1 /* SPDX-License-Identifier: GPL-2.0-or-later */
2 /*
3 * Copyright © 1999-2010 David Woodhouse <dwmw2@infradead.org> et al.
4 */
5
6 #ifndef __MTD_MTD_H__
7 #define __MTD_MTD_H__
8
9 #include <linux/types.h>
10 #include <linux/uio.h>
11 #include <linux/notifier.h>
12 #include <linux/device.h>
13 #include <linux/of.h>
14 #include <linux/nvmem-provider.h>
15
16 #include <mtd/mtd-abi.h>
17
18 #include <asm/div64.h>
19
20 #define MTD_FAIL_ADDR_UNKNOWN -1LL
21
22 struct mtd_info;
23
24 /*
25 * If the erase fails, fail_addr might indicate exactly which block failed. If
26 * fail_addr = MTD_FAIL_ADDR_UNKNOWN, the failure was not at the device level
27 * or was not specific to any particular block.
28 */
29 struct erase_info {
30 uint64_t addr;
31 uint64_t len;
32 uint64_t fail_addr;
33 };
34
35 struct mtd_erase_region_info {
36 uint64_t offset; /* At which this region starts, from the beginning of the MTD */
37 uint32_t erasesize; /* For this region */
38 uint32_t numblocks; /* Number of blocks of erasesize in this region */
39 unsigned long *lockmap; /* If keeping bitmap of locks */
40 };
41
42 /**
43 * struct mtd_oob_ops - oob operation operands
44 * @mode: operation mode
45 *
46 * @len: number of data bytes to write/read
47 *
48 * @retlen: number of data bytes written/read
49 *
50 * @ooblen: number of oob bytes to write/read
51 * @oobretlen: number of oob bytes written/read
52 * @ooboffs: offset of oob data in the oob area (only relevant when
53 * mode = MTD_OPS_PLACE_OOB or MTD_OPS_RAW)
54 * @datbuf: data buffer - if NULL only oob data are read/written
55 * @oobbuf: oob data buffer
56 *
57 * Note, some MTD drivers do not allow you to write more than one OOB area at
58 * one go. If you try to do that on such an MTD device, -EINVAL will be
59 * returned. If you want to make your implementation portable on all kind of MTD
60 * devices you should split the write request into several sub-requests when the
61 * request crosses a page boundary.
62 */
63 struct mtd_oob_ops {
64 unsigned int mode;
65 size_t len;
66 size_t retlen;
67 size_t ooblen;
68 size_t oobretlen;
69 uint32_t ooboffs;
70 uint8_t *datbuf;
71 uint8_t *oobbuf;
72 };
73
74 #define MTD_MAX_OOBFREE_ENTRIES_LARGE 32
75 #define MTD_MAX_ECCPOS_ENTRIES_LARGE 640
76 /**
77 * struct mtd_oob_region - oob region definition
78 * @offset: region offset
79 * @length: region length
80 *
81 * This structure describes a region of the OOB area, and is used
82 * to retrieve ECC or free bytes sections.
83 * Each section is defined by an offset within the OOB area and a
84 * length.
85 */
86 struct mtd_oob_region {
87 u32 offset;
88 u32 length;
89 };
90
91 /*
92 * struct mtd_ooblayout_ops - NAND OOB layout operations
93 * @ecc: function returning an ECC region in the OOB area.
94 * Should return -ERANGE if %section exceeds the total number of
95 * ECC sections.
96 * @free: function returning a free region in the OOB area.
97 * Should return -ERANGE if %section exceeds the total number of
98 * free sections.
99 */
100 struct mtd_ooblayout_ops {
101 int (*ecc)(struct mtd_info *mtd, int section,
102 struct mtd_oob_region *oobecc);
103 int (*free)(struct mtd_info *mtd, int section,
104 struct mtd_oob_region *oobfree);
105 };
106
107 /**
108 * struct mtd_pairing_info - page pairing information
109 *
110 * @pair: pair id
111 * @group: group id
112 *
113 * The term "pair" is used here, even though TLC NANDs might group pages by 3
114 * (3 bits in a single cell). A pair should regroup all pages that are sharing
115 * the same cell. Pairs are then indexed in ascending order.
116 *
117 * @group is defining the position of a page in a given pair. It can also be
118 * seen as the bit position in the cell: page attached to bit 0 belongs to
119 * group 0, page attached to bit 1 belongs to group 1, etc.
120 *
121 * Example:
122 * The H27UCG8T2BTR-BC datasheet describes the following pairing scheme:
123 *
124 * group-0 group-1
125 *
126 * pair-0 page-0 page-4
127 * pair-1 page-1 page-5
128 * pair-2 page-2 page-8
129 * ...
130 * pair-127 page-251 page-255
131 *
132 *
133 * Note that the "group" and "pair" terms were extracted from Samsung and
134 * Hynix datasheets, and might be referenced under other names in other
135 * datasheets (Micron is describing this concept as "shared pages").
136 */
137 struct mtd_pairing_info {
138 int pair;
139 int group;
140 };
141
142 /**
143 * struct mtd_pairing_scheme - page pairing scheme description
144 *
145 * @ngroups: number of groups. Should be related to the number of bits
146 * per cell.
147 * @get_info: converts a write-unit (page number within an erase block) into
148 * mtd_pairing information (pair + group). This function should
149 * fill the info parameter based on the wunit index or return
150 * -EINVAL if the wunit parameter is invalid.
151 * @get_wunit: converts pairing information into a write-unit (page) number.
152 * This function should return the wunit index pointed by the
153 * pairing information described in the info argument. It should
154 * return -EINVAL, if there's no wunit corresponding to the
155 * passed pairing information.
156 *
157 * See mtd_pairing_info documentation for a detailed explanation of the
158 * pair and group concepts.
159 *
160 * The mtd_pairing_scheme structure provides a generic solution to represent
161 * NAND page pairing scheme. Instead of exposing two big tables to do the
162 * write-unit <-> (pair + group) conversions, we ask the MTD drivers to
163 * implement the ->get_info() and ->get_wunit() functions.
164 *
165 * MTD users will then be able to query these information by using the
166 * mtd_pairing_info_to_wunit() and mtd_wunit_to_pairing_info() helpers.
167 *
168 * @ngroups is here to help MTD users iterating over all the pages in a
169 * given pair. This value can be retrieved by MTD users using the
170 * mtd_pairing_groups() helper.
171 *
172 * Examples are given in the mtd_pairing_info_to_wunit() and
173 * mtd_wunit_to_pairing_info() documentation.
174 */
175 struct mtd_pairing_scheme {
176 int ngroups;
177 int (*get_info)(struct mtd_info *mtd, int wunit,
178 struct mtd_pairing_info *info);
179 int (*get_wunit)(struct mtd_info *mtd,
180 const struct mtd_pairing_info *info);
181 };
182
183 struct module; /* only needed for owner field in mtd_info */
184
185 /**
186 * struct mtd_debug_info - debugging information for an MTD device.
187 *
188 * @dfs_dir: direntry object of the MTD device debugfs directory
189 */
190 struct mtd_debug_info {
191 struct dentry *dfs_dir;
192
193 const char *partname;
194 const char *partid;
195 };
196
197 struct mtd_info {
198 u_char type;
199 uint32_t flags;
200 uint32_t orig_flags; /* Flags as before running mtd checks */
201 uint64_t size; // Total size of the MTD
202
203 /* "Major" erase size for the device. Naïve users may take this
204 * to be the only erase size available, or may use the more detailed
205 * information below if they desire
206 */
207 uint32_t erasesize;
208 /* Minimal writable flash unit size. In case of NOR flash it is 1 (even
209 * though individual bits can be cleared), in case of NAND flash it is
210 * one NAND page (or half, or one-fourths of it), in case of ECC-ed NOR
211 * it is of ECC block size, etc. It is illegal to have writesize = 0.
212 * Any driver registering a struct mtd_info must ensure a writesize of
213 * 1 or larger.
214 */
215 uint32_t writesize;
216
217 /*
218 * Size of the write buffer used by the MTD. MTD devices having a write
219 * buffer can write multiple writesize chunks at a time. E.g. while
220 * writing 4 * writesize bytes to a device with 2 * writesize bytes
221 * buffer the MTD driver can (but doesn't have to) do 2 writesize
222 * operations, but not 4. Currently, all NANDs have writebufsize
223 * equivalent to writesize (NAND page size). Some NOR flashes do have
224 * writebufsize greater than writesize.
225 */
226 uint32_t writebufsize;
227
228 uint32_t oobsize; // Amount of OOB data per block (e.g. 16)
229 uint32_t oobavail; // Available OOB bytes per block
230
231 /*
232 * If erasesize is a power of 2 then the shift is stored in
233 * erasesize_shift otherwise erasesize_shift is zero. Ditto writesize.
234 */
235 unsigned int erasesize_shift;
236 unsigned int writesize_shift;
237 /* Masks based on erasesize_shift and writesize_shift */
238 unsigned int erasesize_mask;
239 unsigned int writesize_mask;
240
241 /*
242 * read ops return -EUCLEAN if max number of bitflips corrected on any
243 * one region comprising an ecc step equals or exceeds this value.
244 * Settable by driver, else defaults to ecc_strength. User can override
245 * in sysfs. N.B. The meaning of the -EUCLEAN return code has changed;
246 * see Documentation/ABI/testing/sysfs-class-mtd for more detail.
247 */
248 unsigned int bitflip_threshold;
249
250 /* Kernel-only stuff starts here. */
251 const char *name;
252 int index;
253
254 /* OOB layout description */
255 const struct mtd_ooblayout_ops *ooblayout;
256
257 /* NAND pairing scheme, only provided for MLC/TLC NANDs */
258 const struct mtd_pairing_scheme *pairing;
259
260 /* the ecc step size. */
261 unsigned int ecc_step_size;
262
263 /* max number of correctible bit errors per ecc step */
264 unsigned int ecc_strength;
265
266 /* Data for variable erase regions. If numeraseregions is zero,
267 * it means that the whole device has erasesize as given above.
268 */
269 int numeraseregions;
270 struct mtd_erase_region_info *eraseregions;
271
272 /*
273 * Do not call via these pointers, use corresponding mtd_*()
274 * wrappers instead.
275 */
276 int (*_erase) (struct mtd_info *mtd, struct erase_info *instr);
277 int (*_point) (struct mtd_info *mtd, loff_t from, size_t len,
278 size_t *retlen, void **virt, resource_size_t *phys);
279 int (*_unpoint) (struct mtd_info *mtd, loff_t from, size_t len);
280 int (*_read) (struct mtd_info *mtd, loff_t from, size_t len,
281 size_t *retlen, u_char *buf);
282 int (*_write) (struct mtd_info *mtd, loff_t to, size_t len,
283 size_t *retlen, const u_char *buf);
284 int (*_panic_write) (struct mtd_info *mtd, loff_t to, size_t len,
285 size_t *retlen, const u_char *buf);
286 int (*_read_oob) (struct mtd_info *mtd, loff_t from,
287 struct mtd_oob_ops *ops);
288 int (*_write_oob) (struct mtd_info *mtd, loff_t to,
289 struct mtd_oob_ops *ops);
290 int (*_get_fact_prot_info) (struct mtd_info *mtd, size_t len,
291 size_t *retlen, struct otp_info *buf);
292 int (*_read_fact_prot_reg) (struct mtd_info *mtd, loff_t from,
293 size_t len, size_t *retlen, u_char *buf);
294 int (*_get_user_prot_info) (struct mtd_info *mtd, size_t len,
295 size_t *retlen, struct otp_info *buf);
296 int (*_read_user_prot_reg) (struct mtd_info *mtd, loff_t from,
297 size_t len, size_t *retlen, u_char *buf);
298 int (*_write_user_prot_reg) (struct mtd_info *mtd, loff_t to,
299 size_t len, size_t *retlen, u_char *buf);
300 int (*_lock_user_prot_reg) (struct mtd_info *mtd, loff_t from,
301 size_t len);
302 int (*_writev) (struct mtd_info *mtd, const struct kvec *vecs,
303 unsigned long count, loff_t to, size_t *retlen);
304 void (*_sync) (struct mtd_info *mtd);
305 int (*_lock) (struct mtd_info *mtd, loff_t ofs, uint64_t len);
306 int (*_unlock) (struct mtd_info *mtd, loff_t ofs, uint64_t len);
307 int (*_is_locked) (struct mtd_info *mtd, loff_t ofs, uint64_t len);
308 int (*_block_isreserved) (struct mtd_info *mtd, loff_t ofs);
309 int (*_block_isbad) (struct mtd_info *mtd, loff_t ofs);
310 int (*_block_markbad) (struct mtd_info *mtd, loff_t ofs);
311 int (*_max_bad_blocks) (struct mtd_info *mtd, loff_t ofs, size_t len);
312 int (*_suspend) (struct mtd_info *mtd);
313 void (*_resume) (struct mtd_info *mtd);
314 void (*_reboot) (struct mtd_info *mtd);
315 /*
316 * If the driver is something smart, like UBI, it may need to maintain
317 * its own reference counting. The below functions are only for driver.
318 */
319 int (*_get_device) (struct mtd_info *mtd);
320 void (*_put_device) (struct mtd_info *mtd);
321
322 /*
323 * flag indicates a panic write, low level drivers can take appropriate
324 * action if required to ensure writes go through
325 */
326 bool oops_panic_write;
327
328 struct notifier_block reboot_notifier; /* default mode before reboot */
329
330 /* ECC status information */
331 struct mtd_ecc_stats ecc_stats;
332 /* Subpage shift (NAND) */
333 int subpage_sft;
334
335 void *priv;
336
337 struct module *owner;
338 struct device dev;
339 int usecount;
340 struct mtd_debug_info dbg;
341 struct nvmem_device *nvmem;
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
mtd_set_ooblayout(struct mtd_info * mtd,const struct mtd_ooblayout_ops * ooblayout)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
mtd_set_pairing_scheme(struct mtd_info * mtd,const struct mtd_pairing_scheme * pairing)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
mtd_set_of_node(struct mtd_info * mtd,struct device_node * np)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
mtd_get_of_node(struct mtd_info * mtd)382 static inline struct device_node *mtd_get_of_node(struct mtd_info *mtd)
383 {
384 return dev_of_node(&mtd->dev);
385 }
386
mtd_oobavail(struct mtd_info * mtd,struct mtd_oob_ops * ops)387 static inline u32 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
mtd_max_bad_blocks(struct mtd_info * mtd,loff_t ofs,size_t len)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
mtd_sync(struct mtd_info * mtd)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
mtd_suspend(struct mtd_info * mtd)453 static inline int mtd_suspend(struct mtd_info *mtd)
454 {
455 return mtd->_suspend ? mtd->_suspend(mtd) : 0;
456 }
457
mtd_resume(struct mtd_info * mtd)458 static inline void mtd_resume(struct mtd_info *mtd)
459 {
460 if (mtd->_resume)
461 mtd->_resume(mtd);
462 }
463
mtd_div_by_eb(uint64_t sz,struct mtd_info * mtd)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
mtd_mod_by_eb(uint64_t sz,struct mtd_info * mtd)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 */
mtd_align_erase_req(struct mtd_info * mtd,struct erase_info * req)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
mtd_div_by_ws(uint64_t sz,struct mtd_info * mtd)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
mtd_mod_by_ws(uint64_t sz,struct mtd_info * mtd)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
mtd_wunit_per_eb(struct mtd_info * mtd)522 static inline int mtd_wunit_per_eb(struct mtd_info *mtd)
523 {
524 return mtd->erasesize / mtd->writesize;
525 }
526
mtd_offset_to_wunit(struct mtd_info * mtd,loff_t offs)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
mtd_wunit_to_offset(struct mtd_info * mtd,loff_t base,int wunit)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
mtd_has_oob(const struct mtd_info * mtd)539 static inline int mtd_has_oob(const struct mtd_info *mtd)
540 {
541 return mtd->_read_oob && mtd->_write_oob;
542 }
543
mtd_type_is_nand(const struct mtd_info * mtd)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
mtd_can_have_bb(const struct mtd_info * mtd)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
mtd_is_bitflip(int err)585 static inline int mtd_is_bitflip(int err) {
586 return err == -EUCLEAN;
587 }
588
mtd_is_eccerr(int err)589 static inline int mtd_is_eccerr(int err) {
590 return err == -EBADMSG;
591 }
592
mtd_is_bitflip_or_eccerr(int err)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
