc_host *host, u32 ocr,
 272         struct mmc_card *oldcard)
 273 {
 274         struct mmc_card *card;
 275         int err;
 276         u32 cid[4];
 277         unsigned int max_dtr;
 278
 279         BUG_ON(!host);
 280         BUG_ON(!host->claimed);
 281
 282         /*
 283          * Since we're changing the OCR value, we seem to
 284          * need to tell some cards to go back to the idle
 285          * state.  We wait 1ms to give cards time to
 286          * respond.
 287          */
 288         mmc_go_idle(host);
 289
 290         /*
 291          * If SD_SEND_IF_COND indicates an SD 2.0
 292          * compliant card and we should set bit 30
 293          * of the ocr to indicate that we can handle
 294          * block-addressed SDHC cards.
 295          */
 296         err = mmc_send_if_cond(host, ocr);
 297         if (err == MMC_ERR_NONE)
 298                 ocr |= 1 << 30;
 299
 300         err = mmc_send_app_op_cond(host, ocr, NULL);
 301         if (err != MMC_ERR_NONE)
 302                 goto err;
 303
 304         /*
 305          * Fetch CID from card.
 306          */
 307         err = mmc_all_send_cid(host, cid);
 308         if (err != MMC_ERR_NONE)
 309                 goto err;
 310
 311         if (oldcard) {
 312                 if (memcmp(cid, oldcard->raw_cid, sizeof(cid)) != 0)
 313                         goto err;
 314
 315                 card = oldcard;
 316         } else {
 317                 /*
 318                  * Allocate card structure.
 319                  */
 320                 card = mmc_alloc_card(host);
 321                 if (IS_ERR(card))
 322                         goto err;
 323
 324                 card->type = MMC_TYPE_SD;
 325                 memcpy(card->raw_cid, cid, sizeof(card->raw_cid));
 326         }
 327
 328         /*
 329          * Set card RCA.
 330          */
 331         err = mmc_send_relative_addr(host, &card->rca);
 332         if (err != MMC_ERR_NONE)
 333                 goto free_card;
 334
 335         mmc_set_bus_mode(host, MMC_BUSMODE_PUSHPULL);
 336
 337         if (!oldcard) {
 338                 /*
 339                  * Fetch CSD from card.
 340                  */
 341                 err = mmc_send_csd(card, card->raw_csd);
 342                 if (err != MMC_ERR_NONE)
 343                         goto free_card;
 344
 345                 mmc_decode_csd(card);
 346                 mmc_decode_cid(card);
 347         }
 348
 349         /*
 350          * Select card, as all following commands rely on that.
 351          */
 352         err = mmc_select_card(card);
 353         if (err != MMC_ERR_NONE)
 354                 goto free_card;
 355
 356         if (!oldcard) {
 357                 /*
 358                  * Fetch SCR from card.
 359                  */
 360                 err = mmc_app_send_scr(card, card->raw_scr);
 361                 if (err != MMC_ERR_NONE)
 362                         goto free_card;
 363
 364                 mmc_decode_scr(card);
 365
 366                 /*
 367                  * Fetch switch information from card.
 368                  */
 369                 err = mmc_read_switch(card);
 370                 if (err != MMC_ERR_NONE)
 371                         goto free_card;
 372         }
 373
 374         /*
 375          * Attempt to change to high-speed (if supported)
 376          */
 377         err = mmc_switch_hs(card);
 378         if (err != MMC_ERR_NONE)
 379                 goto free_card;
 380
 381         /*
 382          * Compute bus speed.
 383          */
 384         max_dtr = (unsigned int)-1;
 385
 386         if (mmc_card_highspeed(card)) {
 387                 if (max_dtr > card->sw_caps.hs_max_dtr)
 388                         max_dtr = card->sw_caps.hs_max_dtr;
 389         } else if (max_dtr > card->csd.max_dtr) {
 390                 max_dtr = card->csd.max_dtr;
 391         }
 392
 393         mmc_set_clock(host, max_dtr);
 394
 395         /*
 396          * Switch to wider bus (if supported).
 397          */
 398         if ((host->caps && MMC_CAP_4_BIT_DATA) &&
 399                 (card->scr.bus_widths & SD_SCR_BUS_WIDTH_4)) {
 400                 err = mmc_app_set_bus_width(card, MMC_BUS_WIDTH_4);
 401                 if (err != MMC_ERR_NONE)
 402                         goto free_card;
 403
 404                 mmc_set_bus_width(host, MMC_BUS_WIDTH_4);
 405         }
 406
 407         if (!oldcard)
 408                 host->card = card;
 409
 410         return MMC_ERR_NONE;
 411
 412 free_card:
 413         if (!oldcard)
 414                 mmc_remove_card(card);
 415 err:
 416
 417         return MMC_ERR_FAILED;
 418 }
 419
 420 /*
 421  * Host is being removed. Free up the current card.
 422  */
 423 static void mmc_sd_remove(struct mmc_host *host)
 424 {
 425         BUG_ON(!host);
 426         BUG_ON(!host->card);
 427
 428         mmc_remove_card(host->card);
 429         host->card = NULL;
 430 }
 431
 432 /*
 433  * Card detection callback from host.
 434  */
 435 static void mmc_sd_detect(struct mmc_host *host)
 436 {
 437         int err;
 438
 439         BUG_ON(!host);
 440         BUG_ON(!host->card);
 441
 442         mmc_claim_host(host);
 443
 444         /*
 445          * Just check if our card has been removed.
 446          */
 447         err = mmc_send_status(host->card, NULL);
 448
 449         mmc_release_host(host);
 450
 451         if (err != MMC_ERR_NONE) {
 452                 mmc_remove_card(host->card);
 453                 host->card = NULL;
 454
 455                 mmc_claim_host(host);
 456                 mmc_detach_bus(host);
 457                 mmc_release_host(host);
 458         }
 459 }
 460
 461 #ifdef CONFIG_MMC_UNSAFE_RESUME
 462
 463 /*
 464  * Suspend callback from host.
 465  */
 466 static void mmc_sd_suspend(struct mmc_host *host)
 467 {
 468         BUG_ON(!host);
 469         BUG_ON(!host->card);
 470
 471         mmc_claim_host(host);
 472         mmc_deselect_cards(host);
 473         host->card->state &= ~MMC_STATE_HIGHSPEED;
 474         mmc_release_host(host);
 475 }
 476
 477 /*
 478  * Resume callback from host.
 479  *
 480  * This function tries to determine if the same card is still present
 481  * and, if so, restore all state to it.
 482  */
 483 static void mmc_sd_resume(struct mmc_host *host)
 484 {
 485         int err;
 486
 487         BUG_ON(!host);
 488         BUG_ON(!host->card);
 489
 490         mmc_claim_host(host);
 491
 492         err = mmc_sd_init_card(host, host->ocr, host->card);
 493         if (err != MMC_ERR_NONE) {
 494                 mmc_remove_card(host->card);
 495                 host->card = NULL;
 496
 497                 mmc_detach_bus(host);
 498         }
 499
 500         mmc_release_host(host);
 501 }
 502
 503 #else
 504
 505 #define mmc_sd_suspend NULL
 506 #define mmc_sd_resume NULL
 507
 508 #endif
 509
 510 static const struct mmc_bus_ops mmc_sd_ops = {
 511         .remove = mmc_sd_remove,
 512         .detect = mmc_sd_detect,
 513         .suspend = mmc_sd_suspend,
 514         .resume = mmc_sd_resume,
 515 };
 516
 517 /*
 518  * Starting point for SD card init.
 519  */
 520 int mmc_attach_sd(struct mmc_host *host, u32 ocr)
 521 {
 522         int err;
 523
 524         BUG_ON(!host);
 525         BUG_ON(!host->claimed);
 526
 527         mmc_attach_bus(host, &mmc_sd_ops);
 528
 529         /*
 530          * Sanity check the voltages that the card claims to
 531          * support.
 532          */
 533         if (ocr & 0x7F) {
 534                 printk(KERN_WARNING "%s: card claims to support voltages "
 535                        "below the defined range. These will be ignored.\n",
 536                        mmc_hostname(host));
 537                 ocr &= ~0x7F;
 538         }
 539
 540         if (ocr & MMC_VDD_165_195) {
 541                 printk(KERN_WARNING "%s: SD card claims to support the "
 542                        "incompletely defined 'low voltage range'. This "
 543                        "will be ignored.\n", mmc_hostname(host));
 544                 ocr &= ~MMC_VDD_165_195;
 545         }
 546
 547         host->ocr = mmc_select_voltage(host, ocr);
 548
 549         /*
 550          * Can we support the voltage(s) of the card(s)?
 551          */
 552         if (!host->ocr)
 553                 goto err;
 554
 555         /*
 556          * Detect and init the card.
 557          */
 558         err = mmc_sd_init_card(host, host->ocr, NULL);
 559         if (err != MMC_ERR_NONE)
 560                 goto err;
 561
 562         mmc_release_host(host);
 563
 564         err = mmc_register_card(host->card);
 565         if (err)
 566                 goto reclaim_host;
 567
 568         return 0;
 569
 570 reclaim_host:
 571         mmc_claim_host(host);
 572         mmc_remove_card(host->card);
 573         host->card = NULL;
 574 err:
 575         mmc_detach_bus(host);
 576         mmc_release_host(host);
 577
 578         return 0;
 579 }
 580