drivers/mtd/mtdchar.c

   1 /*
   2  * Character-device access to raw MTD devices.
   3  *
   4  */
   5
   6 #include <linux/device.h>
   7 #include <linux/fs.h>
   8 #include <linux/mm.h>
   9 #include <linux/err.h>
  10 #include <linux/init.h>
  11 #include <linux/kernel.h>
  12 #include <linux/module.h>
  13 #include <linux/slab.h>
  14 #include <linux/sched.h>
  15 #include <linux/smp_lock.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         device_create(mtd_class, NULL, MKDEV(MTD_CHAR_MAJOR, mtd->index*2),
  30                       NULL, "mtd%d", mtd->index);
  31
  32         device_create(mtd_class, NULL, MKDEV(MTD_CHAR_MAJOR, mtd->index*2+1),
  33                       NULL, "mtd%dro", mtd->index);
  34 }
  35
  36 static void mtd_notify_remove(struct mtd_info* mtd)
  37 {
  38         if (!mtd)
  39                 return;
  40
  41         device_destroy(mtd_class, MKDEV(MTD_CHAR_MAJOR, mtd->index*2));
  42         device_destroy(mtd_class, MKDEV(MTD_CHAR_MAJOR, mtd->index*2+1));
  43 }
  44
  45 static struct mtd_notifier notifier = {
  46         .add    = mtd_notify_add,
  47         .remove = mtd_notify_remove,
  48 };
  49
  50 /*
  51  * Data structure to hold the pointer to the mtd device as well
  52  * as mode information ofr various use cases.
  53  */
  54 struct mtd_file_info {
  55         struct mtd_info *mtd;
  56         enum mtd_file_modes mode;
  57 };
  58
  59 static loff_t mtd_lseek (struct file *file, loff_t offset, int orig)
  60 {
  61         struct mtd_file_info *mfi = file->private_data;
  62         struct mtd_info *mtd = mfi->mtd;
  63
  64         switch (orig) {
  65         case SEEK_SET:
  66                 break;
  67         case SEEK_CUR:
  68                 offset += file->f_pos;
  69                 break;
  70         case SEEK_END:
  71                 offset += mtd->size;
  72                 break;
  73         default:
  74                 return -EINVAL;
  75         }
  76
  77         if (offset >= 0 && offset <= mtd->size)
  78                 return file->f_pos = offset;
  79
  80         return -EINVAL;
  81 }
  82
  83
  84
  85 static int mtd_open(struct inode *inode, struct file *file)
  86 {
  87         int minor = iminor(inode);
  88         int devnum = minor >> 1;
  89         int ret = 0;
  90         struct mtd_info *mtd;
  91         struct mtd_file_info *mfi;
  92
  93         DEBUG(MTD_DEBUG_LEVEL0, "MTD_open\n");
  94
  95         if (devnum >= MAX_MTD_DEVICES)
  96                 return -ENODEV;
  97
  98         /* You can't open the RO devices RW */
  99         if ((file->f_mode & FMODE_WRITE) && (minor & 1))
 100                 return -EACCES;
 101
 102         lock_kernel();
 103         mtd = get_mtd_device(NULL, devnum);
 104
 105         if (IS_ERR(mtd)) {
 106                 ret = PTR_ERR(mtd);
 107                 goto out;
 108         }
 109
 110         if (MTD_ABSENT == mtd->type) {
 111                 put_mtd_device(mtd);
 112                 ret = -ENODEV;
 113                 goto out;
 114         }
 115
 116         /* You can't open it RW if it's not a writeable device */
 117         if ((file->f_mode & FMODE_WRITE) && !(mtd->flags & MTD_WRITEABLE)) {
 118                 put_mtd_device(mtd);
 119                 ret = -EACCES;
 120                 goto out;
 121         }
 122
 123         mfi = kzalloc(sizeof(*mfi), GFP_KERNEL);
 124         if (!mfi) {
 125                 put_mtd_device(mtd);
 126                 ret = -ENOMEM;
 127                 goto out;
 128         }
 129         mfi->mtd = mtd;
 130         file->private_data = mfi;
 131
 132 out:
 133         unlock_kernel();
 134         return ret;
 135 } /* mtd_open */
 136
 137 /*====================================================================*/
 138
 139 static int mtd_close(struct inode *inode, struct file *file)
 140 {
 141         struct mtd_file_info *mfi = file->private_data;
 142         struct mtd_info *mtd = mfi->mtd;
 143
 144         DEBUG(MTD_DEBUG_LEVEL0, "MTD_close\n");
 145
 146         /* Only sync if opened RW */
 147         if ((file->f_mode & FMODE_WRITE) && mtd->sync)
 148                 mtd->sync(mtd);
 149
 150         put_mtd_device(mtd);
 151         file->private_data = NULL;
 152         kfree(mfi);
 153
 154         return 0;
 155 } /* mtd_close */
 156
 157 /* FIXME: This _really_ needs to die. In 2.5, we should lock the
 158    userspace buffer down and use it directly with readv/writev.
 159 */
 160 #define MAX_KMALLOC_SIZE 0x20000
 161
 162 static ssize_t mtd_read(struct file *file, char __user *buf, size_t count,loff_t *ppos)
 163 {
 164         struct mtd_file_info *mfi = file->private_data;
 165         struct mtd_info *mtd = mfi->mtd;
 166         size_t retlen=0;
 167         size_t total_retlen=0;
 168         int ret=0;
 169         int len;
 170         char *kbuf;
 171
 172         DEBUG(MTD_DEBUG_LEVEL0,"MTD_read\n");
 173
 174         if (*ppos + count > mtd->size)
 175                 count = mtd->size - *ppos;
 176
 177         if (!count)
 178                 return 0;
 179
 180         /* FIXME: Use kiovec in 2.5 to lock down the user's buffers
 181            and pass them directly to the MTD functions */
 182
 183         if (count > MAX_KMALLOC_SIZE)
 184                 kbuf=kmalloc(MAX_KMALLOC_SIZE, GFP_KERNEL);
 185         else
 186                 kbuf=kmalloc(count, GFP_KERNEL);
 187
 188         if (!kbuf)
 189                 return -ENOMEM;
 190
 191         while (count) {
 192
 193                 if (count > MAX_KMALLOC_SIZE)
 194                         len = MAX_KMALLOC_SIZE;
 195                 else
 196                         len = count;
 197
 198                 switch (mfi->mode) {
 199                 case MTD_MODE_OTP_FACTORY:
 200                         ret = mtd->read_fact_prot_reg(mtd, *ppos, len, &retlen, kbuf);
 201                         break;
 202                 case MTD_MODE_OTP_USER:
 203                         ret = mtd->read_user_prot_reg(mtd, *ppos, len, &retlen, kbuf);
 204                         break;
 205                 case MTD_MODE_RAW:
 206                 {
 207                         struct mtd_oob_ops ops;
 208
 209                         ops.mode = MTD_OOB_RAW;
 210                         ops.datbuf = kbuf;
 211                         ops.oobbuf = NULL;
 212                         ops.len = len;
 213
 214                         ret = mtd->read_oob(mtd, *ppos, &ops);
 215                         retlen = ops.retlen;
 216                         break;
 217                 }
 218                 default:
 219                         ret = mtd->read(mtd, *ppos, len, &retlen, kbuf);
 220                 }
 221                 /* Nand returns -EBADMSG on ecc errors, but it returns
 222                  * the data. For our userspace tools it is important
 223                  * to dump areas with ecc errors !
 224                  * For kernel internal usage it also might return -EUCLEAN
 225                  * to signal the caller that a bitflip has occured and has
 226                  * been corrected by the ECC algorithm.
 227                  * Userspace software which accesses NAND this way
 228                  * must be aware of the fact that it deals with NAND
 229                  */
 230                 if (!ret || (ret == -EUCLEAN) || (ret == -EBADMSG)) {
 231                         *ppos += retlen;
 232                         if (copy_to_user(buf, kbuf, retlen)) {
 233                                 kfree(kbuf);
 234                                 return -EFAULT;
 235                         }
 236                         else
 237                                 total_retlen += retlen;
 238
 239                         count -= retlen;
 240                         buf += retlen;
 241                         if (retlen == 0)
 242                                 count = 0;
 243                 }
 244                 else {
 245                         kfree(kbuf);
 246                         return ret;
 247                 }
 248
 249         }
 250
 251         kfree(kbuf);
 252         return total_retlen;
 253 } /* mtd_read */
 254
 255 static ssize_t mtd_write(struct file *file, const char __user *buf, size_t count,loff_t *ppos)
 256 {
 257         struct mtd_file_info *mfi = file->private_data;
 258         struct mtd_info *mtd = mfi->mtd;
 259         char *kbuf;
 260         size_t retlen;
 261         size_t total_retlen=0;
 262         int ret=0;
 263         int len;
 264
 265         DEBUG(MTD_DEBUG_LEVEL0,"MTD_write\n");
 266
 267         if (*ppos == mtd->size)
 268                 return -ENOSPC;
 269
 270         if (*ppos + count > mtd->size)
 271                 count = mtd->size - *ppos;
 272
 273         if (!count)
 274                 return 0;
 275
 276         if (count > MAX_KMALLOC_SIZE)
 277                 kbuf=kmalloc(MAX_KMALLOC_SIZE, GFP_KERNEL);
 278         else
 279                 kbuf=kmalloc(count, GFP_KERNEL);
 280
 281         if (!kbuf)
 282                 return -ENOMEM;
 283
 284         while (count) {
 285
 286                 if (count > MAX_KMALLOC_SIZE)
 287                         len = MAX_KMALLOC_SIZE;
 288                 else
 289                         len = count;
 290
 291                 if (copy_from_user(kbuf, buf, len)) {
 292                         kfree(kbuf);
 293                         return -EFAULT;
 294                 }
 295
 296                 switch (mfi->mode) {
 297                 case MTD_MODE_OTP_FACTORY:
 298                         ret = -EROFS;
 299                         break;
 300                 case MTD_MODE_OTP_USER:
 301                         if (!mtd->write_user_prot_reg) {
 302                                 ret = -EOPNOTSUPP;
 303                                 break;
 304                         }
 305                         ret = mtd->write_user_prot_reg(mtd, *ppos, len, &retlen, kbuf);
 306                         break;
 307
 308                 case MTD_MODE_RAW:
 309                 {
 310                         struct mtd_oob_ops ops;
 311
 312                         ops.mode = MTD_OOB_RAW;
 313                         ops.datbuf = kbuf;
 314                         ops.oobbuf = NULL;
 315                         ops.len = len;
 316
 317                         ret = mtd->write_oob(mtd, *ppos, &ops);
 318                         retlen = ops.retlen;
 319                         break;
 320                 }
 321
 322                 default:
 323                         ret = (*(mtd->write))(mtd, *ppos, len, &retlen, kbuf);
 324                 }
 325                 if (!ret) {
 326                         *ppos += retlen;
 327                         total_retlen += retlen;
 328                         count -= retlen;
 329                         buf += retlen;
 330                 }
 331                 else {
 332                         kfree(kbuf);
 333                         return ret;
 334                 }
 335         }
 336
 337         kfree(kbuf);
 338         return total_retlen;
 339 } /* mtd_write */
 340
 341 /*======================================================================
 342
 343     IOCTL calls for getting device parameters.
 344
 345 ======================================================================*/
 346 static void mtdchar_erase_callback (struct erase_info *instr)
 347 {
 348         wake_up((wait_queue_head_t *)instr->priv);
 349 }
 350
 351 #ifdef CONFIG_HAVE_MTD_OTP
 352 static int otp_select_filemode(struct mtd_file_info *mfi, int mode)
 353 {
 354         struct mtd_info *mtd = mfi->mtd;
 355         int ret = 0;
 356
 357         switch (mode) {
 358         case MTD_OTP_FACTORY:
 359                 if (!mtd->read_fact_prot_reg)
 360                         ret = -EOPNOTSUPP;
 361                 else
 362                         mfi->mode = MTD_MODE_OTP_FACTORY;
 363                 break;
 364         case MTD_OTP_USER:
 365                 if (!mtd->read_fact_prot_reg)
 366                         ret = -EOPNOTSUPP;
 367                 else
 368                         mfi->mode = MTD_MODE_OTP_USER;
 369                 break;
 370         default:
 371                 ret = -EINVAL;
 372         case MTD_OTP_OFF:
 373                 break;
 374         }
 375         return ret;
 376 }
 377 #else
 378 # define otp_select_filemode(f,m)       -EOPNOTSUPP
 379 #endif
 380
 381 static int mtd_ioctl(struct inode *inode, struct file *file,
 382                      u_int cmd, u_long arg)
 383 {
 384         struct mtd_file_info *mfi = file->private_data;
 385         struct mtd_info *mtd = mfi->mtd;
 386         void __user *argp = (void __user *)arg;
 387         int ret = 0;
 388         u_long size;
 389         struct mtd_info_user info;
 390
 391         DEBUG(MTD_DEBUG_LEVEL0, "MTD_ioctl\n");
 392
 393         size = (cmd & IOCSIZE_MASK) >> IOCSIZE_SHIFT;
 394         if (cmd & IOC_IN) {
 395                 if (!access_ok(VERIFY_READ, argp, size))
 396                         return -EFAULT;
 397         }
 398         if (cmd & IOC_OUT) {
 399                 if (!access_ok(VERIFY_WRITE, argp, size))
 400                         return -EFAULT;
 401         }
 402
 403         switch (cmd) {
 404         case MEMGETREGIONCOUNT:
 405                 if (copy_to_user(argp, &(mtd->numeraseregions), sizeof(int)))
 406                         return -EFAULT;
 407                 break;
 408
 409         case MEMGETREGIONINFO:
 410         {
 411                 uint32_t ur_idx;
 412                 struct mtd_erase_region_info *kr;
 413                 struct region_info_user *ur = (struct region_info_user *) argp;
 414
 415                 if (get_user(ur_idx, &(ur->regionindex)))
 416                         return -EFAULT;
 417
 418                 kr = &(mtd->eraseregions[ur_idx]);
 419
 420                 if (put_user(kr->offset, &(ur->offset))
 421                     || put_user(kr->erasesize, &(ur->erasesize))
 422                     || put_user(kr->numblocks, &(ur->numblocks)))
 423                         return -EFAULT;
 424
 425                 break;
 426         }
 427
 428         case MEMGETINFO:
 429                 info.type       = mtd->type;
 430                 info.flags      = mtd->flags;
 431                 info.size       = mtd->size;
 432                 info.erasesize  = mtd->erasesize;
 433                 info.writesize  = mtd->writesize;
 434                 info.oobsize    = mtd->oobsize;
 435                 /* The below fields are obsolete */
 436                 info.ecctype    = -1;
 437                 info.eccsize    = 0;
 438                 if (copy_to_user(argp, &info, sizeof(struct mtd_info_user)))
 439                         return -EFAULT;
 440                 break;
 441
 442         case MEMERASE:
 443         {
 444                 struct erase_info *erase;
 445
 446                 if(!(file->f_mode & FMODE_WRITE))
 447                         return -EPERM;
 448
 449                 erase=kzalloc(sizeof(struct erase_info),GFP_KERNEL);
 450                 if (!erase)
 451                         ret = -ENOMEM;
 452                 else {
 453                         struct erase_info_user einfo;
 454
 455                         wait_queue_head_t waitq;
 456                         DECLARE_WAITQUEUE(wait, current);
 457
 458                         init_waitqueue_head(&waitq);
 459
 460                         if (copy_from_user(&einfo, argp,
 461                                     sizeof(struct erase_info_user))) {
 462                                 kfree(erase);
 463                                 return -EFAULT;
 464                         }
 465                         erase->addr = einfo.start;
 466                         erase->len = einfo.length;
 467                         erase->mtd = mtd;
 468                         erase->callback = mtdchar_erase_callback;
 469                         erase->priv = (unsigned long)&waitq;
 470
 471                         /*
 472                           FIXME: Allow INTERRUPTIBLE. Which means
 473                           not having the wait_queue head on the stack.
 474
 475                           If the wq_head is on the stack, and we
 476                           leave because we got interrupted, then the
 477                           wq_head is no longer there when the
 478                           callback routine tries to wake us up.
 479                         */
 480                         ret = mtd->erase(mtd, erase);
 481                         if (!ret) {
 482                                 set_current_state(TASK_UNINTERRUPTIBLE);
 483                                 add_wait_queue(&waitq, &wait);
 484                                 if (erase->state != MTD_ERASE_DONE &&
 485                                     erase->state != MTD_ERASE_FAILED)
 486                                         schedule();
 487                                 remove_wait_queue(&waitq, &wait);
 488                                 set_current_state(TASK_RUNNING);
 489
 490                                 ret = (erase->state == MTD_ERASE_FAILED)?-EIO:0;
 491                         }
 492                         kfree(erase);
 493                 }
 494                 break;
 495         }
 496
 497         case MEMWRITEOOB:
 498         {
 499                 struct mtd_oob_buf buf;
 500                 struct mtd_oob_ops ops;
 501                 struct mtd_oob_buf __user *user_buf = argp;
 502                 uint32_t retlen;
 503
 504                 if(!(file->f_mode & FMODE_WRITE))
 505                         return -EPERM;
 506
 507                 if (copy_from_user(&buf, argp, sizeof(struct mtd_oob_buf)))
 508                         return -EFAULT;
 509
 510                 if (buf.length > 4096)
 511                         return -EINVAL;
 512
 513                 if (!mtd->write_oob)
 514                         ret = -EOPNOTSUPP;
 515                 else
 516                         ret = access_ok(VERIFY_READ, buf.ptr,
 517                                         buf.length) ? 0 : EFAULT;
 518
 519                 if (ret)
 520                         return ret;
 521
 522                 ops.ooblen = buf.length;
 523                 ops.ooboffs = buf.start & (mtd->oobsize - 1);
 524                 ops.datbuf = NULL;
 525                 ops.mode = MTD_OOB_PLACE;
 526
 527                 if (ops.ooboffs && ops.ooblen > (mtd->oobsize - ops.ooboffs))
 528                         return -EINVAL;
 529
 530                 ops.oobbuf = kmalloc(buf.length, GFP_KERNEL);
 531                 if (!ops.oobbuf)
 532                         return -ENOMEM;
 533
 534                 if (copy_from_user(ops.oobbuf, buf.ptr, buf.length)) {
 535                         kfree(ops.oobbuf);
 536                         return -EFAULT;
 537                 }
 538
 539                 buf.start &= ~(mtd->oobsize - 1);
 540                 ret = mtd->write_oob(mtd, buf.start, &ops);
 541
 542                 if (ops.oobretlen > 0xFFFFFFFFU)
 543                         ret = -EOVERFLOW;
 544                 retlen = ops.oobretlen;
 545                 if (copy_to_user(&user_buf->length, &retlen, sizeof(buf.length)))
 546                         ret = -EFAULT;
 547
 548                 kfree(ops.oobbuf);
 549                 break;
 550
 551         }
 552
 553         case MEMREADOOB:
 554         {
 555                 struct mtd_oob_buf buf;
 556                 struct mtd_oob_ops ops;
 557
 558                 if (copy_from_user(&buf, argp, sizeof(struct mtd_oob_buf)))
 559                         return -EFAULT;
 560
 561                 if (buf.length > 4096)
 562                         return -EINVAL;
 563
 564                 if (!mtd->read_oob)
 565                         ret = -EOPNOTSUPP;
 566                 else
 567                         ret = access_ok(VERIFY_WRITE, buf.ptr,
 568                                         buf.length) ? 0 : -EFAULT;
 569                 if (ret)
 570                         return ret;
 571
 572                 ops.ooblen = buf.length;
 573                 ops.ooboffs = buf.start & (mtd->oobsize - 1);
 574                 ops.datbuf = NULL;
 575                 ops.mode = MTD_OOB_PLACE;
 576
 577                 if (ops.ooboffs && ops.ooblen > (mtd->oobsize - ops.ooboffs))
 578                         return -EINVAL;
 579
 580                 ops.oobbuf = kmalloc(buf.length, GFP_KERNEL);
 581                 if (!ops.oobbuf)
 582                         return -ENOMEM;
 583
 584                 buf.start &= ~(mtd->oobsize - 1);
 585                 ret = mtd->read_oob(mtd, buf.start, &ops);
 586
 587                 if (put_user(ops.oobretlen, (uint32_t __user *)argp))
 588                         ret = -EFAULT;
 589                 else if (ops.oobretlen && copy_to_user(buf.ptr, ops.oobbuf,
 590                                                     ops.oobretlen))
 591                         ret = -EFAULT;
 592
 593                 kfree(ops.oobbuf);
 594                 break;
 595         }
 596
 597         case MEMLOCK:
 598         {
 599                 struct erase_info_user einfo;
 600
 601                 if (copy_from_user(&einfo, argp, sizeof(einfo)))
 602                         return -EFAULT;
 603
 604                 if (!mtd->lock)
 605                         ret = -EOPNOTSUPP;
 606                 else
 607                         ret = mtd->lock(mtd, einfo.start, einfo.length);
 608                 break;
 609         }
 610
 611         case MEMUNLOCK:
 612         {
 613                 struct erase_info_user einfo;
 614
 615                 if (copy_from_user(&einfo, argp, sizeof(einfo)))
 616                         return -EFAULT;
 617
 618                 if (!mtd->unlock)
 619                         ret = -EOPNOTSUPP;
 620                 else
 621                         ret = mtd->unlock(mtd, einfo.start, einfo.length);
 622                 break;
 623         }
 624
 625         /* Legacy interface */
 626         case MEMGETOOBSEL:
 627         {
 628                 struct nand_oobinfo oi;
 629
 630                 if (!mtd->ecclayout)
 631                         return -EOPNOTSUPP;
 632                 if (mtd->ecclayout->eccbytes > ARRAY_SIZE(oi.eccpos))
 633                         return -EINVAL;
 634
 635                 oi.useecc = MTD_NANDECC_AUTOPLACE;
 636                 memcpy(&oi.eccpos, mtd->ecclayout->eccpos, sizeof(oi.eccpos));
 637                 memcpy(&oi.oobfree, mtd->ecclayout->oobfree,
 638                        sizeof(oi.oobfree));
 639                 oi.eccbytes = mtd->ecclayout->eccbytes;
 640
 641                 if (copy_to_user(argp, &oi, sizeof(struct nand_oobinfo)))
 642                         return -EFAULT;
 643                 break;
 644         }
 645
 646         case MEMGETBADBLOCK:
 647         {
 648                 loff_t offs;
 649
 650                 if (copy_from_user(&offs, argp, sizeof(loff_t)))
 651                         return -EFAULT;
 652                 if (!mtd->block_isbad)
 653                         ret = -EOPNOTSUPP;
 654                 else
 655                         return mtd->block_isbad(mtd, offs);
 656                 break;
 657         }
 658
 659         case MEMSETBADBLOCK:
 660         {
 661                 loff_t offs;
 662
 663                 if (copy_from_user(&offs, argp, sizeof(loff_t)))
 664                         return -EFAULT;
 665                 if (!mtd->block_markbad)
 666                         ret = -EOPNOTSUPP;
 667                 else
 668                         return mtd->block_markbad(mtd, offs);
 669                 break;
 670         }
 671
 672 #ifdef CONFIG_HAVE_MTD_OTP
 673         case OTPSELECT:
 674         {
 675                 int mode;
 676                 if (copy_from_user(&mode, argp, sizeof(int)))
 677                         return -EFAULT;
 678
 679                 mfi->mode = MTD_MODE_NORMAL;
 680
 681                 ret = otp_select_filemode(mfi, mode);
 682
 683                 file->f_pos = 0;
 684                 break;
 685         }
 686
 687         case OTPGETREGIONCOUNT:
 688         case OTPGETREGIONINFO:
 689         {
 690                 struct otp_info *buf = kmalloc(4096, GFP_KERNEL);
 691                 if (!buf)
 692                         return -ENOMEM;
 693                 ret = -EOPNOTSUPP;
 694                 switch (mfi->mode) {
 695                 case MTD_MODE_OTP_FACTORY:
 696                         if (mtd->get_fact_prot_info)
 697                                 ret = mtd->get_fact_prot_info(mtd, buf, 4096);
 698                         break;
 699                 case MTD_MODE_OTP_USER:
 700                         if (mtd->get_user_prot_info)
 701                                 ret = mtd->get_user_prot_info(mtd, buf, 4096);
 702                         break;
 703                 default:
 704                         break;
 705                 }
 706                 if (ret >= 0) {
 707                         if (cmd == OTPGETREGIONCOUNT) {
 708                                 int nbr = ret / sizeof(struct otp_info);
 709                                 ret = copy_to_user(argp, &nbr, sizeof(int));
 710                         } else
 711                                 ret = copy_to_user(argp, buf, ret);
 712                         if (ret)
 713                                 ret = -EFAULT;
 714                 }
 715                 kfree(buf);
 716                 break;
 717         }
 718
 719         case OTPLOCK:
 720         {
 721                 struct otp_info oinfo;
 722
 723                 if (mfi->mode != MTD_MODE_OTP_USER)
 724                         return -EINVAL;
 725                 if (copy_from_user(&oinfo, argp, sizeof(oinfo)))
 726                         return -EFAULT;
 727                 if (!mtd->lock_user_prot_reg)
 728                         return -EOPNOTSUPP;
 729                 ret = mtd->lock_user_prot_reg(mtd, oinfo.start, oinfo.length);
 730                 break;
 731         }
 732 #endif
 733
 734         case ECCGETLAYOUT:
 735         {
 736                 if (!mtd->ecclayout)
 737                         return -EOPNOTSUPP;
 738
 739                 if (copy_to_user(argp, mtd->ecclayout,
 740                                  sizeof(struct nand_ecclayout)))
 741                         return -EFAULT;
 742                 break;
 743         }
 744
 745         case ECCGETSTATS:
 746         {
 747                 if (copy_to_user(argp, &mtd->ecc_stats,
 748                                  sizeof(struct mtd_ecc_stats)))
 749                         return -EFAULT;
 750                 break;
 751         }
 752
 753         case MTDFILEMODE:
 754         {
 755                 mfi->mode = 0;
 756
 757                 switch(arg) {
 758                 case MTD_MODE_OTP_FACTORY:
 759                 case MTD_MODE_OTP_USER:
 760                         ret = otp_select_filemode(mfi, arg);
 761                         break;
 762
 763                 case MTD_MODE_RAW:
 764                         if (!mtd->read_oob || !mtd->write_oob)
 765                                 return -EOPNOTSUPP;
 766                         mfi->mode = arg;
 767
 768                 case MTD_MODE_NORMAL:
 769                         break;
 770                 default:
 771                         ret = -EINVAL;
 772                 }
 773                 file->f_pos = 0;
 774                 break;
 775         }
 776
 777         default:
 778                 ret = -ENOTTY;
 779         }
 780
 781         return ret;
 782 } /* memory_ioctl */
 783
 784 static const struct file_operations mtd_fops = {
 785         .owner          = THIS_MODULE,
 786         .llseek         = mtd_lseek,
 787         .read           = mtd_read,
 788         .write          = mtd_write,
 789         .ioctl          = mtd_ioctl,
 790         .open           = mtd_open,
 791         .release        = mtd_close,
 792 };
 793
 794 static int __init init_mtdchar(void)
 795 {
 796         if (register_chrdev(MTD_CHAR_MAJOR, "mtd", &mtd_fops)) {
 797                 printk(KERN_NOTICE "Can't allocate major number %d for Memory Technology Devices.\n",
 798                        MTD_CHAR_MAJOR);
 799                 return -EAGAIN;
 800         }
 801
 802         mtd_class = class_create(THIS_MODULE, "mtd");
 803
 804         if (IS_ERR(mtd_class)) {
 805                 printk(KERN_ERR "Error creating mtd class.\n");
 806                 unregister_chrdev(MTD_CHAR_MAJOR, "mtd");
 807                 return PTR_ERR(mtd_class);
 808         }
 809
 810         register_mtd_user(&notifier);
 811         return 0;
 812 }
 813
 814 static void __exit cleanup_mtdchar(void)
 815 {
 816         unregister_mtd_user(&notifier);
 817         class_destroy(mtd_class);
 818         unregister_chrdev(MTD_CHAR_MAJOR, "mtd");
 819 }
 820
 821 module_init(init_mtdchar);
 822 module_exit(cleanup_mtdchar);
 823
 824
 825 MODULE_LICENSE("GPL");
 826 MODULE_AUTHOR("David Woodhouse <dwmw2@infradead.org>");
 827 MODULE_DESCRIPTION("Direct character-device access to MTD devices");