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percpu_counter: FBC_BATCH should be a variable
[linux-2.6/mini2440.git] / drivers / mtd / mtdchar.c
blobbcffeda2df3d680babc66906151dd3641ec57208
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 wait_queue_head_t waitq;
454 DECLARE_WAITQUEUE(wait, current);
455
456 init_waitqueue_head(&waitq);
457
458 if (copy_from_user(&erase->addr, argp,
459 sizeof(struct erase_info_user))) {
460 kfree(erase);
461 return -EFAULT;
462 }
463 erase->mtd = mtd;
464 erase->callback = mtdchar_erase_callback;
465 erase->priv = (unsigned long)&waitq;
466
467 /*
468 FIXME: Allow INTERRUPTIBLE. Which means
469 not having the wait_queue head on the stack.
470
471 If the wq_head is on the stack, and we
472 leave because we got interrupted, then the
473 wq_head is no longer there when the
474 callback routine tries to wake us up.
475 */
476 ret = mtd->erase(mtd, erase);
477 if (!ret) {
478 set_current_state(TASK_UNINTERRUPTIBLE);
479 add_wait_queue(&waitq, &wait);
480 if (erase->state != MTD_ERASE_DONE &&
481 erase->state != MTD_ERASE_FAILED)
482 schedule();
483 remove_wait_queue(&waitq, &wait);
484 set_current_state(TASK_RUNNING);
485
486 ret = (erase->state == MTD_ERASE_FAILED)?-EIO:0;
487 }
488 kfree(erase);
489 }
490 break;
491 }
492
493 case MEMWRITEOOB:
494 {
495 struct mtd_oob_buf buf;
496 struct mtd_oob_ops ops;
497 struct mtd_oob_buf __user *user_buf = argp;
498 uint32_t retlen;
499
500 if(!(file->f_mode & FMODE_WRITE))
501 return -EPERM;
502
503 if (copy_from_user(&buf, argp, sizeof(struct mtd_oob_buf)))
504 return -EFAULT;
505
506 if (buf.length > 4096)
507 return -EINVAL;
508
509 if (!mtd->write_oob)
510 ret = -EOPNOTSUPP;
511 else
512 ret = access_ok(VERIFY_READ, buf.ptr,
513 buf.length) ? 0 : EFAULT;
514
515 if (ret)
516 return ret;
517
518 ops.ooblen = buf.length;
519 ops.ooboffs = buf.start & (mtd->oobsize - 1);
520 ops.datbuf = NULL;
521 ops.mode = MTD_OOB_PLACE;
522
523 if (ops.ooboffs && ops.ooblen > (mtd->oobsize - ops.ooboffs))
524 return -EINVAL;
525
526 ops.oobbuf = kmalloc(buf.length, GFP_KERNEL);
527 if (!ops.oobbuf)
528 return -ENOMEM;
529
530 if (copy_from_user(ops.oobbuf, buf.ptr, buf.length)) {
531 kfree(ops.oobbuf);
532 return -EFAULT;
533 }
534
535 buf.start &= ~(mtd->oobsize - 1);
536 ret = mtd->write_oob(mtd, buf.start, &ops);
537
538 if (ops.oobretlen > 0xFFFFFFFFU)
539 ret = -EOVERFLOW;
540 retlen = ops.oobretlen;
541 if (copy_to_user(&user_buf->length, &retlen, sizeof(buf.length)))
542 ret = -EFAULT;
543
544 kfree(ops.oobbuf);
545 break;
546
547 }
548
549 case MEMREADOOB:
550 {
551 struct mtd_oob_buf buf;
552 struct mtd_oob_ops ops;
553
554 if (copy_from_user(&buf, argp, sizeof(struct mtd_oob_buf)))
555 return -EFAULT;
556
557 if (buf.length > 4096)
558 return -EINVAL;
559
560 if (!mtd->read_oob)
561 ret = -EOPNOTSUPP;
562 else
563 ret = access_ok(VERIFY_WRITE, buf.ptr,
564 buf.length) ? 0 : -EFAULT;
565 if (ret)
566 return ret;
567
568 ops.ooblen = buf.length;
569 ops.ooboffs = buf.start & (mtd->oobsize - 1);
570 ops.datbuf = NULL;
571 ops.mode = MTD_OOB_PLACE;
572
573 if (ops.ooboffs && ops.ooblen > (mtd->oobsize - ops.ooboffs))
574 return -EINVAL;
575
576 ops.oobbuf = kmalloc(buf.length, GFP_KERNEL);
577 if (!ops.oobbuf)
578 return -ENOMEM;
579
580 buf.start &= ~(mtd->oobsize - 1);
581 ret = mtd->read_oob(mtd, buf.start, &ops);
582
583 if (put_user(ops.oobretlen, (uint32_t __user *)argp))
584 ret = -EFAULT;
585 else if (ops.oobretlen && copy_to_user(buf.ptr, ops.oobbuf,
586 ops.oobretlen))
587 ret = -EFAULT;
588
589 kfree(ops.oobbuf);
590 break;
591 }
592
593 case MEMLOCK:
594 {
595 struct erase_info_user einfo;
596
597 if (copy_from_user(&einfo, argp, sizeof(einfo)))
598 return -EFAULT;
599
600 if (!mtd->lock)
601 ret = -EOPNOTSUPP;
602 else
603 ret = mtd->lock(mtd, einfo.start, einfo.length);
604 break;
605 }
606
607 case MEMUNLOCK:
608 {
609 struct erase_info_user einfo;
610
611 if (copy_from_user(&einfo, argp, sizeof(einfo)))
612 return -EFAULT;
613
614 if (!mtd->unlock)
615 ret = -EOPNOTSUPP;
616 else
617 ret = mtd->unlock(mtd, einfo.start, einfo.length);
618 break;
619 }
620
621 /* Legacy interface */
622 case MEMGETOOBSEL:
623 {
624 struct nand_oobinfo oi;
625
626 if (!mtd->ecclayout)
627 return -EOPNOTSUPP;
628 if (mtd->ecclayout->eccbytes > ARRAY_SIZE(oi.eccpos))
629 return -EINVAL;
630
631 oi.useecc = MTD_NANDECC_AUTOPLACE;
632 memcpy(&oi.eccpos, mtd->ecclayout->eccpos, sizeof(oi.eccpos));
633 memcpy(&oi.oobfree, mtd->ecclayout->oobfree,
634 sizeof(oi.oobfree));
635 oi.eccbytes = mtd->ecclayout->eccbytes;
636
637 if (copy_to_user(argp, &oi, sizeof(struct nand_oobinfo)))
638 return -EFAULT;
639 break;
640 }
641
642 case MEMGETBADBLOCK:
643 {
644 loff_t offs;
645
646 if (copy_from_user(&offs, argp, sizeof(loff_t)))
647 return -EFAULT;
648 if (!mtd->block_isbad)
649 ret = -EOPNOTSUPP;
650 else
651 return mtd->block_isbad(mtd, offs);
652 break;
653 }
654
655 case MEMSETBADBLOCK:
656 {
657 loff_t offs;
658
659 if (copy_from_user(&offs, argp, sizeof(loff_t)))
660 return -EFAULT;
661 if (!mtd->block_markbad)
662 ret = -EOPNOTSUPP;
663 else
664 return mtd->block_markbad(mtd, offs);
665 break;
666 }
667
668 #ifdef CONFIG_HAVE_MTD_OTP
669 case OTPSELECT:
670 {
671 int mode;
672 if (copy_from_user(&mode, argp, sizeof(int)))
673 return -EFAULT;
674
675 mfi->mode = MTD_MODE_NORMAL;
676
677 ret = otp_select_filemode(mfi, mode);
678
679 file->f_pos = 0;
680 break;
681 }
682
683 case OTPGETREGIONCOUNT:
684 case OTPGETREGIONINFO:
685 {
686 struct otp_info *buf = kmalloc(4096, GFP_KERNEL);
687 if (!buf)
688 return -ENOMEM;
689 ret = -EOPNOTSUPP;
690 switch (mfi->mode) {
691 case MTD_MODE_OTP_FACTORY:
692 if (mtd->get_fact_prot_info)
693 ret = mtd->get_fact_prot_info(mtd, buf, 4096);
694 break;
695 case MTD_MODE_OTP_USER:
696 if (mtd->get_user_prot_info)
697 ret = mtd->get_user_prot_info(mtd, buf, 4096);
698 break;
699 default:
700 break;
701 }
702 if (ret >= 0) {
703 if (cmd == OTPGETREGIONCOUNT) {
704 int nbr = ret / sizeof(struct otp_info);
705 ret = copy_to_user(argp, &nbr, sizeof(int));
706 } else
707 ret = copy_to_user(argp, buf, ret);
708 if (ret)
709 ret = -EFAULT;
710 }
711 kfree(buf);
712 break;
713 }
714
715 case OTPLOCK:
716 {
717 struct otp_info oinfo;
718
719 if (mfi->mode != MTD_MODE_OTP_USER)
720 return -EINVAL;
721 if (copy_from_user(&oinfo, argp, sizeof(oinfo)))
722 return -EFAULT;
723 if (!mtd->lock_user_prot_reg)
724 return -EOPNOTSUPP;
725 ret = mtd->lock_user_prot_reg(mtd, oinfo.start, oinfo.length);
726 break;
727 }
728 #endif
729
730 case ECCGETLAYOUT:
731 {
732 if (!mtd->ecclayout)
733 return -EOPNOTSUPP;
734
735 if (copy_to_user(argp, mtd->ecclayout,
736 sizeof(struct nand_ecclayout)))
737 return -EFAULT;
738 break;
739 }
740
741 case ECCGETSTATS:
742 {
743 if (copy_to_user(argp, &mtd->ecc_stats,
744 sizeof(struct mtd_ecc_stats)))
745 return -EFAULT;
746 break;
747 }
748
749 case MTDFILEMODE:
750 {
751 mfi->mode = 0;
752
753 switch(arg) {
754 case MTD_MODE_OTP_FACTORY:
755 case MTD_MODE_OTP_USER:
756 ret = otp_select_filemode(mfi, arg);
757 break;
758
759 case MTD_MODE_RAW:
760 if (!mtd->read_oob || !mtd->write_oob)
761 return -EOPNOTSUPP;
762 mfi->mode = arg;
763
764 case MTD_MODE_NORMAL:
765 break;
766 default:
767 ret = -EINVAL;
768 }
769 file->f_pos = 0;
770 break;
771 }
772
773 default:
774 ret = -ENOTTY;
775 }
776
777 return ret;
778 } /* memory_ioctl */
779
780 static const struct file_operations mtd_fops = {
781 .owner = THIS_MODULE,
782 .llseek = mtd_lseek,
783 .read = mtd_read,
784 .write = mtd_write,
785 .ioctl = mtd_ioctl,
786 .open = mtd_open,
787 .release = mtd_close,
788 };
789
790 static int __init init_mtdchar(void)
791 {
792 if (register_chrdev(MTD_CHAR_MAJOR, "mtd", &mtd_fops)) {
793 printk(KERN_NOTICE "Can't allocate major number %d for Memory Technology Devices.\n",
794 MTD_CHAR_MAJOR);
795 return -EAGAIN;
796 }
797
798 mtd_class = class_create(THIS_MODULE, "mtd");
799
800 if (IS_ERR(mtd_class)) {
801 printk(KERN_ERR "Error creating mtd class.\n");
802 unregister_chrdev(MTD_CHAR_MAJOR, "mtd");
803 return PTR_ERR(mtd_class);
804 }
805
806 register_mtd_user(&notifier);
807 return 0;
808 }
809
810 static void __exit cleanup_mtdchar(void)
811 {
812 unregister_mtd_user(&notifier);
813 class_destroy(mtd_class);
814 unregister_chrdev(MTD_CHAR_MAJOR, "mtd");
815 }
816
817 module_init(init_mtdchar);
818 module_exit(cleanup_mtdchar);
819
820
821 MODULE_LICENSE("GPL");
822 MODULE_AUTHOR("David Woodhouse <dwmw2@infradead.org>");
823 MODULE_DESCRIPTION("Direct character-device access to MTD devices");
Support for the Chinese Samsung S3C2440 based development boards