xref: /openbmc/u-boot/include/linux/mtd/nand.h (revision 46198754)
1 /*
2  *  linux/include/linux/mtd/nand.h
3  *
4  *  Copyright (c) 2000 David Woodhouse <dwmw2@infradead.org>
5  *                     Steven J. Hill <sjhill@realitydiluted.com>
6  *		       Thomas Gleixner <tglx@linutronix.de>
7  *
8  * This program is free software; you can redistribute it and/or modify
9  * it under the terms of the GNU General Public License version 2 as
10  * published by the Free Software Foundation.
11  *
12  * Info:
13  *	Contains standard defines and IDs for NAND flash devices
14  *
15  * Changelog:
16  *	See git changelog.
17  */
18 #ifndef __LINUX_MTD_NAND_H
19 #define __LINUX_MTD_NAND_H
20 
21 /* XXX U-BOOT XXX */
22 #if 0
23 #include <linux/wait.h>
24 #include <linux/spinlock.h>
25 #include <linux/mtd/mtd.h>
26 #endif
27 
28 #include "config.h"
29 
30 #include "linux/mtd/compat.h"
31 #include "linux/mtd/mtd.h"
32 #include "linux/mtd/bbm.h"
33 
34 
35 struct mtd_info;
36 struct nand_flash_dev;
37 /* Scan and identify a NAND device */
38 extern int nand_scan (struct mtd_info *mtd, int max_chips);
39 /* Separate phases of nand_scan(), allowing board driver to intervene
40  * and override command or ECC setup according to flash type */
41 extern int nand_scan_ident(struct mtd_info *mtd, int max_chips,
42 			   const struct nand_flash_dev *table);
43 extern int nand_scan_tail(struct mtd_info *mtd);
44 
45 /* Free resources held by the NAND device */
46 extern void nand_release (struct mtd_info *mtd);
47 
48 /* Internal helper for board drivers which need to override command function */
49 extern void nand_wait_ready(struct mtd_info *mtd);
50 
51 /* This constant declares the max. oobsize / page, which
52  * is supported now. If you add a chip with bigger oobsize/page
53  * adjust this accordingly.
54  */
55 #define NAND_MAX_OOBSIZE	218
56 #define NAND_MAX_PAGESIZE	4096
57 
58 /*
59  * Constants for hardware specific CLE/ALE/NCE function
60  *
61  * These are bits which can be or'ed to set/clear multiple
62  * bits in one go.
63  */
64 /* Select the chip by setting nCE to low */
65 #define NAND_NCE		0x01
66 /* Select the command latch by setting CLE to high */
67 #define NAND_CLE		0x02
68 /* Select the address latch by setting ALE to high */
69 #define NAND_ALE		0x04
70 
71 #define NAND_CTRL_CLE		(NAND_NCE | NAND_CLE)
72 #define NAND_CTRL_ALE		(NAND_NCE | NAND_ALE)
73 #define NAND_CTRL_CHANGE	0x80
74 
75 /*
76  * Standard NAND flash commands
77  */
78 #define NAND_CMD_READ0		0
79 #define NAND_CMD_READ1		1
80 #define NAND_CMD_RNDOUT		5
81 #define NAND_CMD_PAGEPROG	0x10
82 #define NAND_CMD_READOOB	0x50
83 #define NAND_CMD_ERASE1		0x60
84 #define NAND_CMD_STATUS		0x70
85 #define NAND_CMD_STATUS_MULTI	0x71
86 #define NAND_CMD_SEQIN		0x80
87 #define NAND_CMD_RNDIN		0x85
88 #define NAND_CMD_READID		0x90
89 #define NAND_CMD_PARAM		0xec
90 #define NAND_CMD_ERASE2		0xd0
91 #define NAND_CMD_RESET		0xff
92 
93 /* Extended commands for large page devices */
94 #define NAND_CMD_READSTART	0x30
95 #define NAND_CMD_RNDOUTSTART	0xE0
96 #define NAND_CMD_CACHEDPROG	0x15
97 
98 /* Extended commands for AG-AND device */
99 /*
100  * Note: the command for NAND_CMD_DEPLETE1 is really 0x00 but
101  *       there is no way to distinguish that from NAND_CMD_READ0
102  *       until the remaining sequence of commands has been completed
103  *       so add a high order bit and mask it off in the command.
104  */
105 #define NAND_CMD_DEPLETE1	0x100
106 #define NAND_CMD_DEPLETE2	0x38
107 #define NAND_CMD_STATUS_MULTI	0x71
108 #define NAND_CMD_STATUS_ERROR	0x72
109 /* multi-bank error status (banks 0-3) */
110 #define NAND_CMD_STATUS_ERROR0	0x73
111 #define NAND_CMD_STATUS_ERROR1	0x74
112 #define NAND_CMD_STATUS_ERROR2	0x75
113 #define NAND_CMD_STATUS_ERROR3	0x76
114 #define NAND_CMD_STATUS_RESET	0x7f
115 #define NAND_CMD_STATUS_CLEAR	0xff
116 
117 #define NAND_CMD_NONE		-1
118 
119 /* Status bits */
120 #define NAND_STATUS_FAIL	0x01
121 #define NAND_STATUS_FAIL_N1	0x02
122 #define NAND_STATUS_TRUE_READY	0x20
123 #define NAND_STATUS_READY	0x40
124 #define NAND_STATUS_WP		0x80
125 
126 /*
127  * Constants for ECC_MODES
128  */
129 typedef enum {
130 	NAND_ECC_NONE,
131 	NAND_ECC_SOFT,
132 	NAND_ECC_HW,
133 	NAND_ECC_HW_SYNDROME,
134 	NAND_ECC_HW_OOB_FIRST,
135 } nand_ecc_modes_t;
136 
137 /*
138  * Constants for Hardware ECC
139  */
140 /* Reset Hardware ECC for read */
141 #define NAND_ECC_READ		0
142 /* Reset Hardware ECC for write */
143 #define NAND_ECC_WRITE		1
144 /* Enable Hardware ECC before syndrom is read back from flash */
145 #define NAND_ECC_READSYN	2
146 
147 /* Bit mask for flags passed to do_nand_read_ecc */
148 #define NAND_GET_DEVICE		0x80
149 
150 
151 /* Option constants for bizarre disfunctionality and real
152 *  features
153 */
154 /* Chip can not auto increment pages */
155 #define NAND_NO_AUTOINCR	0x00000001
156 /* Buswitdh is 16 bit */
157 #define NAND_BUSWIDTH_16	0x00000002
158 /* Device supports partial programming without padding */
159 #define NAND_NO_PADDING		0x00000004
160 /* Chip has cache program function */
161 #define NAND_CACHEPRG		0x00000008
162 /* Chip has copy back function */
163 #define NAND_COPYBACK		0x00000010
164 /* AND Chip which has 4 banks and a confusing page / block
165  * assignment. See Renesas datasheet for further information */
166 #define NAND_IS_AND		0x00000020
167 /* Chip has a array of 4 pages which can be read without
168  * additional ready /busy waits */
169 #define NAND_4PAGE_ARRAY	0x00000040
170 /* Chip requires that BBT is periodically rewritten to prevent
171  * bits from adjacent blocks from 'leaking' in altering data.
172  * This happens with the Renesas AG-AND chips, possibly others.  */
173 #define BBT_AUTO_REFRESH	0x00000080
174 /* Chip does not require ready check on read. True
175  * for all large page devices, as they do not support
176  * autoincrement.*/
177 #define NAND_NO_READRDY		0x00000100
178 /* Chip does not allow subpage writes */
179 #define NAND_NO_SUBPAGE_WRITE	0x00000200
180 
181 
182 /* Options valid for Samsung large page devices */
183 #define NAND_SAMSUNG_LP_OPTIONS \
184 	(NAND_NO_PADDING | NAND_CACHEPRG | NAND_COPYBACK)
185 
186 /* Macros to identify the above */
187 #define NAND_CANAUTOINCR(chip) (!(chip->options & NAND_NO_AUTOINCR))
188 #define NAND_MUST_PAD(chip) (!(chip->options & NAND_NO_PADDING))
189 #define NAND_HAS_CACHEPROG(chip) ((chip->options & NAND_CACHEPRG))
190 #define NAND_HAS_COPYBACK(chip) ((chip->options & NAND_COPYBACK))
191 /* Large page NAND with SOFT_ECC should support subpage reads */
192 #define NAND_SUBPAGE_READ(chip) ((chip->ecc.mode == NAND_ECC_SOFT) \
193 					&& (chip->page_shift > 9))
194 
195 /* Mask to zero out the chip options, which come from the id table */
196 #define NAND_CHIPOPTIONS_MSK	(0x0000ffff & ~NAND_NO_AUTOINCR)
197 
198 /* Non chip related options */
199 /* Use a flash based bad block table. This option is passed to the
200  * default bad block table function. */
201 #define NAND_USE_FLASH_BBT	0x00010000
202 /* This option skips the bbt scan during initialization. */
203 #define NAND_SKIP_BBTSCAN	0x00020000
204 /* This option is defined if the board driver allocates its own buffers
205    (e.g. because it needs them DMA-coherent */
206 #define NAND_OWN_BUFFERS	0x00040000
207 /* Options set by nand scan */
208 /* bbt has already been read */
209 #define NAND_BBT_SCANNED	0x40000000
210 /* Nand scan has allocated controller struct */
211 #define NAND_CONTROLLER_ALLOC	0x80000000
212 
213 /* Cell info constants */
214 #define NAND_CI_CHIPNR_MSK	0x03
215 #define NAND_CI_CELLTYPE_MSK	0x0C
216 
217 /* Keep gcc happy */
218 struct nand_chip;
219 
220 /**
221  * struct nand_hw_control - Control structure for hardware controller (e.g ECC generator) shared among independent devices
222  * @lock:               protection lock
223  * @active:		the mtd device which holds the controller currently
224  * @wq:			wait queue to sleep on if a NAND operation is in progress
225  *                      used instead of the per chip wait queue when a hw controller is available
226  */
227 struct nand_hw_control {
228 /* XXX U-BOOT XXX */
229 #if 0
230 	spinlock_t	 lock;
231 	wait_queue_head_t wq;
232 #endif
233 	struct nand_chip *active;
234 };
235 
236 /**
237  * struct nand_ecc_ctrl - Control structure for ecc
238  * @mode:	ecc mode
239  * @steps:	number of ecc steps per page
240  * @size:	data bytes per ecc step
241  * @bytes:	ecc bytes per step
242  * @total:	total number of ecc bytes per page
243  * @prepad:	padding information for syndrome based ecc generators
244  * @postpad:	padding information for syndrome based ecc generators
245  * @layout:	ECC layout control struct pointer
246  * @hwctl:	function to control hardware ecc generator. Must only
247  *		be provided if an hardware ECC is available
248  * @calculate:	function for ecc calculation or readback from ecc hardware
249  * @correct:	function for ecc correction, matching to ecc generator (sw/hw)
250  * @read_page_raw:	function to read a raw page without ECC
251  * @write_page_raw:	function to write a raw page without ECC
252  * @read_page:	function to read a page according to the ecc generator requirements
253  * @write_page:	function to write a page according to the ecc generator requirements
254  * @read_oob:	function to read chip OOB data
255  * @write_oob:	function to write chip OOB data
256  */
257 struct nand_ecc_ctrl {
258 	nand_ecc_modes_t	mode;
259 	int			steps;
260 	int			size;
261 	int			bytes;
262 	int			total;
263 	int			prepad;
264 	int			postpad;
265 	struct nand_ecclayout	*layout;
266 	void			(*hwctl)(struct mtd_info *mtd, int mode);
267 	int			(*calculate)(struct mtd_info *mtd,
268 					     const uint8_t *dat,
269 					     uint8_t *ecc_code);
270 	int			(*correct)(struct mtd_info *mtd, uint8_t *dat,
271 					   uint8_t *read_ecc,
272 					   uint8_t *calc_ecc);
273 	int			(*read_page_raw)(struct mtd_info *mtd,
274 						 struct nand_chip *chip,
275 						 uint8_t *buf, int page);
276 	void			(*write_page_raw)(struct mtd_info *mtd,
277 						  struct nand_chip *chip,
278 						  const uint8_t *buf);
279 	int			(*read_page)(struct mtd_info *mtd,
280 					     struct nand_chip *chip,
281 					     uint8_t *buf, int page);
282 	int			(*read_subpage)(struct mtd_info *mtd,
283 					     struct nand_chip *chip,
284 					     uint32_t offs, uint32_t len,
285 					     uint8_t *buf);
286 	void			(*write_page)(struct mtd_info *mtd,
287 					      struct nand_chip *chip,
288 					      const uint8_t *buf);
289 	int			(*read_oob)(struct mtd_info *mtd,
290 					    struct nand_chip *chip,
291 					    int page,
292 					    int sndcmd);
293 	int			(*write_oob)(struct mtd_info *mtd,
294 					     struct nand_chip *chip,
295 					     int page);
296 };
297 
298 /**
299  * struct nand_buffers - buffer structure for read/write
300  * @ecccalc:	buffer for calculated ecc
301  * @ecccode:	buffer for ecc read from flash
302  * @databuf:	buffer for data - dynamically sized
303  *
304  * Do not change the order of buffers. databuf and oobrbuf must be in
305  * consecutive order.
306  */
307 struct nand_buffers {
308 	uint8_t	ecccalc[NAND_MAX_OOBSIZE];
309 	uint8_t	ecccode[NAND_MAX_OOBSIZE];
310 	uint8_t databuf[NAND_MAX_PAGESIZE + NAND_MAX_OOBSIZE];
311 };
312 
313 /**
314  * struct nand_chip - NAND Private Flash Chip Data
315  * @IO_ADDR_R:		[BOARDSPECIFIC] address to read the 8 I/O lines of the flash device
316  * @IO_ADDR_W:		[BOARDSPECIFIC] address to write the 8 I/O lines of the flash device
317  * @read_byte:		[REPLACEABLE] read one byte from the chip
318  * @read_word:		[REPLACEABLE] read one word from the chip
319  * @write_buf:		[REPLACEABLE] write data from the buffer to the chip
320  * @read_buf:		[REPLACEABLE] read data from the chip into the buffer
321  * @verify_buf:		[REPLACEABLE] verify buffer contents against the chip data
322  * @select_chip:	[REPLACEABLE] select chip nr
323  * @block_bad:		[REPLACEABLE] check, if the block is bad
324  * @block_markbad:	[REPLACEABLE] mark the block bad
325  * @cmd_ctrl:		[BOARDSPECIFIC] hardwarespecific funtion for controlling
326  *			ALE/CLE/nCE. Also used to write command and address
327  * @dev_ready:		[BOARDSPECIFIC] hardwarespecific function for accesing device ready/busy line
328  *			If set to NULL no access to ready/busy is available and the ready/busy information
329  *			is read from the chip status register
330  * @cmdfunc:		[REPLACEABLE] hardwarespecific function for writing commands to the chip
331  * @waitfunc:		[REPLACEABLE] hardwarespecific function for wait on ready
332  * @ecc:		[BOARDSPECIFIC] ecc control ctructure
333  * @buffers:		buffer structure for read/write
334  * @hwcontrol:		platform-specific hardware control structure
335  * @ops:		oob operation operands
336  * @erase_cmd:		[INTERN] erase command write function, selectable due to AND support
337  * @scan_bbt:		[REPLACEABLE] function to scan bad block table
338  * @chip_delay:		[BOARDSPECIFIC] chip dependent delay for transfering data from array to read regs (tR)
339  * @wq:			[INTERN] wait queue to sleep on if a NAND operation is in progress
340  * @state:		[INTERN] the current state of the NAND device
341  * @oob_poi:		poison value buffer
342  * @page_shift:		[INTERN] number of address bits in a page (column address bits)
343  * @phys_erase_shift:	[INTERN] number of address bits in a physical eraseblock
344  * @bbt_erase_shift:	[INTERN] number of address bits in a bbt entry
345  * @chip_shift:		[INTERN] number of address bits in one chip
346  * @datbuf:		[INTERN] internal buffer for one page + oob
347  * @oobbuf:		[INTERN] oob buffer for one eraseblock
348  * @oobdirty:		[INTERN] indicates that oob_buf must be reinitialized
349  * @data_poi:		[INTERN] pointer to a data buffer
350  * @options:		[BOARDSPECIFIC] various chip options. They can partly be set to inform nand_scan about
351  *			special functionality. See the defines for further explanation
352  * @badblockpos:	[INTERN] position of the bad block marker in the oob area
353  * @cellinfo:		[INTERN] MLC/multichip data from chip ident
354  * @numchips:		[INTERN] number of physical chips
355  * @chipsize:		[INTERN] the size of one chip for multichip arrays
356  * @pagemask:		[INTERN] page number mask = number of (pages / chip) - 1
357  * @pagebuf:		[INTERN] holds the pagenumber which is currently in data_buf
358  * @subpagesize:	[INTERN] holds the subpagesize
359  * @ecclayout:		[REPLACEABLE] the default ecc placement scheme
360  * @bbt:		[INTERN] bad block table pointer
361  * @bbt_td:		[REPLACEABLE] bad block table descriptor for flash lookup
362  * @bbt_md:		[REPLACEABLE] bad block table mirror descriptor
363  * @badblock_pattern:	[REPLACEABLE] bad block scan pattern used for initial bad block scan
364  * @controller:		[REPLACEABLE] a pointer to a hardware controller structure
365  *			which is shared among multiple independend devices
366  * @priv:		[OPTIONAL] pointer to private chip date
367  * @errstat:		[OPTIONAL] hardware specific function to perform additional error status checks
368  *			(determine if errors are correctable)
369  * @write_page:		[REPLACEABLE] High-level page write function
370  */
371 
372 struct nand_chip {
373 	void  __iomem	*IO_ADDR_R;
374 	void  __iomem	*IO_ADDR_W;
375 
376 	uint8_t		(*read_byte)(struct mtd_info *mtd);
377 	u16		(*read_word)(struct mtd_info *mtd);
378 	void		(*write_buf)(struct mtd_info *mtd, const uint8_t *buf, int len);
379 	void		(*read_buf)(struct mtd_info *mtd, uint8_t *buf, int len);
380 	int		(*verify_buf)(struct mtd_info *mtd, const uint8_t *buf, int len);
381 	void		(*select_chip)(struct mtd_info *mtd, int chip);
382 	int		(*block_bad)(struct mtd_info *mtd, loff_t ofs, int getchip);
383 	int		(*block_markbad)(struct mtd_info *mtd, loff_t ofs);
384 	void		(*cmd_ctrl)(struct mtd_info *mtd, int dat,
385 				    unsigned int ctrl);
386 	int		(*dev_ready)(struct mtd_info *mtd);
387 	void		(*cmdfunc)(struct mtd_info *mtd, unsigned command, int column, int page_addr);
388 	int		(*waitfunc)(struct mtd_info *mtd, struct nand_chip *this);
389 	void		(*erase_cmd)(struct mtd_info *mtd, int page);
390 	int		(*scan_bbt)(struct mtd_info *mtd);
391 	int		(*errstat)(struct mtd_info *mtd, struct nand_chip *this, int state, int status, int page);
392 	int		(*write_page)(struct mtd_info *mtd, struct nand_chip *chip,
393 				      const uint8_t *buf, int page, int cached, int raw);
394 
395 	int		chip_delay;
396 	unsigned int	options;
397 
398 	int		page_shift;
399 	int		phys_erase_shift;
400 	int		bbt_erase_shift;
401 	int		chip_shift;
402 	int		numchips;
403 	uint64_t	chipsize;
404 	int		pagemask;
405 	int		pagebuf;
406 	int		subpagesize;
407 	uint8_t		cellinfo;
408 	int		badblockpos;
409 
410 	int 		state;
411 
412 	uint8_t		*oob_poi;
413 	struct nand_hw_control  *controller;
414 	struct nand_ecclayout	*ecclayout;
415 
416 	struct nand_ecc_ctrl ecc;
417 	struct nand_buffers *buffers;
418 
419 	struct nand_hw_control hwcontrol;
420 
421 	struct mtd_oob_ops ops;
422 
423 	uint8_t		*bbt;
424 	struct nand_bbt_descr	*bbt_td;
425 	struct nand_bbt_descr	*bbt_md;
426 
427 	struct nand_bbt_descr	*badblock_pattern;
428 
429 	void		*priv;
430 };
431 
432 /*
433  * NAND Flash Manufacturer ID Codes
434  */
435 #define NAND_MFR_TOSHIBA	0x98
436 #define NAND_MFR_SAMSUNG	0xec
437 #define NAND_MFR_FUJITSU	0x04
438 #define NAND_MFR_NATIONAL	0x8f
439 #define NAND_MFR_RENESAS	0x07
440 #define NAND_MFR_STMICRO	0x20
441 #define NAND_MFR_HYNIX		0xad
442 #define NAND_MFR_MICRON		0x2c
443 #define NAND_MFR_AMD		0x01
444 
445 /**
446  * struct nand_flash_dev - NAND Flash Device ID Structure
447  * @name:	Identify the device type
448  * @id:		device ID code
449  * @pagesize:	Pagesize in bytes. Either 256 or 512 or 0
450  *		If the pagesize is 0, then the real pagesize
451  *		and the eraseize are determined from the
452  *		extended id bytes in the chip
453  * @erasesize:	Size of an erase block in the flash device.
454  * @chipsize:	Total chipsize in Mega Bytes
455  * @options:	Bitfield to store chip relevant options
456  */
457 struct nand_flash_dev {
458 	char *name;
459 	int id;
460 	unsigned long pagesize;
461 	unsigned long chipsize;
462 	unsigned long erasesize;
463 	unsigned long options;
464 };
465 
466 /**
467  * struct nand_manufacturers - NAND Flash Manufacturer ID Structure
468  * @name:	Manufacturer name
469  * @id:		manufacturer ID code of device.
470 */
471 struct nand_manufacturers {
472 	int id;
473 	char * name;
474 };
475 
476 extern const struct nand_flash_dev nand_flash_ids[];
477 extern const struct nand_manufacturers nand_manuf_ids[];
478 
479 extern int nand_scan_bbt(struct mtd_info *mtd, struct nand_bbt_descr *bd);
480 extern int nand_update_bbt(struct mtd_info *mtd, loff_t offs);
481 extern int nand_default_bbt(struct mtd_info *mtd);
482 extern int nand_isbad_bbt(struct mtd_info *mtd, loff_t offs, int allowbbt);
483 extern int nand_erase_nand(struct mtd_info *mtd, struct erase_info *instr,
484 			   int allowbbt);
485 extern int nand_do_read(struct mtd_info *mtd, loff_t from, size_t len,
486 			size_t * retlen, uint8_t * buf);
487 
488 /*
489 * Constants for oob configuration
490 */
491 #define NAND_SMALL_BADBLOCK_POS		5
492 #define NAND_LARGE_BADBLOCK_POS		0
493 
494 /**
495  * struct platform_nand_chip - chip level device structure
496  * @nr_chips:		max. number of chips to scan for
497  * @chip_offset:	chip number offset
498  * @nr_partitions:	number of partitions pointed to by partitions (or zero)
499  * @partitions:		mtd partition list
500  * @chip_delay:		R/B delay value in us
501  * @options:		Option flags, e.g. 16bit buswidth
502  * @ecclayout:		ecc layout info structure
503  * @part_probe_types:	NULL-terminated array of probe types
504  * @priv:		hardware controller specific settings
505  */
506 struct platform_nand_chip {
507 	int			nr_chips;
508 	int			chip_offset;
509 	int			nr_partitions;
510 	struct mtd_partition	*partitions;
511 	struct nand_ecclayout	*ecclayout;
512 	int			chip_delay;
513 	unsigned int		options;
514 	const char		**part_probe_types;
515 	void			*priv;
516 };
517 
518 /**
519  * struct platform_nand_ctrl - controller level device structure
520  * @hwcontrol:		platform specific hardware control structure
521  * @dev_ready:		platform specific function to read ready/busy pin
522  * @select_chip:	platform specific chip select function
523  * @cmd_ctrl:		platform specific function for controlling
524  *			ALE/CLE/nCE. Also used to write command and address
525  * @priv:		private data to transport driver specific settings
526  *
527  * All fields are optional and depend on the hardware driver requirements
528  */
529 struct platform_nand_ctrl {
530 	void		(*hwcontrol)(struct mtd_info *mtd, int cmd);
531 	int		(*dev_ready)(struct mtd_info *mtd);
532 	void		(*select_chip)(struct mtd_info *mtd, int chip);
533 	void		(*cmd_ctrl)(struct mtd_info *mtd, int dat,
534 				    unsigned int ctrl);
535 	void		*priv;
536 };
537 
538 /**
539  * struct platform_nand_data - container structure for platform-specific data
540  * @chip:		chip level chip structure
541  * @ctrl:		controller level device structure
542  */
543 struct platform_nand_data {
544 	struct platform_nand_chip	chip;
545 	struct platform_nand_ctrl	ctrl;
546 };
547 
548 /* Some helpers to access the data structures */
549 static inline
550 struct platform_nand_chip *get_platform_nandchip(struct mtd_info *mtd)
551 {
552 	struct nand_chip *chip = mtd->priv;
553 
554 	return chip->priv;
555 }
556 
557 #endif /* __LINUX_MTD_NAND_H */
558