[PATCH] h8300 header update
[linux-3.10.git] / drivers / base / sys.c
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
15 #include <linux/config.h>
16 #include <linux/sysdev.h>
17 #include <linux/err.h>
18 #include <linux/module.h>
19 #include <linux/kernel.h>
20 #include <linux/init.h>
21 #include <linux/slab.h>
22 #include <linux/string.h>
23
24
25 extern struct subsystem devices_subsys;
26
27 #define to_sysdev(k) container_of(k, struct sys_device, kobj)
28 #define to_sysdev_attr(a) container_of(a, struct sysdev_attribute, attr)
29
30
31 static ssize_t
32 sysdev_show(struct kobject * kobj, struct attribute * attr, char * buffer)
33 {
34         struct sys_device * sysdev = to_sysdev(kobj);
35         struct sysdev_attribute * sysdev_attr = to_sysdev_attr(attr);
36
37         if (sysdev_attr->show)
38                 return sysdev_attr->show(sysdev, buffer);
39         return 0;
40 }
41
42
43 static ssize_t
44 sysdev_store(struct kobject * kobj, struct attribute * attr,
45              const char * buffer, size_t count)
46 {
47         struct sys_device * sysdev = to_sysdev(kobj);
48         struct sysdev_attribute * sysdev_attr = to_sysdev_attr(attr);
49
50         if (sysdev_attr->store)
51                 return sysdev_attr->store(sysdev, buffer, count);
52         return 0;
53 }
54
55 static struct sysfs_ops sysfs_ops = {
56         .show   = sysdev_show,
57         .store  = sysdev_store,
58 };
59
60 static struct kobj_type ktype_sysdev = {
61         .sysfs_ops      = &sysfs_ops,
62 };
63
64
65 int sysdev_create_file(struct sys_device * s, struct sysdev_attribute * a)
66 {
67         return sysfs_create_file(&s->kobj, &a->attr);
68 }
69
70
71 void sysdev_remove_file(struct sys_device * s, struct sysdev_attribute * a)
72 {
73         sysfs_remove_file(&s->kobj, &a->attr);
74 }
75
76 EXPORT_SYMBOL_GPL(sysdev_create_file);
77 EXPORT_SYMBOL_GPL(sysdev_remove_file);
78
79 /*
80  * declare system_subsys
81  */
82 static decl_subsys(system, &ktype_sysdev, NULL);
83
84 int sysdev_class_register(struct sysdev_class * cls)
85 {
86         pr_debug("Registering sysdev class '%s'\n",
87                  kobject_name(&cls->kset.kobj));
88         INIT_LIST_HEAD(&cls->drivers);
89         cls->kset.subsys = &system_subsys;
90         kset_set_kset_s(cls, system_subsys);
91         return kset_register(&cls->kset);
92 }
93
94 void sysdev_class_unregister(struct sysdev_class * cls)
95 {
96         pr_debug("Unregistering sysdev class '%s'\n",
97                  kobject_name(&cls->kset.kobj));
98         kset_unregister(&cls->kset);
99 }
100
101 EXPORT_SYMBOL_GPL(sysdev_class_register);
102 EXPORT_SYMBOL_GPL(sysdev_class_unregister);
103
104
105 static LIST_HEAD(sysdev_drivers);
106 static DECLARE_MUTEX(sysdev_drivers_lock);
107
108 /**
109  *      sysdev_driver_register - Register auxillary driver
110  *      @cls:   Device class driver belongs to.
111  *      @drv:   Driver.
112  *
113  *      If @cls is valid, then @drv is inserted into @cls->drivers to be
114  *      called on each operation on devices of that class. The refcount
115  *      of @cls is incremented.
116  *      Otherwise, @drv is inserted into sysdev_drivers, and called for
117  *      each device.
118  */
119
120 int sysdev_driver_register(struct sysdev_class * cls,
121                            struct sysdev_driver * drv)
122 {
123         down(&sysdev_drivers_lock);
124         if (cls && kset_get(&cls->kset)) {
125                 list_add_tail(&drv->entry, &cls->drivers);
126
127                 /* If devices of this class already exist, tell the driver */
128                 if (drv->add) {
129                         struct sys_device *dev;
130                         list_for_each_entry(dev, &cls->kset.list, kobj.entry)
131                                 drv->add(dev);
132                 }
133         } else
134                 list_add_tail(&drv->entry, &sysdev_drivers);
135         up(&sysdev_drivers_lock);
136         return 0;
137 }
138
139
140 /**
141  *      sysdev_driver_unregister - Remove an auxillary driver.
142  *      @cls:   Class driver belongs to.
143  *      @drv:   Driver.
144  */
145 void sysdev_driver_unregister(struct sysdev_class * cls,
146                               struct sysdev_driver * drv)
147 {
148         down(&sysdev_drivers_lock);
149         list_del_init(&drv->entry);
150         if (cls) {
151                 if (drv->remove) {
152                         struct sys_device *dev;
153                         list_for_each_entry(dev, &cls->kset.list, kobj.entry)
154                                 drv->remove(dev);
155                 }
156                 kset_put(&cls->kset);
157         }
158         up(&sysdev_drivers_lock);
159 }
160
161 EXPORT_SYMBOL_GPL(sysdev_driver_register);
162 EXPORT_SYMBOL_GPL(sysdev_driver_unregister);
163
164
165
166 /**
167  *      sysdev_register - add a system device to the tree
168  *      @sysdev:        device in question
169  *
170  */
171 int sysdev_register(struct sys_device * sysdev)
172 {
173         int error;
174         struct sysdev_class * cls = sysdev->cls;
175
176         if (!cls)
177                 return -EINVAL;
178
179         /* Make sure the kset is set */
180         sysdev->kobj.kset = &cls->kset;
181
182         /* But make sure we point to the right type for sysfs translation */
183         sysdev->kobj.ktype = &ktype_sysdev;
184         error = kobject_set_name(&sysdev->kobj, "%s%d",
185                          kobject_name(&cls->kset.kobj), sysdev->id);
186         if (error)
187                 return error;
188
189         pr_debug("Registering sys device '%s'\n", kobject_name(&sysdev->kobj));
190
191         /* Register the object */
192         error = kobject_register(&sysdev->kobj);
193
194         if (!error) {
195                 struct sysdev_driver * drv;
196
197                 down(&sysdev_drivers_lock);
198                 /* Generic notification is implicit, because it's that
199                  * code that should have called us.
200                  */
201
202                 /* Notify global drivers */
203                 list_for_each_entry(drv, &sysdev_drivers, entry) {
204                         if (drv->add)
205                                 drv->add(sysdev);
206                 }
207
208                 /* Notify class auxillary drivers */
209                 list_for_each_entry(drv, &cls->drivers, entry) {
210                         if (drv->add)
211                                 drv->add(sysdev);
212                 }
213                 up(&sysdev_drivers_lock);
214         }
215         return error;
216 }
217
218 void sysdev_unregister(struct sys_device * sysdev)
219 {
220         struct sysdev_driver * drv;
221
222         down(&sysdev_drivers_lock);
223         list_for_each_entry(drv, &sysdev_drivers, entry) {
224                 if (drv->remove)
225                         drv->remove(sysdev);
226         }
227
228         list_for_each_entry(drv, &sysdev->cls->drivers, entry) {
229                 if (drv->remove)
230                         drv->remove(sysdev);
231         }
232         up(&sysdev_drivers_lock);
233
234         kobject_unregister(&sysdev->kobj);
235 }
236
237
238
239 /**
240  *      sysdev_shutdown - Shut down all system devices.
241  *
242  *      Loop over each class of system devices, and the devices in each
243  *      of those classes. For each device, we call the shutdown method for
244  *      each driver registered for the device - the globals, the auxillaries,
245  *      and the class driver.
246  *
247  *      Note: The list is iterated in reverse order, so that we shut down
248  *      child devices before we shut down thier parents. The list ordering
249  *      is guaranteed by virtue of the fact that child devices are registered
250  *      after their parents.
251  */
252
253 void sysdev_shutdown(void)
254 {
255         struct sysdev_class * cls;
256
257         pr_debug("Shutting Down System Devices\n");
258
259         down(&sysdev_drivers_lock);
260         list_for_each_entry_reverse(cls, &system_subsys.kset.list,
261                                     kset.kobj.entry) {
262                 struct sys_device * sysdev;
263
264                 pr_debug("Shutting down type '%s':\n",
265                          kobject_name(&cls->kset.kobj));
266
267                 list_for_each_entry(sysdev, &cls->kset.list, kobj.entry) {
268                         struct sysdev_driver * drv;
269                         pr_debug(" %s\n", kobject_name(&sysdev->kobj));
270
271                         /* Call global drivers first. */
272                         list_for_each_entry(drv, &sysdev_drivers, entry) {
273                                 if (drv->shutdown)
274                                         drv->shutdown(sysdev);
275                         }
276
277                         /* Call auxillary drivers next. */
278                         list_for_each_entry(drv, &cls->drivers, entry) {
279                                 if (drv->shutdown)
280                                         drv->shutdown(sysdev);
281                         }
282
283                         /* Now call the generic one */
284                         if (cls->shutdown)
285                                 cls->shutdown(sysdev);
286                 }
287         }
288         up(&sysdev_drivers_lock);
289 }
290
291
292 /**
293  *      sysdev_suspend - Suspend all system devices.
294  *      @state:         Power state to enter.
295  *
296  *      We perform an almost identical operation as sys_device_shutdown()
297  *      above, though calling ->suspend() instead. Interrupts are disabled
298  *      when this called. Devices are responsible for both saving state and
299  *      quiescing or powering down the device.
300  *
301  *      This is only called by the device PM core, so we let them handle
302  *      all synchronization.
303  */
304
305 int sysdev_suspend(u32 state)
306 {
307         struct sysdev_class * cls;
308
309         pr_debug("Suspending System Devices\n");
310
311         list_for_each_entry_reverse(cls, &system_subsys.kset.list,
312                                     kset.kobj.entry) {
313                 struct sys_device * sysdev;
314
315                 pr_debug("Suspending type '%s':\n",
316                          kobject_name(&cls->kset.kobj));
317
318                 list_for_each_entry(sysdev, &cls->kset.list, kobj.entry) {
319                         struct sysdev_driver * drv;
320                         pr_debug(" %s\n", kobject_name(&sysdev->kobj));
321
322                         /* Call global drivers first. */
323                         list_for_each_entry(drv, &sysdev_drivers, entry) {
324                                 if (drv->suspend)
325                                         drv->suspend(sysdev, state);
326                         }
327
328                         /* Call auxillary drivers next. */
329                         list_for_each_entry(drv, &cls->drivers, entry) {
330                                 if (drv->suspend)
331                                         drv->suspend(sysdev, state);
332                         }
333
334                         /* Now call the generic one */
335                         if (cls->suspend)
336                                 cls->suspend(sysdev, state);
337                 }
338         }
339         return 0;
340 }
341
342
343 /**
344  *      sysdev_resume - Bring system devices back to life.
345  *
346  *      Similar to sys_device_suspend(), but we iterate the list forwards
347  *      to guarantee that parent devices are resumed before their children.
348  *
349  *      Note: Interrupts are disabled when called.
350  */
351
352 int sysdev_resume(void)
353 {
354         struct sysdev_class * cls;
355
356         pr_debug("Resuming System Devices\n");
357
358         list_for_each_entry(cls, &system_subsys.kset.list, kset.kobj.entry) {
359                 struct sys_device * sysdev;
360
361                 pr_debug("Resuming type '%s':\n",
362                          kobject_name(&cls->kset.kobj));
363
364                 list_for_each_entry(sysdev, &cls->kset.list, kobj.entry) {
365                         struct sysdev_driver * drv;
366                         pr_debug(" %s\n", kobject_name(&sysdev->kobj));
367
368                         /* First, call the class-specific one */
369                         if (cls->resume)
370                                 cls->resume(sysdev);
371
372                         /* Call auxillary drivers next. */
373                         list_for_each_entry(drv, &cls->drivers, entry) {
374                                 if (drv->resume)
375                                         drv->resume(sysdev);
376                         }
377
378                         /* Call global drivers. */
379                         list_for_each_entry(drv, &sysdev_drivers, entry) {
380                                 if (drv->resume)
381                                         drv->resume(sysdev);
382                         }
383
384                 }
385         }
386         return 0;
387 }
388
389
390 int __init system_bus_init(void)
391 {
392         system_subsys.kset.kobj.parent = &devices_subsys.kset.kobj;
393         return subsystem_register(&system_subsys);
394 }
395
396 EXPORT_SYMBOL_GPL(sysdev_register);
397 EXPORT_SYMBOL_GPL(sysdev_unregister);