summaryrefslogtreecommitdiffstats
path: root/drivers/mtd/nand/mxc_nand.c
blob: 3c4c0533191d5e59c7546f81f2465719e8b4ee99 (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
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
/*
 * Copyright 2004-2007 Freescale Semiconductor, Inc. All Rights Reserved.
 * Copyright 2008 Sascha Hauer, kernel@pengutronix.de
 *
 * 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.
 * This program is distributed in the hope that it will be useful,
 * but WITHOUT ANY WARRANTY; without even the implied warranty of
 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
 * GNU General Public License for more details.
 *
 * You should have received a copy of the GNU General Public License
 * along with this program; if not, write to the Free Software
 * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston,
 * MA 02110-1301, USA.
 */

#include <linux/delay.h>
#include <linux/slab.h>
#include <linux/init.h>
#include <linux/module.h>
#include <linux/mtd/mtd.h>
#include <linux/mtd/nand.h>
#include <linux/mtd/partitions.h>
#include <linux/interrupt.h>
#include <linux/device.h>
#include <linux/platform_device.h>
#include <linux/clk.h>
#include <linux/err.h>
#include <linux/io.h>
#include <linux/irq.h>
#include <linux/completion.h>

#include <asm/mach/flash.h>
#include <mach/mxc_nand.h>
#include <mach/hardware.h>

#define DRIVER_NAME "mxc_nand"

#define nfc_is_v21()		(cpu_is_mx25() || cpu_is_mx35())
#define nfc_is_v1()		(cpu_is_mx31() || cpu_is_mx27() || cpu_is_mx21())
#define nfc_is_v3_2()		(cpu_is_mx51() || cpu_is_mx53())
#define nfc_is_v3()		nfc_is_v3_2()

/* Addresses for NFC registers */
#define NFC_V1_V2_BUF_SIZE		(host->regs + 0x00)
#define NFC_V1_V2_BUF_ADDR		(host->regs + 0x04)
#define NFC_V1_V2_FLASH_ADDR		(host->regs + 0x06)
#define NFC_V1_V2_FLASH_CMD		(host->regs + 0x08)
#define NFC_V1_V2_CONFIG		(host->regs + 0x0a)
#define NFC_V1_V2_ECC_STATUS_RESULT	(host->regs + 0x0c)
#define NFC_V1_V2_RSLTMAIN_AREA		(host->regs + 0x0e)
#define NFC_V1_V2_RSLTSPARE_AREA	(host->regs + 0x10)
#define NFC_V1_V2_WRPROT		(host->regs + 0x12)
#define NFC_V1_UNLOCKSTART_BLKADDR	(host->regs + 0x14)
#define NFC_V1_UNLOCKEND_BLKADDR	(host->regs + 0x16)
#define NFC_V21_UNLOCKSTART_BLKADDR0	(host->regs + 0x20)
#define NFC_V21_UNLOCKSTART_BLKADDR1	(host->regs + 0x24)
#define NFC_V21_UNLOCKSTART_BLKADDR2	(host->regs + 0x28)
#define NFC_V21_UNLOCKSTART_BLKADDR3	(host->regs + 0x2c)
#define NFC_V21_UNLOCKEND_BLKADDR0	(host->regs + 0x22)
#define NFC_V21_UNLOCKEND_BLKADDR1	(host->regs + 0x26)
#define NFC_V21_UNLOCKEND_BLKADDR2	(host->regs + 0x2a)
#define NFC_V21_UNLOCKEND_BLKADDR3	(host->regs + 0x2e)
#define NFC_V1_V2_NF_WRPRST		(host->regs + 0x18)
#define NFC_V1_V2_CONFIG1		(host->regs + 0x1a)
#define NFC_V1_V2_CONFIG2		(host->regs + 0x1c)

#define NFC_V2_CONFIG1_ECC_MODE_4	(1 << 0)
#define NFC_V1_V2_CONFIG1_SP_EN		(1 << 2)
#define NFC_V1_V2_CONFIG1_ECC_EN	(1 << 3)
#define NFC_V1_V2_CONFIG1_INT_MSK	(1 << 4)
#define NFC_V1_V2_CONFIG1_BIG		(1 << 5)
#define NFC_V1_V2_CONFIG1_RST		(1 << 6)
#define NFC_V1_V2_CONFIG1_CE		(1 << 7)
#define NFC_V2_CONFIG1_ONE_CYCLE	(1 << 8)
#define NFC_V2_CONFIG1_PPB(x)		(((x) & 0x3) << 9)
#define NFC_V2_CONFIG1_FP_INT		(1 << 11)

#define NFC_V1_V2_CONFIG2_INT		(1 << 15)

/*
 * Operation modes for the NFC. Valid for v1, v2 and v3
 * type controllers.
 */
#define NFC_CMD				(1 << 0)
#define NFC_ADDR			(1 << 1)
#define NFC_INPUT			(1 << 2)
#define NFC_OUTPUT			(1 << 3)
#define NFC_ID				(1 << 4)
#define NFC_STATUS			(1 << 5)

#define NFC_V3_FLASH_CMD		(host->regs_axi + 0x00)
#define NFC_V3_FLASH_ADDR0		(host->regs_axi + 0x04)

#define NFC_V3_CONFIG1			(host->regs_axi + 0x34)
#define NFC_V3_CONFIG1_SP_EN		(1 << 0)
#define NFC_V3_CONFIG1_RBA(x)		(((x) & 0x7 ) << 4)

#define NFC_V3_ECC_STATUS_RESULT	(host->regs_axi + 0x38)

#define NFC_V3_LAUNCH			(host->regs_axi + 0x40)

#define NFC_V3_WRPROT			(host->regs_ip + 0x0)
#define NFC_V3_WRPROT_LOCK_TIGHT	(1 << 0)
#define NFC_V3_WRPROT_LOCK		(1 << 1)
#define NFC_V3_WRPROT_UNLOCK		(1 << 2)
#define NFC_V3_WRPROT_BLS_UNLOCK	(2 << 6)

#define NFC_V3_WRPROT_UNLOCK_BLK_ADD0   (host->regs_ip + 0x04)

#define NFC_V3_CONFIG2			(host->regs_ip + 0x24)
#define NFC_V3_CONFIG2_PS_512			(0 << 0)
#define NFC_V3_CONFIG2_PS_2048			(1 << 0)
#define NFC_V3_CONFIG2_PS_4096			(2 << 0)
#define NFC_V3_CONFIG2_ONE_CYCLE		(1 << 2)
#define NFC_V3_CONFIG2_ECC_EN			(1 << 3)
#define NFC_V3_CONFIG2_2CMD_PHASES		(1 << 4)
#define NFC_V3_CONFIG2_NUM_ADDR_PHASE0		(1 << 5)
#define NFC_V3_CONFIG2_ECC_MODE_8		(1 << 6)
#define NFC_V3_CONFIG2_PPB(x)			(((x) & 0x3) << 7)
#define NFC_V3_CONFIG2_NUM_ADDR_PHASE1(x)	(((x) & 0x3) << 12)
#define NFC_V3_CONFIG2_INT_MSK			(1 << 15)
#define NFC_V3_CONFIG2_ST_CMD(x)		(((x) & 0xff) << 24)
#define NFC_V3_CONFIG2_SPAS(x)			(((x) & 0xff) << 16)

#define NFC_V3_CONFIG3				(host->regs_ip + 0x28)
#define NFC_V3_CONFIG3_ADD_OP(x)		(((x) & 0x3) << 0)
#define NFC_V3_CONFIG3_FW8			(1 << 3)
#define NFC_V3_CONFIG3_SBB(x)			(((x) & 0x7) << 8)
#define NFC_V3_CONFIG3_NUM_OF_DEVICES(x)	(((x) & 0x7) << 12)
#define NFC_V3_CONFIG3_RBB_MODE			(1 << 15)
#define NFC_V3_CONFIG3_NO_SDMA			(1 << 20)

#define NFC_V3_IPC			(host->regs_ip + 0x2C)
#define NFC_V3_IPC_CREQ			(1 << 0)
#define NFC_V3_IPC_INT			(1 << 31)

#define NFC_V3_DELAY_LINE		(host->regs_ip + 0x34)

struct mxc_nand_host {
	struct mtd_info		mtd;
	struct nand_chip	nand;
	struct device		*dev;

	void			*spare0;
	void			*main_area0;

	void __iomem		*base;
	void __iomem		*regs;
	void __iomem		*regs_axi;
	void __iomem		*regs_ip;
	int			status_request;
	struct clk		*clk;
	int			clk_act;
	int			irq;
	int			eccsize;
	int			active_cs;

	struct completion	op_completion;

	uint8_t			*data_buf;
	unsigned int		buf_start;
	int			spare_len;

	void			(*preset)(struct mtd_info *);
	void			(*send_cmd)(struct mxc_nand_host *, uint16_t, int);
	void			(*send_addr)(struct mxc_nand_host *, uint16_t, int);
	void			(*send_page)(struct mtd_info *, unsigned int);
	void			(*send_read_id)(struct mxc_nand_host *);
	uint16_t		(*get_dev_status)(struct mxc_nand_host *);
	int			(*check_int)(struct mxc_nand_host *);
	void			(*irq_control)(struct mxc_nand_host *, int);
};

/* OOB placement block for use with hardware ecc generation */
static struct nand_ecclayout nandv1_hw_eccoob_smallpage = {
	.eccbytes = 5,
	.eccpos = {6, 7, 8, 9, 10},
	.oobfree = {{0, 5}, {12, 4}, }
};

static struct nand_ecclayout nandv1_hw_eccoob_largepage = {
	.eccbytes = 20,
	.eccpos = {6, 7, 8, 9, 10, 22, 23, 24, 25, 26,
		   38, 39, 40, 41, 42, 54, 55, 56, 57, 58},
	.oobfree = {{2, 4}, {11, 10}, {27, 10}, {43, 10}, {59, 5}, }
};

/* OOB description for 512 byte pages with 16 byte OOB */
static struct nand_ecclayout nandv2_hw_eccoob_smallpage = {
	.eccbytes = 1 * 9,
	.eccpos = {
		 7,  8,  9, 10, 11, 12, 13, 14, 15
	},
	.oobfree = {
		{.offset = 0, .length = 5}
	}
};

/* OOB description for 2048 byte pages with 64 byte OOB */
static struct nand_ecclayout nandv2_hw_eccoob_largepage = {
	.eccbytes = 4 * 9,
	.eccpos = {
		 7,  8,  9, 10, 11, 12, 13, 14, 15,
		23, 24, 25, 26, 27, 28, 29, 30, 31,
		39, 40, 41, 42, 43, 44, 45, 46, 47,
		55, 56, 57, 58, 59, 60, 61, 62, 63
	},
	.oobfree = {
		{.offset = 2, .length = 4},
		{.offset = 16, .length = 7},
		{.offset = 32, .length = 7},
		{.offset = 48, .length = 7}
	}
};

/* OOB description for 4096 byte pages with 128 byte OOB */
static struct nand_ecclayout nandv2_hw_eccoob_4k = {
	.eccbytes = 8 * 9,
	.eccpos = {
		7,  8,  9, 10, 11, 12, 13, 14, 15,
		23, 24, 25, 26, 27, 28, 29, 30, 31,
		39, 40, 41, 42, 43, 44, 45, 46, 47,
		55, 56, 57, 58, 59, 60, 61, 62, 63,
		71, 72, 73, 74, 75, 76, 77, 78, 79,
		87, 88, 89, 90, 91, 92, 93, 94, 95,
		103, 104, 105, 106, 107, 108, 109, 110, 111,
		119, 120, 121, 122, 123, 124, 125, 126, 127,
	},
	.oobfree = {
		{.offset = 2, .length = 4},
		{.offset = 16, .length = 7},
		{.offset = 32, .length = 7},
		{.offset = 48, .length = 7},
		{.offset = 64, .length = 7},
		{.offset = 80, .length = 7},
		{.offset = 96, .length = 7},
		{.offset = 112, .length = 7},
	}
};

static const char *part_probes[] = { "RedBoot", "cmdlinepart", NULL };

static irqreturn_t mxc_nfc_irq(int irq, void *dev_id)
{
	struct mxc_nand_host *host = dev_id;

	if (!host->check_int(host))
		return IRQ_NONE;

	host->irq_control(host, 0);

	complete(&host->op_completion);

	return IRQ_HANDLED;
}

static int check_int_v3(struct mxc_nand_host *host)
{
	uint32_t tmp;

	tmp = readl(NFC_V3_IPC);
	if (!(tmp & NFC_V3_IPC_INT))
		return 0;

	tmp &= ~NFC_V3_IPC_INT;
	writel(tmp, NFC_V3_IPC);

	return 1;
}

static int check_int_v1_v2(struct mxc_nand_host *host)
{
	uint32_t tmp;

	tmp = readw(NFC_V1_V2_CONFIG2);
	if (!(tmp & NFC_V1_V2_CONFIG2_INT))
		return 0;

	if (!cpu_is_mx21())
		writew(tmp & ~NFC_V1_V2_CONFIG2_INT, NFC_V1_V2_CONFIG2);

	return 1;
}

/*
 * It has been observed that the i.MX21 cannot read the CONFIG2:INT bit
 * if interrupts are masked (CONFIG1:INT_MSK is set). To handle this, the
 * driver can enable/disable the irq line rather than simply masking the
 * interrupts.
 */
static void irq_control_mx21(struct mxc_nand_host *host, int activate)
{
	if (activate)
		enable_irq(host->irq);
	else
		disable_irq_nosync(host->irq);
}

static void irq_control_v1_v2(struct mxc_nand_host *host, int activate)
{
	uint16_t tmp;

	tmp = readw(NFC_V1_V2_CONFIG1);

	if (activate)
		tmp &= ~NFC_V1_V2_CONFIG1_INT_MSK;
	else
		tmp |= NFC_V1_V2_CONFIG1_INT_MSK;

	writew(tmp, NFC_V1_V2_CONFIG1);
}

static void irq_control_v3(struct mxc_nand_host *host, int activate)
{
	uint32_t tmp;

	tmp = readl(NFC_V3_CONFIG2);

	if (activate)
		tmp &= ~NFC_V3_CONFIG2_INT_MSK;
	else
		tmp |= NFC_V3_CONFIG2_INT_MSK;

	writel(tmp, NFC_V3_CONFIG2);
}

/* This function polls the NANDFC to wait for the basic operation to
 * complete by checking the INT bit of config2 register.
 */
static void wait_op_done(struct mxc_nand_host *host, int useirq)
{
	int max_retries = 8000;

	if (useirq) {
		if (!host->check_int(host)) {
			INIT_COMPLETION(host->op_completion);
			host->irq_control(host, 1);
			wait_for_completion(&host->op_completion);
		}
	} else {
		while (max_retries-- > 0) {
			if (host->check_int(host))
				break;

			udelay(1);
		}
		if (max_retries < 0)
			pr_debug("%s: INT not set\n", __func__);
	}
}

static void send_cmd_v3(struct mxc_nand_host *host, uint16_t cmd, int useirq)
{
	/* fill command */
	writel(cmd, NFC_V3_FLASH_CMD);

	/* send out command */
	writel(NFC_CMD, NFC_V3_LAUNCH);

	/* Wait for operation to complete */
	wait_op_done(host, useirq);
}

/* This function issues the specified command to the NAND device and
 * waits for completion. */
static void send_cmd_v1_v2(struct mxc_nand_host *host, uint16_t cmd, int useirq)
{
	pr_debug("send_cmd(host, 0x%x, %d)\n", cmd, useirq);

	writew(cmd, NFC_V1_V2_FLASH_CMD);
	writew(NFC_CMD, NFC_V1_V2_CONFIG2);

	if (cpu_is_mx21() && (cmd == NAND_CMD_RESET)) {
		int max_retries = 100;
		/* Reset completion is indicated by NFC_CONFIG2 */
		/* being set to 0 */
		while (max_retries-- > 0) {
			if (readw(NFC_V1_V2_CONFIG2) == 0) {
				break;
			}
			udelay(1);
		}
		if (max_retries < 0)
			pr_debug("%s: RESET failed\n", __func__);
	} else {
		/* Wait for operation to complete */
		wait_op_done(host, useirq);
	}
}

static void send_addr_v3(struct mxc_nand_host *host, uint16_t addr, int islast)
{
	/* fill address */
	writel(addr, NFC_V3_FLASH_ADDR0);

	/* send out address */
	writel(NFC_ADDR, NFC_V3_LAUNCH);

	wait_op_done(host, 0);
}

/* This function sends an address (or partial address) to the
 * NAND device. The address is used to select the source/destination for
 * a NAND command. */
static void send_addr_v1_v2(struct mxc_nand_host *host, uint16_t addr, int islast)
{
	pr_debug("send_addr(host, 0x%x %d)\n", addr, islast);

	writew(addr, NFC_V1_V2_FLASH_ADDR);
	writew(NFC_ADDR, NFC_V1_V2_CONFIG2);

	/* Wait for operation to complete */
	wait_op_done(host, islast);
}

static void send_page_v3(struct mtd_info *mtd, unsigned int ops)
{
	struct nand_chip *nand_chip = mtd->priv;
	struct mxc_nand_host *host = nand_chip->priv;
	uint32_t tmp;

	tmp = readl(NFC_V3_CONFIG1);
	tmp &= ~(7 << 4);
	writel(tmp, NFC_V3_CONFIG1);

	/* transfer data from NFC ram to nand */
	writel(ops, NFC_V3_LAUNCH);

	wait_op_done(host, false);
}

static void send_page_v1_v2(struct mtd_info *mtd, unsigned int ops)
{
	struct nand_chip *nand_chip = mtd->priv;
	struct mxc_nand_host *host = nand_chip->priv;
	int bufs, i;

	if (nfc_is_v1() && mtd->writesize > 512)
		bufs = 4;
	else
		bufs = 1;

	for (i = 0; i < bufs; i++) {

		/* NANDFC buffer 0 is used for page read/write */
		writew((host->active_cs << 4) | i, NFC_V1_V2_BUF_ADDR);

		writew(ops, NFC_V1_V2_CONFIG2);

		/* Wait for operation to complete */
		wait_op_done(host, true);
	}
}

static void send_read_id_v3(struct mxc_nand_host *host)
{
	/* Read ID into main buffer */
	writel(NFC_ID, NFC_V3_LAUNCH);

	wait_op_done(host, true);

	memcpy(host->data_buf, host->main_area0, 16);
}

/* Request the NANDFC to perform a read of the NAND device ID. */
static void send_read_id_v1_v2(struct mxc_nand_host *host)
{
	struct nand_chip *this = &host->nand;

	/* NANDFC buffer 0 is used for device ID output */
	writew(host->active_cs << 4, NFC_V1_V2_BUF_ADDR);

	writew(NFC_ID, NFC_V1_V2_CONFIG2);

	/* Wait for operation to complete */
	wait_op_done(host, true);

	memcpy(host->data_buf, host->main_area0, 16);

	if (this->options & NAND_BUSWIDTH_16) {
		/* compress the ID info */
		host->data_buf[1] = host->data_buf[2];
		host->data_buf[2] = host->data_buf[4];
		host->data_buf[3] = host->data_buf[6];
		host->data_buf[4] = host->data_buf[8];
		host->data_buf[5] = host->data_buf[10];
	}
}

static uint16_t get_dev_status_v3(struct mxc_nand_host *host)
{
	writew(NFC_STATUS, NFC_V3_LAUNCH);
	wait_op_done(host, true);

	return readl(NFC_V3_CONFIG1) >> 16;
}

/* This function requests the NANDFC to perform a read of the
 * NAND device status and returns the current status. */
static uint16_t get_dev_status_v1_v2(struct mxc_nand_host *host)
{
	void __iomem *main_buf = host->main_area0;
	uint32_t store;
	uint16_t ret;

	writew(host->active_cs << 4, NFC_V1_V2_BUF_ADDR);

	/*
	 * The device status is stored in main_area0. To
	 * prevent corruption of the buffer save the value
	 * and restore it afterwards.
	 */
	store = readl(main_buf);

	writew(NFC_STATUS, NFC_V1_V2_CONFIG2);
	wait_op_done(host, true);

	ret = readw(main_buf);

	writel(store, main_buf);

	return ret;
}

/* This functions is used by upper layer to checks if device is ready */
static int mxc_nand_dev_ready(struct mtd_info *mtd)
{
	/*
	 * NFC handles R/B internally. Therefore, this function
	 * always returns status as ready.
	 */
	return 1;
}

static void mxc_nand_enable_hwecc(struct mtd_info *mtd, int mode)
{
	/*
	 * If HW ECC is enabled, we turn it on during init. There is
	 * no need to enable again here.
	 */
}

static int mxc_nand_correct_data_v1(struct mtd_info *mtd, u_char *dat,
				 u_char *read_ecc, u_char *calc_ecc)
{
	struct nand_chip *nand_chip = mtd->priv;
	struct mxc_nand_host *host = nand_chip->priv;

	/*
	 * 1-Bit errors are automatically corrected in HW.  No need for
	 * additional correction.  2-Bit errors cannot be corrected by
	 * HW ECC, so we need to return failure
	 */
	uint16_t ecc_status = readw(NFC_V1_V2_ECC_STATUS_RESULT);

	if (((ecc_status & 0x3) == 2) || ((ecc_status >> 2) == 2)) {
		pr_debug("MXC_NAND: HWECC uncorrectable 2-bit ECC error\n");
		return -1;
	}

	return 0;
}

static int mxc_nand_correct_data_v2_v3(struct mtd_info *mtd, u_char *dat,
				 u_char *read_ecc, u_char *calc_ecc)
{
	struct nand_chip *nand_chip = mtd->priv;
	struct mxc_nand_host *host = nand_chip->priv;
	u32 ecc_stat, err;
	int no_subpages = 1;
	int ret = 0;
	u8 ecc_bit_mask, err_limit;

	ecc_bit_mask = (host->eccsize == 4) ? 0x7 : 0xf;
	err_limit = (host->eccsize == 4) ? 0x4 : 0x8;

	no_subpages = mtd->writesize >> 9;

	if (nfc_is_v21())
		ecc_stat = readl(NFC_V1_V2_ECC_STATUS_RESULT);
	else
		ecc_stat = readl(NFC_V3_ECC_STATUS_RESULT);

	do {
		err = ecc_stat & ecc_bit_mask;
		if (err > err_limit) {
			printk(KERN_WARNING "UnCorrectable RS-ECC Error\n");
			return -1;
		} else {
			ret += err;
		}
		ecc_stat >>= 4;
	} while (--no_subpages);

	mtd->ecc_stats.corrected += ret;
	pr_debug("%d Symbol Correctable RS-ECC Error\n", ret);

	return ret;
}

static int mxc_nand_calculate_ecc(struct mtd_info *mtd, const u_char *dat,
				  u_char *ecc_code)
{
	return 0;
}

static u_char mxc_nand_read_byte(struct mtd_info *mtd)
{
	struct nand_chip *nand_chip = mtd->priv;
	struct mxc_nand_host *host = nand_chip->priv;
	uint8_t ret;

	/* Check for status request */
	if (host->status_request)
		return host->get_dev_status(host) & 0xFF;

	ret = *(uint8_t *)(host->data_buf + host->buf_start);
	host->buf_start++;

	return ret;
}

static uint16_t mxc_nand_read_word(struct mtd_info *mtd)
{
	struct nand_chip *nand_chip = mtd->priv;
	struct mxc_nand_host *host = nand_chip->priv;
	uint16_t ret;

	ret = *(uint16_t *)(host->data_buf + host->buf_start);
	host->buf_start += 2;

	return ret;
}

/* Write data of length len to buffer buf. The data to be
 * written on NAND Flash is first copied to RAMbuffer. After the Data Input
 * Operation by the NFC, the data is written to NAND Flash */
static void mxc_nand_write_buf(struct mtd_info *mtd,
				const u_char *buf, int len)
{
	struct nand_chip *nand_chip = mtd->priv;
	struct mxc_nand_host *host = nand_chip->priv;
	u16 col = host->buf_start;
	int n = mtd->oobsize + mtd->writesize - col;

	n = min(n, len);

	memcpy(host->data_buf + col, buf, n);

	host->buf_start += n;
}

/* Read the data buffer from the NAND Flash. To read the data from NAND
 * Flash first the data output cycle is initiated by the NFC, which copies
 * the data to RAMbuffer. This data of length len is then copied to buffer buf.
 */
static void mxc_nand_read_buf(struct mtd_info *mtd, u_char *buf, int len)
{
	struct nand_chip *nand_chip = mtd->priv;
	struct mxc_nand_host *host = nand_chip->priv;
	u16 col = host->buf_start;
	int n = mtd->oobsize + mtd->writesize - col;

	n = min(n, len);

	memcpy(buf, host->data_buf + col, n);

	host->buf_start += n;
}

/* Used by the upper layer to verify the data in NAND Flash
 * with the data in the buf. */
static int mxc_nand_verify_buf(struct mtd_info *mtd,
				const u_char *buf, int len)
{
	return -EFAULT;
}

/* This function is used by upper layer for select and
 * deselect of the NAND chip */
static void mxc_nand_select_chip(struct mtd_info *mtd, int chip)
{
	struct nand_chip *nand_chip = mtd->priv;
	struct mxc_nand_host *host = nand_chip->priv;

	if (chip == -1) {
		/* Disable the NFC clock */
		if (host->clk_act) {
			clk_disable(host->clk);
			host->clk_act = 0;
		}
		return;
	}

	if (!host->clk_act) {
		/* Enable the NFC clock */
		clk_enable(host->clk);
		host->clk_act = 1;
	}

	if (nfc_is_v21()) {
		host->active_cs = chip;
		writew(host->active_cs << 4, NFC_V1_V2_BUF_ADDR);
	}
}

/*
 * Function to transfer data to/from spare area.
 */
static void copy_spare(struct mtd_info *mtd, bool bfrom)
{
	struct nand_chip *this = mtd->priv;
	struct mxc_nand_host *host = this->priv;
	u16 i, j;
	u16 n = mtd->writesize >> 9;
	u8 *d = host->data_buf + mtd->writesize;
	u8 *s = host->spare0;
	u16 t = host->spare_len;

	j = (mtd->oobsize / n >> 1) << 1;

	if (bfrom) {
		for (i = 0; i < n - 1; i++)
			memcpy(d + i * j, s + i * t, j);

		/* the last section */
		memcpy(d + i * j, s + i * t, mtd->oobsize - i * j);
	} else {
		for (i = 0; i < n - 1; i++)
			memcpy(&s[i * t], &d[i * j], j);

		/* the last section */
		memcpy(&s[i * t], &d[i * j], mtd->oobsize - i * j);
	}
}

static void mxc_do_addr_cycle(struct mtd_info *mtd, int column, int page_addr)
{
	struct nand_chip *nand_chip = mtd->priv;
	struct mxc_nand_host *host = nand_chip->priv;

	/* Write out column address, if necessary */
	if (column != -1) {
		/*
		 * MXC NANDFC can only perform full page+spare or
		 * spare-only read/write.  When the upper layers
		 * perform a read/write buf operation, the saved column
		  * address is used to index into the full page.
		 */
		host->send_addr(host, 0, page_addr == -1);
		if (mtd->writesize > 512)
			/* another col addr cycle for 2k page */
			host->send_addr(host, 0, false);
	}

	/* Write out page address, if necessary */
	if (page_addr != -1) {
		/* paddr_0 - p_addr_7 */
		host->send_addr(host, (page_addr & 0xff), false);

		if (mtd->writesize > 512) {
			if (mtd->size >= 0x10000000) {
				/* paddr_8 - paddr_15 */
				host->send_addr(host, (page_addr >> 8) & 0xff, false);
				host->send_addr(host, (page_addr >> 16) & 0xff, true);
			} else
				/* paddr_8 - paddr_15 */
				host->send_addr(host, (page_addr >> 8) & 0xff, true);
		} else {
			/* One more address cycle for higher density devices */
			if (mtd->size >= 0x4000000) {
				/* paddr_8 - paddr_15 */
				host->send_addr(host, (page_addr >> 8) & 0xff, false);
				host->send_addr(host, (page_addr >> 16) & 0xff, true);
			} else
				/* paddr_8 - paddr_15 */
				host->send_addr(host, (page_addr >> 8) & 0xff, true);
		}
	}
}

/*
 * v2 and v3 type controllers can do 4bit or 8bit ecc depending
 * on how much oob the nand chip has. For 8bit ecc we need at least
 * 26 bytes of oob data per 512 byte block.
 */
static int get_eccsize(struct mtd_info *mtd)
{
	int oobbytes_per_512 = 0;

	oobbytes_per_512 = mtd->oobsize * 512 / mtd->writesize;

	if (oobbytes_per_512 < 26)
		return 4;
	else
		return 8;
}

static void preset_v1_v2(struct mtd_info *mtd)
{
	struct nand_chip *nand_chip = mtd->priv;
	struct mxc_nand_host *host = nand_chip->priv;
	uint16_t config1 = 0;

	if (nand_chip->ecc.mode == NAND_ECC_HW)
		config1 |= NFC_V1_V2_CONFIG1_ECC_EN;

	if (nfc_is_v21())
		config1 |= NFC_V2_CONFIG1_FP_INT;

	if (!cpu_is_mx21())
		config1 |= NFC_V1_V2_CONFIG1_INT_MSK;

	if (nfc_is_v21() && mtd->writesize) {
		uint16_t pages_per_block = mtd->erasesize / mtd->writesize;

		host->eccsize = get_eccsize(mtd);
		if (host->eccsize == 4)
			config1 |= NFC_V2_CONFIG1_ECC_MODE_4;

		config1 |= NFC_V2_CONFIG1_PPB(ffs(pages_per_block) - 6);
	} else {
		host->eccsize = 1;
	}

	writew(config1, NFC_V1_V2_CONFIG1);
	/* preset operation */

	/* Unlock the internal RAM Buffer */
	writew(0x2, NFC_V1_V2_CONFIG);

	/* Blocks to be unlocked */
	if (nfc_is_v21()) {
		writew(0x0, NFC_V21_UNLOCKSTART_BLKADDR0);
		writew(0x0, NFC_V21_UNLOCKSTART_BLKADDR1);
		writew(0x0, NFC_V21_UNLOCKSTART_BLKADDR2);
		writew(0x0, NFC_V21_UNLOCKSTART_BLKADDR3);
		writew(0xffff, NFC_V21_UNLOCKEND_BLKADDR0);
		writew(0xffff, NFC_V21_UNLOCKEND_BLKADDR1);
		writew(0xffff, NFC_V21_UNLOCKEND_BLKADDR2);
		writew(0xffff, NFC_V21_UNLOCKEND_BLKADDR3);
	} else if (nfc_is_v1()) {
		writew(0x0, NFC_V1_UNLOCKSTART_BLKADDR);
		writew(0xffff, NFC_V1_UNLOCKEND_BLKADDR);
	} else
		BUG();

	/* Unlock Block Command for given address range */
	writew(0x4, NFC_V1_V2_WRPROT);
}

static void preset_v3(struct mtd_info *mtd)
{
	struct nand_chip *chip = mtd->priv;
	struct mxc_nand_host *host = chip->priv;
	uint32_t config2, config3;
	int i, addr_phases;

	writel(NFC_V3_CONFIG1_RBA(0), NFC_V3_CONFIG1);
	writel(NFC_V3_IPC_CREQ, NFC_V3_IPC);

	/* Unlock the internal RAM Buffer */
	writel(NFC_V3_WRPROT_BLS_UNLOCK | NFC_V3_WRPROT_UNLOCK,
			NFC_V3_WRPROT);

	/* Blocks to be unlocked */
	for (i = 0; i < NAND_MAX_CHIPS; i++)
		writel(0x0 |	(0xffff << 16),
				NFC_V3_WRPROT_UNLOCK_BLK_ADD0 + (i << 2));

	writel(0, NFC_V3_IPC);

	config2 = NFC_V3_CONFIG2_ONE_CYCLE |
		NFC_V3_CONFIG2_2CMD_PHASES |
		NFC_V3_CONFIG2_SPAS(mtd->oobsize >> 1) |
		NFC_V3_CONFIG2_ST_CMD(0x70) |
		NFC_V3_CONFIG2_INT_MSK |
		NFC_V3_CONFIG2_NUM_ADDR_PHASE0;

	if (chip->ecc.mode == NAND_ECC_HW)
		config2 |= NFC_V3_CONFIG2_ECC_EN;

	addr_phases = fls(chip->pagemask) >> 3;

	if (mtd->writesize == 2048) {
		config2 |= NFC_V3_CONFIG2_PS_2048;
		config2 |= NFC_V3_CONFIG2_NUM_ADDR_PHASE1(addr_phases);
	} else if (mtd->writesize == 4096) {
		config2 |= NFC_V3_CONFIG2_PS_4096;
		config2 |= NFC_V3_CONFIG2_NUM_ADDR_PHASE1(addr_phases);
	} else {
		config2 |= NFC_V3_CONFIG2_PS_512;
		config2 |= NFC_V3_CONFIG2_NUM_ADDR_PHASE1(addr_phases - 1);
	}

	if (mtd->writesize) {
		config2 |= NFC_V3_CONFIG2_PPB(ffs(mtd->erasesize / mtd->writesize) - 6);
		host->eccsize = get_eccsize(mtd);
		if (host->eccsize == 8)
			config2 |= NFC_V3_CONFIG2_ECC_MODE_8;
	}

	writel(config2, NFC_V3_CONFIG2);

	config3 = NFC_V3_CONFIG3_NUM_OF_DEVICES(0) |
			NFC_V3_CONFIG3_NO_SDMA |
			NFC_V3_CONFIG3_RBB_MODE |
			NFC_V3_CONFIG3_SBB(6) | /* Reset default */
			NFC_V3_CONFIG3_ADD_OP(0);

	if (!(chip->options & NAND_BUSWIDTH_16))
		config3 |= NFC_V3_CONFIG3_FW8;

	writel(config3, NFC_V3_CONFIG3);

	writel(0, NFC_V3_DELAY_LINE);
}

/* Used by the upper layer to write command to NAND Flash for
 * different operations to be carried out on NAND Flash */
static void mxc_nand_command(struct mtd_info *mtd, unsigned command,
				int column, int page_addr)
{
	struct nand_chip *nand_chip = mtd->priv;
	struct mxc_nand_host *host = nand_chip->priv;

	pr_debug("mxc_nand_command (cmd = 0x%x, col = 0x%x, page = 0x%x)\n",
	      command, column, page_addr);

	/* Reset command state information */
	host->status_request = false;

	/* Command pre-processing step */
	switch (command) {
	case NAND_CMD_RESET:
		host->preset(mtd);
		host->send_cmd(host, command, false);
		break;

	case NAND_CMD_STATUS:
		host->buf_start = 0;
		host->status_request = true;

		host->send_cmd(host, command, true);
		mxc_do_addr_cycle(mtd, column, page_addr);
		break;

	case NAND_CMD_READ0:
	case NAND_CMD_READOOB:
		if (command == NAND_CMD_READ0)
			host->buf_start = column;
		else
			host->buf_start = column + mtd->writesize;

		command = NAND_CMD_READ0; /* only READ0 is valid */

		host->send_cmd(host, command, false);
		mxc_do_addr_cycle(mtd, column, page_addr);

		if (mtd->writesize > 512)
			host->send_cmd(host, NAND_CMD_READSTART, true);

		host->send_page(mtd, NFC_OUTPUT);

		memcpy(host->data_buf, host->main_area0, mtd->writesize);
		copy_spare(mtd, true);
		break;

	case NAND_CMD_SEQIN:
		if (column >= mtd->writesize)
			/* call ourself to read a page */
			mxc_nand_command(mtd, NAND_CMD_READ0, 0, page_addr);

		host->buf_start = column;

		host->send_cmd(host, command, false);
		mxc_do_addr_cycle(mtd, column, page_addr);
		break;

	case NAND_CMD_PAGEPROG:
		memcpy(host->main_area0, host->data_buf, mtd->writesize);
		copy_spare(mtd, false);
		host->send_page(mtd, NFC_INPUT);
		host->send_cmd(host, command, true);
		mxc_do_addr_cycle(mtd, column, page_addr);
		break;

	case NAND_CMD_READID:
		host->send_cmd(host, command, true);
		mxc_do_addr_cycle(mtd, column, page_addr);
		host->send_read_id(host);
		host->buf_start = column;
		break;

	case NAND_CMD_ERASE1:
	case NAND_CMD_ERASE2:
		host->send_cmd(host, command, false);
		mxc_do_addr_cycle(mtd, column, page_addr);

		break;
	}
}

/*
 * The generic flash bbt decriptors overlap with our ecc
 * hardware, so define some i.MX specific ones.
 */
static uint8_t bbt_pattern[] = { 'B', 'b', 't', '0' };
static uint8_t mirror_pattern[] = { '1', 't', 'b', 'B' };

static struct nand_bbt_descr bbt_main_descr = {
	.options = NAND_BBT_LASTBLOCK | NAND_BBT_CREATE | NAND_BBT_WRITE
	    | NAND_BBT_2BIT | NAND_BBT_VERSION | NAND_BBT_PERCHIP,
	.offs = 0,
	.len = 4,
	.veroffs = 4,
	.maxblocks = 4,
	.pattern = bbt_pattern,
};

static struct nand_bbt_descr bbt_mirror_descr = {
	.options = NAND_BBT_LASTBLOCK | NAND_BBT_CREATE | NAND_BBT_WRITE
	    | NAND_BBT_2BIT | NAND_BBT_VERSION | NAND_BBT_PERCHIP,
	.offs = 0,
	.len = 4,
	.veroffs = 4,
	.maxblocks = 4,
	.pattern = mirror_pattern,
};

static int __init mxcnd_probe(struct platform_device *pdev)
{
	struct nand_chip *this;
	struct mtd_info *mtd;
	struct mxc_nand_platform_data *pdata = pdev->dev.platform_data;
	struct mxc_nand_host *host;
	struct resource *res;
	int err = 0;
	struct nand_ecclayout *oob_smallpage, *oob_largepage;

	/* Allocate memory for MTD device structure and private data */
	host = kzalloc(sizeof(struct mxc_nand_host) + NAND_MAX_PAGESIZE +
			NAND_MAX_OOBSIZE, GFP_KERNEL);
	if (!host)
		return -ENOMEM;

	host->data_buf = (uint8_t *)(host + 1);

	host->dev = &pdev->dev;
	/* structures must be linked */
	this = &host->nand;
	mtd = &host->mtd;
	mtd->priv = this;
	mtd->owner = THIS_MODULE;
	mtd->dev.parent = &pdev->dev;
	mtd->name = DRIVER_NAME;

	/* 50 us command delay time */
	this->chip_delay = 5;

	this->priv = host;
	this->dev_ready = mxc_nand_dev_ready;
	this->cmdfunc = mxc_nand_command;
	this->select_chip = mxc_nand_select_chip;
	this->read_byte = mxc_nand_read_byte;
	this->read_word = mxc_nand_read_word;
	this->write_buf = mxc_nand_write_buf;
	this->read_buf = mxc_nand_read_buf;
	this->verify_buf = mxc_nand_verify_buf;

	host->clk = clk_get(&pdev->dev, "nfc");
	if (IS_ERR(host->clk)) {
		err = PTR_ERR(host->clk);
		goto eclk;
	}

	clk_enable(host->clk);
	host->clk_act = 1;

	res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
	if (!res) {
		err = -ENODEV;
		goto eres;
	}

	host->base = ioremap(res->start, resource_size(res));
	if (!host->base) {
		err = -ENOMEM;
		goto eres;
	}

	host->main_area0 = host->base;

	if (nfc_is_v1() || nfc_is_v21()) {
		host->preset = preset_v1_v2;
		host->send_cmd = send_cmd_v1_v2;
		host->send_addr = send_addr_v1_v2;
		host->send_page = send_page_v1_v2;
		host->send_read_id = send_read_id_v1_v2;
		host->get_dev_status = get_dev_status_v1_v2;
		host->check_int = check_int_v1_v2;
		if (cpu_is_mx21())
			host->irq_control = irq_control_mx21;
		else
			host->irq_control = irq_control_v1_v2;
	}

	if (nfc_is_v21()) {
		host->regs = host->base + 0x1e00;
		host->spare0 = host->base + 0x1000;
		host->spare_len = 64;
		oob_smallpage = &nandv2_hw_eccoob_smallpage;
		oob_largepage = &nandv2_hw_eccoob_largepage;
		this->ecc.bytes = 9;
	} else if (nfc_is_v1()) {
		host->regs = host->base + 0xe00;
		host->spare0 = host->base + 0x800;
		host->spare_len = 16;
		oob_smallpage = &nandv1_hw_eccoob_smallpage;
		oob_largepage = &nandv1_hw_eccoob_largepage;
		this->ecc.bytes = 3;
		host->eccsize = 1;
	} else if (nfc_is_v3_2()) {
		res = platform_get_resource(pdev, IORESOURCE_MEM, 1);
		if (!res) {
			err = -ENODEV;
			goto eirq;
		}
		host->regs_ip = ioremap(res->start, resource_size(res));
		if (!host->regs_ip) {
			err = -ENOMEM;
			goto eirq;
		}
		host->regs_axi = host->base + 0x1e00;
		host->spare0 = host->base + 0x1000;
		host->spare_len = 64;
		host->preset = preset_v3;
		host->send_cmd = send_cmd_v3;
		host->send_addr = send_addr_v3;
		host->send_page = send_page_v3;
		host->send_read_id = send_read_id_v3;
		host->check_int = check_int_v3;
		host->get_dev_status = get_dev_status_v3;
		host->irq_control = irq_control_v3;
		oob_smallpage = &nandv2_hw_eccoob_smallpage;
		oob_largepage = &nandv2_hw_eccoob_largepage;
	} else
		BUG();

	this->ecc.size = 512;
	this->ecc.layout = oob_smallpage;

	if (pdata->hw_ecc) {
		this->ecc.calculate = mxc_nand_calculate_ecc;
		this->ecc.hwctl = mxc_nand_enable_hwecc;
		if (nfc_is_v1())
			this->ecc.correct = mxc_nand_correct_data_v1;
		else
			this->ecc.correct = mxc_nand_correct_data_v2_v3;
		this->ecc.mode = NAND_ECC_HW;
	} else {
		this->ecc.mode = NAND_ECC_SOFT;
	}

	/* NAND bus width determines access funtions used by upper layer */
	if (pdata->width == 2)
		this->options |= NAND_BUSWIDTH_16;

	if (pdata->flash_bbt) {
		this->bbt_td = &bbt_main_descr;
		this->bbt_md = &bbt_mirror_descr;
		/* update flash based bbt */
		this->bbt_options |= NAND_BBT_USE_FLASH;
	}

	init_completion(&host->op_completion);

	host->irq = platform_get_irq(pdev, 0);

	/*
	 * mask the interrupt. For i.MX21 explicitely call
	 * irq_control_v1_v2 to use the mask bit. We can't call
	 * disable_irq_nosync() for an interrupt we do not own yet.
	 */
	if (cpu_is_mx21())
		irq_control_v1_v2(host, 0);
	else
		host->irq_control(host, 0);

	err = request_irq(host->irq, mxc_nfc_irq, IRQF_DISABLED, DRIVER_NAME, host);
	if (err)
		goto eirq;

	host->irq_control(host, 0);

	/*
	 * Now that the interrupt is disabled make sure the interrupt
	 * mask bit is cleared on i.MX21. Otherwise we can't read
	 * the interrupt status bit on this machine.
	 */
	if (cpu_is_mx21())
		irq_control_v1_v2(host, 1);

	/* first scan to find the device and get the page size */
	if (nand_scan_ident(mtd, nfc_is_v21() ? 4 : 1, NULL)) {
		err = -ENXIO;
		goto escan;
	}

	/* Call preset again, with correct writesize this time */
	host->preset(mtd);

	if (mtd->writesize == 2048)
		this->ecc.layout = oob_largepage;
	if (nfc_is_v21() && mtd->writesize == 4096)
		this->ecc.layout = &nandv2_hw_eccoob_4k;

	/* second phase scan */
	if (nand_scan_tail(mtd)) {
		err = -ENXIO;
		goto escan;
	}

	/* Register the partitions */
	mtd_device_parse_register(mtd, part_probes, NULL, pdata->parts,
				  pdata->nr_parts);

	platform_set_drvdata(pdev, host);

	return 0;

escan:
	free_irq(host->irq, host);
eirq:
	if (host->regs_ip)
		iounmap(host->regs_ip);
	iounmap(host->base);
eres:
	clk_put(host->clk);
eclk:
	kfree(host);

	return err;
}

static int __devexit mxcnd_remove(struct platform_device *pdev)
{
	struct mxc_nand_host *host = platform_get_drvdata(pdev);

	clk_put(host->clk);

	platform_set_drvdata(pdev, NULL);

	nand_release(&host->mtd);
	free_irq(host->irq, host);
	if (host->regs_ip)
		iounmap(host->regs_ip);
	iounmap(host->base);
	kfree(host);

	return 0;
}

static struct platform_driver mxcnd_driver = {
	.driver = {
		   .name = DRIVER_NAME,
	},
	.remove = __devexit_p(mxcnd_remove),
};

static int __init mxc_nd_init(void)
{
	return platform_driver_probe(&mxcnd_driver, mxcnd_probe);
}

static void __exit mxc_nd_cleanup(void)
{
	/* Unregister the device structure */
	platform_driver_unregister(&mxcnd_driver);
}

module_init(mxc_nd_init);
module_exit(mxc_nd_cleanup);

MODULE_AUTHOR("Freescale Semiconductor, Inc.");
MODULE_DESCRIPTION("MXC NAND MTD driver");
MODULE_LICENSE("GPL");