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Commit | Line | Data |
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1da177e4 LT |
1 | /* |
2 | * drivers/base/core.c - core driver model code (device registration, etc) | |
3 | * | |
4 | * Copyright (c) 2002-3 Patrick Mochel | |
5 | * Copyright (c) 2002-3 Open Source Development Labs | |
64bb5d2c GKH |
6 | * Copyright (c) 2006 Greg Kroah-Hartman <gregkh@suse.de> |
7 | * Copyright (c) 2006 Novell, Inc. | |
1da177e4 LT |
8 | * |
9 | * This file is released under the GPLv2 | |
10 | * | |
11 | */ | |
12 | ||
1da177e4 LT |
13 | #include <linux/device.h> |
14 | #include <linux/err.h> | |
15 | #include <linux/init.h> | |
16 | #include <linux/module.h> | |
17 | #include <linux/slab.h> | |
18 | #include <linux/string.h> | |
23681e47 | 19 | #include <linux/kdev_t.h> |
1da177e4 LT |
20 | |
21 | #include <asm/semaphore.h> | |
22 | ||
23 | #include "base.h" | |
24 | #include "power/power.h" | |
25 | ||
26 | int (*platform_notify)(struct device * dev) = NULL; | |
27 | int (*platform_notify_remove)(struct device * dev) = NULL; | |
28 | ||
29 | /* | |
30 | * sysfs bindings for devices. | |
31 | */ | |
32 | ||
3e95637a AS |
33 | /** |
34 | * dev_driver_string - Return a device's driver name, if at all possible | |
35 | * @dev: struct device to get the name of | |
36 | * | |
37 | * Will return the device's driver's name if it is bound to a device. If | |
38 | * the device is not bound to a device, it will return the name of the bus | |
39 | * it is attached to. If it is not attached to a bus either, an empty | |
40 | * string will be returned. | |
41 | */ | |
42 | const char *dev_driver_string(struct device *dev) | |
43 | { | |
44 | return dev->driver ? dev->driver->name : | |
45 | (dev->bus ? dev->bus->name : ""); | |
46 | } | |
47 | EXPORT_SYMBOL_GPL(dev_driver_string); | |
48 | ||
1da177e4 LT |
49 | #define to_dev(obj) container_of(obj, struct device, kobj) |
50 | #define to_dev_attr(_attr) container_of(_attr, struct device_attribute, attr) | |
51 | ||
1da177e4 LT |
52 | static ssize_t |
53 | dev_attr_show(struct kobject * kobj, struct attribute * attr, char * buf) | |
54 | { | |
55 | struct device_attribute * dev_attr = to_dev_attr(attr); | |
56 | struct device * dev = to_dev(kobj); | |
4a0c20bf | 57 | ssize_t ret = -EIO; |
1da177e4 LT |
58 | |
59 | if (dev_attr->show) | |
54b6f35c | 60 | ret = dev_attr->show(dev, dev_attr, buf); |
1da177e4 LT |
61 | return ret; |
62 | } | |
63 | ||
64 | static ssize_t | |
65 | dev_attr_store(struct kobject * kobj, struct attribute * attr, | |
66 | const char * buf, size_t count) | |
67 | { | |
68 | struct device_attribute * dev_attr = to_dev_attr(attr); | |
69 | struct device * dev = to_dev(kobj); | |
4a0c20bf | 70 | ssize_t ret = -EIO; |
1da177e4 LT |
71 | |
72 | if (dev_attr->store) | |
54b6f35c | 73 | ret = dev_attr->store(dev, dev_attr, buf, count); |
1da177e4 LT |
74 | return ret; |
75 | } | |
76 | ||
77 | static struct sysfs_ops dev_sysfs_ops = { | |
78 | .show = dev_attr_show, | |
79 | .store = dev_attr_store, | |
80 | }; | |
81 | ||
82 | ||
83 | /** | |
84 | * device_release - free device structure. | |
85 | * @kobj: device's kobject. | |
86 | * | |
87 | * This is called once the reference count for the object | |
88 | * reaches 0. We forward the call to the device's release | |
89 | * method, which should handle actually freeing the structure. | |
90 | */ | |
91 | static void device_release(struct kobject * kobj) | |
92 | { | |
93 | struct device * dev = to_dev(kobj); | |
94 | ||
95 | if (dev->release) | |
96 | dev->release(dev); | |
2620efef GKH |
97 | else if (dev->class && dev->class->dev_release) |
98 | dev->class->dev_release(dev); | |
1da177e4 LT |
99 | else { |
100 | printk(KERN_ERR "Device '%s' does not have a release() function, " | |
101 | "it is broken and must be fixed.\n", | |
102 | dev->bus_id); | |
103 | WARN_ON(1); | |
104 | } | |
105 | } | |
106 | ||
107 | static struct kobj_type ktype_device = { | |
108 | .release = device_release, | |
109 | .sysfs_ops = &dev_sysfs_ops, | |
1da177e4 LT |
110 | }; |
111 | ||
112 | ||
312c004d | 113 | static int dev_uevent_filter(struct kset *kset, struct kobject *kobj) |
1da177e4 LT |
114 | { |
115 | struct kobj_type *ktype = get_ktype(kobj); | |
116 | ||
117 | if (ktype == &ktype_device) { | |
118 | struct device *dev = to_dev(kobj); | |
119 | if (dev->bus) | |
120 | return 1; | |
23681e47 GKH |
121 | if (dev->class) |
122 | return 1; | |
1da177e4 LT |
123 | } |
124 | return 0; | |
125 | } | |
126 | ||
312c004d | 127 | static const char *dev_uevent_name(struct kset *kset, struct kobject *kobj) |
1da177e4 LT |
128 | { |
129 | struct device *dev = to_dev(kobj); | |
130 | ||
23681e47 GKH |
131 | if (dev->bus) |
132 | return dev->bus->name; | |
133 | if (dev->class) | |
134 | return dev->class->name; | |
135 | return NULL; | |
1da177e4 LT |
136 | } |
137 | ||
312c004d | 138 | static int dev_uevent(struct kset *kset, struct kobject *kobj, char **envp, |
1da177e4 LT |
139 | int num_envp, char *buffer, int buffer_size) |
140 | { | |
141 | struct device *dev = to_dev(kobj); | |
142 | int i = 0; | |
143 | int length = 0; | |
144 | int retval = 0; | |
145 | ||
23681e47 GKH |
146 | /* add the major/minor if present */ |
147 | if (MAJOR(dev->devt)) { | |
148 | add_uevent_var(envp, num_envp, &i, | |
149 | buffer, buffer_size, &length, | |
150 | "MAJOR=%u", MAJOR(dev->devt)); | |
151 | add_uevent_var(envp, num_envp, &i, | |
152 | buffer, buffer_size, &length, | |
153 | "MINOR=%u", MINOR(dev->devt)); | |
154 | } | |
155 | ||
d81d9d6b | 156 | /* add bus name (same as SUBSYSTEM, deprecated) */ |
1da177e4 | 157 | if (dev->bus) |
312c004d KS |
158 | add_uevent_var(envp, num_envp, &i, |
159 | buffer, buffer_size, &length, | |
160 | "PHYSDEVBUS=%s", dev->bus->name); | |
1da177e4 | 161 | |
d81d9d6b KS |
162 | /* add driver name (PHYSDEV* values are deprecated)*/ |
163 | if (dev->driver) { | |
164 | add_uevent_var(envp, num_envp, &i, | |
165 | buffer, buffer_size, &length, | |
166 | "DRIVER=%s", dev->driver->name); | |
312c004d KS |
167 | add_uevent_var(envp, num_envp, &i, |
168 | buffer, buffer_size, &length, | |
169 | "PHYSDEVDRIVER=%s", dev->driver->name); | |
d81d9d6b | 170 | } |
1da177e4 LT |
171 | |
172 | /* terminate, set to next free slot, shrink available space */ | |
173 | envp[i] = NULL; | |
174 | envp = &envp[i]; | |
175 | num_envp -= i; | |
176 | buffer = &buffer[length]; | |
177 | buffer_size -= length; | |
178 | ||
312c004d | 179 | if (dev->bus && dev->bus->uevent) { |
1da177e4 | 180 | /* have the bus specific function add its stuff */ |
312c004d | 181 | retval = dev->bus->uevent(dev, envp, num_envp, buffer, buffer_size); |
1da177e4 | 182 | if (retval) { |
312c004d | 183 | pr_debug ("%s - uevent() returned %d\n", |
1da177e4 LT |
184 | __FUNCTION__, retval); |
185 | } | |
186 | } | |
187 | ||
2620efef GKH |
188 | if (dev->class && dev->class->dev_uevent) { |
189 | /* have the class specific function add its stuff */ | |
190 | retval = dev->class->dev_uevent(dev, envp, num_envp, buffer, buffer_size); | |
191 | if (retval) { | |
192 | pr_debug("%s - dev_uevent() returned %d\n", | |
193 | __FUNCTION__, retval); | |
194 | } | |
195 | } | |
196 | ||
1da177e4 LT |
197 | return retval; |
198 | } | |
199 | ||
312c004d KS |
200 | static struct kset_uevent_ops device_uevent_ops = { |
201 | .filter = dev_uevent_filter, | |
202 | .name = dev_uevent_name, | |
203 | .uevent = dev_uevent, | |
1da177e4 LT |
204 | }; |
205 | ||
a7fd6706 KS |
206 | static ssize_t store_uevent(struct device *dev, struct device_attribute *attr, |
207 | const char *buf, size_t count) | |
208 | { | |
312c004d | 209 | kobject_uevent(&dev->kobj, KOBJ_ADD); |
a7fd6706 KS |
210 | return count; |
211 | } | |
212 | ||
de0ff00d GKH |
213 | static int device_add_groups(struct device *dev) |
214 | { | |
215 | int i; | |
216 | int error = 0; | |
217 | ||
218 | if (dev->groups) { | |
219 | for (i = 0; dev->groups[i]; i++) { | |
220 | error = sysfs_create_group(&dev->kobj, dev->groups[i]); | |
221 | if (error) { | |
222 | while (--i >= 0) | |
223 | sysfs_remove_group(&dev->kobj, dev->groups[i]); | |
224 | goto out; | |
225 | } | |
226 | } | |
227 | } | |
228 | out: | |
229 | return error; | |
230 | } | |
231 | ||
232 | static void device_remove_groups(struct device *dev) | |
233 | { | |
234 | int i; | |
235 | if (dev->groups) { | |
236 | for (i = 0; dev->groups[i]; i++) { | |
237 | sysfs_remove_group(&dev->kobj, dev->groups[i]); | |
238 | } | |
239 | } | |
240 | } | |
241 | ||
2620efef GKH |
242 | static int device_add_attrs(struct device *dev) |
243 | { | |
244 | struct class *class = dev->class; | |
245 | int error = 0; | |
246 | int i; | |
247 | ||
248 | if (!class) | |
249 | return 0; | |
250 | ||
251 | if (class->dev_attrs) { | |
252 | for (i = 0; attr_name(class->dev_attrs[i]); i++) { | |
253 | error = device_create_file(dev, &class->dev_attrs[i]); | |
254 | if (error) | |
255 | break; | |
256 | } | |
257 | } | |
258 | if (error) | |
259 | while (--i >= 0) | |
260 | device_remove_file(dev, &class->dev_attrs[i]); | |
261 | return error; | |
262 | } | |
263 | ||
264 | static void device_remove_attrs(struct device *dev) | |
265 | { | |
266 | struct class *class = dev->class; | |
267 | int i; | |
268 | ||
269 | if (!class) | |
270 | return; | |
271 | ||
272 | if (class->dev_attrs) { | |
273 | for (i = 0; attr_name(class->dev_attrs[i]); i++) | |
274 | device_remove_file(dev, &class->dev_attrs[i]); | |
275 | } | |
276 | } | |
277 | ||
278 | ||
23681e47 GKH |
279 | static ssize_t show_dev(struct device *dev, struct device_attribute *attr, |
280 | char *buf) | |
281 | { | |
282 | return print_dev_t(buf, dev->devt); | |
283 | } | |
284 | ||
0863afb3 MW |
285 | /* |
286 | * devices_subsys - structure to be registered with kobject core. | |
1da177e4 LT |
287 | */ |
288 | ||
312c004d | 289 | decl_subsys(devices, &ktype_device, &device_uevent_ops); |
1da177e4 LT |
290 | |
291 | ||
292 | /** | |
293 | * device_create_file - create sysfs attribute file for device. | |
294 | * @dev: device. | |
295 | * @attr: device attribute descriptor. | |
296 | */ | |
297 | ||
298 | int device_create_file(struct device * dev, struct device_attribute * attr) | |
299 | { | |
300 | int error = 0; | |
301 | if (get_device(dev)) { | |
302 | error = sysfs_create_file(&dev->kobj, &attr->attr); | |
303 | put_device(dev); | |
304 | } | |
305 | return error; | |
306 | } | |
307 | ||
308 | /** | |
309 | * device_remove_file - remove sysfs attribute file. | |
310 | * @dev: device. | |
311 | * @attr: device attribute descriptor. | |
312 | */ | |
313 | ||
314 | void device_remove_file(struct device * dev, struct device_attribute * attr) | |
315 | { | |
316 | if (get_device(dev)) { | |
317 | sysfs_remove_file(&dev->kobj, &attr->attr); | |
318 | put_device(dev); | |
319 | } | |
320 | } | |
321 | ||
34bb61f9 JB |
322 | static void klist_children_get(struct klist_node *n) |
323 | { | |
324 | struct device *dev = container_of(n, struct device, knode_parent); | |
325 | ||
326 | get_device(dev); | |
327 | } | |
328 | ||
329 | static void klist_children_put(struct klist_node *n) | |
330 | { | |
331 | struct device *dev = container_of(n, struct device, knode_parent); | |
332 | ||
333 | put_device(dev); | |
334 | } | |
335 | ||
1da177e4 LT |
336 | |
337 | /** | |
338 | * device_initialize - init device structure. | |
339 | * @dev: device. | |
340 | * | |
341 | * This prepares the device for use by other layers, | |
342 | * including adding it to the device hierarchy. | |
343 | * It is the first half of device_register(), if called by | |
344 | * that, though it can also be called separately, so one | |
345 | * may use @dev's fields (e.g. the refcount). | |
346 | */ | |
347 | ||
348 | void device_initialize(struct device *dev) | |
349 | { | |
350 | kobj_set_kset_s(dev, devices_subsys); | |
351 | kobject_init(&dev->kobj); | |
34bb61f9 JB |
352 | klist_init(&dev->klist_children, klist_children_get, |
353 | klist_children_put); | |
1da177e4 | 354 | INIT_LIST_HEAD(&dev->dma_pools); |
23681e47 | 355 | INIT_LIST_HEAD(&dev->node); |
af70316a | 356 | init_MUTEX(&dev->sem); |
0ac85241 | 357 | device_init_wakeup(dev, 0); |
1da177e4 LT |
358 | } |
359 | ||
360 | /** | |
361 | * device_add - add device to device hierarchy. | |
362 | * @dev: device. | |
363 | * | |
364 | * This is part 2 of device_register(), though may be called | |
365 | * separately _iff_ device_initialize() has been called separately. | |
366 | * | |
367 | * This adds it to the kobject hierarchy via kobject_add(), adds it | |
368 | * to the global and sibling lists for the device, then | |
369 | * adds it to the other relevant subsystems of the driver model. | |
370 | */ | |
371 | int device_add(struct device *dev) | |
372 | { | |
373 | struct device *parent = NULL; | |
e9a7d305 | 374 | char *class_name = NULL; |
c47ed219 | 375 | struct class_interface *class_intf; |
1da177e4 LT |
376 | int error = -EINVAL; |
377 | ||
378 | dev = get_device(dev); | |
379 | if (!dev || !strlen(dev->bus_id)) | |
380 | goto Error; | |
381 | ||
c205ef48 GKH |
382 | /* if this is a class device, and has no parent, create one */ |
383 | if ((dev->class) && (dev->parent == NULL)) { | |
384 | error = virtual_device_parent(dev); | |
385 | if (error) | |
386 | goto Error; | |
387 | } | |
388 | ||
1da177e4 LT |
389 | parent = get_device(dev->parent); |
390 | ||
391 | pr_debug("DEV: registering device: ID = '%s'\n", dev->bus_id); | |
392 | ||
393 | /* first, register with generic layer. */ | |
394 | kobject_set_name(&dev->kobj, "%s", dev->bus_id); | |
395 | if (parent) | |
396 | dev->kobj.parent = &parent->kobj; | |
397 | ||
398 | if ((error = kobject_add(&dev->kobj))) | |
399 | goto Error; | |
a7fd6706 KS |
400 | |
401 | dev->uevent_attr.attr.name = "uevent"; | |
402 | dev->uevent_attr.attr.mode = S_IWUSR; | |
403 | if (dev->driver) | |
404 | dev->uevent_attr.attr.owner = dev->driver->owner; | |
405 | dev->uevent_attr.store = store_uevent; | |
406 | device_create_file(dev, &dev->uevent_attr); | |
407 | ||
23681e47 GKH |
408 | if (MAJOR(dev->devt)) { |
409 | struct device_attribute *attr; | |
410 | attr = kzalloc(sizeof(*attr), GFP_KERNEL); | |
411 | if (!attr) { | |
412 | error = -ENOMEM; | |
413 | goto PMError; | |
414 | } | |
415 | attr->attr.name = "dev"; | |
416 | attr->attr.mode = S_IRUGO; | |
417 | if (dev->driver) | |
418 | attr->attr.owner = dev->driver->owner; | |
419 | attr->show = show_dev; | |
420 | error = device_create_file(dev, attr); | |
421 | if (error) { | |
422 | kfree(attr); | |
423 | goto attrError; | |
424 | } | |
425 | ||
426 | dev->devt_attr = attr; | |
427 | } | |
428 | ||
b9d9c82b KS |
429 | if (dev->class) { |
430 | sysfs_create_link(&dev->kobj, &dev->class->subsys.kset.kobj, | |
431 | "subsystem"); | |
23681e47 GKH |
432 | sysfs_create_link(&dev->class->subsys.kset.kobj, &dev->kobj, |
433 | dev->bus_id); | |
64bb5d2c GKH |
434 | if (parent) { |
435 | sysfs_create_link(&dev->kobj, &dev->parent->kobj, "device"); | |
436 | class_name = make_class_name(dev->class->name, &dev->kobj); | |
437 | sysfs_create_link(&dev->parent->kobj, &dev->kobj, class_name); | |
438 | } | |
b9d9c82b | 439 | } |
23681e47 | 440 | |
2620efef GKH |
441 | if ((error = device_add_attrs(dev))) |
442 | goto AttrsError; | |
de0ff00d GKH |
443 | if ((error = device_add_groups(dev))) |
444 | goto GroupError; | |
1da177e4 LT |
445 | if ((error = device_pm_add(dev))) |
446 | goto PMError; | |
447 | if ((error = bus_add_device(dev))) | |
448 | goto BusError; | |
53877d06 KS |
449 | kobject_uevent(&dev->kobj, KOBJ_ADD); |
450 | bus_attach_device(dev); | |
1da177e4 | 451 | if (parent) |
d856f1e3 | 452 | klist_add_tail(&dev->knode_parent, &parent->klist_children); |
1da177e4 | 453 | |
5d9fd169 | 454 | if (dev->class) { |
5d9fd169 | 455 | down(&dev->class->sem); |
c47ed219 | 456 | /* tie the class to the device */ |
5d9fd169 | 457 | list_add_tail(&dev->node, &dev->class->devices); |
c47ed219 GKH |
458 | |
459 | /* notify any interfaces that the device is here */ | |
460 | list_for_each_entry(class_intf, &dev->class->interfaces, node) | |
461 | if (class_intf->add_dev) | |
462 | class_intf->add_dev(dev, class_intf); | |
5d9fd169 GKH |
463 | up(&dev->class->sem); |
464 | } | |
465 | ||
1da177e4 LT |
466 | /* notify platform of device entry */ |
467 | if (platform_notify) | |
468 | platform_notify(dev); | |
469 | Done: | |
e9a7d305 | 470 | kfree(class_name); |
1da177e4 LT |
471 | put_device(dev); |
472 | return error; | |
473 | BusError: | |
474 | device_pm_remove(dev); | |
475 | PMError: | |
de0ff00d GKH |
476 | device_remove_groups(dev); |
477 | GroupError: | |
2620efef GKH |
478 | device_remove_attrs(dev); |
479 | AttrsError: | |
23681e47 GKH |
480 | if (dev->devt_attr) { |
481 | device_remove_file(dev, dev->devt_attr); | |
482 | kfree(dev->devt_attr); | |
483 | } | |
484 | attrError: | |
312c004d | 485 | kobject_uevent(&dev->kobj, KOBJ_REMOVE); |
1da177e4 LT |
486 | kobject_del(&dev->kobj); |
487 | Error: | |
488 | if (parent) | |
489 | put_device(parent); | |
490 | goto Done; | |
491 | } | |
492 | ||
493 | ||
494 | /** | |
495 | * device_register - register a device with the system. | |
496 | * @dev: pointer to the device structure | |
497 | * | |
498 | * This happens in two clean steps - initialize the device | |
499 | * and add it to the system. The two steps can be called | |
500 | * separately, but this is the easiest and most common. | |
501 | * I.e. you should only call the two helpers separately if | |
502 | * have a clearly defined need to use and refcount the device | |
503 | * before it is added to the hierarchy. | |
504 | */ | |
505 | ||
506 | int device_register(struct device *dev) | |
507 | { | |
508 | device_initialize(dev); | |
509 | return device_add(dev); | |
510 | } | |
511 | ||
512 | ||
513 | /** | |
514 | * get_device - increment reference count for device. | |
515 | * @dev: device. | |
516 | * | |
517 | * This simply forwards the call to kobject_get(), though | |
518 | * we do take care to provide for the case that we get a NULL | |
519 | * pointer passed in. | |
520 | */ | |
521 | ||
522 | struct device * get_device(struct device * dev) | |
523 | { | |
524 | return dev ? to_dev(kobject_get(&dev->kobj)) : NULL; | |
525 | } | |
526 | ||
527 | ||
528 | /** | |
529 | * put_device - decrement reference count. | |
530 | * @dev: device in question. | |
531 | */ | |
532 | void put_device(struct device * dev) | |
533 | { | |
534 | if (dev) | |
535 | kobject_put(&dev->kobj); | |
536 | } | |
537 | ||
538 | ||
539 | /** | |
540 | * device_del - delete device from system. | |
541 | * @dev: device. | |
542 | * | |
543 | * This is the first part of the device unregistration | |
544 | * sequence. This removes the device from the lists we control | |
545 | * from here, has it removed from the other driver model | |
546 | * subsystems it was added to in device_add(), and removes it | |
547 | * from the kobject hierarchy. | |
548 | * | |
549 | * NOTE: this should be called manually _iff_ device_add() was | |
550 | * also called manually. | |
551 | */ | |
552 | ||
553 | void device_del(struct device * dev) | |
554 | { | |
555 | struct device * parent = dev->parent; | |
e9a7d305 | 556 | char *class_name = NULL; |
c47ed219 | 557 | struct class_interface *class_intf; |
1da177e4 | 558 | |
1da177e4 | 559 | if (parent) |
d62c0f9f | 560 | klist_del(&dev->knode_parent); |
23681e47 GKH |
561 | if (dev->devt_attr) |
562 | device_remove_file(dev, dev->devt_attr); | |
b9d9c82b KS |
563 | if (dev->class) { |
564 | sysfs_remove_link(&dev->kobj, "subsystem"); | |
23681e47 | 565 | sysfs_remove_link(&dev->class->subsys.kset.kobj, dev->bus_id); |
e9a7d305 | 566 | class_name = make_class_name(dev->class->name, &dev->kobj); |
64bb5d2c GKH |
567 | if (parent) { |
568 | sysfs_remove_link(&dev->kobj, "device"); | |
569 | sysfs_remove_link(&dev->parent->kobj, class_name); | |
570 | } | |
e9a7d305 | 571 | kfree(class_name); |
5d9fd169 | 572 | down(&dev->class->sem); |
c47ed219 GKH |
573 | /* notify any interfaces that the device is now gone */ |
574 | list_for_each_entry(class_intf, &dev->class->interfaces, node) | |
575 | if (class_intf->remove_dev) | |
576 | class_intf->remove_dev(dev, class_intf); | |
577 | /* remove the device from the class list */ | |
5d9fd169 GKH |
578 | list_del_init(&dev->node); |
579 | up(&dev->class->sem); | |
b9d9c82b | 580 | } |
a7fd6706 | 581 | device_remove_file(dev, &dev->uevent_attr); |
de0ff00d | 582 | device_remove_groups(dev); |
2620efef | 583 | device_remove_attrs(dev); |
1da177e4 LT |
584 | |
585 | /* Notify the platform of the removal, in case they | |
586 | * need to do anything... | |
587 | */ | |
588 | if (platform_notify_remove) | |
589 | platform_notify_remove(dev); | |
590 | bus_remove_device(dev); | |
591 | device_pm_remove(dev); | |
312c004d | 592 | kobject_uevent(&dev->kobj, KOBJ_REMOVE); |
1da177e4 LT |
593 | kobject_del(&dev->kobj); |
594 | if (parent) | |
595 | put_device(parent); | |
596 | } | |
597 | ||
598 | /** | |
599 | * device_unregister - unregister device from system. | |
600 | * @dev: device going away. | |
601 | * | |
602 | * We do this in two parts, like we do device_register(). First, | |
603 | * we remove it from all the subsystems with device_del(), then | |
604 | * we decrement the reference count via put_device(). If that | |
605 | * is the final reference count, the device will be cleaned up | |
606 | * via device_release() above. Otherwise, the structure will | |
607 | * stick around until the final reference to the device is dropped. | |
608 | */ | |
609 | void device_unregister(struct device * dev) | |
610 | { | |
611 | pr_debug("DEV: Unregistering device. ID = '%s'\n", dev->bus_id); | |
612 | device_del(dev); | |
613 | put_device(dev); | |
614 | } | |
615 | ||
616 | ||
36239577 PM |
617 | static struct device * next_device(struct klist_iter * i) |
618 | { | |
619 | struct klist_node * n = klist_next(i); | |
620 | return n ? container_of(n, struct device, knode_parent) : NULL; | |
621 | } | |
622 | ||
1da177e4 LT |
623 | /** |
624 | * device_for_each_child - device child iterator. | |
c41455fb | 625 | * @parent: parent struct device. |
1da177e4 LT |
626 | * @data: data for the callback. |
627 | * @fn: function to be called for each device. | |
628 | * | |
c41455fb | 629 | * Iterate over @parent's child devices, and call @fn for each, |
1da177e4 LT |
630 | * passing it @data. |
631 | * | |
632 | * We check the return of @fn each time. If it returns anything | |
633 | * other than 0, we break out and return that value. | |
634 | */ | |
36239577 | 635 | int device_for_each_child(struct device * parent, void * data, |
1da177e4 LT |
636 | int (*fn)(struct device *, void *)) |
637 | { | |
36239577 | 638 | struct klist_iter i; |
1da177e4 LT |
639 | struct device * child; |
640 | int error = 0; | |
641 | ||
36239577 PM |
642 | klist_iter_init(&parent->klist_children, &i); |
643 | while ((child = next_device(&i)) && !error) | |
644 | error = fn(child, data); | |
645 | klist_iter_exit(&i); | |
1da177e4 LT |
646 | return error; |
647 | } | |
648 | ||
1da177e4 LT |
649 | int __init devices_init(void) |
650 | { | |
651 | return subsystem_register(&devices_subsys); | |
652 | } | |
653 | ||
654 | EXPORT_SYMBOL_GPL(device_for_each_child); | |
655 | ||
656 | EXPORT_SYMBOL_GPL(device_initialize); | |
657 | EXPORT_SYMBOL_GPL(device_add); | |
658 | EXPORT_SYMBOL_GPL(device_register); | |
659 | ||
660 | EXPORT_SYMBOL_GPL(device_del); | |
661 | EXPORT_SYMBOL_GPL(device_unregister); | |
662 | EXPORT_SYMBOL_GPL(get_device); | |
663 | EXPORT_SYMBOL_GPL(put_device); | |
1da177e4 LT |
664 | |
665 | EXPORT_SYMBOL_GPL(device_create_file); | |
666 | EXPORT_SYMBOL_GPL(device_remove_file); | |
23681e47 GKH |
667 | |
668 | ||
669 | static void device_create_release(struct device *dev) | |
670 | { | |
671 | pr_debug("%s called for %s\n", __FUNCTION__, dev->bus_id); | |
672 | kfree(dev); | |
673 | } | |
674 | ||
675 | /** | |
676 | * device_create - creates a device and registers it with sysfs | |
42734daf HK |
677 | * @class: pointer to the struct class that this device should be registered to |
678 | * @parent: pointer to the parent struct device of this new device, if any | |
679 | * @devt: the dev_t for the char device to be added | |
680 | * @fmt: string for the device's name | |
681 | * | |
682 | * This function can be used by char device classes. A struct device | |
683 | * will be created in sysfs, registered to the specified class. | |
23681e47 | 684 | * |
23681e47 GKH |
685 | * A "dev" file will be created, showing the dev_t for the device, if |
686 | * the dev_t is not 0,0. | |
42734daf HK |
687 | * If a pointer to a parent struct device is passed in, the newly created |
688 | * struct device will be a child of that device in sysfs. | |
689 | * The pointer to the struct device will be returned from the call. | |
690 | * Any further sysfs files that might be required can be created using this | |
23681e47 GKH |
691 | * pointer. |
692 | * | |
693 | * Note: the struct class passed to this function must have previously | |
694 | * been created with a call to class_create(). | |
695 | */ | |
696 | struct device *device_create(struct class *class, struct device *parent, | |
5cbe5f8a | 697 | dev_t devt, const char *fmt, ...) |
23681e47 GKH |
698 | { |
699 | va_list args; | |
700 | struct device *dev = NULL; | |
701 | int retval = -ENODEV; | |
702 | ||
703 | if (class == NULL || IS_ERR(class)) | |
704 | goto error; | |
23681e47 GKH |
705 | |
706 | dev = kzalloc(sizeof(*dev), GFP_KERNEL); | |
707 | if (!dev) { | |
708 | retval = -ENOMEM; | |
709 | goto error; | |
710 | } | |
711 | ||
712 | dev->devt = devt; | |
713 | dev->class = class; | |
714 | dev->parent = parent; | |
715 | dev->release = device_create_release; | |
716 | ||
717 | va_start(args, fmt); | |
718 | vsnprintf(dev->bus_id, BUS_ID_SIZE, fmt, args); | |
719 | va_end(args); | |
720 | retval = device_register(dev); | |
721 | if (retval) | |
722 | goto error; | |
723 | ||
23681e47 GKH |
724 | return dev; |
725 | ||
726 | error: | |
727 | kfree(dev); | |
728 | return ERR_PTR(retval); | |
729 | } | |
730 | EXPORT_SYMBOL_GPL(device_create); | |
731 | ||
732 | /** | |
733 | * device_destroy - removes a device that was created with device_create() | |
42734daf HK |
734 | * @class: pointer to the struct class that this device was registered with |
735 | * @devt: the dev_t of the device that was previously registered | |
23681e47 | 736 | * |
42734daf HK |
737 | * This call unregisters and cleans up a device that was created with a |
738 | * call to device_create(). | |
23681e47 GKH |
739 | */ |
740 | void device_destroy(struct class *class, dev_t devt) | |
741 | { | |
742 | struct device *dev = NULL; | |
743 | struct device *dev_tmp; | |
744 | ||
745 | down(&class->sem); | |
746 | list_for_each_entry(dev_tmp, &class->devices, node) { | |
747 | if (dev_tmp->devt == devt) { | |
748 | dev = dev_tmp; | |
749 | break; | |
750 | } | |
751 | } | |
752 | up(&class->sem); | |
753 | ||
5d9fd169 | 754 | if (dev) |
23681e47 | 755 | device_unregister(dev); |
23681e47 GKH |
756 | } |
757 | EXPORT_SYMBOL_GPL(device_destroy); | |
a2de48ca GKH |
758 | |
759 | /** | |
760 | * device_rename - renames a device | |
761 | * @dev: the pointer to the struct device to be renamed | |
762 | * @new_name: the new name of the device | |
763 | */ | |
764 | int device_rename(struct device *dev, char *new_name) | |
765 | { | |
766 | char *old_class_name = NULL; | |
767 | char *new_class_name = NULL; | |
768 | char *old_symlink_name = NULL; | |
769 | int error; | |
770 | ||
771 | dev = get_device(dev); | |
772 | if (!dev) | |
773 | return -EINVAL; | |
774 | ||
775 | pr_debug("DEVICE: renaming '%s' to '%s'\n", dev->bus_id, new_name); | |
776 | ||
777 | if ((dev->class) && (dev->parent)) | |
778 | old_class_name = make_class_name(dev->class->name, &dev->kobj); | |
779 | ||
780 | if (dev->class) { | |
781 | old_symlink_name = kmalloc(BUS_ID_SIZE, GFP_KERNEL); | |
782 | if (!old_symlink_name) | |
783 | return -ENOMEM; | |
784 | strlcpy(old_symlink_name, dev->bus_id, BUS_ID_SIZE); | |
785 | } | |
786 | ||
787 | strlcpy(dev->bus_id, new_name, BUS_ID_SIZE); | |
788 | ||
789 | error = kobject_rename(&dev->kobj, new_name); | |
790 | ||
791 | if (old_class_name) { | |
792 | new_class_name = make_class_name(dev->class->name, &dev->kobj); | |
793 | if (new_class_name) { | |
794 | sysfs_create_link(&dev->parent->kobj, &dev->kobj, | |
795 | new_class_name); | |
796 | sysfs_remove_link(&dev->parent->kobj, old_class_name); | |
797 | } | |
798 | } | |
799 | if (dev->class) { | |
800 | sysfs_remove_link(&dev->class->subsys.kset.kobj, | |
801 | old_symlink_name); | |
802 | sysfs_create_link(&dev->class->subsys.kset.kobj, &dev->kobj, | |
803 | dev->bus_id); | |
804 | } | |
805 | put_device(dev); | |
806 | ||
807 | kfree(old_class_name); | |
808 | kfree(new_class_name); | |
809 | kfree(old_symlink_name); | |
810 | ||
811 | return error; | |
812 | } |