summaryrefslogtreecommitdiff
path: root/drivers/mmc/host/tifm_sd.c
blob: d1760ebcac0359e6e25273ac849f4c89f60f6b2b (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
/*
 *  tifm_sd.c - TI FlashMedia driver
 *
 *  Copyright (C) 2006 Alex Dubov <oakad@yahoo.com>
 *
 * 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.
 *
 * Special thanks to Brad Campbell for extensive testing of this driver.
 *
 */


#include <linux/tifm.h>
#include <linux/mmc/host.h>
#include <linux/highmem.h>
#include <linux/scatterlist.h>
#include <linux/module.h>
#include <asm/io.h>

#define DRIVER_NAME "tifm_sd"
#define DRIVER_VERSION "0.8"

static bool no_dma = 0;
static bool fixed_timeout = 0;
module_param(no_dma, bool, 0644);
module_param(fixed_timeout, bool, 0644);

/* Constants here are mostly from OMAP5912 datasheet */
#define TIFM_MMCSD_RESET      0x0002
#define TIFM_MMCSD_CLKMASK    0x03ff
#define TIFM_MMCSD_POWER      0x0800
#define TIFM_MMCSD_4BBUS      0x8000
#define TIFM_MMCSD_RXDE       0x8000   /* rx dma enable */
#define TIFM_MMCSD_TXDE       0x0080   /* tx dma enable */
#define TIFM_MMCSD_BUFINT     0x0c00   /* set bits: AE, AF */
#define TIFM_MMCSD_DPE        0x0020   /* data timeout counted in kilocycles */
#define TIFM_MMCSD_INAB       0x0080   /* abort / initialize command */
#define TIFM_MMCSD_READ       0x8000

#define TIFM_MMCSD_ERRMASK    0x01e0   /* set bits: CCRC, CTO, DCRC, DTO */
#define TIFM_MMCSD_EOC        0x0001   /* end of command phase  */
#define TIFM_MMCSD_CD         0x0002   /* card detect           */
#define TIFM_MMCSD_CB         0x0004   /* card enter busy state */
#define TIFM_MMCSD_BRS        0x0008   /* block received/sent   */
#define TIFM_MMCSD_EOFB       0x0010   /* card exit busy state  */
#define TIFM_MMCSD_DTO        0x0020   /* data time-out         */
#define TIFM_MMCSD_DCRC       0x0040   /* data crc error        */
#define TIFM_MMCSD_CTO        0x0080   /* command time-out      */
#define TIFM_MMCSD_CCRC       0x0100   /* command crc error     */
#define TIFM_MMCSD_AF         0x0400   /* fifo almost full      */
#define TIFM_MMCSD_AE         0x0800   /* fifo almost empty     */
#define TIFM_MMCSD_OCRB       0x1000   /* OCR busy              */
#define TIFM_MMCSD_CIRQ       0x2000   /* card irq (cmd40/sdio) */
#define TIFM_MMCSD_CERR       0x4000   /* card status error     */

#define TIFM_MMCSD_ODTO       0x0040   /* open drain / extended timeout */
#define TIFM_MMCSD_CARD_RO    0x0200   /* card is read-only     */

#define TIFM_MMCSD_FIFO_SIZE  0x0020

#define TIFM_MMCSD_RSP_R0     0x0000
#define TIFM_MMCSD_RSP_R1     0x0100
#define TIFM_MMCSD_RSP_R2     0x0200
#define TIFM_MMCSD_RSP_R3     0x0300
#define TIFM_MMCSD_RSP_R4     0x0400
#define TIFM_MMCSD_RSP_R5     0x0500
#define TIFM_MMCSD_RSP_R6     0x0600

#define TIFM_MMCSD_RSP_BUSY   0x0800

#define TIFM_MMCSD_CMD_BC     0x0000
#define TIFM_MMCSD_CMD_BCR    0x1000
#define TIFM_MMCSD_CMD_AC     0x2000
#define TIFM_MMCSD_CMD_ADTC   0x3000

#define TIFM_MMCSD_MAX_BLOCK_SIZE  0x0800UL

enum {
	CMD_READY    = 0x0001,
	FIFO_READY   = 0x0002,
	BRS_READY    = 0x0004,
	SCMD_ACTIVE  = 0x0008,
	SCMD_READY   = 0x0010,
	CARD_BUSY    = 0x0020,
	DATA_CARRY   = 0x0040
};

struct tifm_sd {
	struct tifm_dev       *dev;

	unsigned short        eject:1,
			      open_drain:1,
			      no_dma:1;
	unsigned short        cmd_flags;

	unsigned int          clk_freq;
	unsigned int          clk_div;
	unsigned long         timeout_jiffies;

	struct tasklet_struct finish_tasklet;
	struct timer_list     timer;
	struct mmc_request    *req;

	int                   sg_len;
	int                   sg_pos;
	unsigned int          block_pos;
	struct scatterlist    bounce_buf;
	unsigned char         bounce_buf_data[TIFM_MMCSD_MAX_BLOCK_SIZE];
};

/* for some reason, host won't respond correctly to readw/writew */
static void tifm_sd_read_fifo(struct tifm_sd *host, struct page *pg,
			      unsigned int off, unsigned int cnt)
{
	struct tifm_dev *sock = host->dev;
	unsigned char *buf;
	unsigned int pos = 0, val;

	buf = kmap_atomic(pg) + off;
	if (host->cmd_flags & DATA_CARRY) {
		buf[pos++] = host->bounce_buf_data[0];
		host->cmd_flags &= ~DATA_CARRY;
	}

	while (pos < cnt) {
		val = readl(sock->addr + SOCK_MMCSD_DATA);
		buf[pos++] = val & 0xff;
		if (pos == cnt) {
			host->bounce_buf_data[0] = (val >> 8) & 0xff;
			host->cmd_flags |= DATA_CARRY;
			break;
		}
		buf[pos++] = (val >> 8) & 0xff;
	}
	kunmap_atomic(buf - off);
}

static void tifm_sd_write_fifo(struct tifm_sd *host, struct page *pg,
			       unsigned int off, unsigned int cnt)
{
	struct tifm_dev *sock = host->dev;
	unsigned char *buf;
	unsigned int pos = 0, val;

	buf = kmap_atomic(pg) + off;
	if (host->cmd_flags & DATA_CARRY) {
		val = host->bounce_buf_data[0] | ((buf[pos++] << 8) & 0xff00);
		writel(val, sock->addr + SOCK_MMCSD_DATA);
		host->cmd_flags &= ~DATA_CARRY;
	}

	while (pos < cnt) {
		val = buf[pos++];
		if (pos == cnt) {
			host->bounce_buf_data[0] = val & 0xff;
			host->cmd_flags |= DATA_CARRY;
			break;
		}
		val |= (buf[pos++] << 8) & 0xff00;
		writel(val, sock->addr + SOCK_MMCSD_DATA);
	}
	kunmap_atomic(buf - off);
}

static void tifm_sd_transfer_data(struct tifm_sd *host)
{
	struct mmc_data *r_data = host->req->cmd->data;
	struct scatterlist *sg = r_data->sg;
	unsigned int off, cnt, t_size = TIFM_MMCSD_FIFO_SIZE * 2;
	unsigned int p_off, p_cnt;
	struct page *pg;

	if (host->sg_pos == host->sg_len)
		return;
	while (t_size) {
		cnt = sg[host->sg_pos].length - host->block_pos;
		if (!cnt) {
			host->block_pos = 0;
			host->sg_pos++;
			if (host->sg_pos == host->sg_len) {
				if ((r_data->flags & MMC_DATA_WRITE)
				    && (host->cmd_flags & DATA_CARRY))
					writel(host->bounce_buf_data[0],
					       host->dev->addr
					       + SOCK_MMCSD_DATA);

				return;
			}
			cnt = sg[host->sg_pos].length;
		}
		off = sg[host->sg_pos].offset + host->block_pos;

		pg = nth_page(sg_page(&sg[host->sg_pos]), off >> PAGE_SHIFT);
		p_off = offset_in_page(off);
		p_cnt = PAGE_SIZE - p_off;
		p_cnt = min(p_cnt, cnt);
		p_cnt = min(p_cnt, t_size);

		if (r_data->flags & MMC_DATA_READ)
			tifm_sd_read_fifo(host, pg, p_off, p_cnt);
		else if (r_data->flags & MMC_DATA_WRITE)
			tifm_sd_write_fifo(host, pg, p_off, p_cnt);

		t_size -= p_cnt;
		host->block_pos += p_cnt;
	}
}

static void tifm_sd_copy_page(struct page *dst, unsigned int dst_off,
			      struct page *src, unsigned int src_off,
			      unsigned int count)
{
	unsigned char *src_buf = kmap_atomic(src) + src_off;
	unsigned char *dst_buf = kmap_atomic(dst) + dst_off;

	memcpy(dst_buf, src_buf, count);

	kunmap_atomic(dst_buf - dst_off);
	kunmap_atomic(src_buf - src_off);
}

static void tifm_sd_bounce_block(struct tifm_sd *host, struct mmc_data *r_data)
{
	struct scatterlist *sg = r_data->sg;
	unsigned int t_size = r_data->blksz;
	unsigned int off, cnt;
	unsigned int p_off, p_cnt;
	struct page *pg;

	dev_dbg(&host->dev->dev, "bouncing block\n");
	while (t_size) {
		cnt = sg[host->sg_pos].length - host->block_pos;
		if (!cnt) {
			host->block_pos = 0;
			host->sg_pos++;
			if (host->sg_pos == host->sg_len)
				return;
			cnt = sg[host->sg_pos].length;
		}
		off = sg[host->sg_pos].offset + host->block_pos;

		pg = nth_page(sg_page(&sg[host->sg_pos]), off >> PAGE_SHIFT);
		p_off = offset_in_page(off);
		p_cnt = PAGE_SIZE - p_off;
		p_cnt = min(p_cnt, cnt);
		p_cnt = min(p_cnt, t_size);

		if (r_data->flags & MMC_DATA_WRITE)
			tifm_sd_copy_page(sg_page(&host->bounce_buf),
					  r_data->blksz - t_size,
					  pg, p_off, p_cnt);
		else if (r_data->flags & MMC_DATA_READ)
			tifm_sd_copy_page(pg, p_off, sg_page(&host->bounce_buf),
					  r_data->blksz - t_size, p_cnt);

		t_size -= p_cnt;
		host->block_pos += p_cnt;
	}
}

static int tifm_sd_set_dma_data(struct tifm_sd *host, struct mmc_data *r_data)
{
	struct tifm_dev *sock = host->dev;
	unsigned int t_size = TIFM_DMA_TSIZE * r_data->blksz;
	unsigned int dma_len, dma_blk_cnt, dma_off;
	struct scatterlist *sg = NULL;
	unsigned long flags;

	if (host->sg_pos == host->sg_len)
		return 1;

	if (host->cmd_flags & DATA_CARRY) {
		host->cmd_flags &= ~DATA_CARRY;
		local_irq_save(flags);
		tifm_sd_bounce_block(host, r_data);
		local_irq_restore(flags);
		if (host->sg_pos == host->sg_len)
			return 1;
	}

	dma_len = sg_dma_len(&r_data->sg[host->sg_pos]) - host->block_pos;
	if (!dma_len) {
		host->block_pos = 0;
		host->sg_pos++;
		if (host->sg_pos == host->sg_len)
			return 1;
		dma_len = sg_dma_len(&r_data->sg[host->sg_pos]);
	}

	if (dma_len < t_size) {
		dma_blk_cnt = dma_len / r_data->blksz;
		dma_off = host->block_pos;
		host->block_pos += dma_blk_cnt * r_data->blksz;
	} else {
		dma_blk_cnt = TIFM_DMA_TSIZE;
		dma_off = host->block_pos;
		host->block_pos += t_size;
	}

	if (dma_blk_cnt)
		sg = &r_data->sg[host->sg_pos];
	else if (dma_len) {
		if (r_data->flags & MMC_DATA_WRITE) {
			local_irq_save(flags);
			tifm_sd_bounce_block(host, r_data);
			local_irq_restore(flags);
		} else
			host->cmd_flags |= DATA_CARRY;

		sg = &host->bounce_buf;
		dma_off = 0;
		dma_blk_cnt = 1;
	} else
		return 1;

	dev_dbg(&sock->dev, "setting dma for %d blocks\n", dma_blk_cnt);
	writel(sg_dma_address(sg) + dma_off, sock->addr + SOCK_DMA_ADDRESS);
	if (r_data->flags & MMC_DATA_WRITE)
		writel((dma_blk_cnt << 8) | TIFM_DMA_TX | TIFM_DMA_EN,
		       sock->addr + SOCK_DMA_CONTROL);
	else
		writel((dma_blk_cnt << 8) | TIFM_DMA_EN,
		       sock->addr + SOCK_DMA_CONTROL);

	return 0;
}

static unsigned int tifm_sd_op_flags(struct mmc_command *cmd)
{
	unsigned int rc = 0;

	switch (mmc_resp_type(cmd)) {
	case MMC_RSP_NONE:
		rc |= TIFM_MMCSD_RSP_R0;
		break;
	case MMC_RSP_R1B:
		rc |= TIFM_MMCSD_RSP_BUSY; // deliberate fall-through
	case MMC_RSP_R1:
		rc |= TIFM_MMCSD_RSP_R1;
		break;
	case MMC_RSP_R2:
		rc |= TIFM_MMCSD_RSP_R2;
		break;
	case MMC_RSP_R3:
		rc |= TIFM_MMCSD_RSP_R3;
		break;
	default:
		BUG();
	}

	switch (mmc_cmd_type(cmd)) {
	case MMC_CMD_BC:
		rc |= TIFM_MMCSD_CMD_BC;
		break;
	case MMC_CMD_BCR:
		rc |= TIFM_MMCSD_CMD_BCR;
		break;
	case MMC_CMD_AC:
		rc |= TIFM_MMCSD_CMD_AC;
		break;
	case MMC_CMD_ADTC:
		rc |= TIFM_MMCSD_CMD_ADTC;
		break;
	default:
		BUG();
	}
	return rc;
}

static void tifm_sd_exec(struct tifm_sd *host, struct mmc_command *cmd)
{
	struct tifm_dev *sock = host->dev;
	unsigned int cmd_mask = tifm_sd_op_flags(cmd);

	if (host->open_drain)
		cmd_mask |= TIFM_MMCSD_ODTO;

	if (cmd->data && (cmd->data->flags & MMC_DATA_READ))
		cmd_mask |= TIFM_MMCSD_READ;

	dev_dbg(&sock->dev, "executing opcode 0x%x, arg: 0x%x, mask: 0x%x\n",
		cmd->opcode, cmd->arg, cmd_mask);

	writel((cmd->arg >> 16) & 0xffff, sock->addr + SOCK_MMCSD_ARG_HIGH);
	writel(cmd->arg & 0xffff, sock->addr + SOCK_MMCSD_ARG_LOW);
	writel(cmd->opcode | cmd_mask, sock->addr + SOCK_MMCSD_COMMAND);
}

static void tifm_sd_fetch_resp(struct mmc_command *cmd, struct tifm_dev *sock)
{
	cmd->resp[0] = (readl(sock->addr + SOCK_MMCSD_RESPONSE + 0x1c) << 16)
		       | readl(sock->addr + SOCK_MMCSD_RESPONSE + 0x18);
	cmd->resp[1] = (readl(sock->addr + SOCK_MMCSD_RESPONSE + 0x14) << 16)
		       | readl(sock->addr + SOCK_MMCSD_RESPONSE + 0x10);
	cmd->resp[2] = (readl(sock->addr + SOCK_MMCSD_RESPONSE + 0x0c) << 16)
		       | readl(sock->addr + SOCK_MMCSD_RESPONSE + 0x08);
	cmd->resp[3] = (readl(sock->addr + SOCK_MMCSD_RESPONSE + 0x04) << 16)
		       | readl(sock->addr + SOCK_MMCSD_RESPONSE + 0x00);
}

static void tifm_sd_check_status(struct tifm_sd *host)
{
	struct tifm_dev *sock = host->dev;
	struct mmc_command *cmd = host->req->cmd;

	if (cmd->error)
		goto finish_request;

	if (!(host->cmd_flags & CMD_READY))
		return;

	if (cmd->data) {
		if (cmd->data->error) {
			if ((host->cmd_flags & SCMD_ACTIVE)
			    && !(host->cmd_flags & SCMD_READY))
				return;

			goto finish_request;
		}

		if (!(host->cmd_flags & BRS_READY))
			return;

		if (!(host->no_dma || (host->cmd_flags & FIFO_READY)))
			return;

		if (cmd->data->flags & MMC_DATA_WRITE) {
			if (host->req->stop) {
				if (!(host->cmd_flags & SCMD_ACTIVE)) {
					host->cmd_flags |= SCMD_ACTIVE;
					writel(TIFM_MMCSD_EOFB
					       | readl(sock->addr
						       + SOCK_MMCSD_INT_ENABLE),
					       sock->addr
					       + SOCK_MMCSD_INT_ENABLE);
					tifm_sd_exec(host, host->req->stop);
					return;
				} else {
					if (!(host->cmd_flags & SCMD_READY)
					    || (host->cmd_flags & CARD_BUSY))
						return;
					writel((~TIFM_MMCSD_EOFB)
					       & readl(sock->addr
						       + SOCK_MMCSD_INT_ENABLE),
					       sock->addr
					       + SOCK_MMCSD_INT_ENABLE);
				}
			} else {
				if (host->cmd_flags & CARD_BUSY)
					return;
				writel((~TIFM_MMCSD_EOFB)
				       & readl(sock->addr
					       + SOCK_MMCSD_INT_ENABLE),
				       sock->addr + SOCK_MMCSD_INT_ENABLE);
			}
		} else {
			if (host->req->stop) {
				if (!(host->cmd_flags & SCMD_ACTIVE)) {
					host->cmd_flags |= SCMD_ACTIVE;
					tifm_sd_exec(host, host->req->stop);
					return;
				} else {
					if (!(host->cmd_flags & SCMD_READY))
						return;
				}
			}
		}
	}
finish_request:
	tasklet_schedule(&host->finish_tasklet);
}

/* Called from interrupt handler */
static void tifm_sd_data_event(struct tifm_dev *sock)
{
	struct tifm_sd *host;
	unsigned int fifo_status = 0;
	struct mmc_data *r_data = NULL;

	spin_lock(&sock->lock);
	host = mmc_priv((struct mmc_host*)tifm_get_drvdata(sock));
	fifo_status = readl(sock->addr + SOCK_DMA_FIFO_STATUS);
	dev_dbg(&sock->dev, "data event: fifo_status %x, flags %x\n",
		fifo_status, host->cmd_flags);

	if (host->req) {
		r_data = host->req->cmd->data;

		if (r_data && (fifo_status & TIFM_FIFO_READY)) {
			if (tifm_sd_set_dma_data(host, r_data)) {
				host->cmd_flags |= FIFO_READY;
				tifm_sd_check_status(host);
			}
		}
	}

	writel(fifo_status, sock->addr + SOCK_DMA_FIFO_STATUS);
	spin_unlock(&sock->lock);
}

/* Called from interrupt handler */
static void tifm_sd_card_event(struct tifm_dev *sock)
{
	struct tifm_sd *host;
	unsigned int host_status = 0;
	int cmd_error = 0;
	struct mmc_command *cmd = NULL;
	unsigned long flags;

	spin_lock(&sock->lock);
	host = mmc_priv((struct mmc_host*)tifm_get_drvdata(sock));
	host_status = readl(sock->addr + SOCK_MMCSD_STATUS);
	dev_dbg(&sock->dev, "host event: host_status %x, flags %x\n",
		host_status, host->cmd_flags);

	if (host->req) {
		cmd = host->req->cmd;

		if (host_status & TIFM_MMCSD_ERRMASK) {
			writel(host_status & TIFM_MMCSD_ERRMASK,
			       sock->addr + SOCK_MMCSD_STATUS);
			if (host_status & TIFM_MMCSD_CTO)
				cmd_error = -ETIMEDOUT;
			else if (host_status & TIFM_MMCSD_CCRC)
				cmd_error = -EILSEQ;

			if (cmd->data) {
				if (host_status & TIFM_MMCSD_DTO)
					cmd->data->error = -ETIMEDOUT;
				else if (host_status & TIFM_MMCSD_DCRC)
					cmd->data->error = -EILSEQ;
			}

			writel(TIFM_FIFO_INT_SETALL,
			       sock->addr + SOCK_DMA_FIFO_INT_ENABLE_CLEAR);
			writel(TIFM_DMA_RESET, sock->addr + SOCK_DMA_CONTROL);

			if (host->req->stop) {
				if (host->cmd_flags & SCMD_ACTIVE) {
					host->req->stop->error = cmd_error;
					host->cmd_flags |= SCMD_READY;
				} else {
					cmd->error = cmd_error;
					host->cmd_flags |= SCMD_ACTIVE;
					tifm_sd_exec(host, host->req->stop);
					goto done;
				}
			} else
				cmd->error = cmd_error;
		} else {
			if (host_status & (TIFM_MMCSD_EOC | TIFM_MMCSD_CERR)) {
				if (!(host->cmd_flags & CMD_READY)) {
					host->cmd_flags |= CMD_READY;
					tifm_sd_fetch_resp(cmd, sock);
				} else if (host->cmd_flags & SCMD_ACTIVE) {
					host->cmd_flags |= SCMD_READY;
					tifm_sd_fetch_resp(host->req->stop,
							   sock);
				}
			}
			if (host_status & TIFM_MMCSD_BRS)
				host->cmd_flags |= BRS_READY;
		}

		if (host->no_dma && cmd->data) {
			if (host_status & TIFM_MMCSD_AE)
				writel(host_status & TIFM_MMCSD_AE,
				       sock->addr + SOCK_MMCSD_STATUS);

			if (host_status & (TIFM_MMCSD_AE | TIFM_MMCSD_AF
					   | TIFM_MMCSD_BRS)) {
				local_irq_save(flags);
				tifm_sd_transfer_data(host);
				local_irq_restore(flags);
				host_status &= ~TIFM_MMCSD_AE;
			}
		}

		if (host_status & TIFM_MMCSD_EOFB)
			host->cmd_flags &= ~CARD_BUSY;
		else if (host_status & TIFM_MMCSD_CB)
			host->cmd_flags |= CARD_BUSY;

		tifm_sd_check_status(host);
	}
done:
	writel(host_status, sock->addr + SOCK_MMCSD_STATUS);
	spin_unlock(&sock->lock);
}

static void tifm_sd_set_data_timeout(struct tifm_sd *host,
				     struct mmc_data *data)
{
	struct tifm_dev *sock = host->dev;
	unsigned int data_timeout = data->timeout_clks;

	if (fixed_timeout)
		return;

	data_timeout += data->timeout_ns /
			((1000000000UL / host->clk_freq) * host->clk_div);

	if (data_timeout < 0xffff) {
		writel(data_timeout, sock->addr + SOCK_MMCSD_DATA_TO);
		writel((~TIFM_MMCSD_DPE)
		       & readl(sock->addr + SOCK_MMCSD_SDIO_MODE_CONFIG),
		       sock->addr + SOCK_MMCSD_SDIO_MODE_CONFIG);
	} else {
		data_timeout = (data_timeout >> 10) + 1;
		if (data_timeout > 0xffff)
			data_timeout = 0;	/* set to unlimited */
		writel(data_timeout, sock->addr + SOCK_MMCSD_DATA_TO);
		writel(TIFM_MMCSD_DPE
		       | readl(sock->addr + SOCK_MMCSD_SDIO_MODE_CONFIG),
		       sock->addr + SOCK_MMCSD_SDIO_MODE_CONFIG);
	}
}

static void tifm_sd_request(struct mmc_host *mmc, struct mmc_request *mrq)
{
	struct tifm_sd *host = mmc_priv(mmc);
	struct tifm_dev *sock = host->dev;
	unsigned long flags;
	struct mmc_data *r_data = mrq->cmd->data;

	spin_lock_irqsave(&sock->lock, flags);
	if (host->eject) {
		mrq->cmd->error = -ENOMEDIUM;
		goto err_out;
	}

	if (host->req) {
		pr_err("%s : unfinished request detected\n",
		       dev_name(&sock->dev));
		mrq->cmd->error = -ETIMEDOUT;
		goto err_out;
	}

	host->cmd_flags = 0;
	host->block_pos = 0;
	host->sg_pos = 0;

	if (mrq->data && !is_power_of_2(mrq->data->blksz))
		host->no_dma = 1;
	else
		host->no_dma = no_dma ? 1 : 0;

	if (r_data) {
		tifm_sd_set_data_timeout(host, r_data);

		if ((r_data->flags & MMC_DATA_WRITE) && !mrq->stop)
			 writel(TIFM_MMCSD_EOFB
				| readl(sock->addr + SOCK_MMCSD_INT_ENABLE),
				sock->addr + SOCK_MMCSD_INT_ENABLE);

		if (host->no_dma) {
			writel(TIFM_MMCSD_BUFINT
			       | readl(sock->addr + SOCK_MMCSD_INT_ENABLE),
			       sock->addr + SOCK_MMCSD_INT_ENABLE);
			writel(((TIFM_MMCSD_FIFO_SIZE - 1) << 8)
			       | (TIFM_MMCSD_FIFO_SIZE - 1),
			       sock->addr + SOCK_MMCSD_BUFFER_CONFIG);

			host->sg_len = r_data->sg_len;
		} else {
			sg_init_one(&host->bounce_buf, host->bounce_buf_data,
				    r_data->blksz);

			if(1 != tifm_map_sg(sock, &host->bounce_buf, 1,
					    r_data->flags & MMC_DATA_WRITE
					    ? PCI_DMA_TODEVICE
					    : PCI_DMA_FROMDEVICE)) {
				pr_err("%s : scatterlist map failed\n",
				       dev_name(&sock->dev));
				mrq->cmd->error = -ENOMEM;
				goto err_out;
			}
			host->sg_len = tifm_map_sg(sock, r_data->sg,
						   r_data->sg_len,
						   r_data->flags
						   & MMC_DATA_WRITE
						   ? PCI_DMA_TODEVICE
						   : PCI_DMA_FROMDEVICE);
			if (host->sg_len < 1) {
				pr_err("%s : scatterlist map failed\n",
				       dev_name(&sock->dev));
				tifm_unmap_sg(sock, &host->bounce_buf, 1,
					      r_data->flags & MMC_DATA_WRITE
					      ? PCI_DMA_TODEVICE
					      : PCI_DMA_FROMDEVICE);
				mrq->cmd->error = -ENOMEM;
				goto err_out;
			}

			writel(TIFM_FIFO_INT_SETALL,
			       sock->addr + SOCK_DMA_FIFO_INT_ENABLE_CLEAR);
			writel(ilog2(r_data->blksz) - 2,
			       sock->addr + SOCK_FIFO_PAGE_SIZE);
			writel(TIFM_FIFO_ENABLE,
			       sock->addr + SOCK_FIFO_CONTROL);
			writel(TIFM_FIFO_INTMASK,
			       sock->addr + SOCK_DMA_FIFO_INT_ENABLE_SET);

			if (r_data->flags & MMC_DATA_WRITE)
				writel(TIFM_MMCSD_TXDE,
				       sock->addr + SOCK_MMCSD_BUFFER_CONFIG);
			else
				writel(TIFM_MMCSD_RXDE,
				       sock->addr + SOCK_MMCSD_BUFFER_CONFIG);

			tifm_sd_set_dma_data(host, r_data);
		}

		writel(r_data->blocks - 1,
		       sock->addr + SOCK_MMCSD_NUM_BLOCKS);
		writel(r_data->blksz - 1,
		       sock->addr + SOCK_MMCSD_BLOCK_LEN);
	}

	host->req = mrq;
	mod_timer(&host->timer, jiffies + host->timeout_jiffies);
	writel(TIFM_CTRL_LED | readl(sock->addr + SOCK_CONTROL),
	       sock->addr + SOCK_CONTROL);
	tifm_sd_exec(host, mrq->cmd);
	spin_unlock_irqrestore(&sock->lock, flags);
	return;

err_out:
	spin_unlock_irqrestore(&sock->lock, flags);
	mmc_request_done(mmc, mrq);
}

static void tifm_sd_end_cmd(unsigned long data)
{
	struct tifm_sd *host = (struct tifm_sd*)data;
	struct tifm_dev *sock = host->dev;
	struct mmc_host *mmc = tifm_get_drvdata(sock);
	struct mmc_request *mrq;
	struct mmc_data *r_data = NULL;
	unsigned long flags;

	spin_lock_irqsave(&sock->lock, flags);

	del_timer(&host->timer);
	mrq = host->req;
	host->req = NULL;

	if (!mrq) {
		pr_err(" %s : no request to complete?\n",
		       dev_name(&sock->dev));
		spin_unlock_irqrestore(&sock->lock, flags);
		return;
	}

	r_data = mrq->cmd->data;
	if (r_data) {
		if (host->no_dma) {
			writel((~TIFM_MMCSD_BUFINT)
			       & readl(sock->addr + SOCK_MMCSD_INT_ENABLE),
			       sock->addr + SOCK_MMCSD_INT_ENABLE);
		} else {
			tifm_unmap_sg(sock, &host->bounce_buf, 1,
				      (r_data->flags & MMC_DATA_WRITE)
				      ? PCI_DMA_TODEVICE : PCI_DMA_FROMDEVICE);
			tifm_unmap_sg(sock, r_data->sg, r_data->sg_len,
				      (r_data->flags & MMC_DATA_WRITE)
				      ? PCI_DMA_TODEVICE : PCI_DMA_FROMDEVICE);
		}

		r_data->bytes_xfered = r_data->blocks
			- readl(sock->addr + SOCK_MMCSD_NUM_BLOCKS) - 1;
		r_data->bytes_xfered *= r_data->blksz;
		r_data->bytes_xfered += r_data->blksz
			- readl(sock->addr + SOCK_MMCSD_BLOCK_LEN) + 1;
	}

	writel((~TIFM_CTRL_LED) & readl(sock->addr + SOCK_CONTROL),
	       sock->addr + SOCK_CONTROL);

	spin_unlock_irqrestore(&sock->lock, flags);
	mmc_request_done(mmc, mrq);
}

static void tifm_sd_abort(unsigned long data)
{
	struct tifm_sd *host = (struct tifm_sd*)data;

	pr_err("%s : card failed to respond for a long period of time "
	       "(%x, %x)\n",
	       dev_name(&host->dev->dev), host->req->cmd->opcode, host->cmd_flags);

	tifm_eject(host->dev);
}

static void tifm_sd_ios(struct mmc_host *mmc, struct mmc_ios *ios)
{
	struct tifm_sd *host = mmc_priv(mmc);
	struct tifm_dev *sock = host->dev;
	unsigned int clk_div1, clk_div2;
	unsigned long flags;

	spin_lock_irqsave(&sock->lock, flags);

	dev_dbg(&sock->dev, "ios: clock = %u, vdd = %x, bus_mode = %x, "
		"chip_select = %x, power_mode = %x, bus_width = %x\n",
		ios->clock, ios->vdd, ios->bus_mode, ios->chip_select,
		ios->power_mode, ios->bus_width);

	if (ios->bus_width == MMC_BUS_WIDTH_4) {
		writel(TIFM_MMCSD_4BBUS | readl(sock->addr + SOCK_MMCSD_CONFIG),
		       sock->addr + SOCK_MMCSD_CONFIG);
	} else {
		writel((~TIFM_MMCSD_4BBUS)
		       & readl(sock->addr + SOCK_MMCSD_CONFIG),
		       sock->addr + SOCK_MMCSD_CONFIG);
	}

	if (ios->clock) {
		clk_div1 = 20000000 / ios->clock;
		if (!clk_div1)
			clk_div1 = 1;

		clk_div2 = 24000000 / ios->clock;
		if (!clk_div2)
			clk_div2 = 1;

		if ((20000000 / clk_div1) > ios->clock)
			clk_div1++;
		if ((24000000 / clk_div2) > ios->clock)
			clk_div2++;
		if ((20000000 / clk_div1) > (24000000 / clk_div2)) {
			host->clk_freq = 20000000;
			host->clk_div = clk_div1;
			writel((~TIFM_CTRL_FAST_CLK)
			       & readl(sock->addr + SOCK_CONTROL),
			       sock->addr + SOCK_CONTROL);
		} else {
			host->clk_freq = 24000000;
			host->clk_div = clk_div2;
			writel(TIFM_CTRL_FAST_CLK
			       | readl(sock->addr + SOCK_CONTROL),
			       sock->addr + SOCK_CONTROL);
		}
	} else {
		host->clk_div = 0;
	}
	host->clk_div &= TIFM_MMCSD_CLKMASK;
	writel(host->clk_div
	       | ((~TIFM_MMCSD_CLKMASK)
		  & readl(sock->addr + SOCK_MMCSD_CONFIG)),
	       sock->addr + SOCK_MMCSD_CONFIG);

	host->open_drain = (ios->bus_mode == MMC_BUSMODE_OPENDRAIN);

	/* chip_select : maybe later */
	//vdd
	//power is set before probe / after remove

	spin_unlock_irqrestore(&sock->lock, flags);
}

static int tifm_sd_ro(struct mmc_host *mmc)
{
	int rc = 0;
	struct tifm_sd *host = mmc_priv(mmc);
	struct tifm_dev *sock = host->dev;
	unsigned long flags;

	spin_lock_irqsave(&sock->lock, flags);
	if (TIFM_MMCSD_CARD_RO & readl(sock->addr + SOCK_PRESENT_STATE))
		rc = 1;
	spin_unlock_irqrestore(&sock->lock, flags);
	return rc;
}

static const struct mmc_host_ops tifm_sd_ops = {
	.request = tifm_sd_request,
	.set_ios = tifm_sd_ios,
	.get_ro  = tifm_sd_ro
};

static int tifm_sd_initialize_host(struct tifm_sd *host)
{
	int rc;
	unsigned int host_status = 0;
	struct tifm_dev *sock = host->dev;

	writel(0, sock->addr + SOCK_MMCSD_INT_ENABLE);
	mmiowb();
	host->clk_div = 61;
	host->clk_freq = 20000000;
	writel(TIFM_MMCSD_RESET, sock->addr + SOCK_MMCSD_SYSTEM_CONTROL);
	writel(host->clk_div | TIFM_MMCSD_POWER,
	       sock->addr + SOCK_MMCSD_CONFIG);

	/* wait up to 0.51 sec for reset */
	for (rc = 32; rc <= 256; rc <<= 1) {
		if (1 & readl(sock->addr + SOCK_MMCSD_SYSTEM_STATUS)) {
			rc = 0;
			break;
		}
		msleep(rc);
	}

	if (rc) {
		pr_err("%s : controller failed to reset\n",
		       dev_name(&sock->dev));
		return -ENODEV;
	}

	writel(0, sock->addr + SOCK_MMCSD_NUM_BLOCKS);
	writel(host->clk_div | TIFM_MMCSD_POWER,
	       sock->addr + SOCK_MMCSD_CONFIG);
	writel(TIFM_MMCSD_RXDE, sock->addr + SOCK_MMCSD_BUFFER_CONFIG);

	// command timeout fixed to 64 clocks for now
	writel(64, sock->addr + SOCK_MMCSD_COMMAND_TO);
	writel(TIFM_MMCSD_INAB, sock->addr + SOCK_MMCSD_COMMAND);

	for (rc = 16; rc <= 64; rc <<= 1) {
		host_status = readl(sock->addr + SOCK_MMCSD_STATUS);
		writel(host_status, sock->addr + SOCK_MMCSD_STATUS);
		if (!(host_status & TIFM_MMCSD_ERRMASK)
		    && (host_status & TIFM_MMCSD_EOC)) {
			rc = 0;
			break;
		}
		msleep(rc);
	}

	if (rc) {
		pr_err("%s : card not ready - probe failed on initialization\n",
		       dev_name(&sock->dev));
		return -ENODEV;
	}

	writel(TIFM_MMCSD_CERR | TIFM_MMCSD_BRS | TIFM_MMCSD_EOC
	       | TIFM_MMCSD_ERRMASK,
	       sock->addr + SOCK_MMCSD_INT_ENABLE);
	mmiowb();

	return 0;
}

static int tifm_sd_probe(struct tifm_dev *sock)
{
	struct mmc_host *mmc;
	struct tifm_sd *host;
	int rc = -EIO;

	if (!(TIFM_SOCK_STATE_OCCUPIED
	      & readl(sock->addr + SOCK_PRESENT_STATE))) {
		pr_warning("%s : card gone, unexpectedly\n",
		       dev_name(&sock->dev));
		return rc;
	}

	mmc = mmc_alloc_host(sizeof(struct tifm_sd), &sock->dev);
	if (!mmc)
		return -ENOMEM;

	host = mmc_priv(mmc);
	tifm_set_drvdata(sock, mmc);
	host->dev = sock;
	host->timeout_jiffies = msecs_to_jiffies(1000);

	tasklet_init(&host->finish_tasklet, tifm_sd_end_cmd,
		     (unsigned long)host);
	setup_timer(&host->timer, tifm_sd_abort, (unsigned long)host);

	mmc->ops = &tifm_sd_ops;
	mmc->ocr_avail = MMC_VDD_32_33 | MMC_VDD_33_34;
	mmc->caps = MMC_CAP_4_BIT_DATA;
	mmc->f_min = 20000000 / 60;
	mmc->f_max = 24000000;

	mmc->max_blk_count = 2048;
	mmc->max_segs = mmc->max_blk_count;
	mmc->max_blk_size = min(TIFM_MMCSD_MAX_BLOCK_SIZE, PAGE_SIZE);
	mmc->max_seg_size = mmc->max_blk_count * mmc->max_blk_size;
	mmc->max_req_size = mmc->max_seg_size;

	sock->card_event = tifm_sd_card_event;
	sock->data_event = tifm_sd_data_event;
	rc = tifm_sd_initialize_host(host);

	if (!rc)
		rc = mmc_add_host(mmc);
	if (!rc)
		return 0;

	mmc_free_host(mmc);
	return rc;
}

static void tifm_sd_remove(struct tifm_dev *sock)
{
	struct mmc_host *mmc = tifm_get_drvdata(sock);
	struct tifm_sd *host = mmc_priv(mmc);
	unsigned long flags;

	spin_lock_irqsave(&sock->lock, flags);
	host->eject = 1;
	writel(0, sock->addr + SOCK_MMCSD_INT_ENABLE);
	mmiowb();
	spin_unlock_irqrestore(&sock->lock, flags);

	tasklet_kill(&host->finish_tasklet);

	spin_lock_irqsave(&sock->lock, flags);
	if (host->req) {
		writel(TIFM_FIFO_INT_SETALL,
		       sock->addr + SOCK_DMA_FIFO_INT_ENABLE_CLEAR);
		writel(0, sock->addr + SOCK_DMA_FIFO_INT_ENABLE_SET);
		host->req->cmd->error = -ENOMEDIUM;
		if (host->req->stop)
			host->req->stop->error = -ENOMEDIUM;
		tasklet_schedule(&host->finish_tasklet);
	}
	spin_unlock_irqrestore(&sock->lock, flags);
	mmc_remove_host(mmc);
	dev_dbg(&sock->dev, "after remove\n");

	mmc_free_host(mmc);
}

#ifdef CONFIG_PM

static int tifm_sd_suspend(struct tifm_dev *sock, pm_message_t state)
{
	return 0;
}

static int tifm_sd_resume(struct tifm_dev *sock)
{
	struct mmc_host *mmc = tifm_get_drvdata(sock);
	struct tifm_sd *host = mmc_priv(mmc);
	int rc;

	rc = tifm_sd_initialize_host(host);
	dev_dbg(&sock->dev, "resume initialize %d\n", rc);

	if (rc)
		host->eject = 1;

	return rc;
}

#else

#define tifm_sd_suspend NULL
#define tifm_sd_resume NULL

#endif /* CONFIG_PM */

static struct tifm_device_id tifm_sd_id_tbl[] = {
	{ TIFM_TYPE_SD }, { }
};

static struct tifm_driver tifm_sd_driver = {
	.driver = {
		.name  = DRIVER_NAME,
		.owner = THIS_MODULE
	},
	.id_table = tifm_sd_id_tbl,
	.probe    = tifm_sd_probe,
	.remove   = tifm_sd_remove,
	.suspend  = tifm_sd_suspend,
	.resume   = tifm_sd_resume
};

static int __init tifm_sd_init(void)
{
	return tifm_register_driver(&tifm_sd_driver);
}

static void __exit tifm_sd_exit(void)
{
	tifm_unregister_driver(&tifm_sd_driver);
}

MODULE_AUTHOR("Alex Dubov");
MODULE_DESCRIPTION("TI FlashMedia SD driver");
MODULE_LICENSE("GPL");
MODULE_DEVICE_TABLE(tifm, tifm_sd_id_tbl);
MODULE_VERSION(DRIVER_VERSION);

module_init(tifm_sd_init);
module_exit(tifm_sd_exit);