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 #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 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 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(KERN_ERR "%s: unrecognised CSD structure version %d\n", 153 mmc_hostname(card->host), csd_struct); 154 return -EINVAL; 155 } 156 157 return 0; 158 } 159 160 /* 161 * Given a 64-bit response, decode to our card SCR structure. 162 */ 163 static int mmc_decode_scr(struct mmc_card *card) 164 { 165 struct sd_scr *scr = &card->scr; 166 unsigned int scr_struct; 167 u32 resp[4]; 168 169 BUG_ON(!mmc_card_sd(card)); 170 171 resp[3] = card->raw_scr[1]; 172 resp[2] = card->raw_scr[0]; 173 174 scr_struct = UNSTUFF_BITS(resp, 60, 4); 175 if (scr_struct != 0) { 176 printk(KERN_ERR "%s: unrecognised SCR structure version %d\n", 177 mmc_hostname(card->host), scr_struct); 178 return -EINVAL; 179 } 180 181 scr->sda_vsn = UNSTUFF_BITS(resp, 56, 4); 182 scr->bus_widths = UNSTUFF_BITS(resp, 48, 4); 183 184 return 0; 185 } 186 187 /* 188 * Fetches and decodes switch information 189 */ 190 static int mmc_read_switch(struct mmc_card *card) 191 { 192 int err; 193 u8 *status; 194 195 if (card->scr.sda_vsn < SCR_SPEC_VER_1) 196 return MMC_ERR_NONE; 197 198 if (!(card->csd.cmdclass & CCC_SWITCH)) { 199 printk(KERN_WARNING "%s: card lacks mandatory switch " 200 "function, performance might suffer.\n", 201 mmc_hostname(card->host)); 202 return MMC_ERR_NONE; 203 } 204 205 err = MMC_ERR_FAILED; 206 207 status = kmalloc(64, GFP_KERNEL); 208 if (!status) { 209 printk(KERN_ERR "%s: could not allocate a buffer for " 210 "switch capabilities.\n", mmc_hostname(card->host)); 211 return err; 212 } 213 214 err = mmc_sd_switch(card, 0, 0, 1, status); 215 if (err != MMC_ERR_NONE) { 216 printk(KERN_WARNING "%s: problem reading switch " 217 "capabilities, performance might suffer.\n", 218 mmc_hostname(card->host)); 219 err = MMC_ERR_NONE; 220 goto out; 221 } 222 223 if (status[13] & 0x02) 224 card->sw_caps.hs_max_dtr = 50000000; 225 226 out: 227 kfree(status); 228 229 return err; 230 } 231 232 /* 233 * Test if the card supports high-speed mode and, if so, switch to it. 234 */ 235 static int mmc_switch_hs(struct mmc_card *card) 236 { 237 int err; 238 u8 *status; 239 240 if (card->scr.sda_vsn < SCR_SPEC_VER_1) 241 return MMC_ERR_NONE; 242 243 if (!(card->csd.cmdclass & CCC_SWITCH)) 244 return MMC_ERR_NONE; 245 246 if (!(card->host->caps & MMC_CAP_SD_HIGHSPEED)) 247 return MMC_ERR_NONE; 248 249 if (card->sw_caps.hs_max_dtr == 0) 250 return MMC_ERR_NONE; 251 252 err = MMC_ERR_FAILED; 253 254 status = kmalloc(64, GFP_KERNEL); 255 if (!status) { 256 printk(KERN_ERR "%s: could not allocate a buffer for " 257 "switch capabilities.\n", mmc_hostname(card->host)); 258 return err; 259 } 260 261 err = mmc_sd_switch(card, 1, 0, 1, status); 262 if (err != MMC_ERR_NONE) 263 goto out; 264 265 if ((status[16] & 0xF) != 1) { 266 printk(KERN_WARNING "%s: Problem switching card " 267 "into high-speed mode!\n", 268 mmc_hostname(card->host)); 269 } else { 270 mmc_card_set_highspeed(card); 271 mmc_set_timing(card->host, MMC_TIMING_SD_HS); 272 } 273 274 out: 275 kfree(status); 276 277 return err; 278 } 279 280 /* 281 * Handle the detection and initialisation of a card. 282 * 283 * In the case of a resume, "curcard" will contain the card 284 * we're trying to reinitialise. 285 */ 286 static int mmc_sd_init_card(struct mmc_host *host, u32 ocr, 287 struct mmc_card *oldcard) 288 { 289 struct mmc_card *card; 290 int err; 291 u32 cid[4]; 292 unsigned int max_dtr; 293 294 BUG_ON(!host); 295 BUG_ON(!host->claimed); 296 297 /* 298 * Since we're changing the OCR value, we seem to 299 * need to tell some cards to go back to the idle 300 * state. We wait 1ms to give cards time to 301 * respond. 302 */ 303 mmc_go_idle(host); 304 305 /* 306 * If SD_SEND_IF_COND indicates an SD 2.0 307 * compliant card and we should set bit 30 308 * of the ocr to indicate that we can handle 309 * block-addressed SDHC cards. 310 */ 311 err = mmc_send_if_cond(host, ocr); 312 if (err == MMC_ERR_NONE) 313 ocr |= 1 << 30; 314 315 err = mmc_send_app_op_cond(host, ocr, NULL); 316 if (err != MMC_ERR_NONE) 317 goto err; 318 319 /* 320 * Fetch CID from card. 321 */ 322 err = mmc_all_send_cid(host, cid); 323 if (err != MMC_ERR_NONE) 324 goto err; 325 326 if (oldcard) { 327 if (memcmp(cid, oldcard->raw_cid, sizeof(cid)) != 0) 328 goto err; 329 330 card = oldcard; 331 } else { 332 /* 333 * Allocate card structure. 334 */ 335 card = mmc_alloc_card(host); 336 if (IS_ERR(card)) 337 goto err; 338 339 card->type = MMC_TYPE_SD; 340 memcpy(card->raw_cid, cid, sizeof(card->raw_cid)); 341 } 342 343 /* 344 * Set card RCA. 345 */ 346 err = mmc_send_relative_addr(host, &card->rca); 347 if (err != MMC_ERR_NONE) 348 goto free_card; 349 350 mmc_set_bus_mode(host, MMC_BUSMODE_PUSHPULL); 351 352 if (!oldcard) { 353 /* 354 * Fetch CSD from card. 355 */ 356 err = mmc_send_csd(card, card->raw_csd); 357 if (err != MMC_ERR_NONE) 358 goto free_card; 359 360 err = mmc_decode_csd(card); 361 if (err < 0) 362 goto free_card; 363 364 mmc_decode_cid(card); 365 } 366 367 /* 368 * Select card, as all following commands rely on that. 369 */ 370 err = mmc_select_card(card); 371 if (err != MMC_ERR_NONE) 372 goto free_card; 373 374 if (!oldcard) { 375 /* 376 * Fetch SCR from card. 377 */ 378 err = mmc_app_send_scr(card, card->raw_scr); 379 if (err != MMC_ERR_NONE) 380 goto free_card; 381 382 err = mmc_decode_scr(card); 383 if (err < 0) 384 goto free_card; 385 386 /* 387 * Fetch switch information from card. 388 */ 389 err = mmc_read_switch(card); 390 if (err != MMC_ERR_NONE) 391 goto free_card; 392 } 393 394 /* 395 * Attempt to change to high-speed (if supported) 396 */ 397 err = mmc_switch_hs(card); 398 if (err != MMC_ERR_NONE) 399 goto free_card; 400 401 /* 402 * Compute bus speed. 403 */ 404 max_dtr = (unsigned int)-1; 405 406 if (mmc_card_highspeed(card)) { 407 if (max_dtr > card->sw_caps.hs_max_dtr) 408 max_dtr = card->sw_caps.hs_max_dtr; 409 } else if (max_dtr > card->csd.max_dtr) { 410 max_dtr = card->csd.max_dtr; 411 } 412 413 mmc_set_clock(host, max_dtr); 414 415 /* 416 * Switch to wider bus (if supported). 417 */ 418 if ((host->caps & MMC_CAP_4_BIT_DATA) && 419 (card->scr.bus_widths & SD_SCR_BUS_WIDTH_4)) { 420 err = mmc_app_set_bus_width(card, MMC_BUS_WIDTH_4); 421 if (err != MMC_ERR_NONE) 422 goto free_card; 423 424 mmc_set_bus_width(host, MMC_BUS_WIDTH_4); 425 } 426 427 /* 428 * Check if read-only switch is active. 429 */ 430 if (!oldcard) { 431 if (!host->ops->get_ro) { 432 printk(KERN_WARNING "%s: host does not " 433 "support reading read-only " 434 "switch. assuming write-enable.\n", 435 mmc_hostname(host)); 436 } else { 437 if (host->ops->get_ro(host)) 438 mmc_card_set_readonly(card); 439 } 440 } 441 442 if (!oldcard) 443 host->card = card; 444 445 return MMC_ERR_NONE; 446 447 free_card: 448 if (!oldcard) 449 mmc_remove_card(card); 450 err: 451 452 return MMC_ERR_FAILED; 453 } 454 455 /* 456 * Host is being removed. Free up the current card. 457 */ 458 static void mmc_sd_remove(struct mmc_host *host) 459 { 460 BUG_ON(!host); 461 BUG_ON(!host->card); 462 463 mmc_remove_card(host->card); 464 host->card = NULL; 465 } 466 467 /* 468 * Card detection callback from host. 469 */ 470 static void mmc_sd_detect(struct mmc_host *host) 471 { 472 int err; 473 474 BUG_ON(!host); 475 BUG_ON(!host->card); 476 477 mmc_claim_host(host); 478 479 /* 480 * Just check if our card has been removed. 481 */ 482 err = mmc_send_status(host->card, NULL); 483 484 mmc_release_host(host); 485 486 if (err != MMC_ERR_NONE) { 487 mmc_sd_remove(host); 488 489 mmc_claim_host(host); 490 mmc_detach_bus(host); 491 mmc_release_host(host); 492 } 493 } 494 495 MMC_ATTR_FN(cid, "%08x%08x%08x%08x\n", card->raw_cid[0], card->raw_cid[1], 496 card->raw_cid[2], card->raw_cid[3]); 497 MMC_ATTR_FN(csd, "%08x%08x%08x%08x\n", card->raw_csd[0], card->raw_csd[1], 498 card->raw_csd[2], card->raw_csd[3]); 499 MMC_ATTR_FN(scr, "%08x%08x\n", card->raw_scr[0], card->raw_scr[1]); 500 MMC_ATTR_FN(date, "%02d/%04d\n", card->cid.month, card->cid.year); 501 MMC_ATTR_FN(fwrev, "0x%x\n", card->cid.fwrev); 502 MMC_ATTR_FN(hwrev, "0x%x\n", card->cid.hwrev); 503 MMC_ATTR_FN(manfid, "0x%06x\n", card->cid.manfid); 504 MMC_ATTR_FN(name, "%s\n", card->cid.prod_name); 505 MMC_ATTR_FN(oemid, "0x%04x\n", card->cid.oemid); 506 MMC_ATTR_FN(serial, "0x%08x\n", card->cid.serial); 507 508 static struct device_attribute mmc_sd_dev_attrs[] = { 509 MMC_ATTR_RO(cid), 510 MMC_ATTR_RO(csd), 511 MMC_ATTR_RO(scr), 512 MMC_ATTR_RO(date), 513 MMC_ATTR_RO(fwrev), 514 MMC_ATTR_RO(hwrev), 515 MMC_ATTR_RO(manfid), 516 MMC_ATTR_RO(name), 517 MMC_ATTR_RO(oemid), 518 MMC_ATTR_RO(serial), 519 __ATTR_NULL, 520 }; 521 522 /* 523 * Adds sysfs entries as relevant. 524 */ 525 static int mmc_sd_sysfs_add(struct mmc_host *host, struct mmc_card *card) 526 { 527 int ret; 528 529 ret = mmc_add_attrs(card, mmc_sd_dev_attrs); 530 if (ret < 0) 531 return ret; 532 533 return 0; 534 } 535 536 /* 537 * Removes the sysfs entries added by mmc_sysfs_add(). 538 */ 539 static void mmc_sd_sysfs_remove(struct mmc_host *host, struct mmc_card *card) 540 { 541 mmc_remove_attrs(card, mmc_sd_dev_attrs); 542 } 543 544 #ifdef CONFIG_MMC_UNSAFE_RESUME 545 546 /* 547 * Suspend callback from host. 548 */ 549 static void mmc_sd_suspend(struct mmc_host *host) 550 { 551 BUG_ON(!host); 552 BUG_ON(!host->card); 553 554 mmc_claim_host(host); 555 mmc_deselect_cards(host); 556 host->card->state &= ~MMC_STATE_HIGHSPEED; 557 mmc_release_host(host); 558 } 559 560 /* 561 * Resume callback from host. 562 * 563 * This function tries to determine if the same card is still present 564 * and, if so, restore all state to it. 565 */ 566 static void mmc_sd_resume(struct mmc_host *host) 567 { 568 int err; 569 570 BUG_ON(!host); 571 BUG_ON(!host->card); 572 573 mmc_claim_host(host); 574 err = mmc_sd_init_card(host, host->ocr, host->card); 575 mmc_release_host(host); 576 577 if (err != MMC_ERR_NONE) { 578 mmc_sd_remove(host); 579 580 mmc_claim_host(host); 581 mmc_detach_bus(host); 582 mmc_release_host(host); 583 } 584 585 } 586 587 #else 588 589 #define mmc_sd_suspend NULL 590 #define mmc_sd_resume NULL 591 592 #endif 593 594 static const struct mmc_bus_ops mmc_sd_ops = { 595 .remove = mmc_sd_remove, 596 .detect = mmc_sd_detect, 597 .sysfs_add = mmc_sd_sysfs_add, 598 .sysfs_remove = mmc_sd_sysfs_remove, 599 .suspend = mmc_sd_suspend, 600 .resume = mmc_sd_resume, 601 }; 602 603 /* 604 * Starting point for SD card init. 605 */ 606 int mmc_attach_sd(struct mmc_host *host, u32 ocr) 607 { 608 int err; 609 610 BUG_ON(!host); 611 BUG_ON(!host->claimed); 612 613 mmc_attach_bus(host, &mmc_sd_ops); 614 615 /* 616 * Sanity check the voltages that the card claims to 617 * support. 618 */ 619 if (ocr & 0x7F) { 620 printk(KERN_WARNING "%s: card claims to support voltages " 621 "below the defined range. These will be ignored.\n", 622 mmc_hostname(host)); 623 ocr &= ~0x7F; 624 } 625 626 if (ocr & MMC_VDD_165_195) { 627 printk(KERN_WARNING "%s: SD card claims to support the " 628 "incompletely defined 'low voltage range'. This " 629 "will be ignored.\n", mmc_hostname(host)); 630 ocr &= ~MMC_VDD_165_195; 631 } 632 633 host->ocr = mmc_select_voltage(host, ocr); 634 635 /* 636 * Can we support the voltage(s) of the card(s)? 637 */ 638 if (!host->ocr) { 639 err = -EINVAL; 640 goto err; 641 } 642 643 /* 644 * Detect and init the card. 645 */ 646 err = mmc_sd_init_card(host, host->ocr, NULL); 647 if (err != MMC_ERR_NONE) 648 goto err; 649 650 mmc_release_host(host); 651 652 err = mmc_add_card(host->card); 653 if (err) 654 goto remove_card; 655 656 return 0; 657 658 remove_card: 659 mmc_remove_card(host->card); 660 host->card = NULL; 661 mmc_claim_host(host); 662 err: 663 mmc_detach_bus(host); 664 mmc_release_host(host); 665 666 printk(KERN_ERR "%s: error %d whilst initialising SD card\n", 667 mmc_hostname(host), err); 668 669 return 0; 670 } 671 672