summaryrefslogtreecommitdiffstats
path: root/drivers/mmc/core/sdio.c
blob: aa0719a4dfd16c28f2f1ee03adf5f170016e4cdc (plain)
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
585
586
587
588
589
590
591
592
593
594
595
596
597
598
599
600
601
602
603
604
605
606
607
608
609
610
611
612
613
614
615
616
617
618
619
620
621
622
623
624
625
626
627
628
629
630
631
632
633
634
635
636
637
638
639
640
641
642
643
644
645
646
647
648
649
650
651
652
653
654
655
656
657
658
659
660
661
662
663
664
665
666
667
668
669
670
671
672
673
674
675
676
677
678
679
680
681
682
683
684
685
686
687
688
689
690
691
692
693
694
695
696
697
698
699
700
701
702
703
704
705
706
707
708
709
710
711
712
713
714
715
716
717
718
719
720
721
722
723
724
725
726
727
728
729
730
731
732
733
734
735
736
737
738
739
740
741
742
743
744
745
746
747
748
749
750
751
752
753
754
755
756
757
758
759
760
761
762
763
764
765
766
767
768
769
770
771
772
773
774
775
776
777
778
779
780
781
782
783
784
785
786
787
788
789
790
791
792
793
794
795
796
797
798
799
800
801
802
803
804
805
806
807
808
809
810
811
812
813
814
815
816
817
818
819
820
821
822
823
824
825
826
827
828
829
830
831
832
833
834
835
836
837
838
839
840
841
842
843
844
845
846
847
848
849
850
851
852
853
854
855
856
857
858
859
860
861
862
863
864
865
866
867
868
869
870
871
872
873
874
875
876
877
878
879
880
881
882
883
884
885
886
887
888
889
890
891
892
893
894
895
896
897
898
899
900
901
902
903
904
905
906
907
908
909
910
911
912
913
914
915
916
917
918
919
920
921
922
923
924
925
926
927
928
929
930
931
932
933
934
935
936
937
938
939
940
941
942
943
944
945
946
947
948
949
950
951
952
953
954
955
956
957
958
959
960
961
962
963
964
965
966
967
968
969
970
971
972
973
974
975
976
977
978
979
980
981
982
983
984
985
986
987
988
989
990
991
992
993
994
995
996
997
998
999
1000
1001
1002
1003
1004
1005
1006
1007
1008
1009
1010
1011
1012
1013
1014
1015
1016
1017
1018
1019
1020
1021
1022
1023
1024
1025
1026
1027
1028
1029
1030
1031
1032
1033
1034
1035
1036
1037
1038
1039
1040
1041
1042
1043
1044
1045
1046
1047
1048
1049
1050
1051
1052
1053
1054
1055
1056
1057
1058
1059
1060
1061
1062
1063
1064
1065
1066
1067
1068
1069
1070
1071
1072
1073
1074
1075
1076
1077
1078
1079
1080
1081
1082
1083
1084
1085
1086
1087
1088
1089
1090
1091
1092
1093
1094
1095
1096
1097
1098
1099
1100
1101
1102
1103
1104
1105
1106
1107
1108
1109
1110
1111
1112
1113
1114
1115
1116
1117
1118
1119
1120
1121
1122
1123
1124
1125
1126
1127
1128
1129
1130
1131
1132
1133
1134
1135
1136
1137
1138
1139
1140
1141
1142
1143
1144
1145
1146
1147
1148
1149
1150
1151
1152
1153
1154
1155
1156
1157
1158
1159
1160
1161
1162
1163
1164
1165
1166
1167
1168
1169
1170
1171
1172
1173
1174
1175
1176
1177
1178
1179
1180
1181
1182
1183
1184
1185
1186
1187
1188
1189
1190
1191
1192
1193
1194
1195
1196
1197
1198
1199
1200
1201
1202
/*
 *  linux/drivers/mmc/sdio.c
 *
 *  Copyright 2006-2007 Pierre Ossman
 *
 * This program is free software; you can redistribute it and/or modify
 * it under the terms of the GNU General Public License as published by
 * the Free Software Foundation; either version 2 of the License, or (at
 * your option) any later version.
 */

#include <linux/err.h>
#include <linux/pm_runtime.h>

#include <linux/mmc/host.h>
#include <linux/mmc/card.h>
#include <linux/mmc/mmc.h>
#include <linux/mmc/sdio.h>
#include <linux/mmc/sdio_func.h>
#include <linux/mmc/sdio_ids.h>

#include "core.h"
#include "bus.h"
#include "sd.h"
#include "sdio_bus.h"
#include "mmc_ops.h"
#include "sd_ops.h"
#include "sdio_ops.h"
#include "sdio_cis.h"

static int sdio_read_fbr(struct sdio_func *func)
{
	int ret;
	unsigned char data;

	if (mmc_card_nonstd_func_interface(func->card)) {
		func->class = SDIO_CLASS_NONE;
		return 0;
	}

	ret = mmc_io_rw_direct(func->card, 0, 0,
		SDIO_FBR_BASE(func->num) + SDIO_FBR_STD_IF, 0, &data);
	if (ret)
		goto out;

	data &= 0x0f;

	if (data == 0x0f) {
		ret = mmc_io_rw_direct(func->card, 0, 0,
			SDIO_FBR_BASE(func->num) + SDIO_FBR_STD_IF_EXT, 0, &data);
		if (ret)
			goto out;
	}

	func->class = data;

out:
	return ret;
}

static int sdio_init_func(struct mmc_card *card, unsigned int fn)
{
	int ret;
	struct sdio_func *func;

	BUG_ON(fn > SDIO_MAX_FUNCS);

	func = sdio_alloc_func(card);
	if (IS_ERR(func))
		return PTR_ERR(func);

	func->num = fn;

	if (!(card->quirks & MMC_QUIRK_NONSTD_SDIO)) {
		ret = sdio_read_fbr(func);
		if (ret)
			goto fail;

		ret = sdio_read_func_cis(func);
		if (ret)
			goto fail;
	} else {
		func->vendor = func->card->cis.vendor;
		func->device = func->card->cis.device;
		func->max_blksize = func->card->cis.blksize;
	}

	card->sdio_func[fn - 1] = func;

	return 0;

fail:
	/*
	 * It is okay to remove the function here even though we hold
	 * the host lock as we haven't registered the device yet.
	 */
	sdio_remove_func(func);
	return ret;
}

static int sdio_read_cccr(struct mmc_card *card, u32 ocr)
{
	int ret;
	int cccr_vsn;
	int uhs = ocr & R4_18V_PRESENT;
	unsigned char data;
	unsigned char speed;

	memset(&card->cccr, 0, sizeof(struct sdio_cccr));

	ret = mmc_io_rw_direct(card, 0, 0, SDIO_CCCR_CCCR, 0, &data);
	if (ret)
		goto out;

	cccr_vsn = data & 0x0f;

	if (cccr_vsn > SDIO_CCCR_REV_3_00) {
		pr_err("%s: unrecognised CCCR structure version %d\n",
			mmc_hostname(card->host), cccr_vsn);
		return -EINVAL;
	}

	card->cccr.sdio_vsn = (data & 0xf0) >> 4;

	ret = mmc_io_rw_direct(card, 0, 0, SDIO_CCCR_CAPS, 0, &data);
	if (ret)
		goto out;

	if (data & SDIO_CCCR_CAP_SMB)
		card->cccr.multi_block = 1;
	if (data & SDIO_CCCR_CAP_LSC)
		card->cccr.low_speed = 1;
	if (data & SDIO_CCCR_CAP_4BLS)
		card->cccr.wide_bus = 1;

	if (cccr_vsn >= SDIO_CCCR_REV_1_10) {
		ret = mmc_io_rw_direct(card, 0, 0, SDIO_CCCR_POWER, 0, &data);
		if (ret)
			goto out;

		if (data & SDIO_POWER_SMPC)
			card->cccr.high_power = 1;
	}

	if (cccr_vsn >= SDIO_CCCR_REV_1_20) {
		ret = mmc_io_rw_direct(card, 0, 0, SDIO_CCCR_SPEED, 0, &speed);
		if (ret)
			goto out;

		card->scr.sda_spec3 = 0;
		card->sw_caps.sd3_bus_mode = 0;
		card->sw_caps.sd3_drv_type = 0;
		if (cccr_vsn >= SDIO_CCCR_REV_3_00 && uhs) {
			card->scr.sda_spec3 = 1;
			ret = mmc_io_rw_direct(card, 0, 0,
				SDIO_CCCR_UHS, 0, &data);
			if (ret)
				goto out;

			if (mmc_host_uhs(card->host)) {
				if (data & SDIO_UHS_DDR50)
					card->sw_caps.sd3_bus_mode
						|= SD_MODE_UHS_DDR50;

				if (data & SDIO_UHS_SDR50)
					card->sw_caps.sd3_bus_mode
						|= SD_MODE_UHS_SDR50;

				if (data & SDIO_UHS_SDR104)
					card->sw_caps.sd3_bus_mode
						|= SD_MODE_UHS_SDR104;
			}

			ret = mmc_io_rw_direct(card, 0, 0,
				SDIO_CCCR_DRIVE_STRENGTH, 0, &data);
			if (ret)
				goto out;

			if (data & SDIO_DRIVE_SDTA)
				card->sw_caps.sd3_drv_type |= SD_DRIVER_TYPE_A;
			if (data & SDIO_DRIVE_SDTC)
				card->sw_caps.sd3_drv_type |= SD_DRIVER_TYPE_C;
			if (data & SDIO_DRIVE_SDTD)
				card->sw_caps.sd3_drv_type |= SD_DRIVER_TYPE_D;
		}

		/* if no uhs mode ensure we check for high speed */
		if (!card->sw_caps.sd3_bus_mode) {
			if (speed & SDIO_SPEED_SHS) {
				card->cccr.high_speed = 1;
				card->sw_caps.hs_max_dtr = 50000000;
			} else {
				card->cccr.high_speed = 0;
				card->sw_caps.hs_max_dtr = 25000000;
			}
		}
	}

out:
	return ret;
}

static int sdio_enable_wide(struct mmc_card *card)
{
	int ret;
	u8 ctrl;

	if (!(card->host->caps & MMC_CAP_4_BIT_DATA))
		return 0;

	if (card->cccr.low_speed && !card->cccr.wide_bus)
		return 0;

	ret = mmc_io_rw_direct(card, 0, 0, SDIO_CCCR_IF, 0, &ctrl);
	if (ret)
		return ret;

	if ((ctrl & SDIO_BUS_WIDTH_MASK) == SDIO_BUS_WIDTH_RESERVED)
		pr_warning("%s: SDIO_CCCR_IF is invalid: 0x%02x\n",
			   mmc_hostname(card->host), ctrl);

	/* set as 4-bit bus width */
	ctrl &= ~SDIO_BUS_WIDTH_MASK;
	ctrl |= SDIO_BUS_WIDTH_4BIT;

	ret = mmc_io_rw_direct(card, 1, 0, SDIO_CCCR_IF, ctrl, NULL);
	if (ret)
		return ret;

	return 1;
}

/*
 * If desired, disconnect the pull-up resistor on CD/DAT[3] (pin 1)
 * of the card. This may be required on certain setups of boards,
 * controllers and embedded sdio device which do not need the card's
 * pull-up. As a result, card detection is disabled and power is saved.
 */
static int sdio_disable_cd(struct mmc_card *card)
{
	int ret;
	u8 ctrl;

	if (!mmc_card_disable_cd(card))
		return 0;

	ret = mmc_io_rw_direct(card, 0, 0, SDIO_CCCR_IF, 0, &ctrl);
	if (ret)
		return ret;

	ctrl |= SDIO_BUS_CD_DISABLE;

	return mmc_io_rw_direct(card, 1, 0, SDIO_CCCR_IF, ctrl, NULL);
}

/*
 * Devices that remain active during a system suspend are
 * put back into 1-bit mode.
 */
static int sdio_disable_wide(struct mmc_card *card)
{
	int ret;
	u8 ctrl;

	if (!(card->host->caps & MMC_CAP_4_BIT_DATA))
		return 0;

	if (card->cccr.low_speed && !card->cccr.wide_bus)
		return 0;

	ret = mmc_io_rw_direct(card, 0, 0, SDIO_CCCR_IF, 0, &ctrl);
	if (ret)
		return ret;

	if (!(ctrl & SDIO_BUS_WIDTH_4BIT))
		return 0;

	ctrl &= ~SDIO_BUS_WIDTH_4BIT;
	ctrl |= SDIO_BUS_ASYNC_INT;

	ret = mmc_io_rw_direct(card, 1, 0, SDIO_CCCR_IF, ctrl, NULL);
	if (ret)
		return ret;

	mmc_set_bus_width(card->host, MMC_BUS_WIDTH_1);

	return 0;
}


static int sdio_enable_4bit_bus(struct mmc_card *card)
{
	int err;

	if (card->type == MMC_TYPE_SDIO)
		return sdio_enable_wide(card);

	if ((card->host->caps & MMC_CAP_4_BIT_DATA) &&
		(card->scr.bus_widths & SD_SCR_BUS_WIDTH_4)) {
		err = mmc_app_set_bus_width(card, MMC_BUS_WIDTH_4);
		if (err)
			return err;
	} else
		return 0;

	err = sdio_enable_wide(card);
	if (err <= 0)
		mmc_app_set_bus_width(card, MMC_BUS_WIDTH_1);

	return err;
}


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

	if (!(card->host->caps & MMC_CAP_SD_HIGHSPEED))
		return 0;

	if (!card->cccr.high_speed)
		return 0;

	ret = mmc_io_rw_direct(card, 0, 0, SDIO_CCCR_SPEED, 0, &speed);
	if (ret)
		return ret;

	if (enable)
		speed |= SDIO_SPEED_EHS;
	else
		speed &= ~SDIO_SPEED_EHS;

	ret = mmc_io_rw_direct(card, 1, 0, SDIO_CCCR_SPEED, speed, NULL);
	if (ret)
		return ret;

	return 1;
}

/*
 * Enable SDIO/combo card's high-speed mode. Return 0/1 if [not]supported.
 */
static int sdio_enable_hs(struct mmc_card *card)
{
	int ret;

	ret = mmc_sdio_switch_hs(card, true);
	if (ret <= 0 || card->type == MMC_TYPE_SDIO)
		return ret;

	ret = mmc_sd_switch_hs(card);
	if (ret <= 0)
		mmc_sdio_switch_hs(card, false);

	return ret;
}

static unsigned mmc_sdio_get_max_clock(struct mmc_card *card)
{
	unsigned max_dtr;

	if (mmc_card_highspeed(card)) {
		/*
		 * The SDIO specification doesn't mention how
		 * the CIS transfer speed register relates to
		 * high-speed, but it seems that 50 MHz is
		 * mandatory.
		 */
		max_dtr = 50000000;
	} else {
		max_dtr = card->cis.max_dtr;
	}

	if (card->type == MMC_TYPE_SD_COMBO)
		max_dtr = min(max_dtr, mmc_sd_get_max_clock(card));

	return max_dtr;
}

static unsigned char host_drive_to_sdio_drive(int host_strength)
{
	switch (host_strength) {
	case MMC_SET_DRIVER_TYPE_A:
		return SDIO_DTSx_SET_TYPE_A;
	case MMC_SET_DRIVER_TYPE_B:
		return SDIO_DTSx_SET_TYPE_B;
	case MMC_SET_DRIVER_TYPE_C:
		return SDIO_DTSx_SET_TYPE_C;
	case MMC_SET_DRIVER_TYPE_D:
		return SDIO_DTSx_SET_TYPE_D;
	default:
		return SDIO_DTSx_SET_TYPE_B;
	}
}

static void sdio_select_driver_type(struct mmc_card *card)
{
	int host_drv_type = SD_DRIVER_TYPE_B;
	int card_drv_type = SD_DRIVER_TYPE_B;
	int drive_strength;
	unsigned char card_strength;
	int err;

	/*
	 * If the host doesn't support any of the Driver Types A,C or D,
	 * or there is no board specific handler then default Driver
	 * Type B is used.
	 */
	if (!(card->host->caps &
		(MMC_CAP_DRIVER_TYPE_A |
		 MMC_CAP_DRIVER_TYPE_C |
		 MMC_CAP_DRIVER_TYPE_D)))
		return;

	if (!card->host->ops->select_drive_strength)
		return;

	if (card->host->caps & MMC_CAP_DRIVER_TYPE_A)
		host_drv_type |= SD_DRIVER_TYPE_A;

	if (card->host->caps & MMC_CAP_DRIVER_TYPE_C)
		host_drv_type |= SD_DRIVER_TYPE_C;

	if (card->host->caps & MMC_CAP_DRIVER_TYPE_D)
		host_drv_type |= SD_DRIVER_TYPE_D;

	if (card->sw_caps.sd3_drv_type & SD_DRIVER_TYPE_A)
		card_drv_type |= SD_DRIVER_TYPE_A;

	if (card->sw_caps.sd3_drv_type & SD_DRIVER_TYPE_C)
		card_drv_type |= SD_DRIVER_TYPE_C;

	if (card->sw_caps.sd3_drv_type & SD_DRIVER_TYPE_D)
		card_drv_type |= SD_DRIVER_TYPE_D;

	/*
	 * The drive strength that the hardware can support
	 * depends on the board design.  Pass the appropriate
	 * information and let the hardware specific code
	 * return what is possible given the options
	 */
	drive_strength = card->host->ops->select_drive_strength(
		card->sw_caps.uhs_max_dtr,
		host_drv_type, card_drv_type);

	/* if error just use default for drive strength B */
	err = mmc_io_rw_direct(card, 0, 0, SDIO_CCCR_DRIVE_STRENGTH, 0,
		&card_strength);
	if (err)
		return;

	card_strength &= ~(SDIO_DRIVE_DTSx_MASK<<SDIO_DRIVE_DTSx_SHIFT);
	card_strength |= host_drive_to_sdio_drive(drive_strength);

	err = mmc_io_rw_direct(card, 1, 0, SDIO_CCCR_DRIVE_STRENGTH,
		card_strength, NULL);

	/* if error default to drive strength B */
	if (!err)
		mmc_set_driver_type(card->host, drive_strength);
}


static int sdio_set_bus_speed_mode(struct mmc_card *card)
{
	unsigned int bus_speed, timing;
	int err;
	unsigned char speed;

	/*
	 * If the host doesn't support any of the UHS-I modes, fallback on
	 * default speed.
	 */
	if (!mmc_host_uhs(card->host))
		return 0;

	bus_speed = SDIO_SPEED_SDR12;
	timing = MMC_TIMING_UHS_SDR12;
	if ((card->host->caps & MMC_CAP_UHS_SDR104) &&
	    (card->sw_caps.sd3_bus_mode & SD_MODE_UHS_SDR104)) {
			bus_speed = SDIO_SPEED_SDR104;
			timing = MMC_TIMING_UHS_SDR104;
			card->sw_caps.uhs_max_dtr = UHS_SDR104_MAX_DTR;
			card->sd_bus_speed = UHS_SDR104_BUS_SPEED;
	} else if ((card->host->caps & MMC_CAP_UHS_DDR50) &&
		   (card->sw_caps.sd3_bus_mode & SD_MODE_UHS_DDR50)) {
			bus_speed = SDIO_SPEED_DDR50;
			timing = MMC_TIMING_UHS_DDR50;
			card->sw_caps.uhs_max_dtr = UHS_DDR50_MAX_DTR;
			card->sd_bus_speed = UHS_DDR50_BUS_SPEED;
	} else if ((card->host->caps & (MMC_CAP_UHS_SDR104 |
		    MMC_CAP_UHS_SDR50)) && (card->sw_caps.sd3_bus_mode &
		    SD_MODE_UHS_SDR50)) {
			bus_speed = SDIO_SPEED_SDR50;
			timing = MMC_TIMING_UHS_SDR50;
			card->sw_caps.uhs_max_dtr = UHS_SDR50_MAX_DTR;
			card->sd_bus_speed = UHS_SDR50_BUS_SPEED;
	} else if ((card->host->caps & (MMC_CAP_UHS_SDR104 |
		    MMC_CAP_UHS_SDR50 | MMC_CAP_UHS_SDR25)) &&
		   (card->sw_caps.sd3_bus_mode & SD_MODE_UHS_SDR25)) {
			bus_speed = SDIO_SPEED_SDR25;
			timing = MMC_TIMING_UHS_SDR25;
			card->sw_caps.uhs_max_dtr = UHS_SDR25_MAX_DTR;
			card->sd_bus_speed = UHS_SDR25_BUS_SPEED;
	} else if ((card->host->caps & (MMC_CAP_UHS_SDR104 |
		    MMC_CAP_UHS_SDR50 | MMC_CAP_UHS_SDR25 |
		    MMC_CAP_UHS_SDR12)) && (card->sw_caps.sd3_bus_mode &
		    SD_MODE_UHS_SDR12)) {
			bus_speed = SDIO_SPEED_SDR12;
			timing = MMC_TIMING_UHS_SDR12;
			card->sw_caps.uhs_max_dtr = UHS_SDR12_MAX_DTR;
			card->sd_bus_speed = UHS_SDR12_BUS_SPEED;
	}

	err = mmc_io_rw_direct(card, 0, 0, SDIO_CCCR_SPEED, 0, &speed);
	if (err)
		return err;

	speed &= ~SDIO_SPEED_BSS_MASK;
	speed |= bus_speed;
	err = mmc_io_rw_direct(card, 1, 0, SDIO_CCCR_SPEED, speed, NULL);
	if (err)
		return err;

	if (bus_speed) {
		mmc_set_timing(card->host, timing);
		mmc_set_clock(card->host, card->sw_caps.uhs_max_dtr);
	}

	return 0;
}

/*
 * UHS-I specific initialization procedure
 */
static int mmc_sdio_init_uhs_card(struct mmc_card *card)
{
	int err;

	if (!card->scr.sda_spec3)
		return 0;

	/*
	 * Switch to wider bus (if supported).
	 */
	if (card->host->caps & MMC_CAP_4_BIT_DATA) {
		err = sdio_enable_4bit_bus(card);
		if (err > 0) {
			mmc_set_bus_width(card->host, MMC_BUS_WIDTH_4);
			err = 0;
		}
	}

	/* Set the driver strength for the card */
	sdio_select_driver_type(card);

	/* Set bus speed mode of the card */
	err = sdio_set_bus_speed_mode(card);
	if (err)
		goto out;

	/* Initialize and start re-tuning timer */
	if (!mmc_host_is_spi(card->host) && card->host->ops->execute_tuning)
		err = card->host->ops->execute_tuning(card->host,
						      MMC_SEND_TUNING_BLOCK);

out:

	return err;
}

/*
 * Handle the detection and initialisation of a card.
 *
 * In the case of a resume, "oldcard" will contain the card
 * we're trying to reinitialise.
 */
static int mmc_sdio_init_card(struct mmc_host *host, u32 ocr,
			      struct mmc_card *oldcard, int powered_resume)
{
	struct mmc_card *card;
	int err;
	int retries = 10;

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

try_again:
	if (!retries) {
		pr_warning("%s: Skipping voltage switch\n",
				mmc_hostname(host));
		ocr &= ~R4_18V_PRESENT;
		host->ocr &= ~R4_18V_PRESENT;
	}

	/*
	 * Inform the card of the voltage
	 */
	if (!powered_resume) {
		err = mmc_send_io_op_cond(host, host->ocr, &ocr);
		if (err)
			goto err;
	}

	/*
	 * For SPI, enable CRC as appropriate.
	 */
	if (mmc_host_is_spi(host)) {
		err = mmc_spi_set_crc(host, use_spi_crc);
		if (err)
			goto err;
	}

	/*
	 * Allocate card structure.
	 */
	card = mmc_alloc_card(host, NULL);
	if (IS_ERR(card)) {
		err = PTR_ERR(card);
		goto err;
	}

	if ((ocr & R4_MEMORY_PRESENT) &&
	    mmc_sd_get_cid(host, host->ocr & ocr, card->raw_cid, NULL) == 0) {
		card->type = MMC_TYPE_SD_COMBO;

		if (oldcard && (oldcard->type != MMC_TYPE_SD_COMBO ||
		    memcmp(card->raw_cid, oldcard->raw_cid, sizeof(card->raw_cid)) != 0)) {
			mmc_remove_card(card);
			return -ENOENT;
		}
	} else {
		card->type = MMC_TYPE_SDIO;

		if (oldcard && oldcard->type != MMC_TYPE_SDIO) {
			mmc_remove_card(card);
			return -ENOENT;
		}
	}

	/*
	 * Call the optional HC's init_card function to handle quirks.
	 */
	if (host->ops->init_card)
		host->ops->init_card(host, card);

	/*
	 * If the host and card support UHS-I mode request the card
	 * to switch to 1.8V signaling level.  No 1.8v signalling if
	 * UHS mode is not enabled to maintain compatibility and some
	 * systems that claim 1.8v signalling in fact do not support
	 * it.
	 */
	if (!powered_resume && (ocr & R4_18V_PRESENT) && mmc_host_uhs(host)) {
		err = mmc_set_signal_voltage(host, MMC_SIGNAL_VOLTAGE_180);
		if (err == -EAGAIN) {
			sdio_reset(host);
			mmc_go_idle(host);
			mmc_send_if_cond(host, host->ocr_avail);
			mmc_remove_card(card);
			retries--;
			goto try_again;
		} else if (err) {
			ocr &= ~R4_18V_PRESENT;
			host->ocr &= ~R4_18V_PRESENT;
		}
		err = 0;
	} else {
		ocr &= ~R4_18V_PRESENT;
		host->ocr &= ~R4_18V_PRESENT;
	}

	/*
	 * For native busses:  set card RCA and quit open drain mode.
	 */
	if (!powered_resume && !mmc_host_is_spi(host)) {
		err = mmc_send_relative_addr(host, &card->rca);
		if (err)
			goto remove;

		/*
		 * Update oldcard with the new RCA received from the SDIO
		 * device -- we're doing this so that it's updated in the
		 * "card" struct when oldcard overwrites that later.
		 */
		if (oldcard)
			oldcard->rca = card->rca;
	}

	/*
	 * Read CSD, before selecting the card
	 */
	if (!oldcard && card->type == MMC_TYPE_SD_COMBO) {
		err = mmc_sd_get_csd(host, card);
		if (err)
			return err;

		mmc_decode_cid(card);
	}

	/*
	 * Select card, as all following commands rely on that.
	 */
	if (!powered_resume && !mmc_host_is_spi(host)) {
		err = mmc_select_card(card);
		if (err)
			goto remove;
	}

	if (card->quirks & MMC_QUIRK_NONSTD_SDIO) {
		/*
		 * This is non-standard SDIO device, meaning it doesn't
		 * have any CIA (Common I/O area) registers present.
		 * It's host's responsibility to fill cccr and cis
		 * structures in init_card().
		 */
		mmc_set_clock(host, card->cis.max_dtr);

		if (card->cccr.high_speed) {
			mmc_card_set_highspeed(card);
			mmc_set_timing(card->host, MMC_TIMING_SD_HS);
		}

		goto finish;
	}

	/*
	 * Read the common registers.
	 */
	err = sdio_read_cccr(card, ocr);
	if (err)
		goto remove;

	/*
	 * Read the common CIS tuples.
	 */
	err = sdio_read_common_cis(card);
	if (err)
		goto remove;

	if (oldcard) {
		int same = (card->cis.vendor == oldcard->cis.vendor &&
			    card->cis.device == oldcard->cis.device);
		mmc_remove_card(card);
		if (!same)
			return -ENOENT;

		card = oldcard;
	}
	mmc_fixup_device(card, NULL);

	if (card->type == MMC_TYPE_SD_COMBO) {
		err = mmc_sd_setup_card(host, card, oldcard != NULL);
		/* handle as SDIO-only card if memory init failed */
		if (err) {
			mmc_go_idle(host);
			if (mmc_host_is_spi(host))
				/* should not fail, as it worked previously */
				mmc_spi_set_crc(host, use_spi_crc);
			card->type = MMC_TYPE_SDIO;
		} else
			card->dev.type = &sd_type;
	}

	/*
	 * If needed, disconnect card detection pull-up resistor.
	 */
	err = sdio_disable_cd(card);
	if (err)
		goto remove;

	/* Initialization sequence for UHS-I cards */
	/* Only if card supports 1.8v and UHS signaling */
	if ((ocr & R4_18V_PRESENT) && card->sw_caps.sd3_bus_mode) {
		err = mmc_sdio_init_uhs_card(card);
		if (err)
			goto remove;

		/* Card is an ultra-high-speed card */
		mmc_card_set_uhs(card);
	} else {
		/*
		 * Switch to high-speed (if supported).
		 */
		err = sdio_enable_hs(card);
		if (err > 0)
			mmc_sd_go_highspeed(card);
		else if (err)
			goto remove;

		/*
		 * Change to the card's maximum speed.
		 */
		mmc_set_clock(host, mmc_sdio_get_max_clock(card));

		/*
		 * Switch to wider bus (if supported).
		 */
		err = sdio_enable_4bit_bus(card);
		if (err > 0)
			mmc_set_bus_width(card->host, MMC_BUS_WIDTH_4);
		else if (err)
			goto remove;
	}
finish:
	if (!oldcard)
		host->card = card;
	return 0;

remove:
	if (!oldcard)
		mmc_remove_card(card);

err:
	return err;
}

/*
 * Host is being removed. Free up the current card.
 */
static void mmc_sdio_remove(struct mmc_host *host)
{
	int i;

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

	for (i = 0;i < host->card->sdio_funcs;i++) {
		if (host->card->sdio_func[i]) {
			sdio_remove_func(host->card->sdio_func[i]);
			host->card->sdio_func[i] = NULL;
		}
	}

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

/*
 * Card detection - card is alive.
 */
static int mmc_sdio_alive(struct mmc_host *host)
{
	return mmc_select_card(host->card);
}

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

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

	/* Make sure card is powered before detecting it */
	if (host->caps & MMC_CAP_POWER_OFF_CARD) {
		err = pm_runtime_get_sync(&host->card->dev);
		if (err < 0)
			goto out;
	}

	mmc_claim_host(host);

	/*
	 * Just check if our card has been removed.
	 */
	err = _mmc_detect_card_removed(host);

	mmc_release_host(host);

	/*
	 * Tell PM core it's OK to power off the card now.
	 *
	 * The _sync variant is used in order to ensure that the card
	 * is left powered off in case an error occurred, and the card
	 * is going to be removed.
	 *
	 * Since there is no specific reason to believe a new user
	 * is about to show up at this point, the _sync variant is
	 * desirable anyway.
	 */
	if (host->caps & MMC_CAP_POWER_OFF_CARD)
		pm_runtime_put_sync(&host->card->dev);

out:
	if (err) {
		mmc_sdio_remove(host);

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

/*
 * SDIO suspend.  We need to suspend all functions separately.
 * Therefore all registered functions must have drivers with suspend
 * and resume methods.  Failing that we simply remove the whole card.
 */
static int mmc_sdio_suspend(struct mmc_host *host)
{
	int i, err = 0;

	for (i = 0; i < host->card->sdio_funcs; i++) {
		struct sdio_func *func = host->card->sdio_func[i];
		if (func && sdio_func_present(func) && func->dev.driver) {
			const struct dev_pm_ops *pmops = func->dev.driver->pm;
			if (!pmops || !pmops->suspend || !pmops->resume) {
				/* force removal of entire card in that case */
				err = -ENOSYS;
			} else
				err = pmops->suspend(&func->dev);
			if (err)
				break;
		}
	}
	while (err && --i >= 0) {
		struct sdio_func *func = host->card->sdio_func[i];
		if (func && sdio_func_present(func) && func->dev.driver) {
			const struct dev_pm_ops *pmops = func->dev.driver->pm;
			pmops->resume(&func->dev);
		}
	}

	if (!err && mmc_card_keep_power(host) && mmc_card_wake_sdio_irq(host)) {
		mmc_claim_host(host);
		sdio_disable_wide(host->card);
		mmc_release_host(host);
	}

	return err;
}

static int mmc_sdio_resume(struct mmc_host *host)
{
	int i, err = 0;

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

	/* Basic card reinitialization. */
	mmc_claim_host(host);

	/* No need to reinitialize powered-resumed nonremovable cards */
	if (mmc_card_is_removable(host) || !mmc_card_keep_power(host)) {
		sdio_reset(host);
		mmc_go_idle(host);
		err = mmc_sdio_init_card(host, host->ocr, host->card,
					mmc_card_keep_power(host));
	} else if (mmc_card_keep_power(host) && mmc_card_wake_sdio_irq(host)) {
		/* We may have switched to 1-bit mode during suspend */
		err = sdio_enable_4bit_bus(host->card);
		if (err > 0) {
			mmc_set_bus_width(host, MMC_BUS_WIDTH_4);
			err = 0;
		}
	}

	if (!err && host->sdio_irqs)
		wake_up_process(host->sdio_irq_thread);
	mmc_release_host(host);

	/*
	 * If the card looked to be the same as before suspending, then
	 * we proceed to resume all card functions.  If one of them returns
	 * an error then we simply return that error to the core and the
	 * card will be redetected as new.  It is the responsibility of
	 * the function driver to perform further tests with the extra
	 * knowledge it has of the card to confirm the card is indeed the
	 * same as before suspending (same MAC address for network cards,
	 * etc.) and return an error otherwise.
	 */
	for (i = 0; !err && i < host->card->sdio_funcs; i++) {
		struct sdio_func *func = host->card->sdio_func[i];
		if (func && sdio_func_present(func) && func->dev.driver) {
			const struct dev_pm_ops *pmops = func->dev.driver->pm;
			err = pmops->resume(&func->dev);
		}
	}

	return err;
}

static int mmc_sdio_power_restore(struct mmc_host *host)
{
	int ret;
	u32 ocr;

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

	mmc_claim_host(host);

	/*
	 * Reset the card by performing the same steps that are taken by
	 * mmc_rescan_try_freq() and mmc_attach_sdio() during a "normal" probe.
	 *
	 * sdio_reset() is technically not needed. Having just powered up the
	 * hardware, it should already be in reset state. However, some
	 * platforms (such as SD8686 on OLPC) do not instantly cut power,
	 * meaning that a reset is required when restoring power soon after
	 * powering off. It is harmless in other cases.
	 *
	 * The CMD5 reset (mmc_send_io_op_cond()), according to the SDIO spec,
	 * is not necessary for non-removable cards. However, it is required
	 * for OLPC SD8686 (which expects a [CMD5,5,3,7] init sequence), and
	 * harmless in other situations.
	 *
	 * With these steps taken, mmc_select_voltage() is also required to
	 * restore the correct voltage setting of the card.
	 */

	sdio_reset(host);
	mmc_go_idle(host);
	mmc_send_if_cond(host, host->ocr_avail);

	ret = mmc_send_io_op_cond(host, 0, &ocr);
	if (ret)
		goto out;

	if (host->ocr_avail_sdio)
		host->ocr_avail = host->ocr_avail_sdio;

	host->ocr = mmc_select_voltage(host, ocr & ~0x7F);
	if (!host->ocr) {
		ret = -EINVAL;
		goto out;
	}

	if (mmc_host_uhs(host))
		/* to query card if 1.8V signalling is supported */
		host->ocr |= R4_18V_PRESENT;

	ret = mmc_sdio_init_card(host, host->ocr, host->card,
				mmc_card_keep_power(host));
	if (!ret && host->sdio_irqs)
		mmc_signal_sdio_irq(host);

out:
	mmc_release_host(host);

	return ret;
}

static const struct mmc_bus_ops mmc_sdio_ops = {
	.remove = mmc_sdio_remove,
	.detect = mmc_sdio_detect,
	.suspend = mmc_sdio_suspend,
	.resume = mmc_sdio_resume,
	.power_restore = mmc_sdio_power_restore,
	.alive = mmc_sdio_alive,
};


/*
 * Starting point for SDIO card init.
 */
int mmc_attach_sdio(struct mmc_host *host)
{
	int err, i, funcs;
	u32 ocr;
	struct mmc_card *card;

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

	err = mmc_send_io_op_cond(host, 0, &ocr);
	if (err)
		return err;

	mmc_attach_bus(host, &mmc_sdio_ops);
	if (host->ocr_avail_sdio)
		host->ocr_avail = host->ocr_avail_sdio;

	/*
	 * Sanity check the voltages that the card claims to
	 * support.
	 */
	if (ocr & 0x7F) {
		pr_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(s) of the card(s)?
	 */
	if (!host->ocr) {
		err = -EINVAL;
		goto err;
	}

	/*
	 * Detect and init the card.
	 */
	if (mmc_host_uhs(host))
		/* to query card if 1.8V signalling is supported */
		host->ocr |= R4_18V_PRESENT;

	err = mmc_sdio_init_card(host, host->ocr, NULL, 0);
	if (err) {
		if (err == -EAGAIN) {
			/*
			 * Retry initialization with S18R set to 0.
			 */
			host->ocr &= ~R4_18V_PRESENT;
			err = mmc_sdio_init_card(host, host->ocr, NULL, 0);
		}
		if (err)
			goto err;
	}
	card = host->card;

	/*
	 * Enable runtime PM only if supported by host+card+board
	 */
	if (host->caps & MMC_CAP_POWER_OFF_CARD) {
		/*
		 * Let runtime PM core know our card is active
		 */
		err = pm_runtime_set_active(&card->dev);
		if (err)
			goto remove;

		/*
		 * Enable runtime PM for this card
		 */
		pm_runtime_enable(&card->dev);
	}

	/*
	 * The number of functions on the card is encoded inside
	 * the ocr.
	 */
	funcs = (ocr & 0x70000000) >> 28;
	card->sdio_funcs = 0;

	/*
	 * Initialize (but don't add) all present functions.
	 */
	for (i = 0; i < funcs; i++, card->sdio_funcs++) {
		err = sdio_init_func(host->card, i + 1);
		if (err)
			goto remove;

		/*
		 * Enable Runtime PM for this func (if supported)
		 */
		if (host->caps & MMC_CAP_POWER_OFF_CARD)
			pm_runtime_enable(&card->sdio_func[i]->dev);
	}

	/*
	 * First add the card to the driver model...
	 */
	mmc_release_host(host);
	err = mmc_add_card(host->card);
	if (err)
		goto remove_added;

	/*
	 * ...then the SDIO functions.
	 */
	for (i = 0;i < funcs;i++) {
		err = sdio_add_func(host->card->sdio_func[i]);
		if (err)
			goto remove_added;
	}

	mmc_claim_host(host);
	return 0;


remove_added:
	/* Remove without lock if the device has been added. */
	mmc_sdio_remove(host);
	mmc_claim_host(host);
remove:
	/* And with lock if it hasn't been added. */
	mmc_release_host(host);
	if (host->card)
		mmc_sdio_remove(host);
	mmc_claim_host(host);
err:
	mmc_detach_bus(host);

	pr_err("%s: error %d whilst initialising SDIO card\n",
		mmc_hostname(host), err);

	return err;
}