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 #include <linux/device.h>
  15
  16 #include <linux/mtd/compatmac.h>
  17 #include <mtd/mtd-abi.h>
  18
  19 #include <asm/div64.h>
  20
  21 #define MTD_CHAR_MAJOR 90
  22 #define MTD_BLOCK_MAJOR 31
  23 #define MAX_MTD_DEVICES 32
  24
  25 #define MTD_ERASE_PENDING       0x01
  26 #define MTD_ERASING             0x02
  27 #define MTD_ERASE_SUSPEND       0x04
  28 #define MTD_ERASE_DONE          0x08
  29 #define MTD_ERASE_FAILED        0x10
  30
  31 #define MTD_FAIL_ADDR_UNKNOWN -1LL
  32
  33 /* If the erase fails, fail_addr might indicate exactly which block failed.  If
  34    fail_addr = MTD_FAIL_ADDR_UNKNOWN, the failure was not at the device level or was not
  35    specific to any particular block. */
  36 struct erase_info {
  37         struct mtd_info *mtd;
  38         uint64_t addr;
  39         uint64_t len;
  40         uint64_t fail_addr;
  41         u_long time;
  42         u_long retries;
  43         unsigned dev;
  44         unsigned cell;
  45         void (*callback) (struct erase_info *self);
  46         u_long priv;
  47         u_char state;
  48         struct erase_info *next;
  49 };
  50
  51 struct mtd_erase_region_info {
  52         uint64_t offset;                        /* At which this region starts, from the beginning of the MTD */
  53         uint32_t erasesize;             /* For this region */
  54         uint32_t numblocks;             /* Number of blocks of erasesize in this region */
  55         unsigned long *lockmap;         /* If keeping bitmap of locks */
  56 };
  57
  58 /*
  59  * oob operation modes
  60  *
  61  * MTD_OOB_PLACE:       oob data are placed at the given offset
  62  * MTD_OOB_AUTO:        oob data are automatically placed at the free areas
  63  *                      which are defined by the ecclayout
  64  * MTD_OOB_RAW:         mode to read raw data+oob in one chunk. The oob data
  65  *                      is inserted into the data. Thats a raw image of the
  66  *                      flash contents.
  67  */
  68 typedef enum {
  69         MTD_OOB_PLACE,
  70         MTD_OOB_AUTO,
  71         MTD_OOB_RAW,
  72 } mtd_oob_mode_t;
  73
  74 /**
  75  * struct mtd_oob_ops - oob operation operands
  76  * @mode:       operation mode
  77  *
  78  * @len:        number of data bytes to write/read
  79  *
  80  * @retlen:     number of data bytes written/read
  81  *
  82  * @ooblen:     number of oob bytes to write/read
  83  * @oobretlen:  number of oob bytes written/read
  84  * @ooboffs:    offset of oob data in the oob area (only relevant when
  85  *              mode = MTD_OOB_PLACE)
  86  * @datbuf:     data buffer - if NULL only oob data are read/written
  87  * @oobbuf:     oob data buffer
  88  *
  89  * Note, it is allowed to read more than one OOB area at one go, but not write.
  90  * The interface assumes that the OOB write requests program only one page's
  91  * OOB area.
  92  */
  93 struct mtd_oob_ops {
  94         mtd_oob_mode_t  mode;
  95         size_t          len;
  96         size_t          retlen;
  97         size_t          ooblen;
  98         size_t          oobretlen;
  99         uint32_t        ooboffs;
 100         uint8_t         *datbuf;
 101         uint8_t         *oobbuf;
 102 };
 103
 104 struct mtd_info {
 105         u_char type;
 106         uint32_t flags;
 107         uint64_t size;   // Total size of the MTD
 108
 109         /* "Major" erase size for the device. Naïve users may take this
 110          * to be the only erase size available, or may use the more detailed
 111          * information below if they desire
 112          */
 113         uint32_t erasesize;
 114         /* Minimal writable flash unit size. In case of NOR flash it is 1 (even
 115          * though individual bits can be cleared), in case of NAND flash it is
 116          * one NAND page (or half, or one-fourths of it), in case of ECC-ed NOR
 117          * it is of ECC block size, etc. It is illegal to have writesize = 0.
 118          * Any driver registering a struct mtd_info must ensure a writesize of
 119          * 1 or larger.
 120          */
 121         uint32_t writesize;
 122
 123         uint32_t oobsize;   // Amount of OOB data per block (e.g. 16)
 124         uint32_t oobavail;  // Available OOB bytes per block
 125
 126         /*
 127          * If erasesize is a power of 2 then the shift is stored in
 128          * erasesize_shift otherwise erasesize_shift is zero. Ditto writesize.
 129          */
 130         unsigned int erasesize_shift;
 131         unsigned int writesize_shift;
 132         /* Masks based on erasesize_shift and writesize_shift */
 133         unsigned int erasesize_mask;
 134         unsigned int writesize_mask;
 135
 136         // Kernel-only stuff starts here.
 137         const char *name;
 138         int index;
 139
 140         /* ecc layout structure pointer - read only ! */
 141         struct nand_ecclayout *ecclayout;
 142
 143         /* Data for variable erase regions. If numeraseregions is zero,
 144          * it means that the whole device has erasesize as given above.
 145          */
 146         int numeraseregions;
 147         struct mtd_erase_region_info *eraseregions;
 148
 149         /*
 150          * Erase is an asynchronous operation.  Device drivers are supposed
 151          * to call instr->callback() whenever the operation completes, even
 152          * if it completes with a failure.
 153          * Callers are supposed to pass a callback function and wait for it
 154          * to be called before writing to the block.
 155          */
 156         int (*erase) (struct mtd_info *mtd, struct erase_info *instr);
 157
 158         /* This stuff for eXecute-In-Place */
 159         /* phys is optional and may be set to NULL */
 160         int (*point) (struct mtd_info *mtd, loff_t from, size_t len,
 161                         size_t *retlen, void **virt, resource_size_t *phys);
 162
 163         /* We probably shouldn't allow XIP if the unpoint isn't a NULL */
 164         void (*unpoint) (struct mtd_info *mtd, loff_t from, size_t len);
 165
 166         /* Allow NOMMU mmap() to directly map the device (if not NULL)
 167          * - return the address to which the offset maps
 168          * - return -ENOSYS to indicate refusal to do the mapping
 169          */
 170         unsigned long (*get_unmapped_area) (struct mtd_info *mtd,
 171                                             unsigned long len,
 172                                             unsigned long offset,
 173                                             unsigned long flags);
 174
 175         /* Backing device capabilities for this device
 176          * - provides mmap capabilities
 177          */
 178         struct backing_dev_info *backing_dev_info;
 179
 180
 181         int (*read) (struct mtd_info *mtd, loff_t from, size_t len, size_t *retlen, u_char *buf);
 182         int (*write) (struct mtd_info *mtd, loff_t to, size_t len, size_t *retlen, const u_char *buf);
 183
 184         /* In blackbox flight recorder like scenarios we want to make successful
 185            writes in interrupt context. panic_write() is only intended to be
 186            called when its known the kernel is about to panic and we need the
 187            write to succeed. Since the kernel is not going to be running for much
 188            longer, this function can break locks and delay to ensure the write
 189            succeeds (but not sleep). */
 190
 191         int (*panic_write) (struct mtd_info *mtd, loff_t to, size_t len, size_t *retlen, const u_char *buf);
 192
 193         int (*read_oob) (struct mtd_info *mtd, loff_t from,
 194                          struct mtd_oob_ops *ops);
 195         int (*write_oob) (struct mtd_info *mtd, loff_t to,
 196                          struct mtd_oob_ops *ops);
 197
 198         /*
 199          * Methods to access the protection register area, present in some
 200          * flash devices. The user data is one time programmable but the
 201          * factory data is read only.
 202          */
 203         int (*get_fact_prot_info) (struct mtd_info *mtd, struct otp_info *buf, size_t len);
 204         int (*read_fact_prot_reg) (struct mtd_info *mtd, loff_t from, size_t len, size_t *retlen, u_char *buf);
 205         int (*get_user_prot_info) (struct mtd_info *mtd, struct otp_info *buf, size_t len);
 206         int (*read_user_prot_reg) (struct mtd_info *mtd, loff_t from, size_t len, size_t *retlen, u_char *buf);
 207         int (*write_user_prot_reg) (struct mtd_info *mtd, loff_t from, size_t len, size_t *retlen, u_char *buf);
 208         int (*lock_user_prot_reg) (struct mtd_info *mtd, loff_t from, size_t len);
 209
 210         /* kvec-based read/write methods.
 211            NB: The 'count' parameter is the number of _vectors_, each of
 212            which contains an (ofs, len) tuple.
 213         */
 214         int (*writev) (struct mtd_info *mtd, const struct kvec *vecs, unsigned long count, loff_t to, size_t *retlen);
 215
 216         /* Sync */
 217         void (*sync) (struct mtd_info *mtd);
 218
 219         /* Chip-supported device locking */
 220         int (*lock) (struct mtd_info *mtd, loff_t ofs, uint64_t len);
 221         int (*unlock) (struct mtd_info *mtd, loff_t ofs, uint64_t len);
 222
 223         /* Power Management functions */
 224         int (*suspend) (struct mtd_info *mtd);
 225         void (*resume) (struct mtd_info *mtd);
 226
 227         /* Bad block management functions */
 228         int (*block_isbad) (struct mtd_info *mtd, loff_t ofs);
 229         int (*block_markbad) (struct mtd_info *mtd, loff_t ofs);
 230
 231         struct notifier_block reboot_notifier;  /* default mode before reboot */
 232
 233         /* ECC status information */
 234         struct mtd_ecc_stats ecc_stats;
 235         /* Subpage shift (NAND) */
 236         int subpage_sft;
 237
 238         void *priv;
 239
 240         struct module *owner;
 241         struct device dev;
 242         int usecount;
 243
 244         /* If the driver is something smart, like UBI, it may need to maintain
 245          * its own reference counting. The below functions are only for driver.
 246          * The driver may register its callbacks. These callbacks are not
 247          * supposed to be called by MTD users */
 248         int (*get_device) (struct mtd_info *mtd);
 249         void (*put_device) (struct mtd_info *mtd);
 250 };
 251
 252 static inline struct mtd_info *dev_to_mtd(struct device *dev)
 253 {
 254         return dev ? dev_get_drvdata(dev) : NULL;
 255 }
 256
 257 static inline uint32_t mtd_div_by_eb(uint64_t sz, struct mtd_info *mtd)
 258 {
 259         if (mtd->erasesize_shift)
 260                 return sz >> mtd->erasesize_shift;
 261         do_div(sz, mtd->erasesize);
 262         return sz;
 263 }
 264
 265 static inline uint32_t mtd_mod_by_eb(uint64_t sz, struct mtd_info *mtd)
 266 {
 267         if (mtd->erasesize_shift)
 268                 return sz & mtd->erasesize_mask;
 269         return do_div(sz, mtd->erasesize);
 270 }
 271
 272 static inline uint32_t mtd_div_by_ws(uint64_t sz, struct mtd_info *mtd)
 273 {
 274         if (mtd->writesize_shift)
 275                 return sz >> mtd->writesize_shift;
 276         do_div(sz, mtd->writesize);
 277         return sz;
 278 }
 279
 280 static inline uint32_t mtd_mod_by_ws(uint64_t sz, struct mtd_info *mtd)
 281 {
 282         if (mtd->writesize_shift)
 283                 return sz & mtd->writesize_mask;
 284         return do_div(sz, mtd->writesize);
 285 }
 286
 287         /* Kernel-side ioctl definitions */
 288
 289 extern int add_mtd_device(struct mtd_info *mtd);
 290 extern int del_mtd_device (struct mtd_info *mtd);
 291
 292 extern struct mtd_info *get_mtd_device(struct mtd_info *mtd, int num);
 293 extern struct mtd_info *get_mtd_device_nm(const char *name);
 294
 295 extern void put_mtd_device(struct mtd_info *mtd);
 296
 297
 298 struct mtd_notifier {
 299         void (*add)(struct mtd_info *mtd);
 300         void (*remove)(struct mtd_info *mtd);
 301         struct list_head list;
 302 };
 303
 304
 305 extern void register_mtd_user (struct mtd_notifier *new);
 306 extern int unregister_mtd_user (struct mtd_notifier *old);
 307
 308 int default_mtd_writev(struct mtd_info *mtd, const struct kvec *vecs,
 309                        unsigned long count, loff_t to, size_t *retlen);
 310
 311 int default_mtd_readv(struct mtd_info *mtd, struct kvec *vecs,
 312                       unsigned long count, loff_t from, size_t *retlen);
 313
 314 #ifdef CONFIG_MTD_PARTITIONS
 315 void mtd_erase_callback(struct erase_info *instr);
 316 #else
 317 static inline void mtd_erase_callback(struct erase_info *instr)
 318 {
 319         if (instr->callback)
 320                 instr->callback(instr);
 321 }
 322 #endif
 323
 324 /*
 325  * Debugging macro and defines
 326  */
 327 #define MTD_DEBUG_LEVEL0        (0)     /* Quiet   */
 328 #define MTD_DEBUG_LEVEL1        (1)     /* Audible */
 329 #define MTD_DEBUG_LEVEL2        (2)     /* Loud    */
 330 #define MTD_DEBUG_LEVEL3        (3)     /* Noisy   */
 331
 332 #ifdef CONFIG_MTD_DEBUG
 333 #define DEBUG(n, args...)                               \
 334         do {                                            \
 335                 if (n <= CONFIG_MTD_DEBUG_VERBOSE)      \
 336                         printk(KERN_INFO args);         \
 337         } while(0)
 338 #else /* CONFIG_MTD_DEBUG */
 339 #define DEBUG(n, args...)                               \
 340         do {                                            \
 341                 if (0)                                  \
 342                         printk(KERN_INFO args);         \
 343         } while(0)
 344
 345 #endif /* CONFIG_MTD_DEBUG */
 346
 347 #endif /* __MTD_MTD_H__ */