xref: /openbmc/linux/include/linux/mtd/mtd.h (revision 2359ccdd)
1 /*
2  * Copyright © 1999-2010 David Woodhouse <dwmw2@infradead.org> et al.
3  *
4  * This program is free software; you can redistribute it and/or modify
5  * it under the terms of the GNU General Public License as published by
6  * the Free Software Foundation; either version 2 of the License, or
7  * (at your option) any later version.
8  *
9  * This program is distributed in the hope that it will be useful,
10  * but WITHOUT ANY WARRANTY; without even the implied warranty of
11  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
12  * GNU General Public License for more details.
13  *
14  * You should have received a copy of the GNU General Public License
15  * along with this program; if not, write to the Free Software
16  * Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA  02110-1301  USA
17  *
18  */
19 
20 #ifndef __MTD_MTD_H__
21 #define __MTD_MTD_H__
22 
23 #include <linux/types.h>
24 #include <linux/uio.h>
25 #include <linux/notifier.h>
26 #include <linux/device.h>
27 #include <linux/of.h>
28 
29 #include <mtd/mtd-abi.h>
30 
31 #include <asm/div64.h>
32 
33 #define MTD_FAIL_ADDR_UNKNOWN -1LL
34 
35 struct mtd_info;
36 
37 /*
38  * If the erase fails, fail_addr might indicate exactly which block failed. If
39  * fail_addr = MTD_FAIL_ADDR_UNKNOWN, the failure was not at the device level
40  * or was not specific to any particular block.
41  */
42 struct erase_info {
43 	uint64_t addr;
44 	uint64_t len;
45 	uint64_t fail_addr;
46 };
47 
48 struct mtd_erase_region_info {
49 	uint64_t offset;		/* At which this region starts, from the beginning of the MTD */
50 	uint32_t erasesize;		/* For this region */
51 	uint32_t numblocks;		/* Number of blocks of erasesize in this region */
52 	unsigned long *lockmap;		/* If keeping bitmap of locks */
53 };
54 
55 /**
56  * struct mtd_oob_ops - oob operation operands
57  * @mode:	operation mode
58  *
59  * @len:	number of data bytes to write/read
60  *
61  * @retlen:	number of data bytes written/read
62  *
63  * @ooblen:	number of oob bytes to write/read
64  * @oobretlen:	number of oob bytes written/read
65  * @ooboffs:	offset of oob data in the oob area (only relevant when
66  *		mode = MTD_OPS_PLACE_OOB or MTD_OPS_RAW)
67  * @datbuf:	data buffer - if NULL only oob data are read/written
68  * @oobbuf:	oob data buffer
69  *
70  * Note, it is allowed to read more than one OOB area at one go, but not write.
71  * The interface assumes that the OOB write requests program only one page's
72  * OOB area.
73  */
74 struct mtd_oob_ops {
75 	unsigned int	mode;
76 	size_t		len;
77 	size_t		retlen;
78 	size_t		ooblen;
79 	size_t		oobretlen;
80 	uint32_t	ooboffs;
81 	uint8_t		*datbuf;
82 	uint8_t		*oobbuf;
83 };
84 
85 #define MTD_MAX_OOBFREE_ENTRIES_LARGE	32
86 #define MTD_MAX_ECCPOS_ENTRIES_LARGE	640
87 /**
88  * struct mtd_oob_region - oob region definition
89  * @offset: region offset
90  * @length: region length
91  *
92  * This structure describes a region of the OOB area, and is used
93  * to retrieve ECC or free bytes sections.
94  * Each section is defined by an offset within the OOB area and a
95  * length.
96  */
97 struct mtd_oob_region {
98 	u32 offset;
99 	u32 length;
100 };
101 
102 /*
103  * struct mtd_ooblayout_ops - NAND OOB layout operations
104  * @ecc: function returning an ECC region in the OOB area.
105  *	 Should return -ERANGE if %section exceeds the total number of
106  *	 ECC sections.
107  * @free: function returning a free region in the OOB area.
108  *	  Should return -ERANGE if %section exceeds the total number of
109  *	  free sections.
110  */
111 struct mtd_ooblayout_ops {
112 	int (*ecc)(struct mtd_info *mtd, int section,
113 		   struct mtd_oob_region *oobecc);
114 	int (*free)(struct mtd_info *mtd, int section,
115 		    struct mtd_oob_region *oobfree);
116 };
117 
118 /**
119  * struct mtd_pairing_info - page pairing information
120  *
121  * @pair: pair id
122  * @group: group id
123  *
124  * The term "pair" is used here, even though TLC NANDs might group pages by 3
125  * (3 bits in a single cell). A pair should regroup all pages that are sharing
126  * the same cell. Pairs are then indexed in ascending order.
127  *
128  * @group is defining the position of a page in a given pair. It can also be
129  * seen as the bit position in the cell: page attached to bit 0 belongs to
130  * group 0, page attached to bit 1 belongs to group 1, etc.
131  *
132  * Example:
133  * The H27UCG8T2BTR-BC datasheet describes the following pairing scheme:
134  *
135  *		group-0		group-1
136  *
137  *  pair-0	page-0		page-4
138  *  pair-1	page-1		page-5
139  *  pair-2	page-2		page-8
140  *  ...
141  *  pair-127	page-251	page-255
142  *
143  *
144  * Note that the "group" and "pair" terms were extracted from Samsung and
145  * Hynix datasheets, and might be referenced under other names in other
146  * datasheets (Micron is describing this concept as "shared pages").
147  */
148 struct mtd_pairing_info {
149 	int pair;
150 	int group;
151 };
152 
153 /**
154  * struct mtd_pairing_scheme - page pairing scheme description
155  *
156  * @ngroups: number of groups. Should be related to the number of bits
157  *	     per cell.
158  * @get_info: converts a write-unit (page number within an erase block) into
159  *	      mtd_pairing information (pair + group). This function should
160  *	      fill the info parameter based on the wunit index or return
161  *	      -EINVAL if the wunit parameter is invalid.
162  * @get_wunit: converts pairing information into a write-unit (page) number.
163  *	       This function should return the wunit index pointed by the
164  *	       pairing information described in the info argument. It should
165  *	       return -EINVAL, if there's no wunit corresponding to the
166  *	       passed pairing information.
167  *
168  * See mtd_pairing_info documentation for a detailed explanation of the
169  * pair and group concepts.
170  *
171  * The mtd_pairing_scheme structure provides a generic solution to represent
172  * NAND page pairing scheme. Instead of exposing two big tables to do the
173  * write-unit <-> (pair + group) conversions, we ask the MTD drivers to
174  * implement the ->get_info() and ->get_wunit() functions.
175  *
176  * MTD users will then be able to query these information by using the
177  * mtd_pairing_info_to_wunit() and mtd_wunit_to_pairing_info() helpers.
178  *
179  * @ngroups is here to help MTD users iterating over all the pages in a
180  * given pair. This value can be retrieved by MTD users using the
181  * mtd_pairing_groups() helper.
182  *
183  * Examples are given in the mtd_pairing_info_to_wunit() and
184  * mtd_wunit_to_pairing_info() documentation.
185  */
186 struct mtd_pairing_scheme {
187 	int ngroups;
188 	int (*get_info)(struct mtd_info *mtd, int wunit,
189 			struct mtd_pairing_info *info);
190 	int (*get_wunit)(struct mtd_info *mtd,
191 			 const struct mtd_pairing_info *info);
192 };
193 
194 struct module;	/* only needed for owner field in mtd_info */
195 
196 /**
197  * struct mtd_debug_info - debugging information for an MTD device.
198  *
199  * @dfs_dir: direntry object of the MTD device debugfs directory
200  */
201 struct mtd_debug_info {
202 	struct dentry *dfs_dir;
203 };
204 
205 struct mtd_info {
206 	u_char type;
207 	uint32_t flags;
208 	uint64_t size;	 // Total size of the MTD
209 
210 	/* "Major" erase size for the device. Naïve users may take this
211 	 * to be the only erase size available, or may use the more detailed
212 	 * information below if they desire
213 	 */
214 	uint32_t erasesize;
215 	/* Minimal writable flash unit size. In case of NOR flash it is 1 (even
216 	 * though individual bits can be cleared), in case of NAND flash it is
217 	 * one NAND page (or half, or one-fourths of it), in case of ECC-ed NOR
218 	 * it is of ECC block size, etc. It is illegal to have writesize = 0.
219 	 * Any driver registering a struct mtd_info must ensure a writesize of
220 	 * 1 or larger.
221 	 */
222 	uint32_t writesize;
223 
224 	/*
225 	 * Size of the write buffer used by the MTD. MTD devices having a write
226 	 * buffer can write multiple writesize chunks at a time. E.g. while
227 	 * writing 4 * writesize bytes to a device with 2 * writesize bytes
228 	 * buffer the MTD driver can (but doesn't have to) do 2 writesize
229 	 * operations, but not 4. Currently, all NANDs have writebufsize
230 	 * equivalent to writesize (NAND page size). Some NOR flashes do have
231 	 * writebufsize greater than writesize.
232 	 */
233 	uint32_t writebufsize;
234 
235 	uint32_t oobsize;   // Amount of OOB data per block (e.g. 16)
236 	uint32_t oobavail;  // Available OOB bytes per block
237 
238 	/*
239 	 * If erasesize is a power of 2 then the shift is stored in
240 	 * erasesize_shift otherwise erasesize_shift is zero. Ditto writesize.
241 	 */
242 	unsigned int erasesize_shift;
243 	unsigned int writesize_shift;
244 	/* Masks based on erasesize_shift and writesize_shift */
245 	unsigned int erasesize_mask;
246 	unsigned int writesize_mask;
247 
248 	/*
249 	 * read ops return -EUCLEAN if max number of bitflips corrected on any
250 	 * one region comprising an ecc step equals or exceeds this value.
251 	 * Settable by driver, else defaults to ecc_strength.  User can override
252 	 * in sysfs.  N.B. The meaning of the -EUCLEAN return code has changed;
253 	 * see Documentation/ABI/testing/sysfs-class-mtd for more detail.
254 	 */
255 	unsigned int bitflip_threshold;
256 
257 	/* Kernel-only stuff starts here. */
258 	const char *name;
259 	int index;
260 
261 	/* OOB layout description */
262 	const struct mtd_ooblayout_ops *ooblayout;
263 
264 	/* NAND pairing scheme, only provided for MLC/TLC NANDs */
265 	const struct mtd_pairing_scheme *pairing;
266 
267 	/* the ecc step size. */
268 	unsigned int ecc_step_size;
269 
270 	/* max number of correctible bit errors per ecc step */
271 	unsigned int ecc_strength;
272 
273 	/* Data for variable erase regions. If numeraseregions is zero,
274 	 * it means that the whole device has erasesize as given above.
275 	 */
276 	int numeraseregions;
277 	struct mtd_erase_region_info *eraseregions;
278 
279 	/*
280 	 * Do not call via these pointers, use corresponding mtd_*()
281 	 * wrappers instead.
282 	 */
283 	int (*_erase) (struct mtd_info *mtd, struct erase_info *instr);
284 	int (*_point) (struct mtd_info *mtd, loff_t from, size_t len,
285 		       size_t *retlen, void **virt, resource_size_t *phys);
286 	int (*_unpoint) (struct mtd_info *mtd, loff_t from, size_t len);
287 	int (*_read) (struct mtd_info *mtd, loff_t from, size_t len,
288 		      size_t *retlen, u_char *buf);
289 	int (*_write) (struct mtd_info *mtd, loff_t to, size_t len,
290 		       size_t *retlen, const u_char *buf);
291 	int (*_panic_write) (struct mtd_info *mtd, loff_t to, size_t len,
292 			     size_t *retlen, const u_char *buf);
293 	int (*_read_oob) (struct mtd_info *mtd, loff_t from,
294 			  struct mtd_oob_ops *ops);
295 	int (*_write_oob) (struct mtd_info *mtd, loff_t to,
296 			   struct mtd_oob_ops *ops);
297 	int (*_get_fact_prot_info) (struct mtd_info *mtd, size_t len,
298 				    size_t *retlen, struct otp_info *buf);
299 	int (*_read_fact_prot_reg) (struct mtd_info *mtd, loff_t from,
300 				    size_t len, size_t *retlen, u_char *buf);
301 	int (*_get_user_prot_info) (struct mtd_info *mtd, size_t len,
302 				    size_t *retlen, struct otp_info *buf);
303 	int (*_read_user_prot_reg) (struct mtd_info *mtd, loff_t from,
304 				    size_t len, size_t *retlen, u_char *buf);
305 	int (*_write_user_prot_reg) (struct mtd_info *mtd, loff_t to,
306 				     size_t len, size_t *retlen, u_char *buf);
307 	int (*_lock_user_prot_reg) (struct mtd_info *mtd, loff_t from,
308 				    size_t len);
309 	int (*_writev) (struct mtd_info *mtd, const struct kvec *vecs,
310 			unsigned long count, loff_t to, size_t *retlen);
311 	void (*_sync) (struct mtd_info *mtd);
312 	int (*_lock) (struct mtd_info *mtd, loff_t ofs, uint64_t len);
313 	int (*_unlock) (struct mtd_info *mtd, loff_t ofs, uint64_t len);
314 	int (*_is_locked) (struct mtd_info *mtd, loff_t ofs, uint64_t len);
315 	int (*_block_isreserved) (struct mtd_info *mtd, loff_t ofs);
316 	int (*_block_isbad) (struct mtd_info *mtd, loff_t ofs);
317 	int (*_block_markbad) (struct mtd_info *mtd, loff_t ofs);
318 	int (*_max_bad_blocks) (struct mtd_info *mtd, loff_t ofs, size_t len);
319 	int (*_suspend) (struct mtd_info *mtd);
320 	void (*_resume) (struct mtd_info *mtd);
321 	void (*_reboot) (struct mtd_info *mtd);
322 	/*
323 	 * If the driver is something smart, like UBI, it may need to maintain
324 	 * its own reference counting. The below functions are only for driver.
325 	 */
326 	int (*_get_device) (struct mtd_info *mtd);
327 	void (*_put_device) (struct mtd_info *mtd);
328 
329 	struct notifier_block reboot_notifier;  /* default mode before reboot */
330 
331 	/* ECC status information */
332 	struct mtd_ecc_stats ecc_stats;
333 	/* Subpage shift (NAND) */
334 	int subpage_sft;
335 
336 	void *priv;
337 
338 	struct module *owner;
339 	struct device dev;
340 	int usecount;
341 	struct mtd_debug_info dbg;
342 };
343 
344 int mtd_ooblayout_ecc(struct mtd_info *mtd, int section,
345 		      struct mtd_oob_region *oobecc);
346 int mtd_ooblayout_find_eccregion(struct mtd_info *mtd, int eccbyte,
347 				 int *section,
348 				 struct mtd_oob_region *oobregion);
349 int mtd_ooblayout_get_eccbytes(struct mtd_info *mtd, u8 *eccbuf,
350 			       const u8 *oobbuf, int start, int nbytes);
351 int mtd_ooblayout_set_eccbytes(struct mtd_info *mtd, const u8 *eccbuf,
352 			       u8 *oobbuf, int start, int nbytes);
353 int mtd_ooblayout_free(struct mtd_info *mtd, int section,
354 		       struct mtd_oob_region *oobfree);
355 int mtd_ooblayout_get_databytes(struct mtd_info *mtd, u8 *databuf,
356 				const u8 *oobbuf, int start, int nbytes);
357 int mtd_ooblayout_set_databytes(struct mtd_info *mtd, const u8 *databuf,
358 				u8 *oobbuf, int start, int nbytes);
359 int mtd_ooblayout_count_freebytes(struct mtd_info *mtd);
360 int mtd_ooblayout_count_eccbytes(struct mtd_info *mtd);
361 
362 static inline void mtd_set_ooblayout(struct mtd_info *mtd,
363 				     const struct mtd_ooblayout_ops *ooblayout)
364 {
365 	mtd->ooblayout = ooblayout;
366 }
367 
368 static inline void mtd_set_pairing_scheme(struct mtd_info *mtd,
369 				const struct mtd_pairing_scheme *pairing)
370 {
371 	mtd->pairing = pairing;
372 }
373 
374 static inline void mtd_set_of_node(struct mtd_info *mtd,
375 				   struct device_node *np)
376 {
377 	mtd->dev.of_node = np;
378 	if (!mtd->name)
379 		of_property_read_string(np, "label", &mtd->name);
380 }
381 
382 static inline struct device_node *mtd_get_of_node(struct mtd_info *mtd)
383 {
384 	return dev_of_node(&mtd->dev);
385 }
386 
387 static inline int mtd_oobavail(struct mtd_info *mtd, struct mtd_oob_ops *ops)
388 {
389 	return ops->mode == MTD_OPS_AUTO_OOB ? mtd->oobavail : mtd->oobsize;
390 }
391 
392 static inline int mtd_max_bad_blocks(struct mtd_info *mtd,
393 				     loff_t ofs, size_t len)
394 {
395 	if (!mtd->_max_bad_blocks)
396 		return -ENOTSUPP;
397 
398 	if (mtd->size < (len + ofs) || ofs < 0)
399 		return -EINVAL;
400 
401 	return mtd->_max_bad_blocks(mtd, ofs, len);
402 }
403 
404 int mtd_wunit_to_pairing_info(struct mtd_info *mtd, int wunit,
405 			      struct mtd_pairing_info *info);
406 int mtd_pairing_info_to_wunit(struct mtd_info *mtd,
407 			      const struct mtd_pairing_info *info);
408 int mtd_pairing_groups(struct mtd_info *mtd);
409 int mtd_erase(struct mtd_info *mtd, struct erase_info *instr);
410 int mtd_point(struct mtd_info *mtd, loff_t from, size_t len, size_t *retlen,
411 	      void **virt, resource_size_t *phys);
412 int mtd_unpoint(struct mtd_info *mtd, loff_t from, size_t len);
413 unsigned long mtd_get_unmapped_area(struct mtd_info *mtd, unsigned long len,
414 				    unsigned long offset, unsigned long flags);
415 int mtd_read(struct mtd_info *mtd, loff_t from, size_t len, size_t *retlen,
416 	     u_char *buf);
417 int mtd_write(struct mtd_info *mtd, loff_t to, size_t len, size_t *retlen,
418 	      const u_char *buf);
419 int mtd_panic_write(struct mtd_info *mtd, loff_t to, size_t len, size_t *retlen,
420 		    const u_char *buf);
421 
422 int mtd_read_oob(struct mtd_info *mtd, loff_t from, struct mtd_oob_ops *ops);
423 int mtd_write_oob(struct mtd_info *mtd, loff_t to, struct mtd_oob_ops *ops);
424 
425 int mtd_get_fact_prot_info(struct mtd_info *mtd, size_t len, size_t *retlen,
426 			   struct otp_info *buf);
427 int mtd_read_fact_prot_reg(struct mtd_info *mtd, loff_t from, size_t len,
428 			   size_t *retlen, u_char *buf);
429 int mtd_get_user_prot_info(struct mtd_info *mtd, size_t len, size_t *retlen,
430 			   struct otp_info *buf);
431 int mtd_read_user_prot_reg(struct mtd_info *mtd, loff_t from, size_t len,
432 			   size_t *retlen, u_char *buf);
433 int mtd_write_user_prot_reg(struct mtd_info *mtd, loff_t to, size_t len,
434 			    size_t *retlen, u_char *buf);
435 int mtd_lock_user_prot_reg(struct mtd_info *mtd, loff_t from, size_t len);
436 
437 int mtd_writev(struct mtd_info *mtd, const struct kvec *vecs,
438 	       unsigned long count, loff_t to, size_t *retlen);
439 
440 static inline void mtd_sync(struct mtd_info *mtd)
441 {
442 	if (mtd->_sync)
443 		mtd->_sync(mtd);
444 }
445 
446 int mtd_lock(struct mtd_info *mtd, loff_t ofs, uint64_t len);
447 int mtd_unlock(struct mtd_info *mtd, loff_t ofs, uint64_t len);
448 int mtd_is_locked(struct mtd_info *mtd, loff_t ofs, uint64_t len);
449 int mtd_block_isreserved(struct mtd_info *mtd, loff_t ofs);
450 int mtd_block_isbad(struct mtd_info *mtd, loff_t ofs);
451 int mtd_block_markbad(struct mtd_info *mtd, loff_t ofs);
452 
453 static inline int mtd_suspend(struct mtd_info *mtd)
454 {
455 	return mtd->_suspend ? mtd->_suspend(mtd) : 0;
456 }
457 
458 static inline void mtd_resume(struct mtd_info *mtd)
459 {
460 	if (mtd->_resume)
461 		mtd->_resume(mtd);
462 }
463 
464 static inline uint32_t mtd_div_by_eb(uint64_t sz, struct mtd_info *mtd)
465 {
466 	if (mtd->erasesize_shift)
467 		return sz >> mtd->erasesize_shift;
468 	do_div(sz, mtd->erasesize);
469 	return sz;
470 }
471 
472 static inline uint32_t mtd_mod_by_eb(uint64_t sz, struct mtd_info *mtd)
473 {
474 	if (mtd->erasesize_shift)
475 		return sz & mtd->erasesize_mask;
476 	return do_div(sz, mtd->erasesize);
477 }
478 
479 /**
480  * mtd_align_erase_req - Adjust an erase request to align things on eraseblock
481  *			 boundaries.
482  * @mtd: the MTD device this erase request applies on
483  * @req: the erase request to adjust
484  *
485  * This function will adjust @req->addr and @req->len to align them on
486  * @mtd->erasesize. Of course we expect @mtd->erasesize to be != 0.
487  */
488 static inline void mtd_align_erase_req(struct mtd_info *mtd,
489 				       struct erase_info *req)
490 {
491 	u32 mod;
492 
493 	if (WARN_ON(!mtd->erasesize))
494 		return;
495 
496 	mod = mtd_mod_by_eb(req->addr, mtd);
497 	if (mod) {
498 		req->addr -= mod;
499 		req->len += mod;
500 	}
501 
502 	mod = mtd_mod_by_eb(req->addr + req->len, mtd);
503 	if (mod)
504 		req->len += mtd->erasesize - mod;
505 }
506 
507 static inline uint32_t mtd_div_by_ws(uint64_t sz, struct mtd_info *mtd)
508 {
509 	if (mtd->writesize_shift)
510 		return sz >> mtd->writesize_shift;
511 	do_div(sz, mtd->writesize);
512 	return sz;
513 }
514 
515 static inline uint32_t mtd_mod_by_ws(uint64_t sz, struct mtd_info *mtd)
516 {
517 	if (mtd->writesize_shift)
518 		return sz & mtd->writesize_mask;
519 	return do_div(sz, mtd->writesize);
520 }
521 
522 static inline int mtd_wunit_per_eb(struct mtd_info *mtd)
523 {
524 	return mtd->erasesize / mtd->writesize;
525 }
526 
527 static inline int mtd_offset_to_wunit(struct mtd_info *mtd, loff_t offs)
528 {
529 	return mtd_div_by_ws(mtd_mod_by_eb(offs, mtd), mtd);
530 }
531 
532 static inline loff_t mtd_wunit_to_offset(struct mtd_info *mtd, loff_t base,
533 					 int wunit)
534 {
535 	return base + (wunit * mtd->writesize);
536 }
537 
538 
539 static inline int mtd_has_oob(const struct mtd_info *mtd)
540 {
541 	return mtd->_read_oob && mtd->_write_oob;
542 }
543 
544 static inline int mtd_type_is_nand(const struct mtd_info *mtd)
545 {
546 	return mtd->type == MTD_NANDFLASH || mtd->type == MTD_MLCNANDFLASH;
547 }
548 
549 static inline int mtd_can_have_bb(const struct mtd_info *mtd)
550 {
551 	return !!mtd->_block_isbad;
552 }
553 
554 	/* Kernel-side ioctl definitions */
555 
556 struct mtd_partition;
557 struct mtd_part_parser_data;
558 
559 extern int mtd_device_parse_register(struct mtd_info *mtd,
560 				     const char * const *part_probe_types,
561 				     struct mtd_part_parser_data *parser_data,
562 				     const struct mtd_partition *defparts,
563 				     int defnr_parts);
564 #define mtd_device_register(master, parts, nr_parts)	\
565 	mtd_device_parse_register(master, NULL, NULL, parts, nr_parts)
566 extern int mtd_device_unregister(struct mtd_info *master);
567 extern struct mtd_info *get_mtd_device(struct mtd_info *mtd, int num);
568 extern int __get_mtd_device(struct mtd_info *mtd);
569 extern void __put_mtd_device(struct mtd_info *mtd);
570 extern struct mtd_info *get_mtd_device_nm(const char *name);
571 extern void put_mtd_device(struct mtd_info *mtd);
572 
573 
574 struct mtd_notifier {
575 	void (*add)(struct mtd_info *mtd);
576 	void (*remove)(struct mtd_info *mtd);
577 	struct list_head list;
578 };
579 
580 
581 extern void register_mtd_user (struct mtd_notifier *new);
582 extern int unregister_mtd_user (struct mtd_notifier *old);
583 void *mtd_kmalloc_up_to(const struct mtd_info *mtd, size_t *size);
584 
585 static inline int mtd_is_bitflip(int err) {
586 	return err == -EUCLEAN;
587 }
588 
589 static inline int mtd_is_eccerr(int err) {
590 	return err == -EBADMSG;
591 }
592 
593 static inline int mtd_is_bitflip_or_eccerr(int err) {
594 	return mtd_is_bitflip(err) || mtd_is_eccerr(err);
595 }
596 
597 unsigned mtd_mmap_capabilities(struct mtd_info *mtd);
598 
599 #endif /* __MTD_MTD_H__ */
600