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   1 /*
   2  * $Id: mtdchar.c,v 1.76 2005/11/07 11:14:20 gleixner Exp $
   3  *
   4  * Character-device access to raw MTD devices.
   5  *
   6  */
   7
   8 #include <linux/config.h>
   9 #include <linux/device.h>
  10 #include <linux/fs.h>
  11 #include <linux/init.h>
  12 #include <linux/kernel.h>
  13 #include <linux/module.h>
  14 #include <linux/slab.h>
  15 #include <linux/sched.h>
  16
  17 #include <linux/mtd/mtd.h>
  18 #include <linux/mtd/compatmac.h>
  19
  20 #include <asm/uaccess.h>
  21
  22 static struct class *mtd_class;
  23
  24 static void mtd_notify_add(struct mtd_info* mtd)
  25 {
  26         if (!mtd)
  27                 return;
  28
  29         class_device_create(mtd_class, NULL, MKDEV(MTD_CHAR_MAJOR, mtd->index*2),
  30                             NULL, "mtd%d", mtd->index);
  31
  32         class_device_create(mtd_class, NULL,
  33                             MKDEV(MTD_CHAR_MAJOR, mtd->index*2+1),
  34                             NULL, "mtd%dro", mtd->index);
  35 }
  36
  37 static void mtd_notify_remove(struct mtd_info* mtd)
  38 {
  39         if (!mtd)
  40                 return;
  41
  42         class_device_destroy(mtd_class, MKDEV(MTD_CHAR_MAJOR, mtd->index*2));
  43         class_device_destroy(mtd_class, MKDEV(MTD_CHAR_MAJOR, mtd->index*2+1));
  44 }
  45
  46 static struct mtd_notifier notifier = {
  47         .add    = mtd_notify_add,
  48         .remove = mtd_notify_remove,
  49 };
  50
  51 /*
  52  * We use file->private_data to store a pointer to the MTDdevice.
  53  * Since alighment is at least 32 bits, we have 2 bits free for OTP
  54  * modes as well.
  55  */
  56
  57 #define TO_MTD(file) (struct mtd_info *)((long)((file)->private_data) & ~3L)
  58
  59 #define MTD_MODE_OTP_FACT       1
  60 #define MTD_MODE_OTP_USER       2
  61 #define MTD_MODE(file)          ((long)((file)->private_data) & 3)
  62
  63 #define SET_MTD_MODE(file, mode) \
  64         do { long __p = (long)((file)->private_data); \
  65              (file)->private_data = (void *)((__p & ~3L) | mode); } while (0)
  66
  67 static loff_t mtd_lseek (struct file *file, loff_t offset, int orig)
  68 {
  69         struct mtd_info *mtd = TO_MTD(file);
  70
  71         switch (orig) {
  72         case 0:
  73                 /* SEEK_SET */
  74                 break;
  75         case 1:
  76                 /* SEEK_CUR */
  77                 offset += file->f_pos;
  78                 break;
  79         case 2:
  80                 /* SEEK_END */
  81                 offset += mtd->size;
  82                 break;
  83         default:
  84                 return -EINVAL;
  85         }
  86
  87         if (offset >= 0 && offset < mtd->size)
  88                 return file->f_pos = offset;
  89
  90         return -EINVAL;
  91 }
  92
  93
  94
  95 static int mtd_open(struct inode *inode, struct file *file)
  96 {
  97         int minor = iminor(inode);
  98         int devnum = minor >> 1;
  99         struct mtd_info *mtd;
 100
 101         DEBUG(MTD_DEBUG_LEVEL0, "MTD_open\n");
 102
 103         if (devnum >= MAX_MTD_DEVICES)
 104                 return -ENODEV;
 105
 106         /* You can't open the RO devices RW */
 107         if ((file->f_mode & 2) && (minor & 1))
 108                 return -EACCES;
 109
 110         mtd = get_mtd_device(NULL, devnum);
 111
 112         if (!mtd)
 113                 return -ENODEV;
 114
 115         if (MTD_ABSENT == mtd->type) {
 116                 put_mtd_device(mtd);
 117                 return -ENODEV;
 118         }
 119
 120         file->private_data = mtd;
 121
 122         /* You can't open it RW if it's not a writeable device */
 123         if ((file->f_mode & 2) && !(mtd->flags & MTD_WRITEABLE)) {
 124                 put_mtd_device(mtd);
 125                 return -EACCES;
 126         }
 127
 128         return 0;
 129 } /* mtd_open */
 130
 131 /*====================================================================*/
 132
 133 static int mtd_close(struct inode *inode, struct file *file)
 134 {
 135         struct mtd_info *mtd;
 136
 137         DEBUG(MTD_DEBUG_LEVEL0, "MTD_close\n");
 138
 139         mtd = TO_MTD(file);
 140
 141         if (mtd->sync)
 142                 mtd->sync(mtd);
 143
 144         put_mtd_device(mtd);
 145
 146         return 0;
 147 } /* mtd_close */
 148
 149 /* FIXME: This _really_ needs to die. In 2.5, we should lock the
 150    userspace buffer down and use it directly with readv/writev.
 151 */
 152 #define MAX_KMALLOC_SIZE 0x20000
 153
 154 static ssize_t mtd_read(struct file *file, char __user *buf, size_t count,loff_t *ppos)
 155 {
 156         struct mtd_info *mtd = TO_MTD(file);
 157         size_t retlen=0;
 158         size_t total_retlen=0;
 159         int ret=0;
 160         int len;
 161         char *kbuf;
 162
 163         DEBUG(MTD_DEBUG_LEVEL0,"MTD_read\n");
 164
 165         if (*ppos + count > mtd->size)
 166                 count = mtd->size - *ppos;
 167
 168         if (!count)
 169                 return 0;
 170
 171         /* FIXME: Use kiovec in 2.5 to lock down the user's buffers
 172            and pass them directly to the MTD functions */
 173
 174         if (count > MAX_KMALLOC_SIZE)
 175                 kbuf=kmalloc(MAX_KMALLOC_SIZE, GFP_KERNEL);
 176         else
 177                 kbuf=kmalloc(count, GFP_KERNEL);
 178
 179         if (!kbuf)
 180                 return -ENOMEM;
 181
 182         while (count) {
 183
 184                 if (count > MAX_KMALLOC_SIZE)
 185                         len = MAX_KMALLOC_SIZE;
 186                 else
 187                         len = count;
 188
 189                 switch (MTD_MODE(file)) {
 190                 case MTD_MODE_OTP_FACT:
 191                         ret = mtd->read_fact_prot_reg(mtd, *ppos, len, &retlen, kbuf);
 192                         break;
 193                 case MTD_MODE_OTP_USER:
 194                         ret = mtd->read_user_prot_reg(mtd, *ppos, len, &retlen, kbuf);
 195                         break;
 196                 default:
 197                         ret = mtd->read(mtd, *ppos, len, &retlen, kbuf);
 198                 }
 199                 /* Nand returns -EBADMSG on ecc errors, but it returns
 200                  * the data. For our userspace tools it is important
 201                  * to dump areas with ecc errors !
 202                  * For kernel internal usage it also might return -EUCLEAN
 203                  * to signal the caller that a bitflip has occured and has
 204                  * been corrected by the ECC algorithm.
 205                  * Userspace software which accesses NAND this way
 206                  * must be aware of the fact that it deals with NAND
 207                  */
 208                 if (!ret || (ret == -EUCLEAN) || (ret == -EBADMSG)) {
 209                         *ppos += retlen;
 210                         if (copy_to_user(buf, kbuf, retlen)) {
 211                                 kfree(kbuf);
 212                                 return -EFAULT;
 213                         }
 214                         else
 215                                 total_retlen += retlen;
 216
 217                         count -= retlen;
 218                         buf += retlen;
 219                         if (retlen == 0)
 220                                 count = 0;
 221                 }
 222                 else {
 223                         kfree(kbuf);
 224                         return ret;
 225                 }
 226
 227         }
 228
 229         kfree(kbuf);
 230         return total_retlen;
 231 } /* mtd_read */
 232
 233 static ssize_t mtd_write(struct file *file, const char __user *buf, size_t count,loff_t *ppos)
 234 {
 235         struct mtd_info *mtd = TO_MTD(file);
 236         char *kbuf;
 237         size_t retlen;
 238         size_t total_retlen=0;
 239         int ret=0;
 240         int len;
 241
 242         DEBUG(MTD_DEBUG_LEVEL0,"MTD_write\n");
 243
 244         if (*ppos == mtd->size)
 245                 return -ENOSPC;
 246
 247         if (*ppos + count > mtd->size)
 248                 count = mtd->size - *ppos;
 249
 250         if (!count)
 251                 return 0;
 252
 253         if (count > MAX_KMALLOC_SIZE)
 254                 kbuf=kmalloc(MAX_KMALLOC_SIZE, GFP_KERNEL);
 255         else
 256                 kbuf=kmalloc(count, GFP_KERNEL);
 257
 258         if (!kbuf)
 259                 return -ENOMEM;
 260
 261         while (count) {
 262
 263                 if (count > MAX_KMALLOC_SIZE)
 264                         len = MAX_KMALLOC_SIZE;
 265                 else
 266                         len = count;
 267
 268                 if (copy_from_user(kbuf, buf, len)) {
 269                         kfree(kbuf);
 270                         return -EFAULT;
 271                 }
 272
 273                 switch (MTD_MODE(file)) {
 274                 case MTD_MODE_OTP_FACT:
 275                         ret = -EROFS;
 276                         break;
 277                 case MTD_MODE_OTP_USER:
 278                         if (!mtd->write_user_prot_reg) {
 279                                 ret = -EOPNOTSUPP;
 280                                 break;
 281                         }
 282                         ret = mtd->write_user_prot_reg(mtd, *ppos, len, &retlen, kbuf);
 283                         break;
 284                 default:
 285                         ret = (*(mtd->write))(mtd, *ppos, len, &retlen, kbuf);
 286                 }
 287                 if (!ret) {
 288                         *ppos += retlen;
 289                         total_retlen += retlen;
 290                         count -= retlen;
 291                         buf += retlen;
 292                 }
 293                 else {
 294                         kfree(kbuf);
 295                         return ret;
 296                 }
 297         }
 298
 299         kfree(kbuf);
 300         return total_retlen;
 301 } /* mtd_write */
 302
 303 /*======================================================================
 304
 305     IOCTL calls for getting device parameters.
 306
 307 ======================================================================*/
 308 static void mtdchar_erase_callback (struct erase_info *instr)
 309 {
 310         wake_up((wait_queue_head_t *)instr->priv);
 311 }
 312
 313 static int mtd_ioctl(struct inode *inode, struct file *file,
 314                      u_int cmd, u_long arg)
 315 {
 316         struct mtd_info *mtd = TO_MTD(file);
 317         void __user *argp = (void __user *)arg;
 318         int ret = 0;
 319         u_long size;
 320
 321         DEBUG(MTD_DEBUG_LEVEL0, "MTD_ioctl\n");
 322
 323         size = (cmd & IOCSIZE_MASK) >> IOCSIZE_SHIFT;
 324         if (cmd & IOC_IN) {
 325                 if (!access_ok(VERIFY_READ, argp, size))
 326                         return -EFAULT;
 327         }
 328         if (cmd & IOC_OUT) {
 329                 if (!access_ok(VERIFY_WRITE, argp, size))
 330                         return -EFAULT;
 331         }
 332
 333         switch (cmd) {
 334         case MEMGETREGIONCOUNT:
 335                 if (copy_to_user(argp, &(mtd->numeraseregions), sizeof(int)))
 336                         return -EFAULT;
 337                 break;
 338
 339         case MEMGETREGIONINFO:
 340         {
 341                 struct region_info_user ur;
 342
 343                 if (copy_from_user(&ur, argp, sizeof(struct region_info_user)))
 344                         return -EFAULT;
 345
 346                 if (ur.regionindex >= mtd->numeraseregions)
 347                         return -EINVAL;
 348                 if (copy_to_user(argp, &(mtd->eraseregions[ur.regionindex]),
 349                                 sizeof(struct mtd_erase_region_info)))
 350                         return -EFAULT;
 351                 break;
 352         }
 353
 354         case MEMGETINFO:
 355                 if (copy_to_user(argp, mtd, sizeof(struct mtd_info_user)))
 356                         return -EFAULT;
 357                 break;
 358
 359         case MEMERASE:
 360         {
 361                 struct erase_info *erase;
 362
 363                 if(!(file->f_mode & 2))
 364                         return -EPERM;
 365
 366                 erase=kmalloc(sizeof(struct erase_info),GFP_KERNEL);
 367                 if (!erase)
 368                         ret = -ENOMEM;
 369                 else {
 370                         wait_queue_head_t waitq;
 371                         DECLARE_WAITQUEUE(wait, current);
 372
 373                         init_waitqueue_head(&waitq);
 374
 375                         memset (erase,0,sizeof(struct erase_info));
 376                         if (copy_from_user(&erase->addr, argp,
 377                                     sizeof(struct erase_info_user))) {
 378                                 kfree(erase);
 379                                 return -EFAULT;
 380                         }
 381                         erase->mtd = mtd;
 382                         erase->callback = mtdchar_erase_callback;
 383                         erase->priv = (unsigned long)&waitq;
 384
 385                         /*
 386                           FIXME: Allow INTERRUPTIBLE. Which means
 387                           not having the wait_queue head on the stack.
 388
 389                           If the wq_head is on the stack, and we
 390                           leave because we got interrupted, then the
 391                           wq_head is no longer there when the
 392                           callback routine tries to wake us up.
 393                         */
 394                         ret = mtd->erase(mtd, erase);
 395                         if (!ret) {
 396                                 set_current_state(TASK_UNINTERRUPTIBLE);
 397                                 add_wait_queue(&waitq, &wait);
 398                                 if (erase->state != MTD_ERASE_DONE &&
 399                                     erase->state != MTD_ERASE_FAILED)
 400                                         schedule();
 401                                 remove_wait_queue(&waitq, &wait);
 402                                 set_current_state(TASK_RUNNING);
 403
 404                                 ret = (erase->state == MTD_ERASE_FAILED)?-EIO:0;
 405                         }
 406                         kfree(erase);
 407                 }
 408                 break;
 409         }
 410
 411         case MEMWRITEOOB:
 412         {
 413                 struct mtd_oob_buf buf;
 414                 struct mtd_oob_ops ops;
 415
 416                 if(!(file->f_mode & 2))
 417                         return -EPERM;
 418
 419                 if (copy_from_user(&buf, argp, sizeof(struct mtd_oob_buf)))
 420                         return -EFAULT;
 421
 422                 if (buf.length > 4096)
 423                         return -EINVAL;
 424
 425                 if (!mtd->write_oob)
 426                         ret = -EOPNOTSUPP;
 427                 else
 428                         ret = access_ok(VERIFY_READ, buf.ptr,
 429                                         buf.length) ? 0 : EFAULT;
 430
 431                 if (ret)
 432                         return ret;
 433
 434                 ops.len = buf.length;
 435                 ops.ooblen = mtd->oobsize;
 436                 ops.ooboffs = buf.start & (mtd->oobsize - 1);
 437                 ops.datbuf = NULL;
 438                 ops.mode = MTD_OOB_PLACE;
 439
 440                 if (ops.ooboffs && ops.len > (ops.ooblen - ops.ooboffs))
 441                         return -EINVAL;
 442
 443                 ops.oobbuf = kmalloc(buf.length, GFP_KERNEL);
 444                 if (!ops.oobbuf)
 445                         return -ENOMEM;
 446
 447                 if (copy_from_user(ops.oobbuf, buf.ptr, buf.length)) {
 448                         kfree(ops.oobbuf);
 449                         return -EFAULT;
 450                 }
 451
 452                 buf.start &= ~(mtd->oobsize - 1);
 453                 ret = mtd->write_oob(mtd, buf.start, &ops);
 454
 455                 if (copy_to_user(argp + sizeof(uint32_t), &ops.retlen,
 456                                  sizeof(uint32_t)))
 457                         ret = -EFAULT;
 458
 459                 kfree(ops.oobbuf);
 460                 break;
 461
 462         }
 463
 464         case MEMREADOOB:
 465         {
 466                 struct mtd_oob_buf buf;
 467                 struct mtd_oob_ops ops;
 468
 469                 if (copy_from_user(&buf, argp, sizeof(struct mtd_oob_buf)))
 470                         return -EFAULT;
 471
 472                 if (buf.length > 4096)
 473                         return -EINVAL;
 474
 475                 if (!mtd->read_oob)
 476                         ret = -EOPNOTSUPP;
 477                 else
 478                         ret = access_ok(VERIFY_WRITE, buf.ptr,
 479                                         buf.length) ? 0 : -EFAULT;
 480                 if (ret)
 481                         return ret;
 482
 483                 ops.len = buf.length;
 484                 ops.ooblen = mtd->oobsize;
 485                 ops.ooboffs = buf.start & (mtd->oobsize - 1);
 486                 ops.datbuf = NULL;
 487                 ops.mode = MTD_OOB_PLACE;
 488
 489                 if (ops.ooboffs && ops.len > (ops.ooblen - ops.ooboffs))
 490                         return -EINVAL;
 491
 492                 ops.oobbuf = kmalloc(buf.length, GFP_KERNEL);
 493                 if (!ops.oobbuf)
 494                         return -ENOMEM;
 495
 496                 buf.start &= ~(mtd->oobsize - 1);
 497                 ret = mtd->read_oob(mtd, buf.start, &ops);
 498
 499                 if (put_user(ops.retlen, (uint32_t __user *)argp))
 500                         ret = -EFAULT;
 501                 else if (ops.retlen && copy_to_user(buf.ptr, ops.oobbuf,
 502                                                     ops.retlen))
 503                         ret = -EFAULT;
 504
 505                 kfree(ops.oobbuf);
 506                 break;
 507         }
 508
 509         case MEMLOCK:
 510         {
 511                 struct erase_info_user info;
 512
 513                 if (copy_from_user(&info, argp, sizeof(info)))
 514                         return -EFAULT;
 515
 516                 if (!mtd->lock)
 517                         ret = -EOPNOTSUPP;
 518                 else
 519                         ret = mtd->lock(mtd, info.start, info.length);
 520                 break;
 521         }
 522
 523         case MEMUNLOCK:
 524         {
 525                 struct erase_info_user info;
 526
 527                 if (copy_from_user(&info, argp, sizeof(info)))
 528                         return -EFAULT;
 529
 530                 if (!mtd->unlock)
 531                         ret = -EOPNOTSUPP;
 532                 else
 533                         ret = mtd->unlock(mtd, info.start, info.length);
 534                 break;
 535         }
 536
 537         /* Legacy interface */
 538         case MEMGETOOBSEL:
 539         {
 540                 struct nand_oobinfo oi;
 541
 542                 if (!mtd->ecclayout)
 543                         return -EOPNOTSUPP;
 544                 if (mtd->ecclayout->eccbytes > ARRAY_SIZE(oi.eccpos))
 545                         return -EINVAL;
 546
 547                 oi.useecc = MTD_NANDECC_AUTOPLACE;
 548                 memcpy(&oi.eccpos, mtd->ecclayout->eccpos, sizeof(oi.eccpos));
 549                 memcpy(&oi.oobfree, mtd->ecclayout->oobfree,
 550                        sizeof(oi.oobfree));
 551
 552                 if (copy_to_user(argp, &oi, sizeof(struct nand_oobinfo)))
 553                         return -EFAULT;
 554                 break;
 555         }
 556
 557         case ECCGETLAYOUT:
 558
 559                 if (!mtd->ecclayout)
 560                         return -EOPNOTSUPP;
 561
 562                 if (copy_to_user(argp, &mtd->ecclayout,
 563                                  sizeof(struct nand_ecclayout)))
 564                         return -EFAULT;
 565                 break;
 566
 567         case MEMGETBADBLOCK:
 568         {
 569                 loff_t offs;
 570
 571                 if (copy_from_user(&offs, argp, sizeof(loff_t)))
 572                         return -EFAULT;
 573                 if (!mtd->block_isbad)
 574                         ret = -EOPNOTSUPP;
 575                 else
 576                         return mtd->block_isbad(mtd, offs);
 577                 break;
 578         }
 579
 580         case MEMSETBADBLOCK:
 581         {
 582                 loff_t offs;
 583
 584                 if (copy_from_user(&offs, argp, sizeof(loff_t)))
 585                         return -EFAULT;
 586                 if (!mtd->block_markbad)
 587                         ret = -EOPNOTSUPP;
 588                 else
 589                         return mtd->block_markbad(mtd, offs);
 590                 break;
 591         }
 592
 593 #if defined(CONFIG_MTD_OTP) || defined(CONFIG_MTD_ONENAND_OTP)
 594         case OTPSELECT:
 595         {
 596                 int mode;
 597                 if (copy_from_user(&mode, argp, sizeof(int)))
 598                         return -EFAULT;
 599                 SET_MTD_MODE(file, 0);
 600                 switch (mode) {
 601                 case MTD_OTP_FACTORY:
 602                         if (!mtd->read_fact_prot_reg)
 603                                 ret = -EOPNOTSUPP;
 604                         else
 605                                 SET_MTD_MODE(file, MTD_MODE_OTP_FACT);
 606                         break;
 607                 case MTD_OTP_USER:
 608                         if (!mtd->read_fact_prot_reg)
 609                                 ret = -EOPNOTSUPP;
 610                         else
 611                                 SET_MTD_MODE(file, MTD_MODE_OTP_USER);
 612                         break;
 613                 default:
 614                         ret = -EINVAL;
 615                 case MTD_OTP_OFF:
 616                         break;
 617                 }
 618                 file->f_pos = 0;
 619                 break;
 620         }
 621
 622         case OTPGETREGIONCOUNT:
 623         case OTPGETREGIONINFO:
 624         {
 625                 struct otp_info *buf = kmalloc(4096, GFP_KERNEL);
 626                 if (!buf)
 627                         return -ENOMEM;
 628                 ret = -EOPNOTSUPP;
 629                 switch (MTD_MODE(file)) {
 630                 case MTD_MODE_OTP_FACT:
 631                         if (mtd->get_fact_prot_info)
 632                                 ret = mtd->get_fact_prot_info(mtd, buf, 4096);
 633                         break;
 634                 case MTD_MODE_OTP_USER:
 635                         if (mtd->get_user_prot_info)
 636                                 ret = mtd->get_user_prot_info(mtd, buf, 4096);
 637                         break;
 638                 }
 639                 if (ret >= 0) {
 640                         if (cmd == OTPGETREGIONCOUNT) {
 641                                 int nbr = ret / sizeof(struct otp_info);
 642                                 ret = copy_to_user(argp, &nbr, sizeof(int));
 643                         } else
 644                                 ret = copy_to_user(argp, buf, ret);
 645                         if (ret)
 646                                 ret = -EFAULT;
 647                 }
 648                 kfree(buf);
 649                 break;
 650         }
 651
 652         case OTPLOCK:
 653         {
 654                 struct otp_info info;
 655
 656                 if (MTD_MODE(file) != MTD_MODE_OTP_USER)
 657                         return -EINVAL;
 658                 if (copy_from_user(&info, argp, sizeof(info)))
 659                         return -EFAULT;
 660                 if (!mtd->lock_user_prot_reg)
 661                         return -EOPNOTSUPP;
 662                 ret = mtd->lock_user_prot_reg(mtd, info.start, info.length);
 663                 break;
 664         }
 665 #endif
 666
 667         default:
 668                 ret = -ENOTTY;
 669         }
 670
 671         return ret;
 672 } /* memory_ioctl */
 673
 674 static struct file_operations mtd_fops = {
 675         .owner          = THIS_MODULE,
 676         .llseek         = mtd_lseek,
 677         .read           = mtd_read,
 678         .write          = mtd_write,
 679         .ioctl          = mtd_ioctl,
 680         .open           = mtd_open,
 681         .release        = mtd_close,
 682 };
 683
 684 static int __init init_mtdchar(void)
 685 {
 686         if (register_chrdev(MTD_CHAR_MAJOR, "mtd", &mtd_fops)) {
 687                 printk(KERN_NOTICE "Can't allocate major number %d for Memory Technology Devices.\n",
 688                        MTD_CHAR_MAJOR);
 689                 return -EAGAIN;
 690         }
 691
 692         mtd_class = class_create(THIS_MODULE, "mtd");
 693
 694         if (IS_ERR(mtd_class)) {
 695                 printk(KERN_ERR "Error creating mtd class.\n");
 696                 unregister_chrdev(MTD_CHAR_MAJOR, "mtd");
 697                 return PTR_ERR(mtd_class);
 698         }
 699
 700         register_mtd_user(&notifier);
 701         return 0;
 702 }
 703
 704 static void __exit cleanup_mtdchar(void)
 705 {
 706         unregister_mtd_user(&notifier);
 707         class_destroy(mtd_class);
 708         unregister_chrdev(MTD_CHAR_MAJOR, "mtd");
 709 }
 710
 711 module_init(init_mtdchar);
 712 module_exit(cleanup_mtdchar);
 713
 714
 715 MODULE_LICENSE("GPL");
 716 MODULE_AUTHOR("David Woodhouse <dwmw2@infradead.org>");
 717 MODULE_DESCRIPTION("Direct character-device access to MTD devices");