Commit | Line | Data |
---|---|---|
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> |
116af378 | 20 | #include <linux/notifier.h> |
1da177e4 LT |
21 | |
22 | #include <asm/semaphore.h> | |
23 | ||
24 | #include "base.h" | |
25 | #include "power/power.h" | |
26 | ||
27 | int (*platform_notify)(struct device * dev) = NULL; | |
28 | int (*platform_notify_remove)(struct device * dev) = NULL; | |
29 | ||
30 | /* | |
31 | * sysfs bindings for devices. | |
32 | */ | |
33 | ||
3e95637a AS |
34 | /** |
35 | * dev_driver_string - Return a device's driver name, if at all possible | |
36 | * @dev: struct device to get the name of | |
37 | * | |
38 | * Will return the device's driver's name if it is bound to a device. If | |
39 | * the device is not bound to a device, it will return the name of the bus | |
40 | * it is attached to. If it is not attached to a bus either, an empty | |
41 | * string will be returned. | |
42 | */ | |
43 | const char *dev_driver_string(struct device *dev) | |
44 | { | |
45 | return dev->driver ? dev->driver->name : | |
46 | (dev->bus ? dev->bus->name : ""); | |
47 | } | |
310a922d | 48 | EXPORT_SYMBOL(dev_driver_string); |
3e95637a | 49 | |
1da177e4 LT |
50 | #define to_dev(obj) container_of(obj, struct device, kobj) |
51 | #define to_dev_attr(_attr) container_of(_attr, struct device_attribute, attr) | |
52 | ||
1da177e4 LT |
53 | static ssize_t |
54 | dev_attr_show(struct kobject * kobj, struct attribute * attr, char * buf) | |
55 | { | |
56 | struct device_attribute * dev_attr = to_dev_attr(attr); | |
57 | struct device * dev = to_dev(kobj); | |
4a0c20bf | 58 | ssize_t ret = -EIO; |
1da177e4 LT |
59 | |
60 | if (dev_attr->show) | |
54b6f35c | 61 | ret = dev_attr->show(dev, dev_attr, buf); |
1da177e4 LT |
62 | return ret; |
63 | } | |
64 | ||
65 | static ssize_t | |
66 | dev_attr_store(struct kobject * kobj, struct attribute * attr, | |
67 | const char * buf, size_t count) | |
68 | { | |
69 | struct device_attribute * dev_attr = to_dev_attr(attr); | |
70 | struct device * dev = to_dev(kobj); | |
4a0c20bf | 71 | ssize_t ret = -EIO; |
1da177e4 LT |
72 | |
73 | if (dev_attr->store) | |
54b6f35c | 74 | ret = dev_attr->store(dev, dev_attr, buf, count); |
1da177e4 LT |
75 | return ret; |
76 | } | |
77 | ||
78 | static struct sysfs_ops dev_sysfs_ops = { | |
79 | .show = dev_attr_show, | |
80 | .store = dev_attr_store, | |
81 | }; | |
82 | ||
83 | ||
84 | /** | |
85 | * device_release - free device structure. | |
86 | * @kobj: device's kobject. | |
87 | * | |
88 | * This is called once the reference count for the object | |
89 | * reaches 0. We forward the call to the device's release | |
90 | * method, which should handle actually freeing the structure. | |
91 | */ | |
92 | static void device_release(struct kobject * kobj) | |
93 | { | |
94 | struct device * dev = to_dev(kobj); | |
95 | ||
96 | if (dev->release) | |
97 | dev->release(dev); | |
2620efef GKH |
98 | else if (dev->class && dev->class->dev_release) |
99 | dev->class->dev_release(dev); | |
1da177e4 LT |
100 | else { |
101 | printk(KERN_ERR "Device '%s' does not have a release() function, " | |
102 | "it is broken and must be fixed.\n", | |
103 | dev->bus_id); | |
104 | WARN_ON(1); | |
105 | } | |
106 | } | |
107 | ||
108 | static struct kobj_type ktype_device = { | |
109 | .release = device_release, | |
110 | .sysfs_ops = &dev_sysfs_ops, | |
1da177e4 LT |
111 | }; |
112 | ||
113 | ||
312c004d | 114 | static int dev_uevent_filter(struct kset *kset, struct kobject *kobj) |
1da177e4 LT |
115 | { |
116 | struct kobj_type *ktype = get_ktype(kobj); | |
117 | ||
118 | if (ktype == &ktype_device) { | |
119 | struct device *dev = to_dev(kobj); | |
120 | if (dev->bus) | |
121 | return 1; | |
23681e47 GKH |
122 | if (dev->class) |
123 | return 1; | |
1da177e4 LT |
124 | } |
125 | return 0; | |
126 | } | |
127 | ||
312c004d | 128 | static const char *dev_uevent_name(struct kset *kset, struct kobject *kobj) |
1da177e4 LT |
129 | { |
130 | struct device *dev = to_dev(kobj); | |
131 | ||
23681e47 GKH |
132 | if (dev->bus) |
133 | return dev->bus->name; | |
134 | if (dev->class) | |
135 | return dev->class->name; | |
136 | return NULL; | |
1da177e4 LT |
137 | } |
138 | ||
312c004d | 139 | static int dev_uevent(struct kset *kset, struct kobject *kobj, char **envp, |
1da177e4 LT |
140 | int num_envp, char *buffer, int buffer_size) |
141 | { | |
142 | struct device *dev = to_dev(kobj); | |
143 | int i = 0; | |
144 | int length = 0; | |
145 | int retval = 0; | |
146 | ||
23681e47 GKH |
147 | /* add the major/minor if present */ |
148 | if (MAJOR(dev->devt)) { | |
149 | add_uevent_var(envp, num_envp, &i, | |
150 | buffer, buffer_size, &length, | |
151 | "MAJOR=%u", MAJOR(dev->devt)); | |
152 | add_uevent_var(envp, num_envp, &i, | |
153 | buffer, buffer_size, &length, | |
154 | "MINOR=%u", MINOR(dev->devt)); | |
155 | } | |
156 | ||
d81d9d6b | 157 | /* add bus name (same as SUBSYSTEM, deprecated) */ |
1da177e4 | 158 | if (dev->bus) |
312c004d KS |
159 | add_uevent_var(envp, num_envp, &i, |
160 | buffer, buffer_size, &length, | |
161 | "PHYSDEVBUS=%s", dev->bus->name); | |
1da177e4 | 162 | |
d81d9d6b KS |
163 | /* add driver name (PHYSDEV* values are deprecated)*/ |
164 | if (dev->driver) { | |
165 | add_uevent_var(envp, num_envp, &i, | |
166 | buffer, buffer_size, &length, | |
167 | "DRIVER=%s", dev->driver->name); | |
312c004d KS |
168 | add_uevent_var(envp, num_envp, &i, |
169 | buffer, buffer_size, &length, | |
170 | "PHYSDEVDRIVER=%s", dev->driver->name); | |
d81d9d6b | 171 | } |
1da177e4 LT |
172 | |
173 | /* terminate, set to next free slot, shrink available space */ | |
174 | envp[i] = NULL; | |
175 | envp = &envp[i]; | |
176 | num_envp -= i; | |
177 | buffer = &buffer[length]; | |
178 | buffer_size -= length; | |
179 | ||
312c004d | 180 | if (dev->bus && dev->bus->uevent) { |
1da177e4 | 181 | /* have the bus specific function add its stuff */ |
312c004d | 182 | retval = dev->bus->uevent(dev, envp, num_envp, buffer, buffer_size); |
1da177e4 | 183 | if (retval) { |
312c004d | 184 | pr_debug ("%s - uevent() returned %d\n", |
1da177e4 LT |
185 | __FUNCTION__, retval); |
186 | } | |
187 | } | |
188 | ||
2620efef GKH |
189 | if (dev->class && dev->class->dev_uevent) { |
190 | /* have the class specific function add its stuff */ | |
191 | retval = dev->class->dev_uevent(dev, envp, num_envp, buffer, buffer_size); | |
192 | if (retval) { | |
193 | pr_debug("%s - dev_uevent() returned %d\n", | |
194 | __FUNCTION__, retval); | |
195 | } | |
196 | } | |
197 | ||
1da177e4 LT |
198 | return retval; |
199 | } | |
200 | ||
312c004d KS |
201 | static struct kset_uevent_ops device_uevent_ops = { |
202 | .filter = dev_uevent_filter, | |
203 | .name = dev_uevent_name, | |
204 | .uevent = dev_uevent, | |
1da177e4 LT |
205 | }; |
206 | ||
a7fd6706 KS |
207 | static ssize_t store_uevent(struct device *dev, struct device_attribute *attr, |
208 | const char *buf, size_t count) | |
209 | { | |
312c004d | 210 | kobject_uevent(&dev->kobj, KOBJ_ADD); |
a7fd6706 KS |
211 | return count; |
212 | } | |
213 | ||
de0ff00d GKH |
214 | static int device_add_groups(struct device *dev) |
215 | { | |
216 | int i; | |
217 | int error = 0; | |
218 | ||
219 | if (dev->groups) { | |
220 | for (i = 0; dev->groups[i]; i++) { | |
221 | error = sysfs_create_group(&dev->kobj, dev->groups[i]); | |
222 | if (error) { | |
223 | while (--i >= 0) | |
224 | sysfs_remove_group(&dev->kobj, dev->groups[i]); | |
225 | goto out; | |
226 | } | |
227 | } | |
228 | } | |
229 | out: | |
230 | return error; | |
231 | } | |
232 | ||
233 | static void device_remove_groups(struct device *dev) | |
234 | { | |
235 | int i; | |
236 | if (dev->groups) { | |
237 | for (i = 0; dev->groups[i]; i++) { | |
238 | sysfs_remove_group(&dev->kobj, dev->groups[i]); | |
239 | } | |
240 | } | |
241 | } | |
242 | ||
2620efef GKH |
243 | static int device_add_attrs(struct device *dev) |
244 | { | |
245 | struct class *class = dev->class; | |
246 | int error = 0; | |
247 | int i; | |
248 | ||
249 | if (!class) | |
250 | return 0; | |
251 | ||
252 | if (class->dev_attrs) { | |
253 | for (i = 0; attr_name(class->dev_attrs[i]); i++) { | |
254 | error = device_create_file(dev, &class->dev_attrs[i]); | |
255 | if (error) | |
256 | break; | |
257 | } | |
258 | } | |
259 | if (error) | |
260 | while (--i >= 0) | |
261 | device_remove_file(dev, &class->dev_attrs[i]); | |
262 | return error; | |
263 | } | |
264 | ||
265 | static void device_remove_attrs(struct device *dev) | |
266 | { | |
267 | struct class *class = dev->class; | |
268 | int i; | |
269 | ||
270 | if (!class) | |
271 | return; | |
272 | ||
273 | if (class->dev_attrs) { | |
274 | for (i = 0; attr_name(class->dev_attrs[i]); i++) | |
275 | device_remove_file(dev, &class->dev_attrs[i]); | |
276 | } | |
277 | } | |
278 | ||
279 | ||
23681e47 GKH |
280 | static ssize_t show_dev(struct device *dev, struct device_attribute *attr, |
281 | char *buf) | |
282 | { | |
283 | return print_dev_t(buf, dev->devt); | |
284 | } | |
285 | ||
0863afb3 MW |
286 | /* |
287 | * devices_subsys - structure to be registered with kobject core. | |
1da177e4 LT |
288 | */ |
289 | ||
312c004d | 290 | decl_subsys(devices, &ktype_device, &device_uevent_ops); |
1da177e4 LT |
291 | |
292 | ||
293 | /** | |
294 | * device_create_file - create sysfs attribute file for device. | |
295 | * @dev: device. | |
296 | * @attr: device attribute descriptor. | |
297 | */ | |
298 | ||
299 | int device_create_file(struct device * dev, struct device_attribute * attr) | |
300 | { | |
301 | int error = 0; | |
302 | if (get_device(dev)) { | |
303 | error = sysfs_create_file(&dev->kobj, &attr->attr); | |
304 | put_device(dev); | |
305 | } | |
306 | return error; | |
307 | } | |
308 | ||
309 | /** | |
310 | * device_remove_file - remove sysfs attribute file. | |
311 | * @dev: device. | |
312 | * @attr: device attribute descriptor. | |
313 | */ | |
314 | ||
315 | void device_remove_file(struct device * dev, struct device_attribute * attr) | |
316 | { | |
317 | if (get_device(dev)) { | |
318 | sysfs_remove_file(&dev->kobj, &attr->attr); | |
319 | put_device(dev); | |
320 | } | |
321 | } | |
322 | ||
2589f188 GKH |
323 | /** |
324 | * device_create_bin_file - create sysfs binary attribute file for device. | |
325 | * @dev: device. | |
326 | * @attr: device binary attribute descriptor. | |
327 | */ | |
328 | int device_create_bin_file(struct device *dev, struct bin_attribute *attr) | |
329 | { | |
330 | int error = -EINVAL; | |
331 | if (dev) | |
332 | error = sysfs_create_bin_file(&dev->kobj, attr); | |
333 | return error; | |
334 | } | |
335 | EXPORT_SYMBOL_GPL(device_create_bin_file); | |
336 | ||
337 | /** | |
338 | * device_remove_bin_file - remove sysfs binary attribute file | |
339 | * @dev: device. | |
340 | * @attr: device binary attribute descriptor. | |
341 | */ | |
342 | void device_remove_bin_file(struct device *dev, struct bin_attribute *attr) | |
343 | { | |
344 | if (dev) | |
345 | sysfs_remove_bin_file(&dev->kobj, attr); | |
346 | } | |
347 | EXPORT_SYMBOL_GPL(device_remove_bin_file); | |
348 | ||
34bb61f9 JB |
349 | static void klist_children_get(struct klist_node *n) |
350 | { | |
351 | struct device *dev = container_of(n, struct device, knode_parent); | |
352 | ||
353 | get_device(dev); | |
354 | } | |
355 | ||
356 | static void klist_children_put(struct klist_node *n) | |
357 | { | |
358 | struct device *dev = container_of(n, struct device, knode_parent); | |
359 | ||
360 | put_device(dev); | |
361 | } | |
362 | ||
1da177e4 LT |
363 | |
364 | /** | |
365 | * device_initialize - init device structure. | |
366 | * @dev: device. | |
367 | * | |
368 | * This prepares the device for use by other layers, | |
369 | * including adding it to the device hierarchy. | |
370 | * It is the first half of device_register(), if called by | |
371 | * that, though it can also be called separately, so one | |
372 | * may use @dev's fields (e.g. the refcount). | |
373 | */ | |
374 | ||
375 | void device_initialize(struct device *dev) | |
376 | { | |
377 | kobj_set_kset_s(dev, devices_subsys); | |
378 | kobject_init(&dev->kobj); | |
34bb61f9 JB |
379 | klist_init(&dev->klist_children, klist_children_get, |
380 | klist_children_put); | |
1da177e4 | 381 | INIT_LIST_HEAD(&dev->dma_pools); |
23681e47 | 382 | INIT_LIST_HEAD(&dev->node); |
af70316a | 383 | init_MUTEX(&dev->sem); |
0ac85241 | 384 | device_init_wakeup(dev, 0); |
1da177e4 LT |
385 | } |
386 | ||
f0ee61a6 GKH |
387 | static int virtual_device_parent(struct device *dev) |
388 | { | |
389 | if (!dev->class) | |
390 | return -ENODEV; | |
391 | ||
392 | if (!dev->class->virtual_dir) { | |
393 | static struct kobject *virtual_dir = NULL; | |
394 | ||
395 | if (!virtual_dir) | |
396 | virtual_dir = kobject_add_dir(&devices_subsys.kset.kobj, "virtual"); | |
397 | dev->class->virtual_dir = kobject_add_dir(virtual_dir, dev->class->name); | |
398 | } | |
399 | ||
400 | dev->kobj.parent = dev->class->virtual_dir; | |
401 | return 0; | |
402 | } | |
403 | ||
1da177e4 LT |
404 | /** |
405 | * device_add - add device to device hierarchy. | |
406 | * @dev: device. | |
407 | * | |
408 | * This is part 2 of device_register(), though may be called | |
409 | * separately _iff_ device_initialize() has been called separately. | |
410 | * | |
411 | * This adds it to the kobject hierarchy via kobject_add(), adds it | |
412 | * to the global and sibling lists for the device, then | |
413 | * adds it to the other relevant subsystems of the driver model. | |
414 | */ | |
415 | int device_add(struct device *dev) | |
416 | { | |
417 | struct device *parent = NULL; | |
e9a7d305 | 418 | char *class_name = NULL; |
c47ed219 | 419 | struct class_interface *class_intf; |
1da177e4 LT |
420 | int error = -EINVAL; |
421 | ||
422 | dev = get_device(dev); | |
423 | if (!dev || !strlen(dev->bus_id)) | |
424 | goto Error; | |
425 | ||
c205ef48 GKH |
426 | /* if this is a class device, and has no parent, create one */ |
427 | if ((dev->class) && (dev->parent == NULL)) { | |
428 | error = virtual_device_parent(dev); | |
429 | if (error) | |
430 | goto Error; | |
431 | } | |
432 | ||
1da177e4 LT |
433 | parent = get_device(dev->parent); |
434 | ||
435 | pr_debug("DEV: registering device: ID = '%s'\n", dev->bus_id); | |
436 | ||
437 | /* first, register with generic layer. */ | |
438 | kobject_set_name(&dev->kobj, "%s", dev->bus_id); | |
439 | if (parent) | |
440 | dev->kobj.parent = &parent->kobj; | |
441 | ||
442 | if ((error = kobject_add(&dev->kobj))) | |
443 | goto Error; | |
a7fd6706 | 444 | |
37022644 BW |
445 | /* notify platform of device entry */ |
446 | if (platform_notify) | |
447 | platform_notify(dev); | |
448 | ||
116af378 BH |
449 | /* notify clients of device entry (new way) */ |
450 | if (dev->bus) | |
451 | blocking_notifier_call_chain(&dev->bus->bus_notifier, | |
452 | BUS_NOTIFY_ADD_DEVICE, dev); | |
453 | ||
a7fd6706 KS |
454 | dev->uevent_attr.attr.name = "uevent"; |
455 | dev->uevent_attr.attr.mode = S_IWUSR; | |
456 | if (dev->driver) | |
457 | dev->uevent_attr.attr.owner = dev->driver->owner; | |
458 | dev->uevent_attr.store = store_uevent; | |
a306eea4 CH |
459 | error = device_create_file(dev, &dev->uevent_attr); |
460 | if (error) | |
461 | goto attrError; | |
a7fd6706 | 462 | |
23681e47 GKH |
463 | if (MAJOR(dev->devt)) { |
464 | struct device_attribute *attr; | |
465 | attr = kzalloc(sizeof(*attr), GFP_KERNEL); | |
466 | if (!attr) { | |
467 | error = -ENOMEM; | |
a306eea4 | 468 | goto ueventattrError; |
23681e47 GKH |
469 | } |
470 | attr->attr.name = "dev"; | |
471 | attr->attr.mode = S_IRUGO; | |
472 | if (dev->driver) | |
473 | attr->attr.owner = dev->driver->owner; | |
474 | attr->show = show_dev; | |
475 | error = device_create_file(dev, attr); | |
476 | if (error) { | |
477 | kfree(attr); | |
a306eea4 | 478 | goto ueventattrError; |
23681e47 GKH |
479 | } |
480 | ||
481 | dev->devt_attr = attr; | |
482 | } | |
483 | ||
b9d9c82b KS |
484 | if (dev->class) { |
485 | sysfs_create_link(&dev->kobj, &dev->class->subsys.kset.kobj, | |
486 | "subsystem"); | |
23681e47 GKH |
487 | sysfs_create_link(&dev->class->subsys.kset.kobj, &dev->kobj, |
488 | dev->bus_id); | |
64bb5d2c GKH |
489 | if (parent) { |
490 | sysfs_create_link(&dev->kobj, &dev->parent->kobj, "device"); | |
491 | class_name = make_class_name(dev->class->name, &dev->kobj); | |
492 | sysfs_create_link(&dev->parent->kobj, &dev->kobj, class_name); | |
493 | } | |
b9d9c82b | 494 | } |
23681e47 | 495 | |
2620efef GKH |
496 | if ((error = device_add_attrs(dev))) |
497 | goto AttrsError; | |
de0ff00d GKH |
498 | if ((error = device_add_groups(dev))) |
499 | goto GroupError; | |
1da177e4 LT |
500 | if ((error = device_pm_add(dev))) |
501 | goto PMError; | |
502 | if ((error = bus_add_device(dev))) | |
503 | goto BusError; | |
53877d06 | 504 | kobject_uevent(&dev->kobj, KOBJ_ADD); |
f70fa629 AS |
505 | if ((error = bus_attach_device(dev))) |
506 | goto AttachError; | |
1da177e4 | 507 | if (parent) |
d856f1e3 | 508 | klist_add_tail(&dev->knode_parent, &parent->klist_children); |
1da177e4 | 509 | |
5d9fd169 | 510 | if (dev->class) { |
5d9fd169 | 511 | down(&dev->class->sem); |
c47ed219 | 512 | /* tie the class to the device */ |
5d9fd169 | 513 | list_add_tail(&dev->node, &dev->class->devices); |
c47ed219 GKH |
514 | |
515 | /* notify any interfaces that the device is here */ | |
516 | list_for_each_entry(class_intf, &dev->class->interfaces, node) | |
517 | if (class_intf->add_dev) | |
518 | class_intf->add_dev(dev, class_intf); | |
5d9fd169 GKH |
519 | up(&dev->class->sem); |
520 | } | |
1da177e4 | 521 | Done: |
e9a7d305 | 522 | kfree(class_name); |
1da177e4 LT |
523 | put_device(dev); |
524 | return error; | |
f70fa629 AS |
525 | AttachError: |
526 | bus_remove_device(dev); | |
1da177e4 LT |
527 | BusError: |
528 | device_pm_remove(dev); | |
529 | PMError: | |
116af378 BH |
530 | if (dev->bus) |
531 | blocking_notifier_call_chain(&dev->bus->bus_notifier, | |
532 | BUS_NOTIFY_DEL_DEVICE, dev); | |
de0ff00d GKH |
533 | device_remove_groups(dev); |
534 | GroupError: | |
2620efef GKH |
535 | device_remove_attrs(dev); |
536 | AttrsError: | |
23681e47 GKH |
537 | if (dev->devt_attr) { |
538 | device_remove_file(dev, dev->devt_attr); | |
539 | kfree(dev->devt_attr); | |
540 | } | |
a306eea4 CH |
541 | ueventattrError: |
542 | device_remove_file(dev, &dev->uevent_attr); | |
23681e47 | 543 | attrError: |
312c004d | 544 | kobject_uevent(&dev->kobj, KOBJ_REMOVE); |
1da177e4 LT |
545 | kobject_del(&dev->kobj); |
546 | Error: | |
547 | if (parent) | |
548 | put_device(parent); | |
549 | goto Done; | |
550 | } | |
551 | ||
552 | ||
553 | /** | |
554 | * device_register - register a device with the system. | |
555 | * @dev: pointer to the device structure | |
556 | * | |
557 | * This happens in two clean steps - initialize the device | |
558 | * and add it to the system. The two steps can be called | |
559 | * separately, but this is the easiest and most common. | |
560 | * I.e. you should only call the two helpers separately if | |
561 | * have a clearly defined need to use and refcount the device | |
562 | * before it is added to the hierarchy. | |
563 | */ | |
564 | ||
565 | int device_register(struct device *dev) | |
566 | { | |
567 | device_initialize(dev); | |
568 | return device_add(dev); | |
569 | } | |
570 | ||
571 | ||
572 | /** | |
573 | * get_device - increment reference count for device. | |
574 | * @dev: device. | |
575 | * | |
576 | * This simply forwards the call to kobject_get(), though | |
577 | * we do take care to provide for the case that we get a NULL | |
578 | * pointer passed in. | |
579 | */ | |
580 | ||
581 | struct device * get_device(struct device * dev) | |
582 | { | |
583 | return dev ? to_dev(kobject_get(&dev->kobj)) : NULL; | |
584 | } | |
585 | ||
586 | ||
587 | /** | |
588 | * put_device - decrement reference count. | |
589 | * @dev: device in question. | |
590 | */ | |
591 | void put_device(struct device * dev) | |
592 | { | |
593 | if (dev) | |
594 | kobject_put(&dev->kobj); | |
595 | } | |
596 | ||
597 | ||
598 | /** | |
599 | * device_del - delete device from system. | |
600 | * @dev: device. | |
601 | * | |
602 | * This is the first part of the device unregistration | |
603 | * sequence. This removes the device from the lists we control | |
604 | * from here, has it removed from the other driver model | |
605 | * subsystems it was added to in device_add(), and removes it | |
606 | * from the kobject hierarchy. | |
607 | * | |
608 | * NOTE: this should be called manually _iff_ device_add() was | |
609 | * also called manually. | |
610 | */ | |
611 | ||
612 | void device_del(struct device * dev) | |
613 | { | |
614 | struct device * parent = dev->parent; | |
e9a7d305 | 615 | char *class_name = NULL; |
c47ed219 | 616 | struct class_interface *class_intf; |
1da177e4 | 617 | |
1da177e4 | 618 | if (parent) |
d62c0f9f | 619 | klist_del(&dev->knode_parent); |
82189b98 | 620 | if (dev->devt_attr) { |
23681e47 | 621 | device_remove_file(dev, dev->devt_attr); |
82189b98 CM |
622 | kfree(dev->devt_attr); |
623 | } | |
b9d9c82b KS |
624 | if (dev->class) { |
625 | sysfs_remove_link(&dev->kobj, "subsystem"); | |
23681e47 | 626 | sysfs_remove_link(&dev->class->subsys.kset.kobj, dev->bus_id); |
e9a7d305 | 627 | class_name = make_class_name(dev->class->name, &dev->kobj); |
64bb5d2c GKH |
628 | if (parent) { |
629 | sysfs_remove_link(&dev->kobj, "device"); | |
630 | sysfs_remove_link(&dev->parent->kobj, class_name); | |
631 | } | |
e9a7d305 | 632 | kfree(class_name); |
5d9fd169 | 633 | down(&dev->class->sem); |
c47ed219 GKH |
634 | /* notify any interfaces that the device is now gone */ |
635 | list_for_each_entry(class_intf, &dev->class->interfaces, node) | |
636 | if (class_intf->remove_dev) | |
637 | class_intf->remove_dev(dev, class_intf); | |
638 | /* remove the device from the class list */ | |
5d9fd169 GKH |
639 | list_del_init(&dev->node); |
640 | up(&dev->class->sem); | |
b9d9c82b | 641 | } |
a7fd6706 | 642 | device_remove_file(dev, &dev->uevent_attr); |
de0ff00d | 643 | device_remove_groups(dev); |
2620efef | 644 | device_remove_attrs(dev); |
1da177e4 LT |
645 | |
646 | /* Notify the platform of the removal, in case they | |
647 | * need to do anything... | |
648 | */ | |
649 | if (platform_notify_remove) | |
650 | platform_notify_remove(dev); | |
116af378 BH |
651 | if (dev->bus) |
652 | blocking_notifier_call_chain(&dev->bus->bus_notifier, | |
653 | BUS_NOTIFY_DEL_DEVICE, dev); | |
1da177e4 LT |
654 | bus_remove_device(dev); |
655 | device_pm_remove(dev); | |
312c004d | 656 | kobject_uevent(&dev->kobj, KOBJ_REMOVE); |
1da177e4 LT |
657 | kobject_del(&dev->kobj); |
658 | if (parent) | |
659 | put_device(parent); | |
660 | } | |
661 | ||
662 | /** | |
663 | * device_unregister - unregister device from system. | |
664 | * @dev: device going away. | |
665 | * | |
666 | * We do this in two parts, like we do device_register(). First, | |
667 | * we remove it from all the subsystems with device_del(), then | |
668 | * we decrement the reference count via put_device(). If that | |
669 | * is the final reference count, the device will be cleaned up | |
670 | * via device_release() above. Otherwise, the structure will | |
671 | * stick around until the final reference to the device is dropped. | |
672 | */ | |
673 | void device_unregister(struct device * dev) | |
674 | { | |
675 | pr_debug("DEV: Unregistering device. ID = '%s'\n", dev->bus_id); | |
676 | device_del(dev); | |
677 | put_device(dev); | |
678 | } | |
679 | ||
680 | ||
36239577 | 681 | static struct device * next_device(struct klist_iter * i) |
682 | { | |
683 | struct klist_node * n = klist_next(i); | |
684 | return n ? container_of(n, struct device, knode_parent) : NULL; | |
685 | } | |
686 | ||
1da177e4 LT |
687 | /** |
688 | * device_for_each_child - device child iterator. | |
c41455fb | 689 | * @parent: parent struct device. |
1da177e4 LT |
690 | * @data: data for the callback. |
691 | * @fn: function to be called for each device. | |
692 | * | |
c41455fb | 693 | * Iterate over @parent's child devices, and call @fn for each, |
1da177e4 LT |
694 | * passing it @data. |
695 | * | |
696 | * We check the return of @fn each time. If it returns anything | |
697 | * other than 0, we break out and return that value. | |
698 | */ | |
36239577 | 699 | int device_for_each_child(struct device * parent, void * data, |
1da177e4 LT |
700 | int (*fn)(struct device *, void *)) |
701 | { | |
36239577 | 702 | struct klist_iter i; |
1da177e4 LT |
703 | struct device * child; |
704 | int error = 0; | |
705 | ||
36239577 | 706 | klist_iter_init(&parent->klist_children, &i); |
707 | while ((child = next_device(&i)) && !error) | |
708 | error = fn(child, data); | |
709 | klist_iter_exit(&i); | |
1da177e4 LT |
710 | return error; |
711 | } | |
712 | ||
1da177e4 LT |
713 | int __init devices_init(void) |
714 | { | |
715 | return subsystem_register(&devices_subsys); | |
716 | } | |
717 | ||
718 | EXPORT_SYMBOL_GPL(device_for_each_child); | |
719 | ||
720 | EXPORT_SYMBOL_GPL(device_initialize); | |
721 | EXPORT_SYMBOL_GPL(device_add); | |
722 | EXPORT_SYMBOL_GPL(device_register); | |
723 | ||
724 | EXPORT_SYMBOL_GPL(device_del); | |
725 | EXPORT_SYMBOL_GPL(device_unregister); | |
726 | EXPORT_SYMBOL_GPL(get_device); | |
727 | EXPORT_SYMBOL_GPL(put_device); | |
1da177e4 LT |
728 | |
729 | EXPORT_SYMBOL_GPL(device_create_file); | |
730 | EXPORT_SYMBOL_GPL(device_remove_file); | |
23681e47 GKH |
731 | |
732 | ||
733 | static void device_create_release(struct device *dev) | |
734 | { | |
735 | pr_debug("%s called for %s\n", __FUNCTION__, dev->bus_id); | |
736 | kfree(dev); | |
737 | } | |
738 | ||
739 | /** | |
740 | * device_create - creates a device and registers it with sysfs | |
42734daf HK |
741 | * @class: pointer to the struct class that this device should be registered to |
742 | * @parent: pointer to the parent struct device of this new device, if any | |
743 | * @devt: the dev_t for the char device to be added | |
744 | * @fmt: string for the device's name | |
745 | * | |
746 | * This function can be used by char device classes. A struct device | |
747 | * will be created in sysfs, registered to the specified class. | |
23681e47 | 748 | * |
23681e47 GKH |
749 | * A "dev" file will be created, showing the dev_t for the device, if |
750 | * the dev_t is not 0,0. | |
42734daf HK |
751 | * If a pointer to a parent struct device is passed in, the newly created |
752 | * struct device will be a child of that device in sysfs. | |
753 | * The pointer to the struct device will be returned from the call. | |
754 | * Any further sysfs files that might be required can be created using this | |
23681e47 GKH |
755 | * pointer. |
756 | * | |
757 | * Note: the struct class passed to this function must have previously | |
758 | * been created with a call to class_create(). | |
759 | */ | |
760 | struct device *device_create(struct class *class, struct device *parent, | |
5cbe5f8a | 761 | dev_t devt, const char *fmt, ...) |
23681e47 GKH |
762 | { |
763 | va_list args; | |
764 | struct device *dev = NULL; | |
765 | int retval = -ENODEV; | |
766 | ||
767 | if (class == NULL || IS_ERR(class)) | |
768 | goto error; | |
23681e47 GKH |
769 | |
770 | dev = kzalloc(sizeof(*dev), GFP_KERNEL); | |
771 | if (!dev) { | |
772 | retval = -ENOMEM; | |
773 | goto error; | |
774 | } | |
775 | ||
776 | dev->devt = devt; | |
777 | dev->class = class; | |
778 | dev->parent = parent; | |
779 | dev->release = device_create_release; | |
780 | ||
781 | va_start(args, fmt); | |
782 | vsnprintf(dev->bus_id, BUS_ID_SIZE, fmt, args); | |
783 | va_end(args); | |
784 | retval = device_register(dev); | |
785 | if (retval) | |
786 | goto error; | |
787 | ||
23681e47 GKH |
788 | return dev; |
789 | ||
790 | error: | |
791 | kfree(dev); | |
792 | return ERR_PTR(retval); | |
793 | } | |
794 | EXPORT_SYMBOL_GPL(device_create); | |
795 | ||
796 | /** | |
797 | * device_destroy - removes a device that was created with device_create() | |
42734daf HK |
798 | * @class: pointer to the struct class that this device was registered with |
799 | * @devt: the dev_t of the device that was previously registered | |
23681e47 | 800 | * |
42734daf HK |
801 | * This call unregisters and cleans up a device that was created with a |
802 | * call to device_create(). | |
23681e47 GKH |
803 | */ |
804 | void device_destroy(struct class *class, dev_t devt) | |
805 | { | |
806 | struct device *dev = NULL; | |
807 | struct device *dev_tmp; | |
808 | ||
809 | down(&class->sem); | |
810 | list_for_each_entry(dev_tmp, &class->devices, node) { | |
811 | if (dev_tmp->devt == devt) { | |
812 | dev = dev_tmp; | |
813 | break; | |
814 | } | |
815 | } | |
816 | up(&class->sem); | |
817 | ||
5d9fd169 | 818 | if (dev) |
23681e47 | 819 | device_unregister(dev); |
23681e47 GKH |
820 | } |
821 | EXPORT_SYMBOL_GPL(device_destroy); | |
a2de48ca GKH |
822 | |
823 | /** | |
824 | * device_rename - renames a device | |
825 | * @dev: the pointer to the struct device to be renamed | |
826 | * @new_name: the new name of the device | |
827 | */ | |
828 | int device_rename(struct device *dev, char *new_name) | |
829 | { | |
830 | char *old_class_name = NULL; | |
831 | char *new_class_name = NULL; | |
832 | char *old_symlink_name = NULL; | |
833 | int error; | |
834 | ||
835 | dev = get_device(dev); | |
836 | if (!dev) | |
837 | return -EINVAL; | |
838 | ||
839 | pr_debug("DEVICE: renaming '%s' to '%s'\n", dev->bus_id, new_name); | |
840 | ||
841 | if ((dev->class) && (dev->parent)) | |
842 | old_class_name = make_class_name(dev->class->name, &dev->kobj); | |
843 | ||
844 | if (dev->class) { | |
845 | old_symlink_name = kmalloc(BUS_ID_SIZE, GFP_KERNEL); | |
952ab431 JJ |
846 | if (!old_symlink_name) { |
847 | error = -ENOMEM; | |
848 | goto out_free_old_class; | |
849 | } | |
a2de48ca GKH |
850 | strlcpy(old_symlink_name, dev->bus_id, BUS_ID_SIZE); |
851 | } | |
852 | ||
853 | strlcpy(dev->bus_id, new_name, BUS_ID_SIZE); | |
854 | ||
855 | error = kobject_rename(&dev->kobj, new_name); | |
856 | ||
857 | if (old_class_name) { | |
858 | new_class_name = make_class_name(dev->class->name, &dev->kobj); | |
859 | if (new_class_name) { | |
860 | sysfs_create_link(&dev->parent->kobj, &dev->kobj, | |
861 | new_class_name); | |
862 | sysfs_remove_link(&dev->parent->kobj, old_class_name); | |
863 | } | |
864 | } | |
865 | if (dev->class) { | |
866 | sysfs_remove_link(&dev->class->subsys.kset.kobj, | |
867 | old_symlink_name); | |
868 | sysfs_create_link(&dev->class->subsys.kset.kobj, &dev->kobj, | |
869 | dev->bus_id); | |
870 | } | |
871 | put_device(dev); | |
872 | ||
a2de48ca GKH |
873 | kfree(new_class_name); |
874 | kfree(old_symlink_name); | |
952ab431 JJ |
875 | out_free_old_class: |
876 | kfree(old_class_name); | |
a2de48ca GKH |
877 | |
878 | return error; | |
879 | } |