include/linux/mtd/nand.h

   1 /* SPDX-License-Identifier: GPL-2.0 */
   2 /*
   3  *  Copyright 2017 - Free Electrons
   4  *
   5  *  Authors:
   6  *      Boris Brezillon <boris.brezillon@free-electrons.com>
   7  *      Peter Pan <peterpandong@micron.com>
   8  */
   9
  10 #ifndef __LINUX_MTD_NAND_H
  11 #define __LINUX_MTD_NAND_H
  12
  13 #include <linux/mtd/mtd.h>
  14 #include <linux/bitops.h>
  15
  16 /**
  17  * struct nand_memory_organization - Memory organization structure
  18  * @bits_per_cell: number of bits per NAND cell
  19  * @pagesize: page size
  20  * @oobsize: OOB area size
  21  * @pages_per_eraseblock: number of pages per eraseblock
  22  * @eraseblocks_per_lun: number of eraseblocks per LUN (Logical Unit Number)
  23  * @planes_per_lun: number of planes per LUN
  24  * @luns_per_target: number of LUN per target (target is a synonym for die)
  25  * @ntargets: total number of targets exposed by the NAND device
  26  */
  27 struct nand_memory_organization {
  28         unsigned int bits_per_cell;
  29         unsigned int pagesize;
  30         unsigned int oobsize;
  31         unsigned int pages_per_eraseblock;
  32         unsigned int eraseblocks_per_lun;
  33         unsigned int planes_per_lun;
  34         unsigned int luns_per_target;
  35         unsigned int ntargets;
  36 };
  37
  38 #define NAND_MEMORG(bpc, ps, os, ppe, epl, ppl, lpt, nt)        \
  39         {                                                       \
  40                 .bits_per_cell = (bpc),                         \
  41                 .pagesize = (ps),                               \
  42                 .oobsize = (os),                                \
  43                 .pages_per_eraseblock = (ppe),                  \
  44                 .eraseblocks_per_lun = (epl),                   \
  45                 .planes_per_lun = (ppl),                        \
  46                 .luns_per_target = (lpt),                       \
  47                 .ntargets = (nt),                               \
  48         }
  49
  50 /**
  51  * struct nand_row_converter - Information needed to convert an absolute offset
  52  *                             into a row address
  53  * @lun_addr_shift: position of the LUN identifier in the row address
  54  * @eraseblock_addr_shift: position of the eraseblock identifier in the row
  55  *                         address
  56  */
  57 struct nand_row_converter {
  58         unsigned int lun_addr_shift;
  59         unsigned int eraseblock_addr_shift;
  60 };
  61
  62 /**
  63  * struct nand_pos - NAND position object
  64  * @target: the NAND target/die
  65  * @lun: the LUN identifier
  66  * @plane: the plane within the LUN
  67  * @eraseblock: the eraseblock within the LUN
  68  * @page: the page within the LUN
  69  *
  70  * These information are usually used by specific sub-layers to select the
  71  * appropriate target/die and generate a row address to pass to the device.
  72  */
  73 struct nand_pos {
  74         unsigned int target;
  75         unsigned int lun;
  76         unsigned int plane;
  77         unsigned int eraseblock;
  78         unsigned int page;
  79 };
  80
  81 /**
  82  * struct nand_page_io_req - NAND I/O request object
  83  * @pos: the position this I/O request is targeting
  84  * @dataoffs: the offset within the page
  85  * @datalen: number of data bytes to read from/write to this page
  86  * @databuf: buffer to store data in or get data from
  87  * @ooboffs: the OOB offset within the page
  88  * @ooblen: the number of OOB bytes to read from/write to this page
  89  * @oobbuf: buffer to store OOB data in or get OOB data from
  90  * @mode: one of the %MTD_OPS_XXX mode
  91  *
  92  * This object is used to pass per-page I/O requests to NAND sub-layers. This
  93  * way all useful information are already formatted in a useful way and
  94  * specific NAND layers can focus on translating these information into
  95  * specific commands/operations.
  96  */
  97 struct nand_page_io_req {
  98         struct nand_pos pos;
  99         unsigned int dataoffs;
 100         unsigned int datalen;
 101         union {
 102                 const void *out;
 103                 void *in;
 104         } databuf;
 105         unsigned int ooboffs;
 106         unsigned int ooblen;
 107         union {
 108                 const void *out;
 109                 void *in;
 110         } oobbuf;
 111         int mode;
 112 };
 113
 114 /**
 115  * struct nand_ecc_req - NAND ECC requirements
 116  * @strength: ECC strength
 117  * @step_size: ECC step/block size
 118  */
 119 struct nand_ecc_req {
 120         unsigned int strength;
 121         unsigned int step_size;
 122 };
 123
 124 #define NAND_ECCREQ(str, stp) { .strength = (str), .step_size = (stp) }
 125
 126 /**
 127  * struct nand_bbt - bad block table object
 128  * @cache: in memory BBT cache
 129  */
 130 struct nand_bbt {
 131         unsigned long *cache;
 132 };
 133
 134 struct nand_device;
 135
 136 /**
 137  * struct nand_ops - NAND operations
 138  * @erase: erase a specific block. No need to check if the block is bad before
 139  *         erasing, this has been taken care of by the generic NAND layer
 140  * @markbad: mark a specific block bad. No need to check if the block is
 141  *           already marked bad, this has been taken care of by the generic
 142  *           NAND layer. This method should just write the BBM (Bad Block
 143  *           Marker) so that future call to struct_nand_ops->isbad() return
 144  *           true
 145  * @isbad: check whether a block is bad or not. This method should just read
 146  *         the BBM and return whether the block is bad or not based on what it
 147  *         reads
 148  *
 149  * These are all low level operations that should be implemented by specialized
 150  * NAND layers (SPI NAND, raw NAND, ...).
 151  */
 152 struct nand_ops {
 153         int (*erase)(struct nand_device *nand, const struct nand_pos *pos);
 154         int (*markbad)(struct nand_device *nand, const struct nand_pos *pos);
 155         bool (*isbad)(struct nand_device *nand, const struct nand_pos *pos);
 156 };
 157
 158 /**
 159  * struct nand_device - NAND device
 160  * @mtd: MTD instance attached to the NAND device
 161  * @memorg: memory layout
 162  * @eccreq: ECC requirements
 163  * @rowconv: position to row address converter
 164  * @bbt: bad block table info
 165  * @ops: NAND operations attached to the NAND device
 166  *
 167  * Generic NAND object. Specialized NAND layers (raw NAND, SPI NAND, OneNAND)
 168  * should declare their own NAND object embedding a nand_device struct (that's
 169  * how inheritance is done).
 170  * struct_nand_device->memorg and struct_nand_device->eccreq should be filled
 171  * at device detection time to reflect the NAND device
 172  * capabilities/requirements. Once this is done nanddev_init() can be called.
 173  * It will take care of converting NAND information into MTD ones, which means
 174  * the specialized NAND layers should never manually tweak
 175  * struct_nand_device->mtd except for the ->_read/write() hooks.
 176  */
 177 struct nand_device {
 178         struct mtd_info *mtd;
 179         struct nand_memory_organization memorg;
 180         struct nand_ecc_req eccreq;
 181         struct nand_row_converter rowconv;
 182         struct nand_bbt bbt;
 183         const struct nand_ops *ops;
 184 };
 185
 186 /**
 187  * struct nand_io_iter - NAND I/O iterator
 188  * @req: current I/O request
 189  * @oobbytes_per_page: maximum number of OOB bytes per page
 190  * @dataleft: remaining number of data bytes to read/write
 191  * @oobleft: remaining number of OOB bytes to read/write
 192  *
 193  * Can be used by specialized NAND layers to iterate over all pages covered
 194  * by an MTD I/O request, which should greatly simplifies the boiler-plate
 195  * code needed to read/write data from/to a NAND device.
 196  */
 197 struct nand_io_iter {
 198         struct nand_page_io_req req;
 199         unsigned int oobbytes_per_page;
 200         unsigned int dataleft;
 201         unsigned int oobleft;
 202 };
 203
 204 /**
 205  * mtd_to_nanddev() - Get the NAND device attached to the MTD instance
 206  * @mtd: MTD instance
 207  *
 208  * Return: the NAND device embedding @mtd.
 209  */
 210 static inline struct nand_device *mtd_to_nanddev(struct mtd_info *mtd)
 211 {
 212         return mtd->priv;
 213 }
 214
 215 /**
 216  * nanddev_to_mtd() - Get the MTD device attached to a NAND device
 217  * @nand: NAND device
 218  *
 219  * Return: the MTD device embedded in @nand.
 220  */
 221 static inline struct mtd_info *nanddev_to_mtd(struct nand_device *nand)
 222 {
 223         return nand->mtd;
 224 }
 225
 226 /*
 227  * nanddev_bits_per_cell() - Get the number of bits per cell
 228  * @nand: NAND device
 229  *
 230  * Return: the number of bits per cell.
 231  */
 232 static inline unsigned int nanddev_bits_per_cell(const struct nand_device *nand)
 233 {
 234         return nand->memorg.bits_per_cell;
 235 }
 236
 237 /**
 238  * nanddev_page_size() - Get NAND page size
 239  * @nand: NAND device
 240  *
 241  * Return: the page size.
 242  */
 243 static inline size_t nanddev_page_size(const struct nand_device *nand)
 244 {
 245         return nand->memorg.pagesize;
 246 }
 247
 248 /**
 249  * nanddev_per_page_oobsize() - Get NAND OOB size
 250  * @nand: NAND device
 251  *
 252  * Return: the OOB size.
 253  */
 254 static inline unsigned int
 255 nanddev_per_page_oobsize(const struct nand_device *nand)
 256 {
 257         return nand->memorg.oobsize;
 258 }
 259
 260 /**
 261  * nanddev_pages_per_eraseblock() - Get the number of pages per eraseblock
 262  * @nand: NAND device
 263  *
 264  * Return: the number of pages per eraseblock.
 265  */
 266 static inline unsigned int
 267 nanddev_pages_per_eraseblock(const struct nand_device *nand)
 268 {
 269         return nand->memorg.pages_per_eraseblock;
 270 }
 271
 272 /**
 273  * nanddev_per_page_oobsize() - Get NAND erase block size
 274  * @nand: NAND device
 275  *
 276  * Return: the eraseblock size.
 277  */
 278 static inline size_t nanddev_eraseblock_size(const struct nand_device *nand)
 279 {
 280         return nand->memorg.pagesize * nand->memorg.pages_per_eraseblock;
 281 }
 282
 283 /**
 284  * nanddev_eraseblocks_per_lun() - Get the number of eraseblocks per LUN
 285  * @nand: NAND device
 286  *
 287  * Return: the number of eraseblocks per LUN.
 288  */
 289 static inline unsigned int
 290 nanddev_eraseblocks_per_lun(const struct nand_device *nand)
 291 {
 292         return nand->memorg.eraseblocks_per_lun;
 293 }
 294
 295 /**
 296  * nanddev_target_size() - Get the total size provided by a single target/die
 297  * @nand: NAND device
 298  *
 299  * Return: the total size exposed by a single target/die in bytes.
 300  */
 301 static inline u64 nanddev_target_size(const struct nand_device *nand)
 302 {
 303         return (u64)nand->memorg.luns_per_target *
 304                nand->memorg.eraseblocks_per_lun *
 305                nand->memorg.pages_per_eraseblock *
 306                nand->memorg.pagesize;
 307 }
 308
 309 /**
 310  * nanddev_ntarget() - Get the total of targets
 311  * @nand: NAND device
 312  *
 313  * Return: the number of targets/dies exposed by @nand.
 314  */
 315 static inline unsigned int nanddev_ntargets(const struct nand_device *nand)
 316 {
 317         return nand->memorg.ntargets;
 318 }
 319
 320 /**
 321  * nanddev_neraseblocks() - Get the total number of erasablocks
 322  * @nand: NAND device
 323  *
 324  * Return: the total number of eraseblocks exposed by @nand.
 325  */
 326 static inline unsigned int nanddev_neraseblocks(const struct nand_device *nand)
 327 {
 328         return (u64)nand->memorg.luns_per_target *
 329                nand->memorg.eraseblocks_per_lun *
 330                nand->memorg.pages_per_eraseblock;
 331 }
 332
 333 /**
 334  * nanddev_size() - Get NAND size
 335  * @nand: NAND device
 336  *
 337  * Return: the total size (in bytes) exposed by @nand.
 338  */
 339 static inline u64 nanddev_size(const struct nand_device *nand)
 340 {
 341         return nanddev_target_size(nand) * nanddev_ntargets(nand);
 342 }
 343
 344 /**
 345  * nanddev_get_memorg() - Extract memory organization info from a NAND device
 346  * @nand: NAND device
 347  *
 348  * This can be used by the upper layer to fill the memorg info before calling
 349  * nanddev_init().
 350  *
 351  * Return: the memorg object embedded in the NAND device.
 352  */
 353 static inline struct nand_memory_organization *
 354 nanddev_get_memorg(struct nand_device *nand)
 355 {
 356         return &nand->memorg;
 357 }
 358
 359 int nanddev_init(struct nand_device *nand, const struct nand_ops *ops,
 360                  struct module *owner);
 361 void nanddev_cleanup(struct nand_device *nand);
 362
 363 /**
 364  * nanddev_register() - Register a NAND device
 365  * @nand: NAND device
 366  *
 367  * Register a NAND device.
 368  * This function is just a wrapper around mtd_device_register()
 369  * registering the MTD device embedded in @nand.
 370  *
 371  * Return: 0 in case of success, a negative error code otherwise.
 372  */
 373 static inline int nanddev_register(struct nand_device *nand)
 374 {
 375         return mtd_device_register(nand->mtd, NULL, 0);
 376 }
 377
 378 /**
 379  * nanddev_unregister() - Unregister a NAND device
 380  * @nand: NAND device
 381  *
 382  * Unregister a NAND device.
 383  * This function is just a wrapper around mtd_device_unregister()
 384  * unregistering the MTD device embedded in @nand.
 385  *
 386  * Return: 0 in case of success, a negative error code otherwise.
 387  */
 388 static inline int nanddev_unregister(struct nand_device *nand)
 389 {
 390         return mtd_device_unregister(nand->mtd);
 391 }
 392
 393 /**
 394  * nanddev_set_of_node() - Attach a DT node to a NAND device
 395  * @nand: NAND device
 396  * @np: DT node
 397  *
 398  * Attach a DT node to a NAND device.
 399  */
 400 static inline void nanddev_set_of_node(struct nand_device *nand,
 401                                        const struct device_node *np)
 402 {
 403         mtd_set_of_node(nand->mtd, np);
 404 }
 405
 406 /**
 407  * nanddev_get_of_node() - Retrieve the DT node attached to a NAND device
 408  * @nand: NAND device
 409  *
 410  * Return: the DT node attached to @nand.
 411  */
 412 static inline const struct device_node *nanddev_get_of_node(struct nand_device *nand)
 413 {
 414         return mtd_get_of_node(nand->mtd);
 415 }
 416
 417 /**
 418  * nanddev_offs_to_pos() - Convert an absolute NAND offset into a NAND position
 419  * @nand: NAND device
 420  * @offs: absolute NAND offset (usually passed by the MTD layer)
 421  * @pos: a NAND position object to fill in
 422  *
 423  * Converts @offs into a nand_pos representation.
 424  *
 425  * Return: the offset within the NAND page pointed by @pos.
 426  */
 427 static inline unsigned int nanddev_offs_to_pos(struct nand_device *nand,
 428                                                loff_t offs,
 429                                                struct nand_pos *pos)
 430 {
 431         unsigned int pageoffs;
 432         u64 tmp = offs;
 433
 434         pageoffs = do_div(tmp, nand->memorg.pagesize);
 435         pos->page = do_div(tmp, nand->memorg.pages_per_eraseblock);
 436         pos->eraseblock = do_div(tmp, nand->memorg.eraseblocks_per_lun);
 437         pos->plane = pos->eraseblock % nand->memorg.planes_per_lun;
 438         pos->lun = do_div(tmp, nand->memorg.luns_per_target);
 439         pos->target = tmp;
 440
 441         return pageoffs;
 442 }
 443
 444 /**
 445  * nanddev_pos_cmp() - Compare two NAND positions
 446  * @a: First NAND position
 447  * @b: Second NAND position
 448  *
 449  * Compares two NAND positions.
 450  *
 451  * Return: -1 if @a < @b, 0 if @a == @b and 1 if @a > @b.
 452  */
 453 static inline int nanddev_pos_cmp(const struct nand_pos *a,
 454                                   const struct nand_pos *b)
 455 {
 456         if (a->target != b->target)
 457                 return a->target < b->target ? -1 : 1;
 458
 459         if (a->lun != b->lun)
 460                 return a->lun < b->lun ? -1 : 1;
 461
 462         if (a->eraseblock != b->eraseblock)
 463                 return a->eraseblock < b->eraseblock ? -1 : 1;
 464
 465         if (a->page != b->page)
 466                 return a->page < b->page ? -1 : 1;
 467
 468         return 0;
 469 }
 470
 471 /**
 472  * nanddev_pos_to_offs() - Convert a NAND position into an absolute offset
 473  * @nand: NAND device
 474  * @pos: the NAND position to convert
 475  *
 476  * Converts @pos NAND position into an absolute offset.
 477  *
 478  * Return: the absolute offset. Note that @pos points to the beginning of a
 479  *         page, if one wants to point to a specific offset within this page
 480  *         the returned offset has to be adjusted manually.
 481  */
 482 static inline loff_t nanddev_pos_to_offs(struct nand_device *nand,
 483                                          const struct nand_pos *pos)
 484 {
 485         unsigned int npages;
 486
 487         npages = pos->page +
 488                  ((pos->eraseblock +
 489                    (pos->lun +
 490                     (pos->target * nand->memorg.luns_per_target)) *
 491                    nand->memorg.eraseblocks_per_lun) *
 492                   nand->memorg.pages_per_eraseblock);
 493
 494         return (loff_t)npages * nand->memorg.pagesize;
 495 }
 496
 497 /**
 498  * nanddev_pos_to_row() - Extract a row address from a NAND position
 499  * @nand: NAND device
 500  * @pos: the position to convert
 501  *
 502  * Converts a NAND position into a row address that can then be passed to the
 503  * device.
 504  *
 505  * Return: the row address extracted from @pos.
 506  */
 507 static inline unsigned int nanddev_pos_to_row(struct nand_device *nand,
 508                                               const struct nand_pos *pos)
 509 {
 510         return (pos->lun << nand->rowconv.lun_addr_shift) |
 511                (pos->eraseblock << nand->rowconv.eraseblock_addr_shift) |
 512                pos->page;
 513 }
 514
 515 /**
 516  * nanddev_pos_next_target() - Move a position to the next target/die
 517  * @nand: NAND device
 518  * @pos: the position to update
 519  *
 520  * Updates @pos to point to the start of the next target/die. Useful when you
 521  * want to iterate over all targets/dies of a NAND device.
 522  */
 523 static inline void nanddev_pos_next_target(struct nand_device *nand,
 524                                            struct nand_pos *pos)
 525 {
 526         pos->page = 0;
 527         pos->plane = 0;
 528         pos->eraseblock = 0;
 529         pos->lun = 0;
 530         pos->target++;
 531 }
 532
 533 /**
 534  * nanddev_pos_next_lun() - Move a position to the next LUN
 535  * @nand: NAND device
 536  * @pos: the position to update
 537  *
 538  * Updates @pos to point to the start of the next LUN. Useful when you want to
 539  * iterate over all LUNs of a NAND device.
 540  */
 541 static inline void nanddev_pos_next_lun(struct nand_device *nand,
 542                                         struct nand_pos *pos)
 543 {
 544         if (pos->lun >= nand->memorg.luns_per_target - 1)
 545                 return nanddev_pos_next_target(nand, pos);
 546
 547         pos->lun++;
 548         pos->page = 0;
 549         pos->plane = 0;
 550         pos->eraseblock = 0;
 551 }
 552
 553 /**
 554  * nanddev_pos_next_eraseblock() - Move a position to the next eraseblock
 555  * @nand: NAND device
 556  * @pos: the position to update
 557  *
 558  * Updates @pos to point to the start of the next eraseblock. Useful when you
 559  * want to iterate over all eraseblocks of a NAND device.
 560  */
 561 static inline void nanddev_pos_next_eraseblock(struct nand_device *nand,
 562                                                struct nand_pos *pos)
 563 {
 564         if (pos->eraseblock >= nand->memorg.eraseblocks_per_lun - 1)
 565                 return nanddev_pos_next_lun(nand, pos);
 566
 567         pos->eraseblock++;
 568         pos->page = 0;
 569         pos->plane = pos->eraseblock % nand->memorg.planes_per_lun;
 570 }
 571
 572 /**
 573  * nanddev_pos_next_eraseblock() - Move a position to the next page
 574  * @nand: NAND device
 575  * @pos: the position to update
 576  *
 577  * Updates @pos to point to the start of the next page. Useful when you want to
 578  * iterate over all pages of a NAND device.
 579  */
 580 static inline void nanddev_pos_next_page(struct nand_device *nand,
 581                                          struct nand_pos *pos)
 582 {
 583         if (pos->page >= nand->memorg.pages_per_eraseblock - 1)
 584                 return nanddev_pos_next_eraseblock(nand, pos);
 585
 586         pos->page++;
 587 }
 588
 589 /**
 590  * nand_io_iter_init - Initialize a NAND I/O iterator
 591  * @nand: NAND device
 592  * @offs: absolute offset
 593  * @req: MTD request
 594  * @iter: NAND I/O iterator
 595  *
 596  * Initializes a NAND iterator based on the information passed by the MTD
 597  * layer.
 598  */
 599 static inline void nanddev_io_iter_init(struct nand_device *nand,
 600                                         loff_t offs, struct mtd_oob_ops *req,
 601                                         struct nand_io_iter *iter)
 602 {
 603         struct mtd_info *mtd = nanddev_to_mtd(nand);
 604
 605         iter->req.mode = req->mode;
 606         iter->req.dataoffs = nanddev_offs_to_pos(nand, offs, &iter->req.pos);
 607         iter->req.ooboffs = req->ooboffs;
 608         iter->oobbytes_per_page = mtd_oobavail(mtd, req);
 609         iter->dataleft = req->len;
 610         iter->oobleft = req->ooblen;
 611         iter->req.databuf.in = req->datbuf;
 612         iter->req.datalen = min_t(unsigned int,
 613                                   nand->memorg.pagesize - iter->req.dataoffs,
 614                                   iter->dataleft);
 615         iter->req.oobbuf.in = req->oobbuf;
 616         iter->req.ooblen = min_t(unsigned int,
 617                                  iter->oobbytes_per_page - iter->req.ooboffs,
 618                                  iter->oobleft);
 619 }
 620
 621 /**
 622  * nand_io_iter_next_page - Move to the next page
 623  * @nand: NAND device
 624  * @iter: NAND I/O iterator
 625  *
 626  * Updates the @iter to point to the next page.
 627  */
 628 static inline void nanddev_io_iter_next_page(struct nand_device *nand,
 629                                              struct nand_io_iter *iter)
 630 {
 631         nanddev_pos_next_page(nand, &iter->req.pos);
 632         iter->dataleft -= iter->req.datalen;
 633         iter->req.databuf.in += iter->req.datalen;
 634         iter->oobleft -= iter->req.ooblen;
 635         iter->req.oobbuf.in += iter->req.ooblen;
 636         iter->req.dataoffs = 0;
 637         iter->req.ooboffs = 0;
 638         iter->req.datalen = min_t(unsigned int, nand->memorg.pagesize,
 639                                   iter->dataleft);
 640         iter->req.ooblen = min_t(unsigned int, iter->oobbytes_per_page,
 641                                  iter->oobleft);
 642 }
 643
 644 /**
 645  * nand_io_iter_end - Should end iteration or not
 646  * @nand: NAND device
 647  * @iter: NAND I/O iterator
 648  *
 649  * Check whether @iter has reached the end of the NAND portion it was asked to
 650  * iterate on or not.
 651  *
 652  * Return: true if @iter has reached the end of the iteration request, false
 653  *         otherwise.
 654  */
 655 static inline bool nanddev_io_iter_end(struct nand_device *nand,
 656                                        const struct nand_io_iter *iter)
 657 {
 658         if (iter->dataleft || iter->oobleft)
 659                 return false;
 660
 661         return true;
 662 }
 663
 664 /**
 665  * nand_io_for_each_page - Iterate over all NAND pages contained in an MTD I/O
 666  *                         request
 667  * @nand: NAND device
 668  * @start: start address to read/write from
 669  * @req: MTD I/O request
 670  * @iter: NAND I/O iterator
 671  *
 672  * Should be used for iterate over pages that are contained in an MTD request.
 673  */
 674 #define nanddev_io_for_each_page(nand, start, req, iter)                \
 675         for (nanddev_io_iter_init(nand, start, req, iter);              \
 676              !nanddev_io_iter_end(nand, iter);                          \
 677              nanddev_io_iter_next_page(nand, iter))
 678
 679 bool nanddev_isbad(struct nand_device *nand, const struct nand_pos *pos);
 680 bool nanddev_isreserved(struct nand_device *nand, const struct nand_pos *pos);
 681 int nanddev_erase(struct nand_device *nand, const struct nand_pos *pos);
 682 int nanddev_markbad(struct nand_device *nand, const struct nand_pos *pos);
 683
 684 /* BBT related functions */
 685 enum nand_bbt_block_status {
 686         NAND_BBT_BLOCK_STATUS_UNKNOWN,
 687         NAND_BBT_BLOCK_GOOD,
 688         NAND_BBT_BLOCK_WORN,
 689         NAND_BBT_BLOCK_RESERVED,
 690         NAND_BBT_BLOCK_FACTORY_BAD,
 691         NAND_BBT_BLOCK_NUM_STATUS,
 692 };
 693
 694 int nanddev_bbt_init(struct nand_device *nand);
 695 void nanddev_bbt_cleanup(struct nand_device *nand);
 696 int nanddev_bbt_update(struct nand_device *nand);
 697 int nanddev_bbt_get_block_status(const struct nand_device *nand,
 698                                  unsigned int entry);
 699 int nanddev_bbt_set_block_status(struct nand_device *nand, unsigned int entry,
 700                                  enum nand_bbt_block_status status);
 701 int nanddev_bbt_markbad(struct nand_device *nand, unsigned int block);
 702
 703 /**
 704  * nanddev_bbt_pos_to_entry() - Convert a NAND position into a BBT entry
 705  * @nand: NAND device
 706  * @pos: the NAND position we want to get BBT entry for
 707  *
 708  * Return the BBT entry used to store information about the eraseblock pointed
 709  * by @pos.
 710  *
 711  * Return: the BBT entry storing information about eraseblock pointed by @pos.
 712  */
 713 static inline unsigned int nanddev_bbt_pos_to_entry(struct nand_device *nand,
 714                                                     const struct nand_pos *pos)
 715 {
 716         return pos->eraseblock +
 717                ((pos->lun + (pos->target * nand->memorg.luns_per_target)) *
 718                 nand->memorg.eraseblocks_per_lun);
 719 }
 720
 721 /**
 722  * nanddev_bbt_is_initialized() - Check if the BBT has been initialized
 723  * @nand: NAND device
 724  *
 725  * Return: true if the BBT has been initialized, false otherwise.
 726  */
 727 static inline bool nanddev_bbt_is_initialized(struct nand_device *nand)
 728 {
 729         return !!nand->bbt.cache;
 730 }
 731
 732 /* MTD -> NAND helper functions. */
 733 int nanddev_mtd_erase(struct mtd_info *mtd, struct erase_info *einfo);
 734
 735 #endif /* __LINUX_MTD_NAND_H */