sd.c 12.9 KB
Newer Older
P
Pierre Ossman 已提交
1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17
/*
 *  linux/drivers/mmc/sd.c
 *
 *  Copyright (C) 2003-2004 Russell King, All Rights Reserved.
 *  SD support Copyright (C) 2004 Ian Molton, All Rights Reserved.
 *  Copyright (C) 2005-2007 Pierre Ossman, All Rights Reserved.
 *
 * This program is free software; you can redistribute it and/or modify
 * it under the terms of the GNU General Public License version 2 as
 * published by the Free Software Foundation.
 */

#include <linux/err.h>

#include <linux/mmc/host.h>
#include <linux/mmc/card.h>
#include <linux/mmc/mmc.h>
18
#include <linux/mmc/sd.h>
P
Pierre Ossman 已提交
19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50 51 52 53 54 55 56 57 58 59 60 61 62 63 64 65 66 67 68 69 70 71 72 73 74 75 76 77 78 79 80 81 82 83 84 85 86 87 88 89 90 91

#include "core.h"
#include "sysfs.h"
#include "mmc_ops.h"
#include "sd_ops.h"

#include "core.h"

static const unsigned int tran_exp[] = {
	10000,		100000,		1000000,	10000000,
	0,		0,		0,		0
};

static const unsigned char tran_mant[] = {
	0,	10,	12,	13,	15,	20,	25,	30,
	35,	40,	45,	50,	55,	60,	70,	80,
};

static const unsigned int tacc_exp[] = {
	1,	10,	100,	1000,	10000,	100000,	1000000, 10000000,
};

static const unsigned int tacc_mant[] = {
	0,	10,	12,	13,	15,	20,	25,	30,
	35,	40,	45,	50,	55,	60,	70,	80,
};

#define UNSTUFF_BITS(resp,start,size)					\
	({								\
		const int __size = size;				\
		const u32 __mask = (__size < 32 ? 1 << __size : 0) - 1;	\
		const int __off = 3 - ((start) / 32);			\
		const int __shft = (start) & 31;			\
		u32 __res;						\
									\
		__res = resp[__off] >> __shft;				\
		if (__size + __shft > 32)				\
			__res |= resp[__off-1] << ((32 - __shft) % 32);	\
		__res & __mask;						\
	})

/*
 * Given the decoded CSD structure, decode the raw CID to our CID structure.
 */
static void mmc_decode_cid(struct mmc_card *card)
{
	u32 *resp = card->raw_cid;

	memset(&card->cid, 0, sizeof(struct mmc_cid));

	/*
	 * SD doesn't currently have a version field so we will
	 * have to assume we can parse this.
	 */
	card->cid.manfid		= UNSTUFF_BITS(resp, 120, 8);
	card->cid.oemid			= UNSTUFF_BITS(resp, 104, 16);
	card->cid.prod_name[0]		= UNSTUFF_BITS(resp, 96, 8);
	card->cid.prod_name[1]		= UNSTUFF_BITS(resp, 88, 8);
	card->cid.prod_name[2]		= UNSTUFF_BITS(resp, 80, 8);
	card->cid.prod_name[3]		= UNSTUFF_BITS(resp, 72, 8);
	card->cid.prod_name[4]		= UNSTUFF_BITS(resp, 64, 8);
	card->cid.hwrev			= UNSTUFF_BITS(resp, 60, 4);
	card->cid.fwrev			= UNSTUFF_BITS(resp, 56, 4);
	card->cid.serial		= UNSTUFF_BITS(resp, 24, 32);
	card->cid.year			= UNSTUFF_BITS(resp, 12, 8);
	card->cid.month			= UNSTUFF_BITS(resp, 8, 4);

	card->cid.year += 2000; /* SD cards year offset */
}

/*
 * Given a 128-bit response, decode to our card CSD structure.
 */
P
Pierre Ossman 已提交
92
static int mmc_decode_csd(struct mmc_card *card)
P
Pierre Ossman 已提交
93 94 95 96 97 98 99 100 101 102 103 104 105 106 107 108 109 110 111 112 113 114 115 116 117 118 119 120 121 122 123 124 125 126 127 128 129 130 131 132 133 134 135 136 137 138 139 140 141 142 143 144 145 146 147 148 149 150 151 152 153 154
{
	struct mmc_csd *csd = &card->csd;
	unsigned int e, m, csd_struct;
	u32 *resp = card->raw_csd;

	csd_struct = UNSTUFF_BITS(resp, 126, 2);

	switch (csd_struct) {
	case 0:
		m = UNSTUFF_BITS(resp, 115, 4);
		e = UNSTUFF_BITS(resp, 112, 3);
		csd->tacc_ns	 = (tacc_exp[e] * tacc_mant[m] + 9) / 10;
		csd->tacc_clks	 = UNSTUFF_BITS(resp, 104, 8) * 100;

		m = UNSTUFF_BITS(resp, 99, 4);
		e = UNSTUFF_BITS(resp, 96, 3);
		csd->max_dtr	  = tran_exp[e] * tran_mant[m];
		csd->cmdclass	  = UNSTUFF_BITS(resp, 84, 12);

		e = UNSTUFF_BITS(resp, 47, 3);
		m = UNSTUFF_BITS(resp, 62, 12);
		csd->capacity	  = (1 + m) << (e + 2);

		csd->read_blkbits = UNSTUFF_BITS(resp, 80, 4);
		csd->read_partial = UNSTUFF_BITS(resp, 79, 1);
		csd->write_misalign = UNSTUFF_BITS(resp, 78, 1);
		csd->read_misalign = UNSTUFF_BITS(resp, 77, 1);
		csd->r2w_factor = UNSTUFF_BITS(resp, 26, 3);
		csd->write_blkbits = UNSTUFF_BITS(resp, 22, 4);
		csd->write_partial = UNSTUFF_BITS(resp, 21, 1);
		break;
	case 1:
		/*
		 * This is a block-addressed SDHC card. Most
		 * interesting fields are unused and have fixed
		 * values. To avoid getting tripped by buggy cards,
		 * we assume those fixed values ourselves.
		 */
		mmc_card_set_blockaddr(card);

		csd->tacc_ns	 = 0; /* Unused */
		csd->tacc_clks	 = 0; /* Unused */

		m = UNSTUFF_BITS(resp, 99, 4);
		e = UNSTUFF_BITS(resp, 96, 3);
		csd->max_dtr	  = tran_exp[e] * tran_mant[m];
		csd->cmdclass	  = UNSTUFF_BITS(resp, 84, 12);

		m = UNSTUFF_BITS(resp, 48, 22);
		csd->capacity     = (1 + m) << 10;

		csd->read_blkbits = 9;
		csd->read_partial = 0;
		csd->write_misalign = 0;
		csd->read_misalign = 0;
		csd->r2w_factor = 4; /* Unused */
		csd->write_blkbits = 9;
		csd->write_partial = 0;
		break;
	default:
		printk("%s: unrecognised CSD structure version %d\n",
			mmc_hostname(card->host), csd_struct);
P
Pierre Ossman 已提交
155
		return -EINVAL;
P
Pierre Ossman 已提交
156
	}
P
Pierre Ossman 已提交
157 158

	return 0;
P
Pierre Ossman 已提交
159 160 161 162 163
}

/*
 * Given a 64-bit response, decode to our card SCR structure.
 */
P
Pierre Ossman 已提交
164
static int mmc_decode_scr(struct mmc_card *card)
P
Pierre Ossman 已提交
165 166 167 168 169 170 171 172 173 174 175 176 177 178
{
	struct sd_scr *scr = &card->scr;
	unsigned int scr_struct;
	u32 resp[4];

	BUG_ON(!mmc_card_sd(card));

	resp[3] = card->raw_scr[1];
	resp[2] = card->raw_scr[0];

	scr_struct = UNSTUFF_BITS(resp, 60, 4);
	if (scr_struct != 0) {
		printk("%s: unrecognised SCR structure version %d\n",
			mmc_hostname(card->host), scr_struct);
P
Pierre Ossman 已提交
179
		return -EINVAL;
P
Pierre Ossman 已提交
180 181 182 183
	}

	scr->sda_vsn = UNSTUFF_BITS(resp, 56, 4);
	scr->bus_widths = UNSTUFF_BITS(resp, 48, 4);
P
Pierre Ossman 已提交
184 185

	return 0;
P
Pierre Ossman 已提交
186 187 188
}

/*
P
Pierre Ossman 已提交
189
 * Fetches and decodes switch information
P
Pierre Ossman 已提交
190
 */
P
Pierre Ossman 已提交
191
static int mmc_read_switch(struct mmc_card *card)
P
Pierre Ossman 已提交
192 193 194 195
{
	int err;
	u8 *status;

196 197 198 199 200 201 202 203 204 205
	if (card->scr.sda_vsn < SCR_SPEC_VER_1)
		return MMC_ERR_NONE;

	if (!(card->csd.cmdclass & CCC_SWITCH)) {
		printk(KERN_WARNING "%s: card lacks mandatory switch "
			"function, performance might suffer.\n",
			mmc_hostname(card->host));
		return MMC_ERR_NONE;
	}

P
Pierre Ossman 已提交
206 207 208 209 210 211 212 213 214 215 216 217
	err = MMC_ERR_FAILED;

	status = kmalloc(64, GFP_KERNEL);
	if (!status) {
		printk("%s: could not allocate a buffer for switch "
		       "capabilities.\n",
			mmc_hostname(card->host));
		return err;
	}

	err = mmc_sd_switch(card, 0, 0, 1, status);
	if (err != MMC_ERR_NONE) {
218 219 220
		printk(KERN_WARNING "%s: problem reading switch "
			"capabilities, performance might suffer.\n",
			mmc_hostname(card->host));
P
Pierre Ossman 已提交
221
		err = MMC_ERR_NONE;
P
Pierre Ossman 已提交
222 223 224 225 226 227
		goto out;
	}

	if (status[13] & 0x02)
		card->sw_caps.hs_max_dtr = 50000000;

P
Pierre Ossman 已提交
228 229 230 231 232 233 234 235 236 237 238 239 240 241
out:
	kfree(status);

	return err;
}

/*
 * Test if the card supports high-speed mode and, if so, switch to it.
 */
static int mmc_switch_hs(struct mmc_card *card)
{
	int err;
	u8 *status;

242 243 244 245 246 247
	if (card->scr.sda_vsn < SCR_SPEC_VER_1)
		return MMC_ERR_NONE;

	if (!(card->csd.cmdclass & CCC_SWITCH))
		return MMC_ERR_NONE;

P
Pierre Ossman 已提交
248 249 250 251 252 253 254 255 256 257 258 259 260 261 262 263
	if (!(card->host->caps & MMC_CAP_SD_HIGHSPEED))
		return MMC_ERR_NONE;

	if (card->sw_caps.hs_max_dtr == 0)
		return MMC_ERR_NONE;

	err = MMC_ERR_FAILED;

	status = kmalloc(64, GFP_KERNEL);
	if (!status) {
		printk("%s: could not allocate a buffer for switch "
		       "capabilities.\n",
			mmc_hostname(card->host));
		return err;
	}

P
Pierre Ossman 已提交
264 265 266 267 268 269 270 271 272 273 274 275 276 277 278 279 280 281 282 283
	err = mmc_sd_switch(card, 1, 0, 1, status);
	if (err != MMC_ERR_NONE)
		goto out;

	if ((status[16] & 0xF) != 1) {
		printk(KERN_WARNING "%s: Problem switching card "
			"into high-speed mode!\n",
			mmc_hostname(card->host));
	} else {
		mmc_card_set_highspeed(card);
		mmc_set_timing(card->host, MMC_TIMING_SD_HS);
	}

out:
	kfree(status);

	return err;
}

/*
284 285 286 287
 * Handle the detection and initialisation of a card.
 *
 * In the case of a resume, "curcard" will contain the card
 * we're trying to reinitialise.
P
Pierre Ossman 已提交
288
 */
289 290
static int mmc_sd_init_card(struct mmc_host *host, u32 ocr,
	struct mmc_card *oldcard)
P
Pierre Ossman 已提交
291 292 293 294 295 296 297 298 299 300 301 302 303 304 305 306 307 308 309 310 311 312 313
{
	struct mmc_card *card;
	int err;
	u32 cid[4];
	unsigned int max_dtr;

	BUG_ON(!host);
	BUG_ON(!host->claimed);

	/*
	 * Since we're changing the OCR value, we seem to
	 * need to tell some cards to go back to the idle
	 * state.  We wait 1ms to give cards time to
	 * respond.
	 */
	mmc_go_idle(host);

	/*
	 * If SD_SEND_IF_COND indicates an SD 2.0
	 * compliant card and we should set bit 30
	 * of the ocr to indicate that we can handle
	 * block-addressed SDHC cards.
	 */
314
	err = mmc_send_if_cond(host, ocr);
P
Pierre Ossman 已提交
315
	if (err == MMC_ERR_NONE)
316
		ocr |= 1 << 30;
P
Pierre Ossman 已提交
317

318 319 320
	err = mmc_send_app_op_cond(host, ocr, NULL);
	if (err != MMC_ERR_NONE)
		goto err;
P
Pierre Ossman 已提交
321 322 323 324 325 326 327 328

	/*
	 * Fetch CID from card.
	 */
	err = mmc_all_send_cid(host, cid);
	if (err != MMC_ERR_NONE)
		goto err;

329 330 331
	if (oldcard) {
		if (memcmp(cid, oldcard->raw_cid, sizeof(cid)) != 0)
			goto err;
P
Pierre Ossman 已提交
332

333 334 335 336 337 338 339 340 341 342 343 344
		card = oldcard;
	} else {
		/*
		 * Allocate card structure.
		 */
		card = mmc_alloc_card(host);
		if (IS_ERR(card))
			goto err;

		card->type = MMC_TYPE_SD;
		memcpy(card->raw_cid, cid, sizeof(card->raw_cid));
	}
P
Pierre Ossman 已提交
345 346 347 348 349 350 351 352 353 354

	/*
	 * Set card RCA.
	 */
	err = mmc_send_relative_addr(host, &card->rca);
	if (err != MMC_ERR_NONE)
		goto free_card;

	mmc_set_bus_mode(host, MMC_BUSMODE_PUSHPULL);

355 356 357 358 359 360 361
	if (!oldcard) {
		/*
		 * Fetch CSD from card.
		 */
		err = mmc_send_csd(card, card->raw_csd);
		if (err != MMC_ERR_NONE)
			goto free_card;
P
Pierre Ossman 已提交
362

P
Pierre Ossman 已提交
363 364 365 366
		err = mmc_decode_csd(card);
		if (err < 0)
			goto free_card;

367 368
		mmc_decode_cid(card);
	}
P
Pierre Ossman 已提交
369 370

	/*
371
	 * Select card, as all following commands rely on that.
P
Pierre Ossman 已提交
372 373 374 375 376
	 */
	err = mmc_select_card(card);
	if (err != MMC_ERR_NONE)
		goto free_card;

377 378 379 380 381 382 383
	if (!oldcard) {
		/*
		 * Fetch SCR from card.
		 */
		err = mmc_app_send_scr(card, card->raw_scr);
		if (err != MMC_ERR_NONE)
			goto free_card;
P
Pierre Ossman 已提交
384

P
Pierre Ossman 已提交
385 386 387
		err = mmc_decode_scr(card);
		if (err < 0)
			goto free_card;
P
Pierre Ossman 已提交
388

389 390 391 392 393 394 395
		/*
		 * Fetch switch information from card.
		 */
		err = mmc_read_switch(card);
		if (err != MMC_ERR_NONE)
			goto free_card;
	}
P
Pierre Ossman 已提交
396 397 398

	/*
	 * Attempt to change to high-speed (if supported)
P
Pierre Ossman 已提交
399 400 401 402 403 404 405 406 407 408 409 410 411 412 413 414 415 416 417 418 419 420
	 */
	err = mmc_switch_hs(card);
	if (err != MMC_ERR_NONE)
		goto free_card;

	/*
	 * Compute bus speed.
	 */
	max_dtr = (unsigned int)-1;

	if (mmc_card_highspeed(card)) {
		if (max_dtr > card->sw_caps.hs_max_dtr)
			max_dtr = card->sw_caps.hs_max_dtr;
	} else if (max_dtr > card->csd.max_dtr) {
		max_dtr = card->csd.max_dtr;
	}

	mmc_set_clock(host, max_dtr);

	/*
	 * Switch to wider bus (if supported).
	 */
P
Pierre Ossman 已提交
421
	if ((host->caps & MMC_CAP_4_BIT_DATA) &&
P
Pierre Ossman 已提交
422 423 424 425 426 427 428 429
		(card->scr.bus_widths & SD_SCR_BUS_WIDTH_4)) {
		err = mmc_app_set_bus_width(card, MMC_BUS_WIDTH_4);
		if (err != MMC_ERR_NONE)
			goto free_card;

		mmc_set_bus_width(host, MMC_BUS_WIDTH_4);
	}

430 431 432 433 434 435 436 437 438 439 440 441 442 443 444
	/*
	 * Check if read-only switch is active.
	 */
	if (!oldcard) {
		if (!host->ops->get_ro) {
			printk(KERN_WARNING "%s: host does not "
				"support reading read-only "
				"switch. assuming write-enable.\n",
				mmc_hostname(host));
		} else {
			if (host->ops->get_ro(host))
				mmc_card_set_readonly(card);
		}
	}

445 446 447 448 449 450 451 452 453 454 455 456 457 458 459 460 461 462 463 464 465 466 467 468 469 470 471 472 473 474 475 476 477 478 479 480 481 482 483 484 485
	if (!oldcard)
		host->card = card;

	return MMC_ERR_NONE;

free_card:
	if (!oldcard)
		mmc_remove_card(card);
err:

	return MMC_ERR_FAILED;
}

/*
 * Host is being removed. Free up the current card.
 */
static void mmc_sd_remove(struct mmc_host *host)
{
	BUG_ON(!host);
	BUG_ON(!host->card);

	mmc_remove_card(host->card);
	host->card = NULL;
}

/*
 * Card detection callback from host.
 */
static void mmc_sd_detect(struct mmc_host *host)
{
	int err;

	BUG_ON(!host);
	BUG_ON(!host->card);

	mmc_claim_host(host);

	/*
	 * Just check if our card has been removed.
	 */
	err = mmc_send_status(host->card, NULL);
P
Pierre Ossman 已提交
486 487 488

	mmc_release_host(host);

489 490 491 492 493 494 495 496 497 498 499 500 501 502 503 504 505 506 507 508 509 510 511 512 513 514 515 516 517 518 519 520 521 522 523 524 525 526 527 528 529 530 531 532 533 534 535 536 537 538 539 540 541 542 543 544 545 546 547 548 549 550 551 552 553 554 555 556 557 558 559 560 561 562 563 564 565 566 567 568 569 570 571 572 573 574 575 576 577 578 579 580 581 582 583 584 585 586 587 588 589 590 591 592 593 594 595 596 597 598 599 600 601 602
	if (err != MMC_ERR_NONE) {
		mmc_remove_card(host->card);
		host->card = NULL;

		mmc_claim_host(host);
		mmc_detach_bus(host);
		mmc_release_host(host);
	}
}

#ifdef CONFIG_MMC_UNSAFE_RESUME

/*
 * Suspend callback from host.
 */
static void mmc_sd_suspend(struct mmc_host *host)
{
	BUG_ON(!host);
	BUG_ON(!host->card);

	mmc_claim_host(host);
	mmc_deselect_cards(host);
	host->card->state &= ~MMC_STATE_HIGHSPEED;
	mmc_release_host(host);
}

/*
 * Resume callback from host.
 *
 * This function tries to determine if the same card is still present
 * and, if so, restore all state to it.
 */
static void mmc_sd_resume(struct mmc_host *host)
{
	int err;

	BUG_ON(!host);
	BUG_ON(!host->card);

	mmc_claim_host(host);

	err = mmc_sd_init_card(host, host->ocr, host->card);
	if (err != MMC_ERR_NONE) {
		mmc_remove_card(host->card);
		host->card = NULL;

		mmc_detach_bus(host);
	}

	mmc_release_host(host);
}

#else

#define mmc_sd_suspend NULL
#define mmc_sd_resume NULL

#endif

static const struct mmc_bus_ops mmc_sd_ops = {
	.remove = mmc_sd_remove,
	.detect = mmc_sd_detect,
	.suspend = mmc_sd_suspend,
	.resume = mmc_sd_resume,
};

/*
 * Starting point for SD card init.
 */
int mmc_attach_sd(struct mmc_host *host, u32 ocr)
{
	int err;

	BUG_ON(!host);
	BUG_ON(!host->claimed);

	mmc_attach_bus(host, &mmc_sd_ops);

	/*
	 * Sanity check the voltages that the card claims to
	 * support.
	 */
	if (ocr & 0x7F) {
		printk(KERN_WARNING "%s: card claims to support voltages "
		       "below the defined range. These will be ignored.\n",
		       mmc_hostname(host));
		ocr &= ~0x7F;
	}

	if (ocr & MMC_VDD_165_195) {
		printk(KERN_WARNING "%s: SD card claims to support the "
		       "incompletely defined 'low voltage range'. This "
		       "will be ignored.\n", mmc_hostname(host));
		ocr &= ~MMC_VDD_165_195;
	}

	host->ocr = mmc_select_voltage(host, ocr);

	/*
	 * Can we support the voltage(s) of the card(s)?
	 */
	if (!host->ocr)
		goto err;

	/*
	 * Detect and init the card.
	 */
	err = mmc_sd_init_card(host, host->ocr, NULL);
	if (err != MMC_ERR_NONE)
		goto err;

	mmc_release_host(host);

	err = mmc_register_card(host->card);
P
Pierre Ossman 已提交
603 604 605 606 607 608 609
	if (err)
		goto reclaim_host;

	return 0;

reclaim_host:
	mmc_claim_host(host);
610
	mmc_remove_card(host->card);
P
Pierre Ossman 已提交
611 612 613 614 615 616 617 618
	host->card = NULL;
err:
	mmc_detach_bus(host);
	mmc_release_host(host);

	return 0;
}