xref: /openbmc/linux/drivers/mmc/core/sd.c (revision 4800cd83)
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 
852