include/linux/mtd/mtd.h

   1 /*
   2  * $Id: mtd.h,v 1.61 2005/11/07 11:14:54 gleixner Exp $
   3  *
   4  * Copyright (C) 1999-2003 David Woodhouse <dwmw2@infradead.org> et al.
   5  *
   6  * Released under GPL
   7  */
   8
   9 #ifndef __MTD_MTD_H__
  10 #define __MTD_MTD_H__
  11
  12 #include <linux/types.h>
  13 #include <linux/module.h>
  14 #include <linux/uio.h>
  15 #include <linux/notifier.h>
  16
  17 #include <linux/mtd/compatmac.h>
  18 #include <mtd/mtd-abi.h>
  19
  20 #define MTD_CHAR_MAJOR 90
  21 #define MTD_BLOCK_MAJOR 31
  22 #define MAX_MTD_DEVICES 32
  23
  24 #define MTD_ERASE_PENDING       0x01
  25 #define MTD_ERASING             0x02
  26 #define MTD_ERASE_SUSPEND       0x04
  27 #define MTD_ERASE_DONE          0x08
  28 #define MTD_ERASE_FAILED        0x10
  29
  30 /* If the erase fails, fail_addr might indicate exactly which block failed.  If
  31    fail_addr = 0xffffffff, the failure was not at the device level or was not
  32    specific to any particular block. */
  33 struct erase_info {
  34         struct mtd_info *mtd;
  35         u_int32_t addr;
  36         u_int32_t len;
  37         u_int32_t fail_addr;
  38         u_long time;
  39         u_long retries;
  40         u_int dev;
  41         u_int cell;
  42         void (*callback) (struct erase_info *self);
  43         u_long priv;
  44         u_char state;
  45         struct erase_info *next;
  46 };
  47
  48 struct mtd_erase_region_info {
  49         u_int32_t offset;                       /* At which this region starts, from the beginning of the MTD */
  50         u_int32_t erasesize;            /* For this region */
  51         u_int32_t numblocks;            /* Number of blocks of erasesize in this region */
  52         unsigned long *lockmap;         /* If keeping bitmap of locks */
  53 };
  54
  55 /*
  56  * oob operation modes
  57  *
  58  * MTD_OOB_PLACE:       oob data are placed at the given offset
  59  * MTD_OOB_AUTO:        oob data are automatically placed at the free areas
  60  *                      which are defined by the ecclayout
  61  * MTD_OOB_RAW:         mode to read raw data+oob in one chunk. The oob data
  62  *                      is inserted into the data. Thats a raw image of the
  63  *                      flash contents.
  64  */
  65 typedef enum {
  66         MTD_OOB_PLACE,
  67         MTD_OOB_AUTO,
  68         MTD_OOB_RAW,
  69 } mtd_oob_mode_t;
  70
  71 /**
  72  * struct mtd_oob_ops - oob operation operands
  73  * @mode:       operation mode
  74  *
  75  * @len:        number of data bytes to write/read
  76  *
  77  * @retlen:     number of data bytes written/read
  78  *
  79  * @ooblen:     number of oob bytes to write/read
  80  * @oobretlen:  number of oob bytes written/read
  81  * @ooboffs:    offset of oob data in the oob area (only relevant when
  82  *              mode = MTD_OOB_PLACE)
  83  * @datbuf:     data buffer - if NULL only oob data are read/written
  84  * @oobbuf:     oob data buffer
  85  *
  86  * Note, it is allowed to read more then one OOB area at one go, but not write.
  87  * The interface assumes that the OOB write requests program only one page's
  88  * OOB area.
  89  */
  90 struct mtd_oob_ops {
  91         mtd_oob_mode_t  mode;
  92         size_t          len;
  93         size_t          retlen;
  94         size_t          ooblen;
  95         size_t          oobretlen;
  96         uint32_t        ooboffs;
  97         uint8_t         *datbuf;
  98         uint8_t         *oobbuf;
  99 };
 100
 101 struct mtd_info {
 102         u_char type;
 103         u_int32_t flags;
 104         u_int32_t size;  // Total size of the MTD
 105
 106         /* "Major" erase size for the device. Naïve users may take this
 107          * to be the only erase size available, or may use the more detailed
 108          * information below if they desire
 109          */
 110         u_int32_t erasesize;
 111         /* Minimal writable flash unit size. In case of NOR flash it is 1 (even
 112          * though individual bits can be cleared), in case of NAND flash it is
 113          * one NAND page (or half, or one-fourths of it), in case of ECC-ed NOR
 114          * it is of ECC block size, etc. It is illegal to have writesize = 0.
 115          * Any driver registering a struct mtd_info must ensure a writesize of
 116          * 1 or larger.
 117          */
 118         u_int32_t writesize;
 119
 120         u_int32_t oobsize;   // Amount of OOB data per block (e.g. 16)
 121         u_int32_t oobavail;  // Available OOB bytes per block
 122
 123         // Kernel-only stuff starts here.
 124         char *name;
 125         int index;
 126
 127         /* ecc layout structure pointer - read only ! */
 128         struct nand_ecclayout *ecclayout;
 129
 130         /* Data for variable erase regions. If numeraseregions is zero,
 131          * it means that the whole device has erasesize as given above.
 132          */
 133         int numeraseregions;
 134         struct mtd_erase_region_info *eraseregions;
 135
 136         /*
 137          * Erase is an asynchronous operation.  Device drivers are supposed
 138          * to call instr->callback() whenever the operation completes, even
 139          * if it completes with a failure.
 140          * Callers are supposed to pass a callback function and wait for it
 141          * to be called before writing to the block.
 142          */
 143         int (*erase) (struct mtd_info *mtd, struct erase_info *instr);
 144
 145         /* This stuff for eXecute-In-Place */
 146         /* phys is optional and may be set to NULL */
 147         int (*point) (struct mtd_info *mtd, loff_t from, size_t len,
 148                         size_t *retlen, void **virt, resource_size_t *phys);
 149
 150         /* We probably shouldn't allow XIP if the unpoint isn't a NULL */
 151         void (*unpoint) (struct mtd_info *mtd, loff_t from, size_t len);
 152
 153
 154         int (*read) (struct mtd_info *mtd, loff_t from, size_t len, size_t *retlen, u_char *buf);
 155         int (*write) (struct mtd_info *mtd, loff_t to, size_t len, size_t *retlen, const u_char *buf);
 156
 157         /* In blackbox flight recorder like scenarios we want to make successful
 158            writes in interrupt context. panic_write() is only intended to be
 159            called when its known the kernel is about to panic and we need the
 160            write to succeed. Since the kernel is not going to be running for much
 161            longer, this function can break locks and delay to ensure the write
 162            succeeds (but not sleep). */
 163
 164         int (*panic_write) (struct mtd_info *mtd, loff_t to, size_t len, size_t *retlen, const u_char *buf);
 165
 166         int (*read_oob) (struct mtd_info *mtd, loff_t from,
 167                          struct mtd_oob_ops *ops);
 168         int (*write_oob) (struct mtd_info *mtd, loff_t to,
 169                          struct mtd_oob_ops *ops);
 170
 171         /*
 172          * Methods to access the protection register area, present in some
 173          * flash devices. The user data is one time programmable but the
 174          * factory data is read only.
 175          */
 176         int (*get_fact_prot_info) (struct mtd_info *mtd, struct otp_info *buf, size_t len);
 177         int (*read_fact_prot_reg) (struct mtd_info *mtd, loff_t from, size_t len, size_t *retlen, u_char *buf);
 178         int (*get_user_prot_info) (struct mtd_info *mtd, struct otp_info *buf, size_t len);
 179         int (*read_user_prot_reg) (struct mtd_info *mtd, loff_t from, size_t len, size_t *retlen, u_char *buf);
 180         int (*write_user_prot_reg) (struct mtd_info *mtd, loff_t from, size_t len, size_t *retlen, u_char *buf);
 181         int (*lock_user_prot_reg) (struct mtd_info *mtd, loff_t from, size_t len);
 182
 183         /* kvec-based read/write methods.
 184            NB: The 'count' parameter is the number of _vectors_, each of
 185            which contains an (ofs, len) tuple.
 186         */
 187         int (*writev) (struct mtd_info *mtd, const struct kvec *vecs, unsigned long count, loff_t to, size_t *retlen);
 188
 189         /* Sync */
 190         void (*sync) (struct mtd_info *mtd);
 191
 192         /* Chip-supported device locking */
 193         int (*lock) (struct mtd_info *mtd, loff_t ofs, size_t len);
 194         int (*unlock) (struct mtd_info *mtd, loff_t ofs, size_t len);
 195
 196         /* Power Management functions */
 197         int (*suspend) (struct mtd_info *mtd);
 198         void (*resume) (struct mtd_info *mtd);
 199
 200         /* Bad block management functions */
 201         int (*block_isbad) (struct mtd_info *mtd, loff_t ofs);
 202         int (*block_markbad) (struct mtd_info *mtd, loff_t ofs);
 203
 204         struct notifier_block reboot_notifier;  /* default mode before reboot */
 205
 206         /* ECC status information */
 207         struct mtd_ecc_stats ecc_stats;
 208         /* Subpage shift (NAND) */
 209         int subpage_sft;
 210
 211         void *priv;
 212
 213         struct module *owner;
 214         int usecount;
 215
 216         /* If the driver is something smart, like UBI, it may need to maintain
 217          * its own reference counting. The below functions are only for driver.
 218          * The driver may register its callbacks. These callbacks are not
 219          * supposed to be called by MTD users */
 220         int (*get_device) (struct mtd_info *mtd);
 221         void (*put_device) (struct mtd_info *mtd);
 222 };
 223
 224
 225         /* Kernel-side ioctl definitions */
 226
 227 extern int add_mtd_device(struct mtd_info *mtd);
 228 extern int del_mtd_device (struct mtd_info *mtd);
 229
 230 extern struct mtd_info *get_mtd_device(struct mtd_info *mtd, int num);
 231 extern struct mtd_info *get_mtd_device_nm(const char *name);
 232
 233 extern void put_mtd_device(struct mtd_info *mtd);
 234
 235
 236 struct mtd_notifier {
 237         void (*add)(struct mtd_info *mtd);
 238         void (*remove)(struct mtd_info *mtd);
 239         struct list_head list;
 240 };
 241
 242
 243 extern void register_mtd_user (struct mtd_notifier *new);
 244 extern int unregister_mtd_user (struct mtd_notifier *old);
 245
 246 int default_mtd_writev(struct mtd_info *mtd, const struct kvec *vecs,
 247                        unsigned long count, loff_t to, size_t *retlen);
 248
 249 int default_mtd_readv(struct mtd_info *mtd, struct kvec *vecs,
 250                       unsigned long count, loff_t from, size_t *retlen);
 251
 252 #ifdef CONFIG_MTD_PARTITIONS
 253 void mtd_erase_callback(struct erase_info *instr);
 254 #else
 255 static inline void mtd_erase_callback(struct erase_info *instr)
 256 {
 257         if (instr->callback)
 258                 instr->callback(instr);
 259 }
 260 #endif
 261
 262 /*
 263  * Debugging macro and defines
 264  */
 265 #define MTD_DEBUG_LEVEL0        (0)     /* Quiet   */
 266 #define MTD_DEBUG_LEVEL1        (1)     /* Audible */
 267 #define MTD_DEBUG_LEVEL2        (2)     /* Loud    */
 268 #define MTD_DEBUG_LEVEL3        (3)     /* Noisy   */
 269
 270 #ifdef CONFIG_MTD_DEBUG
 271 #define DEBUG(n, args...)                               \
 272         do {                                            \
 273                 if (n <= CONFIG_MTD_DEBUG_VERBOSE)      \
 274                         printk(KERN_INFO args);         \
 275         } while(0)
 276 #else /* CONFIG_MTD_DEBUG */
 277 #define DEBUG(n, args...) do { } while(0)
 278
 279 #endif /* CONFIG_MTD_DEBUG */
 280
 281 #endif /* __MTD_MTD_H__ */