aboutsummaryrefslogtreecommitdiffstats
path: root/drivers/crypto/omap-sham.c
blob: 1d75e6f95a5877fab7c987dfe5b50bf2d8394017 (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
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
1203
1204
1205
1206
1207
1208
1209
1210
1211
1212
1213
1214
1215
1216
1217
1218
1219
1220
1221
1222
1223
1224
1225
1226
1227
1228
1229
1230
1231
1232
1233
1234
1235
1236
1237
1238
1239
1240
1241
1242
1243
1244
1245
1246
1247
1248
1249
1250
1251
1252
1253
1254
1255
1256
1257
1258
1259
1260
1261
1262
1263
1264
1265
1266
1267
1268
1269
1270
1271
1272
1273
1274
1275
1276
1277
1278
1279
1280
1281
1282
1283
1284
1285
1286
1287
1288
1289
1290
1291
1292
1293
1294
1295
1296
1297
1298
1299
1300
1301
1302
1303
1304
/*
 * Cryptographic API.
 *
 * Support for OMAP SHA1/MD5 HW acceleration.
 *
 * Copyright (c) 2010 Nokia Corporation
 * Author: Dmitry Kasatkin <dmitry.kasatkin@nokia.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.
 *
 * Some ideas are from old omap-sha1-md5.c driver.
 */

#define pr_fmt(fmt) "%s: " fmt, __func__

#include <linux/err.h>
#include <linux/device.h>
#include <linux/module.h>
#include <linux/init.h>
#include <linux/errno.h>
#include <linux/interrupt.h>
#include <linux/kernel.h>
#include <linux/clk.h>
#include <linux/irq.h>
#include <linux/io.h>
#include <linux/platform_device.h>
#include <linux/scatterlist.h>
#include <linux/dma-mapping.h>
#include <linux/delay.h>
#include <linux/crypto.h>
#include <linux/cryptohash.h>
#include <crypto/scatterwalk.h>
#include <crypto/algapi.h>
#include <crypto/sha.h>
#include <crypto/hash.h>
#include <crypto/internal/hash.h>

#include <linux/omap-dma.h>
#include <mach/irqs.h>

#define SHA_REG_DIGEST(x)		(0x00 + ((x) * 0x04))
#define SHA_REG_DIN(x)			(0x1C + ((x) * 0x04))

#define SHA1_MD5_BLOCK_SIZE		SHA1_BLOCK_SIZE
#define MD5_DIGEST_SIZE			16

#define SHA_REG_DIGCNT			0x14

#define SHA_REG_CTRL			0x18
#define SHA_REG_CTRL_LENGTH		(0xFFFFFFFF << 5)
#define SHA_REG_CTRL_CLOSE_HASH		(1 << 4)
#define SHA_REG_CTRL_ALGO_CONST		(1 << 3)
#define SHA_REG_CTRL_ALGO		(1 << 2)
#define SHA_REG_CTRL_INPUT_READY	(1 << 1)
#define SHA_REG_CTRL_OUTPUT_READY	(1 << 0)

#define SHA_REG_REV			0x5C
#define SHA_REG_REV_MAJOR		0xF0
#define SHA_REG_REV_MINOR		0x0F

#define SHA_REG_MASK			0x60
#define SHA_REG_MASK_DMA_EN		(1 << 3)
#define SHA_REG_MASK_IT_EN		(1 << 2)
#define SHA_REG_MASK_SOFTRESET		(1 << 1)
#define SHA_REG_AUTOIDLE		(1 << 0)

#define SHA_REG_SYSSTATUS		0x64
#define SHA_REG_SYSSTATUS_RESETDONE	(1 << 0)

#define DEFAULT_TIMEOUT_INTERVAL	HZ

/* mostly device flags */
#define FLAGS_BUSY		0
#define FLAGS_FINAL		1
#define FLAGS_DMA_ACTIVE	2
#define FLAGS_OUTPUT_READY	3
#define FLAGS_INIT		4
#define FLAGS_CPU		5
#define FLAGS_DMA_READY		6
/* context flags */
#define FLAGS_FINUP		16
#define FLAGS_SG		17
#define FLAGS_SHA1		18
#define FLAGS_HMAC		19
#define FLAGS_ERROR		20

#define OP_UPDATE	1
#define OP_FINAL	2

#define OMAP_ALIGN_MASK		(sizeof(u32)-1)
#define OMAP_ALIGNED		__attribute__((aligned(sizeof(u32))))

#define BUFLEN		PAGE_SIZE

struct omap_sham_dev;

struct omap_sham_reqctx {
	struct omap_sham_dev	*dd;
	unsigned long		flags;
	unsigned long		op;

	u8			digest[SHA1_DIGEST_SIZE] OMAP_ALIGNED;
	size_t			digcnt;
	size_t			bufcnt;
	size_t			buflen;
	dma_addr_t		dma_addr;

	/* walk state */
	struct scatterlist	*sg;
	unsigned int		offset;	/* offset in current sg */
	unsigned int		total;	/* total request */

	u8			buffer[0] OMAP_ALIGNED;
};

struct omap_sham_hmac_ctx {
	struct crypto_shash	*shash;
	u8			ipad[SHA1_MD5_BLOCK_SIZE];
	u8			opad[SHA1_MD5_BLOCK_SIZE];
};

struct omap_sham_ctx {
	struct omap_sham_dev	*dd;

	unsigned long		flags;

	/* fallback stuff */
	struct crypto_shash	*fallback;

	struct omap_sham_hmac_ctx base[0];
};

#define OMAP_SHAM_QUEUE_LENGTH	1

struct omap_sham_dev {
	struct list_head	list;
	unsigned long		phys_base;
	struct device		*dev;
	void __iomem		*io_base;
	int			irq;
	struct clk		*iclk;
	spinlock_t		lock;
	int			err;
	int			dma;
	int			dma_lch;
	struct tasklet_struct	done_task;

	unsigned long		flags;
	struct crypto_queue	queue;
	struct ahash_request	*req;
};

struct omap_sham_drv {
	struct list_head	dev_list;
	spinlock_t		lock;
	unsigned long		flags;
};

static struct omap_sham_drv sham = {
	.dev_list = LIST_HEAD_INIT(sham.dev_list),
	.lock = __SPIN_LOCK_UNLOCKED(sham.lock),
};

static inline u32 omap_sham_read(struct omap_sham_dev *dd, u32 offset)
{
	return __raw_readl(dd->io_base + offset);
}

static inline void omap_sham_write(struct omap_sham_dev *dd,
					u32 offset, u32 value)
{
	__raw_writel(value, dd->io_base + offset);
}

static inline void omap_sham_write_mask(struct omap_sham_dev *dd, u32 address,
					u32 value, u32 mask)
{
	u32 val;

	val = omap_sham_read(dd, address);
	val &= ~mask;
	val |= value;
	omap_sham_write(dd, address, val);
}

static inline int omap_sham_wait(struct omap_sham_dev *dd, u32 offset, u32 bit)
{
	unsigned long timeout = jiffies + DEFAULT_TIMEOUT_INTERVAL;

	while (!(omap_sham_read(dd, offset) & bit)) {
		if (time_is_before_jiffies(timeout))
			return -ETIMEDOUT;
	}

	return 0;
}

static void omap_sham_copy_hash(struct ahash_request *req, int out)
{
	struct omap_sham_reqctx *ctx = ahash_request_ctx(req);
	u32 *hash = (u32 *)ctx->digest;
	int i;

	/* MD5 is almost unused. So copy sha1 size to reduce code */
	for (i = 0; i < SHA1_DIGEST_SIZE / sizeof(u32); i++) {
		if (out)
			hash[i] = omap_sham_read(ctx->dd,
						SHA_REG_DIGEST(i));
		else
			omap_sham_write(ctx->dd,
					SHA_REG_DIGEST(i), hash[i]);
	}
}

static void omap_sham_copy_ready_hash(struct ahash_request *req)
{
	struct omap_sham_reqctx *ctx = ahash_request_ctx(req);
	u32 *in = (u32 *)ctx->digest;
	u32 *hash = (u32 *)req->result;
	int i;

	if (!hash)
		return;

	if (likely(ctx->flags & BIT(FLAGS_SHA1))) {
		/* SHA1 results are in big endian */
		for (i = 0; i < SHA1_DIGEST_SIZE / sizeof(u32); i++)
			hash[i] = be32_to_cpu(in[i]);
	} else {
		/* MD5 results are in little endian */
		for (i = 0; i < MD5_DIGEST_SIZE / sizeof(u32); i++)
			hash[i] = le32_to_cpu(in[i]);
	}
}

static int omap_sham_hw_init(struct omap_sham_dev *dd)
{
	clk_enable(dd->iclk);

	if (!test_bit(FLAGS_INIT, &dd->flags)) {
		omap_sham_write_mask(dd, SHA_REG_MASK,
			SHA_REG_MASK_SOFTRESET, SHA_REG_MASK_SOFTRESET);

		if (omap_sham_wait(dd, SHA_REG_SYSSTATUS,
					SHA_REG_SYSSTATUS_RESETDONE))
			return -ETIMEDOUT;

		set_bit(FLAGS_INIT, &dd->flags);
		dd->err = 0;
	}

	return 0;
}

static void omap_sham_write_ctrl(struct omap_sham_dev *dd, size_t length,
				 int final, int dma)
{
	struct omap_sham_reqctx *ctx = ahash_request_ctx(dd->req);
	u32 val = length << 5, mask;

	if (likely(ctx->digcnt))
		omap_sham_write(dd, SHA_REG_DIGCNT, ctx->digcnt);

	omap_sham_write_mask(dd, SHA_REG_MASK,
		SHA_REG_MASK_IT_EN | (dma ? SHA_REG_MASK_DMA_EN : 0),
		SHA_REG_MASK_IT_EN | SHA_REG_MASK_DMA_EN);
	/*
	 * Setting ALGO_CONST only for the first iteration
	 * and CLOSE_HASH only for the last one.
	 */
	if (ctx->flags & BIT(FLAGS_SHA1))
		val |= SHA_REG_CTRL_ALGO;
	if (!ctx->digcnt)
		val |= SHA_REG_CTRL_ALGO_CONST;
	if (final)
		val |= SHA_REG_CTRL_CLOSE_HASH;

	mask = SHA_REG_CTRL_ALGO_CONST | SHA_REG_CTRL_CLOSE_HASH |
			SHA_REG_CTRL_ALGO | SHA_REG_CTRL_LENGTH;

	omap_sham_write_mask(dd, SHA_REG_CTRL, val, mask);
}

static int omap_sham_xmit_cpu(struct omap_sham_dev *dd, const u8 *buf,
			      size_t length, int final)
{
	struct omap_sham_reqctx *ctx = ahash_request_ctx(dd->req);
	int count, len32;
	const u32 *buffer = (const u32 *)buf;

	dev_dbg(dd->dev, "xmit_cpu: digcnt: %d, length: %d, final: %d\n",
						ctx->digcnt, length, final);

	omap_sham_write_ctrl(dd, length, final, 0);

	/* should be non-zero before next lines to disable clocks later */
	ctx->digcnt += length;

	if (omap_sham_wait(dd, SHA_REG_CTRL, SHA_REG_CTRL_INPUT_READY))
		return -ETIMEDOUT;

	if (final)
		set_bit(FLAGS_FINAL, &dd->flags); /* catch last interrupt */

	set_bit(FLAGS_CPU, &dd->flags);

	len32 = DIV_ROUND_UP(length, sizeof(u32));

	for (count = 0; count < len32; count++)
		omap_sham_write(dd, SHA_REG_DIN(count), buffer[count]);

	return -EINPROGRESS;
}

static int omap_sham_xmit_dma(struct omap_sham_dev *dd, dma_addr_t dma_addr,
			      size_t length, int final)
{
	struct omap_sham_reqctx *ctx = ahash_request_ctx(dd->req);
	int len32;

	dev_dbg(dd->dev, "xmit_dma: digcnt: %d, length: %d, final: %d\n",
						ctx->digcnt, length, final);

	len32 = DIV_ROUND_UP(length, sizeof(u32));

	omap_set_dma_transfer_params(dd->dma_lch, OMAP_DMA_DATA_TYPE_S32, len32,
			1, OMAP_DMA_SYNC_PACKET, dd->dma,
				OMAP_DMA_DST_SYNC_PREFETCH);

	omap_set_dma_src_params(dd->dma_lch, 0, OMAP_DMA_AMODE_POST_INC,
				dma_addr, 0, 0);

	omap_sham_write_ctrl(dd, length, final, 1);

	ctx->digcnt += length;

	if (final)
		set_bit(FLAGS_FINAL, &dd->flags); /* catch last interrupt */

	set_bit(FLAGS_DMA_ACTIVE, &dd->flags);

	omap_start_dma(dd->dma_lch);

	return -EINPROGRESS;
}

static size_t omap_sham_append_buffer(struct omap_sham_reqctx *ctx,
				const u8 *data, size_t length)
{
	size_t count = min(length, ctx->buflen - ctx->bufcnt);

	count = min(count, ctx->total);
	if (count <= 0)
		return 0;
	memcpy(ctx->buffer + ctx->bufcnt, data, count);
	ctx->bufcnt += count;

	return count;
}

static size_t omap_sham_append_sg(struct omap_sham_reqctx *ctx)
{
	size_t count;

	while (ctx->sg) {
		count = omap_sham_append_buffer(ctx,
				sg_virt(ctx->sg) + ctx->offset,
				ctx->sg->length - ctx->offset);
		if (!count)
			break;
		ctx->offset += count;
		ctx->total -= count;
		if (ctx->offset == ctx->sg->length) {
			ctx->sg = sg_next(ctx->sg);
			if (ctx->sg)
				ctx->offset = 0;
			else
				ctx->total = 0;
		}
	}

	return 0;
}

static int omap_sham_xmit_dma_map(struct omap_sham_dev *dd,
					struct omap_sham_reqctx *ctx,
					size_t length, int final)
{
	ctx->dma_addr = dma_map_single(dd->dev, ctx->buffer, ctx->buflen,
				       DMA_TO_DEVICE);
	if (dma_mapping_error(dd->dev, ctx->dma_addr)) {
		dev_err(dd->dev, "dma %u bytes error\n", ctx->buflen);
		return -EINVAL;
	}

	ctx->flags &= ~BIT(FLAGS_SG);

	/* next call does not fail... so no unmap in the case of error */
	return omap_sham_xmit_dma(dd, ctx->dma_addr, length, final);
}

static int omap_sham_update_dma_slow(struct omap_sham_dev *dd)
{
	struct omap_sham_reqctx *ctx = ahash_request_ctx(dd->req);
	unsigned int final;
	size_t count;

	omap_sham_append_sg(ctx);

	final = (ctx->flags & BIT(FLAGS_FINUP)) && !ctx->total;

	dev_dbg(dd->dev, "slow: bufcnt: %u, digcnt: %d, final: %d\n",
					 ctx->bufcnt, ctx->digcnt, final);

	if (final || (ctx->bufcnt == ctx->buflen && ctx->total)) {
		count = ctx->bufcnt;
		ctx->bufcnt = 0;
		return omap_sham_xmit_dma_map(dd, ctx, count, final);
	}

	return 0;
}

/* Start address alignment */
#define SG_AA(sg)	(IS_ALIGNED(sg->offset, sizeof(u32)))
/* SHA1 block size alignment */
#define SG_SA(sg)	(IS_ALIGNED(sg->length, SHA1_MD5_BLOCK_SIZE))

static int omap_sham_update_dma_start(struct omap_sham_dev *dd)
{
	struct omap_sham_reqctx *ctx = ahash_request_ctx(dd->req);
	unsigned int length, final, tail;
	struct scatterlist *sg;

	if (!ctx->total)
		return 0;

	if (ctx->bufcnt || ctx->offset)
		return omap_sham_update_dma_slow(dd);

	dev_dbg(dd->dev, "fast: digcnt: %d, bufcnt: %u, total: %u\n",
			ctx->digcnt, ctx->bufcnt, ctx->total);

	sg = ctx->sg;

	if (!SG_AA(sg))
		return omap_sham_update_dma_slow(dd);

	if (!sg_is_last(sg) && !SG_SA(sg))
		/* size is not SHA1_BLOCK_SIZE aligned */
		return omap_sham_update_dma_slow(dd);

	length = min(ctx->total, sg->length);

	if (sg_is_last(sg)) {
		if (!(ctx->flags & BIT(FLAGS_FINUP))) {
			/* not last sg must be SHA1_MD5_BLOCK_SIZE aligned */
			tail = length & (SHA1_MD5_BLOCK_SIZE - 1);
			/* without finup() we need one block to close hash */
			if (!tail)
				tail = SHA1_MD5_BLOCK_SIZE;
			length -= tail;
		}
	}

	if (!dma_map_sg(dd->dev, ctx->sg, 1, DMA_TO_DEVICE)) {
		dev_err(dd->dev, "dma_map_sg  error\n");
		return -EINVAL;
	}

	ctx->flags |= BIT(FLAGS_SG);

	ctx->total -= length;
	ctx->offset = length; /* offset where to start slow */

	final = (ctx->flags & BIT(FLAGS_FINUP)) && !ctx->total;

	/* next call does not fail... so no unmap in the case of error */
	return omap_sham_xmit_dma(dd, sg_dma_address(ctx->sg), length, final);
}

static int omap_sham_update_cpu(struct omap_sham_dev *dd)
{
	struct omap_sham_reqctx *ctx = ahash_request_ctx(dd->req);
	int bufcnt;

	omap_sham_append_sg(ctx);
	bufcnt = ctx->bufcnt;
	ctx->bufcnt = 0;

	return omap_sham_xmit_cpu(dd, ctx->buffer, bufcnt, 1);
}

static int omap_sham_update_dma_stop(struct omap_sham_dev *dd)
{
	struct omap_sham_reqctx *ctx = ahash_request_ctx(dd->req);

	omap_stop_dma(dd->dma_lch);
	if (ctx->flags & BIT(FLAGS_SG)) {
		dma_unmap_sg(dd->dev, ctx->sg, 1, DMA_TO_DEVICE);
		if (ctx->sg->length == ctx->offset) {
			ctx->sg = sg_next(ctx->sg);
			if (ctx->sg)
				ctx->offset = 0;
		}
	} else {
		dma_unmap_single(dd->dev, ctx->dma_addr, ctx->buflen,
				 DMA_TO_DEVICE);
	}

	return 0;
}

static int omap_sham_init(struct ahash_request *req)
{
	struct crypto_ahash *tfm = crypto_ahash_reqtfm(req);
	struct omap_sham_ctx *tctx = crypto_ahash_ctx(tfm);
	struct omap_sham_reqctx *ctx = ahash_request_ctx(req);
	struct omap_sham_dev *dd = NULL, *tmp;

	spin_lock_bh(&sham.lock);
	if (!tctx->dd) {
		list_for_each_entry(tmp, &sham.dev_list, list) {
			dd = tmp;
			break;
		}
		tctx->dd = dd;
	} else {
		dd = tctx->dd;
	}
	spin_unlock_bh(&sham.lock);

	ctx->dd = dd;

	ctx->flags = 0;

	dev_dbg(dd->dev, "init: digest size: %d\n",
		crypto_ahash_digestsize(tfm));

	if (crypto_ahash_digestsize(tfm) == SHA1_DIGEST_SIZE)
		ctx->flags |= BIT(FLAGS_SHA1);

	ctx->bufcnt = 0;
	ctx->digcnt = 0;
	ctx->buflen = BUFLEN;

	if (tctx->flags & BIT(FLAGS_HMAC)) {
		struct omap_sham_hmac_ctx *bctx = tctx->base;

		memcpy(ctx->buffer, bctx->ipad, SHA1_MD5_BLOCK_SIZE);
		ctx->bufcnt = SHA1_MD5_BLOCK_SIZE;
		ctx->flags |= BIT(FLAGS_HMAC);
	}

	return 0;

}

static int omap_sham_update_req(struct omap_sham_dev *dd)
{
	struct ahash_request *req = dd->req;
	struct omap_sham_reqctx *ctx = ahash_request_ctx(req);
	int err;

	dev_dbg(dd->dev, "update_req: total: %u, digcnt: %d, finup: %d\n",
		 ctx->total, ctx->digcnt, (ctx->flags & BIT(FLAGS_FINUP)) != 0);

	if (ctx->flags & BIT(FLAGS_CPU))
		err = omap_sham_update_cpu(dd);
	else
		err = omap_sham_update_dma_start(dd);

	/* wait for dma completion before can take more data */
	dev_dbg(dd->dev, "update: err: %d, digcnt: %d\n", err, ctx->digcnt);

	return err;
}

static int omap_sham_final_req(struct omap_sham_dev *dd)
{
	struct ahash_request *req = dd->req;
	struct omap_sham_reqctx *ctx = ahash_request_ctx(req);
	int err = 0, use_dma = 1;

	if (ctx->bufcnt <= 64)
		/* faster to handle last block with cpu */
		use_dma = 0;

	if (use_dma)
		err = omap_sham_xmit_dma_map(dd, ctx, ctx->bufcnt, 1);
	else
		err = omap_sham_xmit_cpu(dd, ctx->buffer, ctx->bufcnt, 1);

	ctx->bufcnt = 0;

	dev_dbg(dd->dev, "final_req: err: %d\n", err);

	return err;
}

static int omap_sham_finish_hmac(struct ahash_request *req)
{
	struct omap_sham_ctx *tctx = crypto_tfm_ctx(req->base.tfm);
	struct omap_sham_hmac_ctx *bctx = tctx->base;
	int bs = crypto_shash_blocksize(bctx->shash);
	int ds = crypto_shash_digestsize(bctx->shash);
	struct {
		struct shash_desc shash;
		char ctx[crypto_shash_descsize(bctx->shash)];
	} desc;

	desc.shash.tfm = bctx->shash;
	desc.shash.flags = 0; /* not CRYPTO_TFM_REQ_MAY_SLEEP */

	return crypto_shash_init(&desc.shash) ?:
	       crypto_shash_update(&desc.shash, bctx->opad, bs) ?:
	       crypto_shash_finup(&desc.shash, req->result, ds, req->result);
}

static int omap_sham_finish(struct ahash_request *req)
{
	struct omap_sham_reqctx *ctx = ahash_request_ctx(req);
	struct omap_sham_dev *dd = ctx->dd;
	int err = 0;

	if (ctx->digcnt) {
		omap_sham_copy_ready_hash(req);
		if (ctx->flags & BIT(FLAGS_HMAC))
			err = omap_sham_finish_hmac(req);
	}

	dev_dbg(dd->dev, "digcnt: %d, bufcnt: %d\n", ctx->digcnt, ctx->bufcnt);

	return err;
}

static void omap_sham_finish_req(struct ahash_request *req, int err)
{
	struct omap_sham_reqctx *ctx = ahash_request_ctx(req);
	struct omap_sham_dev *dd = ctx->dd;

	if (!err) {
		omap_sham_copy_hash(req, 1);
		if (test_bit(FLAGS_FINAL, &dd->flags))
			err = omap_sham_finish(req);
	} else {
		ctx->flags |= BIT(FLAGS_ERROR);
	}

	/* atomic operation is not needed here */
	dd->flags &= ~(BIT(FLAGS_BUSY) | BIT(FLAGS_FINAL) | BIT(FLAGS_CPU) |
			BIT(FLAGS_DMA_READY) | BIT(FLAGS_OUTPUT_READY));
	clk_disable(dd->iclk);

	if (req->base.complete)
		req->base.complete(&req->base, err);

	/* handle new request */
	tasklet_schedule(&dd->done_task);
}

static int omap_sham_handle_queue(struct omap_sham_dev *dd,
				  struct ahash_request *req)
{
	struct crypto_async_request *async_req, *backlog;
	struct omap_sham_reqctx *ctx;
	unsigned long flags;
	int err = 0, ret = 0;

	spin_lock_irqsave(&dd->lock, flags);
	if (req)
		ret = ahash_enqueue_request(&dd->queue, req);
	if (test_bit(FLAGS_BUSY, &dd->flags)) {
		spin_unlock_irqrestore(&dd->lock, flags);
		return ret;
	}
	backlog = crypto_get_backlog(&dd->queue);
	async_req = crypto_dequeue_request(&dd->queue);
	if (async_req)
		set_bit(FLAGS_BUSY, &dd->flags);
	spin_unlock_irqrestore(&dd->lock, flags);

	if (!async_req)
		return ret;

	if (backlog)
		backlog->complete(backlog, -EINPROGRESS);

	req = ahash_request_cast(async_req);
	dd->req = req;
	ctx = ahash_request_ctx(req);

	dev_dbg(dd->dev, "handling new req, op: %lu, nbytes: %d\n",
						ctx->op, req->nbytes);

	err = omap_sham_hw_init(dd);
	if (err)
		goto err1;

	omap_set_dma_dest_params(dd->dma_lch, 0,
			OMAP_DMA_AMODE_CONSTANT,
			dd->phys_base + SHA_REG_DIN(0), 0, 16);

	omap_set_dma_dest_burst_mode(dd->dma_lch,
			OMAP_DMA_DATA_BURST_16);

	omap_set_dma_src_burst_mode(dd->dma_lch,
			OMAP_DMA_DATA_BURST_4);

	if (ctx->digcnt)
		/* request has changed - restore hash */
		omap_sham_copy_hash(req, 0);

	if (ctx->op == OP_UPDATE) {
		err = omap_sham_update_req(dd);
		if (err != -EINPROGRESS && (ctx->flags & BIT(FLAGS_FINUP)))
			/* no final() after finup() */
			err = omap_sham_final_req(dd);
	} else if (ctx->op == OP_FINAL) {
		err = omap_sham_final_req(dd);
	}
err1:
	if (err != -EINPROGRESS)
		/* done_task will not finish it, so do it here */
		omap_sham_finish_req(req, err);

	dev_dbg(dd->dev, "exit, err: %d\n", err);

	return ret;
}

static int omap_sham_enqueue(struct ahash_request *req, unsigned int op)
{
	struct omap_sham_reqctx *ctx = ahash_request_ctx(req);
	struct omap_sham_ctx *tctx = crypto_tfm_ctx(req->base.tfm);
	struct omap_sham_dev *dd = tctx->dd;

	ctx->op = op;

	return omap_sham_handle_queue(dd, req);
}

static int omap_sham_update(struct ahash_request *req)
{
	struct omap_sham_reqctx *ctx = ahash_request_ctx(req);

	if (!req->nbytes)
		return 0;

	ctx->total = req->nbytes;
	ctx->sg = req->src;
	ctx->offset = 0;

	if (ctx->flags & BIT(FLAGS_FINUP)) {
		if ((ctx->digcnt + ctx->bufcnt + ctx->total) < 9) {
			/*
			* OMAP HW accel works only with buffers >= 9
			* will switch to bypass in final()
			* final has the same request and data
			*/
			omap_sham_append_sg(ctx);
			return 0;
		} else if (ctx->bufcnt + ctx->total <= SHA1_MD5_BLOCK_SIZE) {
			/*
			* faster to use CPU for short transfers
			*/
			ctx->flags |= BIT(FLAGS_CPU);
		}
	} else if (ctx->bufcnt + ctx->total < ctx->buflen) {
		omap_sham_append_sg(ctx);
		return 0;
	}

	return omap_sham_enqueue(req, OP_UPDATE);
}

static int omap_sham_shash_digest(struct crypto_shash *shash, u32 flags,
				  const u8 *data, unsigned int len, u8 *out)
{
	struct {
		struct shash_desc shash;
		char ctx[crypto_shash_descsize(shash)];
	} desc;

	desc.shash.tfm = shash;
	desc.shash.flags = flags & CRYPTO_TFM_REQ_MAY_SLEEP;

	return crypto_shash_digest(&desc.shash, data, len, out);
}

static int omap_sham_final_shash(struct ahash_request *req)
{
	struct omap_sham_ctx *tctx = crypto_tfm_ctx(req->base.tfm);
	struct omap_sham_reqctx *ctx = ahash_request_ctx(req);

	return omap_sham_shash_digest(tctx->fallback, req->base.flags,
				      ctx->buffer, ctx->bufcnt, req->result);
}

static int omap_sham_final(struct ahash_request *req)
{
	struct omap_sham_reqctx *ctx = ahash_request_ctx(req);

	ctx->flags |= BIT(FLAGS_FINUP);

	if (ctx->flags & BIT(FLAGS_ERROR))
		return 0; /* uncompleted hash is not needed */

	/* OMAP HW accel works only with buffers >= 9 */
	/* HMAC is always >= 9 because ipad == block size */
	if ((ctx->digcnt + ctx->bufcnt) < 9)
		return omap_sham_final_shash(req);
	else if (ctx->bufcnt)
		return omap_sham_enqueue(req, OP_FINAL);

	/* copy ready hash (+ finalize hmac) */
	return omap_sham_finish(req);
}

static int omap_sham_finup(struct ahash_request *req)
{
	struct omap_sham_reqctx *ctx = ahash_request_ctx(req);
	int err1, err2;

	ctx->flags |= BIT(FLAGS_FINUP);

	err1 = omap_sham_update(req);
	if (err1 == -EINPROGRESS || err1 == -EBUSY)
		return err1;
	/*
	 * final() has to be always called to cleanup resources
	 * even if udpate() failed, except EINPROGRESS
	 */
	err2 = omap_sham_final(req);

	return err1 ?: err2;
}

static int omap_sham_digest(struct ahash_request *req)
{
	return omap_sham_init(req) ?: omap_sham_finup(req);
}

static int omap_sham_setkey(struct crypto_ahash *tfm, const u8 *key,
		      unsigned int keylen)
{
	struct omap_sham_ctx *tctx = crypto_ahash_ctx(tfm);
	struct omap_sham_hmac_ctx *bctx = tctx->base;
	int bs = crypto_shash_blocksize(bctx->shash);
	int ds = crypto_shash_digestsize(bctx->shash);
	int err, i;
	err = crypto_shash_setkey(tctx->fallback, key, keylen);
	if (err)
		return err;

	if (keylen > bs) {
		err = omap_sham_shash_digest(bctx->shash,
				crypto_shash_get_flags(bctx->shash),
				key, keylen, bctx->ipad);
		if (err)
			return err;
		keylen = ds;
	} else {
		memcpy(bctx->ipad, key, keylen);
	}

	memset(bctx->ipad + keylen, 0, bs - keylen);
	memcpy(bctx->opad, bctx->ipad, bs);

	for (i = 0; i < bs; i++) {
		bctx->ipad[i] ^= 0x36;
		bctx->opad[i] ^= 0x5c;
	}

	return err;
}

static int omap_sham_cra_init_alg(struct crypto_tfm *tfm, const char *alg_base)
{
	struct omap_sham_ctx *tctx = crypto_tfm_ctx(tfm);
	const char *alg_name = crypto_tfm_alg_name(tfm);

	/* Allocate a fallback and abort if it failed. */
	tctx->fallback = crypto_alloc_shash(alg_name, 0,
					    CRYPTO_ALG_NEED_FALLBACK);
	if (IS_ERR(tctx->fallback)) {
		pr_err("omap-sham: fallback driver '%s' "
				"could not be loaded.\n", alg_name);
		return PTR_ERR(tctx->fallback);
	}

	crypto_ahash_set_reqsize(__crypto_ahash_cast(tfm),
				 sizeof(struct omap_sham_reqctx) + BUFLEN);

	if (alg_base) {
		struct omap_sham_hmac_ctx *bctx = tctx->base;
		tctx->flags |= BIT(FLAGS_HMAC);
		bctx->shash = crypto_alloc_shash(alg_base, 0,
						CRYPTO_ALG_NEED_FALLBACK);
		if (IS_ERR(bctx->shash)) {
			pr_err("omap-sham: base driver '%s' "
					"could not be loaded.\n", alg_base);
			crypto_free_shash(tctx->fallback);
			return PTR_ERR(bctx->shash);
		}

	}

	return 0;
}

static int omap_sham_cra_init(struct crypto_tfm *tfm)
{
	return omap_sham_cra_init_alg(tfm, NULL);
}

static int omap_sham_cra_sha1_init(struct crypto_tfm *tfm)
{
	return omap_sham_cra_init_alg(tfm, "sha1");
}

static int omap_sham_cra_md5_init(struct crypto_tfm *tfm)
{
	return omap_sham_cra_init_alg(tfm, "md5");
}

static void omap_sham_cra_exit(struct crypto_tfm *tfm)
{
	struct omap_sham_ctx *tctx = crypto_tfm_ctx(tfm);

	crypto_free_shash(tctx->fallback);
	tctx->fallback = NULL;

	if (tctx->flags & BIT(FLAGS_HMAC)) {
		struct omap_sham_hmac_ctx *bctx = tctx->base;
		crypto_free_shash(bctx->shash);
	}
}

static struct ahash_alg algs[] = {
{
	.init		= omap_sham_init,
	.update		= omap_sham_update,
	.final		= omap_sham_final,
	.finup		= omap_sham_finup,
	.digest		= omap_sham_digest,
	.halg.digestsize	= SHA1_DIGEST_SIZE,
	.halg.base	= {
		.cra_name		= "sha1",
		.cra_driver_name	= "omap-sha1",
		.cra_priority		= 100,
		.cra_flags		= CRYPTO_ALG_TYPE_AHASH |
						CRYPTO_ALG_KERN_DRIVER_ONLY |
						CRYPTO_ALG_ASYNC |
						CRYPTO_ALG_NEED_FALLBACK,
		.cra_blocksize		= SHA1_BLOCK_SIZE,
		.cra_ctxsize		= sizeof(struct omap_sham_ctx),
		.cra_alignmask		= 0,
		.cra_module		= THIS_MODULE,
		.cra_init		= omap_sham_cra_init,
		.cra_exit		= omap_sham_cra_exit,
	}
},
{
	.init		= omap_sham_init,
	.update		= omap_sham_update,
	.final		= omap_sham_final,
	.finup		= omap_sham_finup,
	.digest		= omap_sham_digest,
	.halg.digestsize	= MD5_DIGEST_SIZE,
	.halg.base	= {
		.cra_name		= "md5",
		.cra_driver_name	= "omap-md5",
		.cra_priority		= 100,
		.cra_flags		= CRYPTO_ALG_TYPE_AHASH |
						CRYPTO_ALG_KERN_DRIVER_ONLY |
						CRYPTO_ALG_ASYNC |
						CRYPTO_ALG_NEED_FALLBACK,
		.cra_blocksize		= SHA1_BLOCK_SIZE,
		.cra_ctxsize		= sizeof(struct omap_sham_ctx),
		.cra_alignmask		= OMAP_ALIGN_MASK,
		.cra_module		= THIS_MODULE,
		.cra_init		= omap_sham_cra_init,
		.cra_exit		= omap_sham_cra_exit,
	}
},
{
	.init		= omap_sham_init,
	.update		= omap_sham_update,
	.final		= omap_sham_final,
	.finup		= omap_sham_finup,
	.digest		= omap_sham_digest,
	.setkey		= omap_sham_setkey,
	.halg.digestsize	= SHA1_DIGEST_SIZE,
	.halg.base	= {
		.cra_name		= "hmac(sha1)",
		.cra_driver_name	= "omap-hmac-sha1",
		.cra_priority		= 100,
		.cra_flags		= CRYPTO_ALG_TYPE_AHASH |
						CRYPTO_ALG_KERN_DRIVER_ONLY |
						CRYPTO_ALG_ASYNC |
						CRYPTO_ALG_NEED_FALLBACK,
		.cra_blocksize		= SHA1_BLOCK_SIZE,
		.cra_ctxsize		= sizeof(struct omap_sham_ctx) +
					sizeof(struct omap_sham_hmac_ctx),
		.cra_alignmask		= OMAP_ALIGN_MASK,
		.cra_module		= THIS_MODULE,
		.cra_init		= omap_sham_cra_sha1_init,
		.cra_exit		= omap_sham_cra_exit,
	}
},
{
	.init		= omap_sham_init,
	.update		= omap_sham_update,
	.final		= omap_sham_final,
	.finup		= omap_sham_finup,
	.digest		= omap_sham_digest,
	.setkey		= omap_sham_setkey,
	.halg.digestsize	= MD5_DIGEST_SIZE,
	.halg.base	= {
		.cra_name		= "hmac(md5)",
		.cra_driver_name	= "omap-hmac-md5",
		.cra_priority		= 100,
		.cra_flags		= CRYPTO_ALG_TYPE_AHASH |
						CRYPTO_ALG_KERN_DRIVER_ONLY |
						CRYPTO_ALG_ASYNC |
						CRYPTO_ALG_NEED_FALLBACK,
		.cra_blocksize		= SHA1_BLOCK_SIZE,
		.cra_ctxsize		= sizeof(struct omap_sham_ctx) +
					sizeof(struct omap_sham_hmac_ctx),
		.cra_alignmask		= OMAP_ALIGN_MASK,
		.cra_module		= THIS_MODULE,
		.cra_init		= omap_sham_cra_md5_init,
		.cra_exit		= omap_sham_cra_exit,
	}
}
};

static void omap_sham_done_task(unsigned long data)
{
	struct omap_sham_dev *dd = (struct omap_sham_dev *)data;
	int err = 0;

	if (!test_bit(FLAGS_BUSY, &dd->flags)) {
		omap_sham_handle_queue(dd, NULL);
		return;
	}

	if (test_bit(FLAGS_CPU, &dd->flags)) {
		if (test_and_clear_bit(FLAGS_OUTPUT_READY, &dd->flags))
			goto finish;
	} else if (test_bit(FLAGS_DMA_READY, &dd->flags)) {
		if (test_and_clear_bit(FLAGS_DMA_ACTIVE, &dd->flags)) {
			omap_sham_update_dma_stop(dd);
			if (dd->err) {
				err = dd->err;
				goto finish;
			}
		}
		if (test_and_clear_bit(FLAGS_OUTPUT_READY, &dd->flags)) {
			/* hash or semi-hash ready */
			clear_bit(FLAGS_DMA_READY, &dd->flags);
			err = omap_sham_update_dma_start(dd);
			if (err != -EINPROGRESS)
				goto finish;
		}
	}

	return;

finish:
	dev_dbg(dd->dev, "update done: err: %d\n", err);
	/* finish curent request */
	omap_sham_finish_req(dd->req, err);
}

static irqreturn_t omap_sham_irq(int irq, void *dev_id)
{
	struct omap_sham_dev *dd = dev_id;

	if (unlikely(test_bit(FLAGS_FINAL, &dd->flags)))
		/* final -> allow device to go to power-saving mode */
		omap_sham_write_mask(dd, SHA_REG_CTRL, 0, SHA_REG_CTRL_LENGTH);

	omap_sham_write_mask(dd, SHA_REG_CTRL, SHA_REG_CTRL_OUTPUT_READY,
				 SHA_REG_CTRL_OUTPUT_READY);
	omap_sham_read(dd, SHA_REG_CTRL);

	if (!test_bit(FLAGS_BUSY, &dd->flags)) {
		dev_warn(dd->dev, "Interrupt when no active requests.\n");
		return IRQ_HANDLED;
	}

	set_bit(FLAGS_OUTPUT_READY, &dd->flags);
	tasklet_schedule(&dd->done_task);

	return IRQ_HANDLED;
}

static void omap_sham_dma_callback(int lch, u16 ch_status, void *data)
{
	struct omap_sham_dev *dd = data;

	if (ch_status != OMAP_DMA_BLOCK_IRQ) {
		pr_err("omap-sham DMA error status: 0x%hx\n", ch_status);
		dd->err = -EIO;
		clear_bit(FLAGS_INIT, &dd->flags);/* request to re-initialize */
	}

	set_bit(FLAGS_DMA_READY, &dd->flags);
	tasklet_schedule(&dd->done_task);
}

static int omap_sham_dma_init(struct omap_sham_dev *dd)
{
	int err;

	dd->dma_lch = -1;

	err = omap_request_dma(dd->dma, dev_name(dd->dev),
			omap_sham_dma_callback, dd, &dd->dma_lch);
	if (err) {
		dev_err(dd->dev, "Unable to request DMA channel\n");
		return err;
	}

	return 0;
}

static void omap_sham_dma_cleanup(struct omap_sham_dev *dd)
{
	if (dd->dma_lch >= 0) {
		omap_free_dma(dd->dma_lch);
		dd->dma_lch = -1;
	}
}

static int __devinit omap_sham_probe(struct platform_device *pdev)
{
	struct omap_sham_dev *dd;
	struct device *dev = &pdev->dev;
	struct resource *res;
	int err, i, j;

	dd = kzalloc(sizeof(struct omap_sham_dev), GFP_KERNEL);
	if (dd == NULL) {
		dev_err(dev, "unable to alloc data struct.\n");
		err = -ENOMEM;
		goto data_err;
	}
	dd->dev = dev;
	platform_set_drvdata(pdev, dd);

	INIT_LIST_HEAD(&dd->list);
	spin_lock_init(&dd->lock);
	tasklet_init(&dd->done_task, omap_sham_done_task, (unsigned long)dd);
	crypto_init_queue(&dd->queue, OMAP_SHAM_QUEUE_LENGTH);

	dd->irq = -1;

	/* Get the base address */
	res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
	if (!res) {
		dev_err(dev, "no MEM resource info\n");
		err = -ENODEV;
		goto res_err;
	}
	dd->phys_base = res->start;

	/* Get the DMA */
	res = platform_get_resource(pdev, IORESOURCE_DMA, 0);
	if (!res) {
		dev_err(dev, "no DMA resource info\n");
		err = -ENODEV;
		goto res_err;
	}
	dd->dma = res->start;

	/* Get the IRQ */
	dd->irq = platform_get_irq(pdev,  0);
	if (dd->irq < 0) {
		dev_err(dev, "no IRQ resource info\n");
		err = dd->irq;
		goto res_err;
	}

	err = request_irq(dd->irq, omap_sham_irq,
			IRQF_TRIGGER_LOW, dev_name(dev), dd);
	if (err) {
		dev_err(dev, "unable to request irq.\n");
		goto res_err;
	}

	err = omap_sham_dma_init(dd);
	if (err)
		goto dma_err;

	/* Initializing the clock */
	dd->iclk = clk_get(dev, "ick");
	if (IS_ERR(dd->iclk)) {
		dev_err(dev, "clock intialization failed.\n");
		err = PTR_ERR(dd->iclk);
		goto clk_err;
	}

	dd->io_base = ioremap(dd->phys_base, SZ_4K);
	if (!dd->io_base) {
		dev_err(dev, "can't ioremap\n");
		err = -ENOMEM;
		goto io_err;
	}

	clk_enable(dd->iclk);
	dev_info(dev, "hw accel on OMAP rev %u.%u\n",
		(omap_sham_read(dd, SHA_REG_REV) & SHA_REG_REV_MAJOR) >> 4,
		omap_sham_read(dd, SHA_REG_REV) & SHA_REG_REV_MINOR);
	clk_disable(dd->iclk);

	spin_lock(&sham.lock);
	list_add_tail(&dd->list, &sham.dev_list);
	spin_unlock(&sham.lock);

	for (i = 0; i < ARRAY_SIZE(algs); i++) {
		err = crypto_register_ahash(&algs[i]);
		if (err)
			goto err_algs;
	}

	return 0;

err_algs:
	for (j = 0; j < i; j++)
		crypto_unregister_ahash(&algs[j]);
	iounmap(dd->io_base);
io_err:
	clk_put(dd->iclk);
clk_err:
	omap_sham_dma_cleanup(dd);
dma_err:
	if (dd->irq >= 0)
		free_irq(dd->irq, dd);
res_err:
	kfree(dd);
	dd = NULL;
data_err:
	dev_err(dev, "initialization failed.\n");

	return err;
}

static int __devexit omap_sham_remove(struct platform_device *pdev)
{
	static struct omap_sham_dev *dd;
	int i;

	dd = platform_get_drvdata(pdev);
	if (!dd)
		return -ENODEV;
	spin_lock(&sham.lock);
	list_del(&dd->list);
	spin_unlock(&sham.lock);
	for (i = 0; i < ARRAY_SIZE(algs); i++)
		crypto_unregister_ahash(&algs[i]);
	tasklet_kill(&dd->done_task);
	iounmap(dd->io_base);
	clk_put(dd->iclk);
	omap_sham_dma_cleanup(dd);
	if (dd->irq >= 0)
		free_irq(dd->irq, dd);
	kfree(dd);
	dd = NULL;

	return 0;
}

static struct platform_driver omap_sham_driver = {
	.probe	= omap_sham_probe,
	.remove	= omap_sham_remove,
	.driver	= {
		.name	= "omap-sham",
		.owner	= THIS_MODULE,
	},
};

static int __init omap_sham_mod_init(void)
{
	pr_info("loading %s driver\n", "omap-sham");

	return platform_driver_register(&omap_sham_driver);
}

static void __exit omap_sham_mod_exit(void)
{
	platform_driver_unregister(&omap_sham_driver);
}

module_init(omap_sham_mod_init);
module_exit(omap_sham_mod_exit);

MODULE_DESCRIPTION("OMAP SHA1/MD5 hw acceleration support.");
MODULE_LICENSE("GPL v2");
MODULE_AUTHOR("Dmitry Kasatkin");