2 * Core registration and callback routines for MTD
7 #include <linux/module.h>
8 #include <linux/kernel.h>
9 #include <linux/ptrace.h>
10 #include <linux/string.h>
11 #include <linux/timer.h>
12 #include <linux/major.h>
14 #include <linux/err.h>
15 #include <linux/ioctl.h>
16 #include <linux/init.h>
17 #include <linux/mtd/compatmac.h>
18 #include <linux/proc_fs.h>
20 #include <linux/mtd/mtd.h>
25 static int mtd_cls_suspend(struct device
*dev
, pm_message_t state
);
26 static int mtd_cls_resume(struct device
*dev
);
28 static struct class mtd_class
= {
31 .suspend
= mtd_cls_suspend
,
32 .resume
= mtd_cls_resume
,
35 /* These are exported solely for the purpose of mtd_blkdevs.c. You
36 should not use them for _anything_ else */
37 DEFINE_MUTEX(mtd_table_mutex
);
38 struct mtd_info
*mtd_table
[MAX_MTD_DEVICES
];
40 EXPORT_SYMBOL_GPL(mtd_table_mutex
);
41 EXPORT_SYMBOL_GPL(mtd_table
);
43 static LIST_HEAD(mtd_notifiers
);
46 #if defined(CONFIG_MTD_CHAR) || defined(CONFIG_MTD_CHAR_MODULE)
47 #define MTD_DEVT(index) MKDEV(MTD_CHAR_MAJOR, (index)*2)
49 #define MTD_DEVT(index) 0
52 /* REVISIT once MTD uses the driver model better, whoever allocates
53 * the mtd_info will probably want to use the release() hook...
55 static void mtd_release(struct device
*dev
)
57 dev_t index
= MTD_DEVT(dev_to_mtd(dev
)->index
);
59 /* remove /dev/mtdXro node if needed */
61 device_destroy(&mtd_class
, index
+ 1);
64 static int mtd_cls_suspend(struct device
*dev
, pm_message_t state
)
66 struct mtd_info
*mtd
= dev_to_mtd(dev
);
68 if (mtd
&& mtd
->suspend
)
69 return mtd
->suspend(mtd
);
74 static int mtd_cls_resume(struct device
*dev
)
76 struct mtd_info
*mtd
= dev_to_mtd(dev
);
78 if (mtd
&& mtd
->resume
)
83 static ssize_t
mtd_type_show(struct device
*dev
,
84 struct device_attribute
*attr
, char *buf
)
86 struct mtd_info
*mtd
= dev_to_mtd(dev
);
115 return snprintf(buf
, PAGE_SIZE
, "%s\n", type
);
117 static DEVICE_ATTR(type
, S_IRUGO
, mtd_type_show
, NULL
);
119 static ssize_t
mtd_flags_show(struct device
*dev
,
120 struct device_attribute
*attr
, char *buf
)
122 struct mtd_info
*mtd
= dev_to_mtd(dev
);
124 return snprintf(buf
, PAGE_SIZE
, "0x%lx\n", (unsigned long)mtd
->flags
);
127 static DEVICE_ATTR(flags
, S_IRUGO
, mtd_flags_show
, NULL
);
129 static ssize_t
mtd_size_show(struct device
*dev
,
130 struct device_attribute
*attr
, char *buf
)
132 struct mtd_info
*mtd
= dev_to_mtd(dev
);
134 return snprintf(buf
, PAGE_SIZE
, "%llu\n",
135 (unsigned long long)mtd
->size
);
138 static DEVICE_ATTR(size
, S_IRUGO
, mtd_size_show
, NULL
);
140 static ssize_t
mtd_erasesize_show(struct device
*dev
,
141 struct device_attribute
*attr
, char *buf
)
143 struct mtd_info
*mtd
= dev_to_mtd(dev
);
145 return snprintf(buf
, PAGE_SIZE
, "%lu\n", (unsigned long)mtd
->erasesize
);
148 static DEVICE_ATTR(erasesize
, S_IRUGO
, mtd_erasesize_show
, NULL
);
150 static ssize_t
mtd_writesize_show(struct device
*dev
,
151 struct device_attribute
*attr
, char *buf
)
153 struct mtd_info
*mtd
= dev_to_mtd(dev
);
155 return snprintf(buf
, PAGE_SIZE
, "%lu\n", (unsigned long)mtd
->writesize
);
158 static DEVICE_ATTR(writesize
, S_IRUGO
, mtd_writesize_show
, NULL
);
160 static ssize_t
mtd_subpagesize_show(struct device
*dev
,
161 struct device_attribute
*attr
, char *buf
)
163 struct mtd_info
*mtd
= dev_to_mtd(dev
);
164 unsigned int subpagesize
= mtd
->writesize
>> mtd
->subpage_sft
;
166 return snprintf(buf
, PAGE_SIZE
, "%u\n", subpagesize
);
169 static DEVICE_ATTR(subpagesize
, S_IRUGO
, mtd_subpagesize_show
, NULL
);
171 static ssize_t
mtd_oobsize_show(struct device
*dev
,
172 struct device_attribute
*attr
, char *buf
)
174 struct mtd_info
*mtd
= dev_to_mtd(dev
);
176 return snprintf(buf
, PAGE_SIZE
, "%lu\n", (unsigned long)mtd
->oobsize
);
179 static DEVICE_ATTR(oobsize
, S_IRUGO
, mtd_oobsize_show
, NULL
);
181 static ssize_t
mtd_numeraseregions_show(struct device
*dev
,
182 struct device_attribute
*attr
, char *buf
)
184 struct mtd_info
*mtd
= dev_to_mtd(dev
);
186 return snprintf(buf
, PAGE_SIZE
, "%u\n", mtd
->numeraseregions
);
189 static DEVICE_ATTR(numeraseregions
, S_IRUGO
, mtd_numeraseregions_show
,
192 static ssize_t
mtd_name_show(struct device
*dev
,
193 struct device_attribute
*attr
, char *buf
)
195 struct mtd_info
*mtd
= dev_to_mtd(dev
);
197 return snprintf(buf
, PAGE_SIZE
, "%s\n", mtd
->name
);
200 static DEVICE_ATTR(name
, S_IRUGO
, mtd_name_show
, NULL
);
202 static struct attribute
*mtd_attrs
[] = {
204 &dev_attr_flags
.attr
,
206 &dev_attr_erasesize
.attr
,
207 &dev_attr_writesize
.attr
,
208 &dev_attr_subpagesize
.attr
,
209 &dev_attr_oobsize
.attr
,
210 &dev_attr_numeraseregions
.attr
,
215 static struct attribute_group mtd_group
= {
219 static const struct attribute_group
*mtd_groups
[] = {
224 static struct device_type mtd_devtype
= {
226 .groups
= mtd_groups
,
227 .release
= mtd_release
,
231 * add_mtd_device - register an MTD device
232 * @mtd: pointer to new MTD device info structure
234 * Add a device to the list of MTD devices present in the system, and
235 * notify each currently active MTD 'user' of its arrival. Returns
236 * zero on success or 1 on failure, which currently will only happen
237 * if the number of present devices exceeds MAX_MTD_DEVICES (i.e. 16)
238 * or there's a sysfs error.
241 int add_mtd_device(struct mtd_info
*mtd
)
245 if (!mtd
->backing_dev_info
) {
248 mtd
->backing_dev_info
= &mtd_bdi_rw_mappable
;
251 mtd
->backing_dev_info
= &mtd_bdi_ro_mappable
;
254 mtd
->backing_dev_info
= &mtd_bdi_unmappable
;
259 BUG_ON(mtd
->writesize
== 0);
260 mutex_lock(&mtd_table_mutex
);
262 for (i
=0; i
< MAX_MTD_DEVICES
; i
++)
264 struct mtd_notifier
*not;
270 if (is_power_of_2(mtd
->erasesize
))
271 mtd
->erasesize_shift
= ffs(mtd
->erasesize
) - 1;
273 mtd
->erasesize_shift
= 0;
275 if (is_power_of_2(mtd
->writesize
))
276 mtd
->writesize_shift
= ffs(mtd
->writesize
) - 1;
278 mtd
->writesize_shift
= 0;
280 mtd
->erasesize_mask
= (1 << mtd
->erasesize_shift
) - 1;
281 mtd
->writesize_mask
= (1 << mtd
->writesize_shift
) - 1;
283 /* Some chips always power up locked. Unlock them now */
284 if ((mtd
->flags
& MTD_WRITEABLE
)
285 && (mtd
->flags
& MTD_POWERUP_LOCK
) && mtd
->unlock
) {
286 if (mtd
->unlock(mtd
, 0, mtd
->size
))
288 "%s: unlock failed, "
289 "writes may not work\n",
293 /* Caller should have set dev.parent to match the
296 mtd
->dev
.type
= &mtd_devtype
;
297 mtd
->dev
.class = &mtd_class
;
298 mtd
->dev
.devt
= MTD_DEVT(i
);
299 dev_set_name(&mtd
->dev
, "mtd%d", i
);
300 dev_set_drvdata(&mtd
->dev
, mtd
);
301 if (device_register(&mtd
->dev
) != 0) {
307 device_create(&mtd_class
, mtd
->dev
.parent
,
311 DEBUG(0, "mtd: Giving out device %d to %s\n",i
, mtd
->name
);
312 /* No need to get a refcount on the module containing
313 the notifier, since we hold the mtd_table_mutex */
314 list_for_each_entry(not, &mtd_notifiers
, list
)
317 mutex_unlock(&mtd_table_mutex
);
318 /* We _know_ we aren't being removed, because
319 our caller is still holding us here. So none
320 of this try_ nonsense, and no bitching about it
322 __module_get(THIS_MODULE
);
326 mutex_unlock(&mtd_table_mutex
);
331 * del_mtd_device - unregister an MTD device
332 * @mtd: pointer to MTD device info structure
334 * Remove a device from the list of MTD devices present in the system,
335 * and notify each currently active MTD 'user' of its departure.
336 * Returns zero on success or 1 on failure, which currently will happen
337 * if the requested device does not appear to be present in the list.
340 int del_mtd_device (struct mtd_info
*mtd
)
344 mutex_lock(&mtd_table_mutex
);
346 if (mtd_table
[mtd
->index
] != mtd
) {
348 } else if (mtd
->usecount
) {
349 printk(KERN_NOTICE
"Removing MTD device #%d (%s) with use count %d\n",
350 mtd
->index
, mtd
->name
, mtd
->usecount
);
353 struct mtd_notifier
*not;
355 device_unregister(&mtd
->dev
);
357 /* No need to get a refcount on the module containing
358 the notifier, since we hold the mtd_table_mutex */
359 list_for_each_entry(not, &mtd_notifiers
, list
)
362 mtd_table
[mtd
->index
] = NULL
;
364 module_put(THIS_MODULE
);
368 mutex_unlock(&mtd_table_mutex
);
373 * register_mtd_user - register a 'user' of MTD devices.
374 * @new: pointer to notifier info structure
376 * Registers a pair of callbacks function to be called upon addition
377 * or removal of MTD devices. Causes the 'add' callback to be immediately
378 * invoked for each MTD device currently present in the system.
381 void register_mtd_user (struct mtd_notifier
*new)
385 mutex_lock(&mtd_table_mutex
);
387 list_add(&new->list
, &mtd_notifiers
);
389 __module_get(THIS_MODULE
);
391 for (i
=0; i
< MAX_MTD_DEVICES
; i
++)
393 new->add(mtd_table
[i
]);
395 mutex_unlock(&mtd_table_mutex
);
399 * unregister_mtd_user - unregister a 'user' of MTD devices.
400 * @old: pointer to notifier info structure
402 * Removes a callback function pair from the list of 'users' to be
403 * notified upon addition or removal of MTD devices. Causes the
404 * 'remove' callback to be immediately invoked for each MTD device
405 * currently present in the system.
408 int unregister_mtd_user (struct mtd_notifier
*old
)
412 mutex_lock(&mtd_table_mutex
);
414 module_put(THIS_MODULE
);
416 for (i
=0; i
< MAX_MTD_DEVICES
; i
++)
418 old
->remove(mtd_table
[i
]);
420 list_del(&old
->list
);
421 mutex_unlock(&mtd_table_mutex
);
427 * get_mtd_device - obtain a validated handle for an MTD device
428 * @mtd: last known address of the required MTD device
429 * @num: internal device number of the required MTD device
431 * Given a number and NULL address, return the num'th entry in the device
432 * table, if any. Given an address and num == -1, search the device table
433 * for a device with that address and return if it's still present. Given
434 * both, return the num'th driver only if its address matches. Return
438 struct mtd_info
*get_mtd_device(struct mtd_info
*mtd
, int num
)
440 struct mtd_info
*ret
= NULL
;
441 int i
, err
= -ENODEV
;
443 mutex_lock(&mtd_table_mutex
);
446 for (i
=0; i
< MAX_MTD_DEVICES
; i
++)
447 if (mtd_table
[i
] == mtd
)
449 } else if (num
>= 0 && num
< MAX_MTD_DEVICES
) {
450 ret
= mtd_table
[num
];
451 if (mtd
&& mtd
!= ret
)
458 if (!try_module_get(ret
->owner
))
461 if (ret
->get_device
) {
462 err
= ret
->get_device(ret
);
468 mutex_unlock(&mtd_table_mutex
);
472 module_put(ret
->owner
);
474 mutex_unlock(&mtd_table_mutex
);
479 * get_mtd_device_nm - obtain a validated handle for an MTD device by
481 * @name: MTD device name to open
483 * This function returns MTD device description structure in case of
484 * success and an error code in case of failure.
487 struct mtd_info
*get_mtd_device_nm(const char *name
)
489 int i
, err
= -ENODEV
;
490 struct mtd_info
*mtd
= NULL
;
492 mutex_lock(&mtd_table_mutex
);
494 for (i
= 0; i
< MAX_MTD_DEVICES
; i
++) {
495 if (mtd_table
[i
] && !strcmp(name
, mtd_table
[i
]->name
)) {
504 if (!try_module_get(mtd
->owner
))
507 if (mtd
->get_device
) {
508 err
= mtd
->get_device(mtd
);
514 mutex_unlock(&mtd_table_mutex
);
518 module_put(mtd
->owner
);
520 mutex_unlock(&mtd_table_mutex
);
524 void put_mtd_device(struct mtd_info
*mtd
)
528 mutex_lock(&mtd_table_mutex
);
531 mtd
->put_device(mtd
);
532 mutex_unlock(&mtd_table_mutex
);
535 module_put(mtd
->owner
);
538 /* default_mtd_writev - default mtd writev method for MTD devices that
539 * don't implement their own
542 int default_mtd_writev(struct mtd_info
*mtd
, const struct kvec
*vecs
,
543 unsigned long count
, loff_t to
, size_t *retlen
)
546 size_t totlen
= 0, thislen
;
552 for (i
=0; i
<count
; i
++) {
553 if (!vecs
[i
].iov_len
)
555 ret
= mtd
->write(mtd
, to
, vecs
[i
].iov_len
, &thislen
, vecs
[i
].iov_base
);
557 if (ret
|| thislen
!= vecs
[i
].iov_len
)
559 to
+= vecs
[i
].iov_len
;
567 EXPORT_SYMBOL_GPL(add_mtd_device
);
568 EXPORT_SYMBOL_GPL(del_mtd_device
);
569 EXPORT_SYMBOL_GPL(get_mtd_device
);
570 EXPORT_SYMBOL_GPL(get_mtd_device_nm
);
571 EXPORT_SYMBOL_GPL(put_mtd_device
);
572 EXPORT_SYMBOL_GPL(register_mtd_user
);
573 EXPORT_SYMBOL_GPL(unregister_mtd_user
);
574 EXPORT_SYMBOL_GPL(default_mtd_writev
);
576 #ifdef CONFIG_PROC_FS
578 /*====================================================================*/
579 /* Support for /proc/mtd */
581 static struct proc_dir_entry
*proc_mtd
;
583 static inline int mtd_proc_info (char *buf
, int i
)
585 struct mtd_info
*this = mtd_table
[i
];
590 return sprintf(buf
, "mtd%d: %8.8llx %8.8x \"%s\"\n", i
,
591 (unsigned long long)this->size
,
592 this->erasesize
, this->name
);
595 static int mtd_read_proc (char *page
, char **start
, off_t off
, int count
,
596 int *eof
, void *data_unused
)
601 mutex_lock(&mtd_table_mutex
);
603 len
= sprintf(page
, "dev: size erasesize name\n");
604 for (i
=0; i
< MAX_MTD_DEVICES
; i
++) {
606 l
= mtd_proc_info(page
+ len
, i
);
608 if (len
+begin
> off
+count
)
610 if (len
+begin
< off
) {
619 mutex_unlock(&mtd_table_mutex
);
620 if (off
>= len
+begin
)
622 *start
= page
+ (off
-begin
);
623 return ((count
< begin
+len
-off
) ? count
: begin
+len
-off
);
626 #endif /* CONFIG_PROC_FS */
628 /*====================================================================*/
631 static int __init
init_mtd(void)
634 ret
= class_register(&mtd_class
);
637 pr_err("Error registering mtd class: %d\n", ret
);
640 #ifdef CONFIG_PROC_FS
641 if ((proc_mtd
= create_proc_entry( "mtd", 0, NULL
)))
642 proc_mtd
->read_proc
= mtd_read_proc
;
643 #endif /* CONFIG_PROC_FS */
647 static void __exit
cleanup_mtd(void)
649 #ifdef CONFIG_PROC_FS
651 remove_proc_entry( "mtd", NULL
);
652 #endif /* CONFIG_PROC_FS */
653 class_unregister(&mtd_class
);
656 module_init(init_mtd
);
657 module_exit(cleanup_mtd
);
659 MODULE_LICENSE("GPL");
660 MODULE_AUTHOR("David Woodhouse <dwmw2@infradead.org>");
661 MODULE_DESCRIPTION("Core MTD registration and access routines");