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Committer: Michael Beasley <mike@snafu.setup>
[mikesnafu-overlay.git] / drivers / mtd / mtdchar.c
blob5d3ac512ce169f1f4efc8de2cde7ae6ca21c6148
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/mm.h>
11 #include <linux/err.h>
12 #include <linux/init.h>
13 #include <linux/kernel.h>
14 #include <linux/module.h>
15 #include <linux/slab.h>
16 #include <linux/sched.h>
17
18 #include <linux/mtd/mtd.h>
19 #include <linux/mtd/compatmac.h>
20
21 #include <asm/uaccess.h>
22
23 static struct class *mtd_class;
24
25 static void mtd_notify_add(struct mtd_info* mtd)
26 {
27 if (!mtd)
28 return;
29
30 device_create(mtd_class, NULL, MKDEV(MTD_CHAR_MAJOR, mtd->index*2), "mtd%d", mtd->index);
31
32 device_create(mtd_class, NULL,
33 MKDEV(MTD_CHAR_MAJOR, mtd->index*2+1), "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 struct mtd_info *mtd;
90 struct mtd_file_info *mfi;
91
92 DEBUG(MTD_DEBUG_LEVEL0, "MTD_open\n");
93
94 if (devnum >= MAX_MTD_DEVICES)
95 return -ENODEV;
96
97 /* You can't open the RO devices RW */
98 if ((file->f_mode & 2) && (minor & 1))
99 return -EACCES;
100
101 mtd = get_mtd_device(NULL, devnum);
102
103 if (IS_ERR(mtd))
104 return PTR_ERR(mtd);
105
106 if (MTD_ABSENT == mtd->type) {
107 put_mtd_device(mtd);
108 return -ENODEV;
109 }
110
111 /* You can't open it RW if it's not a writeable device */
112 if ((file->f_mode & 2) && !(mtd->flags & MTD_WRITEABLE)) {
113 put_mtd_device(mtd);
114 return -EACCES;
115 }
116
117 mfi = kzalloc(sizeof(*mfi), GFP_KERNEL);
118 if (!mfi) {
119 put_mtd_device(mtd);
120 return -ENOMEM;
121 }
122 mfi->mtd = mtd;
123 file->private_data = mfi;
124
125 return 0;
126 } /* mtd_open */
127
128 /*====================================================================*/
129
130 static int mtd_close(struct inode *inode, struct file *file)
131 {
132 struct mtd_file_info *mfi = file->private_data;
133 struct mtd_info *mtd = mfi->mtd;
134
135 DEBUG(MTD_DEBUG_LEVEL0, "MTD_close\n");
136
137 /* Only sync if opened RW */
138 if ((file->f_mode & 2) && 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 uint32_t retlen;
485
486 if(!(file->f_mode & 2))
487 return -EPERM;
488
489 if (copy_from_user(&buf, argp, sizeof(struct mtd_oob_buf)))
490 return -EFAULT;
491
492 if (buf.length > 4096)
493 return -EINVAL;
494
495 if (!mtd->write_oob)
496 ret = -EOPNOTSUPP;
497 else
498 ret = access_ok(VERIFY_READ, buf.ptr,
499 buf.length) ? 0 : EFAULT;
500
501 if (ret)
502 return ret;
503
504 ops.ooblen = buf.length;
505 ops.ooboffs = buf.start & (mtd->oobsize - 1);
506 ops.datbuf = NULL;
507 ops.mode = MTD_OOB_PLACE;
508
509 if (ops.ooboffs && ops.ooblen > (mtd->oobsize - ops.ooboffs))
510 return -EINVAL;
511
512 ops.oobbuf = kmalloc(buf.length, GFP_KERNEL);
513 if (!ops.oobbuf)
514 return -ENOMEM;
515
516 if (copy_from_user(ops.oobbuf, buf.ptr, buf.length)) {
517 kfree(ops.oobbuf);
518 return -EFAULT;
519 }
520
521 buf.start &= ~(mtd->oobsize - 1);
522 ret = mtd->write_oob(mtd, buf.start, &ops);
523
524 if (ops.oobretlen > 0xFFFFFFFFU)
525 ret = -EOVERFLOW;
526 retlen = ops.oobretlen;
527 if (copy_to_user(&((struct mtd_oob_buf *)argp)->length,
528 &retlen, sizeof(buf.length)))
529 ret = -EFAULT;
530
531 kfree(ops.oobbuf);
532 break;
533
534 }
535
536 case MEMREADOOB:
537 {
538 struct mtd_oob_buf buf;
539 struct mtd_oob_ops ops;
540
541 if (copy_from_user(&buf, argp, sizeof(struct mtd_oob_buf)))
542 return -EFAULT;
543
544 if (buf.length > 4096)
545 return -EINVAL;
546
547 if (!mtd->read_oob)
548 ret = -EOPNOTSUPP;
549 else
550 ret = access_ok(VERIFY_WRITE, buf.ptr,
551 buf.length) ? 0 : -EFAULT;
552 if (ret)
553 return ret;
554
555 ops.ooblen = buf.length;
556 ops.ooboffs = buf.start & (mtd->oobsize - 1);
557 ops.datbuf = NULL;
558 ops.mode = MTD_OOB_PLACE;
559
560 if (ops.ooboffs && ops.ooblen > (mtd->oobsize - ops.ooboffs))
561 return -EINVAL;
562
563 ops.oobbuf = kmalloc(buf.length, GFP_KERNEL);
564 if (!ops.oobbuf)
565 return -ENOMEM;
566
567 buf.start &= ~(mtd->oobsize - 1);
568 ret = mtd->read_oob(mtd, buf.start, &ops);
569
570 if (put_user(ops.oobretlen, (uint32_t __user *)argp))
571 ret = -EFAULT;
572 else if (ops.oobretlen && copy_to_user(buf.ptr, ops.oobbuf,
573 ops.oobretlen))
574 ret = -EFAULT;
575
576 kfree(ops.oobbuf);
577 break;
578 }
579
580 case MEMLOCK:
581 {
582 struct erase_info_user info;
583
584 if (copy_from_user(&info, argp, sizeof(info)))
585 return -EFAULT;
586
587 if (!mtd->lock)
588 ret = -EOPNOTSUPP;
589 else
590 ret = mtd->lock(mtd, info.start, info.length);
591 break;
592 }
593
594 case MEMUNLOCK:
595 {
596 struct erase_info_user info;
597
598 if (copy_from_user(&info, argp, sizeof(info)))
599 return -EFAULT;
600
601 if (!mtd->unlock)
602 ret = -EOPNOTSUPP;
603 else
604 ret = mtd->unlock(mtd, info.start, info.length);
605 break;
606 }
607
608 /* Legacy interface */
609 case MEMGETOOBSEL:
610 {
611 struct nand_oobinfo oi;
612
613 if (!mtd->ecclayout)
614 return -EOPNOTSUPP;
615 if (mtd->ecclayout->eccbytes > ARRAY_SIZE(oi.eccpos))
616 return -EINVAL;
617
618 oi.useecc = MTD_NANDECC_AUTOPLACE;
619 memcpy(&oi.eccpos, mtd->ecclayout->eccpos, sizeof(oi.eccpos));
620 memcpy(&oi.oobfree, mtd->ecclayout->oobfree,
621 sizeof(oi.oobfree));
622 oi.eccbytes = mtd->ecclayout->eccbytes;
623
624 if (copy_to_user(argp, &oi, sizeof(struct nand_oobinfo)))
625 return -EFAULT;
626 break;
627 }
628
629 case MEMGETBADBLOCK:
630 {
631 loff_t offs;
632
633 if (copy_from_user(&offs, argp, sizeof(loff_t)))
634 return -EFAULT;
635 if (!mtd->block_isbad)
636 ret = -EOPNOTSUPP;
637 else
638 return mtd->block_isbad(mtd, offs);
639 break;
640 }
641
642 case MEMSETBADBLOCK:
643 {
644 loff_t offs;
645
646 if (copy_from_user(&offs, argp, sizeof(loff_t)))
647 return -EFAULT;
648 if (!mtd->block_markbad)
649 ret = -EOPNOTSUPP;
650 else
651 return mtd->block_markbad(mtd, offs);
652 break;
653 }
654
655 #if defined(CONFIG_MTD_OTP) || defined(CONFIG_MTD_ONENAND_OTP)
656 case OTPSELECT:
657 {
658 int mode;
659 if (copy_from_user(&mode, argp, sizeof(int)))
660 return -EFAULT;
661
662 mfi->mode = MTD_MODE_NORMAL;
663
664 ret = otp_select_filemode(mfi, mode);
665
666 file->f_pos = 0;
667 break;
668 }
669
670 case OTPGETREGIONCOUNT:
671 case OTPGETREGIONINFO:
672 {
673 struct otp_info *buf = kmalloc(4096, GFP_KERNEL);
674 if (!buf)
675 return -ENOMEM;
676 ret = -EOPNOTSUPP;
677 switch (mfi->mode) {
678 case MTD_MODE_OTP_FACTORY:
679 if (mtd->get_fact_prot_info)
680 ret = mtd->get_fact_prot_info(mtd, buf, 4096);
681 break;
682 case MTD_MODE_OTP_USER:
683 if (mtd->get_user_prot_info)
684 ret = mtd->get_user_prot_info(mtd, buf, 4096);
685 break;
686 default:
687 break;
688 }
689 if (ret >= 0) {
690 if (cmd == OTPGETREGIONCOUNT) {
691 int nbr = ret / sizeof(struct otp_info);
692 ret = copy_to_user(argp, &nbr, sizeof(int));
693 } else
694 ret = copy_to_user(argp, buf, ret);
695 if (ret)
696 ret = -EFAULT;
697 }
698 kfree(buf);
699 break;
700 }
701
702 case OTPLOCK:
703 {
704 struct otp_info info;
705
706 if (mfi->mode != MTD_MODE_OTP_USER)
707 return -EINVAL;
708 if (copy_from_user(&info, argp, sizeof(info)))
709 return -EFAULT;
710 if (!mtd->lock_user_prot_reg)
711 return -EOPNOTSUPP;
712 ret = mtd->lock_user_prot_reg(mtd, info.start, info.length);
713 break;
714 }
715 #endif
716
717 case ECCGETLAYOUT:
718 {
719 if (!mtd->ecclayout)
720 return -EOPNOTSUPP;
721
722 if (copy_to_user(argp, mtd->ecclayout,
723 sizeof(struct nand_ecclayout)))
724 return -EFAULT;
725 break;
726 }
727
728 case ECCGETSTATS:
729 {
730 if (copy_to_user(argp, &mtd->ecc_stats,
731 sizeof(struct mtd_ecc_stats)))
732 return -EFAULT;
733 break;
734 }
735
736 case MTDFILEMODE:
737 {
738 mfi->mode = 0;
739
740 switch(arg) {
741 case MTD_MODE_OTP_FACTORY:
742 case MTD_MODE_OTP_USER:
743 ret = otp_select_filemode(mfi, arg);
744 break;
745
746 case MTD_MODE_RAW:
747 if (!mtd->read_oob || !mtd->write_oob)
748 return -EOPNOTSUPP;
749 mfi->mode = arg;
750
751 case MTD_MODE_NORMAL:
752 break;
753 default:
754 ret = -EINVAL;
755 }
756 file->f_pos = 0;
757 break;
758 }
759
760 default:
761 ret = -ENOTTY;
762 }
763
764 return ret;
765 } /* memory_ioctl */
766
767 static const struct file_operations mtd_fops = {
768 .owner = THIS_MODULE,
769 .llseek = mtd_lseek,
770 .read = mtd_read,
771 .write = mtd_write,
772 .ioctl = mtd_ioctl,
773 .open = mtd_open,
774 .release = mtd_close,
775 };
776
777 static int __init init_mtdchar(void)
778 {
779 if (register_chrdev(MTD_CHAR_MAJOR, "mtd", &mtd_fops)) {
780 printk(KERN_NOTICE "Can't allocate major number %d for Memory Technology Devices.\n",
781 MTD_CHAR_MAJOR);
782 return -EAGAIN;
783 }
784
785 mtd_class = class_create(THIS_MODULE, "mtd");
786
787 if (IS_ERR(mtd_class)) {
788 printk(KERN_ERR "Error creating mtd class.\n");
789 unregister_chrdev(MTD_CHAR_MAJOR, "mtd");
790 return PTR_ERR(mtd_class);
791 }
792
793 register_mtd_user(&notifier);
794 return 0;
795 }
796
797 static void __exit cleanup_mtdchar(void)
798 {
799 unregister_mtd_user(&notifier);
800 class_destroy(mtd_class);
801 unregister_chrdev(MTD_CHAR_MAJOR, "mtd");
802 }
803
804 module_init(init_mtdchar);
805 module_exit(cleanup_mtdchar);
806
807
808 MODULE_LICENSE("GPL");
809 MODULE_AUTHOR("David Woodhouse <dwmw2@infradead.org>");
810 MODULE_DESCRIPTION("Direct character-device access to MTD devices");
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