xref: /openbmc/u-boot/include/linux/mtd/nand.h (revision 38dba0c2ff685e3f8276a236bd70eaa09c84ead5)
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 /* Scan and identify a NAND device */
37 extern int nand_scan (struct mtd_info *mtd, int max_chips);
38 /* Separate phases of nand_scan(), allowing board driver to intervene
39  * and override command or ECC setup according to flash type */
40 extern int nand_scan_ident(struct mtd_info *mtd, int max_chips);
41 extern int nand_scan_tail(struct mtd_info *mtd);
42 
43 /* Free resources held by the NAND device */
44 extern void nand_release (struct mtd_info *mtd);
45 
46 /* Internal helper for board drivers which need to override command function */
47 extern void nand_wait_ready(struct mtd_info *mtd);
48 
49 /* This constant declares the max. oobsize / page, which
50  * is supported now. If you add a chip with bigger oobsize/page
51  * adjust this accordingly.
52  */
53 #define NAND_MAX_OOBSIZE	218
54 #define NAND_MAX_PAGESIZE	4096
55 
56 /*
57  * Constants for hardware specific CLE/ALE/NCE function
58  *
59  * These are bits which can be or'ed to set/clear multiple
60  * bits in one go.
61  */
62 /* Select the chip by setting nCE to low */
63 #define NAND_NCE		0x01
64 /* Select the command latch by setting CLE to high */
65 #define NAND_CLE		0x02
66 /* Select the address latch by setting ALE to high */
67 #define NAND_ALE		0x04
68 
69 #define NAND_CTRL_CLE		(NAND_NCE | NAND_CLE)
70 #define NAND_CTRL_ALE		(NAND_NCE | NAND_ALE)
71 #define NAND_CTRL_CHANGE	0x80
72 
73 /*
74  * Standard NAND flash commands
75  */
76 #define NAND_CMD_READ0		0
77 #define NAND_CMD_READ1		1
78 #define NAND_CMD_RNDOUT		5
79 #define NAND_CMD_PAGEPROG	0x10
80 #define NAND_CMD_READOOB	0x50
81 #define NAND_CMD_ERASE1		0x60
82 #define NAND_CMD_STATUS		0x70
83 #define NAND_CMD_STATUS_MULTI	0x71
84 #define NAND_CMD_SEQIN		0x80
85 #define NAND_CMD_RNDIN		0x85
86 #define NAND_CMD_READID		0x90
87 #define NAND_CMD_PARAM		0xec
88 #define NAND_CMD_ERASE2		0xd0
89 #define NAND_CMD_RESET		0xff
90 
91 /* Extended commands for large page devices */
92 #define NAND_CMD_READSTART	0x30
93 #define NAND_CMD_RNDOUTSTART	0xE0
94 #define NAND_CMD_CACHEDPROG	0x15
95 
96 /* Extended commands for AG-AND device */
97 /*
98  * Note: the command for NAND_CMD_DEPLETE1 is really 0x00 but
99  *       there is no way to distinguish that from NAND_CMD_READ0
100  *       until the remaining sequence of commands has been completed
101  *       so add a high order bit and mask it off in the command.
102  */
103 #define NAND_CMD_DEPLETE1	0x100
104 #define NAND_CMD_DEPLETE2	0x38
105 #define NAND_CMD_STATUS_MULTI	0x71
106 #define NAND_CMD_STATUS_ERROR	0x72
107 /* multi-bank error status (banks 0-3) */
108 #define NAND_CMD_STATUS_ERROR0	0x73
109 #define NAND_CMD_STATUS_ERROR1	0x74
110 #define NAND_CMD_STATUS_ERROR2	0x75
111 #define NAND_CMD_STATUS_ERROR3	0x76
112 #define NAND_CMD_STATUS_RESET	0x7f
113 #define NAND_CMD_STATUS_CLEAR	0xff
114 
115 #define NAND_CMD_NONE		-1
116 
117 /* Status bits */
118 #define NAND_STATUS_FAIL	0x01
119 #define NAND_STATUS_FAIL_N1	0x02
120 #define NAND_STATUS_TRUE_READY	0x20
121 #define NAND_STATUS_READY	0x40
122 #define NAND_STATUS_WP		0x80
123 
124 /*
125  * Constants for ECC_MODES
126  */
127 typedef enum {
128 	NAND_ECC_NONE,
129 	NAND_ECC_SOFT,
130 	NAND_ECC_HW,
131 	NAND_ECC_HW_SYNDROME,
132 	NAND_ECC_HW_OOB_FIRST,
133 } nand_ecc_modes_t;
134 
135 /*
136  * Constants for Hardware ECC
137  */
138 /* Reset Hardware ECC for read */
139 #define NAND_ECC_READ		0
140 /* Reset Hardware ECC for write */
141 #define NAND_ECC_WRITE		1
142 /* Enable Hardware ECC before syndrom is read back from flash */
143 #define NAND_ECC_READSYN	2
144 
145 /* Bit mask for flags passed to do_nand_read_ecc */
146 #define NAND_GET_DEVICE		0x80
147 
148 
149 /* Option constants for bizarre disfunctionality and real
150 *  features
151 */
152 /* Chip can not auto increment pages */
153 #define NAND_NO_AUTOINCR	0x00000001
154 /* Buswitdh is 16 bit */
155 #define NAND_BUSWIDTH_16	0x00000002
156 /* Device supports partial programming without padding */
157 #define NAND_NO_PADDING		0x00000004
158 /* Chip has cache program function */
159 #define NAND_CACHEPRG		0x00000008
160 /* Chip has copy back function */
161 #define NAND_COPYBACK		0x00000010
162 /* AND Chip which has 4 banks and a confusing page / block
163  * assignment. See Renesas datasheet for further information */
164 #define NAND_IS_AND		0x00000020
165 /* Chip has a array of 4 pages which can be read without
166  * additional ready /busy waits */
167 #define NAND_4PAGE_ARRAY	0x00000040
168 /* Chip requires that BBT is periodically rewritten to prevent
169  * bits from adjacent blocks from 'leaking' in altering data.
170  * This happens with the Renesas AG-AND chips, possibly others.  */
171 #define BBT_AUTO_REFRESH	0x00000080
172 /* Chip does not require ready check on read. True
173  * for all large page devices, as they do not support
174  * autoincrement.*/
175 #define NAND_NO_READRDY		0x00000100
176 /* Chip does not allow subpage writes */
177 #define NAND_NO_SUBPAGE_WRITE	0x00000200
178 
179 
180 /* Options valid for Samsung large page devices */
181 #define NAND_SAMSUNG_LP_OPTIONS \
182 	(NAND_NO_PADDING | NAND_CACHEPRG | NAND_COPYBACK)
183 
184 /* Macros to identify the above */
185 #define NAND_CANAUTOINCR(chip) (!(chip->options & NAND_NO_AUTOINCR))
186 #define NAND_MUST_PAD(chip) (!(chip->options & NAND_NO_PADDING))
187 #define NAND_HAS_CACHEPROG(chip) ((chip->options & NAND_CACHEPRG))
188 #define NAND_HAS_COPYBACK(chip) ((chip->options & NAND_COPYBACK))
189 /* Large page NAND with SOFT_ECC should support subpage reads */
190 #define NAND_SUBPAGE_READ(chip) ((chip->ecc.mode == NAND_ECC_SOFT) \
191 					&& (chip->page_shift > 9))
192 
193 /* Mask to zero out the chip options, which come from the id table */
194 #define NAND_CHIPOPTIONS_MSK	(0x0000ffff & ~NAND_NO_AUTOINCR)
195 
196 /* Non chip related options */
197 /* Use a flash based bad block table. This option is passed to the
198  * default bad block table function. */
199 #define NAND_USE_FLASH_BBT	0x00010000
200 /* This option skips the bbt scan during initialization. */
201 #define NAND_SKIP_BBTSCAN	0x00020000
202 /* This option is defined if the board driver allocates its own buffers
203    (e.g. because it needs them DMA-coherent */
204 #define NAND_OWN_BUFFERS	0x00040000
205 /* Options set by nand scan */
206 /* bbt has already been read */
207 #define NAND_BBT_SCANNED	0x40000000
208 /* Nand scan has allocated controller struct */
209 #define NAND_CONTROLLER_ALLOC	0x80000000
210 
211 /* Cell info constants */
212 #define NAND_CI_CHIPNR_MSK	0x03
213 #define NAND_CI_CELLTYPE_MSK	0x0C
214 
215 /* Keep gcc happy */
216 struct nand_chip;
217 
218 /**
219  * struct nand_hw_control - Control structure for hardware controller (e.g ECC generator) shared among independent devices
220  * @lock:               protection lock
221  * @active:		the mtd device which holds the controller currently
222  * @wq:			wait queue to sleep on if a NAND operation is in progress
223  *                      used instead of the per chip wait queue when a hw controller is available
224  */
225 struct nand_hw_control {
226 /* XXX U-BOOT XXX */
227 #if 0
228 	spinlock_t	 lock;
229 	wait_queue_head_t wq;
230 #endif
231 	struct nand_chip *active;
232 };
233 
234 /**
235  * struct nand_ecc_ctrl - Control structure for ecc
236  * @mode:	ecc mode
237  * @steps:	number of ecc steps per page
238  * @size:	data bytes per ecc step
239  * @bytes:	ecc bytes per step
240  * @total:	total number of ecc bytes per page
241  * @prepad:	padding information for syndrome based ecc generators
242  * @postpad:	padding information for syndrome based ecc generators
243  * @layout:	ECC layout control struct pointer
244  * @hwctl:	function to control hardware ecc generator. Must only
245  *		be provided if an hardware ECC is available
246  * @calculate:	function for ecc calculation or readback from ecc hardware
247  * @correct:	function for ecc correction, matching to ecc generator (sw/hw)
248  * @read_page_raw:	function to read a raw page without ECC
249  * @write_page_raw:	function to write a raw page without ECC
250  * @read_page:	function to read a page according to the ecc generator requirements
251  * @write_page:	function to write a page according to the ecc generator requirements
252  * @read_oob:	function to read chip OOB data
253  * @write_oob:	function to write chip OOB data
254  */
255 struct nand_ecc_ctrl {
256 	nand_ecc_modes_t	mode;
257 	int			steps;
258 	int			size;
259 	int			bytes;
260 	int			total;
261 	int			prepad;
262 	int			postpad;
263 	struct nand_ecclayout	*layout;
264 	void			(*hwctl)(struct mtd_info *mtd, int mode);
265 	int			(*calculate)(struct mtd_info *mtd,
266 					     const uint8_t *dat,
267 					     uint8_t *ecc_code);
268 	int			(*correct)(struct mtd_info *mtd, uint8_t *dat,
269 					   uint8_t *read_ecc,
270 					   uint8_t *calc_ecc);
271 	int			(*read_page_raw)(struct mtd_info *mtd,
272 						 struct nand_chip *chip,
273 						 uint8_t *buf, int page);
274 	void			(*write_page_raw)(struct mtd_info *mtd,
275 						  struct nand_chip *chip,
276 						  const uint8_t *buf);
277 	int			(*read_page)(struct mtd_info *mtd,
278 					     struct nand_chip *chip,
279 					     uint8_t *buf, int page);
280 	int			(*read_subpage)(struct mtd_info *mtd,
281 					     struct nand_chip *chip,
282 					     uint32_t offs, uint32_t len,
283 					     uint8_t *buf);
284 	void			(*write_page)(struct mtd_info *mtd,
285 					      struct nand_chip *chip,
286 					      const uint8_t *buf);
287 	int			(*read_oob)(struct mtd_info *mtd,
288 					    struct nand_chip *chip,
289 					    int page,
290 					    int sndcmd);
291 	int			(*write_oob)(struct mtd_info *mtd,
292 					     struct nand_chip *chip,
293 					     int page);
294 };
295 
296 /**
297  * struct nand_buffers - buffer structure for read/write
298  * @ecccalc:	buffer for calculated ecc
299  * @ecccode:	buffer for ecc read from flash
300  * @databuf:	buffer for data - dynamically sized
301  *
302  * Do not change the order of buffers. databuf and oobrbuf must be in
303  * consecutive order.
304  */
305 struct nand_buffers {
306 	uint8_t	ecccalc[NAND_MAX_OOBSIZE];
307 	uint8_t	ecccode[NAND_MAX_OOBSIZE];
308 	uint8_t databuf[NAND_MAX_PAGESIZE + NAND_MAX_OOBSIZE];
309 };
310 
311 /**
312  * struct nand_chip - NAND Private Flash Chip Data
313  * @IO_ADDR_R:		[BOARDSPECIFIC] address to read the 8 I/O lines of the flash device
314  * @IO_ADDR_W:		[BOARDSPECIFIC] address to write the 8 I/O lines of the flash device
315  * @read_byte:		[REPLACEABLE] read one byte from the chip
316  * @read_word:		[REPLACEABLE] read one word from the chip
317  * @write_buf:		[REPLACEABLE] write data from the buffer to the chip
318  * @read_buf:		[REPLACEABLE] read data from the chip into the buffer
319  * @verify_buf:		[REPLACEABLE] verify buffer contents against the chip data
320  * @select_chip:	[REPLACEABLE] select chip nr
321  * @block_bad:		[REPLACEABLE] check, if the block is bad
322  * @block_markbad:	[REPLACEABLE] mark the block bad
323  * @cmd_ctrl:		[BOARDSPECIFIC] hardwarespecific funtion for controlling
324  *			ALE/CLE/nCE. Also used to write command and address
325  * @dev_ready:		[BOARDSPECIFIC] hardwarespecific function for accesing device ready/busy line
326  *			If set to NULL no access to ready/busy is available and the ready/busy information
327  *			is read from the chip status register
328  * @cmdfunc:		[REPLACEABLE] hardwarespecific function for writing commands to the chip
329  * @waitfunc:		[REPLACEABLE] hardwarespecific function for wait on ready
330  * @ecc:		[BOARDSPECIFIC] ecc control ctructure
331  * @buffers:		buffer structure for read/write
332  * @hwcontrol:		platform-specific hardware control structure
333  * @ops:		oob operation operands
334  * @erase_cmd:		[INTERN] erase command write function, selectable due to AND support
335  * @scan_bbt:		[REPLACEABLE] function to scan bad block table
336  * @chip_delay:		[BOARDSPECIFIC] chip dependent delay for transfering data from array to read regs (tR)
337  * @wq:			[INTERN] wait queue to sleep on if a NAND operation is in progress
338  * @state:		[INTERN] the current state of the NAND device
339  * @oob_poi:		poison value buffer
340  * @page_shift:		[INTERN] number of address bits in a page (column address bits)
341  * @phys_erase_shift:	[INTERN] number of address bits in a physical eraseblock
342  * @bbt_erase_shift:	[INTERN] number of address bits in a bbt entry
343  * @chip_shift:		[INTERN] number of address bits in one chip
344  * @datbuf:		[INTERN] internal buffer for one page + oob
345  * @oobbuf:		[INTERN] oob buffer for one eraseblock
346  * @oobdirty:		[INTERN] indicates that oob_buf must be reinitialized
347  * @data_poi:		[INTERN] pointer to a data buffer
348  * @options:		[BOARDSPECIFIC] various chip options. They can partly be set to inform nand_scan about
349  *			special functionality. See the defines for further explanation
350  * @badblockpos:	[INTERN] position of the bad block marker in the oob area
351  * @cellinfo:		[INTERN] MLC/multichip data from chip ident
352  * @numchips:		[INTERN] number of physical chips
353  * @chipsize:		[INTERN] the size of one chip for multichip arrays
354  * @pagemask:		[INTERN] page number mask = number of (pages / chip) - 1
355  * @pagebuf:		[INTERN] holds the pagenumber which is currently in data_buf
356  * @subpagesize:	[INTERN] holds the subpagesize
357  * @ecclayout:		[REPLACEABLE] the default ecc placement scheme
358  * @bbt:		[INTERN] bad block table pointer
359  * @bbt_td:		[REPLACEABLE] bad block table descriptor for flash lookup
360  * @bbt_md:		[REPLACEABLE] bad block table mirror descriptor
361  * @badblock_pattern:	[REPLACEABLE] bad block scan pattern used for initial bad block scan
362  * @controller:		[REPLACEABLE] a pointer to a hardware controller structure
363  *			which is shared among multiple independend devices
364  * @priv:		[OPTIONAL] pointer to private chip date
365  * @errstat:		[OPTIONAL] hardware specific function to perform additional error status checks
366  *			(determine if errors are correctable)
367  * @write_page:		[REPLACEABLE] High-level page write function
368  */
369 
370 struct nand_chip {
371 	void  __iomem	*IO_ADDR_R;
372 	void  __iomem	*IO_ADDR_W;
373 
374 	uint8_t		(*read_byte)(struct mtd_info *mtd);
375 	u16		(*read_word)(struct mtd_info *mtd);
376 	void		(*write_buf)(struct mtd_info *mtd, const uint8_t *buf, int len);
377 	void		(*read_buf)(struct mtd_info *mtd, uint8_t *buf, int len);
378 	int		(*verify_buf)(struct mtd_info *mtd, const uint8_t *buf, int len);
379 	void		(*select_chip)(struct mtd_info *mtd, int chip);
380 	int		(*block_bad)(struct mtd_info *mtd, loff_t ofs, int getchip);
381 	int		(*block_markbad)(struct mtd_info *mtd, loff_t ofs);
382 	void		(*cmd_ctrl)(struct mtd_info *mtd, int dat,
383 				    unsigned int ctrl);
384 	int		(*dev_ready)(struct mtd_info *mtd);
385 	void		(*cmdfunc)(struct mtd_info *mtd, unsigned command, int column, int page_addr);
386 	int		(*waitfunc)(struct mtd_info *mtd, struct nand_chip *this);
387 	void		(*erase_cmd)(struct mtd_info *mtd, int page);
388 	int		(*scan_bbt)(struct mtd_info *mtd);
389 	int		(*errstat)(struct mtd_info *mtd, struct nand_chip *this, int state, int status, int page);
390 	int		(*write_page)(struct mtd_info *mtd, struct nand_chip *chip,
391 				      const uint8_t *buf, int page, int cached, int raw);
392 
393 	int		chip_delay;
394 	unsigned int	options;
395 
396 	int		page_shift;
397 	int		phys_erase_shift;
398 	int		bbt_erase_shift;
399 	int		chip_shift;
400 	int		numchips;
401 	uint64_t	chipsize;
402 	int		pagemask;
403 	int		pagebuf;
404 	int		subpagesize;
405 	uint8_t		cellinfo;
406 	int		badblockpos;
407 
408 	int 		state;
409 
410 	uint8_t		*oob_poi;
411 	struct nand_hw_control  *controller;
412 	struct nand_ecclayout	*ecclayout;
413 
414 	struct nand_ecc_ctrl ecc;
415 	struct nand_buffers *buffers;
416 
417 	struct nand_hw_control hwcontrol;
418 
419 	struct mtd_oob_ops ops;
420 
421 	uint8_t		*bbt;
422 	struct nand_bbt_descr	*bbt_td;
423 	struct nand_bbt_descr	*bbt_md;
424 
425 	struct nand_bbt_descr	*badblock_pattern;
426 
427 	void		*priv;
428 };
429 
430 /*
431  * NAND Flash Manufacturer ID Codes
432  */
433 #define NAND_MFR_TOSHIBA	0x98
434 #define NAND_MFR_SAMSUNG	0xec
435 #define NAND_MFR_FUJITSU	0x04
436 #define NAND_MFR_NATIONAL	0x8f
437 #define NAND_MFR_RENESAS	0x07
438 #define NAND_MFR_STMICRO	0x20
439 #define NAND_MFR_HYNIX		0xad
440 #define NAND_MFR_MICRON		0x2c
441 #define NAND_MFR_AMD		0x01
442 
443 /**
444  * struct nand_flash_dev - NAND Flash Device ID Structure
445  * @name:	Identify the device type
446  * @id:		device ID code
447  * @pagesize:	Pagesize in bytes. Either 256 or 512 or 0
448  *		If the pagesize is 0, then the real pagesize
449  *		and the eraseize are determined from the
450  *		extended id bytes in the chip
451  * @erasesize:	Size of an erase block in the flash device.
452  * @chipsize:	Total chipsize in Mega Bytes
453  * @options:	Bitfield to store chip relevant options
454  */
455 struct nand_flash_dev {
456 	char *name;
457 	int id;
458 	unsigned long pagesize;
459 	unsigned long chipsize;
460 	unsigned long erasesize;
461 	unsigned long options;
462 };
463 
464 /**
465  * struct nand_manufacturers - NAND Flash Manufacturer ID Structure
466  * @name:	Manufacturer name
467  * @id:		manufacturer ID code of device.
468 */
469 struct nand_manufacturers {
470 	int id;
471 	char * name;
472 };
473 
474 extern const struct nand_flash_dev nand_flash_ids[];
475 extern const struct nand_manufacturers nand_manuf_ids[];
476 
477 extern int nand_scan_bbt(struct mtd_info *mtd, struct nand_bbt_descr *bd);
478 extern int nand_update_bbt(struct mtd_info *mtd, loff_t offs);
479 extern int nand_default_bbt(struct mtd_info *mtd);
480 extern int nand_isbad_bbt(struct mtd_info *mtd, loff_t offs, int allowbbt);
481 extern int nand_erase_nand(struct mtd_info *mtd, struct erase_info *instr,
482 			   int allowbbt);
483 extern int nand_do_read(struct mtd_info *mtd, loff_t from, size_t len,
484 			size_t * retlen, uint8_t * buf);
485 
486 /*
487 * Constants for oob configuration
488 */
489 #define NAND_SMALL_BADBLOCK_POS		5
490 #define NAND_LARGE_BADBLOCK_POS		0
491 
492 /**
493  * struct platform_nand_chip - chip level device structure
494  * @nr_chips:		max. number of chips to scan for
495  * @chip_offset:	chip number offset
496  * @nr_partitions:	number of partitions pointed to by partitions (or zero)
497  * @partitions:		mtd partition list
498  * @chip_delay:		R/B delay value in us
499  * @options:		Option flags, e.g. 16bit buswidth
500  * @ecclayout:		ecc layout info structure
501  * @part_probe_types:	NULL-terminated array of probe types
502  * @priv:		hardware controller specific settings
503  */
504 struct platform_nand_chip {
505 	int			nr_chips;
506 	int			chip_offset;
507 	int			nr_partitions;
508 	struct mtd_partition	*partitions;
509 	struct nand_ecclayout	*ecclayout;
510 	int			chip_delay;
511 	unsigned int		options;
512 	const char		**part_probe_types;
513 	void			*priv;
514 };
515 
516 /**
517  * struct platform_nand_ctrl - controller level device structure
518  * @hwcontrol:		platform specific hardware control structure
519  * @dev_ready:		platform specific function to read ready/busy pin
520  * @select_chip:	platform specific chip select function
521  * @cmd_ctrl:		platform specific function for controlling
522  *			ALE/CLE/nCE. Also used to write command and address
523  * @priv:		private data to transport driver specific settings
524  *
525  * All fields are optional and depend on the hardware driver requirements
526  */
527 struct platform_nand_ctrl {
528 	void		(*hwcontrol)(struct mtd_info *mtd, int cmd);
529 	int		(*dev_ready)(struct mtd_info *mtd);
530 	void		(*select_chip)(struct mtd_info *mtd, int chip);
531 	void		(*cmd_ctrl)(struct mtd_info *mtd, int dat,
532 				    unsigned int ctrl);
533 	void		*priv;
534 };
535 
536 /**
537  * struct platform_nand_data - container structure for platform-specific data
538  * @chip:		chip level chip structure
539  * @ctrl:		controller level device structure
540  */
541 struct platform_nand_data {
542 	struct platform_nand_chip	chip;
543 	struct platform_nand_ctrl	ctrl;
544 };
545 
546 /* Some helpers to access the data structures */
547 static inline
548 struct platform_nand_chip *get_platform_nandchip(struct mtd_info *mtd)
549 {
550 	struct nand_chip *chip = mtd->priv;
551 
552 	return chip->priv;
553 }
554 
555 #endif /* __LINUX_MTD_NAND_H */
556