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1da177e4 LT |
1 | /* |
2 | * sys.c - pseudo-bus for system 'devices' (cpus, PICs, timers, etc) | |
3 | * | |
4 | * Copyright (c) 2002-3 Patrick Mochel | |
5 | * 2002-3 Open Source Development Lab | |
6 | * | |
7 | * This file is released under the GPLv2 | |
8 | * | |
9 | * This exports a 'system' bus type. | |
10 | * By default, a 'sys' bus gets added to the root of the system. There will | |
11 | * always be core system devices. Devices can use sysdev_register() to | |
12 | * add themselves as children of the system bus. | |
13 | */ | |
14 | ||
1da177e4 LT |
15 | #include <linux/sysdev.h> |
16 | #include <linux/err.h> | |
17 | #include <linux/module.h> | |
18 | #include <linux/kernel.h> | |
19 | #include <linux/init.h> | |
20 | #include <linux/slab.h> | |
21 | #include <linux/string.h> | |
438510f6 | 22 | #include <linux/pm.h> |
f67d115f | 23 | #include <linux/device.h> |
9f3f776b | 24 | #include <linux/mutex.h> |
1da177e4 | 25 | |
f67d115f AB |
26 | #include "base.h" |
27 | ||
1da177e4 LT |
28 | #define to_sysdev(k) container_of(k, struct sys_device, kobj) |
29 | #define to_sysdev_attr(a) container_of(a, struct sysdev_attribute, attr) | |
30 | ||
31 | ||
32 | static ssize_t | |
33 | sysdev_show(struct kobject * kobj, struct attribute * attr, char * buffer) | |
34 | { | |
35 | struct sys_device * sysdev = to_sysdev(kobj); | |
36 | struct sysdev_attribute * sysdev_attr = to_sysdev_attr(attr); | |
37 | ||
38 | if (sysdev_attr->show) | |
39 | return sysdev_attr->show(sysdev, buffer); | |
4a0c20bf | 40 | return -EIO; |
1da177e4 LT |
41 | } |
42 | ||
43 | ||
44 | static ssize_t | |
45 | sysdev_store(struct kobject * kobj, struct attribute * attr, | |
46 | const char * buffer, size_t count) | |
47 | { | |
48 | struct sys_device * sysdev = to_sysdev(kobj); | |
49 | struct sysdev_attribute * sysdev_attr = to_sysdev_attr(attr); | |
50 | ||
51 | if (sysdev_attr->store) | |
52 | return sysdev_attr->store(sysdev, buffer, count); | |
4a0c20bf | 53 | return -EIO; |
1da177e4 LT |
54 | } |
55 | ||
56 | static struct sysfs_ops sysfs_ops = { | |
57 | .show = sysdev_show, | |
58 | .store = sysdev_store, | |
59 | }; | |
60 | ||
61 | static struct kobj_type ktype_sysdev = { | |
62 | .sysfs_ops = &sysfs_ops, | |
63 | }; | |
64 | ||
65 | ||
66 | int sysdev_create_file(struct sys_device * s, struct sysdev_attribute * a) | |
67 | { | |
68 | return sysfs_create_file(&s->kobj, &a->attr); | |
69 | } | |
70 | ||
71 | ||
72 | void sysdev_remove_file(struct sys_device * s, struct sysdev_attribute * a) | |
73 | { | |
74 | sysfs_remove_file(&s->kobj, &a->attr); | |
75 | } | |
76 | ||
77 | EXPORT_SYMBOL_GPL(sysdev_create_file); | |
78 | EXPORT_SYMBOL_GPL(sysdev_remove_file); | |
79 | ||
670dd90d SL |
80 | #define to_sysdev_class(k) container_of(k, struct sysdev_class, kset.kobj) |
81 | #define to_sysdev_class_attr(a) container_of(a, \ | |
82 | struct sysdev_class_attribute, attr) | |
83 | ||
84 | static ssize_t sysdev_class_show(struct kobject *kobj, struct attribute *attr, | |
85 | char *buffer) | |
86 | { | |
87 | struct sysdev_class * class = to_sysdev_class(kobj); | |
88 | struct sysdev_class_attribute *class_attr = to_sysdev_class_attr(attr); | |
89 | ||
90 | if (class_attr->show) | |
91 | return class_attr->show(class, buffer); | |
92 | return -EIO; | |
93 | } | |
94 | ||
95 | static ssize_t sysdev_class_store(struct kobject *kobj, struct attribute *attr, | |
96 | const char *buffer, size_t count) | |
97 | { | |
98 | struct sysdev_class * class = to_sysdev_class(kobj); | |
99 | struct sysdev_class_attribute * class_attr = to_sysdev_class_attr(attr); | |
100 | ||
101 | if (class_attr->store) | |
102 | return class_attr->store(class, buffer, count); | |
103 | return -EIO; | |
104 | } | |
105 | ||
106 | static struct sysfs_ops sysfs_class_ops = { | |
107 | .show = sysdev_class_show, | |
108 | .store = sysdev_class_store, | |
109 | }; | |
110 | ||
111 | static struct kobj_type ktype_sysdev_class = { | |
112 | .sysfs_ops = &sysfs_class_ops, | |
113 | }; | |
114 | ||
115 | int sysdev_class_create_file(struct sysdev_class *c, | |
116 | struct sysdev_class_attribute *a) | |
117 | { | |
118 | return sysfs_create_file(&c->kset.kobj, &a->attr); | |
119 | } | |
120 | EXPORT_SYMBOL_GPL(sysdev_class_create_file); | |
121 | ||
122 | void sysdev_class_remove_file(struct sysdev_class *c, | |
123 | struct sysdev_class_attribute *a) | |
124 | { | |
125 | sysfs_remove_file(&c->kset.kobj, &a->attr); | |
126 | } | |
127 | EXPORT_SYMBOL_GPL(sysdev_class_remove_file); | |
128 | ||
aade4041 | 129 | static struct kset *system_kset; |
1da177e4 LT |
130 | |
131 | int sysdev_class_register(struct sysdev_class * cls) | |
132 | { | |
133 | pr_debug("Registering sysdev class '%s'\n", | |
134 | kobject_name(&cls->kset.kobj)); | |
135 | INIT_LIST_HEAD(&cls->drivers); | |
aade4041 | 136 | cls->kset.kobj.parent = &system_kset->kobj; |
3514faca | 137 | cls->kset.kobj.ktype = &ktype_sysdev_class; |
aade4041 | 138 | cls->kset.kobj.kset = system_kset; |
1da177e4 LT |
139 | return kset_register(&cls->kset); |
140 | } | |
141 | ||
142 | void sysdev_class_unregister(struct sysdev_class * cls) | |
143 | { | |
144 | pr_debug("Unregistering sysdev class '%s'\n", | |
145 | kobject_name(&cls->kset.kobj)); | |
146 | kset_unregister(&cls->kset); | |
147 | } | |
148 | ||
149 | EXPORT_SYMBOL_GPL(sysdev_class_register); | |
150 | EXPORT_SYMBOL_GPL(sysdev_class_unregister); | |
151 | ||
9f3f776b | 152 | static DEFINE_MUTEX(sysdev_drivers_lock); |
1da177e4 LT |
153 | |
154 | /** | |
155 | * sysdev_driver_register - Register auxillary driver | |
44b760a8 | 156 | * @cls: Device class driver belongs to. |
1da177e4 LT |
157 | * @drv: Driver. |
158 | * | |
44b760a8 | 159 | * @drv is inserted into @cls->drivers to be |
1da177e4 LT |
160 | * called on each operation on devices of that class. The refcount |
161 | * of @cls is incremented. | |
1da177e4 LT |
162 | */ |
163 | ||
44b760a8 | 164 | int sysdev_driver_register(struct sysdev_class *cls, struct sysdev_driver *drv) |
1da177e4 | 165 | { |
44b760a8 AM |
166 | int err = 0; |
167 | ||
9f3f776b | 168 | mutex_lock(&sysdev_drivers_lock); |
1da177e4 LT |
169 | if (cls && kset_get(&cls->kset)) { |
170 | list_add_tail(&drv->entry, &cls->drivers); | |
171 | ||
172 | /* If devices of this class already exist, tell the driver */ | |
173 | if (drv->add) { | |
174 | struct sys_device *dev; | |
175 | list_for_each_entry(dev, &cls->kset.list, kobj.entry) | |
176 | drv->add(dev); | |
177 | } | |
44b760a8 AM |
178 | } else { |
179 | err = -EINVAL; | |
180 | printk(KERN_ERR "%s: invalid device class\n", __FUNCTION__); | |
181 | WARN_ON(1); | |
182 | } | |
9f3f776b | 183 | mutex_unlock(&sysdev_drivers_lock); |
44b760a8 | 184 | return err; |
1da177e4 LT |
185 | } |
186 | ||
187 | ||
188 | /** | |
189 | * sysdev_driver_unregister - Remove an auxillary driver. | |
190 | * @cls: Class driver belongs to. | |
191 | * @drv: Driver. | |
192 | */ | |
193 | void sysdev_driver_unregister(struct sysdev_class * cls, | |
194 | struct sysdev_driver * drv) | |
195 | { | |
9f3f776b | 196 | mutex_lock(&sysdev_drivers_lock); |
1da177e4 LT |
197 | list_del_init(&drv->entry); |
198 | if (cls) { | |
199 | if (drv->remove) { | |
200 | struct sys_device *dev; | |
201 | list_for_each_entry(dev, &cls->kset.list, kobj.entry) | |
202 | drv->remove(dev); | |
203 | } | |
204 | kset_put(&cls->kset); | |
205 | } | |
9f3f776b | 206 | mutex_unlock(&sysdev_drivers_lock); |
1da177e4 LT |
207 | } |
208 | ||
209 | EXPORT_SYMBOL_GPL(sysdev_driver_register); | |
210 | EXPORT_SYMBOL_GPL(sysdev_driver_unregister); | |
211 | ||
212 | ||
213 | ||
214 | /** | |
215 | * sysdev_register - add a system device to the tree | |
216 | * @sysdev: device in question | |
217 | * | |
218 | */ | |
219 | int sysdev_register(struct sys_device * sysdev) | |
220 | { | |
221 | int error; | |
222 | struct sysdev_class * cls = sysdev->cls; | |
223 | ||
224 | if (!cls) | |
225 | return -EINVAL; | |
226 | ||
61030bfb GKH |
227 | pr_debug("Registering sys device '%s'\n", kobject_name(&sysdev->kobj)); |
228 | ||
1da177e4 LT |
229 | /* Make sure the kset is set */ |
230 | sysdev->kobj.kset = &cls->kset; | |
231 | ||
1da177e4 | 232 | /* Register the object */ |
61030bfb GKH |
233 | error = kobject_init_and_add(&sysdev->kobj, &ktype_sysdev, NULL, |
234 | "%s%d", kobject_name(&cls->kset.kobj), | |
235 | sysdev->id); | |
1da177e4 LT |
236 | |
237 | if (!error) { | |
238 | struct sysdev_driver * drv; | |
239 | ||
9f3f776b | 240 | mutex_lock(&sysdev_drivers_lock); |
1da177e4 LT |
241 | /* Generic notification is implicit, because it's that |
242 | * code that should have called us. | |
243 | */ | |
244 | ||
1da177e4 LT |
245 | /* Notify class auxillary drivers */ |
246 | list_for_each_entry(drv, &cls->drivers, entry) { | |
247 | if (drv->add) | |
248 | drv->add(sysdev); | |
249 | } | |
9f3f776b | 250 | mutex_unlock(&sysdev_drivers_lock); |
1da177e4 | 251 | } |
61030bfb | 252 | kobject_uevent(&sysdev->kobj, KOBJ_ADD); |
1da177e4 LT |
253 | return error; |
254 | } | |
255 | ||
256 | void sysdev_unregister(struct sys_device * sysdev) | |
257 | { | |
258 | struct sysdev_driver * drv; | |
259 | ||
9f3f776b | 260 | mutex_lock(&sysdev_drivers_lock); |
1da177e4 LT |
261 | list_for_each_entry(drv, &sysdev->cls->drivers, entry) { |
262 | if (drv->remove) | |
263 | drv->remove(sysdev); | |
264 | } | |
9f3f776b | 265 | mutex_unlock(&sysdev_drivers_lock); |
1da177e4 | 266 | |
c10997f6 | 267 | kobject_put(&sysdev->kobj); |
1da177e4 LT |
268 | } |
269 | ||
270 | ||
271 | ||
272 | /** | |
273 | * sysdev_shutdown - Shut down all system devices. | |
274 | * | |
275 | * Loop over each class of system devices, and the devices in each | |
276 | * of those classes. For each device, we call the shutdown method for | |
44b760a8 | 277 | * each driver registered for the device - the auxillaries, |
1da177e4 LT |
278 | * and the class driver. |
279 | * | |
280 | * Note: The list is iterated in reverse order, so that we shut down | |
281 | * child devices before we shut down thier parents. The list ordering | |
282 | * is guaranteed by virtue of the fact that child devices are registered | |
283 | * after their parents. | |
284 | */ | |
285 | ||
286 | void sysdev_shutdown(void) | |
287 | { | |
288 | struct sysdev_class * cls; | |
289 | ||
290 | pr_debug("Shutting Down System Devices\n"); | |
291 | ||
9f3f776b | 292 | mutex_lock(&sysdev_drivers_lock); |
aade4041 | 293 | list_for_each_entry_reverse(cls, &system_kset->list, kset.kobj.entry) { |
1da177e4 LT |
294 | struct sys_device * sysdev; |
295 | ||
296 | pr_debug("Shutting down type '%s':\n", | |
297 | kobject_name(&cls->kset.kobj)); | |
298 | ||
299 | list_for_each_entry(sysdev, &cls->kset.list, kobj.entry) { | |
300 | struct sysdev_driver * drv; | |
301 | pr_debug(" %s\n", kobject_name(&sysdev->kobj)); | |
302 | ||
44b760a8 | 303 | /* Call auxillary drivers first */ |
1da177e4 LT |
304 | list_for_each_entry(drv, &cls->drivers, entry) { |
305 | if (drv->shutdown) | |
306 | drv->shutdown(sysdev); | |
307 | } | |
308 | ||
309 | /* Now call the generic one */ | |
310 | if (cls->shutdown) | |
311 | cls->shutdown(sysdev); | |
312 | } | |
313 | } | |
9f3f776b | 314 | mutex_unlock(&sysdev_drivers_lock); |
1da177e4 LT |
315 | } |
316 | ||
ceaeade1 SL |
317 | static void __sysdev_resume(struct sys_device *dev) |
318 | { | |
319 | struct sysdev_class *cls = dev->cls; | |
320 | struct sysdev_driver *drv; | |
321 | ||
322 | /* First, call the class-specific one */ | |
323 | if (cls->resume) | |
324 | cls->resume(dev); | |
325 | ||
326 | /* Call auxillary drivers next. */ | |
327 | list_for_each_entry(drv, &cls->drivers, entry) { | |
328 | if (drv->resume) | |
329 | drv->resume(dev); | |
330 | } | |
ceaeade1 | 331 | } |
1da177e4 LT |
332 | |
333 | /** | |
334 | * sysdev_suspend - Suspend all system devices. | |
335 | * @state: Power state to enter. | |
336 | * | |
337 | * We perform an almost identical operation as sys_device_shutdown() | |
338 | * above, though calling ->suspend() instead. Interrupts are disabled | |
339 | * when this called. Devices are responsible for both saving state and | |
340 | * quiescing or powering down the device. | |
341 | * | |
342 | * This is only called by the device PM core, so we let them handle | |
343 | * all synchronization. | |
344 | */ | |
345 | ||
438510f6 | 346 | int sysdev_suspend(pm_message_t state) |
1da177e4 LT |
347 | { |
348 | struct sysdev_class * cls; | |
ceaeade1 SL |
349 | struct sys_device *sysdev, *err_dev; |
350 | struct sysdev_driver *drv, *err_drv; | |
351 | int ret; | |
1da177e4 LT |
352 | |
353 | pr_debug("Suspending System Devices\n"); | |
354 | ||
aade4041 | 355 | list_for_each_entry_reverse(cls, &system_kset->list, kset.kobj.entry) { |
1da177e4 LT |
356 | pr_debug("Suspending type '%s':\n", |
357 | kobject_name(&cls->kset.kobj)); | |
358 | ||
359 | list_for_each_entry(sysdev, &cls->kset.list, kobj.entry) { | |
1da177e4 LT |
360 | pr_debug(" %s\n", kobject_name(&sysdev->kobj)); |
361 | ||
44b760a8 | 362 | /* Call auxillary drivers first */ |
1da177e4 | 363 | list_for_each_entry(drv, &cls->drivers, entry) { |
ceaeade1 SL |
364 | if (drv->suspend) { |
365 | ret = drv->suspend(sysdev, state); | |
366 | if (ret) | |
367 | goto aux_driver; | |
368 | } | |
1da177e4 LT |
369 | } |
370 | ||
371 | /* Now call the generic one */ | |
ceaeade1 SL |
372 | if (cls->suspend) { |
373 | ret = cls->suspend(sysdev, state); | |
374 | if (ret) | |
375 | goto cls_driver; | |
376 | } | |
1da177e4 LT |
377 | } |
378 | } | |
379 | return 0; | |
ceaeade1 SL |
380 | /* resume current sysdev */ |
381 | cls_driver: | |
382 | drv = NULL; | |
383 | printk(KERN_ERR "Class suspend failed for %s\n", | |
384 | kobject_name(&sysdev->kobj)); | |
385 | ||
386 | aux_driver: | |
387 | if (drv) | |
388 | printk(KERN_ERR "Class driver suspend failed for %s\n", | |
389 | kobject_name(&sysdev->kobj)); | |
390 | list_for_each_entry(err_drv, &cls->drivers, entry) { | |
391 | if (err_drv == drv) | |
392 | break; | |
393 | if (err_drv->resume) | |
394 | err_drv->resume(sysdev); | |
395 | } | |
ceaeade1 | 396 | |
ceaeade1 SL |
397 | /* resume other sysdevs in current class */ |
398 | list_for_each_entry(err_dev, &cls->kset.list, kobj.entry) { | |
399 | if (err_dev == sysdev) | |
400 | break; | |
401 | pr_debug(" %s\n", kobject_name(&err_dev->kobj)); | |
402 | __sysdev_resume(err_dev); | |
403 | } | |
404 | ||
405 | /* resume other classes */ | |
aade4041 | 406 | list_for_each_entry_continue(cls, &system_kset->list, kset.kobj.entry) { |
ceaeade1 SL |
407 | list_for_each_entry(err_dev, &cls->kset.list, kobj.entry) { |
408 | pr_debug(" %s\n", kobject_name(&err_dev->kobj)); | |
409 | __sysdev_resume(err_dev); | |
410 | } | |
411 | } | |
412 | return ret; | |
1da177e4 LT |
413 | } |
414 | ||
415 | ||
416 | /** | |
417 | * sysdev_resume - Bring system devices back to life. | |
418 | * | |
419 | * Similar to sys_device_suspend(), but we iterate the list forwards | |
420 | * to guarantee that parent devices are resumed before their children. | |
421 | * | |
422 | * Note: Interrupts are disabled when called. | |
423 | */ | |
424 | ||
425 | int sysdev_resume(void) | |
426 | { | |
427 | struct sysdev_class * cls; | |
428 | ||
429 | pr_debug("Resuming System Devices\n"); | |
430 | ||
aade4041 | 431 | list_for_each_entry(cls, &system_kset->list, kset.kobj.entry) { |
1da177e4 LT |
432 | struct sys_device * sysdev; |
433 | ||
434 | pr_debug("Resuming type '%s':\n", | |
435 | kobject_name(&cls->kset.kobj)); | |
436 | ||
437 | list_for_each_entry(sysdev, &cls->kset.list, kobj.entry) { | |
1da177e4 LT |
438 | pr_debug(" %s\n", kobject_name(&sysdev->kobj)); |
439 | ||
ceaeade1 | 440 | __sysdev_resume(sysdev); |
1da177e4 LT |
441 | } |
442 | } | |
443 | return 0; | |
444 | } | |
445 | ||
446 | ||
447 | int __init system_bus_init(void) | |
448 | { | |
aade4041 GKH |
449 | system_kset = kset_create_and_add("system", NULL, &devices_kset->kobj); |
450 | if (!system_kset) | |
451 | return -ENOMEM; | |
452 | return 0; | |
1da177e4 LT |
453 | } |
454 | ||
455 | EXPORT_SYMBOL_GPL(sysdev_register); | |
456 | EXPORT_SYMBOL_GPL(sysdev_unregister); |