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 oob and data without doing ECC checking
  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 than 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         uint32_t flags;
 104         uint64_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         uint32_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         uint32_t writesize;
 119
 120         uint32_t oobsize;   // Amount of OOB data per block (e.g. 16)
 121         uint32_t oobavail;  // Available OOB bytes per block
 122
 123         /*
 124          * If erasesize is a power of 2 then the shift is stored in
 125          * erasesize_shift otherwise erasesize_shift is zero. Ditto writesize.
 126          */
 127         unsigned int erasesize_shift;
 128         unsigned int writesize_shift;
 129         /* Masks based on erasesize_shift and writesize_shift */
 130         unsigned int erasesize_mask;
 131         unsigned int writesize_mask;
 132
 133         // Kernel-only stuff starts here.
 134         const char *name;
 135         int index;
 136
 137         /* ecc layout structure pointer - read only ! */
 138         struct nand_ecclayout *ecclayout;
 139
 140         /* Data for variable erase regions. If numeraseregions is zero,
 141          * it means that the whole device has erasesize as given above.
 142          */
 143         int numeraseregions;
 144         struct mtd_erase_region_info *eraseregions;
 145
 146         /*
 147          * Erase is an asynchronous operation.  Device drivers are supposed
 148          * to call instr->callback() whenever the operation completes, even
 149          * if it completes with a failure.
 150          * Callers are supposed to pass a callback function and wait for it
 151          * to be called before writing to the block.
 152          */
 153         int (*erase) (struct mtd_info *mtd, struct erase_info *instr);
 154
 155         /* This stuff for eXecute-In-Place */
 156         /* phys is optional and may be set to NULL */
 157         int (*point) (struct mtd_info *mtd, loff_t from, size_t len,
 158                         size_t *retlen, void **virt, resource_size_t *phys);
 159
 160         /* We probably shouldn't allow XIP if the unpoint isn't a NULL */
 161         void (*unpoint) (struct mtd_info *mtd, loff_t from, size_t len);
 162
 163         /* Allow NOMMU mmap() to directly map the device (if not NULL)
 164          * - return the address to which the offset maps
 165          * - return -ENOSYS to indicate refusal to do the mapping
 166          */
 167         unsigned long (*get_unmapped_area) (struct mtd_info *mtd,
 168                                             unsigned long len,
 169                                             unsigned long offset,
 170                                             unsigned long flags);
 171
 172         /* Backing device capabilities for this device
 173          * - provides mmap capabilities
 174          */
 175         struct backing_dev_info *backing_dev_info;
 176
 177
 178         int (*read) (struct mtd_info *mtd, loff_t from, size_t len, size_t *retlen, u_char *buf);
 179         int (*write) (struct mtd_info *mtd, loff_t to, size_t len, size_t *retlen, const u_char *buf);
 180
 181         /* In blackbox flight recorder like scenarios we want to make successful
 182            writes in interrupt context. panic_write() is only intended to be
 183            called when its known the kernel is about to panic and we need the
 184            write to succeed. Since the kernel is not going to be running for much
 185            longer, this function can break locks and delay to ensure the write
 186            succeeds (but not sleep). */
 187
 188         int (*panic_write) (struct mtd_info *mtd, loff_t to, size_t len, size_t *retlen, const u_char *buf);
 189
 190         int (*read_oob) (struct mtd_info *mtd, loff_t from,
 191                          struct mtd_oob_ops *ops);
 192         int (*write_oob) (struct mtd_info *mtd, loff_t to,
 193                          struct mtd_oob_ops *ops);
 194
 195         /*
 196          * Methods to access the protection register area, present in some
 197          * flash devices. The user data is one time programmable but the
 198          * factory data is read only.
 199          */
 200         int (*get_fact_prot_info) (struct mtd_info *mtd, struct otp_info *buf, size_t len);
 201         int (*read_fact_prot_reg) (struct mtd_info *mtd, loff_t from, size_t len, size_t *retlen, u_char *buf);
 202         int (*get_user_prot_info) (struct mtd_info *mtd, struct otp_info *buf, size_t len);
 203         int (*read_user_prot_reg) (struct mtd_info *mtd, loff_t from, size_t len, size_t *retlen, u_char *buf);
 204         int (*write_user_prot_reg) (struct mtd_info *mtd, loff_t from, size_t len, size_t *retlen, u_char *buf);
 205         int (*lock_user_prot_reg) (struct mtd_info *mtd, loff_t from, size_t len);
 206
 207         /* kvec-based read/write methods.
 208            NB: The 'count' parameter is the number of _vectors_, each of
 209            which contains an (ofs, len) tuple.
 210         */
 211         int (*writev) (struct mtd_info *mtd, const struct kvec *vecs, unsigned long count, loff_t to, size_t *retlen);
 212
 213         /* Sync */
 214         void (*sync) (struct mtd_info *mtd);
 215
 216         /* Chip-supported device locking */
 217         int (*lock) (struct mtd_info *mtd, loff_t ofs, uint64_t len);
 218         int (*unlock) (struct mtd_info *mtd, loff_t ofs, uint64_t len);
 219
 220         /* Power Management functions */
 221         int (*suspend) (struct mtd_info *mtd);
 222         void (*resume) (struct mtd_info *mtd);
 223
 224         /* Bad block management functions */
 225         int (*block_isbad) (struct mtd_info *mtd, loff_t ofs);
 226         int (*block_markbad) (struct mtd_info *mtd, loff_t ofs);
 227
 228         struct notifier_block reboot_notifier;  /* default mode before reboot */
 229
 230         /* ECC status information */
 231         struct mtd_ecc_stats ecc_stats;
 232         /* Subpage shift (NAND) */
 233         int subpage_sft;
 234
 235         void *priv;
 236
 237         struct module *owner;
 238         struct device dev;
 239         int usecount;
 240
 241         /* If the driver is something smart, like UBI, it may need to maintain
 242          * its own reference counting. The below functions are only for driver.
 243          * The driver may register its callbacks. These callbacks are not
 244          * supposed to be called by MTD users */
 245         int (*get_device) (struct mtd_info *mtd);
 246         void (*put_device) (struct mtd_info *mtd);
 247 };
 248
 249 static inline struct mtd_info *dev_to_mtd(struct device *dev)
 250 {
 251         return dev ? dev_get_drvdata(dev) : NULL;
 252 }
 253
 254 static inline uint32_t mtd_div_by_eb(uint64_t sz, struct mtd_info *mtd)
 255 {
 256         if (mtd->erasesize_shift)
 257                 return sz >> mtd->erasesize_shift;
 258         do_div(sz, mtd->erasesize);
 259         return sz;
 260 }
 261
 262 static inline uint32_t mtd_mod_by_eb(uint64_t sz, struct mtd_info *mtd)
 263 {
 264         if (mtd->erasesize_shift)
 265                 return sz & mtd->erasesize_mask;
 266         return do_div(sz, mtd->erasesize);
 267 }
 268
 269 static inline uint32_t mtd_div_by_ws(uint64_t sz, struct mtd_info *mtd)
 270 {
 271         if (mtd->writesize_shift)
 272                 return sz >> mtd->writesize_shift;
 273         do_div(sz, mtd->writesize);
 274         return sz;
 275 }
 276
 277 static inline uint32_t mtd_mod_by_ws(uint64_t sz, struct mtd_info *mtd)
 278 {
 279         if (mtd->writesize_shift)
 280                 return sz & mtd->writesize_mask;
 281         return do_div(sz, mtd->writesize);
 282 }
 283
 284         /* Kernel-side ioctl definitions */
 285
 286 extern int add_mtd_device(struct mtd_info *mtd);
 287 extern int del_mtd_device (struct mtd_info *mtd);
 288
 289 extern struct mtd_info *get_mtd_device(struct mtd_info *mtd, int num);
 290 extern int __get_mtd_device(struct mtd_info *mtd);
 291 extern void __put_mtd_device(struct mtd_info *mtd);
 292 extern struct mtd_info *get_mtd_device_nm(const char *name);
 293 extern void put_mtd_device(struct mtd_info *mtd);
 294
 295
 296 struct mtd_notifier {
 297         void (*add)(struct mtd_info *mtd);
 298         void (*remove)(struct mtd_info *mtd);
 299         struct list_head list;
 300 };
 301
 302
 303 extern void register_mtd_user (struct mtd_notifier *new);
 304 extern int unregister_mtd_user (struct mtd_notifier *old);
 305
 306 int default_mtd_writev(struct mtd_info *mtd, const struct kvec *vecs,
 307                        unsigned long count, loff_t to, size_t *retlen);
 308
 309 int default_mtd_readv(struct mtd_info *mtd, struct kvec *vecs,
 310                       unsigned long count, loff_t from, size_t *retlen);
 311
 312 #ifdef CONFIG_MTD_PARTITIONS
 313 void mtd_erase_callback(struct erase_info *instr);
 314 #else
 315 static inline void mtd_erase_callback(struct erase_info *instr)
 316 {
 317         if (instr->callback)
 318                 instr->callback(instr);
 319 }
 320 #endif
 321
 322 /*
 323  * Debugging macro and defines
 324  */
 325 #define MTD_DEBUG_LEVEL0        (0)     /* Quiet   */
 326 #define MTD_DEBUG_LEVEL1        (1)     /* Audible */
 327 #define MTD_DEBUG_LEVEL2        (2)     /* Loud    */
 328 #define MTD_DEBUG_LEVEL3        (3)     /* Noisy   */
 329
 330 #ifdef CONFIG_MTD_DEBUG
 331 #define DEBUG(n, args...)                               \
 332         do {                                            \
 333                 if (n <= CONFIG_MTD_DEBUG_VERBOSE)      \
 334                         printk(KERN_INFO args);         \
 335         } while(0)
 336 #else /* CONFIG_MTD_DEBUG */
 337 #define DEBUG(n, args...)                               \
 338         do {                                            \
 339                 if (0)                                  \
 340                         printk(KERN_INFO args);         \
 341         } while(0)
 342
 343 #endif /* CONFIG_MTD_DEBUG */
 344
 345 #endif /* __MTD_MTD_H__ */