aboutsummaryrefslogtreecommitdiffstats
path: root/drivers/mmc/core/mmc.c
blob: 66f85bfa8dbbfb9704df09c68245d3d137339275 (plain) (blame)
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
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
92
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
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
202
203
204
205
206
207
208
209
210
211
212
213
214
215
216
217
218
219
220
221
222
223
224
225
226
227
228
229
230
231
232
233
234
235
236
237
238
239
240
241
242
243
244
245
246
247
248
249
250
251
252
253
254
255
256
257
258
259
260
261
262
263
264
265
266
267
268
269
270
271
272
273
274
275
276
277
278
279
280
281
282
283
284
285
286
287
288
289
290
291
292
293
294
295
296
297
298
299
300
301
302
303
304
305
306
307
308
309
310
311
312
313
314
315
316
317
318
319
320
321
322
323
324
325
326
327
328
329
330
331
332
333
334
335
336
337
338
339
340
341
342
343
344
345
346
347
348
349
350
351
352
353
354
355
356
357
358
359
360
361
362
363
364
365
366
367
368
369
370
371
372
373
374
375
376
377
378
379
380
381
382
383
384
385
386
387
388
389
390
391
392
393
394
395
396
397
398
399
400
401
402
403
404
405
406
407
408
409
410
411
412
413
414
415
416
417
418
419
420
421
422
423
424
425
426
427
428
429
430
431
432
433
434
435
436
437
438
439
440
441
442
443
444
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
486
487
488
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
/*
 *  linux/drivers/mmc/mmc.c
 *
 *  Copyright (C) 2003-2004 Russell King, All Rights Reserved.
 *  Copyright (C) 2005-2007 Pierre Ossman, All Rights Reserved.
 *  MMCv4 support Copyright (C) 2006 Philip Langdale, 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>

#include "core.h"
#include "sysfs.h"
#include "bus.h"
#include "mmc_ops.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 int mmc_decode_cid(struct mmc_card *card)
{
	u32 *resp = card->raw_cid;

	/*
	 * The selection of the format here is based upon published
	 * specs from sandisk and from what people have reported.
	 */
	switch (card->csd.mmca_vsn) {
	case 0: /* MMC v1.0 - v1.2 */
	case 1: /* MMC v1.4 */
		card->cid.manfid	= UNSTUFF_BITS(resp, 104, 24);
		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.prod_name[5]	= UNSTUFF_BITS(resp, 56, 8);
		card->cid.prod_name[6]	= UNSTUFF_BITS(resp, 48, 8);
		card->cid.hwrev		= UNSTUFF_BITS(resp, 44, 4);
		card->cid.fwrev		= UNSTUFF_BITS(resp, 40, 4);
		card->cid.serial	= UNSTUFF_BITS(resp, 16, 24);
		card->cid.month		= UNSTUFF_BITS(resp, 12, 4);
		card->cid.year		= UNSTUFF_BITS(resp, 8, 4) + 1997;
		break;

	case 2: /* MMC v2.0 - v2.2 */
	case 3: /* MMC v3.1 - v3.3 */
	case 4: /* MMC v4 */
		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.prod_name[5]	= UNSTUFF_BITS(resp, 56, 8);
		card->cid.serial	= UNSTUFF_BITS(resp, 16, 32);
		card->cid.month		= UNSTUFF_BITS(resp, 12, 4);
		card->cid.year		= UNSTUFF_BITS(resp, 8, 4) + 1997;
		break;

	default:
		printk("%s: card has unknown MMCA version %d\n",
			mmc_hostname(card->host), card->csd.mmca_vsn);
		return -EINVAL;
	}

	return 0;
}

/*
 * Given a 128-bit response, decode to our card CSD structure.
 */
static int mmc_decode_csd(struct mmc_card *card)
{
	struct mmc_csd *csd = &card->csd;
	unsigned int e, m, csd_struct;
	u32 *resp = card->raw_csd;

	/*
	 * We only understand CSD structure v1.1 and v1.2.
	 * v1.2 has extra information in bits 15, 11 and 10.
	 */
	csd_struct = UNSTUFF_BITS(resp, 126, 2);
	if (csd_struct != 1 && csd_struct != 2) {
		printk("%s: unrecognised CSD structure version %d\n",
			mmc_hostname(card->host), csd_struct);
		return -EINVAL;
	}

	csd->mmca_vsn	 = UNSTUFF_BITS(resp, 122, 4);
	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);

	return 0;
}

/*
 * Read and decode extended CSD.
 */
static int mmc_read_ext_csd(struct mmc_card *card)
{
	int err;
	u8 *ext_csd;

	BUG_ON(!card);

	err = MMC_ERR_FAILED;

	if (card->csd.mmca_vsn < CSD_SPEC_VER_4)
		return MMC_ERR_NONE;

	/*
	 * As the ext_csd is so large and mostly unused, we don't store the
	 * raw block in mmc_card.
	 */
	ext_csd = kmalloc(512, GFP_KERNEL);
	if (!ext_csd) {
		printk(KERN_ERR "%s: could not allocate a buffer to "
			"receive the ext_csd. mmc v4 cards will be "
			"treated as v3.\n", mmc_hostname(card->host));
		return MMC_ERR_FAILED;
	}

	err = mmc_send_ext_csd(card, ext_csd);
	if (err != MMC_ERR_NONE) {
		/*
		 * High capacity cards should have this "magic" size
		 * stored in their CSD.
		 */
		if (card->csd.capacity == (4096 * 512)) {
			printk(KERN_ERR "%s: unable to read EXT_CSD "
				"on a possible high capacity card. "
				"Card will be ignored.\n",
				mmc_hostname(card->host));
		} else {
			printk(KERN_WARNING "%s: unable to read "
				"EXT_CSD, performance might "
				"suffer.\n",
				mmc_hostname(card->host));
			err = MMC_ERR_NONE;
		}
		goto out;
	}

	card->ext_csd.sectors =
		ext_csd[EXT_CSD_SEC_CNT + 0] << 0 |
		ext_csd[EXT_CSD_SEC_CNT + 1] << 8 |
		ext_csd[EXT_CSD_SEC_CNT + 2] << 16 |
		ext_csd[EXT_CSD_SEC_CNT + 3] << 24;
	if (card->ext_csd.sectors)
		mmc_card_set_blockaddr(card);

	switch (ext_csd[EXT_CSD_CARD_TYPE]) {
	case EXT_CSD_CARD_TYPE_52 | EXT_CSD_CARD_TYPE_26:
		card->ext_csd.hs_max_dtr = 52000000;
		break;
	case EXT_CSD_CARD_TYPE_26:
		card->ext_csd.hs_max_dtr = 26000000;
		break;
	default:
		/* MMC v4 spec says this cannot happen */
		printk(KERN_WARNING "%s: card is mmc v4 but doesn't "
			"support any high-speed modes.\n",
			mmc_hostname(card->host));
		goto out;
	}

out:
	kfree(ext_csd);

	return err;
}

/*
 * Handle the detection and initialisation of a card.
 *
 * In the case of a resume, "curcard" will contain the card
 * we're trying to reinitialise.
 */
static int mmc_init_card(struct mmc_host *host, u32 ocr,
	struct mmc_card *oldcard)
{
	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);

	/* The extra bit indicates that we support high capacity */
	err = mmc_send_op_cond(host, ocr | (1 << 30), NULL);
	if (err != MMC_ERR_NONE)
		goto err;

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

	if (oldcard) {
		if (memcmp(cid, oldcard->raw_cid, sizeof(cid)) != 0)
			goto err;

		card = oldcard;
	} else {
		/*
		 * Allocate card structure.
		 */
		card = mmc_alloc_card(host);
		if (IS_ERR(card))
			goto err;

		card->type = MMC_TYPE_MMC;
		card->rca = 1;
		memcpy(card->raw_cid, cid, sizeof(card->raw_cid));
	}

	/*
	 * Set card RCA.
	 */
	err = mmc_set_relative_addr(card);
	if (err != MMC_ERR_NONE)
		goto free_card;

	mmc_set_bus_mode(host, MMC_BUSMODE_PUSHPULL);

	if (!oldcard) {
		/*
		 * Fetch CSD from card.
		 */
		err = mmc_send_csd(card, card->raw_csd);
		if (err != MMC_ERR_NONE)
			goto free_card;

		err = mmc_decode_csd(card);
		if (err < 0)
			goto free_card;
		err = mmc_decode_cid(card);
		if (err < 0)
			goto free_card;
	}

	/*
	 * Select card, as all following commands rely on that.
	 */
	err = mmc_select_card(card);
	if (err != MMC_ERR_NONE)
		goto free_card;

	if (!oldcard) {
		/*
		 * Fetch and process extened CSD.
		 */
		err = mmc_read_ext_csd(card);
		if (err != MMC_ERR_NONE)
			goto free_card;
	}

	/*
	 * Activate high speed (if supported)
	 */
	if ((card->ext_csd.hs_max_dtr != 0) &&
		(host->caps & MMC_CAP_MMC_HIGHSPEED)) {
		err = mmc_switch(card, EXT_CSD_CMD_SET_NORMAL,
			EXT_CSD_HS_TIMING, 1);
		if (err != MMC_ERR_NONE)
			goto free_card;

		mmc_card_set_highspeed(card);

		mmc_set_timing(card->host, MMC_TIMING_MMC_HS);
	}

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

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

	mmc_set_clock(host, max_dtr);

	/*
	 * Activate wide bus (if supported).
	 */
	if ((card->csd.mmca_vsn >= CSD_SPEC_VER_4) &&
		(host->caps & MMC_CAP_4_BIT_DATA)) {
		err = mmc_switch(card, EXT_CSD_CMD_SET_NORMAL,
			EXT_CSD_BUS_WIDTH, EXT_CSD_BUS_WIDTH_4);
		if (err != MMC_ERR_NONE)
			goto free_card;

		mmc_set_bus_width(card->host, MMC_BUS_WIDTH_4);
	}

	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_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_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);

	mmc_release_host(host);

	if (err != MMC_ERR_NONE) {
		mmc_remove(host);

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

MMC_ATTR_FN(cid, "%08x%08x%08x%08x\n", card->raw_cid[0], card->raw_cid[1],
	card->raw_cid[2], card->raw_cid[3]);
MMC_ATTR_FN(csd, "%08x%08x%08x%08x\n", card->raw_csd[0], card->raw_csd[1],
	card->raw_csd[2], card->raw_csd[3]);
MMC_ATTR_FN(date, "%02d/%04d\n", card->cid.month, card->cid.year);
MMC_ATTR_FN(fwrev, "0x%x\n", card->cid.fwrev);
MMC_ATTR_FN(hwrev, "0x%x\n", card->cid.hwrev);
MMC_ATTR_FN(manfid, "0x%06x\n", card->cid.manfid);
MMC_ATTR_FN(name, "%s\n", card->cid.prod_name);
MMC_ATTR_FN(oemid, "0x%04x\n", card->cid.oemid);
MMC_ATTR_FN(serial, "0x%08x\n", card->cid.serial);

static struct device_attribute mmc_dev_attrs[] = {
	MMC_ATTR_RO(cid),
	MMC_ATTR_RO(csd),
	MMC_ATTR_RO(date),
	MMC_ATTR_RO(fwrev),
	MMC_ATTR_RO(hwrev),
	MMC_ATTR_RO(manfid),
	MMC_ATTR_RO(name),
	MMC_ATTR_RO(oemid),
	MMC_ATTR_RO(serial),
	__ATTR_NULL,
};

/*
 * Adds sysfs entries as relevant.
 */
static int mmc_sysfs_add(struct mmc_host *host, struct mmc_card *card)
{
	int ret;

	ret = mmc_add_attrs(card, mmc_dev_attrs);
	if (ret < 0)
		return ret;

	return 0;
}

/*
 * Removes the sysfs entries added by mmc_sysfs_add().
 */
static void mmc_sysfs_remove(struct mmc_host *host, struct mmc_card *card)
{
	mmc_remove_attrs(card, mmc_dev_attrs);
}

#ifdef CONFIG_MMC_UNSAFE_RESUME

/*
 * Suspend callback from host.
 */
static void mmc_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_resume(struct mmc_host *host)
{
	int err;

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

	mmc_claim_host(host);

	err = mmc_init_card(host, host->ocr, host->card);
	if (err != MMC_ERR_NONE) {
		mmc_remove(host);
		mmc_detach_bus(host);
	}

	mmc_release_host(host);
}

#else

#define mmc_suspend NULL
#define mmc_resume NULL

#endif

static const struct mmc_bus_ops mmc_ops = {
	.remove = mmc_remove,
	.detect = mmc_detect,
	.sysfs_add = mmc_sysfs_add,
	.sysfs_remove = mmc_sysfs_remove,
	.suspend = mmc_suspend,
	.resume = mmc_resume,
};

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

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

	mmc_attach_bus(host, &mmc_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;
	}

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

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

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

	mmc_release_host(host);

	err = mmc_add_card(host->card);
	if (err)
		goto reclaim_host;

	return 0;

reclaim_host:
	mmc_claim_host(host);
	mmc_remove_card(host->card);
	host->card = NULL;
err:
	mmc_detach_bus(host);
	mmc_release_host(host);

	return 0;
}