JFFS for WNR3500Lv2

[tomato.git] / release / src-rt / linux / linux-2.6 / include / linux / mtd / nand.h

/*
 *  linux/include/linux/mtd/nand.h
 *
 *  Copyright (c) 2000 David Woodhouse <dwmw2@mvhi.com>
 *                     Steven J. Hill <sjhill@realitydiluted.com>
 *                     Thomas Gleixner <tglx@linutronix.de>
 *
 * $Id: nand.h,v 1.74 2005/09/15 13:58:50 vwool Exp $
 *
 * This program is free software; you can redistribute it and/or modify
 * it under the terms of the GNU General Public License version 2 as
 * published by the Free Software Foundation.
 *
 * Info:
 *      Contains standard defines and IDs for NAND flash devices
 *
 * Changelog:
 *      See git changelog.
 */
#ifndef __LINUX_MTD_NAND_H
#define __LINUX_MTD_NAND_H

#include <linux/wait.h>
#include <linux/spinlock.h>
#include <linux/mtd/mtd.h>

struct mtd_info;
/* Scan and identify a NAND device */
extern int nand_scan (struct mtd_info *mtd, int max_chips);
/* Separate phases of nand_scan(), allowing board driver to intervene
 * and override command or ECC setup according to flash type */
extern int nand_scan_ident(struct mtd_info *mtd, int max_chips);
extern int nand_scan_tail(struct mtd_info *mtd);

/* Free resources held by the NAND device */
extern void nand_release (struct mtd_info *mtd);

/* Internal helper for board drivers which need to override command function */
extern void nand_wait_ready(struct mtd_info *mtd);

/* The maximum number of NAND chips in an array */
#define NAND_MAX_CHIPS          8

/* This constant declares the max. oobsize / page, which
 * is supported now. If you add a chip with bigger oobsize/page
 * adjust this accordingly.
 */

#ifdef CONFIG_MTD_BRCMNAND
#define NAND_MAX_OOBSIZE        128
#define NAND_MAX_PAGESIZE       4096
#else
#define NAND_MAX_OOBSIZE        64
#define NAND_MAX_PAGESIZE       2048
#endif /* CONFIG_MTD_BRCMNAND */

/*
 * Constants for hardware specific CLE/ALE/NCE function
 *
 * These are bits which can be or'ed to set/clear multiple
 * bits in one go.
 */
/* Select the chip by setting nCE to low */
#define NAND_NCE                0x01
/* Select the command latch by setting CLE to high */
#define NAND_CLE                0x02
/* Select the address latch by setting ALE to high */
#define NAND_ALE                0x04

#ifdef CONFIG_MTD_BRCMNAND
# define NAND_ALE_COL   0x08
# define NAND_ALE_ROW   0x10
#endif /* CONFIG_MTD_BRCMNAND */


#define NAND_CTRL_CLE           (NAND_NCE | NAND_CLE)
#define NAND_CTRL_ALE           (NAND_NCE | NAND_ALE)
#define NAND_CTRL_CHANGE        0x80

/*
 * Standard NAND flash commands
 */
#define NAND_CMD_READ0          0
#define NAND_CMD_READ1          1
#define NAND_CMD_RNDOUT         5
#define NAND_CMD_PAGEPROG       0x10
#define NAND_CMD_READOOB        0x50
#define NAND_CMD_ERASE1         0x60
#define NAND_CMD_STATUS         0x70
#define NAND_CMD_STATUS_MULTI   0x71
#define NAND_CMD_SEQIN          0x80
#define NAND_CMD_RNDIN          0x85
#define NAND_CMD_READID         0x90
#define NAND_CMD_ERASE2         0xd0
#define NAND_CMD_RESET          0xff

/* Extended commands for large page devices */
#define NAND_CMD_READSTART      0x30
#define NAND_CMD_RNDOUTSTART    0xE0
#define NAND_CMD_CACHEDPROG     0x15

/* Extended commands for AG-AND device */
/*
 * Note: the command for NAND_CMD_DEPLETE1 is really 0x00 but
 *       there is no way to distinguish that from NAND_CMD_READ0
 *       until the remaining sequence of commands has been completed
 *       so add a high order bit and mask it off in the command.
 */
#define NAND_CMD_DEPLETE1       0x100
#define NAND_CMD_DEPLETE2       0x38
#define NAND_CMD_STATUS_MULTI   0x71
#define NAND_CMD_STATUS_ERROR   0x72
/* multi-bank error status (banks 0-3) */
#define NAND_CMD_STATUS_ERROR0  0x73
#define NAND_CMD_STATUS_ERROR1  0x74
#define NAND_CMD_STATUS_ERROR2  0x75
#define NAND_CMD_STATUS_ERROR3  0x76
#define NAND_CMD_STATUS_RESET   0x7f
#define NAND_CMD_STATUS_CLEAR   0xff

#define NAND_CMD_NONE           -1

/* Status bits */
#define NAND_STATUS_FAIL        0x01
#define NAND_STATUS_FAIL_N1     0x02
#define NAND_STATUS_TRUE_READY  0x20
#define NAND_STATUS_READY       0x40
#define NAND_STATUS_WP          0x80

/*
 * Constants for ECC_MODES
 */
typedef enum {
        NAND_ECC_NONE,
        NAND_ECC_SOFT,
        NAND_ECC_HW,
        NAND_ECC_HW_SYNDROME,
} nand_ecc_modes_t;

/*
 * Constants for Hardware ECC
 */
/* Reset Hardware ECC for read */
#define NAND_ECC_READ           0
/* Reset Hardware ECC for write */
#define NAND_ECC_WRITE          1
/* Enable Hardware ECC before syndrom is read back from flash */
#define NAND_ECC_READSYN        2

/* Bit mask for flags passed to do_nand_read_ecc */
#define NAND_GET_DEVICE         0x80


/* Option constants for bizarre disfunctionality and real
*  features
*/
/* Chip can not auto increment pages */
#define NAND_NO_AUTOINCR        0x00000001
/* Buswitdh is 16 bit */
#define NAND_BUSWIDTH_16        0x00000002
/* Device supports partial programming without padding */
#define NAND_NO_PADDING         0x00000004
/* Chip has cache program function */
#define NAND_CACHEPRG           0x00000008
/* Chip has copy back function */
#define NAND_COPYBACK           0x00000010
/* AND Chip which has 4 banks and a confusing page / block
 * assignment. See Renesas datasheet for further information */
#define NAND_IS_AND             0x00000020
/* Chip has a array of 4 pages which can be read without
 * additional ready /busy waits */
#define NAND_4PAGE_ARRAY        0x00000040
/* Chip requires that BBT is periodically rewritten to prevent
 * bits from adjacent blocks from 'leaking' in altering data.
 * This happens with the Renesas AG-AND chips, possibly others.  */
#define BBT_AUTO_REFRESH        0x00000080
/* Chip does not require ready check on read. True
 * for all large page devices, as they do not support
 * autoincrement.*/
#define NAND_NO_READRDY         0x00000100
/* Chip does not allow subpage writes */
#define NAND_NO_SUBPAGE_WRITE   0x00000200


/* Options valid for Samsung large page devices */
#define NAND_SAMSUNG_LP_OPTIONS \
        (NAND_NO_PADDING | NAND_CACHEPRG | NAND_COPYBACK)

/* Macros to identify the above */
#define NAND_CANAUTOINCR(chip) (!(chip->options & NAND_NO_AUTOINCR))
#define NAND_MUST_PAD(chip) (!(chip->options & NAND_NO_PADDING))
#define NAND_HAS_CACHEPROG(chip) ((chip->options & NAND_CACHEPRG))
#define NAND_HAS_COPYBACK(chip) ((chip->options & NAND_COPYBACK))

/* Large page NAND with SOFT_ECC should support subpage reads */
/* It's patched from Linux 2.6.27.57 */
#define NAND_SUBPAGE_READ(chip) ((chip->ecc.mode == NAND_ECC_SOFT) \
                                        && (chip->page_shift > 9))


/* Mask to zero out the chip options, which come from the id table */
#define NAND_CHIPOPTIONS_MSK    (0x0000ffff & ~NAND_NO_AUTOINCR)

/* Non chip related options */
/* Use a flash based bad block table. This option is passed to the
 * default bad block table function. */
#define NAND_USE_FLASH_BBT      0x00010000
/* This option skips the bbt scan during initialization. */
#define NAND_SKIP_BBTSCAN       0x00020000
/* This option is defined if the board driver allocates its own buffers
   (e.g. because it needs them DMA-coherent */
#define NAND_OWN_BUFFERS        0x00040000
/* Options set by nand scan */
/* Nand scan has allocated controller struct */
#define NAND_CONTROLLER_ALLOC   0x80000000

/* Cell info constants */
#define NAND_CI_CHIPNR_MSK      0x03
#define NAND_CI_CELLTYPE_MSK    0x0C

#ifdef CONFIG_MTD_BRCMNAND
#define NAND_IS_MLC(chip) ((chip)->cellinfo & NAND_CI_CELLTYPE_MSK)
#endif /* CONFIG_MTD_BRCMNAND */


/*
 * nand_state_t - chip states
 * Enumeration for NAND flash chip state
 */
typedef enum {
        FL_READY,
        FL_READING,
        FL_WRITING,
        FL_ERASING,
        FL_SYNCING,
        FL_CACHEDPRG,
        FL_PM_SUSPENDED,
} nand_state_t;

/* Keep gcc happy */
struct nand_chip;

/**
 * struct nand_hw_control - Control structure for hardware controller (e.g ECC generator) shared among independent devices
 * @lock:               protection lock
 * @active:             the mtd device which holds the controller currently
 * @wq:                 wait queue to sleep on if a NAND operation is in progress
 *                      used instead of the per chip wait queue when a hw controller is available
 */
struct nand_hw_control {
        spinlock_t       lock;
        struct nand_chip *active;
        wait_queue_head_t wq;
};

/**
 * struct nand_ecc_ctrl - Control structure for ecc
 * @mode:       ecc mode
 * @steps:      number of ecc steps per page
 * @size:       data bytes per ecc step
 * @bytes:      ecc bytes per step
 * @total:      total number of ecc bytes per page
 * @prepad:     padding information for syndrome based ecc generators
 * @postpad:    padding information for syndrome based ecc generators
 * @layout:     ECC layout control struct pointer
 * @hwctl:      function to control hardware ecc generator. Must only
 *              be provided if an hardware ECC is available
 * @calculate:  function for ecc calculation or readback from ecc hardware
 * @correct:    function for ecc correction, matching to ecc generator (sw/hw)
 * @read_page_raw:      function to read a raw page without ECC
 * @write_page_raw:     function to write a raw page without ECC
 * @read_page:  function to read a page according to the ecc generator requirements
 * @write_page: function to write a page according to the ecc generator requirements
 * @read_oob:   function to read chip OOB data
 * @write_oob:  function to write chip OOB data
 */
struct nand_ecc_ctrl {
        nand_ecc_modes_t        mode;
#ifdef CONFIG_MTD_BRCMNAND
        int                     level;
        int                     oobsize;
#endif /* CONFIG_MTD_BRCMNAND */
        int                     steps;
        int                     size;
        int                     bytes;
        int                     total;
        int                     prepad;
        int                     postpad;
        struct nand_ecclayout   *layout;
        void                    (*hwctl)(struct mtd_info *mtd, int mode);
        int                     (*calculate)(struct mtd_info *mtd,
                                             const uint8_t *dat,
                                             uint8_t *ecc_code);
        int                     (*correct)(struct mtd_info *mtd, uint8_t *dat,
                                           uint8_t *read_ecc,
                                           uint8_t *calc_ecc);
        int                     (*read_page_raw)(struct mtd_info *mtd,
                                                 struct nand_chip *chip,
                                                 uint8_t *buf);
        void                    (*write_page_raw)(struct mtd_info *mtd,
                                                  struct nand_chip *chip,
                                                  const uint8_t *buf);
        int                     (*read_page)(struct mtd_info *mtd,
                                             struct nand_chip *chip,
                                             uint8_t *buf);
        /* Patched from Linux 2.6.27.57 */
        int                     (*read_subpage)(struct mtd_info *mtd,
                                             struct nand_chip *chip,
                                             uint32_t offs, uint32_t len,
                                             uint8_t *buf);
        void                    (*write_page)(struct mtd_info *mtd,
                                              struct nand_chip *chip,
                                              const uint8_t *buf);
        int                     (*read_oob)(struct mtd_info *mtd,
                                            struct nand_chip *chip,
                                            int page,
                                            int sndcmd);
        int                     (*write_oob)(struct mtd_info *mtd,
                                             struct nand_chip *chip,
                                             int page);
};

/**
 * struct nand_buffers - buffer structure for read/write
 * @ecccalc:    buffer for calculated ecc
 * @ecccode:    buffer for ecc read from flash
 * @databuf:    buffer for data - dynamically sized
 *
 * Do not change the order of buffers. databuf and oobrbuf must be in
 * consecutive order.
 */
struct nand_buffers {
        uint8_t ecccalc[NAND_MAX_OOBSIZE];
        uint8_t ecccode[NAND_MAX_OOBSIZE];
        uint8_t databuf[NAND_MAX_PAGESIZE + NAND_MAX_OOBSIZE];
};

/**
 * struct nand_chip - NAND Private Flash Chip Data
 * @IO_ADDR_R:          [BOARDSPECIFIC] address to read the 8 I/O lines of the flash device
 * @IO_ADDR_W:          [BOARDSPECIFIC] address to write the 8 I/O lines of the flash device
 * @read_byte:          [REPLACEABLE] read one byte from the chip
 * @read_word:          [REPLACEABLE] read one word from the chip
 * @write_buf:          [REPLACEABLE] write data from the buffer to the chip
 * @read_buf:           [REPLACEABLE] read data from the chip into the buffer
 * @verify_buf:         [REPLACEABLE] verify buffer contents against the chip data
 * @select_chip:        [REPLACEABLE] select chip nr
 * @block_bad:          [REPLACEABLE] check, if the block is bad
 * @block_markbad:      [REPLACEABLE] mark the block bad
 * @cmd_ctrl:           [BOARDSPECIFIC] hardwarespecific funtion for controlling
 *                      ALE/CLE/nCE. Also used to write command and address
 * @dev_ready:          [BOARDSPECIFIC] hardwarespecific function for accesing device ready/busy line
 *                      If set to NULL no access to ready/busy is available and the ready/busy information
 *                      is read from the chip status register
 * @cmdfunc:            [REPLACEABLE] hardwarespecific function for writing commands to the chip
 * @waitfunc:           [REPLACEABLE] hardwarespecific function for wait on ready
 * @ecc:                [BOARDSPECIFIC] ecc control ctructure
 * @buffers:            buffer structure for read/write
 * @hwcontrol:          platform-specific hardware control structure
 * @ops:                oob operation operands
 * @erase_cmd:          [INTERN] erase command write function, selectable due to AND support
 * @scan_bbt:           [REPLACEABLE] function to scan bad block table
 * @chip_delay:         [BOARDSPECIFIC] chip dependent delay for transfering data from array to read regs (tR)
 * @wq:                 [INTERN] wait queue to sleep on if a NAND operation is in progress
 * @state:              [INTERN] the current state of the NAND device
 * @oob_poi:            poison value buffer
 * @page_shift:         [INTERN] number of address bits in a page (column address bits)
 * @phys_erase_shift:   [INTERN] number of address bits in a physical eraseblock
 * @bbt_erase_shift:    [INTERN] number of address bits in a bbt entry
 * @chip_shift:         [INTERN] number of address bits in one chip
 * @datbuf:             [INTERN] internal buffer for one page + oob
 * @oobbuf:             [INTERN] oob buffer for one eraseblock
 * @oobdirty:           [INTERN] indicates that oob_buf must be reinitialized
 * @data_poi:           [INTERN] pointer to a data buffer
 * @options:            [BOARDSPECIFIC] various chip options. They can partly be set to inform nand_scan about
 *                      special functionality. See the defines for further explanation
 * @badblockpos:        [INTERN] position of the bad block marker in the oob area
 * @cellinfo:           [INTERN] MLC/multichip data from chip ident
 * @numchips:           [INTERN] number of physical chips
 * @chipsize:           [INTERN] the size of one chip for multichip arrays
 * @pagemask:           [INTERN] page number mask = number of (pages / chip) - 1
 * @pagebuf:            [INTERN] holds the pagenumber which is currently in data_buf
 * @subpagesize:        [INTERN] holds the subpagesize
 * @ecclayout:          [REPLACEABLE] the default ecc placement scheme
 * @bbt:                [INTERN] bad block table pointer
 * @bbt_td:             [REPLACEABLE] bad block table descriptor for flash lookup
 * @bbt_md:             [REPLACEABLE] bad block table mirror descriptor
 * @badblock_pattern:   [REPLACEABLE] bad block scan pattern used for initial bad block scan
 * @controller:         [REPLACEABLE] a pointer to a hardware controller structure
 *                      which is shared among multiple independend devices
 * @priv:               [OPTIONAL] pointer to private chip date
 * @errstat:            [OPTIONAL] hardware specific function to perform additional error status checks
 *                      (determine if errors are correctable)
 * @write_page:         [REPLACEABLE] High-level page write function
 */

struct nand_chip {
        void  __iomem   *IO_ADDR_R;
        void  __iomem   *IO_ADDR_W;

        uint8_t         (*read_byte)(struct mtd_info *mtd);
        u16             (*read_word)(struct mtd_info *mtd);
        void            (*write_buf)(struct mtd_info *mtd, const uint8_t *buf, int len);
        void            (*read_buf)(struct mtd_info *mtd, uint8_t *buf, int len);
        int             (*verify_buf)(struct mtd_info *mtd, const uint8_t *buf, int len);
        void            (*select_chip)(struct mtd_info *mtd, int chip);
        int             (*block_bad)(struct mtd_info *mtd, loff_t ofs, int getchip);
        int             (*block_markbad)(struct mtd_info *mtd, loff_t ofs);
        void            (*cmd_ctrl)(struct mtd_info *mtd, int dat,
                                    unsigned int ctrl);
        int             (*dev_ready)(struct mtd_info *mtd);
        void            (*cmdfunc)(struct mtd_info *mtd, unsigned command, int column, int page_addr);
        int             (*waitfunc)(struct mtd_info *mtd, struct nand_chip *this);
        void            (*erase_cmd)(struct mtd_info *mtd, int page);
        int             (*scan_bbt)(struct mtd_info *mtd);
#ifdef CONFIG_MTD_BRCMNAND
        int             (*erase_bbt)(struct mtd_info *mtd, struct erase_info *instr, int allowbbt);
        int             (*get_device)(struct nand_chip *chip, struct mtd_info *mtd, int new_state);
        void    (*release_device)(struct mtd_info *mtd);
#endif /* CONFIG_MTD_BRCMNAND */
        int             (*errstat)(struct mtd_info *mtd, struct nand_chip *this, int state, int status, int page);
        int             (*write_page)(struct mtd_info *mtd, struct nand_chip *chip,
                                      const uint8_t *buf, int page, int cached, int raw);

        int             chip_delay;
        unsigned int    options;

        int             page_shift;
        int             phys_erase_shift;
        int             bbt_erase_shift;
        int             chip_shift;
        int             numchips;
        unsigned long   chipsize;
        int             pagemask;
        int             pagebuf;
        int             subpagesize;
        uint8_t         cellinfo;
        int             badblockpos;
#ifdef CONFIG_MTD_BRCMNAND
        int             pageidx;
#endif /* CONFIG_MTD_BRCMNAND */

        nand_state_t    state;

        uint8_t         *oob_poi;
        struct nand_hw_control  *controller;
        struct nand_ecclayout   *ecclayout;

        struct nand_ecc_ctrl ecc;
        struct nand_buffers *buffers;
        struct nand_hw_control hwcontrol;

        struct mtd_oob_ops ops;

        uint8_t         *bbt;
        struct nand_bbt_descr   *bbt_td;
        struct nand_bbt_descr   *bbt_md;

        struct nand_bbt_descr   *badblock_pattern;

        void            *priv;
};

/*
 * NAND Flash Manufacturer ID Codes
 */
#define NAND_MFR_TOSHIBA        0x98
#define NAND_MFR_SAMSUNG        0xec
#define NAND_MFR_FUJITSU        0x04
#define NAND_MFR_NATIONAL       0x8f
#define NAND_MFR_RENESAS        0x07
#define NAND_MFR_STMICRO        0x20
#define NAND_MFR_HYNIX          0xad
#define NAND_MFR_MICRON         0x2c

/**
 * struct nand_flash_dev - NAND Flash Device ID Structure
 * @name:       Identify the device type
 * @id:         device ID code
 * @pagesize:   Pagesize in bytes. Either 256 or 512 or 0
 *              If the pagesize is 0, then the real pagesize
 *              and the eraseize are determined from the
 *              extended id bytes in the chip
 * @erasesize:  Size of an erase block in the flash device.
 * @chipsize:   Total chipsize in Mega Bytes
 * @options:    Bitfield to store chip relevant options
 */
struct nand_flash_dev {
        char *name;
        int id;
        unsigned long pagesize;
        unsigned long chipsize;
        unsigned long erasesize;
        unsigned long options;
};

/**
 * struct nand_manufacturers - NAND Flash Manufacturer ID Structure
 * @name:       Manufacturer name
 * @id:         manufacturer ID code of device.
*/
struct nand_manufacturers {
        int id;
        char * name;
};

extern struct nand_flash_dev nand_flash_ids[];
extern struct nand_manufacturers nand_manuf_ids[];

/**
 * struct nand_bbt_descr - bad block table descriptor
 * @options:    options for this descriptor
 * @pages:      the page(s) where we find the bbt, used with option BBT_ABSPAGE
 *              when bbt is searched, then we store the found bbts pages here.
 *              Its an array and supports up to 8 chips now
 * @offs:       offset of the pattern in the oob area of the page
 * @veroffs:    offset of the bbt version counter in the oob are of the page
 * @version:    version read from the bbt page during scan
 * @len:        length of the pattern, if 0 no pattern check is performed
 * @maxblocks:  maximum number of blocks to search for a bbt. This number of
 *              blocks is reserved at the end of the device where the tables are
 *              written.
 * @reserved_block_code: if non-0, this pattern denotes a reserved (rather than
 *              bad) block in the stored bbt
 * @pattern:    pattern to identify bad block table or factory marked good /
 *              bad blocks, can be NULL, if len = 0
 *
 * Descriptor for the bad block table marker and the descriptor for the
 * pattern which identifies good and bad blocks. The assumption is made
 * that the pattern and the version count are always located in the oob area
 * of the first block.
 */
struct nand_bbt_descr {
        int     options;
        int     pages[NAND_MAX_CHIPS];
        int     offs;
        int     veroffs;
        uint8_t version[NAND_MAX_CHIPS];
        int     len;
        int     maxblocks;
        int     reserved_block_code;
        uint8_t *pattern;
};

/* Options for the bad block table descriptors */

/* The number of bits used per block in the bbt on the device */
#define NAND_BBT_NRBITS_MSK     0x0000000F
#define NAND_BBT_1BIT           0x00000001
#define NAND_BBT_2BIT           0x00000002
#define NAND_BBT_4BIT           0x00000004
#define NAND_BBT_8BIT           0x00000008
/* The bad block table is in the last good block of the device */
#define NAND_BBT_LASTBLOCK      0x00000010
/* The bbt is at the given page, else we must scan for the bbt */
#define NAND_BBT_ABSPAGE        0x00000020
/* The bbt is at the given page, else we must scan for the bbt */
#define NAND_BBT_SEARCH         0x00000040
/* bbt is stored per chip on multichip devices */
#define NAND_BBT_PERCHIP        0x00000080
/* bbt has a version counter at offset veroffs */
#define NAND_BBT_VERSION        0x00000100
/* Create a bbt if none axists */
#define NAND_BBT_CREATE         0x00000200
/* Search good / bad pattern through all pages of a block */
#define NAND_BBT_SCANALLPAGES   0x00000400
/* Scan block empty during good / bad block scan */
#define NAND_BBT_SCANEMPTY      0x00000800
/* Write bbt if neccecary */
#define NAND_BBT_WRITE          0x00001000
/* Read and write back block contents when writing bbt */
#define NAND_BBT_SAVECONTENT    0x00002000
/* Search good / bad pattern on the first and the second page */
#define NAND_BBT_SCAN2NDPAGE    0x00004000

/* The maximum number of blocks to scan for a bbt */
#define NAND_BBT_SCAN_MAXBLOCKS 4

extern int nand_scan_bbt(struct mtd_info *mtd, struct nand_bbt_descr *bd);
extern int nand_update_bbt(struct mtd_info *mtd, loff_t offs);
extern int nand_default_bbt(struct mtd_info *mtd);
extern int nand_isbad_bbt(struct mtd_info *mtd, loff_t offs, int allowbbt);
extern int nand_erase_nand(struct mtd_info *mtd, struct erase_info *instr,
                           int allowbbt);
extern int nand_do_read(struct mtd_info *mtd, loff_t from, size_t len,
                        size_t * retlen, uint8_t * buf);

/*
* Constants for oob configuration
*/
#define NAND_SMALL_BADBLOCK_POS         5
#define NAND_LARGE_BADBLOCK_POS         0

/**
 * struct platform_nand_chip - chip level device structure
 * @nr_chips:           max. number of chips to scan for
 * @chip_offset:        chip number offset
 * @nr_partitions:      number of partitions pointed to by partitions (or zero)
 * @partitions:         mtd partition list
 * @chip_delay:         R/B delay value in us
 * @options:            Option flags, e.g. 16bit buswidth
 * @ecclayout:          ecc layout info structure
 * @part_probe_types:   NULL-terminated array of probe types
 * @priv:               hardware controller specific settings
 */
struct platform_nand_chip {
        int                     nr_chips;
        int                     chip_offset;
        int                     nr_partitions;
        struct mtd_partition    *partitions;
        struct nand_ecclayout   *ecclayout;
        int                     chip_delay;
        unsigned int            options;
        const char              **part_probe_types;
        void                    *priv;
};

/**
 * struct platform_nand_ctrl - controller level device structure
 * @hwcontrol:          platform specific hardware control structure
 * @dev_ready:          platform specific function to read ready/busy pin
 * @select_chip:        platform specific chip select function
 * @cmd_ctrl:           platform specific function for controlling
 *                      ALE/CLE/nCE. Also used to write command and address
 * @priv:               private data to transport driver specific settings
 *
 * All fields are optional and depend on the hardware driver requirements
 */
struct platform_nand_ctrl {
        void            (*hwcontrol)(struct mtd_info *mtd, int cmd);
        int             (*dev_ready)(struct mtd_info *mtd);
        void            (*select_chip)(struct mtd_info *mtd, int chip);
        void            (*cmd_ctrl)(struct mtd_info *mtd, int dat,
                                    unsigned int ctrl);
        void            *priv;
};

/**
 * struct platform_nand_data - container structure for platform-specific data
 * @chip:               chip level chip structure
 * @ctrl:               controller level device structure
 */
struct platform_nand_data {
        struct platform_nand_chip       chip;
        struct platform_nand_ctrl       ctrl;
};

/* Some helpers to access the data structures */
static inline
struct platform_nand_chip *get_platform_nandchip(struct mtd_info *mtd)
{
        struct nand_chip *chip = mtd->priv;

        return chip->priv;
}

#endif /* __LINUX_MTD_NAND_H */