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 #include <asm/div64.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 #define MTD_FAIL_ADDR_UNKNOWN -1LL
  31
  32 /* If the erase fails, fail_addr might indicate exactly which block failed.  If
  33    fail_addr = MTD_FAIL_ADDR_UNKNOWN, the failure was not at the device level or was not
  34    specific to any particular block. */
  35 struct erase_info {
  36         struct mtd_info *mtd;
  37         uint64_t addr;
  38         uint64_t len;
  39         uint64_t fail_addr;
  40         u_long time;
  41         u_long retries;
  42         unsigned dev;
  43         unsigned cell;
  44         void (*callback) (struct erase_info *self);
  45         u_long priv;
  46         u_char state;
  47         struct erase_info *next;
  48 };
  49
  50 struct mtd_erase_region_info {
  51         uint64_t offset;                        /* At which this region starts, from the beginning of the MTD */
  52         uint32_t erasesize;             /* For this region */
  53         uint32_t numblocks;             /* Number of blocks of erasesize in this region */
  54         unsigned long *lockmap;         /* If keeping bitmap of locks */
  55 };
  56
  57 /*
  58  * oob operation modes
  59  *
  60  * MTD_OOB_PLACE:       oob data are placed at the given offset
  61  * MTD_OOB_AUTO:        oob data are automatically placed at the free areas
  62  *                      which are defined by the ecclayout
  63  * MTD_OOB_RAW:         mode to read raw data+oob in one chunk. The oob data
  64  *                      is inserted into the data. Thats a raw image of the
  65  *                      flash contents.
  66  */
  67 typedef enum {
  68         MTD_OOB_PLACE,
  69         MTD_OOB_AUTO,
  70         MTD_OOB_RAW,
  71 } mtd_oob_mode_t;
  72
  73 /**
  74  * struct mtd_oob_ops - oob operation operands
  75  * @mode:       operation mode
  76  *
  77  * @len:        number of data bytes to write/read
  78  *
  79  * @retlen:     number of data bytes written/read
  80  *
  81  * @ooblen:     number of oob bytes to write/read
  82  * @oobretlen:  number of oob bytes written/read
  83  * @ooboffs:    offset of oob data in the oob area (only relevant when
  84  *              mode = MTD_OOB_PLACE)
  85  * @datbuf:     data buffer - if NULL only oob data are read/written
  86  * @oobbuf:     oob data buffer
  87  *
  88  * Note, it is allowed to read more than one OOB area at one go, but not write.
  89  * The interface assumes that the OOB write requests program only one page's
  90  * OOB area.
  91  */
  92 struct mtd_oob_ops {
  93         mtd_oob_mode_t  mode;
  94         size_t          len;
  95         size_t          retlen;
  96         size_t          ooblen;
  97         size_t          oobretlen;
  98         uint32_t        ooboffs;
  99         uint8_t         *datbuf;
 100         uint8_t         *oobbuf;
 101 };
 102
 103 struct mtd_info {
 104         u_char type;
 105         uint32_t flags;
 106         uint64_t size;   // Total size of the MTD
 107
 108         /* "Major" erase size for the device. Naïve users may take this
 109          * to be the only erase size available, or may use the more detailed
 110          * information below if they desire
 111          */
 112         uint32_t erasesize;
 113         /* Minimal writable flash unit size. In case of NOR flash it is 1 (even
 114          * though individual bits can be cleared), in case of NAND flash it is
 115          * one NAND page (or half, or one-fourths of it), in case of ECC-ed NOR
 116          * it is of ECC block size, etc. It is illegal to have writesize = 0.
 117          * Any driver registering a struct mtd_info must ensure a writesize of
 118          * 1 or larger.
 119          */
 120         uint32_t writesize;
 121
 122         uint32_t oobsize;   // Amount of OOB data per block (e.g. 16)
 123         uint32_t oobavail;  // Available OOB bytes per block
 124
 125         /*
 126          * If erasesize is a power of 2 then the shift is stored in
 127          * erasesize_shift otherwise erasesize_shift is zero. Ditto writesize.
 128          */
 129         unsigned int erasesize_shift;
 130         unsigned int writesize_shift;
 131         /* Masks based on erasesize_shift and writesize_shift */
 132         unsigned int erasesize_mask;
 133         unsigned int writesize_mask;
 134
 135         // Kernel-only stuff starts here.
 136         const char *name;
 137         int index;
 138
 139         /* ecc layout structure pointer - read only ! */
 140         struct nand_ecclayout *ecclayout;
 141
 142         /* Data for variable erase regions. If numeraseregions is zero,
 143          * it means that the whole device has erasesize as given above.
 144          */
 145         int numeraseregions;
 146         struct mtd_erase_region_info *eraseregions;
 147
 148         /*
 149          * Erase is an asynchronous operation.  Device drivers are supposed
 150          * to call instr->callback() whenever the operation completes, even
 151          * if it completes with a failure.
 152          * Callers are supposed to pass a callback function and wait for it
 153          * to be called before writing to the block.
 154          */
 155         int (*erase) (struct mtd_info *mtd, struct erase_info *instr);
 156
 157         /* This stuff for eXecute-In-Place */
 158         /* phys is optional and may be set to NULL */
 159         int (*point) (struct mtd_info *mtd, loff_t from, size_t len,
 160                         size_t *retlen, void **virt, resource_size_t *phys);
 161
 162         /* We probably shouldn't allow XIP if the unpoint isn't a NULL */
 163         void (*unpoint) (struct mtd_info *mtd, loff_t from, size_t len);
 164
 165
 166         int (*read) (struct mtd_info *mtd, loff_t from, size_t len, size_t *retlen, u_char *buf);
 167         int (*write) (struct mtd_info *mtd, loff_t to, size_t len, size_t *retlen, const u_char *buf);
 168
 169         /* In blackbox flight recorder like scenarios we want to make successful
 170            writes in interrupt context. panic_write() is only intended to be
 171            called when its known the kernel is about to panic and we need the
 172            write to succeed. Since the kernel is not going to be running for much
 173            longer, this function can break locks and delay to ensure the write
 174            succeeds (but not sleep). */
 175
 176         int (*panic_write) (struct mtd_info *mtd, loff_t to, size_t len, size_t *retlen, const u_char *buf);
 177
 178         int (*read_oob) (struct mtd_info *mtd, loff_t from,
 179                          struct mtd_oob_ops *ops);
 180         int (*write_oob) (struct mtd_info *mtd, loff_t to,
 181                          struct mtd_oob_ops *ops);
 182
 183         /*
 184          * Methods to access the protection register area, present in some
 185          * flash devices. The user data is one time programmable but the
 186          * factory data is read only.
 187          */
 188         int (*get_fact_prot_info) (struct mtd_info *mtd, struct otp_info *buf, size_t len);
 189         int (*read_fact_prot_reg) (struct mtd_info *mtd, loff_t from, size_t len, size_t *retlen, u_char *buf);
 190         int (*get_user_prot_info) (struct mtd_info *mtd, struct otp_info *buf, size_t len);
 191         int (*read_user_prot_reg) (struct mtd_info *mtd, loff_t from, size_t len, size_t *retlen, u_char *buf);
 192         int (*write_user_prot_reg) (struct mtd_info *mtd, loff_t from, size_t len, size_t *retlen, u_char *buf);
 193         int (*lock_user_prot_reg) (struct mtd_info *mtd, loff_t from, size_t len);
 194
 195         /* kvec-based read/write methods.
 196            NB: The 'count' parameter is the number of _vectors_, each of
 197            which contains an (ofs, len) tuple.
 198         */
 199         int (*writev) (struct mtd_info *mtd, const struct kvec *vecs, unsigned long count, loff_t to, size_t *retlen);
 200
 201         /* Sync */
 202         void (*sync) (struct mtd_info *mtd);
 203
 204         /* Chip-supported device locking */
 205         int (*lock) (struct mtd_info *mtd, loff_t ofs, uint64_t len);
 206         int (*unlock) (struct mtd_info *mtd, loff_t ofs, uint64_t len);
 207
 208         /* Power Management functions */
 209         int (*suspend) (struct mtd_info *mtd);
 210         void (*resume) (struct mtd_info *mtd);
 211
 212         /* Bad block management functions */
 213         int (*block_isbad) (struct mtd_info *mtd, loff_t ofs);
 214         int (*block_markbad) (struct mtd_info *mtd, loff_t ofs);
 215
 216         struct notifier_block reboot_notifier;  /* default mode before reboot */
 217
 218         /* ECC status information */
 219         struct mtd_ecc_stats ecc_stats;
 220         /* Subpage shift (NAND) */
 221         int subpage_sft;
 222
 223         void *priv;
 224
 225         struct module *owner;
 226         int usecount;
 227
 228         /* If the driver is something smart, like UBI, it may need to maintain
 229          * its own reference counting. The below functions are only for driver.
 230          * The driver may register its callbacks. These callbacks are not
 231          * supposed to be called by MTD users */
 232         int (*get_device) (struct mtd_info *mtd);
 233         void (*put_device) (struct mtd_info *mtd);
 234 };
 235
 236 static inline uint32_t mtd_div_by_eb(uint64_t sz, struct mtd_info *mtd)
 237 {
 238         if (mtd->erasesize_shift)
 239                 return sz >> mtd->erasesize_shift;
 240         do_div(sz, mtd->erasesize);
 241         return sz;
 242 }
 243
 244 static inline uint32_t mtd_mod_by_eb(uint64_t sz, struct mtd_info *mtd)
 245 {
 246         if (mtd->erasesize_shift)
 247                 return sz & mtd->erasesize_mask;
 248         return do_div(sz, mtd->erasesize);
 249 }
 250
 251 static inline uint32_t mtd_div_by_ws(uint64_t sz, struct mtd_info *mtd)
 252 {
 253         if (mtd->writesize_shift)
 254                 return sz >> mtd->writesize_shift;
 255         do_div(sz, mtd->writesize);
 256         return sz;
 257 }
 258
 259 static inline uint32_t mtd_mod_by_ws(uint64_t sz, struct mtd_info *mtd)
 260 {
 261         if (mtd->writesize_shift)
 262                 return sz & mtd->writesize_mask;
 263         return do_div(sz, mtd->writesize);
 264 }
 265
 266         /* Kernel-side ioctl definitions */
 267
 268 extern int add_mtd_device(struct mtd_info *mtd);
 269 extern int del_mtd_device (struct mtd_info *mtd);
 270
 271 extern struct mtd_info *get_mtd_device(struct mtd_info *mtd, int num);
 272 extern struct mtd_info *get_mtd_device_nm(const char *name);
 273
 274 extern void put_mtd_device(struct mtd_info *mtd);
 275
 276
 277 struct mtd_notifier {
 278         void (*add)(struct mtd_info *mtd);
 279         void (*remove)(struct mtd_info *mtd);
 280         struct list_head list;
 281 };
 282
 283
 284 extern void register_mtd_user (struct mtd_notifier *new);
 285 extern int unregister_mtd_user (struct mtd_notifier *old);
 286
 287 int default_mtd_writev(struct mtd_info *mtd, const struct kvec *vecs,
 288                        unsigned long count, loff_t to, size_t *retlen);
 289
 290 int default_mtd_readv(struct mtd_info *mtd, struct kvec *vecs,
 291                       unsigned long count, loff_t from, size_t *retlen);
 292
 293 #ifdef CONFIG_MTD_PARTITIONS
 294 void mtd_erase_callback(struct erase_info *instr);
 295 #else
 296 static inline void mtd_erase_callback(struct erase_info *instr)
 297 {
 298         if (instr->callback)
 299                 instr->callback(instr);
 300 }
 301 #endif
 302
 303 /*
 304  * Debugging macro and defines
 305  */
 306 #define MTD_DEBUG_LEVEL0        (0)     /* Quiet   */
 307 #define MTD_DEBUG_LEVEL1        (1)     /* Audible */
 308 #define MTD_DEBUG_LEVEL2        (2)     /* Loud    */
 309 #define MTD_DEBUG_LEVEL3        (3)     /* Noisy   */
 310
 311 #ifdef CONFIG_MTD_DEBUG
 312 #define DEBUG(n, args...)                               \
 313         do {                                            \
 314                 if (n <= CONFIG_MTD_DEBUG_VERBOSE)      \
 315                         printk(KERN_INFO args);         \
 316         } while(0)
 317 #else /* CONFIG_MTD_DEBUG */
 318 #define DEBUG(n, args...)                               \
 319         do {                                            \
 320                 if (0)                                  \
 321                         printk(KERN_INFO args);         \
 322         } while(0)
 323
 324 #endif /* CONFIG_MTD_DEBUG */
 325
 326 #endif /* __MTD_MTD_H__ */