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.h"
25 #include "sd_ops.h"
26 
27 static const unsigned int tran_exp[] = {
28 	10000,		100000,		1000000,	10000000,
29 	0,		0,		0,		0
30 };
31 
32 static const unsigned char tran_mant[] = {
33 	0,	10,	12,	13,	15,	20,	25,	30,
34 	35,	40,	45,	50,	55,	60,	70,	80,
35 };
36 
37 static const unsigned int tacc_exp[] = {
38 	1,	10,	100,	1000,	10000,	100000,	1000000, 10000000,
39 };
40 
41 static const unsigned int tacc_mant[] = {
42 	0,	10,	12,	13,	15,	20,	25,	30,
43 	35,	40,	45,	50,	55,	60,	70,	80,
44 };
45 
46 #define UNSTUFF_BITS(resp,start,size)					\
47 	({								\
48 		const int __size = size;				\
49 		const u32 __mask = (__size < 32 ? 1 << __size : 0) - 1;	\
50 		const int __off = 3 - ((start) / 32);			\
51 		const int __shft = (start) & 31;			\
52 		u32 __res;						\
53 									\
54 		__res = resp[__off] >> __shft;				\
55 		if (__size + __shft > 32)				\
56 			__res |= resp[__off-1] << ((32 - __shft) % 32);	\
57 		__res & __mask;						\
58 	})
59 
60 /*
61  * Given the decoded CSD structure, decode the raw CID to our CID structure.
62  */
mmc_decode_cid(struct mmc_card * card)63 void mmc_decode_cid(struct mmc_card *card)
64 {
65 	u32 *resp = card->raw_cid;
66 
67 	memset(&card->cid, 0, sizeof(struct mmc_cid));
68 
69 	/*
70 	 * SD doesn't currently have a version field so we will
71 	 * have to assume we can parse this.
72 	 */
73 	card->cid.manfid		= UNSTUFF_BITS(resp, 120, 8);
74 	card->cid.oemid			= UNSTUFF_BITS(resp, 104, 16);
75 	card->cid.prod_name[0]		= UNSTUFF_BITS(resp, 96, 8);
76 	card->cid.prod_name[1]		= UNSTUFF_BITS(resp, 88, 8);
77 	card->cid.prod_name[2]		= UNSTUFF_BITS(resp, 80, 8);
78 	card->cid.prod_name[3]		= UNSTUFF_BITS(resp, 72, 8);
79 	card->cid.prod_name[4]		= UNSTUFF_BITS(resp, 64, 8);
80 	card->cid.hwrev			= UNSTUFF_BITS(resp, 60, 4);
81 	card->cid.fwrev			= UNSTUFF_BITS(resp, 56, 4);
82 	card->cid.serial		= UNSTUFF_BITS(resp, 24, 32);
83 	card->cid.year			= UNSTUFF_BITS(resp, 12, 8);
84 	card->cid.month			= UNSTUFF_BITS(resp, 8, 4);
85 
86 	card->cid.year += 2000; /* SD cards year offset */
87 }
88 
89 /*
90  * Given a 128-bit response, decode to our card CSD structure.
91  */
mmc_decode_csd(struct mmc_card * card)92 static int mmc_decode_csd(struct mmc_card *card)
93 {
94 	struct mmc_csd *csd = &card->csd;
95 	unsigned int e, m, csd_struct;
96 	u32 *resp = card->raw_csd;
97 
98 	csd_struct = UNSTUFF_BITS(resp, 126, 2);
99 
100 	switch (csd_struct) {
101 	case 0:
102 		m = UNSTUFF_BITS(resp, 115, 4);
103 		e = UNSTUFF_BITS(resp, 112, 3);
104 		csd->tacc_ns	 = (tacc_exp[e] * tacc_mant[m] + 9) / 10;
105 		csd->tacc_clks	 = UNSTUFF_BITS(resp, 104, 8) * 100;
106 
107 		m = UNSTUFF_BITS(resp, 99, 4);
108 		e = UNSTUFF_BITS(resp, 96, 3);
109 		csd->max_dtr	  = tran_exp[e] * tran_mant[m];
110 		csd->cmdclass	  = UNSTUFF_BITS(resp, 84, 12);
111 
112 		e = UNSTUFF_BITS(resp, 47, 3);
113 		m = UNSTUFF_BITS(resp, 62, 12);
114 		csd->capacity	  = (1 + m) << (e + 2);
115 
116 		csd->read_blkbits = UNSTUFF_BITS(resp, 80, 4);
117 		csd->read_partial = UNSTUFF_BITS(resp, 79, 1);
118 		csd->write_misalign = UNSTUFF_BITS(resp, 78, 1);
119 		csd->read_misalign = UNSTUFF_BITS(resp, 77, 1);
120 		csd->r2w_factor = UNSTUFF_BITS(resp, 26, 3);
121 		csd->write_blkbits = UNSTUFF_BITS(resp, 22, 4);
122 		csd->write_partial = UNSTUFF_BITS(resp, 21, 1);
123 
124 		if (UNSTUFF_BITS(resp, 46, 1)) {
125 			csd->erase_size = 1;
126 		} else if (csd->write_blkbits >= 9) {
127 			csd->erase_size = UNSTUFF_BITS(resp, 39, 7) + 1;
128 			csd->erase_size <<= csd->write_blkbits - 9;
129 		}
130 		break;
131 	case 1:
132 		/*
133 		 * This is a block-addressed SDHC card. Most
134 		 * interesting fields are unused and have fixed
135 		 * values. To avoid getting tripped by buggy cards,
136 		 * we assume those fixed values ourselves.
137 		 */
138 		mmc_card_set_blockaddr(card);
139 
140 		csd->tacc_ns	 = 0; /* Unused */
141 		csd->tacc_clks	 = 0; /* Unused */
142 
143 		m = UNSTUFF_BITS(resp, 99, 4);
144 		e = UNSTUFF_BITS(resp, 96, 3);
145 		csd->max_dtr	  = tran_exp[e] * tran_mant[m];
146 		csd->cmdclass	  = UNSTUFF_BITS(resp, 84, 12);
147 
148 		m = UNSTUFF_BITS(resp, 48, 22);
149 		csd->capacity     = (1 + m) << 10;
150 
151 		csd->read_blkbits = 9;
152 		csd->read_partial = 0;
153 		csd->write_misalign = 0;
154 		csd->read_misalign = 0;
155 		csd->r2w_factor = 4; /* Unused */
156 		csd->write_blkbits = 9;
157 		csd->write_partial = 0;
158 		csd->erase_size = 1;
159 		break;
160 	default:
161 		printk(KERN_ERR "%s: unrecognised CSD structure version %d\n",
162 			mmc_hostname(card->host), csd_struct);
163 		return -EINVAL;
164 	}
165 
166 	card->erase_size = csd->erase_size;
167 
168 	return 0;
169 }
170 
171 /*
172  * Given a 64-bit response, decode to our card SCR structure.
173  */
mmc_decode_scr(struct mmc_card * card)174 static int mmc_decode_scr(struct mmc_card *card)
175 {
176 	struct sd_scr *scr = &card->scr;
177 	unsigned int scr_struct;
178 	u32 resp[4];
179 
180 	resp[3] = card->raw_scr[1];
181 	resp[2] = card->raw_scr[0];
182 
183 	scr_struct = UNSTUFF_BITS(resp, 60, 4);
184 	if (scr_struct != 0) {
185 		printk(KERN_ERR "%s: unrecognised SCR structure version %d\n",
186 			mmc_hostname(card->host), scr_struct);
187 		return -EINVAL;
188 	}
189 
190 	scr->sda_vsn = UNSTUFF_BITS(resp, 56, 4);
191 	scr->bus_widths = UNSTUFF_BITS(resp, 48, 4);
192 
193 	if (UNSTUFF_BITS(resp, 55, 1))
194 		card->erased_byte = 0xFF;
195 	else
196 		card->erased_byte = 0x0;
197 
198 	return 0;
199 }
200 
201 /*
202  * Fetch and process SD Status register.
203  */
mmc_read_ssr(struct mmc_card * card)204 static int mmc_read_ssr(struct mmc_card *card)
205 {
206 	unsigned int au, es, et, eo;
207 	int err, i;
208 	u32 *ssr;
209 
210 	if (!(card->csd.cmdclass & CCC_APP_SPEC)) {
211 		printk(KERN_WARNING "%s: card lacks mandatory SD Status "
212 			"function.\n", mmc_hostname(card->host));
213 		return 0;
214 	}
215 
216 	ssr = kmalloc(64, GFP_KERNEL);
217 	if (!ssr)
218 		return -ENOMEM;
219 
220 	err = mmc_app_sd_status(card, ssr);
221 	if (err) {
222 		printk(KERN_WARNING "%s: problem reading SD Status "
223 			"register.\n", mmc_hostname(card->host));
224 		err = 0;
225 		goto out;
226 	}
227 
228 	for (i = 0; i < 16; i++)
229 		ssr[i] = be32_to_cpu(ssr[i]);
230 
231 	/*
232 	 * UNSTUFF_BITS only works with four u32s so we have to offset the
233 	 * bitfield positions accordingly.
234 	 */
235 	au = UNSTUFF_BITS(ssr, 428 - 384, 4);
236 	if (au > 0 || au <= 9) {
237 		card->ssr.au = 1 << (au + 4);
238 		es = UNSTUFF_BITS(ssr, 408 - 384, 16);
239 		et = UNSTUFF_BITS(ssr, 402 - 384, 6);
240 		eo = UNSTUFF_BITS(ssr, 400 - 384, 2);
241 		if (es && et) {
242 			card->ssr.erase_timeout = (et * 1000) / es;
243 			card->ssr.erase_offset = eo * 1000;
244 		}
245 	} else {
246 		printk(KERN_WARNING "%s: SD Status: Invalid Allocation Unit "
247 			"size.\n", mmc_hostname(card->host));
248 	}
249 out:
250 	kfree(ssr);
251 	return err;
252 }
253 
254 /*
255  * Fetches and decodes switch information
256  */
mmc_read_switch(struct mmc_card * card)257 static int mmc_read_switch(struct mmc_card *card)
258 {
259 	int err;
260 	u8 *status;
261 
262 	if (card->scr.sda_vsn < SCR_SPEC_VER_1)
263 		return 0;
264 
265 	if (!(card->csd.cmdclass & CCC_SWITCH)) {
266 		printk(KERN_WARNING "%s: card lacks mandatory switch "
267 			"function, performance might suffer.\n",
268 			mmc_hostname(card->host));
269 		return 0;
270 	}
271 
272 	err = -EIO;
273 
274 	status = kmalloc(64, GFP_KERNEL);
275 	if (!status) {
276 		printk(KERN_ERR "%s: could not allocate a buffer for "
277 			"switch capabilities.\n", mmc_hostname(card->host));
278 		return -ENOMEM;
279 	}
280 
281 	err = mmc_sd_switch(card, 0, 0, 1, status);
282 	if (err) {
283 		/* If the host or the card can't do the switch,
284 		 * fail more gracefully. */
285 		if ((err != -EINVAL)
286 		 && (err != -ENOSYS)
287 		 && (err != -EFAULT))
288 			goto out;
289 
290 		printk(KERN_WARNING "%s: problem reading switch "
291 			"capabilities, performance might suffer.\n",
292 			mmc_hostname(card->host));
293 		err = 0;
294 
295 		goto out;
296 	}
297 
298 	if (status[13] & 0x02)
299 		card->sw_caps.hs_max_dtr = 50000000;
300 
301 out:
302 	kfree(status);
303 
304 	return err;
305 }
306 
307 /*
308  * Test if the card supports high-speed mode and, if so, switch to it.
309  */
mmc_sd_switch_hs(struct mmc_card * card)310 int mmc_sd_switch_hs(struct mmc_card *card)
311 {
312 	int err;
313 	u8 *status;
314 
315 	if (card->scr.sda_vsn < SCR_SPEC_VER_1)
316 		return 0;
317 
318 	if (!(card->csd.cmdclass & CCC_SWITCH))
319 		return 0;
320 
321 	if (!(card->host->caps & MMC_CAP_SD_HIGHSPEED))
322 		return 0;
323 
324 	if (card->sw_caps.hs_max_dtr == 0)
325 		return 0;
326 
327 	err = -EIO;
328 
329 	status = kmalloc(64, GFP_KERNEL);
330 	if (!status) {
331 		printk(KERN_ERR "%s: could not allocate a buffer for "
332 			"switch capabilities.\n", mmc_hostname(card->host));
333 		return -ENOMEM;
334 	}
335 
336 	err = mmc_sd_switch(card, 1, 0, 1, status);
337 	if (err)
338 		goto out;
339 
340 	if ((status[16] & 0xF) != 1) {
341 		printk(KERN_WARNING "%s: Problem switching card "
342 			"into high-speed mode!\n",
343 			mmc_hostname(card->host));
344 		err = 0;
345 	} else {
346 		err = 1;
347 	}
348 
349 out:
350 	kfree(status);
351 
352 	return err;
353 }
354 
355 MMC_DEV_ATTR(cid, "%08x%08x%08x%08x\n", card->raw_cid[0], card->raw_cid[1],
356 	card->raw_cid[2], card->raw_cid[3]);
357 MMC_DEV_ATTR(csd, "%08x%08x%08x%08x\n", card->raw_csd[0], card->raw_csd[1],
358 	card->raw_csd[2], card->raw_csd[3]);
359 MMC_DEV_ATTR(scr, "%08x%08x\n", card->raw_scr[0], card->raw_scr[1]);
360 MMC_DEV_ATTR(date, "%02d/%04d\n", card->cid.month, card->cid.year);
361 MMC_DEV_ATTR(erase_size, "%u\n", card->erase_size << 9);
362 MMC_DEV_ATTR(preferred_erase_size, "%u\n", card->pref_erase << 9);
363 MMC_DEV_ATTR(fwrev, "0x%x\n", card->cid.fwrev);
364 MMC_DEV_ATTR(hwrev, "0x%x\n", card->cid.hwrev);
365 MMC_DEV_ATTR(manfid, "0x%06x\n", card->cid.manfid);
366 MMC_DEV_ATTR(name, "%s\n", card->cid.prod_name);
367 MMC_DEV_ATTR(oemid, "0x%04x\n", card->cid.oemid);
368 MMC_DEV_ATTR(serial, "0x%08x\n", card->cid.serial);
369 
370 
371 static struct attribute *sd_std_attrs[] = {
372 	&dev_attr_cid.attr,
373 	&dev_attr_csd.attr,
374 	&dev_attr_scr.attr,
375 	&dev_attr_date.attr,
376 	&dev_attr_erase_size.attr,
377 	&dev_attr_preferred_erase_size.attr,
378 	&dev_attr_fwrev.attr,
379 	&dev_attr_hwrev.attr,
380 	&dev_attr_manfid.attr,
381 	&dev_attr_name.attr,
382 	&dev_attr_oemid.attr,
383 	&dev_attr_serial.attr,
384 	NULL,
385 };
386 
387 static struct attribute_group sd_std_attr_group = {
388 	.attrs = sd_std_attrs,
389 };
390 
391 static const struct attribute_group *sd_attr_groups[] = {
392 	&sd_std_attr_group,
393 	NULL,
394 };
395 
396 struct device_type sd_type = {
397 	.groups = sd_attr_groups,
398 };
399 
400 /*
401  * Fetch CID from card.
402  */
mmc_sd_get_cid(struct mmc_host * host,u32 ocr,u32 * cid)403 int mmc_sd_get_cid(struct mmc_host *host, u32 ocr, u32 *cid)
404 {
405 	int err;
406 
407 	/*
408 	 * Since we're changing the OCR value, we seem to
409 	 * need to tell some cards to go back to the idle
410 	 * state.  We wait 1ms to give cards time to
411 	 * respond.
412 	 */
413 	mmc_go_idle(host);
414 
415 	/*
416 	 * If SD_SEND_IF_COND indicates an SD 2.0
417 	 * compliant card and we should set bit 30
418 	 * of the ocr to indicate that we can handle
419 	 * block-addressed SDHC cards.
420 	 */
421 	err = mmc_send_if_cond(host, ocr);
422 	if (!err)
423 		ocr |= 1 << 30;
424 
425 	err = mmc_send_app_op_cond(host, ocr, NULL);
426 	if (err)
427 		return err;
428 
429 	if (mmc_host_is_spi(host))
430 		err = mmc_send_cid(host, cid);
431 	else
432 		err = mmc_all_send_cid(host, cid);
433 
434 	return err;
435 }
436 
mmc_sd_get_csd(struct mmc_host * host,struct mmc_card * card)437 int mmc_sd_get_csd(struct mmc_host *host, struct mmc_card *card)
438 {
439 	int err;
440 
441 	/*
442 	 * Fetch CSD from card.
443 	 */
444 	err = mmc_send_csd(card, card->raw_csd);
445 	if (err)
446 		return err;
447 
448 	err = mmc_decode_csd(card);
449 	if (err)
450 		return err;
451 
452 	return 0;
453 }
454 
mmc_sd_setup_card(struct mmc_host * host,struct mmc_card * card,bool reinit)455 int mmc_sd_setup_card(struct mmc_host *host, struct mmc_card *card,
456 	bool reinit)
457 {
458 	int err;
459 
460 	if (!reinit) {
461 		/*
462 		 * Fetch SCR from card.
463 		 */
464 		err = mmc_app_send_scr(card, card->raw_scr);
465 		if (err)
466 			return err;
467 
468 		err = mmc_decode_scr(card);
469 		if (err)
470 			return err;
471 
472 		/*
473 		 * Fetch and process SD Status register.
474 		 */
475 		err = mmc_read_ssr(card);
476 		if (err)
477 			return err;
478 
479 		/* Erase init depends on CSD and SSR */
480 		mmc_init_erase(card);
481 
482 		/*
483 		 * Fetch switch information from card.
484 		 */
485 		err = mmc_read_switch(card);
486 		if (err)
487 			return err;
488 	}
489 
490 	/*
491 	 * For SPI, enable CRC as appropriate.
492 	 * This CRC enable is located AFTER the reading of the
493 	 * card registers because some SDHC cards are not able
494 	 * to provide valid CRCs for non-512-byte blocks.
495 	 */
496 	if (mmc_host_is_spi(host)) {
497 		err = mmc_spi_set_crc(host, use_spi_crc);
498 		if (err)
499 			return err;
500 	}
501 
502 	/*
503 	 * Check if read-only switch is active.
504 	 */
505 	if (!reinit) {
506 		int ro = -1;
507 
508 		if (host->ops->get_ro)
509 			ro = host->ops->get_ro(host);
510 
511 		if (ro < 0) {
512 			printk(KERN_WARNING "%s: host does not "
513 				"support reading read-only "
514 				"switch. assuming write-enable.\n",
515 				mmc_hostname(host));
516 		} else if (ro > 0) {
517 			mmc_card_set_readonly(card);
518 		}
519 	}
520 
521 	return 0;
522 }
523 
mmc_sd_get_max_clock(struct mmc_card * card)524 unsigned mmc_sd_get_max_clock(struct mmc_card *card)
525 {
526 	unsigned max_dtr = (unsigned int)-1;
527 
528 	if (mmc_card_highspeed(card)) {
529 		if (max_dtr > card->sw_caps.hs_max_dtr)
530 			max_dtr = card->sw_caps.hs_max_dtr;
531 	} else if (max_dtr > card->csd.max_dtr) {
532 		max_dtr = card->csd.max_dtr;
533 	}
534 
535 	return max_dtr;
536 }
537 
mmc_sd_go_highspeed(struct mmc_card * card)538 void mmc_sd_go_highspeed(struct mmc_card *card)
539 {
540 	mmc_card_set_highspeed(card);
541 	mmc_set_timing(card->host, MMC_TIMING_SD_HS);
542 }
543 
544 /*
545  * Handle the detection and initialisation of a card.
546  *
547  * In the case of a resume, "oldcard" will contain the card
548  * we're trying to reinitialise.
549  */
mmc_sd_init_card(struct mmc_host * host,u32 ocr,struct mmc_card * oldcard)550 static int mmc_sd_init_card(struct mmc_host *host, u32 ocr,
551 	struct mmc_card *oldcard)
552 {
553 	struct mmc_card *card;
554 	int err;
555 	u32 cid[4];
556 
557 	BUG_ON(!host);
558 	WARN_ON(!host->claimed);
559 
560 	err = mmc_sd_get_cid(host, ocr, cid);
561 	if (err)
562 		return err;
563 
564 	if (oldcard) {
565 		if (memcmp(cid, oldcard->raw_cid, sizeof(cid)) != 0)
566 			return -ENOENT;
567 
568 		card = oldcard;
569 	} else {
570 		/*
571 		 * Allocate card structure.
572 		 */
573 		card = mmc_alloc_card(host, &sd_type);
574 		if (IS_ERR(card))
575 			return PTR_ERR(card);
576 
577 		card->type = MMC_TYPE_SD;
578 		memcpy(card->raw_cid, cid, sizeof(card->raw_cid));
579 	}
580 
581 	/*
582 	 * For native busses:  get card RCA and quit open drain mode.
583 	 */
584 	if (!mmc_host_is_spi(host)) {
585 		err = mmc_send_relative_addr(host, &card->rca);
586 		if (err)
587 			return err;
588 
589 		mmc_set_bus_mode(host, MMC_BUSMODE_PUSHPULL);
590 	}
591 
592 	if (!oldcard) {
593 		err = mmc_sd_get_csd(host, card);
594 		if (err)
595 			return err;
596 
597 		mmc_decode_cid(card);
598 	}
599 
600 	/*
601 	 * Select card, as all following commands rely on that.
602 	 */
603 	if (!mmc_host_is_spi(host)) {
604 		err = mmc_select_card(card);
605 		if (err)
606 			return err;
607 	}
608 
609 	err = mmc_sd_setup_card(host, card, oldcard != NULL);
610 	if (err)
611 		goto free_card;
612 
613 	/*
614 	 * Attempt to change to high-speed (if supported)
615 	 */
616 	err = mmc_sd_switch_hs(card);
617 	if (err > 0)
618 		mmc_sd_go_highspeed(card);
619 	else if (err)
620 		goto free_card;
621 
622 	/*
623 	 * Set bus speed.
624 	 */
625 	mmc_set_clock(host, mmc_sd_get_max_clock(card));
626 
627 	/*
628 	 * Switch to wider bus (if supported).
629 	 */
630 	if ((host->caps & MMC_CAP_4_BIT_DATA) &&
631 		(card->scr.bus_widths & SD_SCR_BUS_WIDTH_4)) {
632 		err = mmc_app_set_bus_width(card, MMC_BUS_WIDTH_4);
633 		if (err)
634 			goto free_card;
635 
636 		mmc_set_bus_width(host, MMC_BUS_WIDTH_4);
637 	}
638 
639 	host->card = card;
640 	return 0;
641 
642 free_card:
643 	if (!oldcard)
644 		mmc_remove_card(card);
645 
646 	return err;
647 }
648 
649 /*
650  * Host is being removed. Free up the current card.
651  */
mmc_sd_remove(struct mmc_host * host)652 static void mmc_sd_remove(struct mmc_host *host)
653 {
654 	BUG_ON(!host);
655 	BUG_ON(!host->card);
656 
657 	mmc_remove_card(host->card);
658 	host->card = NULL;
659 }
660 
661 /*
662  * Card detection callback from host.
663  */
mmc_sd_detect(struct mmc_host * host)664 static void mmc_sd_detect(struct mmc_host *host)
665 {
666 	int err;
667 
668 	BUG_ON(!host);
669 	BUG_ON(!host->card);
670 
671 	mmc_claim_host(host);
672 
673 	/*
674 	 * Just check if our card has been removed.
675 	 */
676 	err = mmc_send_status(host->card, NULL);
677 
678 	mmc_release_host(host);
679 
680 	if (err) {
681 		mmc_sd_remove(host);
682 
683 		mmc_claim_host(host);
684 		mmc_detach_bus(host);
685 		mmc_release_host(host);
686 	}
687 }
688 
689 /*
690  * Suspend callback from host.
691  */
mmc_sd_suspend(struct mmc_host * host)692 static int mmc_sd_suspend(struct mmc_host *host)
693 {
694 	BUG_ON(!host);
695 	BUG_ON(!host->card);
696 
697 	mmc_claim_host(host);
698 	if (!mmc_host_is_spi(host))
699 		mmc_deselect_cards(host);
700 	host->card->state &= ~MMC_STATE_HIGHSPEED;
701 	mmc_release_host(host);
702 
703 	return 0;
704 }
705 
706 /*
707  * Resume callback from host.
708  *
709  * This function tries to determine if the same card is still present
710  * and, if so, restore all state to it.
711  */
mmc_sd_resume(struct mmc_host * host)712 static int mmc_sd_resume(struct mmc_host *host)
713 {
714 	int err;
715 
716 	BUG_ON(!host);
717 	BUG_ON(!host->card);
718 
719 	mmc_claim_host(host);
720 	err = mmc_sd_init_card(host, host->ocr, host->card);
721 	mmc_release_host(host);
722 
723 	return err;
724 }
725 
mmc_sd_power_restore(struct mmc_host * host)726 static int mmc_sd_power_restore(struct mmc_host *host)
727 {
728 	int ret;
729 
730 	host->card->state &= ~MMC_STATE_HIGHSPEED;
731 	mmc_claim_host(host);
732 	ret = mmc_sd_init_card(host, host->ocr, host->card);
733 	mmc_release_host(host);
734 
735 	return ret;
736 }
737 
738 static const struct mmc_bus_ops mmc_sd_ops = {
739 	.remove = mmc_sd_remove,
740 	.detect = mmc_sd_detect,
741 	.suspend = NULL,
742 	.resume = NULL,
743 	.power_restore = mmc_sd_power_restore,
744 };
745 
746 static const struct mmc_bus_ops mmc_sd_ops_unsafe = {
747 	.remove = mmc_sd_remove,
748 	.detect = mmc_sd_detect,
749 	.suspend = mmc_sd_suspend,
750 	.resume = mmc_sd_resume,
751 	.power_restore = mmc_sd_power_restore,
752 };
753 
mmc_sd_attach_bus_ops(struct mmc_host * host)754 static void mmc_sd_attach_bus_ops(struct mmc_host *host)
755 {
756 	const struct mmc_bus_ops *bus_ops;
757 
758 	if (!mmc_card_is_removable(host))
759 		bus_ops = &mmc_sd_ops_unsafe;
760 	else
761 		bus_ops = &mmc_sd_ops;
762 	mmc_attach_bus(host, bus_ops);
763 }
764 
765 /*
766  * Starting point for SD card init.
767  */
mmc_attach_sd(struct mmc_host * host)768 int mmc_attach_sd(struct mmc_host *host)
769 {
770 	int err;
771 	u32 ocr;
772 
773 	BUG_ON(!host);
774 	WARN_ON(!host->claimed);
775 
776 	err = mmc_send_app_op_cond(host, 0, &ocr);
777 	if (err)
778 		return err;
779 
780 	mmc_sd_attach_bus_ops(host);
781 	if (host->ocr_avail_sd)
782 		host->ocr_avail = host->ocr_avail_sd;
783 
784 	/*
785 	 * We need to get OCR a different way for SPI.
786 	 */
787 	if (mmc_host_is_spi(host)) {
788 		mmc_go_idle(host);
789 
790 		err = mmc_spi_read_ocr(host, 0, &ocr);
791 		if (err)
792 			goto err;
793 	}
794 
795 	/*
796 	 * Sanity check the voltages that the card claims to
797 	 * support.
798 	 */
799 	if (ocr & 0x7F) {
800 		printk(KERN_WARNING "%s: card claims to support voltages "
801 		       "below the defined range. These will be ignored.\n",
802 		       mmc_hostname(host));
803 		ocr &= ~0x7F;
804 	}
805 
806 	if ((ocr & MMC_VDD_165_195) &&
807 	    !(host->ocr_avail_sd & MMC_VDD_165_195)) {
808 		printk(KERN_WARNING "%s: SD card claims to support the "
809 		       "incompletely defined 'low voltage range'. This "
810 		       "will be ignored.\n", mmc_hostname(host));
811 		ocr &= ~MMC_VDD_165_195;
812 	}
813 
814 	host->ocr = mmc_select_voltage(host, ocr);
815 
816 	/*
817 	 * Can we support the voltage(s) of the card(s)?
818 	 */
819 	if (!host->ocr) {
820 		err = -EINVAL;
821 		goto err;
822 	}
823 
824 	/*
825 	 * Detect and init the card.
826 	 */
827 	err = mmc_sd_init_card(host, host->ocr, NULL);
828 	if (err)
829 		goto err;
830 
831 	mmc_release_host(host);
832 	err = mmc_add_card(host->card);
833 	mmc_claim_host(host);
834 	if (err)
835 		goto remove_card;
836 
837 	return 0;
838 
839 remove_card:
840 	mmc_release_host(host);
841 	mmc_remove_card(host->card);
842 	host->card = NULL;
843 	mmc_claim_host(host);
844 err:
845 	mmc_detach_bus(host);
846 
847 	printk(KERN_ERR "%s: error %d whilst initialising SD card\n",
848 		mmc_hostname(host), err);
849 
850 	return err;
851 }
852 
853