ARM: JIVE: Update mach-jive to use gpiolib API
[linux-2.6/linux-acpi-2.6/ibm-acpi-2.6.git] / drivers / base / sys.c
blob9354dc10a3635b25e87ca10fe92babffb9faba9d
1 /*
2 * sys.c - pseudo-bus for system 'devices' (cpus, PICs, timers, etc)
4 * Copyright (c) 2002-3 Patrick Mochel
5 * 2002-3 Open Source Development Lab
7 * This file is released under the GPLv2
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.
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/string.h>
21 #include <linux/pm.h>
22 #include <linux/device.h>
23 #include <linux/mutex.h>
24 #include <linux/interrupt.h>
26 #include "base.h"
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)
32 static ssize_t
33 sysdev_show(struct kobject *kobj, struct attribute *attr, char *buffer)
35 struct sys_device *sysdev = to_sysdev(kobj);
36 struct sysdev_attribute *sysdev_attr = to_sysdev_attr(attr);
38 if (sysdev_attr->show)
39 return sysdev_attr->show(sysdev, sysdev_attr, buffer);
40 return -EIO;
44 static ssize_t
45 sysdev_store(struct kobject *kobj, struct attribute *attr,
46 const char *buffer, size_t count)
48 struct sys_device *sysdev = to_sysdev(kobj);
49 struct sysdev_attribute *sysdev_attr = to_sysdev_attr(attr);
51 if (sysdev_attr->store)
52 return sysdev_attr->store(sysdev, sysdev_attr, buffer, count);
53 return -EIO;
56 static const struct sysfs_ops sysfs_ops = {
57 .show = sysdev_show,
58 .store = sysdev_store,
61 static struct kobj_type ktype_sysdev = {
62 .sysfs_ops = &sysfs_ops,
66 int sysdev_create_file(struct sys_device *s, struct sysdev_attribute *a)
68 return sysfs_create_file(&s->kobj, &a->attr);
72 void sysdev_remove_file(struct sys_device *s, struct sysdev_attribute *a)
74 sysfs_remove_file(&s->kobj, &a->attr);
77 EXPORT_SYMBOL_GPL(sysdev_create_file);
78 EXPORT_SYMBOL_GPL(sysdev_remove_file);
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)
84 static ssize_t sysdev_class_show(struct kobject *kobj, struct attribute *attr,
85 char *buffer)
87 struct sysdev_class *class = to_sysdev_class(kobj);
88 struct sysdev_class_attribute *class_attr = to_sysdev_class_attr(attr);
90 if (class_attr->show)
91 return class_attr->show(class, class_attr, buffer);
92 return -EIO;
95 static ssize_t sysdev_class_store(struct kobject *kobj, struct attribute *attr,
96 const char *buffer, size_t count)
98 struct sysdev_class *class = to_sysdev_class(kobj);
99 struct sysdev_class_attribute *class_attr = to_sysdev_class_attr(attr);
101 if (class_attr->store)
102 return class_attr->store(class, class_attr, buffer, count);
103 return -EIO;
106 static const struct sysfs_ops sysfs_class_ops = {
107 .show = sysdev_class_show,
108 .store = sysdev_class_store,
111 static struct kobj_type ktype_sysdev_class = {
112 .sysfs_ops = &sysfs_class_ops,
115 int sysdev_class_create_file(struct sysdev_class *c,
116 struct sysdev_class_attribute *a)
118 return sysfs_create_file(&c->kset.kobj, &a->attr);
120 EXPORT_SYMBOL_GPL(sysdev_class_create_file);
122 void sysdev_class_remove_file(struct sysdev_class *c,
123 struct sysdev_class_attribute *a)
125 sysfs_remove_file(&c->kset.kobj, &a->attr);
127 EXPORT_SYMBOL_GPL(sysdev_class_remove_file);
129 static struct kset *system_kset;
131 int sysdev_class_register(struct sysdev_class *cls)
133 int retval;
135 pr_debug("Registering sysdev class '%s'\n", cls->name);
137 INIT_LIST_HEAD(&cls->drivers);
138 memset(&cls->kset.kobj, 0x00, sizeof(struct kobject));
139 cls->kset.kobj.parent = &system_kset->kobj;
140 cls->kset.kobj.ktype = &ktype_sysdev_class;
141 cls->kset.kobj.kset = system_kset;
143 retval = kobject_set_name(&cls->kset.kobj, "%s", cls->name);
144 if (retval)
145 return retval;
147 retval = kset_register(&cls->kset);
148 if (!retval && cls->attrs)
149 retval = sysfs_create_files(&cls->kset.kobj,
150 (const struct attribute **)cls->attrs);
151 return retval;
154 void sysdev_class_unregister(struct sysdev_class *cls)
156 pr_debug("Unregistering sysdev class '%s'\n",
157 kobject_name(&cls->kset.kobj));
158 if (cls->attrs)
159 sysfs_remove_files(&cls->kset.kobj,
160 (const struct attribute **)cls->attrs);
161 kset_unregister(&cls->kset);
164 EXPORT_SYMBOL_GPL(sysdev_class_register);
165 EXPORT_SYMBOL_GPL(sysdev_class_unregister);
167 static DEFINE_MUTEX(sysdev_drivers_lock);
170 * sysdev_driver_register - Register auxillary driver
171 * @cls: Device class driver belongs to.
172 * @drv: Driver.
174 * @drv is inserted into @cls->drivers to be
175 * called on each operation on devices of that class. The refcount
176 * of @cls is incremented.
179 int sysdev_driver_register(struct sysdev_class *cls, struct sysdev_driver *drv)
181 int err = 0;
183 if (!cls) {
184 WARN(1, KERN_WARNING "sysdev: invalid class passed to "
185 "sysdev_driver_register!\n");
186 return -EINVAL;
189 /* Check whether this driver has already been added to a class. */
190 if (drv->entry.next && !list_empty(&drv->entry))
191 WARN(1, KERN_WARNING "sysdev: class %s: driver (%p) has already"
192 " been registered to a class, something is wrong, but "
193 "will forge on!\n", cls->name, drv);
195 mutex_lock(&sysdev_drivers_lock);
196 if (cls && kset_get(&cls->kset)) {
197 list_add_tail(&drv->entry, &cls->drivers);
199 /* If devices of this class already exist, tell the driver */
200 if (drv->add) {
201 struct sys_device *dev;
202 list_for_each_entry(dev, &cls->kset.list, kobj.entry)
203 drv->add(dev);
205 } else {
206 err = -EINVAL;
207 WARN(1, KERN_ERR "%s: invalid device class\n", __func__);
209 mutex_unlock(&sysdev_drivers_lock);
210 return err;
215 * sysdev_driver_unregister - Remove an auxillary driver.
216 * @cls: Class driver belongs to.
217 * @drv: Driver.
219 void sysdev_driver_unregister(struct sysdev_class *cls,
220 struct sysdev_driver *drv)
222 mutex_lock(&sysdev_drivers_lock);
223 list_del_init(&drv->entry);
224 if (cls) {
225 if (drv->remove) {
226 struct sys_device *dev;
227 list_for_each_entry(dev, &cls->kset.list, kobj.entry)
228 drv->remove(dev);
230 kset_put(&cls->kset);
232 mutex_unlock(&sysdev_drivers_lock);
235 EXPORT_SYMBOL_GPL(sysdev_driver_register);
236 EXPORT_SYMBOL_GPL(sysdev_driver_unregister);
241 * sysdev_register - add a system device to the tree
242 * @sysdev: device in question
245 int sysdev_register(struct sys_device *sysdev)
247 int error;
248 struct sysdev_class *cls = sysdev->cls;
250 if (!cls)
251 return -EINVAL;
253 pr_debug("Registering sys device of class '%s'\n",
254 kobject_name(&cls->kset.kobj));
256 /* initialize the kobject to 0, in case it had previously been used */
257 memset(&sysdev->kobj, 0x00, sizeof(struct kobject));
259 /* Make sure the kset is set */
260 sysdev->kobj.kset = &cls->kset;
262 /* Register the object */
263 error = kobject_init_and_add(&sysdev->kobj, &ktype_sysdev, NULL,
264 "%s%d", kobject_name(&cls->kset.kobj),
265 sysdev->id);
267 if (!error) {
268 struct sysdev_driver *drv;
270 pr_debug("Registering sys device '%s'\n",
271 kobject_name(&sysdev->kobj));
273 mutex_lock(&sysdev_drivers_lock);
274 /* Generic notification is implicit, because it's that
275 * code that should have called us.
278 /* Notify class auxillary drivers */
279 list_for_each_entry(drv, &cls->drivers, entry) {
280 if (drv->add)
281 drv->add(sysdev);
283 mutex_unlock(&sysdev_drivers_lock);
284 kobject_uevent(&sysdev->kobj, KOBJ_ADD);
287 return error;
290 void sysdev_unregister(struct sys_device *sysdev)
292 struct sysdev_driver *drv;
294 mutex_lock(&sysdev_drivers_lock);
295 list_for_each_entry(drv, &sysdev->cls->drivers, entry) {
296 if (drv->remove)
297 drv->remove(sysdev);
299 mutex_unlock(&sysdev_drivers_lock);
301 kobject_put(&sysdev->kobj);
307 * sysdev_shutdown - Shut down all system devices.
309 * Loop over each class of system devices, and the devices in each
310 * of those classes. For each device, we call the shutdown method for
311 * each driver registered for the device - the auxillaries,
312 * and the class driver.
314 * Note: The list is iterated in reverse order, so that we shut down
315 * child devices before we shut down their parents. The list ordering
316 * is guaranteed by virtue of the fact that child devices are registered
317 * after their parents.
319 void sysdev_shutdown(void)
321 struct sysdev_class *cls;
323 pr_debug("Shutting Down System Devices\n");
325 mutex_lock(&sysdev_drivers_lock);
326 list_for_each_entry_reverse(cls, &system_kset->list, kset.kobj.entry) {
327 struct sys_device *sysdev;
329 pr_debug("Shutting down type '%s':\n",
330 kobject_name(&cls->kset.kobj));
332 list_for_each_entry(sysdev, &cls->kset.list, kobj.entry) {
333 struct sysdev_driver *drv;
334 pr_debug(" %s\n", kobject_name(&sysdev->kobj));
336 /* Call auxillary drivers first */
337 list_for_each_entry(drv, &cls->drivers, entry) {
338 if (drv->shutdown)
339 drv->shutdown(sysdev);
342 /* Now call the generic one */
343 if (cls->shutdown)
344 cls->shutdown(sysdev);
347 mutex_unlock(&sysdev_drivers_lock);
350 static void __sysdev_resume(struct sys_device *dev)
352 struct sysdev_class *cls = dev->cls;
353 struct sysdev_driver *drv;
355 /* First, call the class-specific one */
356 if (cls->resume)
357 cls->resume(dev);
358 WARN_ONCE(!irqs_disabled(),
359 "Interrupts enabled after %pF\n", cls->resume);
361 /* Call auxillary drivers next. */
362 list_for_each_entry(drv, &cls->drivers, entry) {
363 if (drv->resume)
364 drv->resume(dev);
365 WARN_ONCE(!irqs_disabled(),
366 "Interrupts enabled after %pF\n", drv->resume);
371 * sysdev_suspend - Suspend all system devices.
372 * @state: Power state to enter.
374 * We perform an almost identical operation as sysdev_shutdown()
375 * above, though calling ->suspend() instead. Interrupts are disabled
376 * when this called. Devices are responsible for both saving state and
377 * quiescing or powering down the device.
379 * This is only called by the device PM core, so we let them handle
380 * all synchronization.
382 int sysdev_suspend(pm_message_t state)
384 struct sysdev_class *cls;
385 struct sys_device *sysdev, *err_dev;
386 struct sysdev_driver *drv, *err_drv;
387 int ret;
389 pr_debug("Checking wake-up interrupts\n");
391 /* Return error code if there are any wake-up interrupts pending */
392 ret = check_wakeup_irqs();
393 if (ret)
394 return ret;
396 WARN_ONCE(!irqs_disabled(),
397 "Interrupts enabled while suspending system devices\n");
399 pr_debug("Suspending System Devices\n");
401 list_for_each_entry_reverse(cls, &system_kset->list, kset.kobj.entry) {
402 pr_debug("Suspending type '%s':\n",
403 kobject_name(&cls->kset.kobj));
405 list_for_each_entry(sysdev, &cls->kset.list, kobj.entry) {
406 pr_debug(" %s\n", kobject_name(&sysdev->kobj));
408 /* Call auxillary drivers first */
409 list_for_each_entry(drv, &cls->drivers, entry) {
410 if (drv->suspend) {
411 ret = drv->suspend(sysdev, state);
412 if (ret)
413 goto aux_driver;
415 WARN_ONCE(!irqs_disabled(),
416 "Interrupts enabled after %pF\n",
417 drv->suspend);
420 /* Now call the generic one */
421 if (cls->suspend) {
422 ret = cls->suspend(sysdev, state);
423 if (ret)
424 goto cls_driver;
425 WARN_ONCE(!irqs_disabled(),
426 "Interrupts enabled after %pF\n",
427 cls->suspend);
431 return 0;
432 /* resume current sysdev */
433 cls_driver:
434 drv = NULL;
435 printk(KERN_ERR "Class suspend failed for %s\n",
436 kobject_name(&sysdev->kobj));
438 aux_driver:
439 if (drv)
440 printk(KERN_ERR "Class driver suspend failed for %s\n",
441 kobject_name(&sysdev->kobj));
442 list_for_each_entry(err_drv, &cls->drivers, entry) {
443 if (err_drv == drv)
444 break;
445 if (err_drv->resume)
446 err_drv->resume(sysdev);
449 /* resume other sysdevs in current class */
450 list_for_each_entry(err_dev, &cls->kset.list, kobj.entry) {
451 if (err_dev == sysdev)
452 break;
453 pr_debug(" %s\n", kobject_name(&err_dev->kobj));
454 __sysdev_resume(err_dev);
457 /* resume other classes */
458 list_for_each_entry_continue(cls, &system_kset->list, kset.kobj.entry) {
459 list_for_each_entry(err_dev, &cls->kset.list, kobj.entry) {
460 pr_debug(" %s\n", kobject_name(&err_dev->kobj));
461 __sysdev_resume(err_dev);
464 return ret;
466 EXPORT_SYMBOL_GPL(sysdev_suspend);
469 * sysdev_resume - Bring system devices back to life.
471 * Similar to sysdev_suspend(), but we iterate the list forwards
472 * to guarantee that parent devices are resumed before their children.
474 * Note: Interrupts are disabled when called.
476 int sysdev_resume(void)
478 struct sysdev_class *cls;
480 WARN_ONCE(!irqs_disabled(),
481 "Interrupts enabled while resuming system devices\n");
483 pr_debug("Resuming System Devices\n");
485 list_for_each_entry(cls, &system_kset->list, kset.kobj.entry) {
486 struct sys_device *sysdev;
488 pr_debug("Resuming type '%s':\n",
489 kobject_name(&cls->kset.kobj));
491 list_for_each_entry(sysdev, &cls->kset.list, kobj.entry) {
492 pr_debug(" %s\n", kobject_name(&sysdev->kobj));
494 __sysdev_resume(sysdev);
497 return 0;
499 EXPORT_SYMBOL_GPL(sysdev_resume);
501 int __init system_bus_init(void)
503 system_kset = kset_create_and_add("system", NULL, &devices_kset->kobj);
504 if (!system_kset)
505 return -ENOMEM;
506 return 0;
509 EXPORT_SYMBOL_GPL(sysdev_register);
510 EXPORT_SYMBOL_GPL(sysdev_unregister);
512 #define to_ext_attr(x) container_of(x, struct sysdev_ext_attribute, attr)
514 ssize_t sysdev_store_ulong(struct sys_device *sysdev,
515 struct sysdev_attribute *attr,
516 const char *buf, size_t size)
518 struct sysdev_ext_attribute *ea = to_ext_attr(attr);
519 char *end;
520 unsigned long new = simple_strtoul(buf, &end, 0);
521 if (end == buf)
522 return -EINVAL;
523 *(unsigned long *)(ea->var) = new;
524 /* Always return full write size even if we didn't consume all */
525 return size;
527 EXPORT_SYMBOL_GPL(sysdev_store_ulong);
529 ssize_t sysdev_show_ulong(struct sys_device *sysdev,
530 struct sysdev_attribute *attr,
531 char *buf)
533 struct sysdev_ext_attribute *ea = to_ext_attr(attr);
534 return snprintf(buf, PAGE_SIZE, "%lx\n", *(unsigned long *)(ea->var));
536 EXPORT_SYMBOL_GPL(sysdev_show_ulong);
538 ssize_t sysdev_store_int(struct sys_device *sysdev,
539 struct sysdev_attribute *attr,
540 const char *buf, size_t size)
542 struct sysdev_ext_attribute *ea = to_ext_attr(attr);
543 char *end;
544 long new = simple_strtol(buf, &end, 0);
545 if (end == buf || new > INT_MAX || new < INT_MIN)
546 return -EINVAL;
547 *(int *)(ea->var) = new;
548 /* Always return full write size even if we didn't consume all */
549 return size;
551 EXPORT_SYMBOL_GPL(sysdev_store_int);
553 ssize_t sysdev_show_int(struct sys_device *sysdev,
554 struct sysdev_attribute *attr,
555 char *buf)
557 struct sysdev_ext_attribute *ea = to_ext_attr(attr);
558 return snprintf(buf, PAGE_SIZE, "%d\n", *(int *)(ea->var));
560 EXPORT_SYMBOL_GPL(sysdev_show_int);