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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/list.h>12#include <linux/notifier.h>13#include <linux/device.h>14#include <linux/of.h>15#include <linux/nvmem-provider.h>16 17#include <mtd/mtd-abi.h>18 19#include <asm/div64.h>20 21#define MTD_FAIL_ADDR_UNKNOWN -1LL22 23struct mtd_info;24 25/*26 * If the erase fails, fail_addr might indicate exactly which block failed. If27 * fail_addr = MTD_FAIL_ADDR_UNKNOWN, the failure was not at the device level28 * or was not specific to any particular block.29 */30struct erase_info {31 uint64_t addr;32 uint64_t len;33 uint64_t fail_addr;34};35 36struct mtd_erase_region_info {37 uint64_t offset; /* At which this region starts, from the beginning of the MTD */38 uint32_t erasesize; /* For this region */39 uint32_t numblocks; /* Number of blocks of erasesize in this region */40 unsigned long *lockmap; /* If keeping bitmap of locks */41};42 43struct mtd_req_stats {44 unsigned int uncorrectable_errors;45 unsigned int corrected_bitflips;46 unsigned int max_bitflips;47};48 49/**50 * struct mtd_oob_ops - oob operation operands51 * @mode: operation mode52 *53 * @len: number of data bytes to write/read54 *55 * @retlen: number of data bytes written/read56 *57 * @ooblen: number of oob bytes to write/read58 * @oobretlen: number of oob bytes written/read59 * @ooboffs: offset of oob data in the oob area (only relevant when60 * mode = MTD_OPS_PLACE_OOB or MTD_OPS_RAW)61 * @datbuf: data buffer - if NULL only oob data are read/written62 * @oobbuf: oob data buffer63 *64 * Note, some MTD drivers do not allow you to write more than one OOB area at65 * one go. If you try to do that on such an MTD device, -EINVAL will be66 * returned. If you want to make your implementation portable on all kind of MTD67 * devices you should split the write request into several sub-requests when the68 * request crosses a page boundary.69 */70struct mtd_oob_ops {71 unsigned int mode;72 size_t len;73 size_t retlen;74 size_t ooblen;75 size_t oobretlen;76 uint32_t ooboffs;77 uint8_t *datbuf;78 uint8_t *oobbuf;79 struct mtd_req_stats *stats;80};81 82/**83 * struct mtd_oob_region - oob region definition84 * @offset: region offset85 * @length: region length86 *87 * This structure describes a region of the OOB area, and is used88 * to retrieve ECC or free bytes sections.89 * Each section is defined by an offset within the OOB area and a90 * length.91 */92struct mtd_oob_region {93 u32 offset;94 u32 length;95};96 97/*98 * struct mtd_ooblayout_ops - NAND OOB layout operations99 * @ecc: function returning an ECC region in the OOB area.100 * Should return -ERANGE if %section exceeds the total number of101 * ECC sections.102 * @free: function returning a free region in the OOB area.103 * Should return -ERANGE if %section exceeds the total number of104 * free sections.105 */106struct mtd_ooblayout_ops {107 int (*ecc)(struct mtd_info *mtd, int section,108 struct mtd_oob_region *oobecc);109 int (*free)(struct mtd_info *mtd, int section,110 struct mtd_oob_region *oobfree);111};112 113/**114 * struct mtd_pairing_info - page pairing information115 *116 * @pair: pair id117 * @group: group id118 *119 * The term "pair" is used here, even though TLC NANDs might group pages by 3120 * (3 bits in a single cell). A pair should regroup all pages that are sharing121 * the same cell. Pairs are then indexed in ascending order.122 *123 * @group is defining the position of a page in a given pair. It can also be124 * seen as the bit position in the cell: page attached to bit 0 belongs to125 * group 0, page attached to bit 1 belongs to group 1, etc.126 *127 * Example:128 * The H27UCG8T2BTR-BC datasheet describes the following pairing scheme:129 *130 * group-0 group-1131 *132 * pair-0 page-0 page-4133 * pair-1 page-1 page-5134 * pair-2 page-2 page-8135 * ...136 * pair-127 page-251 page-255137 *138 *139 * Note that the "group" and "pair" terms were extracted from Samsung and140 * Hynix datasheets, and might be referenced under other names in other141 * datasheets (Micron is describing this concept as "shared pages").142 */143struct mtd_pairing_info {144 int pair;145 int group;146};147 148/**149 * struct mtd_pairing_scheme - page pairing scheme description150 *151 * @ngroups: number of groups. Should be related to the number of bits152 * per cell.153 * @get_info: converts a write-unit (page number within an erase block) into154 * mtd_pairing information (pair + group). This function should155 * fill the info parameter based on the wunit index or return156 * -EINVAL if the wunit parameter is invalid.157 * @get_wunit: converts pairing information into a write-unit (page) number.158 * This function should return the wunit index pointed by the159 * pairing information described in the info argument. It should160 * return -EINVAL, if there's no wunit corresponding to the161 * passed pairing information.162 *163 * See mtd_pairing_info documentation for a detailed explanation of the164 * pair and group concepts.165 *166 * The mtd_pairing_scheme structure provides a generic solution to represent167 * NAND page pairing scheme. Instead of exposing two big tables to do the168 * write-unit <-> (pair + group) conversions, we ask the MTD drivers to169 * implement the ->get_info() and ->get_wunit() functions.170 *171 * MTD users will then be able to query these information by using the172 * mtd_pairing_info_to_wunit() and mtd_wunit_to_pairing_info() helpers.173 *174 * @ngroups is here to help MTD users iterating over all the pages in a175 * given pair. This value can be retrieved by MTD users using the176 * mtd_pairing_groups() helper.177 *178 * Examples are given in the mtd_pairing_info_to_wunit() and179 * mtd_wunit_to_pairing_info() documentation.180 */181struct mtd_pairing_scheme {182 int ngroups;183 int (*get_info)(struct mtd_info *mtd, int wunit,184 struct mtd_pairing_info *info);185 int (*get_wunit)(struct mtd_info *mtd,186 const struct mtd_pairing_info *info);187};188 189struct module; /* only needed for owner field in mtd_info */190 191/**192 * struct mtd_debug_info - debugging information for an MTD device.193 *194 * @dfs_dir: direntry object of the MTD device debugfs directory195 */196struct mtd_debug_info {197 struct dentry *dfs_dir;198};199 200/**201 * struct mtd_part - MTD partition specific fields202 *203 * @node: list node used to add an MTD partition to the parent partition list204 * @offset: offset of the partition relatively to the parent offset205 * @size: partition size. Should be equal to mtd->size unless206 * MTD_SLC_ON_MLC_EMULATION is set207 * @flags: original flags (before the mtdpart logic decided to tweak them based208 * on flash constraints, like eraseblock/pagesize alignment)209 *210 * This struct is embedded in mtd_info and contains partition-specific211 * properties/fields.212 */213struct mtd_part {214 struct list_head node;215 u64 offset;216 u64 size;217 u32 flags;218};219 220/**221 * struct mtd_master - MTD master specific fields222 *223 * @partitions_lock: lock protecting accesses to the partition list. Protects224 * not only the master partition list, but also all225 * sub-partitions.226 * @suspended: set to 1 when the device is suspended, 0 otherwise227 *228 * This struct is embedded in mtd_info and contains master-specific229 * properties/fields. The master is the root MTD device from the MTD partition230 * point of view.231 */232struct mtd_master {233 struct mutex partitions_lock;234 struct mutex chrdev_lock;235 unsigned int suspended : 1;236};237 238struct mtd_info {239 u_char type;240 uint32_t flags;241 uint64_t size; // Total size of the MTD242 243 /* "Major" erase size for the device. Naïve users may take this244 * to be the only erase size available, or may use the more detailed245 * information below if they desire246 */247 uint32_t erasesize;248 /* Minimal writable flash unit size. In case of NOR flash it is 1 (even249 * though individual bits can be cleared), in case of NAND flash it is250 * one NAND page (or half, or one-fourths of it), in case of ECC-ed NOR251 * it is of ECC block size, etc. It is illegal to have writesize = 0.252 * Any driver registering a struct mtd_info must ensure a writesize of253 * 1 or larger.254 */255 uint32_t writesize;256 257 /*258 * Size of the write buffer used by the MTD. MTD devices having a write259 * buffer can write multiple writesize chunks at a time. E.g. while260 * writing 4 * writesize bytes to a device with 2 * writesize bytes261 * buffer the MTD driver can (but doesn't have to) do 2 writesize262 * operations, but not 4. Currently, all NANDs have writebufsize263 * equivalent to writesize (NAND page size). Some NOR flashes do have264 * writebufsize greater than writesize.265 */266 uint32_t writebufsize;267 268 uint32_t oobsize; // Amount of OOB data per block (e.g. 16)269 uint32_t oobavail; // Available OOB bytes per block270 271 /*272 * If erasesize is a power of 2 then the shift is stored in273 * erasesize_shift otherwise erasesize_shift is zero. Ditto writesize.274 */275 unsigned int erasesize_shift;276 unsigned int writesize_shift;277 /* Masks based on erasesize_shift and writesize_shift */278 unsigned int erasesize_mask;279 unsigned int writesize_mask;280 281 /*282 * read ops return -EUCLEAN if max number of bitflips corrected on any283 * one region comprising an ecc step equals or exceeds this value.284 * Settable by driver, else defaults to ecc_strength. User can override285 * in sysfs. N.B. The meaning of the -EUCLEAN return code has changed;286 * see Documentation/ABI/testing/sysfs-class-mtd for more detail.287 */288 unsigned int bitflip_threshold;289 290 /* Kernel-only stuff starts here. */291 const char *name;292 int index;293 294 /* OOB layout description */295 const struct mtd_ooblayout_ops *ooblayout;296 297 /* NAND pairing scheme, only provided for MLC/TLC NANDs */298 const struct mtd_pairing_scheme *pairing;299 300 /* the ecc step size. */301 unsigned int ecc_step_size;302 303 /* max number of correctible bit errors per ecc step */304 unsigned int ecc_strength;305 306 /* Data for variable erase regions. If numeraseregions is zero,307 * it means that the whole device has erasesize as given above.308 */309 int numeraseregions;310 struct mtd_erase_region_info *eraseregions;311 312 /*313 * Do not call via these pointers, use corresponding mtd_*()314 * wrappers instead.315 */316 int (*_erase) (struct mtd_info *mtd, struct erase_info *instr);317 int (*_point) (struct mtd_info *mtd, loff_t from, size_t len,318 size_t *retlen, void **virt, resource_size_t *phys);319 int (*_unpoint) (struct mtd_info *mtd, loff_t from, size_t len);320 int (*_read) (struct mtd_info *mtd, loff_t from, size_t len,321 size_t *retlen, u_char *buf);322 int (*_write) (struct mtd_info *mtd, loff_t to, size_t len,323 size_t *retlen, const u_char *buf);324 int (*_panic_write) (struct mtd_info *mtd, loff_t to, size_t len,325 size_t *retlen, const u_char *buf);326 int (*_read_oob) (struct mtd_info *mtd, loff_t from,327 struct mtd_oob_ops *ops);328 int (*_write_oob) (struct mtd_info *mtd, loff_t to,329 struct mtd_oob_ops *ops);330 int (*_get_fact_prot_info) (struct mtd_info *mtd, size_t len,331 size_t *retlen, struct otp_info *buf);332 int (*_read_fact_prot_reg) (struct mtd_info *mtd, loff_t from,333 size_t len, size_t *retlen, u_char *buf);334 int (*_get_user_prot_info) (struct mtd_info *mtd, size_t len,335 size_t *retlen, struct otp_info *buf);336 int (*_read_user_prot_reg) (struct mtd_info *mtd, loff_t from,337 size_t len, size_t *retlen, u_char *buf);338 int (*_write_user_prot_reg) (struct mtd_info *mtd, loff_t to,339 size_t len, size_t *retlen,340 const u_char *buf);341 int (*_lock_user_prot_reg) (struct mtd_info *mtd, loff_t from,342 size_t len);343 int (*_erase_user_prot_reg) (struct mtd_info *mtd, loff_t from,344 size_t len);345 int (*_writev) (struct mtd_info *mtd, const struct kvec *vecs,346 unsigned long count, loff_t to, size_t *retlen);347 void (*_sync) (struct mtd_info *mtd);348 int (*_lock) (struct mtd_info *mtd, loff_t ofs, uint64_t len);349 int (*_unlock) (struct mtd_info *mtd, loff_t ofs, uint64_t len);350 int (*_is_locked) (struct mtd_info *mtd, loff_t ofs, uint64_t len);351 int (*_block_isreserved) (struct mtd_info *mtd, loff_t ofs);352 int (*_block_isbad) (struct mtd_info *mtd, loff_t ofs);353 int (*_block_markbad) (struct mtd_info *mtd, loff_t ofs);354 int (*_max_bad_blocks) (struct mtd_info *mtd, loff_t ofs, size_t len);355 int (*_suspend) (struct mtd_info *mtd);356 void (*_resume) (struct mtd_info *mtd);357 void (*_reboot) (struct mtd_info *mtd);358 /*359 * If the driver is something smart, like UBI, it may need to maintain360 * its own reference counting. The below functions are only for driver.361 */362 int (*_get_device) (struct mtd_info *mtd);363 void (*_put_device) (struct mtd_info *mtd);364 365 /*366 * flag indicates a panic write, low level drivers can take appropriate367 * action if required to ensure writes go through368 */369 bool oops_panic_write;370 371 struct notifier_block reboot_notifier; /* default mode before reboot */372 373 /* ECC status information */374 struct mtd_ecc_stats ecc_stats;375 /* Subpage shift (NAND) */376 int subpage_sft;377 378 void *priv;379 380 struct module *owner;381 struct device dev;382 struct kref refcnt;383 struct mtd_debug_info dbg;384 struct nvmem_device *nvmem;385 struct nvmem_device *otp_user_nvmem;386 struct nvmem_device *otp_factory_nvmem;387 388 /*389 * Parent device from the MTD partition point of view.390 *391 * MTD masters do not have any parent, MTD partitions do. The parent392 * MTD device can itself be a partition.393 */394 struct mtd_info *parent;395 396 /* List of partitions attached to this MTD device */397 struct list_head partitions;398 399 struct mtd_part part;400 struct mtd_master master;401};402 403static inline struct mtd_info *mtd_get_master(struct mtd_info *mtd)404{405 while (mtd->parent)406 mtd = mtd->parent;407 408 return mtd;409}410 411static inline u64 mtd_get_master_ofs(struct mtd_info *mtd, u64 ofs)412{413 while (mtd->parent) {414 ofs += mtd->part.offset;415 mtd = mtd->parent;416 }417 418 return ofs;419}420 421static inline bool mtd_is_partition(const struct mtd_info *mtd)422{423 return mtd->parent;424}425 426static inline bool mtd_has_partitions(const struct mtd_info *mtd)427{428 return !list_empty(&mtd->partitions);429}430 431int mtd_ooblayout_ecc(struct mtd_info *mtd, int section,432 struct mtd_oob_region *oobecc);433int mtd_ooblayout_find_eccregion(struct mtd_info *mtd, int eccbyte,434 int *section,435 struct mtd_oob_region *oobregion);436int mtd_ooblayout_get_eccbytes(struct mtd_info *mtd, u8 *eccbuf,437 const u8 *oobbuf, int start, int nbytes);438int mtd_ooblayout_set_eccbytes(struct mtd_info *mtd, const u8 *eccbuf,439 u8 *oobbuf, int start, int nbytes);440int mtd_ooblayout_free(struct mtd_info *mtd, int section,441 struct mtd_oob_region *oobfree);442int mtd_ooblayout_get_databytes(struct mtd_info *mtd, u8 *databuf,443 const u8 *oobbuf, int start, int nbytes);444int mtd_ooblayout_set_databytes(struct mtd_info *mtd, const u8 *databuf,445 u8 *oobbuf, int start, int nbytes);446int mtd_ooblayout_count_freebytes(struct mtd_info *mtd);447int mtd_ooblayout_count_eccbytes(struct mtd_info *mtd);448 449static inline void mtd_set_ooblayout(struct mtd_info *mtd,450 const struct mtd_ooblayout_ops *ooblayout)451{452 mtd->ooblayout = ooblayout;453}454 455static inline void mtd_set_pairing_scheme(struct mtd_info *mtd,456 const struct mtd_pairing_scheme *pairing)457{458 mtd->pairing = pairing;459}460 461static inline void mtd_set_of_node(struct mtd_info *mtd,462 struct device_node *np)463{464 mtd->dev.of_node = np;465 if (!mtd->name)466 of_property_read_string(np, "label", &mtd->name);467}468 469static inline struct device_node *mtd_get_of_node(struct mtd_info *mtd)470{471 return dev_of_node(&mtd->dev);472}473 474static inline u32 mtd_oobavail(struct mtd_info *mtd, struct mtd_oob_ops *ops)475{476 return ops->mode == MTD_OPS_AUTO_OOB ? mtd->oobavail : mtd->oobsize;477}478 479static inline int mtd_max_bad_blocks(struct mtd_info *mtd,480 loff_t ofs, size_t len)481{482 struct mtd_info *master = mtd_get_master(mtd);483 484 if (!master->_max_bad_blocks)485 return -ENOTSUPP;486 487 if (mtd->size < (len + ofs) || ofs < 0)488 return -EINVAL;489 490 return master->_max_bad_blocks(master, mtd_get_master_ofs(mtd, ofs),491 len);492}493 494int mtd_wunit_to_pairing_info(struct mtd_info *mtd, int wunit,495 struct mtd_pairing_info *info);496int mtd_pairing_info_to_wunit(struct mtd_info *mtd,497 const struct mtd_pairing_info *info);498int mtd_pairing_groups(struct mtd_info *mtd);499int mtd_erase(struct mtd_info *mtd, struct erase_info *instr);500int mtd_point(struct mtd_info *mtd, loff_t from, size_t len, size_t *retlen,501 void **virt, resource_size_t *phys);502int mtd_unpoint(struct mtd_info *mtd, loff_t from, size_t len);503unsigned long mtd_get_unmapped_area(struct mtd_info *mtd, unsigned long len,504 unsigned long offset, unsigned long flags);505int mtd_read(struct mtd_info *mtd, loff_t from, size_t len, size_t *retlen,506 u_char *buf);507int mtd_write(struct mtd_info *mtd, loff_t to, size_t len, size_t *retlen,508 const u_char *buf);509int mtd_panic_write(struct mtd_info *mtd, loff_t to, size_t len, size_t *retlen,510 const u_char *buf);511 512int mtd_read_oob(struct mtd_info *mtd, loff_t from, struct mtd_oob_ops *ops);513int mtd_write_oob(struct mtd_info *mtd, loff_t to, struct mtd_oob_ops *ops);514 515int mtd_get_fact_prot_info(struct mtd_info *mtd, size_t len, size_t *retlen,516 struct otp_info *buf);517int mtd_read_fact_prot_reg(struct mtd_info *mtd, loff_t from, size_t len,518 size_t *retlen, u_char *buf);519int mtd_get_user_prot_info(struct mtd_info *mtd, size_t len, size_t *retlen,520 struct otp_info *buf);521int mtd_read_user_prot_reg(struct mtd_info *mtd, loff_t from, size_t len,522 size_t *retlen, u_char *buf);523int mtd_write_user_prot_reg(struct mtd_info *mtd, loff_t to, size_t len,524 size_t *retlen, const u_char *buf);525int mtd_lock_user_prot_reg(struct mtd_info *mtd, loff_t from, size_t len);526int mtd_erase_user_prot_reg(struct mtd_info *mtd, loff_t from, size_t len);527 528int mtd_writev(struct mtd_info *mtd, const struct kvec *vecs,529 unsigned long count, loff_t to, size_t *retlen);530 531static inline void mtd_sync(struct mtd_info *mtd)532{533 struct mtd_info *master = mtd_get_master(mtd);534 535 if (master->_sync)536 master->_sync(master);537}538 539int mtd_lock(struct mtd_info *mtd, loff_t ofs, uint64_t len);540int mtd_unlock(struct mtd_info *mtd, loff_t ofs, uint64_t len);541int mtd_is_locked(struct mtd_info *mtd, loff_t ofs, uint64_t len);542int mtd_block_isreserved(struct mtd_info *mtd, loff_t ofs);543int mtd_block_isbad(struct mtd_info *mtd, loff_t ofs);544int mtd_block_markbad(struct mtd_info *mtd, loff_t ofs);545 546static inline int mtd_suspend(struct mtd_info *mtd)547{548 struct mtd_info *master = mtd_get_master(mtd);549 int ret;550 551 if (master->master.suspended)552 return 0;553 554 ret = master->_suspend ? master->_suspend(master) : 0;555 if (ret)556 return ret;557 558 master->master.suspended = 1;559 return 0;560}561 562static inline void mtd_resume(struct mtd_info *mtd)563{564 struct mtd_info *master = mtd_get_master(mtd);565 566 if (!master->master.suspended)567 return;568 569 if (master->_resume)570 master->_resume(master);571 572 master->master.suspended = 0;573}574 575static inline uint32_t mtd_div_by_eb(uint64_t sz, struct mtd_info *mtd)576{577 if (mtd->erasesize_shift)578 return sz >> mtd->erasesize_shift;579 do_div(sz, mtd->erasesize);580 return sz;581}582 583static inline uint32_t mtd_mod_by_eb(uint64_t sz, struct mtd_info *mtd)584{585 if (mtd->erasesize_shift)586 return sz & mtd->erasesize_mask;587 return do_div(sz, mtd->erasesize);588}589 590/**591 * mtd_align_erase_req - Adjust an erase request to align things on eraseblock592 * boundaries.593 * @mtd: the MTD device this erase request applies on594 * @req: the erase request to adjust595 *596 * This function will adjust @req->addr and @req->len to align them on597 * @mtd->erasesize. Of course we expect @mtd->erasesize to be != 0.598 */599static inline void mtd_align_erase_req(struct mtd_info *mtd,600 struct erase_info *req)601{602 u32 mod;603 604 if (WARN_ON(!mtd->erasesize))605 return;606 607 mod = mtd_mod_by_eb(req->addr, mtd);608 if (mod) {609 req->addr -= mod;610 req->len += mod;611 }612 613 mod = mtd_mod_by_eb(req->addr + req->len, mtd);614 if (mod)615 req->len += mtd->erasesize - mod;616}617 618static inline uint32_t mtd_div_by_ws(uint64_t sz, struct mtd_info *mtd)619{620 if (mtd->writesize_shift)621 return sz >> mtd->writesize_shift;622 do_div(sz, mtd->writesize);623 return sz;624}625 626static inline uint32_t mtd_mod_by_ws(uint64_t sz, struct mtd_info *mtd)627{628 if (mtd->writesize_shift)629 return sz & mtd->writesize_mask;630 return do_div(sz, mtd->writesize);631}632 633static inline int mtd_wunit_per_eb(struct mtd_info *mtd)634{635 struct mtd_info *master = mtd_get_master(mtd);636 637 return master->erasesize / mtd->writesize;638}639 640static inline int mtd_offset_to_wunit(struct mtd_info *mtd, loff_t offs)641{642 return mtd_div_by_ws(mtd_mod_by_eb(offs, mtd), mtd);643}644 645static inline loff_t mtd_wunit_to_offset(struct mtd_info *mtd, loff_t base,646 int wunit)647{648 return base + (wunit * mtd->writesize);649}650 651 652static inline int mtd_has_oob(const struct mtd_info *mtd)653{654 struct mtd_info *master = mtd_get_master((struct mtd_info *)mtd);655 656 return master->_read_oob && master->_write_oob;657}658 659static inline int mtd_type_is_nand(const struct mtd_info *mtd)660{661 return mtd->type == MTD_NANDFLASH || mtd->type == MTD_MLCNANDFLASH;662}663 664static inline int mtd_can_have_bb(const struct mtd_info *mtd)665{666 struct mtd_info *master = mtd_get_master((struct mtd_info *)mtd);667 668 return !!master->_block_isbad;669}670 671 /* Kernel-side ioctl definitions */672 673struct mtd_partition;674struct mtd_part_parser_data;675 676extern int mtd_device_parse_register(struct mtd_info *mtd,677 const char * const *part_probe_types,678 struct mtd_part_parser_data *parser_data,679 const struct mtd_partition *defparts,680 int defnr_parts);681#define mtd_device_register(master, parts, nr_parts) \682 mtd_device_parse_register(master, NULL, NULL, parts, nr_parts)683extern int mtd_device_unregister(struct mtd_info *master);684extern struct mtd_info *get_mtd_device(struct mtd_info *mtd, int num);685extern int __get_mtd_device(struct mtd_info *mtd);686extern void __put_mtd_device(struct mtd_info *mtd);687extern struct mtd_info *of_get_mtd_device_by_node(struct device_node *np);688extern struct mtd_info *get_mtd_device_nm(const char *name);689extern void put_mtd_device(struct mtd_info *mtd);690 691 692struct mtd_notifier {693 void (*add)(struct mtd_info *mtd);694 void (*remove)(struct mtd_info *mtd);695 struct list_head list;696};697 698 699extern void register_mtd_user (struct mtd_notifier *new);700extern int unregister_mtd_user (struct mtd_notifier *old);701void *mtd_kmalloc_up_to(const struct mtd_info *mtd, size_t *size);702 703static inline int mtd_is_bitflip(int err) {704 return err == -EUCLEAN;705}706 707static inline int mtd_is_eccerr(int err) {708 return err == -EBADMSG;709}710 711static inline int mtd_is_bitflip_or_eccerr(int err) {712 return mtd_is_bitflip(err) || mtd_is_eccerr(err);713}714 715unsigned mtd_mmap_capabilities(struct mtd_info *mtd);716 717#ifdef CONFIG_DEBUG_FS718bool mtd_check_expert_analysis_mode(void);719#else720static inline bool mtd_check_expert_analysis_mode(void) { return false; }721#endif722 723 724#endif /* __MTD_MTD_H__ */725