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 <linux/of_device.h>
23 #include <linux/genhd.h>
24 #include <linux/kallsyms.h>
25 #include <linux/mutex.h>
26 #include <linux/async.h>
27 #include <linux/pm_runtime.h>
28 #include <linux/netdevice.h>
31 #include "power/power.h"
33 #ifdef CONFIG_SYSFS_DEPRECATED
34 #ifdef CONFIG_SYSFS_DEPRECATED_V2
35 long sysfs_deprecated = 1;
37 long sysfs_deprecated = 0;
39 static __init int sysfs_deprecated_setup(char *arg)
41 return kstrtol(arg, 10, &sysfs_deprecated);
43 early_param("sysfs.deprecated", sysfs_deprecated_setup);
46 int (*platform_notify)(struct device *dev) = NULL;
47 int (*platform_notify_remove)(struct device *dev) = NULL;
48 static struct kobject *dev_kobj;
49 struct kobject *sysfs_dev_char_kobj;
50 struct kobject *sysfs_dev_block_kobj;
53 static inline int device_is_not_partition(struct device *dev)
55 return !(dev->type == &part_type);
58 static inline int device_is_not_partition(struct device *dev)
65 * dev_driver_string - Return a device's driver name, if at all possible
66 * @dev: struct device to get the name of
68 * Will return the device's driver's name if it is bound to a device. If
69 * the device is not bound to a driver, it will return the name of the bus
70 * it is attached to. If it is not attached to a bus either, an empty
71 * string will be returned.
73 const char *dev_driver_string(const struct device *dev)
75 struct device_driver *drv;
77 /* dev->driver can change to NULL underneath us because of unbinding,
78 * so be careful about accessing it. dev->bus and dev->class should
79 * never change once they are set, so they don't need special care.
81 drv = ACCESS_ONCE(dev->driver);
82 return drv ? drv->name :
83 (dev->bus ? dev->bus->name :
84 (dev->class ? dev->class->name : ""));
86 EXPORT_SYMBOL(dev_driver_string);
88 #define to_dev_attr(_attr) container_of(_attr, struct device_attribute, attr)
90 static ssize_t dev_attr_show(struct kobject *kobj, struct attribute *attr,
93 struct device_attribute *dev_attr = to_dev_attr(attr);
94 struct device *dev = kobj_to_dev(kobj);
98 ret = dev_attr->show(dev, dev_attr, buf);
99 if (ret >= (ssize_t)PAGE_SIZE) {
100 print_symbol("dev_attr_show: %s returned bad count\n",
101 (unsigned long)dev_attr->show);
106 static ssize_t dev_attr_store(struct kobject *kobj, struct attribute *attr,
107 const char *buf, size_t count)
109 struct device_attribute *dev_attr = to_dev_attr(attr);
110 struct device *dev = kobj_to_dev(kobj);
114 ret = dev_attr->store(dev, dev_attr, buf, count);
118 static const struct sysfs_ops dev_sysfs_ops = {
119 .show = dev_attr_show,
120 .store = dev_attr_store,
123 #define to_ext_attr(x) container_of(x, struct dev_ext_attribute, attr)
125 ssize_t device_store_ulong(struct device *dev,
126 struct device_attribute *attr,
127 const char *buf, size_t size)
129 struct dev_ext_attribute *ea = to_ext_attr(attr);
131 unsigned long new = simple_strtoul(buf, &end, 0);
134 *(unsigned long *)(ea->var) = new;
135 /* Always return full write size even if we didn't consume all */
138 EXPORT_SYMBOL_GPL(device_store_ulong);
140 ssize_t device_show_ulong(struct device *dev,
141 struct device_attribute *attr,
144 struct dev_ext_attribute *ea = to_ext_attr(attr);
145 return snprintf(buf, PAGE_SIZE, "%lx\n", *(unsigned long *)(ea->var));
147 EXPORT_SYMBOL_GPL(device_show_ulong);
149 ssize_t device_store_int(struct device *dev,
150 struct device_attribute *attr,
151 const char *buf, size_t size)
153 struct dev_ext_attribute *ea = to_ext_attr(attr);
155 long new = simple_strtol(buf, &end, 0);
156 if (end == buf || new > INT_MAX || new < INT_MIN)
158 *(int *)(ea->var) = new;
159 /* Always return full write size even if we didn't consume all */
162 EXPORT_SYMBOL_GPL(device_store_int);
164 ssize_t device_show_int(struct device *dev,
165 struct device_attribute *attr,
168 struct dev_ext_attribute *ea = to_ext_attr(attr);
170 return snprintf(buf, PAGE_SIZE, "%d\n", *(int *)(ea->var));
172 EXPORT_SYMBOL_GPL(device_show_int);
174 ssize_t device_store_bool(struct device *dev, struct device_attribute *attr,
175 const char *buf, size_t size)
177 struct dev_ext_attribute *ea = to_ext_attr(attr);
179 if (strtobool(buf, ea->var) < 0)
184 EXPORT_SYMBOL_GPL(device_store_bool);
186 ssize_t device_show_bool(struct device *dev, struct device_attribute *attr,
189 struct dev_ext_attribute *ea = to_ext_attr(attr);
191 return snprintf(buf, PAGE_SIZE, "%d\n", *(bool *)(ea->var));
193 EXPORT_SYMBOL_GPL(device_show_bool);
196 * device_release - free device structure.
197 * @kobj: device's kobject.
199 * This is called once the reference count for the object
200 * reaches 0. We forward the call to the device's release
201 * method, which should handle actually freeing the structure.
203 static void device_release(struct kobject *kobj)
205 struct device *dev = kobj_to_dev(kobj);
206 struct device_private *p = dev->p;
209 * Some platform devices are driven without driver attached
210 * and managed resources may have been acquired. Make sure
211 * all resources are released.
213 * Drivers still can add resources into device after device
214 * is deleted but alive, so release devres here to avoid
215 * possible memory leak.
217 devres_release_all(dev);
221 else if (dev->type && dev->type->release)
222 dev->type->release(dev);
223 else if (dev->class && dev->class->dev_release)
224 dev->class->dev_release(dev);
226 WARN(1, KERN_ERR "Device '%s' does not have a release() "
227 "function, it is broken and must be fixed.\n",
232 static const void *device_namespace(struct kobject *kobj)
234 struct device *dev = kobj_to_dev(kobj);
235 const void *ns = NULL;
237 if (dev->class && dev->class->ns_type)
238 ns = dev->class->namespace(dev);
243 static struct kobj_type device_ktype = {
244 .release = device_release,
245 .sysfs_ops = &dev_sysfs_ops,
246 .namespace = device_namespace,
250 static int dev_uevent_filter(struct kset *kset, struct kobject *kobj)
252 struct kobj_type *ktype = get_ktype(kobj);
254 if (ktype == &device_ktype) {
255 struct device *dev = kobj_to_dev(kobj);
264 static const char *dev_uevent_name(struct kset *kset, struct kobject *kobj)
266 struct device *dev = kobj_to_dev(kobj);
269 return dev->bus->name;
271 return dev->class->name;
275 static int dev_uevent(struct kset *kset, struct kobject *kobj,
276 struct kobj_uevent_env *env)
278 struct device *dev = kobj_to_dev(kobj);
281 /* add device node properties if present */
282 if (MAJOR(dev->devt)) {
286 kuid_t uid = GLOBAL_ROOT_UID;
287 kgid_t gid = GLOBAL_ROOT_GID;
289 add_uevent_var(env, "MAJOR=%u", MAJOR(dev->devt));
290 add_uevent_var(env, "MINOR=%u", MINOR(dev->devt));
291 name = device_get_devnode(dev, &mode, &uid, &gid, &tmp);
293 add_uevent_var(env, "DEVNAME=%s", name);
295 add_uevent_var(env, "DEVMODE=%#o", mode & 0777);
296 if (!uid_eq(uid, GLOBAL_ROOT_UID))
297 add_uevent_var(env, "DEVUID=%u", from_kuid(&init_user_ns, uid));
298 if (!gid_eq(gid, GLOBAL_ROOT_GID))
299 add_uevent_var(env, "DEVGID=%u", from_kgid(&init_user_ns, gid));
304 if (dev->type && dev->type->name)
305 add_uevent_var(env, "DEVTYPE=%s", dev->type->name);
308 add_uevent_var(env, "DRIVER=%s", dev->driver->name);
310 /* Add common DT information about the device */
311 of_device_uevent(dev, env);
313 /* have the bus specific function add its stuff */
314 if (dev->bus && dev->bus->uevent) {
315 retval = dev->bus->uevent(dev, env);
317 pr_debug("device: '%s': %s: bus uevent() returned %d\n",
318 dev_name(dev), __func__, retval);
321 /* have the class specific function add its stuff */
322 if (dev->class && dev->class->dev_uevent) {
323 retval = dev->class->dev_uevent(dev, env);
325 pr_debug("device: '%s': %s: class uevent() "
326 "returned %d\n", dev_name(dev),
330 /* have the device type specific function add its stuff */
331 if (dev->type && dev->type->uevent) {
332 retval = dev->type->uevent(dev, env);
334 pr_debug("device: '%s': %s: dev_type uevent() "
335 "returned %d\n", dev_name(dev),
342 static const struct kset_uevent_ops device_uevent_ops = {
343 .filter = dev_uevent_filter,
344 .name = dev_uevent_name,
345 .uevent = dev_uevent,
348 static ssize_t show_uevent(struct device *dev, struct device_attribute *attr,
351 struct kobject *top_kobj;
353 struct kobj_uevent_env *env = NULL;
358 /* search the kset, the device belongs to */
359 top_kobj = &dev->kobj;
360 while (!top_kobj->kset && top_kobj->parent)
361 top_kobj = top_kobj->parent;
365 kset = top_kobj->kset;
366 if (!kset->uevent_ops || !kset->uevent_ops->uevent)
370 if (kset->uevent_ops && kset->uevent_ops->filter)
371 if (!kset->uevent_ops->filter(kset, &dev->kobj))
374 env = kzalloc(sizeof(struct kobj_uevent_env), GFP_KERNEL);
378 /* let the kset specific function add its keys */
379 retval = kset->uevent_ops->uevent(kset, &dev->kobj, env);
383 /* copy keys to file */
384 for (i = 0; i < env->envp_idx; i++)
385 count += sprintf(&buf[count], "%s\n", env->envp[i]);
391 static ssize_t store_uevent(struct device *dev, struct device_attribute *attr,
392 const char *buf, size_t count)
394 enum kobject_action action;
396 if (kobject_action_type(buf, count, &action) == 0)
397 kobject_uevent(&dev->kobj, action);
399 dev_err(dev, "uevent: unknown action-string\n");
403 static struct device_attribute uevent_attr =
404 __ATTR(uevent, S_IRUGO | S_IWUSR, show_uevent, store_uevent);
406 static ssize_t show_online(struct device *dev, struct device_attribute *attr,
411 lock_device_hotplug();
413 unlock_device_hotplug();
414 return sprintf(buf, "%u\n", val);
417 static ssize_t store_online(struct device *dev, struct device_attribute *attr,
418 const char *buf, size_t count)
423 ret = strtobool(buf, &val);
427 lock_device_hotplug();
428 ret = val ? device_online(dev) : device_offline(dev);
429 unlock_device_hotplug();
430 return ret < 0 ? ret : count;
433 static struct device_attribute online_attr =
434 __ATTR(online, S_IRUGO | S_IWUSR, show_online, store_online);
436 static int device_add_attributes(struct device *dev,
437 struct device_attribute *attrs)
443 for (i = 0; attr_name(attrs[i]); i++) {
444 error = device_create_file(dev, &attrs[i]);
450 device_remove_file(dev, &attrs[i]);
455 static void device_remove_attributes(struct device *dev,
456 struct device_attribute *attrs)
461 for (i = 0; attr_name(attrs[i]); i++)
462 device_remove_file(dev, &attrs[i]);
465 static int device_add_bin_attributes(struct device *dev,
466 struct bin_attribute *attrs)
472 for (i = 0; attr_name(attrs[i]); i++) {
473 error = device_create_bin_file(dev, &attrs[i]);
479 device_remove_bin_file(dev, &attrs[i]);
484 static void device_remove_bin_attributes(struct device *dev,
485 struct bin_attribute *attrs)
490 for (i = 0; attr_name(attrs[i]); i++)
491 device_remove_bin_file(dev, &attrs[i]);
494 int device_add_groups(struct device *dev, const struct attribute_group **groups)
500 for (i = 0; groups[i]; i++) {
501 error = sysfs_create_group(&dev->kobj, groups[i]);
504 sysfs_remove_group(&dev->kobj,
513 void device_remove_groups(struct device *dev,
514 const struct attribute_group **groups)
519 for (i = 0; groups[i]; i++)
520 sysfs_remove_group(&dev->kobj, groups[i]);
523 static int device_add_attrs(struct device *dev)
525 struct class *class = dev->class;
526 const struct device_type *type = dev->type;
530 error = device_add_groups(dev, class->dev_groups);
533 error = device_add_attributes(dev, class->dev_attrs);
535 goto err_remove_class_groups;
536 error = device_add_bin_attributes(dev, class->dev_bin_attrs);
538 goto err_remove_class_attrs;
542 error = device_add_groups(dev, type->groups);
544 goto err_remove_class_bin_attrs;
547 error = device_add_groups(dev, dev->groups);
549 goto err_remove_type_groups;
551 if (device_supports_offline(dev) && !dev->offline_disabled) {
552 error = device_create_file(dev, &online_attr);
554 goto err_remove_type_groups;
559 err_remove_type_groups:
561 device_remove_groups(dev, type->groups);
562 err_remove_class_bin_attrs:
564 device_remove_bin_attributes(dev, class->dev_bin_attrs);
565 err_remove_class_attrs:
567 device_remove_attributes(dev, class->dev_attrs);
568 err_remove_class_groups:
570 device_remove_groups(dev, class->dev_groups);
575 static void device_remove_attrs(struct device *dev)
577 struct class *class = dev->class;
578 const struct device_type *type = dev->type;
580 device_remove_file(dev, &online_attr);
581 device_remove_groups(dev, dev->groups);
584 device_remove_groups(dev, type->groups);
587 device_remove_attributes(dev, class->dev_attrs);
588 device_remove_bin_attributes(dev, class->dev_bin_attrs);
589 device_remove_groups(dev, class->dev_groups);
594 static ssize_t show_dev(struct device *dev, struct device_attribute *attr,
597 return print_dev_t(buf, dev->devt);
600 static struct device_attribute devt_attr =
601 __ATTR(dev, S_IRUGO, show_dev, NULL);
604 struct kset *devices_kset;
607 * device_create_file - create sysfs attribute file for device.
609 * @attr: device attribute descriptor.
611 int device_create_file(struct device *dev,
612 const struct device_attribute *attr)
617 WARN(((attr->attr.mode & S_IWUGO) && !attr->store),
618 "Attribute %s: write permission without 'store'\n",
620 WARN(((attr->attr.mode & S_IRUGO) && !attr->show),
621 "Attribute %s: read permission without 'show'\n",
623 error = sysfs_create_file(&dev->kobj, &attr->attr);
628 EXPORT_SYMBOL_GPL(device_create_file);
631 * device_remove_file - remove sysfs attribute file.
633 * @attr: device attribute descriptor.
635 void device_remove_file(struct device *dev,
636 const struct device_attribute *attr)
639 sysfs_remove_file(&dev->kobj, &attr->attr);
641 EXPORT_SYMBOL_GPL(device_remove_file);
644 * device_create_bin_file - create sysfs binary attribute file for device.
646 * @attr: device binary attribute descriptor.
648 int device_create_bin_file(struct device *dev,
649 const struct bin_attribute *attr)
653 error = sysfs_create_bin_file(&dev->kobj, attr);
656 EXPORT_SYMBOL_GPL(device_create_bin_file);
659 * device_remove_bin_file - remove sysfs binary attribute file
661 * @attr: device binary attribute descriptor.
663 void device_remove_bin_file(struct device *dev,
664 const struct bin_attribute *attr)
667 sysfs_remove_bin_file(&dev->kobj, attr);
669 EXPORT_SYMBOL_GPL(device_remove_bin_file);
672 * device_schedule_callback_owner - helper to schedule a callback for a device
674 * @func: callback function to invoke later.
675 * @owner: module owning the callback routine
677 * Attribute methods must not unregister themselves or their parent device
678 * (which would amount to the same thing). Attempts to do so will deadlock,
679 * since unregistration is mutually exclusive with driver callbacks.
681 * Instead methods can call this routine, which will attempt to allocate
682 * and schedule a workqueue request to call back @func with @dev as its
683 * argument in the workqueue's process context. @dev will be pinned until
686 * This routine is usually called via the inline device_schedule_callback(),
687 * which automatically sets @owner to THIS_MODULE.
689 * Returns 0 if the request was submitted, -ENOMEM if storage could not
690 * be allocated, -ENODEV if a reference to @owner isn't available.
692 * NOTE: This routine won't work if CONFIG_SYSFS isn't set! It uses an
693 * underlying sysfs routine (since it is intended for use by attribute
694 * methods), and if sysfs isn't available you'll get nothing but -ENOSYS.
696 int device_schedule_callback_owner(struct device *dev,
697 void (*func)(struct device *), struct module *owner)
699 return sysfs_schedule_callback(&dev->kobj,
700 (void (*)(void *)) func, dev, owner);
702 EXPORT_SYMBOL_GPL(device_schedule_callback_owner);
704 static void klist_children_get(struct klist_node *n)
706 struct device_private *p = to_device_private_parent(n);
707 struct device *dev = p->device;
712 static void klist_children_put(struct klist_node *n)
714 struct device_private *p = to_device_private_parent(n);
715 struct device *dev = p->device;
721 * device_initialize - init device structure.
724 * This prepares the device for use by other layers by initializing
726 * It is the first half of device_register(), if called by
727 * that function, though it can also be called separately, so one
728 * may use @dev's fields. In particular, get_device()/put_device()
729 * may be used for reference counting of @dev after calling this
732 * All fields in @dev must be initialized by the caller to 0, except
733 * for those explicitly set to some other value. The simplest
734 * approach is to use kzalloc() to allocate the structure containing
737 * NOTE: Use put_device() to give up your reference instead of freeing
738 * @dev directly once you have called this function.
740 void device_initialize(struct device *dev)
742 dev->kobj.kset = devices_kset;
743 kobject_init(&dev->kobj, &device_ktype);
744 INIT_LIST_HEAD(&dev->dma_pools);
745 mutex_init(&dev->mutex);
746 lockdep_set_novalidate_class(&dev->mutex);
747 spin_lock_init(&dev->devres_lock);
748 INIT_LIST_HEAD(&dev->devres_head);
750 set_dev_node(dev, -1);
752 EXPORT_SYMBOL_GPL(device_initialize);
754 struct kobject *virtual_device_parent(struct device *dev)
756 static struct kobject *virtual_dir = NULL;
759 virtual_dir = kobject_create_and_add("virtual",
760 &devices_kset->kobj);
770 #define to_class_dir(obj) container_of(obj, struct class_dir, kobj)
772 static void class_dir_release(struct kobject *kobj)
774 struct class_dir *dir = to_class_dir(kobj);
779 struct kobj_ns_type_operations *class_dir_child_ns_type(struct kobject *kobj)
781 struct class_dir *dir = to_class_dir(kobj);
782 return dir->class->ns_type;
785 static struct kobj_type class_dir_ktype = {
786 .release = class_dir_release,
787 .sysfs_ops = &kobj_sysfs_ops,
788 .child_ns_type = class_dir_child_ns_type
791 static struct kobject *
792 class_dir_create_and_add(struct class *class, struct kobject *parent_kobj)
794 struct class_dir *dir;
797 dir = kzalloc(sizeof(*dir), GFP_KERNEL);
802 kobject_init(&dir->kobj, &class_dir_ktype);
804 dir->kobj.kset = &class->p->glue_dirs;
806 retval = kobject_add(&dir->kobj, parent_kobj, "%s", class->name);
808 kobject_put(&dir->kobj);
815 static struct kobject *get_device_parent(struct device *dev,
816 struct device *parent)
819 static DEFINE_MUTEX(gdp_mutex);
820 struct kobject *kobj = NULL;
821 struct kobject *parent_kobj;
825 /* block disks show up in /sys/block */
826 if (sysfs_deprecated && dev->class == &block_class) {
827 if (parent && parent->class == &block_class)
828 return &parent->kobj;
829 return &block_class.p->subsys.kobj;
834 * If we have no parent, we live in "virtual".
835 * Class-devices with a non class-device as parent, live
836 * in a "glue" directory to prevent namespace collisions.
839 parent_kobj = virtual_device_parent(dev);
840 else if (parent->class && !dev->class->ns_type)
841 return &parent->kobj;
843 parent_kobj = &parent->kobj;
845 mutex_lock(&gdp_mutex);
847 /* find our class-directory at the parent and reference it */
848 spin_lock(&dev->class->p->glue_dirs.list_lock);
849 list_for_each_entry(k, &dev->class->p->glue_dirs.list, entry)
850 if (k->parent == parent_kobj) {
851 kobj = kobject_get(k);
854 spin_unlock(&dev->class->p->glue_dirs.list_lock);
856 mutex_unlock(&gdp_mutex);
860 /* or create a new class-directory at the parent device */
861 k = class_dir_create_and_add(dev->class, parent_kobj);
862 /* do not emit an uevent for this simple "glue" directory */
863 mutex_unlock(&gdp_mutex);
867 /* subsystems can specify a default root directory for their devices */
868 if (!parent && dev->bus && dev->bus->dev_root)
869 return &dev->bus->dev_root->kobj;
872 return &parent->kobj;
876 static void cleanup_glue_dir(struct device *dev, struct kobject *glue_dir)
878 /* see if we live in a "glue" directory */
879 if (!glue_dir || !dev->class ||
880 glue_dir->kset != &dev->class->p->glue_dirs)
883 kobject_put(glue_dir);
886 static void cleanup_device_parent(struct device *dev)
888 cleanup_glue_dir(dev, dev->kobj.parent);
891 static int device_add_class_symlinks(struct device *dev)
898 error = sysfs_create_link(&dev->kobj,
899 &dev->class->p->subsys.kobj,
904 if (dev->parent && device_is_not_partition(dev)) {
905 error = sysfs_create_link(&dev->kobj, &dev->parent->kobj,
912 /* /sys/block has directories and does not need symlinks */
913 if (sysfs_deprecated && dev->class == &block_class)
917 /* link in the class directory pointing to the device */
918 error = sysfs_create_link(&dev->class->p->subsys.kobj,
919 &dev->kobj, dev_name(dev));
926 sysfs_remove_link(&dev->kobj, "device");
929 sysfs_remove_link(&dev->kobj, "subsystem");
934 static void device_remove_class_symlinks(struct device *dev)
939 if (dev->parent && device_is_not_partition(dev))
940 sysfs_remove_link(&dev->kobj, "device");
941 sysfs_remove_link(&dev->kobj, "subsystem");
943 if (sysfs_deprecated && dev->class == &block_class)
946 sysfs_delete_link(&dev->class->p->subsys.kobj, &dev->kobj, dev_name(dev));
950 * dev_set_name - set a device name
952 * @fmt: format string for the device's name
954 int dev_set_name(struct device *dev, const char *fmt, ...)
959 va_start(vargs, fmt);
960 err = kobject_set_name_vargs(&dev->kobj, fmt, vargs);
964 EXPORT_SYMBOL_GPL(dev_set_name);
967 * device_to_dev_kobj - select a /sys/dev/ directory for the device
970 * By default we select char/ for new entries. Setting class->dev_obj
971 * to NULL prevents an entry from being created. class->dev_kobj must
972 * be set (or cleared) before any devices are registered to the class
973 * otherwise device_create_sys_dev_entry() and
974 * device_remove_sys_dev_entry() will disagree about the presence of
977 static struct kobject *device_to_dev_kobj(struct device *dev)
979 struct kobject *kobj;
982 kobj = dev->class->dev_kobj;
984 kobj = sysfs_dev_char_kobj;
989 static int device_create_sys_dev_entry(struct device *dev)
991 struct kobject *kobj = device_to_dev_kobj(dev);
996 format_dev_t(devt_str, dev->devt);
997 error = sysfs_create_link(kobj, &dev->kobj, devt_str);
1003 static void device_remove_sys_dev_entry(struct device *dev)
1005 struct kobject *kobj = device_to_dev_kobj(dev);
1009 format_dev_t(devt_str, dev->devt);
1010 sysfs_remove_link(kobj, devt_str);
1014 int device_private_init(struct device *dev)
1016 dev->p = kzalloc(sizeof(*dev->p), GFP_KERNEL);
1019 dev->p->device = dev;
1020 klist_init(&dev->p->klist_children, klist_children_get,
1021 klist_children_put);
1022 INIT_LIST_HEAD(&dev->p->deferred_probe);
1027 * device_add - add device to device hierarchy.
1030 * This is part 2 of device_register(), though may be called
1031 * separately _iff_ device_initialize() has been called separately.
1033 * This adds @dev to the kobject hierarchy via kobject_add(), adds it
1034 * to the global and sibling lists for the device, then
1035 * adds it to the other relevant subsystems of the driver model.
1037 * Do not call this routine or device_register() more than once for
1038 * any device structure. The driver model core is not designed to work
1039 * with devices that get unregistered and then spring back to life.
1040 * (Among other things, it's very hard to guarantee that all references
1041 * to the previous incarnation of @dev have been dropped.) Allocate
1042 * and register a fresh new struct device instead.
1044 * NOTE: _Never_ directly free @dev after calling this function, even
1045 * if it returned an error! Always use put_device() to give up your
1046 * reference instead.
1048 int device_add(struct device *dev)
1050 struct device *parent = NULL;
1051 struct kobject *kobj;
1052 struct class_interface *class_intf;
1053 int error = -EINVAL;
1055 dev = get_device(dev);
1060 error = device_private_init(dev);
1066 * for statically allocated devices, which should all be converted
1067 * some day, we need to initialize the name. We prevent reading back
1068 * the name, and force the use of dev_name()
1070 if (dev->init_name) {
1071 dev_set_name(dev, "%s", dev->init_name);
1072 dev->init_name = NULL;
1075 /* subsystems can specify simple device enumeration */
1076 if (!dev_name(dev) && dev->bus && dev->bus->dev_name)
1077 dev_set_name(dev, "%s%u", dev->bus->dev_name, dev->id);
1079 if (!dev_name(dev)) {
1084 pr_debug("device: '%s': %s\n", dev_name(dev), __func__);
1086 parent = get_device(dev->parent);
1087 kobj = get_device_parent(dev, parent);
1089 dev->kobj.parent = kobj;
1091 /* use parent numa_node */
1093 set_dev_node(dev, dev_to_node(parent));
1095 /* first, register with generic layer. */
1096 /* we require the name to be set before, and pass NULL */
1097 error = kobject_add(&dev->kobj, dev->kobj.parent, NULL);
1101 /* notify platform of device entry */
1102 if (platform_notify)
1103 platform_notify(dev);
1105 error = device_create_file(dev, &uevent_attr);
1109 if (MAJOR(dev->devt)) {
1110 error = device_create_file(dev, &devt_attr);
1112 goto ueventattrError;
1114 error = device_create_sys_dev_entry(dev);
1118 devtmpfs_create_node(dev);
1121 error = device_add_class_symlinks(dev);
1124 error = device_add_attrs(dev);
1127 error = bus_add_device(dev);
1130 error = dpm_sysfs_add(dev);
1135 /* Notify clients of device addition. This call must come
1136 * after dpm_sysfs_add() and before kobject_uevent().
1139 blocking_notifier_call_chain(&dev->bus->p->bus_notifier,
1140 BUS_NOTIFY_ADD_DEVICE, dev);
1142 kobject_uevent(&dev->kobj, KOBJ_ADD);
1143 bus_probe_device(dev);
1145 klist_add_tail(&dev->p->knode_parent,
1146 &parent->p->klist_children);
1149 mutex_lock(&dev->class->p->mutex);
1150 /* tie the class to the device */
1151 klist_add_tail(&dev->knode_class,
1152 &dev->class->p->klist_devices);
1154 /* notify any interfaces that the device is here */
1155 list_for_each_entry(class_intf,
1156 &dev->class->p->interfaces, node)
1157 if (class_intf->add_dev)
1158 class_intf->add_dev(dev, class_intf);
1159 mutex_unlock(&dev->class->p->mutex);
1165 bus_remove_device(dev);
1167 device_remove_attrs(dev);
1169 device_remove_class_symlinks(dev);
1171 if (MAJOR(dev->devt))
1172 devtmpfs_delete_node(dev);
1173 if (MAJOR(dev->devt))
1174 device_remove_sys_dev_entry(dev);
1176 if (MAJOR(dev->devt))
1177 device_remove_file(dev, &devt_attr);
1179 device_remove_file(dev, &uevent_attr);
1181 kobject_uevent(&dev->kobj, KOBJ_REMOVE);
1182 kobject_del(&dev->kobj);
1184 cleanup_device_parent(dev);
1192 EXPORT_SYMBOL_GPL(device_add);
1195 * device_register - register a device with the system.
1196 * @dev: pointer to the device structure
1198 * This happens in two clean steps - initialize the device
1199 * and add it to the system. The two steps can be called
1200 * separately, but this is the easiest and most common.
1201 * I.e. you should only call the two helpers separately if
1202 * have a clearly defined need to use and refcount the device
1203 * before it is added to the hierarchy.
1205 * For more information, see the kerneldoc for device_initialize()
1208 * NOTE: _Never_ directly free @dev after calling this function, even
1209 * if it returned an error! Always use put_device() to give up the
1210 * reference initialized in this function instead.
1212 int device_register(struct device *dev)
1214 device_initialize(dev);
1215 return device_add(dev);
1217 EXPORT_SYMBOL_GPL(device_register);
1220 * get_device - increment reference count for device.
1223 * This simply forwards the call to kobject_get(), though
1224 * we do take care to provide for the case that we get a NULL
1225 * pointer passed in.
1227 struct device *get_device(struct device *dev)
1229 return dev ? kobj_to_dev(kobject_get(&dev->kobj)) : NULL;
1231 EXPORT_SYMBOL_GPL(get_device);
1234 * put_device - decrement reference count.
1235 * @dev: device in question.
1237 void put_device(struct device *dev)
1239 /* might_sleep(); */
1241 kobject_put(&dev->kobj);
1243 EXPORT_SYMBOL_GPL(put_device);
1246 * device_del - delete device from system.
1249 * This is the first part of the device unregistration
1250 * sequence. This removes the device from the lists we control
1251 * from here, has it removed from the other driver model
1252 * subsystems it was added to in device_add(), and removes it
1253 * from the kobject hierarchy.
1255 * NOTE: this should be called manually _iff_ device_add() was
1256 * also called manually.
1258 void device_del(struct device *dev)
1260 struct device *parent = dev->parent;
1261 struct class_interface *class_intf;
1263 /* Notify clients of device removal. This call must come
1264 * before dpm_sysfs_remove().
1267 blocking_notifier_call_chain(&dev->bus->p->bus_notifier,
1268 BUS_NOTIFY_DEL_DEVICE, dev);
1269 dpm_sysfs_remove(dev);
1271 klist_del(&dev->p->knode_parent);
1272 if (MAJOR(dev->devt)) {
1273 devtmpfs_delete_node(dev);
1274 device_remove_sys_dev_entry(dev);
1275 device_remove_file(dev, &devt_attr);
1278 device_remove_class_symlinks(dev);
1280 mutex_lock(&dev->class->p->mutex);
1281 /* notify any interfaces that the device is now gone */
1282 list_for_each_entry(class_intf,
1283 &dev->class->p->interfaces, node)
1284 if (class_intf->remove_dev)
1285 class_intf->remove_dev(dev, class_intf);
1286 /* remove the device from the class list */
1287 klist_del(&dev->knode_class);
1288 mutex_unlock(&dev->class->p->mutex);
1290 device_remove_file(dev, &uevent_attr);
1291 device_remove_attrs(dev);
1292 bus_remove_device(dev);
1293 device_pm_remove(dev);
1294 driver_deferred_probe_del(dev);
1296 /* Notify the platform of the removal, in case they
1297 * need to do anything...
1299 if (platform_notify_remove)
1300 platform_notify_remove(dev);
1301 kobject_uevent(&dev->kobj, KOBJ_REMOVE);
1302 cleanup_device_parent(dev);
1303 kobject_del(&dev->kobj);
1306 EXPORT_SYMBOL_GPL(device_del);
1309 * device_unregister - unregister device from system.
1310 * @dev: device going away.
1312 * We do this in two parts, like we do device_register(). First,
1313 * we remove it from all the subsystems with device_del(), then
1314 * we decrement the reference count via put_device(). If that
1315 * is the final reference count, the device will be cleaned up
1316 * via device_release() above. Otherwise, the structure will
1317 * stick around until the final reference to the device is dropped.
1319 void device_unregister(struct device *dev)
1321 pr_debug("device: '%s': %s\n", dev_name(dev), __func__);
1325 EXPORT_SYMBOL_GPL(device_unregister);
1327 static struct device *next_device(struct klist_iter *i)
1329 struct klist_node *n = klist_next(i);
1330 struct device *dev = NULL;
1331 struct device_private *p;
1334 p = to_device_private_parent(n);
1341 * device_get_devnode - path of device node file
1343 * @mode: returned file access mode
1344 * @uid: returned file owner
1345 * @gid: returned file group
1346 * @tmp: possibly allocated string
1348 * Return the relative path of a possible device node.
1349 * Non-default names may need to allocate a memory to compose
1350 * a name. This memory is returned in tmp and needs to be
1351 * freed by the caller.
1353 const char *device_get_devnode(struct device *dev,
1354 umode_t *mode, kuid_t *uid, kgid_t *gid,
1361 /* the device type may provide a specific name */
1362 if (dev->type && dev->type->devnode)
1363 *tmp = dev->type->devnode(dev, mode, uid, gid);
1367 /* the class may provide a specific name */
1368 if (dev->class && dev->class->devnode)
1369 *tmp = dev->class->devnode(dev, mode);
1373 /* return name without allocation, tmp == NULL */
1374 if (strchr(dev_name(dev), '!') == NULL)
1375 return dev_name(dev);
1377 /* replace '!' in the name with '/' */
1378 *tmp = kstrdup(dev_name(dev), GFP_KERNEL);
1381 while ((s = strchr(*tmp, '!')))
1387 * device_for_each_child - device child iterator.
1388 * @parent: parent struct device.
1389 * @fn: function to be called for each device.
1390 * @data: data for the callback.
1392 * Iterate over @parent's child devices, and call @fn for each,
1395 * We check the return of @fn each time. If it returns anything
1396 * other than 0, we break out and return that value.
1398 int device_for_each_child(struct device *parent, void *data,
1399 int (*fn)(struct device *dev, void *data))
1401 struct klist_iter i;
1402 struct device *child;
1408 klist_iter_init(&parent->p->klist_children, &i);
1409 while ((child = next_device(&i)) && !error)
1410 error = fn(child, data);
1411 klist_iter_exit(&i);
1414 EXPORT_SYMBOL_GPL(device_for_each_child);
1417 * device_find_child - device iterator for locating a particular device.
1418 * @parent: parent struct device
1419 * @match: Callback function to check device
1420 * @data: Data to pass to match function
1422 * This is similar to the device_for_each_child() function above, but it
1423 * returns a reference to a device that is 'found' for later use, as
1424 * determined by the @match callback.
1426 * The callback should return 0 if the device doesn't match and non-zero
1427 * if it does. If the callback returns non-zero and a reference to the
1428 * current device can be obtained, this function will return to the caller
1429 * and not iterate over any more devices.
1431 * NOTE: you will need to drop the reference with put_device() after use.
1433 struct device *device_find_child(struct device *parent, void *data,
1434 int (*match)(struct device *dev, void *data))
1436 struct klist_iter i;
1437 struct device *child;
1442 klist_iter_init(&parent->p->klist_children, &i);
1443 while ((child = next_device(&i)))
1444 if (match(child, data) && get_device(child))
1446 klist_iter_exit(&i);
1449 EXPORT_SYMBOL_GPL(device_find_child);
1451 int __init devices_init(void)
1453 devices_kset = kset_create_and_add("devices", &device_uevent_ops, NULL);
1456 dev_kobj = kobject_create_and_add("dev", NULL);
1459 sysfs_dev_block_kobj = kobject_create_and_add("block", dev_kobj);
1460 if (!sysfs_dev_block_kobj)
1461 goto block_kobj_err;
1462 sysfs_dev_char_kobj = kobject_create_and_add("char", dev_kobj);
1463 if (!sysfs_dev_char_kobj)
1469 kobject_put(sysfs_dev_block_kobj);
1471 kobject_put(dev_kobj);
1473 kset_unregister(devices_kset);
1477 static DEFINE_MUTEX(device_hotplug_lock);
1479 void lock_device_hotplug(void)
1481 mutex_lock(&device_hotplug_lock);
1484 void unlock_device_hotplug(void)
1486 mutex_unlock(&device_hotplug_lock);
1489 static int device_check_offline(struct device *dev, void *not_used)
1493 ret = device_for_each_child(dev, NULL, device_check_offline);
1497 return device_supports_offline(dev) && !dev->offline ? -EBUSY : 0;
1501 * device_offline - Prepare the device for hot-removal.
1502 * @dev: Device to be put offline.
1504 * Execute the device bus type's .offline() callback, if present, to prepare
1505 * the device for a subsequent hot-removal. If that succeeds, the device must
1506 * not be used until either it is removed or its bus type's .online() callback
1509 * Call under device_hotplug_lock.
1511 int device_offline(struct device *dev)
1515 if (dev->offline_disabled)
1518 ret = device_for_each_child(dev, NULL, device_check_offline);
1523 if (device_supports_offline(dev)) {
1527 ret = dev->bus->offline(dev);
1529 kobject_uevent(&dev->kobj, KOBJ_OFFLINE);
1530 dev->offline = true;
1540 * device_online - Put the device back online after successful device_offline().
1541 * @dev: Device to be put back online.
1543 * If device_offline() has been successfully executed for @dev, but the device
1544 * has not been removed subsequently, execute its bus type's .online() callback
1545 * to indicate that the device can be used again.
1547 * Call under device_hotplug_lock.
1549 int device_online(struct device *dev)
1554 if (device_supports_offline(dev)) {
1556 ret = dev->bus->online(dev);
1558 kobject_uevent(&dev->kobj, KOBJ_ONLINE);
1559 dev->offline = false;
1570 struct root_device {
1572 struct module *owner;
1575 static inline struct root_device *to_root_device(struct device *d)
1577 return container_of(d, struct root_device, dev);
1580 static void root_device_release(struct device *dev)
1582 kfree(to_root_device(dev));
1586 * __root_device_register - allocate and register a root device
1587 * @name: root device name
1588 * @owner: owner module of the root device, usually THIS_MODULE
1590 * This function allocates a root device and registers it
1591 * using device_register(). In order to free the returned
1592 * device, use root_device_unregister().
1594 * Root devices are dummy devices which allow other devices
1595 * to be grouped under /sys/devices. Use this function to
1596 * allocate a root device and then use it as the parent of
1597 * any device which should appear under /sys/devices/{name}
1599 * The /sys/devices/{name} directory will also contain a
1600 * 'module' symlink which points to the @owner directory
1603 * Returns &struct device pointer on success, or ERR_PTR() on error.
1605 * Note: You probably want to use root_device_register().
1607 struct device *__root_device_register(const char *name, struct module *owner)
1609 struct root_device *root;
1612 root = kzalloc(sizeof(struct root_device), GFP_KERNEL);
1614 return ERR_PTR(err);
1616 err = dev_set_name(&root->dev, "%s", name);
1619 return ERR_PTR(err);
1622 root->dev.release = root_device_release;
1624 err = device_register(&root->dev);
1626 put_device(&root->dev);
1627 return ERR_PTR(err);
1630 #ifdef CONFIG_MODULES /* gotta find a "cleaner" way to do this */
1632 struct module_kobject *mk = &owner->mkobj;
1634 err = sysfs_create_link(&root->dev.kobj, &mk->kobj, "module");
1636 device_unregister(&root->dev);
1637 return ERR_PTR(err);
1639 root->owner = owner;
1645 EXPORT_SYMBOL_GPL(__root_device_register);
1648 * root_device_unregister - unregister and free a root device
1649 * @dev: device going away
1651 * This function unregisters and cleans up a device that was created by
1652 * root_device_register().
1654 void root_device_unregister(struct device *dev)
1656 struct root_device *root = to_root_device(dev);
1659 sysfs_remove_link(&root->dev.kobj, "module");
1661 device_unregister(dev);
1663 EXPORT_SYMBOL_GPL(root_device_unregister);
1666 static void device_create_release(struct device *dev)
1668 pr_debug("device: '%s': %s\n", dev_name(dev), __func__);
1672 static struct device *
1673 device_create_groups_vargs(struct class *class, struct device *parent,
1674 dev_t devt, void *drvdata,
1675 const struct attribute_group **groups,
1676 const char *fmt, va_list args)
1678 struct device *dev = NULL;
1679 int retval = -ENODEV;
1681 if (class == NULL || IS_ERR(class))
1684 dev = kzalloc(sizeof(*dev), GFP_KERNEL);
1692 dev->parent = parent;
1693 dev->groups = groups;
1694 dev->release = device_create_release;
1695 dev_set_drvdata(dev, drvdata);
1697 retval = kobject_set_name_vargs(&dev->kobj, fmt, args);
1701 retval = device_register(dev);
1709 return ERR_PTR(retval);
1713 * device_create_vargs - creates a device and registers it with sysfs
1714 * @class: pointer to the struct class that this device should be registered to
1715 * @parent: pointer to the parent struct device of this new device, if any
1716 * @devt: the dev_t for the char device to be added
1717 * @drvdata: the data to be added to the device for callbacks
1718 * @fmt: string for the device's name
1719 * @args: va_list for the device's name
1721 * This function can be used by char device classes. A struct device
1722 * will be created in sysfs, registered to the specified class.
1724 * A "dev" file will be created, showing the dev_t for the device, if
1725 * the dev_t is not 0,0.
1726 * If a pointer to a parent struct device is passed in, the newly created
1727 * struct device will be a child of that device in sysfs.
1728 * The pointer to the struct device will be returned from the call.
1729 * Any further sysfs files that might be required can be created using this
1732 * Returns &struct device pointer on success, or ERR_PTR() on error.
1734 * Note: the struct class passed to this function must have previously
1735 * been created with a call to class_create().
1737 struct device *device_create_vargs(struct class *class, struct device *parent,
1738 dev_t devt, void *drvdata, const char *fmt,
1741 return device_create_groups_vargs(class, parent, devt, drvdata, NULL,
1744 EXPORT_SYMBOL_GPL(device_create_vargs);
1747 * device_create - creates a device and registers it with sysfs
1748 * @class: pointer to the struct class that this device should be registered to
1749 * @parent: pointer to the parent struct device of this new device, if any
1750 * @devt: the dev_t for the char device to be added
1751 * @drvdata: the data to be added to the device for callbacks
1752 * @fmt: string for the device's name
1754 * This function can be used by char device classes. A struct device
1755 * will be created in sysfs, registered to the specified class.
1757 * A "dev" file will be created, showing the dev_t for the device, if
1758 * the dev_t is not 0,0.
1759 * If a pointer to a parent struct device is passed in, the newly created
1760 * struct device will be a child of that device in sysfs.
1761 * The pointer to the struct device will be returned from the call.
1762 * Any further sysfs files that might be required can be created using this
1765 * Returns &struct device pointer on success, or ERR_PTR() on error.
1767 * Note: the struct class passed to this function must have previously
1768 * been created with a call to class_create().
1770 struct device *device_create(struct class *class, struct device *parent,
1771 dev_t devt, void *drvdata, const char *fmt, ...)
1776 va_start(vargs, fmt);
1777 dev = device_create_vargs(class, parent, devt, drvdata, fmt, vargs);
1781 EXPORT_SYMBOL_GPL(device_create);
1784 * device_create_with_groups - creates a device and registers it with sysfs
1785 * @class: pointer to the struct class that this device should be registered to
1786 * @parent: pointer to the parent struct device of this new device, if any
1787 * @devt: the dev_t for the char device to be added
1788 * @drvdata: the data to be added to the device for callbacks
1789 * @groups: NULL-terminated list of attribute groups to be created
1790 * @fmt: string for the device's name
1792 * This function can be used by char device classes. A struct device
1793 * will be created in sysfs, registered to the specified class.
1794 * Additional attributes specified in the groups parameter will also
1795 * be created automatically.
1797 * A "dev" file will be created, showing the dev_t for the device, if
1798 * the dev_t is not 0,0.
1799 * If a pointer to a parent struct device is passed in, the newly created
1800 * struct device will be a child of that device in sysfs.
1801 * The pointer to the struct device will be returned from the call.
1802 * Any further sysfs files that might be required can be created using this
1805 * Returns &struct device pointer on success, or ERR_PTR() on error.
1807 * Note: the struct class passed to this function must have previously
1808 * been created with a call to class_create().
1810 struct device *device_create_with_groups(struct class *class,
1811 struct device *parent, dev_t devt,
1813 const struct attribute_group **groups,
1814 const char *fmt, ...)
1819 va_start(vargs, fmt);
1820 dev = device_create_groups_vargs(class, parent, devt, drvdata, groups,
1825 EXPORT_SYMBOL_GPL(device_create_with_groups);
1827 static int __match_devt(struct device *dev, const void *data)
1829 const dev_t *devt = data;
1831 return dev->devt == *devt;
1835 * device_destroy - removes a device that was created with device_create()
1836 * @class: pointer to the struct class that this device was registered with
1837 * @devt: the dev_t of the device that was previously registered
1839 * This call unregisters and cleans up a device that was created with a
1840 * call to device_create().
1842 void device_destroy(struct class *class, dev_t devt)
1846 dev = class_find_device(class, NULL, &devt, __match_devt);
1849 device_unregister(dev);
1852 EXPORT_SYMBOL_GPL(device_destroy);
1855 * device_rename - renames a device
1856 * @dev: the pointer to the struct device to be renamed
1857 * @new_name: the new name of the device
1859 * It is the responsibility of the caller to provide mutual
1860 * exclusion between two different calls of device_rename
1861 * on the same device to ensure that new_name is valid and
1862 * won't conflict with other devices.
1864 * Note: Don't call this function. Currently, the networking layer calls this
1865 * function, but that will change. The following text from Kay Sievers offers
1868 * Renaming devices is racy at many levels, symlinks and other stuff are not
1869 * replaced atomically, and you get a "move" uevent, but it's not easy to
1870 * connect the event to the old and new device. Device nodes are not renamed at
1871 * all, there isn't even support for that in the kernel now.
1873 * In the meantime, during renaming, your target name might be taken by another
1874 * driver, creating conflicts. Or the old name is taken directly after you
1875 * renamed it -- then you get events for the same DEVPATH, before you even see
1876 * the "move" event. It's just a mess, and nothing new should ever rely on
1877 * kernel device renaming. Besides that, it's not even implemented now for
1878 * other things than (driver-core wise very simple) network devices.
1880 * We are currently about to change network renaming in udev to completely
1881 * disallow renaming of devices in the same namespace as the kernel uses,
1882 * because we can't solve the problems properly, that arise with swapping names
1883 * of multiple interfaces without races. Means, renaming of eth[0-9]* will only
1884 * be allowed to some other name than eth[0-9]*, for the aforementioned
1887 * Make up a "real" name in the driver before you register anything, or add
1888 * some other attributes for userspace to find the device, or use udev to add
1889 * symlinks -- but never rename kernel devices later, it's a complete mess. We
1890 * don't even want to get into that and try to implement the missing pieces in
1891 * the core. We really have other pieces to fix in the driver core mess. :)
1893 int device_rename(struct device *dev, const char *new_name)
1895 char *old_device_name = NULL;
1898 dev = get_device(dev);
1902 pr_debug("device: '%s': %s: renaming to '%s'\n", dev_name(dev),
1903 __func__, new_name);
1905 old_device_name = kstrdup(dev_name(dev), GFP_KERNEL);
1906 if (!old_device_name) {
1912 error = sysfs_rename_link(&dev->class->p->subsys.kobj,
1913 &dev->kobj, old_device_name, new_name);
1918 error = kobject_rename(&dev->kobj, new_name);
1925 kfree(old_device_name);
1929 EXPORT_SYMBOL_GPL(device_rename);
1931 static int device_move_class_links(struct device *dev,
1932 struct device *old_parent,
1933 struct device *new_parent)
1938 sysfs_remove_link(&dev->kobj, "device");
1940 error = sysfs_create_link(&dev->kobj, &new_parent->kobj,
1946 * device_move - moves a device to a new parent
1947 * @dev: the pointer to the struct device to be moved
1948 * @new_parent: the new parent of the device (can by NULL)
1949 * @dpm_order: how to reorder the dpm_list
1951 int device_move(struct device *dev, struct device *new_parent,
1952 enum dpm_order dpm_order)
1955 struct device *old_parent;
1956 struct kobject *new_parent_kobj;
1958 dev = get_device(dev);
1963 new_parent = get_device(new_parent);
1964 new_parent_kobj = get_device_parent(dev, new_parent);
1966 pr_debug("device: '%s': %s: moving to '%s'\n", dev_name(dev),
1967 __func__, new_parent ? dev_name(new_parent) : "<NULL>");
1968 error = kobject_move(&dev->kobj, new_parent_kobj);
1970 cleanup_glue_dir(dev, new_parent_kobj);
1971 put_device(new_parent);
1974 old_parent = dev->parent;
1975 dev->parent = new_parent;
1977 klist_remove(&dev->p->knode_parent);
1979 klist_add_tail(&dev->p->knode_parent,
1980 &new_parent->p->klist_children);
1981 set_dev_node(dev, dev_to_node(new_parent));
1985 error = device_move_class_links(dev, old_parent, new_parent);
1987 /* We ignore errors on cleanup since we're hosed anyway... */
1988 device_move_class_links(dev, new_parent, old_parent);
1989 if (!kobject_move(&dev->kobj, &old_parent->kobj)) {
1991 klist_remove(&dev->p->knode_parent);
1992 dev->parent = old_parent;
1994 klist_add_tail(&dev->p->knode_parent,
1995 &old_parent->p->klist_children);
1996 set_dev_node(dev, dev_to_node(old_parent));
1999 cleanup_glue_dir(dev, new_parent_kobj);
2000 put_device(new_parent);
2004 switch (dpm_order) {
2005 case DPM_ORDER_NONE:
2007 case DPM_ORDER_DEV_AFTER_PARENT:
2008 device_pm_move_after(dev, new_parent);
2010 case DPM_ORDER_PARENT_BEFORE_DEV:
2011 device_pm_move_before(new_parent, dev);
2013 case DPM_ORDER_DEV_LAST:
2014 device_pm_move_last(dev);
2018 put_device(old_parent);
2024 EXPORT_SYMBOL_GPL(device_move);
2027 * device_shutdown - call ->shutdown() on each device to shutdown.
2029 void device_shutdown(void)
2033 spin_lock(&devices_kset->list_lock);
2035 * Walk the devices list backward, shutting down each in turn.
2036 * Beware that device unplug events may also start pulling
2037 * devices offline, even as the system is shutting down.
2039 while (!list_empty(&devices_kset->list)) {
2040 dev = list_entry(devices_kset->list.prev, struct device,
2044 * hold reference count of device's parent to
2045 * prevent it from being freed because parent's
2046 * lock is to be held
2048 get_device(dev->parent);
2051 * Make sure the device is off the kset list, in the
2052 * event that dev->*->shutdown() doesn't remove it.
2054 list_del_init(&dev->kobj.entry);
2055 spin_unlock(&devices_kset->list_lock);
2057 /* hold lock to avoid race with probe/release */
2059 device_lock(dev->parent);
2062 /* Don't allow any more runtime suspends */
2063 pm_runtime_get_noresume(dev);
2064 pm_runtime_barrier(dev);
2066 if (dev->bus && dev->bus->shutdown) {
2068 dev_info(dev, "shutdown\n");
2069 dev->bus->shutdown(dev);
2070 } else if (dev->driver && dev->driver->shutdown) {
2072 dev_info(dev, "shutdown\n");
2073 dev->driver->shutdown(dev);
2078 device_unlock(dev->parent);
2081 put_device(dev->parent);
2083 spin_lock(&devices_kset->list_lock);
2085 spin_unlock(&devices_kset->list_lock);
2086 async_synchronize_full();
2090 * Device logging functions
2093 #ifdef CONFIG_PRINTK
2095 create_syslog_header(const struct device *dev, char *hdr, size_t hdrlen)
2101 subsys = dev->class->name;
2103 subsys = dev->bus->name;
2107 pos += snprintf(hdr + pos, hdrlen - pos, "SUBSYSTEM=%s", subsys);
2110 * Add device identifier DEVICE=:
2114 * +sound:card0 subsystem:devname
2116 if (MAJOR(dev->devt)) {
2119 if (strcmp(subsys, "block") == 0)
2124 pos += snprintf(hdr + pos, hdrlen - pos,
2126 c, MAJOR(dev->devt), MINOR(dev->devt));
2127 } else if (strcmp(subsys, "net") == 0) {
2128 struct net_device *net = to_net_dev(dev);
2131 pos += snprintf(hdr + pos, hdrlen - pos,
2132 "DEVICE=n%u", net->ifindex);
2135 pos += snprintf(hdr + pos, hdrlen - pos,
2136 "DEVICE=+%s:%s", subsys, dev_name(dev));
2141 EXPORT_SYMBOL(create_syslog_header);
2143 int dev_vprintk_emit(int level, const struct device *dev,
2144 const char *fmt, va_list args)
2149 hdrlen = create_syslog_header(dev, hdr, sizeof(hdr));
2151 return vprintk_emit(0, level, hdrlen ? hdr : NULL, hdrlen, fmt, args);
2153 EXPORT_SYMBOL(dev_vprintk_emit);
2155 int dev_printk_emit(int level, const struct device *dev, const char *fmt, ...)
2160 va_start(args, fmt);
2162 r = dev_vprintk_emit(level, dev, fmt, args);
2168 EXPORT_SYMBOL(dev_printk_emit);
2170 static int __dev_printk(const char *level, const struct device *dev,
2171 struct va_format *vaf)
2174 return printk("%s(NULL device *): %pV", level, vaf);
2176 return dev_printk_emit(level[1] - '0', dev,
2178 dev_driver_string(dev), dev_name(dev), vaf);
2181 int dev_printk(const char *level, const struct device *dev,
2182 const char *fmt, ...)
2184 struct va_format vaf;
2188 va_start(args, fmt);
2193 r = __dev_printk(level, dev, &vaf);
2199 EXPORT_SYMBOL(dev_printk);
2201 #define define_dev_printk_level(func, kern_level) \
2202 int func(const struct device *dev, const char *fmt, ...) \
2204 struct va_format vaf; \
2208 va_start(args, fmt); \
2213 r = __dev_printk(kern_level, dev, &vaf); \
2219 EXPORT_SYMBOL(func);
2221 define_dev_printk_level(dev_emerg, KERN_EMERG);
2222 define_dev_printk_level(dev_alert, KERN_ALERT);
2223 define_dev_printk_level(dev_crit, KERN_CRIT);
2224 define_dev_printk_level(dev_err, KERN_ERR);
2225 define_dev_printk_level(dev_warn, KERN_WARNING);
2226 define_dev_printk_level(dev_notice, KERN_NOTICE);
2227 define_dev_printk_level(_dev_info, KERN_INFO);