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
  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         /* Allow NOMMU mmap() to directly map the device (if not NULL)
 166          * - return the address to which the offset maps
 167          * - return -ENOSYS to indicate refusal to do the mapping
 168          */
 169         unsigned long (*get_unmapped_area) (struct mtd_info *mtd,
 170                                             unsigned long len,
 171                                             unsigned long offset,
 172                                             unsigned long flags);
 173
 174         /* Backing device capabilities for this device
 175          * - provides mmap capabilities
 176          */
 177         struct backing_dev_info *backing_dev_info;
 178
 179
 180         int (*read) (struct mtd_info *mtd, loff_t from, size_t len, size_t *retlen, u_char *buf);
 181         int (*write) (struct mtd_info *mtd, loff_t to, size_t len, size_t *retlen, const u_char *buf);
 182
 183         /* In blackbox flight recorder like scenarios we want to make successful
 184            writes in interrupt context. panic_write() is only intended to be
 185            called when its known the kernel is about to panic and we need the
 186            write to succeed. Since the kernel is not going to be running for much
 187            longer, this function can break locks and delay to ensure the write
 188            succeeds (but not sleep). */
 189
 190         int (*panic_write) (struct mtd_info *mtd, loff_t to, size_t len, size_t *retlen, const u_char *buf);
 191
 192         int (*read_oob) (struct mtd_info *mtd, loff_t from,
 193                          struct mtd_oob_ops *ops);
 194         int (*write_oob) (struct mtd_info *mtd, loff_t to,
 195                          struct mtd_oob_ops *ops);
 196
 197         /*
 198          * Methods to access the protection register area, present in some
 199          * flash devices. The user data is one time programmable but the
 200          * factory data is read only.
 201          */
 202         int (*get_fact_prot_info) (struct mtd_info *mtd, struct otp_info *buf, size_t len);
 203         int (*read_fact_prot_reg) (struct mtd_info *mtd, loff_t from, size_t len, size_t *retlen, u_char *buf);
 204         int (*get_user_prot_info) (struct mtd_info *mtd, struct otp_info *buf, size_t len);
 205         int (*read_user_prot_reg) (struct mtd_info *mtd, loff_t from, size_t len, size_t *retlen, u_char *buf);
 206         int (*write_user_prot_reg) (struct mtd_info *mtd, loff_t from, size_t len, size_t *retlen, u_char *buf);
 207         int (*lock_user_prot_reg) (struct mtd_info *mtd, loff_t from, size_t len);
 208
 209         /* kvec-based read/write methods.
 210            NB: The 'count' parameter is the number of _vectors_, each of
 211            which contains an (ofs, len) tuple.
 212         */
 213         int (*writev) (struct mtd_info *mtd, const struct kvec *vecs, unsigned long count, loff_t to, size_t *retlen);
 214
 215         /* Sync */
 216         void (*sync) (struct mtd_info *mtd);
 217
 218         /* Chip-supported device locking */
 219         int (*lock) (struct mtd_info *mtd, loff_t ofs, uint64_t len);
 220         int (*unlock) (struct mtd_info *mtd, loff_t ofs, uint64_t len);
 221
 222         /* Power Management functions */
 223         int (*suspend) (struct mtd_info *mtd);
 224         void (*resume) (struct mtd_info *mtd);
 225
 226         /* Bad block management functions */
 227         int (*block_isbad) (struct mtd_info *mtd, loff_t ofs);
 228         int (*block_markbad) (struct mtd_info *mtd, loff_t ofs);
 229
 230         struct notifier_block reboot_notifier;  /* default mode before reboot */
 231
 232         /* ECC status information */
 233         struct mtd_ecc_stats ecc_stats;
 234         /* Subpage shift (NAND) */
 235         int subpage_sft;
 236
 237         void *priv;
 238
 239         struct module *owner;
 240         struct device dev;
 241         int usecount;
 242
 243         /* If the driver is something smart, like UBI, it may need to maintain
 244          * its own reference counting. The below functions are only for driver.
 245          * The driver may register its callbacks. These callbacks are not
 246          * supposed to be called by MTD users */
 247         int (*get_device) (struct mtd_info *mtd);
 248         void (*put_device) (struct mtd_info *mtd);
 249 };
 250
 251 static inline struct mtd_info *dev_to_mtd(struct device *dev)
 252 {
 253         return dev ? dev_get_drvdata(dev) : NULL;
 254 }
 255
 256 static inline uint32_t mtd_div_by_eb(uint64_t sz, struct mtd_info *mtd)
 257 {
 258         if (mtd->erasesize_shift)
 259                 return sz >> mtd->erasesize_shift;
 260         do_div(sz, mtd->erasesize);
 261         return sz;
 262 }
 263
 264 static inline uint32_t mtd_mod_by_eb(uint64_t sz, struct mtd_info *mtd)
 265 {
 266         if (mtd->erasesize_shift)
 267                 return sz & mtd->erasesize_mask;
 268         return do_div(sz, mtd->erasesize);
 269 }
 270
 271 static inline uint32_t mtd_div_by_ws(uint64_t sz, struct mtd_info *mtd)
 272 {
 273         if (mtd->writesize_shift)
 274                 return sz >> mtd->writesize_shift;
 275         do_div(sz, mtd->writesize);
 276         return sz;
 277 }
 278
 279 static inline uint32_t mtd_mod_by_ws(uint64_t sz, struct mtd_info *mtd)
 280 {
 281         if (mtd->writesize_shift)
 282                 return sz & mtd->writesize_mask;
 283         return do_div(sz, mtd->writesize);
 284 }
 285
 286         /* Kernel-side ioctl definitions */
 287
 288 extern int add_mtd_device(struct mtd_info *mtd);
 289 extern int del_mtd_device (struct mtd_info *mtd);
 290
 291 extern struct mtd_info *get_mtd_device(struct mtd_info *mtd, int num);
 292 extern int __get_mtd_device(struct mtd_info *mtd);
 293 extern void __put_mtd_device(struct mtd_info *mtd);
 294 extern struct mtd_info *get_mtd_device_nm(const char *name);
 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__ */