2 * drivers/base/core.c - core driver model code (device registration, etc)
4 * Copyright (c) 2002-3 Patrick Mochel
5 * Copyright (c) 2002-3 Open Source Development Labs
6 * Copyright (c) 2006 Greg Kroah-Hartman <gregkh@suse.de>
7 * Copyright (c) 2006 Novell, Inc.
9 * This file is released under the GPLv2
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>
19 #include <linux/kdev_t.h>
20 #include <linux/notifier.h>
22 #include <asm/semaphore.h>
25 #include "power/power.h"
27 int (*platform_notify)(struct device * dev) = NULL;
28 int (*platform_notify_remove)(struct device * dev) = NULL;
31 * sysfs bindings for devices.
35 * dev_driver_string - Return a device's driver name, if at all possible
36 * @dev: struct device to get the name of
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.
43 const char *dev_driver_string(struct device *dev)
45 return dev->driver ? dev->driver->name :
46 (dev->bus ? dev->bus->name :
47 (dev->class ? dev->class->name : ""));
49 EXPORT_SYMBOL(dev_driver_string);
51 #define to_dev(obj) container_of(obj, struct device, kobj)
52 #define to_dev_attr(_attr) container_of(_attr, struct device_attribute, attr)
55 dev_attr_show(struct kobject * kobj, struct attribute * attr, char * buf)
57 struct device_attribute * dev_attr = to_dev_attr(attr);
58 struct device * dev = to_dev(kobj);
62 ret = dev_attr->show(dev, dev_attr, buf);
67 dev_attr_store(struct kobject * kobj, struct attribute * attr,
68 const char * buf, size_t count)
70 struct device_attribute * dev_attr = to_dev_attr(attr);
71 struct device * dev = to_dev(kobj);
75 ret = dev_attr->store(dev, dev_attr, buf, count);
79 static struct sysfs_ops dev_sysfs_ops = {
80 .show = dev_attr_show,
81 .store = dev_attr_store,
86 * device_release - free device structure.
87 * @kobj: device's kobject.
89 * This is called once the reference count for the object
90 * reaches 0. We forward the call to the device's release
91 * method, which should handle actually freeing the structure.
93 static void device_release(struct kobject * kobj)
95 struct device * dev = to_dev(kobj);
99 else if (dev->type && dev->type->release)
100 dev->type->release(dev);
101 else if (dev->class && dev->class->dev_release)
102 dev->class->dev_release(dev);
104 printk(KERN_ERR "Device '%s' does not have a release() function, "
105 "it is broken and must be fixed.\n",
111 static struct kobj_type ktype_device = {
112 .release = device_release,
113 .sysfs_ops = &dev_sysfs_ops,
117 static int dev_uevent_filter(struct kset *kset, struct kobject *kobj)
119 struct kobj_type *ktype = get_ktype(kobj);
121 if (ktype == &ktype_device) {
122 struct device *dev = to_dev(kobj);
123 if (dev->uevent_suppress)
133 static const char *dev_uevent_name(struct kset *kset, struct kobject *kobj)
135 struct device *dev = to_dev(kobj);
138 return dev->bus->name;
140 return dev->class->name;
144 static int dev_uevent(struct kset *kset, struct kobject *kobj, char **envp,
145 int num_envp, char *buffer, int buffer_size)
147 struct device *dev = to_dev(kobj);
152 /* add the major/minor if present */
153 if (MAJOR(dev->devt)) {
154 add_uevent_var(envp, num_envp, &i,
155 buffer, buffer_size, &length,
156 "MAJOR=%u", MAJOR(dev->devt));
157 add_uevent_var(envp, num_envp, &i,
158 buffer, buffer_size, &length,
159 "MINOR=%u", MINOR(dev->devt));
162 if (dev->type && dev->type->name)
163 add_uevent_var(envp, num_envp, &i,
164 buffer, buffer_size, &length,
165 "DEVTYPE=%s", dev->type->name);
168 add_uevent_var(envp, num_envp, &i,
169 buffer, buffer_size, &length,
170 "DRIVER=%s", dev->driver->name);
172 #ifdef CONFIG_SYSFS_DEPRECATED
174 struct device *parent = dev->parent;
176 /* find first bus device in parent chain */
177 while (parent && !parent->bus)
178 parent = parent->parent;
179 if (parent && parent->bus) {
182 path = kobject_get_path(&parent->kobj, GFP_KERNEL);
183 add_uevent_var(envp, num_envp, &i,
184 buffer, buffer_size, &length,
185 "PHYSDEVPATH=%s", path);
188 add_uevent_var(envp, num_envp, &i,
189 buffer, buffer_size, &length,
190 "PHYSDEVBUS=%s", parent->bus->name);
193 add_uevent_var(envp, num_envp, &i,
194 buffer, buffer_size, &length,
195 "PHYSDEVDRIVER=%s", parent->driver->name);
197 } else if (dev->bus) {
198 add_uevent_var(envp, num_envp, &i,
199 buffer, buffer_size, &length,
200 "PHYSDEVBUS=%s", dev->bus->name);
203 add_uevent_var(envp, num_envp, &i,
204 buffer, buffer_size, &length,
205 "PHYSDEVDRIVER=%s", dev->driver->name);
209 /* terminate, set to next free slot, shrink available space */
213 buffer = &buffer[length];
214 buffer_size -= length;
216 if (dev->bus && dev->bus->uevent) {
217 /* have the bus specific function add its stuff */
218 retval = dev->bus->uevent(dev, envp, num_envp, buffer, buffer_size);
220 pr_debug ("%s: bus uevent() returned %d\n",
221 __FUNCTION__, retval);
224 if (dev->class && dev->class->dev_uevent) {
225 /* have the class specific function add its stuff */
226 retval = dev->class->dev_uevent(dev, envp, num_envp, buffer, buffer_size);
228 pr_debug("%s: class uevent() returned %d\n",
229 __FUNCTION__, retval);
232 if (dev->type && dev->type->uevent) {
233 /* have the device type specific fuction add its stuff */
234 retval = dev->type->uevent(dev, envp, num_envp, buffer, buffer_size);
236 pr_debug("%s: dev_type uevent() returned %d\n",
237 __FUNCTION__, retval);
243 static struct kset_uevent_ops device_uevent_ops = {
244 .filter = dev_uevent_filter,
245 .name = dev_uevent_name,
246 .uevent = dev_uevent,
249 static ssize_t show_uevent(struct device *dev, struct device_attribute *attr,
252 struct kobject *top_kobj;
255 char data[PAGE_SIZE];
261 /* search the kset, the device belongs to */
262 top_kobj = &dev->kobj;
263 if (!top_kobj->kset && top_kobj->parent) {
265 top_kobj = top_kobj->parent;
266 } while (!top_kobj->kset && top_kobj->parent);
270 kset = top_kobj->kset;
271 if (!kset->uevent_ops || !kset->uevent_ops->uevent)
275 if (kset->uevent_ops && kset->uevent_ops->filter)
276 if (!kset->uevent_ops->filter(kset, &dev->kobj))
279 /* let the kset specific function add its keys */
281 retval = kset->uevent_ops->uevent(kset, &dev->kobj,
282 envp, ARRAY_SIZE(envp),
287 /* copy keys to file */
288 for (i = 0; envp[i]; i++) {
290 count += sprintf(pos, "%s\n", envp[i]);
296 static ssize_t store_uevent(struct device *dev, struct device_attribute *attr,
297 const char *buf, size_t count)
299 kobject_uevent(&dev->kobj, KOBJ_ADD);
303 static int device_add_attributes(struct device *dev,
304 struct device_attribute *attrs)
310 for (i = 0; attr_name(attrs[i]); i++) {
311 error = device_create_file(dev, &attrs[i]);
317 device_remove_file(dev, &attrs[i]);
322 static void device_remove_attributes(struct device *dev,
323 struct device_attribute *attrs)
328 for (i = 0; attr_name(attrs[i]); i++)
329 device_remove_file(dev, &attrs[i]);
332 static int device_add_groups(struct device *dev,
333 struct attribute_group **groups)
339 for (i = 0; groups[i]; i++) {
340 error = sysfs_create_group(&dev->kobj, groups[i]);
343 sysfs_remove_group(&dev->kobj, groups[i]);
351 static void device_remove_groups(struct device *dev,
352 struct attribute_group **groups)
357 for (i = 0; groups[i]; i++)
358 sysfs_remove_group(&dev->kobj, groups[i]);
361 static int device_add_attrs(struct device *dev)
363 struct class *class = dev->class;
364 struct device_type *type = dev->type;
368 error = device_add_attributes(dev, class->dev_attrs);
374 error = device_add_groups(dev, type->groups);
376 goto err_remove_class_attrs;
379 error = device_add_groups(dev, dev->groups);
381 goto err_remove_type_groups;
385 err_remove_type_groups:
387 device_remove_groups(dev, type->groups);
388 err_remove_class_attrs:
390 device_remove_attributes(dev, class->dev_attrs);
395 static void device_remove_attrs(struct device *dev)
397 struct class *class = dev->class;
398 struct device_type *type = dev->type;
400 device_remove_groups(dev, dev->groups);
403 device_remove_groups(dev, type->groups);
406 device_remove_attributes(dev, class->dev_attrs);
410 static ssize_t show_dev(struct device *dev, struct device_attribute *attr,
413 return print_dev_t(buf, dev->devt);
417 * devices_subsys - structure to be registered with kobject core.
420 decl_subsys(devices, &ktype_device, &device_uevent_ops);
424 * device_create_file - create sysfs attribute file for device.
426 * @attr: device attribute descriptor.
429 int device_create_file(struct device * dev, struct device_attribute * attr)
432 if (get_device(dev)) {
433 error = sysfs_create_file(&dev->kobj, &attr->attr);
440 * device_remove_file - remove sysfs attribute file.
442 * @attr: device attribute descriptor.
445 void device_remove_file(struct device * dev, struct device_attribute * attr)
447 if (get_device(dev)) {
448 sysfs_remove_file(&dev->kobj, &attr->attr);
454 * device_create_bin_file - create sysfs binary attribute file for device.
456 * @attr: device binary attribute descriptor.
458 int device_create_bin_file(struct device *dev, struct bin_attribute *attr)
462 error = sysfs_create_bin_file(&dev->kobj, attr);
465 EXPORT_SYMBOL_GPL(device_create_bin_file);
468 * device_remove_bin_file - remove sysfs binary attribute file
470 * @attr: device binary attribute descriptor.
472 void device_remove_bin_file(struct device *dev, struct bin_attribute *attr)
475 sysfs_remove_bin_file(&dev->kobj, attr);
477 EXPORT_SYMBOL_GPL(device_remove_bin_file);
480 * device_schedule_callback - helper to schedule a callback for a device
482 * @func: callback function to invoke later.
484 * Attribute methods must not unregister themselves or their parent device
485 * (which would amount to the same thing). Attempts to do so will deadlock,
486 * since unregistration is mutually exclusive with driver callbacks.
488 * Instead methods can call this routine, which will attempt to allocate
489 * and schedule a workqueue request to call back @func with @dev as its
490 * argument in the workqueue's process context. @dev will be pinned until
493 * Returns 0 if the request was submitted, -ENOMEM if storage could not
496 * NOTE: This routine won't work if CONFIG_SYSFS isn't set! It uses an
497 * underlying sysfs routine (since it is intended for use by attribute
498 * methods), and if sysfs isn't available you'll get nothing but -ENOSYS.
500 int device_schedule_callback(struct device *dev,
501 void (*func)(struct device *))
503 return sysfs_schedule_callback(&dev->kobj,
504 (void (*)(void *)) func, dev);
506 EXPORT_SYMBOL_GPL(device_schedule_callback);
508 static void klist_children_get(struct klist_node *n)
510 struct device *dev = container_of(n, struct device, knode_parent);
515 static void klist_children_put(struct klist_node *n)
517 struct device *dev = container_of(n, struct device, knode_parent);
524 * device_initialize - init device structure.
527 * This prepares the device for use by other layers,
528 * including adding it to the device hierarchy.
529 * It is the first half of device_register(), if called by
530 * that, though it can also be called separately, so one
531 * may use @dev's fields (e.g. the refcount).
534 void device_initialize(struct device *dev)
536 kobj_set_kset_s(dev, devices_subsys);
537 kobject_init(&dev->kobj);
538 klist_init(&dev->klist_children, klist_children_get,
540 INIT_LIST_HEAD(&dev->dma_pools);
541 INIT_LIST_HEAD(&dev->node);
542 init_MUTEX(&dev->sem);
543 spin_lock_init(&dev->devres_lock);
544 INIT_LIST_HEAD(&dev->devres_head);
545 device_init_wakeup(dev, 0);
546 set_dev_node(dev, -1);
549 #ifdef CONFIG_SYSFS_DEPRECATED
550 static struct kobject * get_device_parent(struct device *dev,
551 struct device *parent)
553 /* Set the parent to the class, not the parent device */
554 /* this keeps sysfs from having a symlink to make old udevs happy */
556 return &dev->class->subsys.kset.kobj;
558 return &parent->kobj;
563 static struct kobject *virtual_device_parent(struct device *dev)
565 static struct kobject *virtual_dir = NULL;
568 virtual_dir = kobject_add_dir(&devices_subsys.kset.kobj, "virtual");
573 static struct kobject * get_device_parent(struct device *dev,
574 struct device *parent)
577 struct kobject *kobj = NULL;
578 struct kobject *parent_kobj;
582 * If we have no parent, we live in "virtual".
583 * Class-devices with a bus-device as parent, live
584 * in a class-directory to prevent namespace collisions.
587 parent_kobj = virtual_device_parent(dev);
588 else if (parent->class)
589 return &parent->kobj;
591 parent_kobj = &parent->kobj;
593 /* find our class-directory at the parent and reference it */
594 spin_lock(&dev->class->class_dirs.list_lock);
595 list_for_each_entry(k, &dev->class->class_dirs.list, entry)
596 if (k->parent == parent_kobj) {
597 kobj = kobject_get(k);
600 spin_unlock(&dev->class->class_dirs.list_lock);
604 /* or create a new class-directory at the parent device */
605 return kobject_kset_add_dir(&dev->class->class_dirs,
606 parent_kobj, dev->class->name);
610 return &parent->kobj;
615 static int setup_parent(struct device *dev, struct device *parent)
617 struct kobject *kobj;
618 kobj = get_device_parent(dev, parent);
620 return PTR_ERR(kobj);
622 dev->kobj.parent = kobj;
627 * device_add - add device to device hierarchy.
630 * This is part 2 of device_register(), though may be called
631 * separately _iff_ device_initialize() has been called separately.
633 * This adds it to the kobject hierarchy via kobject_add(), adds it
634 * to the global and sibling lists for the device, then
635 * adds it to the other relevant subsystems of the driver model.
637 int device_add(struct device *dev)
639 struct device *parent = NULL;
640 char *class_name = NULL;
641 struct class_interface *class_intf;
644 dev = get_device(dev);
645 if (!dev || !strlen(dev->bus_id))
648 pr_debug("DEV: registering device: ID = '%s'\n", dev->bus_id);
650 parent = get_device(dev->parent);
651 error = setup_parent(dev, parent);
655 /* first, register with generic layer. */
656 kobject_set_name(&dev->kobj, "%s", dev->bus_id);
657 error = kobject_add(&dev->kobj);
661 /* notify platform of device entry */
663 platform_notify(dev);
665 /* notify clients of device entry (new way) */
667 blocking_notifier_call_chain(&dev->bus->bus_notifier,
668 BUS_NOTIFY_ADD_DEVICE, dev);
670 dev->uevent_attr.attr.name = "uevent";
671 dev->uevent_attr.attr.mode = S_IRUGO | S_IWUSR;
673 dev->uevent_attr.attr.owner = dev->driver->owner;
674 dev->uevent_attr.store = store_uevent;
675 dev->uevent_attr.show = show_uevent;
676 error = device_create_file(dev, &dev->uevent_attr);
680 if (MAJOR(dev->devt)) {
681 struct device_attribute *attr;
682 attr = kzalloc(sizeof(*attr), GFP_KERNEL);
685 goto ueventattrError;
687 attr->attr.name = "dev";
688 attr->attr.mode = S_IRUGO;
690 attr->attr.owner = dev->driver->owner;
691 attr->show = show_dev;
692 error = device_create_file(dev, attr);
695 goto ueventattrError;
698 dev->devt_attr = attr;
702 sysfs_create_link(&dev->kobj, &dev->class->subsys.kset.kobj,
704 /* If this is not a "fake" compatible device, then create the
705 * symlink from the class to the device. */
706 if (dev->kobj.parent != &dev->class->subsys.kset.kobj)
707 sysfs_create_link(&dev->class->subsys.kset.kobj,
708 &dev->kobj, dev->bus_id);
710 sysfs_create_link(&dev->kobj, &dev->parent->kobj,
712 #ifdef CONFIG_SYSFS_DEPRECATED
713 class_name = make_class_name(dev->class->name,
716 sysfs_create_link(&dev->parent->kobj,
717 &dev->kobj, class_name);
722 if ((error = device_add_attrs(dev)))
724 if ((error = device_pm_add(dev)))
726 if ((error = bus_add_device(dev)))
728 kobject_uevent(&dev->kobj, KOBJ_ADD);
729 bus_attach_device(dev);
731 klist_add_tail(&dev->knode_parent, &parent->klist_children);
734 down(&dev->class->sem);
735 /* tie the class to the device */
736 list_add_tail(&dev->node, &dev->class->devices);
738 /* notify any interfaces that the device is here */
739 list_for_each_entry(class_intf, &dev->class->interfaces, node)
740 if (class_intf->add_dev)
741 class_intf->add_dev(dev, class_intf);
742 up(&dev->class->sem);
749 device_pm_remove(dev);
752 blocking_notifier_call_chain(&dev->bus->bus_notifier,
753 BUS_NOTIFY_DEL_DEVICE, dev);
754 device_remove_attrs(dev);
756 if (dev->devt_attr) {
757 device_remove_file(dev, dev->devt_attr);
758 kfree(dev->devt_attr);
762 sysfs_remove_link(&dev->kobj, "subsystem");
763 /* If this is not a "fake" compatible device, remove the
764 * symlink from the class to the device. */
765 if (dev->kobj.parent != &dev->class->subsys.kset.kobj)
766 sysfs_remove_link(&dev->class->subsys.kset.kobj,
769 #ifdef CONFIG_SYSFS_DEPRECATED
770 char *class_name = make_class_name(dev->class->name,
773 sysfs_remove_link(&dev->parent->kobj,
777 sysfs_remove_link(&dev->kobj, "device");
781 device_remove_file(dev, &dev->uevent_attr);
783 kobject_uevent(&dev->kobj, KOBJ_REMOVE);
784 kobject_del(&dev->kobj);
793 * device_register - register a device with the system.
794 * @dev: pointer to the device structure
796 * This happens in two clean steps - initialize the device
797 * and add it to the system. The two steps can be called
798 * separately, but this is the easiest and most common.
799 * I.e. you should only call the two helpers separately if
800 * have a clearly defined need to use and refcount the device
801 * before it is added to the hierarchy.
804 int device_register(struct device *dev)
806 device_initialize(dev);
807 return device_add(dev);
812 * get_device - increment reference count for device.
815 * This simply forwards the call to kobject_get(), though
816 * we do take care to provide for the case that we get a NULL
820 struct device * get_device(struct device * dev)
822 return dev ? to_dev(kobject_get(&dev->kobj)) : NULL;
827 * put_device - decrement reference count.
828 * @dev: device in question.
830 void put_device(struct device * dev)
833 kobject_put(&dev->kobj);
838 * device_del - delete device from system.
841 * This is the first part of the device unregistration
842 * sequence. This removes the device from the lists we control
843 * from here, has it removed from the other driver model
844 * subsystems it was added to in device_add(), and removes it
845 * from the kobject hierarchy.
847 * NOTE: this should be called manually _iff_ device_add() was
848 * also called manually.
851 void device_del(struct device * dev)
853 struct device * parent = dev->parent;
854 struct class_interface *class_intf;
857 klist_del(&dev->knode_parent);
858 if (dev->devt_attr) {
859 device_remove_file(dev, dev->devt_attr);
860 kfree(dev->devt_attr);
863 sysfs_remove_link(&dev->kobj, "subsystem");
864 /* If this is not a "fake" compatible device, remove the
865 * symlink from the class to the device. */
866 if (dev->kobj.parent != &dev->class->subsys.kset.kobj)
867 sysfs_remove_link(&dev->class->subsys.kset.kobj,
870 #ifdef CONFIG_SYSFS_DEPRECATED
871 char *class_name = make_class_name(dev->class->name,
874 sysfs_remove_link(&dev->parent->kobj,
878 sysfs_remove_link(&dev->kobj, "device");
881 down(&dev->class->sem);
882 /* notify any interfaces that the device is now gone */
883 list_for_each_entry(class_intf, &dev->class->interfaces, node)
884 if (class_intf->remove_dev)
885 class_intf->remove_dev(dev, class_intf);
886 /* remove the device from the class list */
887 list_del_init(&dev->node);
888 up(&dev->class->sem);
890 /* If we live in a parent class-directory, unreference it */
891 if (dev->kobj.parent->kset == &dev->class->class_dirs) {
896 * if we are the last child of our class, delete
897 * our class-directory at this parent
899 down(&dev->class->sem);
900 list_for_each_entry(d, &dev->class->devices, node) {
903 if (d->kobj.parent == dev->kobj.parent) {
909 kobject_del(dev->kobj.parent);
911 kobject_put(dev->kobj.parent);
912 up(&dev->class->sem);
915 device_remove_file(dev, &dev->uevent_attr);
916 device_remove_attrs(dev);
917 bus_remove_device(dev);
920 * Some platform devices are driven without driver attached
921 * and managed resources may have been acquired. Make sure
922 * all resources are released.
924 devres_release_all(dev);
926 /* Notify the platform of the removal, in case they
927 * need to do anything...
929 if (platform_notify_remove)
930 platform_notify_remove(dev);
932 blocking_notifier_call_chain(&dev->bus->bus_notifier,
933 BUS_NOTIFY_DEL_DEVICE, dev);
934 device_pm_remove(dev);
935 kobject_uevent(&dev->kobj, KOBJ_REMOVE);
936 kobject_del(&dev->kobj);
942 * device_unregister - unregister device from system.
943 * @dev: device going away.
945 * We do this in two parts, like we do device_register(). First,
946 * we remove it from all the subsystems with device_del(), then
947 * we decrement the reference count via put_device(). If that
948 * is the final reference count, the device will be cleaned up
949 * via device_release() above. Otherwise, the structure will
950 * stick around until the final reference to the device is dropped.
952 void device_unregister(struct device * dev)
954 pr_debug("DEV: Unregistering device. ID = '%s'\n", dev->bus_id);
960 static struct device * next_device(struct klist_iter * i)
962 struct klist_node * n = klist_next(i);
963 return n ? container_of(n, struct device, knode_parent) : NULL;
967 * device_for_each_child - device child iterator.
968 * @parent: parent struct device.
969 * @data: data for the callback.
970 * @fn: function to be called for each device.
972 * Iterate over @parent's child devices, and call @fn for each,
975 * We check the return of @fn each time. If it returns anything
976 * other than 0, we break out and return that value.
978 int device_for_each_child(struct device * parent, void * data,
979 int (*fn)(struct device *, void *))
982 struct device * child;
985 klist_iter_init(&parent->klist_children, &i);
986 while ((child = next_device(&i)) && !error)
987 error = fn(child, data);
993 * device_find_child - device iterator for locating a particular device.
994 * @parent: parent struct device
995 * @data: Data to pass to match function
996 * @match: Callback function to check device
998 * This is similar to the device_for_each_child() function above, but it
999 * returns a reference to a device that is 'found' for later use, as
1000 * determined by the @match callback.
1002 * The callback should return 0 if the device doesn't match and non-zero
1003 * if it does. If the callback returns non-zero and a reference to the
1004 * current device can be obtained, this function will return to the caller
1005 * and not iterate over any more devices.
1007 struct device * device_find_child(struct device *parent, void *data,
1008 int (*match)(struct device *, void *))
1010 struct klist_iter i;
1011 struct device *child;
1016 klist_iter_init(&parent->klist_children, &i);
1017 while ((child = next_device(&i)))
1018 if (match(child, data) && get_device(child))
1020 klist_iter_exit(&i);
1024 int __init devices_init(void)
1026 return subsystem_register(&devices_subsys);
1029 EXPORT_SYMBOL_GPL(device_for_each_child);
1030 EXPORT_SYMBOL_GPL(device_find_child);
1032 EXPORT_SYMBOL_GPL(device_initialize);
1033 EXPORT_SYMBOL_GPL(device_add);
1034 EXPORT_SYMBOL_GPL(device_register);
1036 EXPORT_SYMBOL_GPL(device_del);
1037 EXPORT_SYMBOL_GPL(device_unregister);
1038 EXPORT_SYMBOL_GPL(get_device);
1039 EXPORT_SYMBOL_GPL(put_device);
1041 EXPORT_SYMBOL_GPL(device_create_file);
1042 EXPORT_SYMBOL_GPL(device_remove_file);
1045 static void device_create_release(struct device *dev)
1047 pr_debug("%s called for %s\n", __FUNCTION__, dev->bus_id);
1052 * device_create - creates a device and registers it with sysfs
1053 * @class: pointer to the struct class that this device should be registered to
1054 * @parent: pointer to the parent struct device of this new device, if any
1055 * @devt: the dev_t for the char device to be added
1056 * @fmt: string for the device's name
1058 * This function can be used by char device classes. A struct device
1059 * will be created in sysfs, registered to the specified class.
1061 * A "dev" file will be created, showing the dev_t for the device, if
1062 * the dev_t is not 0,0.
1063 * If a pointer to a parent struct device is passed in, the newly created
1064 * struct device will be a child of that device in sysfs.
1065 * The pointer to the struct device will be returned from the call.
1066 * Any further sysfs files that might be required can be created using this
1069 * Note: the struct class passed to this function must have previously
1070 * been created with a call to class_create().
1072 struct device *device_create(struct class *class, struct device *parent,
1073 dev_t devt, const char *fmt, ...)
1076 struct device *dev = NULL;
1077 int retval = -ENODEV;
1079 if (class == NULL || IS_ERR(class))
1082 dev = kzalloc(sizeof(*dev), GFP_KERNEL);
1090 dev->parent = parent;
1091 dev->release = device_create_release;
1093 va_start(args, fmt);
1094 vsnprintf(dev->bus_id, BUS_ID_SIZE, fmt, args);
1096 retval = device_register(dev);
1104 return ERR_PTR(retval);
1106 EXPORT_SYMBOL_GPL(device_create);
1109 * device_destroy - removes a device that was created with device_create()
1110 * @class: pointer to the struct class that this device was registered with
1111 * @devt: the dev_t of the device that was previously registered
1113 * This call unregisters and cleans up a device that was created with a
1114 * call to device_create().
1116 void device_destroy(struct class *class, dev_t devt)
1118 struct device *dev = NULL;
1119 struct device *dev_tmp;
1122 list_for_each_entry(dev_tmp, &class->devices, node) {
1123 if (dev_tmp->devt == devt) {
1131 device_unregister(dev);
1133 EXPORT_SYMBOL_GPL(device_destroy);
1136 * device_rename - renames a device
1137 * @dev: the pointer to the struct device to be renamed
1138 * @new_name: the new name of the device
1140 int device_rename(struct device *dev, char *new_name)
1142 char *old_class_name = NULL;
1143 char *new_class_name = NULL;
1144 char *old_symlink_name = NULL;
1147 dev = get_device(dev);
1151 pr_debug("DEVICE: renaming '%s' to '%s'\n", dev->bus_id, new_name);
1153 #ifdef CONFIG_SYSFS_DEPRECATED
1154 if ((dev->class) && (dev->parent))
1155 old_class_name = make_class_name(dev->class->name, &dev->kobj);
1159 old_symlink_name = kmalloc(BUS_ID_SIZE, GFP_KERNEL);
1160 if (!old_symlink_name) {
1162 goto out_free_old_class;
1164 strlcpy(old_symlink_name, dev->bus_id, BUS_ID_SIZE);
1167 strlcpy(dev->bus_id, new_name, BUS_ID_SIZE);
1169 error = kobject_rename(&dev->kobj, new_name);
1171 #ifdef CONFIG_SYSFS_DEPRECATED
1172 if (old_class_name) {
1173 new_class_name = make_class_name(dev->class->name, &dev->kobj);
1174 if (new_class_name) {
1175 sysfs_create_link(&dev->parent->kobj, &dev->kobj,
1177 sysfs_remove_link(&dev->parent->kobj, old_class_name);
1183 sysfs_remove_link(&dev->class->subsys.kset.kobj,
1185 sysfs_create_link(&dev->class->subsys.kset.kobj, &dev->kobj,
1190 kfree(new_class_name);
1191 kfree(old_symlink_name);
1193 kfree(old_class_name);
1197 EXPORT_SYMBOL_GPL(device_rename);
1199 static int device_move_class_links(struct device *dev,
1200 struct device *old_parent,
1201 struct device *new_parent)
1204 #ifdef CONFIG_SYSFS_DEPRECATED
1207 class_name = make_class_name(dev->class->name, &dev->kobj);
1213 sysfs_remove_link(&dev->kobj, "device");
1214 sysfs_remove_link(&old_parent->kobj, class_name);
1217 error = sysfs_create_link(&dev->kobj, &new_parent->kobj,
1221 error = sysfs_create_link(&new_parent->kobj, &dev->kobj,
1224 sysfs_remove_link(&dev->kobj, "device");
1233 sysfs_remove_link(&dev->kobj, "device");
1235 error = sysfs_create_link(&dev->kobj, &new_parent->kobj,
1242 * device_move - moves a device to a new parent
1243 * @dev: the pointer to the struct device to be moved
1244 * @new_parent: the new parent of the device (can by NULL)
1246 int device_move(struct device *dev, struct device *new_parent)
1249 struct device *old_parent;
1250 struct kobject *new_parent_kobj;
1252 dev = get_device(dev);
1256 new_parent = get_device(new_parent);
1257 new_parent_kobj = get_device_parent (dev, new_parent);
1258 if (IS_ERR(new_parent_kobj)) {
1259 error = PTR_ERR(new_parent_kobj);
1260 put_device(new_parent);
1263 pr_debug("DEVICE: moving '%s' to '%s'\n", dev->bus_id,
1264 new_parent ? new_parent->bus_id : "<NULL>");
1265 error = kobject_move(&dev->kobj, new_parent_kobj);
1267 put_device(new_parent);
1270 old_parent = dev->parent;
1271 dev->parent = new_parent;
1273 klist_remove(&dev->knode_parent);
1275 klist_add_tail(&dev->knode_parent, &new_parent->klist_children);
1278 error = device_move_class_links(dev, old_parent, new_parent);
1280 /* We ignore errors on cleanup since we're hosed anyway... */
1281 device_move_class_links(dev, new_parent, old_parent);
1282 if (!kobject_move(&dev->kobj, &old_parent->kobj)) {
1284 klist_remove(&dev->knode_parent);
1286 klist_add_tail(&dev->knode_parent,
1287 &old_parent->klist_children);
1289 put_device(new_parent);
1293 put_device(old_parent);
1299 EXPORT_SYMBOL_GPL(device_move);