[LMC]: lmc_main wants to use skb_tailroom
[linux-2.6] / drivers / mtd / mtdchar.c
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/device.h>
9 #include <linux/fs.h>
10 #include <linux/err.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  * Data structure to hold the pointer to the mtd device as well
53  * as mode information ofr various use cases.
54  */
55 struct mtd_file_info {
56         struct mtd_info *mtd;
57         enum mtd_file_modes mode;
58 };
59
60 static loff_t mtd_lseek (struct file *file, loff_t offset, int orig)
61 {
62         struct mtd_file_info *mfi = file->private_data;
63         struct mtd_info *mtd = mfi->mtd;
64
65         switch (orig) {
66         case SEEK_SET:
67                 break;
68         case SEEK_CUR:
69                 offset += file->f_pos;
70                 break;
71         case SEEK_END:
72                 offset += mtd->size;
73                 break;
74         default:
75                 return -EINVAL;
76         }
77
78         if (offset >= 0 && offset <= mtd->size)
79                 return file->f_pos = offset;
80
81         return -EINVAL;
82 }
83
84
85
86 static int mtd_open(struct inode *inode, struct file *file)
87 {
88         int minor = iminor(inode);
89         int devnum = minor >> 1;
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 & 2) && (minor & 1))
100                 return -EACCES;
101
102         mtd = get_mtd_device(NULL, devnum);
103
104         if (IS_ERR(mtd))
105                 return PTR_ERR(mtd);
106
107         if (MTD_ABSENT == mtd->type) {
108                 put_mtd_device(mtd);
109                 return -ENODEV;
110         }
111
112         /* You can't open it RW if it's not a writeable device */
113         if ((file->f_mode & 2) && !(mtd->flags & MTD_WRITEABLE)) {
114                 put_mtd_device(mtd);
115                 return -EACCES;
116         }
117
118         mfi = kzalloc(sizeof(*mfi), GFP_KERNEL);
119         if (!mfi) {
120                 put_mtd_device(mtd);
121                 return -ENOMEM;
122         }
123         mfi->mtd = mtd;
124         file->private_data = mfi;
125
126         return 0;
127 } /* mtd_open */
128
129 /*====================================================================*/
130
131 static int mtd_close(struct inode *inode, struct file *file)
132 {
133         struct mtd_file_info *mfi = file->private_data;
134         struct mtd_info *mtd = mfi->mtd;
135
136         DEBUG(MTD_DEBUG_LEVEL0, "MTD_close\n");
137
138         if (mtd->sync)
139                 mtd->sync(mtd);
140
141         put_mtd_device(mtd);
142         file->private_data = NULL;
143         kfree(mfi);
144
145         return 0;
146 } /* mtd_close */
147
148 /* FIXME: This _really_ needs to die. In 2.5, we should lock the
149    userspace buffer down and use it directly with readv/writev.
150 */
151 #define MAX_KMALLOC_SIZE 0x20000
152
153 static ssize_t mtd_read(struct file *file, char __user *buf, size_t count,loff_t *ppos)
154 {
155         struct mtd_file_info *mfi = file->private_data;
156         struct mtd_info *mtd = mfi->mtd;
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 (mfi->mode) {
190                 case MTD_MODE_OTP_FACTORY:
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                 case MTD_MODE_RAW:
197                 {
198                         struct mtd_oob_ops ops;
199
200                         ops.mode = MTD_OOB_RAW;
201                         ops.datbuf = kbuf;
202                         ops.oobbuf = NULL;
203                         ops.len = len;
204
205                         ret = mtd->read_oob(mtd, *ppos, &ops);
206                         retlen = ops.retlen;
207                         break;
208                 }
209                 default:
210                         ret = mtd->read(mtd, *ppos, len, &retlen, kbuf);
211                 }
212                 /* Nand returns -EBADMSG on ecc errors, but it returns
213                  * the data. For our userspace tools it is important
214                  * to dump areas with ecc errors !
215                  * For kernel internal usage it also might return -EUCLEAN
216                  * to signal the caller that a bitflip has occured and has
217                  * been corrected by the ECC algorithm.
218                  * Userspace software which accesses NAND this way
219                  * must be aware of the fact that it deals with NAND
220                  */
221                 if (!ret || (ret == -EUCLEAN) || (ret == -EBADMSG)) {
222                         *ppos += retlen;
223                         if (copy_to_user(buf, kbuf, retlen)) {
224                                 kfree(kbuf);
225                                 return -EFAULT;
226                         }
227                         else
228                                 total_retlen += retlen;
229
230                         count -= retlen;
231                         buf += retlen;
232                         if (retlen == 0)
233                                 count = 0;
234                 }
235                 else {
236                         kfree(kbuf);
237                         return ret;
238                 }
239
240         }
241
242         kfree(kbuf);
243         return total_retlen;
244 } /* mtd_read */
245
246 static ssize_t mtd_write(struct file *file, const char __user *buf, size_t count,loff_t *ppos)
247 {
248         struct mtd_file_info *mfi = file->private_data;
249         struct mtd_info *mtd = mfi->mtd;
250         char *kbuf;
251         size_t retlen;
252         size_t total_retlen=0;
253         int ret=0;
254         int len;
255
256         DEBUG(MTD_DEBUG_LEVEL0,"MTD_write\n");
257
258         if (*ppos == mtd->size)
259                 return -ENOSPC;
260
261         if (*ppos + count > mtd->size)
262                 count = mtd->size - *ppos;
263
264         if (!count)
265                 return 0;
266
267         if (count > MAX_KMALLOC_SIZE)
268                 kbuf=kmalloc(MAX_KMALLOC_SIZE, GFP_KERNEL);
269         else
270                 kbuf=kmalloc(count, GFP_KERNEL);
271
272         if (!kbuf)
273                 return -ENOMEM;
274
275         while (count) {
276
277                 if (count > MAX_KMALLOC_SIZE)
278                         len = MAX_KMALLOC_SIZE;
279                 else
280                         len = count;
281
282                 if (copy_from_user(kbuf, buf, len)) {
283                         kfree(kbuf);
284                         return -EFAULT;
285                 }
286
287                 switch (mfi->mode) {
288                 case MTD_MODE_OTP_FACTORY:
289                         ret = -EROFS;
290                         break;
291                 case MTD_MODE_OTP_USER:
292                         if (!mtd->write_user_prot_reg) {
293                                 ret = -EOPNOTSUPP;
294                                 break;
295                         }
296                         ret = mtd->write_user_prot_reg(mtd, *ppos, len, &retlen, kbuf);
297                         break;
298
299                 case MTD_MODE_RAW:
300                 {
301                         struct mtd_oob_ops ops;
302
303                         ops.mode = MTD_OOB_RAW;
304                         ops.datbuf = kbuf;
305                         ops.oobbuf = NULL;
306                         ops.len = len;
307
308                         ret = mtd->write_oob(mtd, *ppos, &ops);
309                         retlen = ops.retlen;
310                         break;
311                 }
312
313                 default:
314                         ret = (*(mtd->write))(mtd, *ppos, len, &retlen, kbuf);
315                 }
316                 if (!ret) {
317                         *ppos += retlen;
318                         total_retlen += retlen;
319                         count -= retlen;
320                         buf += retlen;
321                 }
322                 else {
323                         kfree(kbuf);
324                         return ret;
325                 }
326         }
327
328         kfree(kbuf);
329         return total_retlen;
330 } /* mtd_write */
331
332 /*======================================================================
333
334     IOCTL calls for getting device parameters.
335
336 ======================================================================*/
337 static void mtdchar_erase_callback (struct erase_info *instr)
338 {
339         wake_up((wait_queue_head_t *)instr->priv);
340 }
341
342 #if defined(CONFIG_MTD_OTP) || defined(CONFIG_MTD_ONENAND_OTP)
343 static int otp_select_filemode(struct mtd_file_info *mfi, int mode)
344 {
345         struct mtd_info *mtd = mfi->mtd;
346         int ret = 0;
347
348         switch (mode) {
349         case MTD_OTP_FACTORY:
350                 if (!mtd->read_fact_prot_reg)
351                         ret = -EOPNOTSUPP;
352                 else
353                         mfi->mode = MTD_MODE_OTP_FACTORY;
354                 break;
355         case MTD_OTP_USER:
356                 if (!mtd->read_fact_prot_reg)
357                         ret = -EOPNOTSUPP;
358                 else
359                         mfi->mode = MTD_MODE_OTP_USER;
360                 break;
361         default:
362                 ret = -EINVAL;
363         case MTD_OTP_OFF:
364                 break;
365         }
366         return ret;
367 }
368 #else
369 # define otp_select_filemode(f,m)       -EOPNOTSUPP
370 #endif
371
372 static int mtd_ioctl(struct inode *inode, struct file *file,
373                      u_int cmd, u_long arg)
374 {
375         struct mtd_file_info *mfi = file->private_data;
376         struct mtd_info *mtd = mfi->mtd;
377         void __user *argp = (void __user *)arg;
378         int ret = 0;
379         u_long size;
380         struct mtd_info_user info;
381
382         DEBUG(MTD_DEBUG_LEVEL0, "MTD_ioctl\n");
383
384         size = (cmd & IOCSIZE_MASK) >> IOCSIZE_SHIFT;
385         if (cmd & IOC_IN) {
386                 if (!access_ok(VERIFY_READ, argp, size))
387                         return -EFAULT;
388         }
389         if (cmd & IOC_OUT) {
390                 if (!access_ok(VERIFY_WRITE, argp, size))
391                         return -EFAULT;
392         }
393
394         switch (cmd) {
395         case MEMGETREGIONCOUNT:
396                 if (copy_to_user(argp, &(mtd->numeraseregions), sizeof(int)))
397                         return -EFAULT;
398                 break;
399
400         case MEMGETREGIONINFO:
401         {
402                 struct region_info_user ur;
403
404                 if (copy_from_user(&ur, argp, sizeof(struct region_info_user)))
405                         return -EFAULT;
406
407                 if (ur.regionindex >= mtd->numeraseregions)
408                         return -EINVAL;
409                 if (copy_to_user(argp, &(mtd->eraseregions[ur.regionindex]),
410                                 sizeof(struct mtd_erase_region_info)))
411                         return -EFAULT;
412                 break;
413         }
414
415         case MEMGETINFO:
416                 info.type       = mtd->type;
417                 info.flags      = mtd->flags;
418                 info.size       = mtd->size;
419                 info.erasesize  = mtd->erasesize;
420                 info.writesize  = mtd->writesize;
421                 info.oobsize    = mtd->oobsize;
422                 /* The below fields are obsolete */
423                 info.ecctype    = -1;
424                 info.eccsize    = 0;
425                 if (copy_to_user(argp, &info, sizeof(struct mtd_info_user)))
426                         return -EFAULT;
427                 break;
428
429         case MEMERASE:
430         {
431                 struct erase_info *erase;
432
433                 if(!(file->f_mode & 2))
434                         return -EPERM;
435
436                 erase=kzalloc(sizeof(struct erase_info),GFP_KERNEL);
437                 if (!erase)
438                         ret = -ENOMEM;
439                 else {
440                         wait_queue_head_t waitq;
441                         DECLARE_WAITQUEUE(wait, current);
442
443                         init_waitqueue_head(&waitq);
444
445                         if (copy_from_user(&erase->addr, argp,
446                                     sizeof(struct erase_info_user))) {
447                                 kfree(erase);
448                                 return -EFAULT;
449                         }
450                         erase->mtd = mtd;
451                         erase->callback = mtdchar_erase_callback;
452                         erase->priv = (unsigned long)&waitq;
453
454                         /*
455                           FIXME: Allow INTERRUPTIBLE. Which means
456                           not having the wait_queue head on the stack.
457
458                           If the wq_head is on the stack, and we
459                           leave because we got interrupted, then the
460                           wq_head is no longer there when the
461                           callback routine tries to wake us up.
462                         */
463                         ret = mtd->erase(mtd, erase);
464                         if (!ret) {
465                                 set_current_state(TASK_UNINTERRUPTIBLE);
466                                 add_wait_queue(&waitq, &wait);
467                                 if (erase->state != MTD_ERASE_DONE &&
468                                     erase->state != MTD_ERASE_FAILED)
469                                         schedule();
470                                 remove_wait_queue(&waitq, &wait);
471                                 set_current_state(TASK_RUNNING);
472
473                                 ret = (erase->state == MTD_ERASE_FAILED)?-EIO:0;
474                         }
475                         kfree(erase);
476                 }
477                 break;
478         }
479
480         case MEMWRITEOOB:
481         {
482                 struct mtd_oob_buf buf;
483                 struct mtd_oob_ops ops;
484
485                 if(!(file->f_mode & 2))
486                         return -EPERM;
487
488                 if (copy_from_user(&buf, argp, sizeof(struct mtd_oob_buf)))
489                         return -EFAULT;
490
491                 if (buf.length > 4096)
492                         return -EINVAL;
493
494                 if (!mtd->write_oob)
495                         ret = -EOPNOTSUPP;
496                 else
497                         ret = access_ok(VERIFY_READ, buf.ptr,
498                                         buf.length) ? 0 : EFAULT;
499
500                 if (ret)
501                         return ret;
502
503                 ops.ooblen = buf.length;
504                 ops.ooboffs = buf.start & (mtd->oobsize - 1);
505                 ops.datbuf = NULL;
506                 ops.mode = MTD_OOB_PLACE;
507
508                 if (ops.ooboffs && ops.ooblen > (mtd->oobsize - ops.ooboffs))
509                         return -EINVAL;
510
511                 ops.oobbuf = kmalloc(buf.length, GFP_KERNEL);
512                 if (!ops.oobbuf)
513                         return -ENOMEM;
514
515                 if (copy_from_user(ops.oobbuf, buf.ptr, buf.length)) {
516                         kfree(ops.oobbuf);
517                         return -EFAULT;
518                 }
519
520                 buf.start &= ~(mtd->oobsize - 1);
521                 ret = mtd->write_oob(mtd, buf.start, &ops);
522
523                 if (copy_to_user(argp + sizeof(uint32_t), &ops.oobretlen,
524                                  sizeof(uint32_t)))
525                         ret = -EFAULT;
526
527                 kfree(ops.oobbuf);
528                 break;
529
530         }
531
532         case MEMREADOOB:
533         {
534                 struct mtd_oob_buf buf;
535                 struct mtd_oob_ops ops;
536
537                 if (copy_from_user(&buf, argp, sizeof(struct mtd_oob_buf)))
538                         return -EFAULT;
539
540                 if (buf.length > 4096)
541                         return -EINVAL;
542
543                 if (!mtd->read_oob)
544                         ret = -EOPNOTSUPP;
545                 else
546                         ret = access_ok(VERIFY_WRITE, buf.ptr,
547                                         buf.length) ? 0 : -EFAULT;
548                 if (ret)
549                         return ret;
550
551                 ops.ooblen = buf.length;
552                 ops.ooboffs = buf.start & (mtd->oobsize - 1);
553                 ops.datbuf = NULL;
554                 ops.mode = MTD_OOB_PLACE;
555
556                 if (ops.ooboffs && ops.len > (mtd->oobsize - ops.ooboffs))
557                         return -EINVAL;
558
559                 ops.oobbuf = kmalloc(buf.length, GFP_KERNEL);
560                 if (!ops.oobbuf)
561                         return -ENOMEM;
562
563                 buf.start &= ~(mtd->oobsize - 1);
564                 ret = mtd->read_oob(mtd, buf.start, &ops);
565
566                 if (put_user(ops.oobretlen, (uint32_t __user *)argp))
567                         ret = -EFAULT;
568                 else if (ops.oobretlen && copy_to_user(buf.ptr, ops.oobbuf,
569                                                     ops.oobretlen))
570                         ret = -EFAULT;
571
572                 kfree(ops.oobbuf);
573                 break;
574         }
575
576         case MEMLOCK:
577         {
578                 struct erase_info_user info;
579
580                 if (copy_from_user(&info, argp, sizeof(info)))
581                         return -EFAULT;
582
583                 if (!mtd->lock)
584                         ret = -EOPNOTSUPP;
585                 else
586                         ret = mtd->lock(mtd, info.start, info.length);
587                 break;
588         }
589
590         case MEMUNLOCK:
591         {
592                 struct erase_info_user info;
593
594                 if (copy_from_user(&info, argp, sizeof(info)))
595                         return -EFAULT;
596
597                 if (!mtd->unlock)
598                         ret = -EOPNOTSUPP;
599                 else
600                         ret = mtd->unlock(mtd, info.start, info.length);
601                 break;
602         }
603
604         /* Legacy interface */
605         case MEMGETOOBSEL:
606         {
607                 struct nand_oobinfo oi;
608
609                 if (!mtd->ecclayout)
610                         return -EOPNOTSUPP;
611                 if (mtd->ecclayout->eccbytes > ARRAY_SIZE(oi.eccpos))
612                         return -EINVAL;
613
614                 oi.useecc = MTD_NANDECC_AUTOPLACE;
615                 memcpy(&oi.eccpos, mtd->ecclayout->eccpos, sizeof(oi.eccpos));
616                 memcpy(&oi.oobfree, mtd->ecclayout->oobfree,
617                        sizeof(oi.oobfree));
618                 oi.eccbytes = mtd->ecclayout->eccbytes;
619
620                 if (copy_to_user(argp, &oi, sizeof(struct nand_oobinfo)))
621                         return -EFAULT;
622                 break;
623         }
624
625         case MEMGETBADBLOCK:
626         {
627                 loff_t offs;
628
629                 if (copy_from_user(&offs, argp, sizeof(loff_t)))
630                         return -EFAULT;
631                 if (!mtd->block_isbad)
632                         ret = -EOPNOTSUPP;
633                 else
634                         return mtd->block_isbad(mtd, offs);
635                 break;
636         }
637
638         case MEMSETBADBLOCK:
639         {
640                 loff_t offs;
641
642                 if (copy_from_user(&offs, argp, sizeof(loff_t)))
643                         return -EFAULT;
644                 if (!mtd->block_markbad)
645                         ret = -EOPNOTSUPP;
646                 else
647                         return mtd->block_markbad(mtd, offs);
648                 break;
649         }
650
651 #if defined(CONFIG_MTD_OTP) || defined(CONFIG_MTD_ONENAND_OTP)
652         case OTPSELECT:
653         {
654                 int mode;
655                 if (copy_from_user(&mode, argp, sizeof(int)))
656                         return -EFAULT;
657
658                 mfi->mode = MTD_MODE_NORMAL;
659
660                 ret = otp_select_filemode(mfi, mode);
661
662                 file->f_pos = 0;
663                 break;
664         }
665
666         case OTPGETREGIONCOUNT:
667         case OTPGETREGIONINFO:
668         {
669                 struct otp_info *buf = kmalloc(4096, GFP_KERNEL);
670                 if (!buf)
671                         return -ENOMEM;
672                 ret = -EOPNOTSUPP;
673                 switch (mfi->mode) {
674                 case MTD_MODE_OTP_FACTORY:
675                         if (mtd->get_fact_prot_info)
676                                 ret = mtd->get_fact_prot_info(mtd, buf, 4096);
677                         break;
678                 case MTD_MODE_OTP_USER:
679                         if (mtd->get_user_prot_info)
680                                 ret = mtd->get_user_prot_info(mtd, buf, 4096);
681                         break;
682                 default:
683                         break;
684                 }
685                 if (ret >= 0) {
686                         if (cmd == OTPGETREGIONCOUNT) {
687                                 int nbr = ret / sizeof(struct otp_info);
688                                 ret = copy_to_user(argp, &nbr, sizeof(int));
689                         } else
690                                 ret = copy_to_user(argp, buf, ret);
691                         if (ret)
692                                 ret = -EFAULT;
693                 }
694                 kfree(buf);
695                 break;
696         }
697
698         case OTPLOCK:
699         {
700                 struct otp_info info;
701
702                 if (mfi->mode != MTD_MODE_OTP_USER)
703                         return -EINVAL;
704                 if (copy_from_user(&info, argp, sizeof(info)))
705                         return -EFAULT;
706                 if (!mtd->lock_user_prot_reg)
707                         return -EOPNOTSUPP;
708                 ret = mtd->lock_user_prot_reg(mtd, info.start, info.length);
709                 break;
710         }
711 #endif
712
713         case ECCGETLAYOUT:
714         {
715                 if (!mtd->ecclayout)
716                         return -EOPNOTSUPP;
717
718                 if (copy_to_user(argp, mtd->ecclayout,
719                                  sizeof(struct nand_ecclayout)))
720                         return -EFAULT;
721                 break;
722         }
723
724         case ECCGETSTATS:
725         {
726                 if (copy_to_user(argp, &mtd->ecc_stats,
727                                  sizeof(struct mtd_ecc_stats)))
728                         return -EFAULT;
729                 break;
730         }
731
732         case MTDFILEMODE:
733         {
734                 mfi->mode = 0;
735
736                 switch(arg) {
737                 case MTD_MODE_OTP_FACTORY:
738                 case MTD_MODE_OTP_USER:
739                         ret = otp_select_filemode(mfi, arg);
740                         break;
741
742                 case MTD_MODE_RAW:
743                         if (!mtd->read_oob || !mtd->write_oob)
744                                 return -EOPNOTSUPP;
745                         mfi->mode = arg;
746
747                 case MTD_MODE_NORMAL:
748                         break;
749                 default:
750                         ret = -EINVAL;
751                 }
752                 file->f_pos = 0;
753                 break;
754         }
755
756         default:
757                 ret = -ENOTTY;
758         }
759
760         return ret;
761 } /* memory_ioctl */
762
763 static const struct file_operations mtd_fops = {
764         .owner          = THIS_MODULE,
765         .llseek         = mtd_lseek,
766         .read           = mtd_read,
767         .write          = mtd_write,
768         .ioctl          = mtd_ioctl,
769         .open           = mtd_open,
770         .release        = mtd_close,
771 };
772
773 static int __init init_mtdchar(void)
774 {
775         if (register_chrdev(MTD_CHAR_MAJOR, "mtd", &mtd_fops)) {
776                 printk(KERN_NOTICE "Can't allocate major number %d for Memory Technology Devices.\n",
777                        MTD_CHAR_MAJOR);
778                 return -EAGAIN;
779         }
780
781         mtd_class = class_create(THIS_MODULE, "mtd");
782
783         if (IS_ERR(mtd_class)) {
784                 printk(KERN_ERR "Error creating mtd class.\n");
785                 unregister_chrdev(MTD_CHAR_MAJOR, "mtd");
786                 return PTR_ERR(mtd_class);
787         }
788
789         register_mtd_user(&notifier);
790         return 0;
791 }
792
793 static void __exit cleanup_mtdchar(void)
794 {
795         unregister_mtd_user(&notifier);
796         class_destroy(mtd_class);
797         unregister_chrdev(MTD_CHAR_MAJOR, "mtd");
798 }
799
800 module_init(init_mtdchar);
801 module_exit(cleanup_mtdchar);
802
803
804 MODULE_LICENSE("GPL");
805 MODULE_AUTHOR("David Woodhouse <dwmw2@infradead.org>");
806 MODULE_DESCRIPTION("Direct character-device access to MTD devices");