kernel-ark/include/linux/mtd/mtd.h
Jörn Engel b38178ee71 [MTD] Document erase interface.
Document mtd erase interface.

Signed-off-by: Jörn Engel <joern@logfs.org>
Signed-off-by: David Woodhouse <dwmw2@infradead.org>
2007-09-21 14:48:33 +01:00

271 lines
8.2 KiB
C

/*
* $Id: mtd.h,v 1.61 2005/11/07 11:14:54 gleixner Exp $
*
* Copyright (C) 1999-2003 David Woodhouse <dwmw2@infradead.org> et al.
*
* Released under GPL
*/
#ifndef __MTD_MTD_H__
#define __MTD_MTD_H__
#include <linux/types.h>
#include <linux/module.h>
#include <linux/uio.h>
#include <linux/notifier.h>
#include <linux/mtd/compatmac.h>
#include <mtd/mtd-abi.h>
#define MTD_CHAR_MAJOR 90
#define MTD_BLOCK_MAJOR 31
#define MAX_MTD_DEVICES 32
#define MTD_ERASE_PENDING 0x01
#define MTD_ERASING 0x02
#define MTD_ERASE_SUSPEND 0x04
#define MTD_ERASE_DONE 0x08
#define MTD_ERASE_FAILED 0x10
/* If the erase fails, fail_addr might indicate exactly which block failed. If
fail_addr = 0xffffffff, the failure was not at the device level or was not
specific to any particular block. */
struct erase_info {
struct mtd_info *mtd;
u_int32_t addr;
u_int32_t len;
u_int32_t fail_addr;
u_long time;
u_long retries;
u_int dev;
u_int cell;
void (*callback) (struct erase_info *self);
u_long priv;
u_char state;
struct erase_info *next;
};
struct mtd_erase_region_info {
u_int32_t offset; /* At which this region starts, from the beginning of the MTD */
u_int32_t erasesize; /* For this region */
u_int32_t numblocks; /* Number of blocks of erasesize in this region */
unsigned long *lockmap; /* If keeping bitmap of locks */
};
/*
* oob operation modes
*
* MTD_OOB_PLACE: oob data are placed at the given offset
* MTD_OOB_AUTO: oob data are automatically placed at the free areas
* which are defined by the ecclayout
* MTD_OOB_RAW: mode to read raw data+oob in one chunk. The oob data
* is inserted into the data. Thats a raw image of the
* flash contents.
*/
typedef enum {
MTD_OOB_PLACE,
MTD_OOB_AUTO,
MTD_OOB_RAW,
} mtd_oob_mode_t;
/**
* struct mtd_oob_ops - oob operation operands
* @mode: operation mode
*
* @len: number of data bytes to write/read
*
* @retlen: number of data bytes written/read
*
* @ooblen: number of oob bytes to write/read
* @oobretlen: number of oob bytes written/read
* @ooboffs: offset of oob data in the oob area (only relevant when
* mode = MTD_OOB_PLACE)
* @datbuf: data buffer - if NULL only oob data are read/written
* @oobbuf: oob data buffer
*
* Note, it is allowed to read more then one OOB area at one go, but not write.
* The interface assumes that the OOB write requests program only one page's
* OOB area.
*/
struct mtd_oob_ops {
mtd_oob_mode_t mode;
size_t len;
size_t retlen;
size_t ooblen;
size_t oobretlen;
uint32_t ooboffs;
uint8_t *datbuf;
uint8_t *oobbuf;
};
struct mtd_info {
u_char type;
u_int32_t flags;
u_int32_t size; // Total size of the MTD
/* "Major" erase size for the device. Naïve users may take this
* to be the only erase size available, or may use the more detailed
* information below if they desire
*/
u_int32_t erasesize;
/* Minimal writable flash unit size. In case of NOR flash it is 1 (even
* though individual bits can be cleared), in case of NAND flash it is
* one NAND page (or half, or one-fourths of it), in case of ECC-ed NOR
* it is of ECC block size, etc. It is illegal to have writesize = 0.
* Any driver registering a struct mtd_info must ensure a writesize of
* 1 or larger.
*/
u_int32_t writesize;
u_int32_t oobsize; // Amount of OOB data per block (e.g. 16)
u_int32_t oobavail; // Available OOB bytes per block
// Kernel-only stuff starts here.
char *name;
int index;
/* ecc layout structure pointer - read only ! */
struct nand_ecclayout *ecclayout;
/* Data for variable erase regions. If numeraseregions is zero,
* it means that the whole device has erasesize as given above.
*/
int numeraseregions;
struct mtd_erase_region_info *eraseregions;
/*
* Erase is an asynchronous operation. Device drivers are supposed
* to call instr->callback() whenever the operation completes, even
* if it completes with a failure.
* Callers are supposed to pass a callback function and wait for it
* to be called before writing to the block.
*/
int (*erase) (struct mtd_info *mtd, struct erase_info *instr);
/* This stuff for eXecute-In-Place */
int (*point) (struct mtd_info *mtd, loff_t from, size_t len, size_t *retlen, u_char **mtdbuf);
/* We probably shouldn't allow XIP if the unpoint isn't a NULL */
void (*unpoint) (struct mtd_info *mtd, u_char * addr, loff_t from, size_t len);
int (*read) (struct mtd_info *mtd, loff_t from, size_t len, size_t *retlen, u_char *buf);
int (*write) (struct mtd_info *mtd, loff_t to, size_t len, size_t *retlen, const u_char *buf);
int (*read_oob) (struct mtd_info *mtd, loff_t from,
struct mtd_oob_ops *ops);
int (*write_oob) (struct mtd_info *mtd, loff_t to,
struct mtd_oob_ops *ops);
/*
* Methods to access the protection register area, present in some
* flash devices. The user data is one time programmable but the
* factory data is read only.
*/
int (*get_fact_prot_info) (struct mtd_info *mtd, struct otp_info *buf, size_t len);
int (*read_fact_prot_reg) (struct mtd_info *mtd, loff_t from, size_t len, size_t *retlen, u_char *buf);
int (*get_user_prot_info) (struct mtd_info *mtd, struct otp_info *buf, size_t len);
int (*read_user_prot_reg) (struct mtd_info *mtd, loff_t from, size_t len, size_t *retlen, u_char *buf);
int (*write_user_prot_reg) (struct mtd_info *mtd, loff_t from, size_t len, size_t *retlen, u_char *buf);
int (*lock_user_prot_reg) (struct mtd_info *mtd, loff_t from, size_t len);
/* kvec-based read/write methods.
NB: The 'count' parameter is the number of _vectors_, each of
which contains an (ofs, len) tuple.
*/
int (*writev) (struct mtd_info *mtd, const struct kvec *vecs, unsigned long count, loff_t to, size_t *retlen);
/* Sync */
void (*sync) (struct mtd_info *mtd);
/* Chip-supported device locking */
int (*lock) (struct mtd_info *mtd, loff_t ofs, size_t len);
int (*unlock) (struct mtd_info *mtd, loff_t ofs, size_t len);
/* Power Management functions */
int (*suspend) (struct mtd_info *mtd);
void (*resume) (struct mtd_info *mtd);
/* Bad block management functions */
int (*block_isbad) (struct mtd_info *mtd, loff_t ofs);
int (*block_markbad) (struct mtd_info *mtd, loff_t ofs);
struct notifier_block reboot_notifier; /* default mode before reboot */
/* ECC status information */
struct mtd_ecc_stats ecc_stats;
/* Subpage shift (NAND) */
int subpage_sft;
void *priv;
struct module *owner;
int usecount;
/* If the driver is something smart, like UBI, it may need to maintain
* its own reference counting. The below functions are only for driver.
* The driver may register its callbacks. These callbacks are not
* supposed to be called by MTD users */
int (*get_device) (struct mtd_info *mtd);
void (*put_device) (struct mtd_info *mtd);
};
/* Kernel-side ioctl definitions */
extern int add_mtd_device(struct mtd_info *mtd);
extern int del_mtd_device (struct mtd_info *mtd);
extern struct mtd_info *get_mtd_device(struct mtd_info *mtd, int num);
extern struct mtd_info *get_mtd_device_nm(const char *name);
extern void put_mtd_device(struct mtd_info *mtd);
struct mtd_notifier {
void (*add)(struct mtd_info *mtd);
void (*remove)(struct mtd_info *mtd);
struct list_head list;
};
extern void register_mtd_user (struct mtd_notifier *new);
extern int unregister_mtd_user (struct mtd_notifier *old);
int default_mtd_writev(struct mtd_info *mtd, const struct kvec *vecs,
unsigned long count, loff_t to, size_t *retlen);
int default_mtd_readv(struct mtd_info *mtd, struct kvec *vecs,
unsigned long count, loff_t from, size_t *retlen);
#ifdef CONFIG_MTD_PARTITIONS
void mtd_erase_callback(struct erase_info *instr);
#else
static inline void mtd_erase_callback(struct erase_info *instr)
{
if (instr->callback)
instr->callback(instr);
}
#endif
/*
* Debugging macro and defines
*/
#define MTD_DEBUG_LEVEL0 (0) /* Quiet */
#define MTD_DEBUG_LEVEL1 (1) /* Audible */
#define MTD_DEBUG_LEVEL2 (2) /* Loud */
#define MTD_DEBUG_LEVEL3 (3) /* Noisy */
#ifdef CONFIG_MTD_DEBUG
#define DEBUG(n, args...) \
do { \
if (n <= CONFIG_MTD_DEBUG_VERBOSE) \
printk(KERN_INFO args); \
} while(0)
#else /* CONFIG_MTD_DEBUG */
#define DEBUG(n, args...) do { } while(0)
#endif /* CONFIG_MTD_DEBUG */
#endif /* __MTD_MTD_H__ */