xref: /openbmc/linux/drivers/mmc/core/mmc.c (revision dfe86cba)
1 /*
2  *  linux/drivers/mmc/core/mmc.c
3  *
4  *  Copyright (C) 2003-2004 Russell King, All Rights Reserved.
5  *  Copyright (C) 2005-2007 Pierre Ossman, All Rights Reserved.
6  *  MMCv4 support Copyright (C) 2006 Philip Langdale, 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 
20 #include "core.h"
21 #include "bus.h"
22 #include "mmc_ops.h"
23 
24 static const unsigned int tran_exp[] = {
25 	10000,		100000,		1000000,	10000000,
26 	0,		0,		0,		0
27 };
28 
29 static const unsigned char tran_mant[] = {
30 	0,	10,	12,	13,	15,	20,	25,	30,
31 	35,	40,	45,	50,	55,	60,	70,	80,
32 };
33 
34 static const unsigned int tacc_exp[] = {
35 	1,	10,	100,	1000,	10000,	100000,	1000000, 10000000,
36 };
37 
38 static const unsigned int tacc_mant[] = {
39 	0,	10,	12,	13,	15,	20,	25,	30,
40 	35,	40,	45,	50,	55,	60,	70,	80,
41 };
42 
43 #define UNSTUFF_BITS(resp,start,size)					\
44 	({								\
45 		const int __size = size;				\
46 		const u32 __mask = (__size < 32 ? 1 << __size : 0) - 1;	\
47 		const int __off = 3 - ((start) / 32);			\
48 		const int __shft = (start) & 31;			\
49 		u32 __res;						\
50 									\
51 		__res = resp[__off] >> __shft;				\
52 		if (__size + __shft > 32)				\
53 			__res |= resp[__off-1] << ((32 - __shft) % 32);	\
54 		__res & __mask;						\
55 	})
56 
57 /*
58  * Given the decoded CSD structure, decode the raw CID to our CID structure.
59  */
60 static int mmc_decode_cid(struct mmc_card *card)
61 {
62 	u32 *resp = card->raw_cid;
63 
64 	/*
65 	 * The selection of the format here is based upon published
66 	 * specs from sandisk and from what people have reported.
67 	 */
68 	switch (card->csd.mmca_vsn) {
69 	case 0: /* MMC v1.0 - v1.2 */
70 	case 1: /* MMC v1.4 */
71 		card->cid.manfid	= UNSTUFF_BITS(resp, 104, 24);
72 		card->cid.prod_name[0]	= UNSTUFF_BITS(resp, 96, 8);
73 		card->cid.prod_name[1]	= UNSTUFF_BITS(resp, 88, 8);
74 		card->cid.prod_name[2]	= UNSTUFF_BITS(resp, 80, 8);
75 		card->cid.prod_name[3]	= UNSTUFF_BITS(resp, 72, 8);
76 		card->cid.prod_name[4]	= UNSTUFF_BITS(resp, 64, 8);
77 		card->cid.prod_name[5]	= UNSTUFF_BITS(resp, 56, 8);
78 		card->cid.prod_name[6]	= UNSTUFF_BITS(resp, 48, 8);
79 		card->cid.hwrev		= UNSTUFF_BITS(resp, 44, 4);
80 		card->cid.fwrev		= UNSTUFF_BITS(resp, 40, 4);
81 		card->cid.serial	= UNSTUFF_BITS(resp, 16, 24);
82 		card->cid.month		= UNSTUFF_BITS(resp, 12, 4);
83 		card->cid.year		= UNSTUFF_BITS(resp, 8, 4) + 1997;
84 		break;
85 
86 	case 2: /* MMC v2.0 - v2.2 */
87 	case 3: /* MMC v3.1 - v3.3 */
88 	case 4: /* MMC v4 */
89 		card->cid.manfid	= UNSTUFF_BITS(resp, 120, 8);
90 		card->cid.oemid		= UNSTUFF_BITS(resp, 104, 16);
91 		card->cid.prod_name[0]	= UNSTUFF_BITS(resp, 96, 8);
92 		card->cid.prod_name[1]	= UNSTUFF_BITS(resp, 88, 8);
93 		card->cid.prod_name[2]	= UNSTUFF_BITS(resp, 80, 8);
94 		card->cid.prod_name[3]	= UNSTUFF_BITS(resp, 72, 8);
95 		card->cid.prod_name[4]	= UNSTUFF_BITS(resp, 64, 8);
96 		card->cid.prod_name[5]	= UNSTUFF_BITS(resp, 56, 8);
97 		card->cid.serial	= UNSTUFF_BITS(resp, 16, 32);
98 		card->cid.month		= UNSTUFF_BITS(resp, 12, 4);
99 		card->cid.year		= UNSTUFF_BITS(resp, 8, 4) + 1997;
100 		break;
101 
102 	default:
103 		printk(KERN_ERR "%s: card has unknown MMCA version %d\n",
104 			mmc_hostname(card->host), card->csd.mmca_vsn);
105 		return -EINVAL;
106 	}
107 
108 	return 0;
109 }
110 
111 static void mmc_set_erase_size(struct mmc_card *card)
112 {
113 	if (card->ext_csd.erase_group_def & 1)
114 		card->erase_size = card->ext_csd.hc_erase_size;
115 	else
116 		card->erase_size = card->csd.erase_size;
117 
118 	mmc_init_erase(card);
119 }
120 
121 /*
122  * Given a 128-bit response, decode to our card CSD structure.
123  */
124 static int mmc_decode_csd(struct mmc_card *card)
125 {
126 	struct mmc_csd *csd = &card->csd;
127 	unsigned int e, m, a, b;
128 	u32 *resp = card->raw_csd;
129 
130 	/*
131 	 * We only understand CSD structure v1.1 and v1.2.
132 	 * v1.2 has extra information in bits 15, 11 and 10.
133 	 * We also support eMMC v4.4 & v4.41.
134 	 */
135 	csd->structure = UNSTUFF_BITS(resp, 126, 2);
136 	if (csd->structure == 0) {
137 		printk(KERN_ERR "%s: unrecognised CSD structure version %d\n",
138 			mmc_hostname(card->host), csd->structure);
139 		return -EINVAL;
140 	}
141 
142 	csd->mmca_vsn	 = UNSTUFF_BITS(resp, 122, 4);
143 	m = UNSTUFF_BITS(resp, 115, 4);
144 	e = UNSTUFF_BITS(resp, 112, 3);
145 	csd->tacc_ns	 = (tacc_exp[e] * tacc_mant[m] + 9) / 10;
146 	csd->tacc_clks	 = UNSTUFF_BITS(resp, 104, 8) * 100;
147 
148 	m = UNSTUFF_BITS(resp, 99, 4);
149 	e = UNSTUFF_BITS(resp, 96, 3);
150 	csd->max_dtr	  = tran_exp[e] * tran_mant[m];
151 	csd->cmdclass	  = UNSTUFF_BITS(resp, 84, 12);
152 
153 	e = UNSTUFF_BITS(resp, 47, 3);
154 	m = UNSTUFF_BITS(resp, 62, 12);
155 	csd->capacity	  = (1 + m) << (e + 2);
156 
157 	csd->read_blkbits = UNSTUFF_BITS(resp, 80, 4);
158 	csd->read_partial = UNSTUFF_BITS(resp, 79, 1);
159 	csd->write_misalign = UNSTUFF_BITS(resp, 78, 1);
160 	csd->read_misalign = UNSTUFF_BITS(resp, 77, 1);
161 	csd->r2w_factor = UNSTUFF_BITS(resp, 26, 3);
162 	csd->write_blkbits = UNSTUFF_BITS(resp, 22, 4);
163 	csd->write_partial = UNSTUFF_BITS(resp, 21, 1);
164 
165 	if (csd->write_blkbits >= 9) {
166 		a = UNSTUFF_BITS(resp, 42, 5);
167 		b = UNSTUFF_BITS(resp, 37, 5);
168 		csd->erase_size = (a + 1) * (b + 1);
169 		csd->erase_size <<= csd->write_blkbits - 9;
170 	}
171 
172 	return 0;
173 }
174 
175 /*
176  * Read and decode extended CSD.
177  */
178 static int mmc_read_ext_csd(struct mmc_card *card)
179 {
180 	int err;
181 	u8 *ext_csd;
182 
183 	BUG_ON(!card);
184 
185 	if (card->csd.mmca_vsn < CSD_SPEC_VER_4)
186 		return 0;
187 
188 	/*
189 	 * As the ext_csd is so large and mostly unused, we don't store the
190 	 * raw block in mmc_card.
191 	 */
192 	ext_csd = kmalloc(512, GFP_KERNEL);
193 	if (!ext_csd) {
194 		printk(KERN_ERR "%s: could not allocate a buffer to "
195 			"receive the ext_csd.\n", mmc_hostname(card->host));
196 		return -ENOMEM;
197 	}
198 
199 	err = mmc_send_ext_csd(card, ext_csd);
200 	if (err) {
201 		/* If the host or the card can't do the switch,
202 		 * fail more gracefully. */
203 		if ((err != -EINVAL)
204 		 && (err != -ENOSYS)
205 		 && (err != -EFAULT))
206 			goto out;
207 
208 		/*
209 		 * High capacity cards should have this "magic" size
210 		 * stored in their CSD.
211 		 */
212 		if (card->csd.capacity == (4096 * 512)) {
213 			printk(KERN_ERR "%s: unable to read EXT_CSD "
214 				"on a possible high capacity card. "
215 				"Card will be ignored.\n",
216 				mmc_hostname(card->host));
217 		} else {
218 			printk(KERN_WARNING "%s: unable to read "
219 				"EXT_CSD, performance might "
220 				"suffer.\n",
221 				mmc_hostname(card->host));
222 			err = 0;
223 		}
224 
225 		goto out;
226 	}
227 
228 	/* Version is coded in the CSD_STRUCTURE byte in the EXT_CSD register */
229 	if (card->csd.structure == 3) {
230 		int ext_csd_struct = ext_csd[EXT_CSD_STRUCTURE];
231 		if (ext_csd_struct > 2) {
232 			printk(KERN_ERR "%s: unrecognised EXT_CSD structure "
233 				"version %d\n", mmc_hostname(card->host),
234 					ext_csd_struct);
235 			err = -EINVAL;
236 			goto out;
237 		}
238 	}
239 
240 	card->ext_csd.rev = ext_csd[EXT_CSD_REV];
241 	if (card->ext_csd.rev > 5) {
242 		printk(KERN_ERR "%s: unrecognised EXT_CSD revision %d\n",
243 			mmc_hostname(card->host), card->ext_csd.rev);
244 		err = -EINVAL;
245 		goto out;
246 	}
247 
248 	if (card->ext_csd.rev >= 2) {
249 		card->ext_csd.sectors =
250 			ext_csd[EXT_CSD_SEC_CNT + 0] << 0 |
251 			ext_csd[EXT_CSD_SEC_CNT + 1] << 8 |
252 			ext_csd[EXT_CSD_SEC_CNT + 2] << 16 |
253 			ext_csd[EXT_CSD_SEC_CNT + 3] << 24;
254 
255 		/* Cards with density > 2GiB are sector addressed */
256 		if (card->ext_csd.sectors > (2u * 1024 * 1024 * 1024) / 512)
257 			mmc_card_set_blockaddr(card);
258 	}
259 
260 	switch (ext_csd[EXT_CSD_CARD_TYPE] & EXT_CSD_CARD_TYPE_MASK) {
261 	case EXT_CSD_CARD_TYPE_52 | EXT_CSD_CARD_TYPE_26:
262 		card->ext_csd.hs_max_dtr = 52000000;
263 		break;
264 	case EXT_CSD_CARD_TYPE_26:
265 		card->ext_csd.hs_max_dtr = 26000000;
266 		break;
267 	default:
268 		/* MMC v4 spec says this cannot happen */
269 		printk(KERN_WARNING "%s: card is mmc v4 but doesn't "
270 			"support any high-speed modes.\n",
271 			mmc_hostname(card->host));
272 	}
273 
274 	if (card->ext_csd.rev >= 3) {
275 		u8 sa_shift = ext_csd[EXT_CSD_S_A_TIMEOUT];
276 
277 		/* Sleep / awake timeout in 100ns units */
278 		if (sa_shift > 0 && sa_shift <= 0x17)
279 			card->ext_csd.sa_timeout =
280 					1 << ext_csd[EXT_CSD_S_A_TIMEOUT];
281 		card->ext_csd.erase_group_def =
282 			ext_csd[EXT_CSD_ERASE_GROUP_DEF];
283 		card->ext_csd.hc_erase_timeout = 300 *
284 			ext_csd[EXT_CSD_ERASE_TIMEOUT_MULT];
285 		card->ext_csd.hc_erase_size =
286 			ext_csd[EXT_CSD_HC_ERASE_GRP_SIZE] << 10;
287 	}
288 
289 	if (card->ext_csd.rev >= 4) {
290 		card->ext_csd.sec_trim_mult =
291 			ext_csd[EXT_CSD_SEC_TRIM_MULT];
292 		card->ext_csd.sec_erase_mult =
293 			ext_csd[EXT_CSD_SEC_ERASE_MULT];
294 		card->ext_csd.sec_feature_support =
295 			ext_csd[EXT_CSD_SEC_FEATURE_SUPPORT];
296 		card->ext_csd.trim_timeout = 300 *
297 			ext_csd[EXT_CSD_TRIM_MULT];
298 	}
299 
300 	if (ext_csd[EXT_CSD_ERASED_MEM_CONT])
301 		card->erased_byte = 0xFF;
302 	else
303 		card->erased_byte = 0x0;
304 
305 out:
306 	kfree(ext_csd);
307 
308 	return err;
309 }
310 
311 MMC_DEV_ATTR(cid, "%08x%08x%08x%08x\n", card->raw_cid[0], card->raw_cid[1],
312 	card->raw_cid[2], card->raw_cid[3]);
313 MMC_DEV_ATTR(csd, "%08x%08x%08x%08x\n", card->raw_csd[0], card->raw_csd[1],
314 	card->raw_csd[2], card->raw_csd[3]);
315 MMC_DEV_ATTR(date, "%02d/%04d\n", card->cid.month, card->cid.year);
316 MMC_DEV_ATTR(erase_size, "%u\n", card->erase_size << 9);
317 MMC_DEV_ATTR(preferred_erase_size, "%u\n", card->pref_erase << 9);
318 MMC_DEV_ATTR(fwrev, "0x%x\n", card->cid.fwrev);
319 MMC_DEV_ATTR(hwrev, "0x%x\n", card->cid.hwrev);
320 MMC_DEV_ATTR(manfid, "0x%06x\n", card->cid.manfid);
321 MMC_DEV_ATTR(name, "%s\n", card->cid.prod_name);
322 MMC_DEV_ATTR(oemid, "0x%04x\n", card->cid.oemid);
323 MMC_DEV_ATTR(serial, "0x%08x\n", card->cid.serial);
324 
325 static struct attribute *mmc_std_attrs[] = {
326 	&dev_attr_cid.attr,
327 	&dev_attr_csd.attr,
328 	&dev_attr_date.attr,
329 	&dev_attr_erase_size.attr,
330 	&dev_attr_preferred_erase_size.attr,
331 	&dev_attr_fwrev.attr,
332 	&dev_attr_hwrev.attr,
333 	&dev_attr_manfid.attr,
334 	&dev_attr_name.attr,
335 	&dev_attr_oemid.attr,
336 	&dev_attr_serial.attr,
337 	NULL,
338 };
339 
340 static struct attribute_group mmc_std_attr_group = {
341 	.attrs = mmc_std_attrs,
342 };
343 
344 static const struct attribute_group *mmc_attr_groups[] = {
345 	&mmc_std_attr_group,
346 	NULL,
347 };
348 
349 static struct device_type mmc_type = {
350 	.groups = mmc_attr_groups,
351 };
352 
353 /*
354  * Handle the detection and initialisation of a card.
355  *
356  * In the case of a resume, "oldcard" will contain the card
357  * we're trying to reinitialise.
358  */
359 static int mmc_init_card(struct mmc_host *host, u32 ocr,
360 	struct mmc_card *oldcard)
361 {
362 	struct mmc_card *card;
363 	int err;
364 	u32 cid[4];
365 	unsigned int max_dtr;
366 
367 	BUG_ON(!host);
368 	WARN_ON(!host->claimed);
369 
370 	/*
371 	 * Since we're changing the OCR value, we seem to
372 	 * need to tell some cards to go back to the idle
373 	 * state.  We wait 1ms to give cards time to
374 	 * respond.
375 	 */
376 	mmc_go_idle(host);
377 
378 	/* The extra bit indicates that we support high capacity */
379 	err = mmc_send_op_cond(host, ocr | (1 << 30), NULL);
380 	if (err)
381 		goto err;
382 
383 	/*
384 	 * For SPI, enable CRC as appropriate.
385 	 */
386 	if (mmc_host_is_spi(host)) {
387 		err = mmc_spi_set_crc(host, use_spi_crc);
388 		if (err)
389 			goto err;
390 	}
391 
392 	/*
393 	 * Fetch CID from card.
394 	 */
395 	if (mmc_host_is_spi(host))
396 		err = mmc_send_cid(host, cid);
397 	else
398 		err = mmc_all_send_cid(host, cid);
399 	if (err)
400 		goto err;
401 
402 	if (oldcard) {
403 		if (memcmp(cid, oldcard->raw_cid, sizeof(cid)) != 0) {
404 			err = -ENOENT;
405 			goto err;
406 		}
407 
408 		card = oldcard;
409 	} else {
410 		/*
411 		 * Allocate card structure.
412 		 */
413 		card = mmc_alloc_card(host, &mmc_type);
414 		if (IS_ERR(card)) {
415 			err = PTR_ERR(card);
416 			goto err;
417 		}
418 
419 		card->type = MMC_TYPE_MMC;
420 		card->rca = 1;
421 		memcpy(card->raw_cid, cid, sizeof(card->raw_cid));
422 	}
423 
424 	/*
425 	 * For native busses:  set card RCA and quit open drain mode.
426 	 */
427 	if (!mmc_host_is_spi(host)) {
428 		err = mmc_set_relative_addr(card);
429 		if (err)
430 			goto free_card;
431 
432 		mmc_set_bus_mode(host, MMC_BUSMODE_PUSHPULL);
433 	}
434 
435 	if (!oldcard) {
436 		/*
437 		 * Fetch CSD from card.
438 		 */
439 		err = mmc_send_csd(card, card->raw_csd);
440 		if (err)
441 			goto free_card;
442 
443 		err = mmc_decode_csd(card);
444 		if (err)
445 			goto free_card;
446 		err = mmc_decode_cid(card);
447 		if (err)
448 			goto free_card;
449 	}
450 
451 	/*
452 	 * Select card, as all following commands rely on that.
453 	 */
454 	if (!mmc_host_is_spi(host)) {
455 		err = mmc_select_card(card);
456 		if (err)
457 			goto free_card;
458 	}
459 
460 	if (!oldcard) {
461 		/*
462 		 * Fetch and process extended CSD.
463 		 */
464 		err = mmc_read_ext_csd(card);
465 		if (err)
466 			goto free_card;
467 		/* Erase size depends on CSD and Extended CSD */
468 		mmc_set_erase_size(card);
469 	}
470 
471 	/*
472 	 * Activate high speed (if supported)
473 	 */
474 	if ((card->ext_csd.hs_max_dtr != 0) &&
475 		(host->caps & MMC_CAP_MMC_HIGHSPEED)) {
476 		err = mmc_switch(card, EXT_CSD_CMD_SET_NORMAL,
477 			EXT_CSD_HS_TIMING, 1);
478 		if (err && err != -EBADMSG)
479 			goto free_card;
480 
481 		if (err) {
482 			printk(KERN_WARNING "%s: switch to highspeed failed\n",
483 			       mmc_hostname(card->host));
484 			err = 0;
485 		} else {
486 			mmc_card_set_highspeed(card);
487 			mmc_set_timing(card->host, MMC_TIMING_MMC_HS);
488 		}
489 	}
490 
491 	/*
492 	 * Compute bus speed.
493 	 */
494 	max_dtr = (unsigned int)-1;
495 
496 	if (mmc_card_highspeed(card)) {
497 		if (max_dtr > card->ext_csd.hs_max_dtr)
498 			max_dtr = card->ext_csd.hs_max_dtr;
499 	} else if (max_dtr > card->csd.max_dtr) {
500 		max_dtr = card->csd.max_dtr;
501 	}
502 
503 	mmc_set_clock(host, max_dtr);
504 
505 	/*
506 	 * Activate wide bus (if supported).
507 	 */
508 	if ((card->csd.mmca_vsn >= CSD_SPEC_VER_4) &&
509 	    (host->caps & (MMC_CAP_4_BIT_DATA | MMC_CAP_8_BIT_DATA))) {
510 		unsigned ext_csd_bit, bus_width;
511 
512 		if (host->caps & MMC_CAP_8_BIT_DATA) {
513 			ext_csd_bit = EXT_CSD_BUS_WIDTH_8;
514 			bus_width = MMC_BUS_WIDTH_8;
515 		} else {
516 			ext_csd_bit = EXT_CSD_BUS_WIDTH_4;
517 			bus_width = MMC_BUS_WIDTH_4;
518 		}
519 
520 		err = mmc_switch(card, EXT_CSD_CMD_SET_NORMAL,
521 				 EXT_CSD_BUS_WIDTH, ext_csd_bit);
522 
523 		if (err && err != -EBADMSG)
524 			goto free_card;
525 
526 		if (err) {
527 			printk(KERN_WARNING "%s: switch to bus width %d "
528 			       "failed\n", mmc_hostname(card->host),
529 			       1 << bus_width);
530 			err = 0;
531 		} else {
532 			mmc_set_bus_width(card->host, bus_width);
533 		}
534 	}
535 
536 	if (!oldcard)
537 		host->card = card;
538 
539 	return 0;
540 
541 free_card:
542 	if (!oldcard)
543 		mmc_remove_card(card);
544 err:
545 
546 	return err;
547 }
548 
549 /*
550  * Host is being removed. Free up the current card.
551  */
552 static void mmc_remove(struct mmc_host *host)
553 {
554 	BUG_ON(!host);
555 	BUG_ON(!host->card);
556 
557 	mmc_remove_card(host->card);
558 	host->card = NULL;
559 }
560 
561 /*
562  * Card detection callback from host.
563  */
564 static void mmc_detect(struct mmc_host *host)
565 {
566 	int err;
567 
568 	BUG_ON(!host);
569 	BUG_ON(!host->card);
570 
571 	mmc_claim_host(host);
572 
573 	/*
574 	 * Just check if our card has been removed.
575 	 */
576 	err = mmc_send_status(host->card, NULL);
577 
578 	mmc_release_host(host);
579 
580 	if (err) {
581 		mmc_remove(host);
582 
583 		mmc_claim_host(host);
584 		mmc_detach_bus(host);
585 		mmc_release_host(host);
586 	}
587 }
588 
589 /*
590  * Suspend callback from host.
591  */
592 static int mmc_suspend(struct mmc_host *host)
593 {
594 	BUG_ON(!host);
595 	BUG_ON(!host->card);
596 
597 	mmc_claim_host(host);
598 	if (!mmc_host_is_spi(host))
599 		mmc_deselect_cards(host);
600 	host->card->state &= ~MMC_STATE_HIGHSPEED;
601 	mmc_release_host(host);
602 
603 	return 0;
604 }
605 
606 /*
607  * Resume callback from host.
608  *
609  * This function tries to determine if the same card is still present
610  * and, if so, restore all state to it.
611  */
612 static int mmc_resume(struct mmc_host *host)
613 {
614 	int err;
615 
616 	BUG_ON(!host);
617 	BUG_ON(!host->card);
618 
619 	mmc_claim_host(host);
620 	err = mmc_init_card(host, host->ocr, host->card);
621 	mmc_release_host(host);
622 
623 	return err;
624 }
625 
626 static void mmc_power_restore(struct mmc_host *host)
627 {
628 	host->card->state &= ~MMC_STATE_HIGHSPEED;
629 	mmc_claim_host(host);
630 	mmc_init_card(host, host->ocr, host->card);
631 	mmc_release_host(host);
632 }
633 
634 static int mmc_sleep(struct mmc_host *host)
635 {
636 	struct mmc_card *card = host->card;
637 	int err = -ENOSYS;
638 
639 	if (card && card->ext_csd.rev >= 3) {
640 		err = mmc_card_sleepawake(host, 1);
641 		if (err < 0)
642 			pr_debug("%s: Error %d while putting card into sleep",
643 				 mmc_hostname(host), err);
644 	}
645 
646 	return err;
647 }
648 
649 static int mmc_awake(struct mmc_host *host)
650 {
651 	struct mmc_card *card = host->card;
652 	int err = -ENOSYS;
653 
654 	if (card && card->ext_csd.rev >= 3) {
655 		err = mmc_card_sleepawake(host, 0);
656 		if (err < 0)
657 			pr_debug("%s: Error %d while awaking sleeping card",
658 				 mmc_hostname(host), err);
659 	}
660 
661 	return err;
662 }
663 
664 static const struct mmc_bus_ops mmc_ops = {
665 	.awake = mmc_awake,
666 	.sleep = mmc_sleep,
667 	.remove = mmc_remove,
668 	.detect = mmc_detect,
669 	.suspend = NULL,
670 	.resume = NULL,
671 	.power_restore = mmc_power_restore,
672 };
673 
674 static const struct mmc_bus_ops mmc_ops_unsafe = {
675 	.awake = mmc_awake,
676 	.sleep = mmc_sleep,
677 	.remove = mmc_remove,
678 	.detect = mmc_detect,
679 	.suspend = mmc_suspend,
680 	.resume = mmc_resume,
681 	.power_restore = mmc_power_restore,
682 };
683 
684 static void mmc_attach_bus_ops(struct mmc_host *host)
685 {
686 	const struct mmc_bus_ops *bus_ops;
687 
688 	if (host->caps & MMC_CAP_NONREMOVABLE || !mmc_assume_removable)
689 		bus_ops = &mmc_ops_unsafe;
690 	else
691 		bus_ops = &mmc_ops;
692 	mmc_attach_bus(host, bus_ops);
693 }
694 
695 /*
696  * Starting point for MMC card init.
697  */
698 int mmc_attach_mmc(struct mmc_host *host, u32 ocr)
699 {
700 	int err;
701 
702 	BUG_ON(!host);
703 	WARN_ON(!host->claimed);
704 
705 	mmc_attach_bus_ops(host);
706 
707 	/*
708 	 * We need to get OCR a different way for SPI.
709 	 */
710 	if (mmc_host_is_spi(host)) {
711 		err = mmc_spi_read_ocr(host, 1, &ocr);
712 		if (err)
713 			goto err;
714 	}
715 
716 	/*
717 	 * Sanity check the voltages that the card claims to
718 	 * support.
719 	 */
720 	if (ocr & 0x7F) {
721 		printk(KERN_WARNING "%s: card claims to support voltages "
722 		       "below the defined range. These will be ignored.\n",
723 		       mmc_hostname(host));
724 		ocr &= ~0x7F;
725 	}
726 
727 	host->ocr = mmc_select_voltage(host, ocr);
728 
729 	/*
730 	 * Can we support the voltage of the card?
731 	 */
732 	if (!host->ocr) {
733 		err = -EINVAL;
734 		goto err;
735 	}
736 
737 	/*
738 	 * Detect and init the card.
739 	 */
740 	err = mmc_init_card(host, host->ocr, NULL);
741 	if (err)
742 		goto err;
743 
744 	mmc_release_host(host);
745 
746 	err = mmc_add_card(host->card);
747 	if (err)
748 		goto remove_card;
749 
750 	return 0;
751 
752 remove_card:
753 	mmc_remove_card(host->card);
754 	host->card = NULL;
755 	mmc_claim_host(host);
756 err:
757 	mmc_detach_bus(host);
758 	mmc_release_host(host);
759 
760 	printk(KERN_ERR "%s: error %d whilst initialising MMC card\n",
761 		mmc_hostname(host), err);
762 
763 	return err;
764 }
765