summaryrefslogtreecommitdiffstats
path: root/include/linux/mtd/nand.h
blob: 6fc3e07497e0175aa49f6ffe856c9131bbc30f7b (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
/*
 *  linux/include/linux/mtd/nand.h
 *
 *  Copyright (c) 2000 David Woodhouse <dwmw2@mvhi.com>
 *                     Steven J. Hill <sjhill@realitydiluted.com>
 *		       Thomas Gleixner <tglx@linutronix.de>
 *
 * $Id: nand.h,v 1.74 2005/09/15 13:58:50 vwool Exp $
 *
 * 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.
 *
 * Info:
 *	Contains standard defines and IDs for NAND flash devices
 *
 * Changelog:
 *	See git changelog.
 */
#ifndef __LINUX_MTD_NAND_H
#define __LINUX_MTD_NAND_H

#include <linux/wait.h>
#include <linux/spinlock.h>
#include <linux/mtd/mtd.h>

struct mtd_info;
/* Scan and identify a NAND device */
extern int nand_scan (struct mtd_info *mtd, int max_chips);
/* Separate phases of nand_scan(), allowing board driver to intervene
 * and override command or ECC setup according to flash type */
extern int nand_scan_ident(struct mtd_info *mtd, int max_chips);
extern int nand_scan_tail(struct mtd_info *mtd);

/* Free resources held by the NAND device */
extern void nand_release (struct mtd_info *mtd);

/* Internal helper for board drivers which need to override command function */
extern void nand_wait_ready(struct mtd_info *mtd);

/* The maximum number of NAND chips in an array */
#define NAND_MAX_CHIPS		8

/* This constant declares the max. oobsize / page, which
 * is supported now. If you add a chip with bigger oobsize/page
 * adjust this accordingly.
 */
#define NAND_MAX_OOBSIZE	64
#define NAND_MAX_PAGESIZE	2048

/*
 * Constants for hardware specific CLE/ALE/NCE function
 *
 * These are bits which can be or'ed to set/clear multiple
 * bits in one go.
 */
/* Select the chip by setting nCE to low */
#define NAND_NCE		0x01
/* Select the command latch by setting CLE to high */
#define NAND_CLE		0x02
/* Select the address latch by setting ALE to high */
#define NAND_ALE		0x04

#define NAND_CTRL_CLE		(NAND_NCE | NAND_CLE)
#define NAND_CTRL_ALE		(NAND_NCE | NAND_ALE)
#define NAND_CTRL_CHANGE	0x80

/*
 * Standard NAND flash commands
 */
#define NAND_CMD_READ0		0
#define NAND_CMD_READ1		1
#define NAND_CMD_RNDOUT		5
#define NAND_CMD_PAGEPROG	0x10
#define NAND_CMD_READOOB	0x50
#define NAND_CMD_ERASE1		0x60
#define NAND_CMD_STATUS		0x70
#define NAND_CMD_STATUS_MULTI	0x71
#define NAND_CMD_SEQIN		0x80
#define NAND_CMD_RNDIN		0x85
#define NAND_CMD_READID		0x90
#define NAND_CMD_ERASE2		0xd0
#define NAND_CMD_RESET		0xff

/* Extended commands for large page devices */
#define NAND_CMD_READSTART	0x30
#define NAND_CMD_RNDOUTSTART	0xE0
#define NAND_CMD_CACHEDPROG	0x15

/* Extended commands for AG-AND device */
/*
 * Note: the command for NAND_CMD_DEPLETE1 is really 0x00 but
 *       there is no way to distinguish that from NAND_CMD_READ0
 *       until the remaining sequence of commands has been completed
 *       so add a high order bit and mask it off in the command.
 */
#define NAND_CMD_DEPLETE1	0x100
#define NAND_CMD_DEPLETE2	0x38
#define NAND_CMD_STATUS_MULTI	0x71
#define NAND_CMD_STATUS_ERROR	0x72
/* multi-bank error status (banks 0-3) */
#define NAND_CMD_STATUS_ERROR0	0x73
#define NAND_CMD_STATUS_ERROR1	0x74
#define NAND_CMD_STATUS_ERROR2	0x75
#define NAND_CMD_STATUS_ERROR3	0x76
#define NAND_CMD_STATUS_RESET	0x7f
#define NAND_CMD_STATUS_CLEAR	0xff

#define NAND_CMD_NONE		-1

/* Status bits */
#define NAND_STATUS_FAIL	0x01
#define NAND_STATUS_FAIL_N1	0x02
#define NAND_STATUS_TRUE_READY	0x20
#define NAND_STATUS_READY	0x40
#define NAND_STATUS_WP		0x80

/*
 * Constants for ECC_MODES
 */
typedef enum {
	NAND_ECC_NONE,
	NAND_ECC_SOFT,
	NAND_ECC_HW,
	NAND_ECC_HW_SYNDROME,
} nand_ecc_modes_t;

/*
 * Constants for Hardware ECC
 */
/* Reset Hardware ECC for read */
#define NAND_ECC_READ		0
/* Reset Hardware ECC for write */
#define NAND_ECC_WRITE		1
/* Enable Hardware ECC before syndrom is read back from flash */
#define NAND_ECC_READSYN	2

/* Bit mask for flags passed to do_nand_read_ecc */
#define NAND_GET_DEVICE		0x80


/* Option constants for bizarre disfunctionality and real
*  features
*/
/* Chip can not auto increment pages */
#define NAND_NO_AUTOINCR	0x00000001
/* Buswitdh is 16 bit */
#define NAND_BUSWIDTH_16	0x00000002
/* Device supports partial programming without padding */
#define NAND_NO_PADDING		0x00000004
/* Chip has cache program function */
#define NAND_CACHEPRG		0x00000008
/* Chip has copy back function */
#define NAND_COPYBACK		0x00000010
/* AND Chip which has 4 banks and a confusing page / block
 * assignment. See Renesas datasheet for further information */
#define NAND_IS_AND		0x00000020
/* Chip has a array of 4 pages which can be read without
 * additional ready /busy waits */
#define NAND_4PAGE_ARRAY	0x00000040
/* Chip requires that BBT is periodically rewritten to prevent
 * bits from adjacent blocks from 'leaking' in altering data.
 * This happens with the Renesas AG-AND chips, possibly others.  */
#define BBT_AUTO_REFRESH	0x00000080
/* Chip does not require ready check on read. True
 * for all large page devices, as they do not support
 * autoincrement.*/
#define NAND_NO_READRDY		0x00000100

/* Options valid for Samsung large page devices */
#define NAND_SAMSUNG_LP_OPTIONS \
	(NAND_NO_PADDING | NAND_CACHEPRG | NAND_COPYBACK)

/* Macros to identify the above */
#define NAND_CANAUTOINCR(chip) (!(chip->options & NAND_NO_AUTOINCR))
#define NAND_MUST_PAD(chip) (!(chip->options & NAND_NO_PADDING))
#define NAND_HAS_CACHEPROG(chip) ((chip->options & NAND_CACHEPRG))
#define NAND_HAS_COPYBACK(chip) ((chip->options & NAND_COPYBACK))

/* Mask to zero out the chip options, which come from the id table */
#define NAND_CHIPOPTIONS_MSK	(0x0000ffff & ~NAND_NO_AUTOINCR)

/* Non chip related options */
/* Use a flash based bad block table. This option is passed to the
 * default bad block table function. */
#define NAND_USE_FLASH_BBT	0x00010000
/* This option skips the bbt scan during initialization. */
#define NAND_SKIP_BBTSCAN	0x00020000
/* This option is defined if the board driver allocates its own buffers
   (e.g. because it needs them DMA-coherent */
#define NAND_OWN_BUFFERS	0x00040000
/* Options set by nand scan */
/* Nand scan has allocated controller struct */
#define NAND_CONTROLLER_ALLOC	0x80000000


/*
 * nand_state_t - chip states
 * Enumeration for NAND flash chip state
 */
typedef enum {
	FL_READY,
	FL_READING,
	FL_WRITING,
	FL_ERASING,
	FL_SYNCING,
	FL_CACHEDPRG,
	FL_PM_SUSPENDED,
} nand_state_t;

/* Keep gcc happy */
struct nand_chip;

/**
 * struct nand_hw_control - Control structure for hardware controller (e.g ECC generator) shared among independent devices
 * @lock:               protection lock
 * @active:		the mtd device which holds the controller currently
 * @wq:			wait queue to sleep on if a NAND operation is in progress
 *                      used instead of the per chip wait queue when a hw controller is available
 */
struct nand_hw_control {
	spinlock_t	 lock;
	struct nand_chip *active;
	wait_queue_head_t wq;
};

/**
 * struct nand_ecc_ctrl - Control structure for ecc
 * @mode:	ecc mode
 * @steps:	number of ecc steps per page
 * @size:	data bytes per ecc step
 * @bytes:	ecc bytes per step
 * @total:	total number of ecc bytes per page
 * @prepad:	padding information for syndrome based ecc generators
 * @postpad:	padding information for syndrome based ecc generators
 * @layout:	ECC layout control struct pointer
 * @hwctl:	function to control hardware ecc generator. Must only
 *		be provided if an hardware ECC is available
 * @calculate:	function for ecc calculation or readback from ecc hardware
 * @correct:	function for ecc correction, matching to ecc generator (sw/hw)
 * @read_page_raw:	function to read a raw page without ECC
 * @write_page_raw:	function to write a raw page without ECC
 * @read_page:	function to read a page according to the ecc generator requirements
 * @write_page:	function to write a page according to the ecc generator requirements
 * @read_oob:	function to read chip OOB data
 * @write_oob:	function to write chip OOB data
 */
struct nand_ecc_ctrl {
	nand_ecc_modes_t	mode;
	int			steps;
	int			size;
	int			bytes;
	int			total;
	int			prepad;
	int			postpad;
	struct nand_ecclayout	*layout;
	void			(*hwctl)(struct mtd_info *mtd, int mode);
	int			(*calculate)(struct mtd_info *mtd,
					     const uint8_t *dat,
					     uint8_t *ecc_code);
	int			(*correct)(struct mtd_info *mtd, uint8_t *dat,
					   uint8_t *read_ecc,
					   uint8_t *calc_ecc);
	int			(*read_page_raw)(struct mtd_info *mtd,
						 struct nand_chip *chip,
						 uint8_t *buf);
	void			(*write_page_raw)(struct mtd_info *mtd,
						  struct nand_chip *chip,
						  const uint8_t *buf);
	int			(*read_page)(struct mtd_info *mtd,
					     struct nand_chip *chip,
					     uint8_t *buf);
	void			(*write_page)(struct mtd_info *mtd,
					      struct nand_chip *chip,
					      const uint8_t *buf);
	int			(*read_oob)(struct mtd_info *mtd,
					    struct nand_chip *chip,
					    int page,
					    int sndcmd);
	int			(*write_oob)(struct mtd_info *mtd,
					     struct nand_chip *chip,
					     int page);
};

/**
 * struct nand_buffers - buffer structure for read/write
 * @ecccalc:	buffer for calculated ecc
 * @ecccode:	buffer for ecc read from flash
 * @databuf:	buffer for data - dynamically sized
 *
 * Do not change the order of buffers. databuf and oobrbuf must be in
 * consecutive order.
 */
struct nand_buffers {
	uint8_t	ecccalc[NAND_MAX_OOBSIZE];
	uint8_t	ecccode[NAND_MAX_OOBSIZE];
	uint8_t databuf[NAND_MAX_PAGESIZE + NAND_MAX_OOBSIZE];
};

/**
 * struct nand_chip - NAND Private Flash Chip Data
 * @IO_ADDR_R:		[BOARDSPECIFIC] address to read the 8 I/O lines of the flash device
 * @IO_ADDR_W:		[BOARDSPECIFIC] address to write the 8 I/O lines of the flash device
 * @read_byte:		[REPLACEABLE] read one byte from the chip
 * @read_word:		[REPLACEABLE] read one word from the chip
 * @write_buf:		[REPLACEABLE] write data from the buffer to the chip
 * @read_buf:		[REPLACEABLE] read data from the chip into the buffer
 * @verify_buf:		[REPLACEABLE] verify buffer contents against the chip data
 * @select_chip:	[REPLACEABLE] select chip nr
 * @block_bad:		[REPLACEABLE] check, if the block is bad
 * @block_markbad:	[REPLACEABLE] mark the block bad
 * @cmd_ctrl:		[BOARDSPECIFIC] hardwarespecific funtion for controlling
 *			ALE/CLE/nCE. Also used to write command and address
 * @dev_ready:		[BOARDSPECIFIC] hardwarespecific function for accesing device ready/busy line
 *			If set to NULL no access to ready/busy is available and the ready/busy information
 *			is read from the chip status register
 * @cmdfunc:		[REPLACEABLE] hardwarespecific function for writing commands to the chip
 * @waitfunc:		[REPLACEABLE] hardwarespecific function for wait on ready
 * @ecc:		[BOARDSPECIFIC] ecc control ctructure
 * @buffers:		buffer structure for read/write
 * @hwcontrol:		platform-specific hardware control structure
 * @ops:		oob operation operands
 * @erase_cmd:		[INTERN] erase command write function, selectable due to AND support
 * @scan_bbt:		[REPLACEABLE] function to scan bad block table
 * @chip_delay:		[BOARDSPECIFIC] chip dependent delay for transfering data from array to read regs (tR)
 * @wq:			[INTERN] wait queue to sleep on if a NAND operation is in progress
 * @state:		[INTERN] the current state of the NAND device
 * @oob_poi:		poison value buffer
 * @page_shift:		[INTERN] number of address bits in a page (column address bits)
 * @phys_erase_shift:	[INTERN] number of address bits in a physical eraseblock
 * @bbt_erase_shift:	[INTERN] number of address bits in a bbt entry
 * @chip_shift:		[INTERN] number of address bits in one chip
 * @datbuf:		[INTERN] internal buffer for one page + oob
 * @oobbuf:		[INTERN] oob buffer for one eraseblock
 * @oobdirty:		[INTERN] indicates that oob_buf must be reinitialized
 * @data_poi:		[INTERN] pointer to a data buffer
 * @options:		[BOARDSPECIFIC] various chip options. They can partly be set to inform nand_scan about
 *			special functionality. See the defines for further explanation
 * @badblockpos:	[INTERN] position of the bad block marker in the oob area
 * @numchips:		[INTERN] number of physical chips
 * @chipsize:		[INTERN] the size of one chip for multichip arrays
 * @pagemask:		[INTERN] page number mask = number of (pages / chip) - 1
 * @pagebuf:		[INTERN] holds the pagenumber which is currently in data_buf
 * @ecclayout:		[REPLACEABLE] the default ecc placement scheme
 * @bbt:		[INTERN] bad block table pointer
 * @bbt_td:		[REPLACEABLE] bad block table descriptor for flash lookup
 * @bbt_md:		[REPLACEABLE] bad block table mirror descriptor
 * @badblock_pattern:	[REPLACEABLE] bad block scan pattern used for initial bad block scan
 * @controller:		[REPLACEABLE] a pointer to a hardware controller structure
 *			which is shared among multiple independend devices
 * @priv:		[OPTIONAL] pointer to private chip date
 * @errstat:		[OPTIONAL] hardware specific function to perform additional error status checks
 *			(determine if errors are correctable)
 * @write_page		[REPLACEABLE] High-level page write function
 */

struct nand_chip {
	void  __iomem	*IO_ADDR_R;
	void  __iomem	*IO_ADDR_W;

	uint8_t		(*read_byte)(struct mtd_info *mtd);
	u16		(*read_word)(struct mtd_info *mtd);
	void		(*write_buf)(struct mtd_info *mtd, const uint8_t *buf, int len);
	void		(*read_buf)(struct mtd_info *mtd, uint8_t *buf, int len);
	int		(*verify_buf)(struct mtd_info *mtd, const uint8_t *buf, int len);
	void		(*select_chip)(struct mtd_info *mtd, int chip);
	int		(*block_bad)(struct mtd_info *mtd, loff_t ofs, int getchip);
	int		(*block_markbad)(struct mtd_info *mtd, loff_t ofs);
	void		(*cmd_ctrl)(struct mtd_info *mtd, int dat,
				    unsigned int ctrl);
	int		(*dev_ready)(struct mtd_info *mtd);
	void		(*cmdfunc)(struct mtd_info *mtd, unsigned command, int column, int page_addr);
	int		(*waitfunc)(struct mtd_info *mtd, struct nand_chip *this);
	void		(*erase_cmd)(struct mtd_info *mtd, int page);
	int		(*scan_bbt)(struct mtd_info *mtd);
	int		(*errstat)(struct mtd_info *mtd, struct nand_chip *this, int state, int status, int page);
	int		(*write_page)(struct mtd_info *mtd, struct nand_chip *chip,
				      const uint8_t *buf, int page, int cached, int raw);

	int		chip_delay;
	unsigned int	options;

	int		page_shift;
	int		phys_erase_shift;
	int		bbt_erase_shift;
	int		chip_shift;
	int		numchips;
	unsigned long	chipsize;
	int		pagemask;
	int		pagebuf;
	int		badblockpos;

	nand_state_t	state;

	uint8_t		*oob_poi;
	struct nand_hw_control  *controller;
	struct nand_ecclayout	*ecclayout;

	struct nand_ecc_ctrl ecc;
	struct nand_buffers *buffers;
	struct nand_hw_control hwcontrol;

	struct mtd_oob_ops ops;

	uint8_t		*bbt;
	struct nand_bbt_descr	*bbt_td;
	struct nand_bbt_descr	*bbt_md;

	struct nand_bbt_descr	*badblock_pattern;

	void		*priv;
};

/*
 * NAND Flash Manufacturer ID Codes
 */
#define NAND_MFR_TOSHIBA	0x98
#define NAND_MFR_SAMSUNG	0xec
#define NAND_MFR_FUJITSU	0x04
#define NAND_MFR_NATIONAL	0x8f
#define NAND_MFR_RENESAS	0x07
#define NAND_MFR_STMICRO	0x20
#define NAND_MFR_HYNIX		0xad

/**
 * struct nand_flash_dev - NAND Flash Device ID Structure
 * @name:	Identify the device type
 * @id:		device ID code
 * @pagesize:	Pagesize in bytes. Either 256 or 512 or 0
 *		If the pagesize is 0, then the real pagesize
 *		and the eraseize are determined from the
 *		extended id bytes in the chip
 * @erasesize:	Size of an erase block in the flash device.
 * @chipsize:	Total chipsize in Mega Bytes
 * @options:	Bitfield to store chip relevant options
 */
struct nand_flash_dev {
	char *name;
	int id;
	unsigned long pagesize;
	unsigned long chipsize;
	unsigned long erasesize;
	unsigned long options;
};

/**
 * struct nand_manufacturers - NAND Flash Manufacturer ID Structure
 * @name:	Manufacturer name
 * @id:		manufacturer ID code of device.
*/
struct nand_manufacturers {
	int id;
	char * name;
};

extern struct nand_flash_dev nand_flash_ids[];
extern struct nand_manufacturers nand_manuf_ids[];

/**
 * struct nand_bbt_descr - bad block table descriptor
 * @options:	options for this descriptor
 * @pages:	the page(s) where we find the bbt, used with option BBT_ABSPAGE
 *		when bbt is searched, then we store the found bbts pages here.
 *		Its an array and supports up to 8 chips now
 * @offs:	offset of the pattern in the oob area of the page
 * @veroffs:	offset of the bbt version counter in the oob are of the page
 * @version:	version read from the bbt page during scan
 * @len:	length of the pattern, if 0 no pattern check is performed
 * @maxblocks:	maximum number of blocks to search for a bbt. This number of
 *		blocks is reserved at the end of the device where the tables are
 *		written.
 * @reserved_block_code: if non-0, this pattern denotes a reserved (rather than
 *              bad) block in the stored bbt
 * @pattern:	pattern to identify bad block table or factory marked good /
 *		bad blocks, can be NULL, if len = 0
 *
 * Descriptor for the bad block table marker and the descriptor for the
 * pattern which identifies good and bad blocks. The assumption is made
 * that the pattern and the version count are always located in the oob area
 * of the first block.
 */
struct nand_bbt_descr {
	int	options;
	int	pages[NAND_MAX_CHIPS];
	int	offs;
	int	veroffs;
	uint8_t	version[NAND_MAX_CHIPS];
	int	len;
	int	maxblocks;
	int	reserved_block_code;
	uint8_t	*pattern;
};

/* Options for the bad block table descriptors */

/* The number of bits used per block in the bbt on the device */
#define NAND_BBT_NRBITS_MSK	0x0000000F
#define NAND_BBT_1BIT		0x00000001
#define NAND_BBT_2BIT		0x00000002
#define NAND_BBT_4BIT		0x00000004
#define NAND_BBT_8BIT		0x00000008
/* The bad block table is in the last good block of the device */
#define	NAND_BBT_LASTBLOCK	0x00000010
/* The bbt is at the given page, else we must scan for the bbt */
#define NAND_BBT_ABSPAGE	0x00000020
/* The bbt is at the given page, else we must scan for the bbt */
#define NAND_BBT_SEARCH		0x00000040
/* bbt is stored per chip on multichip devices */
#define NAND_BBT_PERCHIP	0x00000080
/* bbt has a version counter at offset veroffs */
#define NAND_BBT_VERSION	0x00000100
/* Create a bbt if none axists */
#define NAND_BBT_CREATE		0x00000200
/* Search good / bad pattern through all pages of a block */
#define NAND_BBT_SCANALLPAGES	0x00000400
/* Scan block empty during good / bad block scan */
#define NAND_BBT_SCANEMPTY	0x00000800
/* Write bbt if neccecary */
#define NAND_BBT_WRITE		0x00001000
/* Read and write back block contents when writing bbt */
#define NAND_BBT_SAVECONTENT	0x00002000
/* Search good / bad pattern on the first and the second page */
#define NAND_BBT_SCAN2NDPAGE	0x00004000

/* The maximum number of blocks to scan for a bbt */
#define NAND_BBT_SCAN_MAXBLOCKS	4

extern int nand_scan_bbt(struct mtd_info *mtd, struct nand_bbt_descr *bd);
extern int nand_update_bbt(struct mtd_info *mtd, loff_t offs);
extern int nand_default_bbt(struct mtd_info *mtd);
extern int nand_isbad_bbt(struct mtd_info *mtd, loff_t offs, int allowbbt);
extern int nand_erase_nand(struct mtd_info *mtd, struct erase_info *instr,
			   int allowbbt);
extern int nand_do_read(struct mtd_info *mtd, loff_t from, size_t len,
			size_t * retlen, uint8_t * buf);

/*
* Constants for oob configuration
*/
#define NAND_SMALL_BADBLOCK_POS		5
#define NAND_LARGE_BADBLOCK_POS		0

/**
 * struct platform_nand_chip - chip level device structure
 * @nr_chips:		max. number of chips to scan for
 * @chip_offset:	chip number offset
 * @nr_partitions:	number of partitions pointed to by partitions (or zero)
 * @partitions:		mtd partition list
 * @chip_delay:		R/B delay value in us
 * @options:		Option flags, e.g. 16bit buswidth
 * @ecclayout:		ecc layout info structure
 * @priv:		hardware controller specific settings
 */
struct platform_nand_chip {
	int			nr_chips;
	int			chip_offset;
	int			nr_partitions;
	struct mtd_partition	*partitions;
	struct nand_ecclayout	*ecclayout;
	int			chip_delay;
	unsigned int		options;
	void			*priv;
};

/**
 * struct platform_nand_ctrl - controller level device structure
 * @hwcontrol:		platform specific hardware control structure
 * @dev_ready:		platform specific function to read ready/busy pin
 * @select_chip:	platform specific chip select function
 * @priv:		private data to transport driver specific settings
 *
 * All fields are optional and depend on the hardware driver requirements
 */
struct platform_nand_ctrl {
	void		(*hwcontrol)(struct mtd_info *mtd, int cmd);
	int		(*dev_ready)(struct mtd_info *mtd);
	void		(*select_chip)(struct mtd_info *mtd, int chip);
	void		*priv;
};

/* Some helpers to access the data structures */
static inline
struct platform_nand_chip *get_platform_nandchip(struct mtd_info *mtd)
{
	struct nand_chip *chip = mtd->priv;

	return chip->priv;
}

#endif /* __LINUX_MTD_NAND_H */