include/linux/mtd/mtd.h

   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 -1LL
  22
  23 struct mtd_info;
  24
  25 /*
  26  * If the erase fails, fail_addr might indicate exactly which block failed. If
  27  * fail_addr = MTD_FAIL_ADDR_UNKNOWN, the failure was not at the device level
  28  * or was not specific to any particular block.
  29  */
  30 struct erase_info {
  31         uint64_t addr;
  32         uint64_t len;
  33         uint64_t fail_addr;
  34 };
  35
  36 struct 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
  43 struct 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 operands
  51  * @mode:       operation mode
  52  *
  53  * @len:        number of data bytes to write/read
  54  *
  55  * @retlen:     number of data bytes written/read
  56  *
  57  * @ooblen:     number of oob bytes to write/read
  58  * @oobretlen:  number of oob bytes written/read
  59  * @ooboffs:    offset of oob data in the oob area (only relevant when
  60  *              mode = MTD_OPS_PLACE_OOB or MTD_OPS_RAW)
  61  * @datbuf:     data buffer - if NULL only oob data are read/written
  62  * @oobbuf:     oob data buffer
  63  *
  64  * Note, some MTD drivers do not allow you to write more than one OOB area at
  65  * one go. If you try to do that on such an MTD device, -EINVAL will be
  66  * returned. If you want to make your implementation portable on all kind of MTD
  67  * devices you should split the write request into several sub-requests when the
  68  * request crosses a page boundary.
  69  */
  70 struct 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 definition
  84  * @offset: region offset
  85  * @length: region length
  86  *
  87  * This structure describes a region of the OOB area, and is used
  88  * to retrieve ECC or free bytes sections.
  89  * Each section is defined by an offset within the OOB area and a
  90  * length.
  91  */
  92 struct mtd_oob_region {
  93         u32 offset;
  94         u32 length;
  95 };
  96
  97 /*
  98  * struct mtd_ooblayout_ops - NAND OOB layout operations
  99  * @ecc: function returning an ECC region in the OOB area.
 100  *       Should return -ERANGE if %section exceeds the total number of
 101  *       ECC sections.
 102  * @free: function returning a free region in the OOB area.
 103  *        Should return -ERANGE if %section exceeds the total number of
 104  *        free sections.
 105  */
 106 struct 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 information
 115  *
 116  * @pair: pair id
 117  * @group: group id
 118  *
 119  * The term "pair" is used here, even though TLC NANDs might group pages by 3
 120  * (3 bits in a single cell). A pair should regroup all pages that are sharing
 121  * 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 be
 124  * seen as the bit position in the cell: page attached to bit 0 belongs to
 125  * 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-1
 131  *
 132  *  pair-0      page-0          page-4
 133  *  pair-1      page-1          page-5
 134  *  pair-2      page-2          page-8
 135  *  ...
 136  *  pair-127    page-251        page-255
 137  *
 138  *
 139  * Note that the "group" and "pair" terms were extracted from Samsung and
 140  * Hynix datasheets, and might be referenced under other names in other
 141  * datasheets (Micron is describing this concept as "shared pages").
 142  */
 143 struct mtd_pairing_info {
 144         int pair;
 145         int group;
 146 };
 147
 148 /**
 149  * struct mtd_pairing_scheme - page pairing scheme description
 150  *
 151  * @ngroups: number of groups. Should be related to the number of bits
 152  *           per cell.
 153  * @get_info: converts a write-unit (page number within an erase block) into
 154  *            mtd_pairing information (pair + group). This function should
 155  *            fill the info parameter based on the wunit index or return
 156  *            -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 the
 159  *             pairing information described in the info argument. It should
 160  *             return -EINVAL, if there's no wunit corresponding to the
 161  *             passed pairing information.
 162  *
 163  * See mtd_pairing_info documentation for a detailed explanation of the
 164  * pair and group concepts.
 165  *
 166  * The mtd_pairing_scheme structure provides a generic solution to represent
 167  * NAND page pairing scheme. Instead of exposing two big tables to do the
 168  * write-unit <-> (pair + group) conversions, we ask the MTD drivers to
 169  * implement the ->get_info() and ->get_wunit() functions.
 170  *
 171  * MTD users will then be able to query these information by using the
 172  * 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 a
 175  * given pair. This value can be retrieved by MTD users using the
 176  * mtd_pairing_groups() helper.
 177  *
 178  * Examples are given in the mtd_pairing_info_to_wunit() and
 179  * mtd_wunit_to_pairing_info() documentation.
 180  */
 181 struct 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
 189 struct 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 directory
 195  */
 196 struct mtd_debug_info {
 197         struct dentry *dfs_dir;
 198 };
 199
 200 /**
 201  * struct mtd_part - MTD partition specific fields
 202  *
 203  * @node: list node used to add an MTD partition to the parent partition list
 204  * @offset: offset of the partition relatively to the parent offset
 205  * @size: partition size. Should be equal to mtd->size unless
 206  *        MTD_SLC_ON_MLC_EMULATION is set
 207  * @flags: original flags (before the mtdpart logic decided to tweak them based
 208  *         on flash constraints, like eraseblock/pagesize alignment)
 209  *
 210  * This struct is embedded in mtd_info and contains partition-specific
 211  * properties/fields.
 212  */
 213 struct 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 fields
 222  *
 223  * @partitions_lock: lock protecting accesses to the partition list. Protects
 224  *                   not only the master partition list, but also all
 225  *                   sub-partitions.
 226  * @suspended: set to 1 when the device is suspended, 0 otherwise
 227  *
 228  * This struct is embedded in mtd_info and contains master-specific
 229  * properties/fields. The master is the root MTD device from the MTD partition
 230  * point of view.
 231  */
 232 struct mtd_master {
 233         struct mutex partitions_lock;
 234         struct mutex chrdev_lock;
 235         unsigned int suspended : 1;
 236 };
 237
 238 struct mtd_info {
 239         u_char type;
 240         uint32_t flags;
 241         uint64_t size;   // Total size of the MTD
 242
 243         /* "Major" erase size for the device. Naïve users may take this
 244          * to be the only erase size available, or may use the more detailed
 245          * information below if they desire
 246          */
 247         uint32_t erasesize;
 248         /* Minimal writable flash unit size. In case of NOR flash it is 1 (even
 249          * though individual bits can be cleared), in case of NAND flash it is
 250          * one NAND page (or half, or one-fourths of it), in case of ECC-ed NOR
 251          * 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 of
 253          * 1 or larger.
 254          */
 255         uint32_t writesize;
 256
 257         /*
 258          * Size of the write buffer used by the MTD. MTD devices having a write
 259          * buffer can write multiple writesize chunks at a time. E.g. while
 260          * writing 4 * writesize bytes to a device with 2 * writesize bytes
 261          * buffer the MTD driver can (but doesn't have to) do 2 writesize
 262          * operations, but not 4. Currently, all NANDs have writebufsize
 263          * equivalent to writesize (NAND page size). Some NOR flashes do have
 264          * 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 block
 270
 271         /*
 272          * If erasesize is a power of 2 then the shift is stored in
 273          * 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 any
 283          * one region comprising an ecc step equals or exceeds this value.
 284          * Settable by driver, else defaults to ecc_strength.  User can override
 285          * 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 maintain
 360          * 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 appropriate
 367          * action if required to ensure writes go through
 368          */
 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 parent
 392          * 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
 403 static 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
 411 static 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
 421 static inline bool mtd_is_partition(const struct mtd_info *mtd)
 422 {
 423         return mtd->parent;
 424 }
 425
 426 static inline bool mtd_has_partitions(const struct mtd_info *mtd)
 427 {
 428         return !list_empty(&mtd->partitions);
 429 }
 430
 431 int mtd_ooblayout_ecc(struct mtd_info *mtd, int section,
 432                       struct mtd_oob_region *oobecc);
 433 int mtd_ooblayout_find_eccregion(struct mtd_info *mtd, int eccbyte,
 434                                  int *section,
 435                                  struct mtd_oob_region *oobregion);
 436 int mtd_ooblayout_get_eccbytes(struct mtd_info *mtd, u8 *eccbuf,
 437                                const u8 *oobbuf, int start, int nbytes);
 438 int mtd_ooblayout_set_eccbytes(struct mtd_info *mtd, const u8 *eccbuf,
 439                                u8 *oobbuf, int start, int nbytes);
 440 int mtd_ooblayout_free(struct mtd_info *mtd, int section,
 441                        struct mtd_oob_region *oobfree);
 442 int mtd_ooblayout_get_databytes(struct mtd_info *mtd, u8 *databuf,
 443                                 const u8 *oobbuf, int start, int nbytes);
 444 int mtd_ooblayout_set_databytes(struct mtd_info *mtd, const u8 *databuf,
 445                                 u8 *oobbuf, int start, int nbytes);
 446 int mtd_ooblayout_count_freebytes(struct mtd_info *mtd);
 447 int mtd_ooblayout_count_eccbytes(struct mtd_info *mtd);
 448
 449 static inline void mtd_set_ooblayout(struct mtd_info *mtd,
 450                                      const struct mtd_ooblayout_ops *ooblayout)
 451 {
 452         mtd->ooblayout = ooblayout;
 453 }
 454
 455 static inline void mtd_set_pairing_scheme(struct mtd_info *mtd,
 456                                 const struct mtd_pairing_scheme *pairing)
 457 {
 458         mtd->pairing = pairing;
 459 }
 460
 461 static 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
 469 static inline struct device_node *mtd_get_of_node(struct mtd_info *mtd)
 470 {
 471         return dev_of_node(&mtd->dev);
 472 }
 473
 474 static 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
 479 static 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
 494 int mtd_wunit_to_pairing_info(struct mtd_info *mtd, int wunit,
 495                               struct mtd_pairing_info *info);
 496 int mtd_pairing_info_to_wunit(struct mtd_info *mtd,
 497                               const struct mtd_pairing_info *info);
 498 int mtd_pairing_groups(struct mtd_info *mtd);
 499 int mtd_erase(struct mtd_info *mtd, struct erase_info *instr);
 500 int mtd_point(struct mtd_info *mtd, loff_t from, size_t len, size_t *retlen,
 501               void **virt, resource_size_t *phys);
 502 int mtd_unpoint(struct mtd_info *mtd, loff_t from, size_t len);
 503 unsigned long mtd_get_unmapped_area(struct mtd_info *mtd, unsigned long len,
 504                                     unsigned long offset, unsigned long flags);
 505 int mtd_read(struct mtd_info *mtd, loff_t from, size_t len, size_t *retlen,
 506              u_char *buf);
 507 int mtd_write(struct mtd_info *mtd, loff_t to, size_t len, size_t *retlen,
 508               const u_char *buf);
 509 int mtd_panic_write(struct mtd_info *mtd, loff_t to, size_t len, size_t *retlen,
 510                     const u_char *buf);
 511
 512 int mtd_read_oob(struct mtd_info *mtd, loff_t from, struct mtd_oob_ops *ops);
 513 int mtd_write_oob(struct mtd_info *mtd, loff_t to, struct mtd_oob_ops *ops);
 514
 515 int mtd_get_fact_prot_info(struct mtd_info *mtd, size_t len, size_t *retlen,
 516                            struct otp_info *buf);
 517 int mtd_read_fact_prot_reg(struct mtd_info *mtd, loff_t from, size_t len,
 518                            size_t *retlen, u_char *buf);
 519 int mtd_get_user_prot_info(struct mtd_info *mtd, size_t len, size_t *retlen,
 520                            struct otp_info *buf);
 521 int mtd_read_user_prot_reg(struct mtd_info *mtd, loff_t from, size_t len,
 522                            size_t *retlen, u_char *buf);
 523 int mtd_write_user_prot_reg(struct mtd_info *mtd, loff_t to, size_t len,
 524                             size_t *retlen, const u_char *buf);
 525 int mtd_lock_user_prot_reg(struct mtd_info *mtd, loff_t from, size_t len);
 526 int mtd_erase_user_prot_reg(struct mtd_info *mtd, loff_t from, size_t len);
 527
 528 int mtd_writev(struct mtd_info *mtd, const struct kvec *vecs,
 529                unsigned long count, loff_t to, size_t *retlen);
 530
 531 static 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
 539 int mtd_lock(struct mtd_info *mtd, loff_t ofs, uint64_t len);
 540 int mtd_unlock(struct mtd_info *mtd, loff_t ofs, uint64_t len);
 541 int mtd_is_locked(struct mtd_info *mtd, loff_t ofs, uint64_t len);
 542 int mtd_block_isreserved(struct mtd_info *mtd, loff_t ofs);
 543 int mtd_block_isbad(struct mtd_info *mtd, loff_t ofs);
 544 int mtd_block_markbad(struct mtd_info *mtd, loff_t ofs);
 545
 546 static 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
 562 static 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
 575 static 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
 583 static 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 eraseblock
 592  *                       boundaries.
 593  * @mtd: the MTD device this erase request applies on
 594  * @req: the erase request to adjust
 595  *
 596  * This function will adjust @req->addr and @req->len to align them on
 597  * @mtd->erasesize. Of course we expect @mtd->erasesize to be != 0.
 598  */
 599 static 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
 618 static 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
 626 static 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
 633 static 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
 640 static 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
 645 static 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
 652 static 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
 659 static inline int mtd_type_is_nand(const struct mtd_info *mtd)
 660 {
 661         return mtd->type == MTD_NANDFLASH || mtd->type == MTD_MLCNANDFLASH;
 662 }
 663
 664 static 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
 673 struct mtd_partition;
 674 struct mtd_part_parser_data;
 675
 676 extern 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)
 683 extern int mtd_device_unregister(struct mtd_info *master);
 684 extern struct mtd_info *get_mtd_device(struct mtd_info *mtd, int num);
 685 extern int __get_mtd_device(struct mtd_info *mtd);
 686 extern void __put_mtd_device(struct mtd_info *mtd);
 687 extern struct mtd_info *of_get_mtd_device_by_node(struct device_node *np);
 688 extern struct mtd_info *get_mtd_device_nm(const char *name);
 689 extern void put_mtd_device(struct mtd_info *mtd);
 690
 691
 692 struct mtd_notifier {
 693         void (*add)(struct mtd_info *mtd);
 694         void (*remove)(struct mtd_info *mtd);
 695         struct list_head list;
 696 };
 697
 698
 699 extern void register_mtd_user (struct mtd_notifier *new);
 700 extern int unregister_mtd_user (struct mtd_notifier *old);
 701 void *mtd_kmalloc_up_to(const struct mtd_info *mtd, size_t *size);
 702
 703 static inline int mtd_is_bitflip(int err) {
 704         return err == -EUCLEAN;
 705 }
 706
 707 static inline int mtd_is_eccerr(int err) {
 708         return err == -EBADMSG;
 709 }
 710
 711 static inline int mtd_is_bitflip_or_eccerr(int err) {
 712         return mtd_is_bitflip(err) || mtd_is_eccerr(err);
 713 }
 714
 715 unsigned mtd_mmap_capabilities(struct mtd_info *mtd);
 716
 717 #ifdef CONFIG_DEBUG_FS
 718 bool mtd_check_expert_analysis_mode(void);
 719 #else
 720 static inline bool mtd_check_expert_analysis_mode(void) { return false; }
 721 #endif
 722
 723
 724 #endif /* __MTD_MTD_H__ */