include/linux/mtd/mtd.h

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