Linux 2.6.20.7
[linux/fpc-iii.git] / drivers / mtd / mtdchar.c
blob3013d0883b97212eb4ff1ea80c655872ec8cef75
1 /*
2 * $Id: mtdchar.c,v 1.76 2005/11/07 11:14:20 gleixner Exp $
4 * Character-device access to raw MTD devices.
6 */
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>
17 #include <linux/mtd/mtd.h>
18 #include <linux/mtd/compatmac.h>
20 #include <asm/uaccess.h>
22 static struct class *mtd_class;
24 static void mtd_notify_add(struct mtd_info* mtd)
26 if (!mtd)
27 return;
29 class_device_create(mtd_class, NULL, MKDEV(MTD_CHAR_MAJOR, mtd->index*2),
30 NULL, "mtd%d", mtd->index);
32 class_device_create(mtd_class, NULL,
33 MKDEV(MTD_CHAR_MAJOR, mtd->index*2+1),
34 NULL, "mtd%dro", mtd->index);
37 static void mtd_notify_remove(struct mtd_info* mtd)
39 if (!mtd)
40 return;
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));
46 static struct mtd_notifier notifier = {
47 .add = mtd_notify_add,
48 .remove = mtd_notify_remove,
52 * Data structure to hold the pointer to the mtd device as well
53 * as mode information ofr various use cases.
55 struct mtd_file_info {
56 struct mtd_info *mtd;
57 enum mtd_file_modes mode;
60 static loff_t mtd_lseek (struct file *file, loff_t offset, int orig)
62 struct mtd_file_info *mfi = file->private_data;
63 struct mtd_info *mtd = mfi->mtd;
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;
78 if (offset >= 0 && offset <= mtd->size)
79 return file->f_pos = offset;
81 return -EINVAL;
86 static int mtd_open(struct inode *inode, struct file *file)
88 int minor = iminor(inode);
89 int devnum = minor >> 1;
90 struct mtd_info *mtd;
91 struct mtd_file_info *mfi;
93 DEBUG(MTD_DEBUG_LEVEL0, "MTD_open\n");
95 if (devnum >= MAX_MTD_DEVICES)
96 return -ENODEV;
98 /* You can't open the RO devices RW */
99 if ((file->f_mode & 2) && (minor & 1))
100 return -EACCES;
102 mtd = get_mtd_device(NULL, devnum);
104 if (IS_ERR(mtd))
105 return PTR_ERR(mtd);
107 if (MTD_ABSENT == mtd->type) {
108 put_mtd_device(mtd);
109 return -ENODEV;
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;
118 mfi = kzalloc(sizeof(*mfi), GFP_KERNEL);
119 if (!mfi) {
120 put_mtd_device(mtd);
121 return -ENOMEM;
123 mfi->mtd = mtd;
124 file->private_data = mfi;
126 return 0;
127 } /* mtd_open */
129 /*====================================================================*/
131 static int mtd_close(struct inode *inode, struct file *file)
133 struct mtd_file_info *mfi = file->private_data;
134 struct mtd_info *mtd = mfi->mtd;
136 DEBUG(MTD_DEBUG_LEVEL0, "MTD_close\n");
138 if (mtd->sync)
139 mtd->sync(mtd);
141 put_mtd_device(mtd);
142 file->private_data = NULL;
143 kfree(mfi);
145 return 0;
146 } /* mtd_close */
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.
151 #define MAX_KMALLOC_SIZE 0x20000
153 static ssize_t mtd_read(struct file *file, char __user *buf, size_t count,loff_t *ppos)
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;
163 DEBUG(MTD_DEBUG_LEVEL0,"MTD_read\n");
165 if (*ppos + count > mtd->size)
166 count = mtd->size - *ppos;
168 if (!count)
169 return 0;
171 /* FIXME: Use kiovec in 2.5 to lock down the user's buffers
172 and pass them directly to the MTD functions */
174 if (count > MAX_KMALLOC_SIZE)
175 kbuf=kmalloc(MAX_KMALLOC_SIZE, GFP_KERNEL);
176 else
177 kbuf=kmalloc(count, GFP_KERNEL);
179 if (!kbuf)
180 return -ENOMEM;
182 while (count) {
184 if (count > MAX_KMALLOC_SIZE)
185 len = MAX_KMALLOC_SIZE;
186 else
187 len = count;
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:
198 struct mtd_oob_ops ops;
200 ops.mode = MTD_OOB_RAW;
201 ops.datbuf = kbuf;
202 ops.oobbuf = NULL;
203 ops.len = len;
205 ret = mtd->read_oob(mtd, *ppos, &ops);
206 retlen = ops.retlen;
207 break;
209 default:
210 ret = mtd->read(mtd, *ppos, len, &retlen, kbuf);
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
221 if (!ret || (ret == -EUCLEAN) || (ret == -EBADMSG)) {
222 *ppos += retlen;
223 if (copy_to_user(buf, kbuf, retlen)) {
224 kfree(kbuf);
225 return -EFAULT;
227 else
228 total_retlen += retlen;
230 count -= retlen;
231 buf += retlen;
232 if (retlen == 0)
233 count = 0;
235 else {
236 kfree(kbuf);
237 return ret;
242 kfree(kbuf);
243 return total_retlen;
244 } /* mtd_read */
246 static ssize_t mtd_write(struct file *file, const char __user *buf, size_t count,loff_t *ppos)
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;
256 DEBUG(MTD_DEBUG_LEVEL0,"MTD_write\n");
258 if (*ppos == mtd->size)
259 return -ENOSPC;
261 if (*ppos + count > mtd->size)
262 count = mtd->size - *ppos;
264 if (!count)
265 return 0;
267 if (count > MAX_KMALLOC_SIZE)
268 kbuf=kmalloc(MAX_KMALLOC_SIZE, GFP_KERNEL);
269 else
270 kbuf=kmalloc(count, GFP_KERNEL);
272 if (!kbuf)
273 return -ENOMEM;
275 while (count) {
277 if (count > MAX_KMALLOC_SIZE)
278 len = MAX_KMALLOC_SIZE;
279 else
280 len = count;
282 if (copy_from_user(kbuf, buf, len)) {
283 kfree(kbuf);
284 return -EFAULT;
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;
296 ret = mtd->write_user_prot_reg(mtd, *ppos, len, &retlen, kbuf);
297 break;
299 case MTD_MODE_RAW:
301 struct mtd_oob_ops ops;
303 ops.mode = MTD_OOB_RAW;
304 ops.datbuf = kbuf;
305 ops.oobbuf = NULL;
306 ops.len = len;
308 ret = mtd->write_oob(mtd, *ppos, &ops);
309 retlen = ops.retlen;
310 break;
313 default:
314 ret = (*(mtd->write))(mtd, *ppos, len, &retlen, kbuf);
316 if (!ret) {
317 *ppos += retlen;
318 total_retlen += retlen;
319 count -= retlen;
320 buf += retlen;
322 else {
323 kfree(kbuf);
324 return ret;
328 kfree(kbuf);
329 return total_retlen;
330 } /* mtd_write */
332 /*======================================================================
334 IOCTL calls for getting device parameters.
336 ======================================================================*/
337 static void mtdchar_erase_callback (struct erase_info *instr)
339 wake_up((wait_queue_head_t *)instr->priv);
342 #if defined(CONFIG_MTD_OTP) || defined(CONFIG_MTD_ONENAND_OTP)
343 static int otp_select_filemode(struct mtd_file_info *mfi, int mode)
345 struct mtd_info *mtd = mfi->mtd;
346 int ret = 0;
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;
366 return ret;
368 #else
369 # define otp_select_filemode(f,m) -EOPNOTSUPP
370 #endif
372 static int mtd_ioctl(struct inode *inode, struct file *file,
373 u_int cmd, u_long arg)
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;
382 DEBUG(MTD_DEBUG_LEVEL0, "MTD_ioctl\n");
384 size = (cmd & IOCSIZE_MASK) >> IOCSIZE_SHIFT;
385 if (cmd & IOC_IN) {
386 if (!access_ok(VERIFY_READ, argp, size))
387 return -EFAULT;
389 if (cmd & IOC_OUT) {
390 if (!access_ok(VERIFY_WRITE, argp, size))
391 return -EFAULT;
394 switch (cmd) {
395 case MEMGETREGIONCOUNT:
396 if (copy_to_user(argp, &(mtd->numeraseregions), sizeof(int)))
397 return -EFAULT;
398 break;
400 case MEMGETREGIONINFO:
402 struct region_info_user ur;
404 if (copy_from_user(&ur, argp, sizeof(struct region_info_user)))
405 return -EFAULT;
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;
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 info.ecctype = mtd->ecctype;
423 info.eccsize = mtd->eccsize;
424 if (copy_to_user(argp, &info, sizeof(struct mtd_info_user)))
425 return -EFAULT;
426 break;
428 case MEMERASE:
430 struct erase_info *erase;
432 if(!(file->f_mode & 2))
433 return -EPERM;
435 erase=kzalloc(sizeof(struct erase_info),GFP_KERNEL);
436 if (!erase)
437 ret = -ENOMEM;
438 else {
439 wait_queue_head_t waitq;
440 DECLARE_WAITQUEUE(wait, current);
442 init_waitqueue_head(&waitq);
444 if (copy_from_user(&erase->addr, argp,
445 sizeof(struct erase_info_user))) {
446 kfree(erase);
447 return -EFAULT;
449 erase->mtd = mtd;
450 erase->callback = mtdchar_erase_callback;
451 erase->priv = (unsigned long)&waitq;
454 FIXME: Allow INTERRUPTIBLE. Which means
455 not having the wait_queue head on the stack.
457 If the wq_head is on the stack, and we
458 leave because we got interrupted, then the
459 wq_head is no longer there when the
460 callback routine tries to wake us up.
462 ret = mtd->erase(mtd, erase);
463 if (!ret) {
464 set_current_state(TASK_UNINTERRUPTIBLE);
465 add_wait_queue(&waitq, &wait);
466 if (erase->state != MTD_ERASE_DONE &&
467 erase->state != MTD_ERASE_FAILED)
468 schedule();
469 remove_wait_queue(&waitq, &wait);
470 set_current_state(TASK_RUNNING);
472 ret = (erase->state == MTD_ERASE_FAILED)?-EIO:0;
474 kfree(erase);
476 break;
479 case MEMWRITEOOB:
481 struct mtd_oob_buf buf;
482 struct mtd_oob_ops ops;
484 if(!(file->f_mode & 2))
485 return -EPERM;
487 if (copy_from_user(&buf, argp, sizeof(struct mtd_oob_buf)))
488 return -EFAULT;
490 if (buf.length > 4096)
491 return -EINVAL;
493 if (!mtd->write_oob)
494 ret = -EOPNOTSUPP;
495 else
496 ret = access_ok(VERIFY_READ, buf.ptr,
497 buf.length) ? 0 : EFAULT;
499 if (ret)
500 return ret;
502 ops.ooblen = buf.length;
503 ops.ooboffs = buf.start & (mtd->oobsize - 1);
504 ops.datbuf = NULL;
505 ops.mode = MTD_OOB_PLACE;
507 if (ops.ooboffs && ops.ooblen > (mtd->oobsize - ops.ooboffs))
508 return -EINVAL;
510 ops.oobbuf = kmalloc(buf.length, GFP_KERNEL);
511 if (!ops.oobbuf)
512 return -ENOMEM;
514 if (copy_from_user(ops.oobbuf, buf.ptr, buf.length)) {
515 kfree(ops.oobbuf);
516 return -EFAULT;
519 buf.start &= ~(mtd->oobsize - 1);
520 ret = mtd->write_oob(mtd, buf.start, &ops);
522 if (copy_to_user(argp + sizeof(uint32_t), &ops.oobretlen,
523 sizeof(uint32_t)))
524 ret = -EFAULT;
526 kfree(ops.oobbuf);
527 break;
531 case MEMREADOOB:
533 struct mtd_oob_buf buf;
534 struct mtd_oob_ops ops;
536 if (copy_from_user(&buf, argp, sizeof(struct mtd_oob_buf)))
537 return -EFAULT;
539 if (buf.length > 4096)
540 return -EINVAL;
542 if (!mtd->read_oob)
543 ret = -EOPNOTSUPP;
544 else
545 ret = access_ok(VERIFY_WRITE, buf.ptr,
546 buf.length) ? 0 : -EFAULT;
547 if (ret)
548 return ret;
550 ops.ooblen = buf.length;
551 ops.ooboffs = buf.start & (mtd->oobsize - 1);
552 ops.datbuf = NULL;
553 ops.mode = MTD_OOB_PLACE;
555 if (ops.ooboffs && ops.len > (mtd->oobsize - ops.ooboffs))
556 return -EINVAL;
558 ops.oobbuf = kmalloc(buf.length, GFP_KERNEL);
559 if (!ops.oobbuf)
560 return -ENOMEM;
562 buf.start &= ~(mtd->oobsize - 1);
563 ret = mtd->read_oob(mtd, buf.start, &ops);
565 if (put_user(ops.oobretlen, (uint32_t __user *)argp))
566 ret = -EFAULT;
567 else if (ops.oobretlen && copy_to_user(buf.ptr, ops.oobbuf,
568 ops.oobretlen))
569 ret = -EFAULT;
571 kfree(ops.oobbuf);
572 break;
575 case MEMLOCK:
577 struct erase_info_user info;
579 if (copy_from_user(&info, argp, sizeof(info)))
580 return -EFAULT;
582 if (!mtd->lock)
583 ret = -EOPNOTSUPP;
584 else
585 ret = mtd->lock(mtd, info.start, info.length);
586 break;
589 case MEMUNLOCK:
591 struct erase_info_user info;
593 if (copy_from_user(&info, argp, sizeof(info)))
594 return -EFAULT;
596 if (!mtd->unlock)
597 ret = -EOPNOTSUPP;
598 else
599 ret = mtd->unlock(mtd, info.start, info.length);
600 break;
603 /* Legacy interface */
604 case MEMGETOOBSEL:
606 struct nand_oobinfo oi;
608 if (!mtd->ecclayout)
609 return -EOPNOTSUPP;
610 if (mtd->ecclayout->eccbytes > ARRAY_SIZE(oi.eccpos))
611 return -EINVAL;
613 oi.useecc = MTD_NANDECC_AUTOPLACE;
614 memcpy(&oi.eccpos, mtd->ecclayout->eccpos, sizeof(oi.eccpos));
615 memcpy(&oi.oobfree, mtd->ecclayout->oobfree,
616 sizeof(oi.oobfree));
617 oi.eccbytes = mtd->ecclayout->eccbytes;
619 if (copy_to_user(argp, &oi, sizeof(struct nand_oobinfo)))
620 return -EFAULT;
621 break;
624 case MEMGETBADBLOCK:
626 loff_t offs;
628 if (copy_from_user(&offs, argp, sizeof(loff_t)))
629 return -EFAULT;
630 if (!mtd->block_isbad)
631 ret = -EOPNOTSUPP;
632 else
633 return mtd->block_isbad(mtd, offs);
634 break;
637 case MEMSETBADBLOCK:
639 loff_t offs;
641 if (copy_from_user(&offs, argp, sizeof(loff_t)))
642 return -EFAULT;
643 if (!mtd->block_markbad)
644 ret = -EOPNOTSUPP;
645 else
646 return mtd->block_markbad(mtd, offs);
647 break;
650 #if defined(CONFIG_MTD_OTP) || defined(CONFIG_MTD_ONENAND_OTP)
651 case OTPSELECT:
653 int mode;
654 if (copy_from_user(&mode, argp, sizeof(int)))
655 return -EFAULT;
657 mfi->mode = MTD_MODE_NORMAL;
659 ret = otp_select_filemode(mfi, mode);
661 file->f_pos = 0;
662 break;
665 case OTPGETREGIONCOUNT:
666 case OTPGETREGIONINFO:
668 struct otp_info *buf = kmalloc(4096, GFP_KERNEL);
669 if (!buf)
670 return -ENOMEM;
671 ret = -EOPNOTSUPP;
672 switch (mfi->mode) {
673 case MTD_MODE_OTP_FACTORY:
674 if (mtd->get_fact_prot_info)
675 ret = mtd->get_fact_prot_info(mtd, buf, 4096);
676 break;
677 case MTD_MODE_OTP_USER:
678 if (mtd->get_user_prot_info)
679 ret = mtd->get_user_prot_info(mtd, buf, 4096);
680 break;
681 default:
682 break;
684 if (ret >= 0) {
685 if (cmd == OTPGETREGIONCOUNT) {
686 int nbr = ret / sizeof(struct otp_info);
687 ret = copy_to_user(argp, &nbr, sizeof(int));
688 } else
689 ret = copy_to_user(argp, buf, ret);
690 if (ret)
691 ret = -EFAULT;
693 kfree(buf);
694 break;
697 case OTPLOCK:
699 struct otp_info info;
701 if (mfi->mode != MTD_MODE_OTP_USER)
702 return -EINVAL;
703 if (copy_from_user(&info, argp, sizeof(info)))
704 return -EFAULT;
705 if (!mtd->lock_user_prot_reg)
706 return -EOPNOTSUPP;
707 ret = mtd->lock_user_prot_reg(mtd, info.start, info.length);
708 break;
710 #endif
712 case ECCGETLAYOUT:
714 if (!mtd->ecclayout)
715 return -EOPNOTSUPP;
717 if (copy_to_user(argp, mtd->ecclayout,
718 sizeof(struct nand_ecclayout)))
719 return -EFAULT;
720 break;
723 case ECCGETSTATS:
725 if (copy_to_user(argp, &mtd->ecc_stats,
726 sizeof(struct mtd_ecc_stats)))
727 return -EFAULT;
728 break;
731 case MTDFILEMODE:
733 mfi->mode = 0;
735 switch(arg) {
736 case MTD_MODE_OTP_FACTORY:
737 case MTD_MODE_OTP_USER:
738 ret = otp_select_filemode(mfi, arg);
739 break;
741 case MTD_MODE_RAW:
742 if (!mtd->read_oob || !mtd->write_oob)
743 return -EOPNOTSUPP;
744 mfi->mode = arg;
746 case MTD_MODE_NORMAL:
747 break;
748 default:
749 ret = -EINVAL;
751 file->f_pos = 0;
752 break;
755 default:
756 ret = -ENOTTY;
759 return ret;
760 } /* memory_ioctl */
762 static struct file_operations mtd_fops = {
763 .owner = THIS_MODULE,
764 .llseek = mtd_lseek,
765 .read = mtd_read,
766 .write = mtd_write,
767 .ioctl = mtd_ioctl,
768 .open = mtd_open,
769 .release = mtd_close,
772 static int __init init_mtdchar(void)
774 if (register_chrdev(MTD_CHAR_MAJOR, "mtd", &mtd_fops)) {
775 printk(KERN_NOTICE "Can't allocate major number %d for Memory Technology Devices.\n",
776 MTD_CHAR_MAJOR);
777 return -EAGAIN;
780 mtd_class = class_create(THIS_MODULE, "mtd");
782 if (IS_ERR(mtd_class)) {
783 printk(KERN_ERR "Error creating mtd class.\n");
784 unregister_chrdev(MTD_CHAR_MAJOR, "mtd");
785 return PTR_ERR(mtd_class);
788 register_mtd_user(&notifier);
789 return 0;
792 static void __exit cleanup_mtdchar(void)
794 unregister_mtd_user(&notifier);
795 class_destroy(mtd_class);
796 unregister_chrdev(MTD_CHAR_MAJOR, "mtd");
799 module_init(init_mtdchar);
800 module_exit(cleanup_mtdchar);
803 MODULE_LICENSE("GPL");
804 MODULE_AUTHOR("David Woodhouse <dwmw2@infradead.org>");
805 MODULE_DESCRIPTION("Direct character-device access to MTD devices");