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>
29 #include <linux/sysfs.h>
32 #include "power/power.h"
34 #ifdef CONFIG_SYSFS_DEPRECATED
35 #ifdef CONFIG_SYSFS_DEPRECATED_V2
36 long sysfs_deprecated
= 1;
38 long sysfs_deprecated
= 0;
40 static int __init
sysfs_deprecated_setup(char *arg
)
42 return kstrtol(arg
, 10, &sysfs_deprecated
);
44 early_param("sysfs.deprecated", sysfs_deprecated_setup
);
47 int (*platform_notify
)(struct device
*dev
) = NULL
;
48 int (*platform_notify_remove
)(struct device
*dev
) = NULL
;
49 static struct kobject
*dev_kobj
;
50 struct kobject
*sysfs_dev_char_kobj
;
51 struct kobject
*sysfs_dev_block_kobj
;
53 static DEFINE_MUTEX(device_hotplug_lock
);
55 void lock_device_hotplug(void)
57 mutex_lock(&device_hotplug_lock
);
60 void unlock_device_hotplug(void)
62 mutex_unlock(&device_hotplug_lock
);
65 int lock_device_hotplug_sysfs(void)
67 if (mutex_trylock(&device_hotplug_lock
))
70 /* Avoid busy looping (5 ms of sleep should do). */
72 return restart_syscall();
76 static inline int device_is_not_partition(struct device
*dev
)
78 return !(dev
->type
== &part_type
);
81 static inline int device_is_not_partition(struct device
*dev
)
88 * dev_driver_string - Return a device's driver name, if at all possible
89 * @dev: struct device to get the name of
91 * Will return the device's driver's name if it is bound to a device. If
92 * the device is not bound to a driver, it will return the name of the bus
93 * it is attached to. If it is not attached to a bus either, an empty
94 * string will be returned.
96 const char *dev_driver_string(const struct device
*dev
)
98 struct device_driver
*drv
;
100 /* dev->driver can change to NULL underneath us because of unbinding,
101 * so be careful about accessing it. dev->bus and dev->class should
102 * never change once they are set, so they don't need special care.
104 drv
= ACCESS_ONCE(dev
->driver
);
105 return drv
? drv
->name
:
106 (dev
->bus
? dev
->bus
->name
:
107 (dev
->class ? dev
->class->name
: ""));
109 EXPORT_SYMBOL(dev_driver_string
);
111 #define to_dev_attr(_attr) container_of(_attr, struct device_attribute, attr)
113 static ssize_t
dev_attr_show(struct kobject
*kobj
, struct attribute
*attr
,
116 struct device_attribute
*dev_attr
= to_dev_attr(attr
);
117 struct device
*dev
= kobj_to_dev(kobj
);
121 ret
= dev_attr
->show(dev
, dev_attr
, buf
);
122 if (ret
>= (ssize_t
)PAGE_SIZE
) {
123 print_symbol("dev_attr_show: %s returned bad count\n",
124 (unsigned long)dev_attr
->show
);
129 static ssize_t
dev_attr_store(struct kobject
*kobj
, struct attribute
*attr
,
130 const char *buf
, size_t count
)
132 struct device_attribute
*dev_attr
= to_dev_attr(attr
);
133 struct device
*dev
= kobj_to_dev(kobj
);
137 ret
= dev_attr
->store(dev
, dev_attr
, buf
, count
);
141 static const struct sysfs_ops dev_sysfs_ops
= {
142 .show
= dev_attr_show
,
143 .store
= dev_attr_store
,
146 #define to_ext_attr(x) container_of(x, struct dev_ext_attribute, attr)
148 ssize_t
device_store_ulong(struct device
*dev
,
149 struct device_attribute
*attr
,
150 const char *buf
, size_t size
)
152 struct dev_ext_attribute
*ea
= to_ext_attr(attr
);
154 unsigned long new = simple_strtoul(buf
, &end
, 0);
157 *(unsigned long *)(ea
->var
) = new;
158 /* Always return full write size even if we didn't consume all */
161 EXPORT_SYMBOL_GPL(device_store_ulong
);
163 ssize_t
device_show_ulong(struct device
*dev
,
164 struct device_attribute
*attr
,
167 struct dev_ext_attribute
*ea
= to_ext_attr(attr
);
168 return snprintf(buf
, PAGE_SIZE
, "%lx\n", *(unsigned long *)(ea
->var
));
170 EXPORT_SYMBOL_GPL(device_show_ulong
);
172 ssize_t
device_store_int(struct device
*dev
,
173 struct device_attribute
*attr
,
174 const char *buf
, size_t size
)
176 struct dev_ext_attribute
*ea
= to_ext_attr(attr
);
178 long new = simple_strtol(buf
, &end
, 0);
179 if (end
== buf
|| new > INT_MAX
|| new < INT_MIN
)
181 *(int *)(ea
->var
) = new;
182 /* Always return full write size even if we didn't consume all */
185 EXPORT_SYMBOL_GPL(device_store_int
);
187 ssize_t
device_show_int(struct device
*dev
,
188 struct device_attribute
*attr
,
191 struct dev_ext_attribute
*ea
= to_ext_attr(attr
);
193 return snprintf(buf
, PAGE_SIZE
, "%d\n", *(int *)(ea
->var
));
195 EXPORT_SYMBOL_GPL(device_show_int
);
197 ssize_t
device_store_bool(struct device
*dev
, struct device_attribute
*attr
,
198 const char *buf
, size_t size
)
200 struct dev_ext_attribute
*ea
= to_ext_attr(attr
);
202 if (strtobool(buf
, ea
->var
) < 0)
207 EXPORT_SYMBOL_GPL(device_store_bool
);
209 ssize_t
device_show_bool(struct device
*dev
, struct device_attribute
*attr
,
212 struct dev_ext_attribute
*ea
= to_ext_attr(attr
);
214 return snprintf(buf
, PAGE_SIZE
, "%d\n", *(bool *)(ea
->var
));
216 EXPORT_SYMBOL_GPL(device_show_bool
);
219 * device_release - free device structure.
220 * @kobj: device's kobject.
222 * This is called once the reference count for the object
223 * reaches 0. We forward the call to the device's release
224 * method, which should handle actually freeing the structure.
226 static void device_release(struct kobject
*kobj
)
228 struct device
*dev
= kobj_to_dev(kobj
);
229 struct device_private
*p
= dev
->p
;
232 * Some platform devices are driven without driver attached
233 * and managed resources may have been acquired. Make sure
234 * all resources are released.
236 * Drivers still can add resources into device after device
237 * is deleted but alive, so release devres here to avoid
238 * possible memory leak.
240 devres_release_all(dev
);
244 else if (dev
->type
&& dev
->type
->release
)
245 dev
->type
->release(dev
);
246 else if (dev
->class && dev
->class->dev_release
)
247 dev
->class->dev_release(dev
);
249 WARN(1, KERN_ERR
"Device '%s' does not have a release() "
250 "function, it is broken and must be fixed.\n",
255 static const void *device_namespace(struct kobject
*kobj
)
257 struct device
*dev
= kobj_to_dev(kobj
);
258 const void *ns
= NULL
;
260 if (dev
->class && dev
->class->ns_type
)
261 ns
= dev
->class->namespace(dev
);
266 static struct kobj_type device_ktype
= {
267 .release
= device_release
,
268 .sysfs_ops
= &dev_sysfs_ops
,
269 .namespace = device_namespace
,
273 static int dev_uevent_filter(struct kset
*kset
, struct kobject
*kobj
)
275 struct kobj_type
*ktype
= get_ktype(kobj
);
277 if (ktype
== &device_ktype
) {
278 struct device
*dev
= kobj_to_dev(kobj
);
287 static const char *dev_uevent_name(struct kset
*kset
, struct kobject
*kobj
)
289 struct device
*dev
= kobj_to_dev(kobj
);
292 return dev
->bus
->name
;
294 return dev
->class->name
;
298 static int dev_uevent(struct kset
*kset
, struct kobject
*kobj
,
299 struct kobj_uevent_env
*env
)
301 struct device
*dev
= kobj_to_dev(kobj
);
304 /* add device node properties if present */
305 if (MAJOR(dev
->devt
)) {
309 kuid_t uid
= GLOBAL_ROOT_UID
;
310 kgid_t gid
= GLOBAL_ROOT_GID
;
312 add_uevent_var(env
, "MAJOR=%u", MAJOR(dev
->devt
));
313 add_uevent_var(env
, "MINOR=%u", MINOR(dev
->devt
));
314 name
= device_get_devnode(dev
, &mode
, &uid
, &gid
, &tmp
);
316 add_uevent_var(env
, "DEVNAME=%s", name
);
318 add_uevent_var(env
, "DEVMODE=%#o", mode
& 0777);
319 if (!uid_eq(uid
, GLOBAL_ROOT_UID
))
320 add_uevent_var(env
, "DEVUID=%u", from_kuid(&init_user_ns
, uid
));
321 if (!gid_eq(gid
, GLOBAL_ROOT_GID
))
322 add_uevent_var(env
, "DEVGID=%u", from_kgid(&init_user_ns
, gid
));
327 if (dev
->type
&& dev
->type
->name
)
328 add_uevent_var(env
, "DEVTYPE=%s", dev
->type
->name
);
331 add_uevent_var(env
, "DRIVER=%s", dev
->driver
->name
);
333 /* Add common DT information about the device */
334 of_device_uevent(dev
, env
);
336 /* have the bus specific function add its stuff */
337 if (dev
->bus
&& dev
->bus
->uevent
) {
338 retval
= dev
->bus
->uevent(dev
, env
);
340 pr_debug("device: '%s': %s: bus uevent() returned %d\n",
341 dev_name(dev
), __func__
, retval
);
344 /* have the class specific function add its stuff */
345 if (dev
->class && dev
->class->dev_uevent
) {
346 retval
= dev
->class->dev_uevent(dev
, env
);
348 pr_debug("device: '%s': %s: class uevent() "
349 "returned %d\n", dev_name(dev
),
353 /* have the device type specific function add its stuff */
354 if (dev
->type
&& dev
->type
->uevent
) {
355 retval
= dev
->type
->uevent(dev
, env
);
357 pr_debug("device: '%s': %s: dev_type uevent() "
358 "returned %d\n", dev_name(dev
),
365 static const struct kset_uevent_ops device_uevent_ops
= {
366 .filter
= dev_uevent_filter
,
367 .name
= dev_uevent_name
,
368 .uevent
= dev_uevent
,
371 static ssize_t
uevent_show(struct device
*dev
, struct device_attribute
*attr
,
374 struct kobject
*top_kobj
;
376 struct kobj_uevent_env
*env
= NULL
;
381 /* search the kset, the device belongs to */
382 top_kobj
= &dev
->kobj
;
383 while (!top_kobj
->kset
&& top_kobj
->parent
)
384 top_kobj
= top_kobj
->parent
;
388 kset
= top_kobj
->kset
;
389 if (!kset
->uevent_ops
|| !kset
->uevent_ops
->uevent
)
393 if (kset
->uevent_ops
&& kset
->uevent_ops
->filter
)
394 if (!kset
->uevent_ops
->filter(kset
, &dev
->kobj
))
397 env
= kzalloc(sizeof(struct kobj_uevent_env
), GFP_KERNEL
);
401 /* let the kset specific function add its keys */
402 retval
= kset
->uevent_ops
->uevent(kset
, &dev
->kobj
, env
);
406 /* copy keys to file */
407 for (i
= 0; i
< env
->envp_idx
; i
++)
408 count
+= sprintf(&buf
[count
], "%s\n", env
->envp
[i
]);
414 static ssize_t
uevent_store(struct device
*dev
, struct device_attribute
*attr
,
415 const char *buf
, size_t count
)
417 enum kobject_action action
;
419 if (kobject_action_type(buf
, count
, &action
) == 0)
420 kobject_uevent(&dev
->kobj
, action
);
422 dev_err(dev
, "uevent: unknown action-string\n");
425 static DEVICE_ATTR_RW(uevent
);
427 static ssize_t
online_show(struct device
*dev
, struct device_attribute
*attr
,
435 return sprintf(buf
, "%u\n", val
);
438 static ssize_t
online_store(struct device
*dev
, struct device_attribute
*attr
,
439 const char *buf
, size_t count
)
444 ret
= strtobool(buf
, &val
);
448 ret
= lock_device_hotplug_sysfs();
452 ret
= val
? device_online(dev
) : device_offline(dev
);
453 unlock_device_hotplug();
454 return ret
< 0 ? ret
: count
;
456 static DEVICE_ATTR_RW(online
);
458 int device_add_groups(struct device
*dev
, const struct attribute_group
**groups
)
460 return sysfs_create_groups(&dev
->kobj
, groups
);
463 void device_remove_groups(struct device
*dev
,
464 const struct attribute_group
**groups
)
466 sysfs_remove_groups(&dev
->kobj
, groups
);
469 static int device_add_attrs(struct device
*dev
)
471 struct class *class = dev
->class;
472 const struct device_type
*type
= dev
->type
;
476 error
= device_add_groups(dev
, class->dev_groups
);
482 error
= device_add_groups(dev
, type
->groups
);
484 goto err_remove_class_groups
;
487 error
= device_add_groups(dev
, dev
->groups
);
489 goto err_remove_type_groups
;
491 if (device_supports_offline(dev
) && !dev
->offline_disabled
) {
492 error
= device_create_file(dev
, &dev_attr_online
);
494 goto err_remove_dev_groups
;
499 err_remove_dev_groups
:
500 device_remove_groups(dev
, dev
->groups
);
501 err_remove_type_groups
:
503 device_remove_groups(dev
, type
->groups
);
504 err_remove_class_groups
:
506 device_remove_groups(dev
, class->dev_groups
);
511 static void device_remove_attrs(struct device
*dev
)
513 struct class *class = dev
->class;
514 const struct device_type
*type
= dev
->type
;
516 device_remove_file(dev
, &dev_attr_online
);
517 device_remove_groups(dev
, dev
->groups
);
520 device_remove_groups(dev
, type
->groups
);
523 device_remove_groups(dev
, class->dev_groups
);
526 static ssize_t
dev_show(struct device
*dev
, struct device_attribute
*attr
,
529 return print_dev_t(buf
, dev
->devt
);
531 static DEVICE_ATTR_RO(dev
);
534 struct kset
*devices_kset
;
537 * device_create_file - create sysfs attribute file for device.
539 * @attr: device attribute descriptor.
541 int device_create_file(struct device
*dev
,
542 const struct device_attribute
*attr
)
547 WARN(((attr
->attr
.mode
& S_IWUGO
) && !attr
->store
),
548 "Attribute %s: write permission without 'store'\n",
550 WARN(((attr
->attr
.mode
& S_IRUGO
) && !attr
->show
),
551 "Attribute %s: read permission without 'show'\n",
553 error
= sysfs_create_file(&dev
->kobj
, &attr
->attr
);
558 EXPORT_SYMBOL_GPL(device_create_file
);
561 * device_remove_file - remove sysfs attribute file.
563 * @attr: device attribute descriptor.
565 void device_remove_file(struct device
*dev
,
566 const struct device_attribute
*attr
)
569 sysfs_remove_file(&dev
->kobj
, &attr
->attr
);
571 EXPORT_SYMBOL_GPL(device_remove_file
);
574 * device_remove_file_self - remove sysfs attribute file from its own method.
576 * @attr: device attribute descriptor.
578 * See kernfs_remove_self() for details.
580 bool device_remove_file_self(struct device
*dev
,
581 const struct device_attribute
*attr
)
584 return sysfs_remove_file_self(&dev
->kobj
, &attr
->attr
);
588 EXPORT_SYMBOL_GPL(device_remove_file_self
);
591 * device_create_bin_file - create sysfs binary attribute file for device.
593 * @attr: device binary attribute descriptor.
595 int device_create_bin_file(struct device
*dev
,
596 const struct bin_attribute
*attr
)
600 error
= sysfs_create_bin_file(&dev
->kobj
, attr
);
603 EXPORT_SYMBOL_GPL(device_create_bin_file
);
606 * device_remove_bin_file - remove sysfs binary attribute file
608 * @attr: device binary attribute descriptor.
610 void device_remove_bin_file(struct device
*dev
,
611 const struct bin_attribute
*attr
)
614 sysfs_remove_bin_file(&dev
->kobj
, attr
);
616 EXPORT_SYMBOL_GPL(device_remove_bin_file
);
618 static void klist_children_get(struct klist_node
*n
)
620 struct device_private
*p
= to_device_private_parent(n
);
621 struct device
*dev
= p
->device
;
626 static void klist_children_put(struct klist_node
*n
)
628 struct device_private
*p
= to_device_private_parent(n
);
629 struct device
*dev
= p
->device
;
635 * device_initialize - init device structure.
638 * This prepares the device for use by other layers by initializing
640 * It is the first half of device_register(), if called by
641 * that function, though it can also be called separately, so one
642 * may use @dev's fields. In particular, get_device()/put_device()
643 * may be used for reference counting of @dev after calling this
646 * All fields in @dev must be initialized by the caller to 0, except
647 * for those explicitly set to some other value. The simplest
648 * approach is to use kzalloc() to allocate the structure containing
651 * NOTE: Use put_device() to give up your reference instead of freeing
652 * @dev directly once you have called this function.
654 void device_initialize(struct device
*dev
)
656 dev
->kobj
.kset
= devices_kset
;
657 kobject_init(&dev
->kobj
, &device_ktype
);
658 INIT_LIST_HEAD(&dev
->dma_pools
);
659 mutex_init(&dev
->mutex
);
660 lockdep_set_novalidate_class(&dev
->mutex
);
661 spin_lock_init(&dev
->devres_lock
);
662 INIT_LIST_HEAD(&dev
->devres_head
);
664 set_dev_node(dev
, -1);
666 EXPORT_SYMBOL_GPL(device_initialize
);
668 struct kobject
*virtual_device_parent(struct device
*dev
)
670 static struct kobject
*virtual_dir
= NULL
;
673 virtual_dir
= kobject_create_and_add("virtual",
674 &devices_kset
->kobj
);
684 #define to_class_dir(obj) container_of(obj, struct class_dir, kobj)
686 static void class_dir_release(struct kobject
*kobj
)
688 struct class_dir
*dir
= to_class_dir(kobj
);
693 struct kobj_ns_type_operations
*class_dir_child_ns_type(struct kobject
*kobj
)
695 struct class_dir
*dir
= to_class_dir(kobj
);
696 return dir
->class->ns_type
;
699 static struct kobj_type class_dir_ktype
= {
700 .release
= class_dir_release
,
701 .sysfs_ops
= &kobj_sysfs_ops
,
702 .child_ns_type
= class_dir_child_ns_type
705 static struct kobject
*
706 class_dir_create_and_add(struct class *class, struct kobject
*parent_kobj
)
708 struct class_dir
*dir
;
711 dir
= kzalloc(sizeof(*dir
), GFP_KERNEL
);
716 kobject_init(&dir
->kobj
, &class_dir_ktype
);
718 dir
->kobj
.kset
= &class->p
->glue_dirs
;
720 retval
= kobject_add(&dir
->kobj
, parent_kobj
, "%s", class->name
);
722 kobject_put(&dir
->kobj
);
729 static struct kobject
*get_device_parent(struct device
*dev
,
730 struct device
*parent
)
733 static DEFINE_MUTEX(gdp_mutex
);
734 struct kobject
*kobj
= NULL
;
735 struct kobject
*parent_kobj
;
739 /* block disks show up in /sys/block */
740 if (sysfs_deprecated
&& dev
->class == &block_class
) {
741 if (parent
&& parent
->class == &block_class
)
742 return &parent
->kobj
;
743 return &block_class
.p
->subsys
.kobj
;
748 * If we have no parent, we live in "virtual".
749 * Class-devices with a non class-device as parent, live
750 * in a "glue" directory to prevent namespace collisions.
753 parent_kobj
= virtual_device_parent(dev
);
754 else if (parent
->class && !dev
->class->ns_type
)
755 return &parent
->kobj
;
757 parent_kobj
= &parent
->kobj
;
759 mutex_lock(&gdp_mutex
);
761 /* find our class-directory at the parent and reference it */
762 spin_lock(&dev
->class->p
->glue_dirs
.list_lock
);
763 list_for_each_entry(k
, &dev
->class->p
->glue_dirs
.list
, entry
)
764 if (k
->parent
== parent_kobj
) {
765 kobj
= kobject_get(k
);
768 spin_unlock(&dev
->class->p
->glue_dirs
.list_lock
);
770 mutex_unlock(&gdp_mutex
);
774 /* or create a new class-directory at the parent device */
775 k
= class_dir_create_and_add(dev
->class, parent_kobj
);
776 /* do not emit an uevent for this simple "glue" directory */
777 mutex_unlock(&gdp_mutex
);
781 /* subsystems can specify a default root directory for their devices */
782 if (!parent
&& dev
->bus
&& dev
->bus
->dev_root
)
783 return &dev
->bus
->dev_root
->kobj
;
786 return &parent
->kobj
;
790 static void cleanup_glue_dir(struct device
*dev
, struct kobject
*glue_dir
)
792 /* see if we live in a "glue" directory */
793 if (!glue_dir
|| !dev
->class ||
794 glue_dir
->kset
!= &dev
->class->p
->glue_dirs
)
797 kobject_put(glue_dir
);
800 static void cleanup_device_parent(struct device
*dev
)
802 cleanup_glue_dir(dev
, dev
->kobj
.parent
);
805 static int device_add_class_symlinks(struct device
*dev
)
812 error
= sysfs_create_link(&dev
->kobj
,
813 &dev
->class->p
->subsys
.kobj
,
818 if (dev
->parent
&& device_is_not_partition(dev
)) {
819 error
= sysfs_create_link(&dev
->kobj
, &dev
->parent
->kobj
,
826 /* /sys/block has directories and does not need symlinks */
827 if (sysfs_deprecated
&& dev
->class == &block_class
)
831 /* link in the class directory pointing to the device */
832 error
= sysfs_create_link(&dev
->class->p
->subsys
.kobj
,
833 &dev
->kobj
, dev_name(dev
));
840 sysfs_remove_link(&dev
->kobj
, "device");
843 sysfs_remove_link(&dev
->kobj
, "subsystem");
848 static void device_remove_class_symlinks(struct device
*dev
)
853 if (dev
->parent
&& device_is_not_partition(dev
))
854 sysfs_remove_link(&dev
->kobj
, "device");
855 sysfs_remove_link(&dev
->kobj
, "subsystem");
857 if (sysfs_deprecated
&& dev
->class == &block_class
)
860 sysfs_delete_link(&dev
->class->p
->subsys
.kobj
, &dev
->kobj
, dev_name(dev
));
864 * dev_set_name - set a device name
866 * @fmt: format string for the device's name
868 int dev_set_name(struct device
*dev
, const char *fmt
, ...)
873 va_start(vargs
, fmt
);
874 err
= kobject_set_name_vargs(&dev
->kobj
, fmt
, vargs
);
878 EXPORT_SYMBOL_GPL(dev_set_name
);
881 * device_to_dev_kobj - select a /sys/dev/ directory for the device
884 * By default we select char/ for new entries. Setting class->dev_obj
885 * to NULL prevents an entry from being created. class->dev_kobj must
886 * be set (or cleared) before any devices are registered to the class
887 * otherwise device_create_sys_dev_entry() and
888 * device_remove_sys_dev_entry() will disagree about the presence of
891 static struct kobject
*device_to_dev_kobj(struct device
*dev
)
893 struct kobject
*kobj
;
896 kobj
= dev
->class->dev_kobj
;
898 kobj
= sysfs_dev_char_kobj
;
903 static int device_create_sys_dev_entry(struct device
*dev
)
905 struct kobject
*kobj
= device_to_dev_kobj(dev
);
910 format_dev_t(devt_str
, dev
->devt
);
911 error
= sysfs_create_link(kobj
, &dev
->kobj
, devt_str
);
917 static void device_remove_sys_dev_entry(struct device
*dev
)
919 struct kobject
*kobj
= device_to_dev_kobj(dev
);
923 format_dev_t(devt_str
, dev
->devt
);
924 sysfs_remove_link(kobj
, devt_str
);
928 int device_private_init(struct device
*dev
)
930 dev
->p
= kzalloc(sizeof(*dev
->p
), GFP_KERNEL
);
933 dev
->p
->device
= dev
;
934 klist_init(&dev
->p
->klist_children
, klist_children_get
,
936 INIT_LIST_HEAD(&dev
->p
->deferred_probe
);
941 * device_add - add device to device hierarchy.
944 * This is part 2 of device_register(), though may be called
945 * separately _iff_ device_initialize() has been called separately.
947 * This adds @dev to the kobject hierarchy via kobject_add(), adds it
948 * to the global and sibling lists for the device, then
949 * adds it to the other relevant subsystems of the driver model.
951 * Do not call this routine or device_register() more than once for
952 * any device structure. The driver model core is not designed to work
953 * with devices that get unregistered and then spring back to life.
954 * (Among other things, it's very hard to guarantee that all references
955 * to the previous incarnation of @dev have been dropped.) Allocate
956 * and register a fresh new struct device instead.
958 * NOTE: _Never_ directly free @dev after calling this function, even
959 * if it returned an error! Always use put_device() to give up your
962 int device_add(struct device
*dev
)
964 struct device
*parent
= NULL
;
965 struct kobject
*kobj
;
966 struct class_interface
*class_intf
;
969 dev
= get_device(dev
);
974 error
= device_private_init(dev
);
980 * for statically allocated devices, which should all be converted
981 * some day, we need to initialize the name. We prevent reading back
982 * the name, and force the use of dev_name()
984 if (dev
->init_name
) {
985 dev_set_name(dev
, "%s", dev
->init_name
);
986 dev
->init_name
= NULL
;
989 /* subsystems can specify simple device enumeration */
990 if (!dev_name(dev
) && dev
->bus
&& dev
->bus
->dev_name
)
991 dev_set_name(dev
, "%s%u", dev
->bus
->dev_name
, dev
->id
);
993 if (!dev_name(dev
)) {
998 pr_debug("device: '%s': %s\n", dev_name(dev
), __func__
);
1000 parent
= get_device(dev
->parent
);
1001 kobj
= get_device_parent(dev
, parent
);
1003 dev
->kobj
.parent
= kobj
;
1005 /* use parent numa_node */
1007 set_dev_node(dev
, dev_to_node(parent
));
1009 /* first, register with generic layer. */
1010 /* we require the name to be set before, and pass NULL */
1011 error
= kobject_add(&dev
->kobj
, dev
->kobj
.parent
, NULL
);
1015 /* notify platform of device entry */
1016 if (platform_notify
)
1017 platform_notify(dev
);
1019 error
= device_create_file(dev
, &dev_attr_uevent
);
1023 if (MAJOR(dev
->devt
)) {
1024 error
= device_create_file(dev
, &dev_attr_dev
);
1026 goto ueventattrError
;
1028 error
= device_create_sys_dev_entry(dev
);
1032 devtmpfs_create_node(dev
);
1035 error
= device_add_class_symlinks(dev
);
1038 error
= device_add_attrs(dev
);
1041 error
= bus_add_device(dev
);
1044 error
= dpm_sysfs_add(dev
);
1049 /* Notify clients of device addition. This call must come
1050 * after dpm_sysfs_add() and before kobject_uevent().
1053 blocking_notifier_call_chain(&dev
->bus
->p
->bus_notifier
,
1054 BUS_NOTIFY_ADD_DEVICE
, dev
);
1056 kobject_uevent(&dev
->kobj
, KOBJ_ADD
);
1057 bus_probe_device(dev
);
1059 klist_add_tail(&dev
->p
->knode_parent
,
1060 &parent
->p
->klist_children
);
1063 mutex_lock(&dev
->class->p
->mutex
);
1064 /* tie the class to the device */
1065 klist_add_tail(&dev
->knode_class
,
1066 &dev
->class->p
->klist_devices
);
1068 /* notify any interfaces that the device is here */
1069 list_for_each_entry(class_intf
,
1070 &dev
->class->p
->interfaces
, node
)
1071 if (class_intf
->add_dev
)
1072 class_intf
->add_dev(dev
, class_intf
);
1073 mutex_unlock(&dev
->class->p
->mutex
);
1079 bus_remove_device(dev
);
1081 device_remove_attrs(dev
);
1083 device_remove_class_symlinks(dev
);
1085 if (MAJOR(dev
->devt
))
1086 devtmpfs_delete_node(dev
);
1087 if (MAJOR(dev
->devt
))
1088 device_remove_sys_dev_entry(dev
);
1090 if (MAJOR(dev
->devt
))
1091 device_remove_file(dev
, &dev_attr_dev
);
1093 device_remove_file(dev
, &dev_attr_uevent
);
1095 kobject_uevent(&dev
->kobj
, KOBJ_REMOVE
);
1096 kobject_del(&dev
->kobj
);
1098 cleanup_device_parent(dev
);
1106 EXPORT_SYMBOL_GPL(device_add
);
1109 * device_register - register a device with the system.
1110 * @dev: pointer to the device structure
1112 * This happens in two clean steps - initialize the device
1113 * and add it to the system. The two steps can be called
1114 * separately, but this is the easiest and most common.
1115 * I.e. you should only call the two helpers separately if
1116 * have a clearly defined need to use and refcount the device
1117 * before it is added to the hierarchy.
1119 * For more information, see the kerneldoc for device_initialize()
1122 * NOTE: _Never_ directly free @dev after calling this function, even
1123 * if it returned an error! Always use put_device() to give up the
1124 * reference initialized in this function instead.
1126 int device_register(struct device
*dev
)
1128 device_initialize(dev
);
1129 return device_add(dev
);
1131 EXPORT_SYMBOL_GPL(device_register
);
1134 * get_device - increment reference count for device.
1137 * This simply forwards the call to kobject_get(), though
1138 * we do take care to provide for the case that we get a NULL
1139 * pointer passed in.
1141 struct device
*get_device(struct device
*dev
)
1143 return dev
? kobj_to_dev(kobject_get(&dev
->kobj
)) : NULL
;
1145 EXPORT_SYMBOL_GPL(get_device
);
1148 * put_device - decrement reference count.
1149 * @dev: device in question.
1151 void put_device(struct device
*dev
)
1153 /* might_sleep(); */
1155 kobject_put(&dev
->kobj
);
1157 EXPORT_SYMBOL_GPL(put_device
);
1160 * device_del - delete device from system.
1163 * This is the first part of the device unregistration
1164 * sequence. This removes the device from the lists we control
1165 * from here, has it removed from the other driver model
1166 * subsystems it was added to in device_add(), and removes it
1167 * from the kobject hierarchy.
1169 * NOTE: this should be called manually _iff_ device_add() was
1170 * also called manually.
1172 void device_del(struct device
*dev
)
1174 struct device
*parent
= dev
->parent
;
1175 struct class_interface
*class_intf
;
1177 /* Notify clients of device removal. This call must come
1178 * before dpm_sysfs_remove().
1181 blocking_notifier_call_chain(&dev
->bus
->p
->bus_notifier
,
1182 BUS_NOTIFY_DEL_DEVICE
, dev
);
1183 dpm_sysfs_remove(dev
);
1185 klist_del(&dev
->p
->knode_parent
);
1186 if (MAJOR(dev
->devt
)) {
1187 devtmpfs_delete_node(dev
);
1188 device_remove_sys_dev_entry(dev
);
1189 device_remove_file(dev
, &dev_attr_dev
);
1192 device_remove_class_symlinks(dev
);
1194 mutex_lock(&dev
->class->p
->mutex
);
1195 /* notify any interfaces that the device is now gone */
1196 list_for_each_entry(class_intf
,
1197 &dev
->class->p
->interfaces
, node
)
1198 if (class_intf
->remove_dev
)
1199 class_intf
->remove_dev(dev
, class_intf
);
1200 /* remove the device from the class list */
1201 klist_del(&dev
->knode_class
);
1202 mutex_unlock(&dev
->class->p
->mutex
);
1204 device_remove_file(dev
, &dev_attr_uevent
);
1205 device_remove_attrs(dev
);
1206 bus_remove_device(dev
);
1207 device_pm_remove(dev
);
1208 driver_deferred_probe_del(dev
);
1210 /* Notify the platform of the removal, in case they
1211 * need to do anything...
1213 if (platform_notify_remove
)
1214 platform_notify_remove(dev
);
1215 kobject_uevent(&dev
->kobj
, KOBJ_REMOVE
);
1216 cleanup_device_parent(dev
);
1217 kobject_del(&dev
->kobj
);
1220 EXPORT_SYMBOL_GPL(device_del
);
1223 * device_unregister - unregister device from system.
1224 * @dev: device going away.
1226 * We do this in two parts, like we do device_register(). First,
1227 * we remove it from all the subsystems with device_del(), then
1228 * we decrement the reference count via put_device(). If that
1229 * is the final reference count, the device will be cleaned up
1230 * via device_release() above. Otherwise, the structure will
1231 * stick around until the final reference to the device is dropped.
1233 void device_unregister(struct device
*dev
)
1235 pr_debug("device: '%s': %s\n", dev_name(dev
), __func__
);
1239 EXPORT_SYMBOL_GPL(device_unregister
);
1241 static struct device
*next_device(struct klist_iter
*i
)
1243 struct klist_node
*n
= klist_next(i
);
1244 struct device
*dev
= NULL
;
1245 struct device_private
*p
;
1248 p
= to_device_private_parent(n
);
1255 * device_get_devnode - path of device node file
1257 * @mode: returned file access mode
1258 * @uid: returned file owner
1259 * @gid: returned file group
1260 * @tmp: possibly allocated string
1262 * Return the relative path of a possible device node.
1263 * Non-default names may need to allocate a memory to compose
1264 * a name. This memory is returned in tmp and needs to be
1265 * freed by the caller.
1267 const char *device_get_devnode(struct device
*dev
,
1268 umode_t
*mode
, kuid_t
*uid
, kgid_t
*gid
,
1275 /* the device type may provide a specific name */
1276 if (dev
->type
&& dev
->type
->devnode
)
1277 *tmp
= dev
->type
->devnode(dev
, mode
, uid
, gid
);
1281 /* the class may provide a specific name */
1282 if (dev
->class && dev
->class->devnode
)
1283 *tmp
= dev
->class->devnode(dev
, mode
);
1287 /* return name without allocation, tmp == NULL */
1288 if (strchr(dev_name(dev
), '!') == NULL
)
1289 return dev_name(dev
);
1291 /* replace '!' in the name with '/' */
1292 *tmp
= kstrdup(dev_name(dev
), GFP_KERNEL
);
1295 while ((s
= strchr(*tmp
, '!')))
1301 * device_for_each_child - device child iterator.
1302 * @parent: parent struct device.
1303 * @fn: function to be called for each device.
1304 * @data: data for the callback.
1306 * Iterate over @parent's child devices, and call @fn for each,
1309 * We check the return of @fn each time. If it returns anything
1310 * other than 0, we break out and return that value.
1312 int device_for_each_child(struct device
*parent
, void *data
,
1313 int (*fn
)(struct device
*dev
, void *data
))
1315 struct klist_iter i
;
1316 struct device
*child
;
1322 klist_iter_init(&parent
->p
->klist_children
, &i
);
1323 while ((child
= next_device(&i
)) && !error
)
1324 error
= fn(child
, data
);
1325 klist_iter_exit(&i
);
1328 EXPORT_SYMBOL_GPL(device_for_each_child
);
1331 * device_find_child - device iterator for locating a particular device.
1332 * @parent: parent struct device
1333 * @match: Callback function to check device
1334 * @data: Data to pass to match function
1336 * This is similar to the device_for_each_child() function above, but it
1337 * returns a reference to a device that is 'found' for later use, as
1338 * determined by the @match callback.
1340 * The callback should return 0 if the device doesn't match and non-zero
1341 * if it does. If the callback returns non-zero and a reference to the
1342 * current device can be obtained, this function will return to the caller
1343 * and not iterate over any more devices.
1345 * NOTE: you will need to drop the reference with put_device() after use.
1347 struct device
*device_find_child(struct device
*parent
, void *data
,
1348 int (*match
)(struct device
*dev
, void *data
))
1350 struct klist_iter i
;
1351 struct device
*child
;
1356 klist_iter_init(&parent
->p
->klist_children
, &i
);
1357 while ((child
= next_device(&i
)))
1358 if (match(child
, data
) && get_device(child
))
1360 klist_iter_exit(&i
);
1363 EXPORT_SYMBOL_GPL(device_find_child
);
1365 int __init
devices_init(void)
1367 devices_kset
= kset_create_and_add("devices", &device_uevent_ops
, NULL
);
1370 dev_kobj
= kobject_create_and_add("dev", NULL
);
1373 sysfs_dev_block_kobj
= kobject_create_and_add("block", dev_kobj
);
1374 if (!sysfs_dev_block_kobj
)
1375 goto block_kobj_err
;
1376 sysfs_dev_char_kobj
= kobject_create_and_add("char", dev_kobj
);
1377 if (!sysfs_dev_char_kobj
)
1383 kobject_put(sysfs_dev_block_kobj
);
1385 kobject_put(dev_kobj
);
1387 kset_unregister(devices_kset
);
1391 static int device_check_offline(struct device
*dev
, void *not_used
)
1395 ret
= device_for_each_child(dev
, NULL
, device_check_offline
);
1399 return device_supports_offline(dev
) && !dev
->offline
? -EBUSY
: 0;
1403 * device_offline - Prepare the device for hot-removal.
1404 * @dev: Device to be put offline.
1406 * Execute the device bus type's .offline() callback, if present, to prepare
1407 * the device for a subsequent hot-removal. If that succeeds, the device must
1408 * not be used until either it is removed or its bus type's .online() callback
1411 * Call under device_hotplug_lock.
1413 int device_offline(struct device
*dev
)
1417 if (dev
->offline_disabled
)
1420 ret
= device_for_each_child(dev
, NULL
, device_check_offline
);
1425 if (device_supports_offline(dev
)) {
1429 ret
= dev
->bus
->offline(dev
);
1431 kobject_uevent(&dev
->kobj
, KOBJ_OFFLINE
);
1432 dev
->offline
= true;
1442 * device_online - Put the device back online after successful device_offline().
1443 * @dev: Device to be put back online.
1445 * If device_offline() has been successfully executed for @dev, but the device
1446 * has not been removed subsequently, execute its bus type's .online() callback
1447 * to indicate that the device can be used again.
1449 * Call under device_hotplug_lock.
1451 int device_online(struct device
*dev
)
1456 if (device_supports_offline(dev
)) {
1458 ret
= dev
->bus
->online(dev
);
1460 kobject_uevent(&dev
->kobj
, KOBJ_ONLINE
);
1461 dev
->offline
= false;
1472 struct root_device
{
1474 struct module
*owner
;
1477 static inline struct root_device
*to_root_device(struct device
*d
)
1479 return container_of(d
, struct root_device
, dev
);
1482 static void root_device_release(struct device
*dev
)
1484 kfree(to_root_device(dev
));
1488 * __root_device_register - allocate and register a root device
1489 * @name: root device name
1490 * @owner: owner module of the root device, usually THIS_MODULE
1492 * This function allocates a root device and registers it
1493 * using device_register(). In order to free the returned
1494 * device, use root_device_unregister().
1496 * Root devices are dummy devices which allow other devices
1497 * to be grouped under /sys/devices. Use this function to
1498 * allocate a root device and then use it as the parent of
1499 * any device which should appear under /sys/devices/{name}
1501 * The /sys/devices/{name} directory will also contain a
1502 * 'module' symlink which points to the @owner directory
1505 * Returns &struct device pointer on success, or ERR_PTR() on error.
1507 * Note: You probably want to use root_device_register().
1509 struct device
*__root_device_register(const char *name
, struct module
*owner
)
1511 struct root_device
*root
;
1514 root
= kzalloc(sizeof(struct root_device
), GFP_KERNEL
);
1516 return ERR_PTR(err
);
1518 err
= dev_set_name(&root
->dev
, "%s", name
);
1521 return ERR_PTR(err
);
1524 root
->dev
.release
= root_device_release
;
1526 err
= device_register(&root
->dev
);
1528 put_device(&root
->dev
);
1529 return ERR_PTR(err
);
1532 #ifdef CONFIG_MODULES /* gotta find a "cleaner" way to do this */
1534 struct module_kobject
*mk
= &owner
->mkobj
;
1536 err
= sysfs_create_link(&root
->dev
.kobj
, &mk
->kobj
, "module");
1538 device_unregister(&root
->dev
);
1539 return ERR_PTR(err
);
1541 root
->owner
= owner
;
1547 EXPORT_SYMBOL_GPL(__root_device_register
);
1550 * root_device_unregister - unregister and free a root device
1551 * @dev: device going away
1553 * This function unregisters and cleans up a device that was created by
1554 * root_device_register().
1556 void root_device_unregister(struct device
*dev
)
1558 struct root_device
*root
= to_root_device(dev
);
1561 sysfs_remove_link(&root
->dev
.kobj
, "module");
1563 device_unregister(dev
);
1565 EXPORT_SYMBOL_GPL(root_device_unregister
);
1568 static void device_create_release(struct device
*dev
)
1570 pr_debug("device: '%s': %s\n", dev_name(dev
), __func__
);
1574 static struct device
*
1575 device_create_groups_vargs(struct class *class, struct device
*parent
,
1576 dev_t devt
, void *drvdata
,
1577 const struct attribute_group
**groups
,
1578 const char *fmt
, va_list args
)
1580 struct device
*dev
= NULL
;
1581 int retval
= -ENODEV
;
1583 if (class == NULL
|| IS_ERR(class))
1586 dev
= kzalloc(sizeof(*dev
), GFP_KERNEL
);
1592 device_initialize(dev
);
1595 dev
->parent
= parent
;
1596 dev
->groups
= groups
;
1597 dev
->release
= device_create_release
;
1598 dev_set_drvdata(dev
, drvdata
);
1600 retval
= kobject_set_name_vargs(&dev
->kobj
, fmt
, args
);
1604 retval
= device_add(dev
);
1612 return ERR_PTR(retval
);
1616 * device_create_vargs - creates a device and registers it with sysfs
1617 * @class: pointer to the struct class that this device should be registered to
1618 * @parent: pointer to the parent struct device of this new device, if any
1619 * @devt: the dev_t for the char device to be added
1620 * @drvdata: the data to be added to the device for callbacks
1621 * @fmt: string for the device's name
1622 * @args: va_list for the device's name
1624 * This function can be used by char device classes. A struct device
1625 * will be created in sysfs, registered to the specified class.
1627 * A "dev" file will be created, showing the dev_t for the device, if
1628 * the dev_t is not 0,0.
1629 * If a pointer to a parent struct device is passed in, the newly created
1630 * struct device will be a child of that device in sysfs.
1631 * The pointer to the struct device will be returned from the call.
1632 * Any further sysfs files that might be required can be created using this
1635 * Returns &struct device pointer on success, or ERR_PTR() on error.
1637 * Note: the struct class passed to this function must have previously
1638 * been created with a call to class_create().
1640 struct device
*device_create_vargs(struct class *class, struct device
*parent
,
1641 dev_t devt
, void *drvdata
, const char *fmt
,
1644 return device_create_groups_vargs(class, parent
, devt
, drvdata
, NULL
,
1647 EXPORT_SYMBOL_GPL(device_create_vargs
);
1650 * device_create - creates a device and registers it with sysfs
1651 * @class: pointer to the struct class that this device should be registered to
1652 * @parent: pointer to the parent struct device of this new device, if any
1653 * @devt: the dev_t for the char device to be added
1654 * @drvdata: the data to be added to the device for callbacks
1655 * @fmt: string for the device's name
1657 * This function can be used by char device classes. A struct device
1658 * will be created in sysfs, registered to the specified class.
1660 * A "dev" file will be created, showing the dev_t for the device, if
1661 * the dev_t is not 0,0.
1662 * If a pointer to a parent struct device is passed in, the newly created
1663 * struct device will be a child of that device in sysfs.
1664 * The pointer to the struct device will be returned from the call.
1665 * Any further sysfs files that might be required can be created using this
1668 * Returns &struct device pointer on success, or ERR_PTR() on error.
1670 * Note: the struct class passed to this function must have previously
1671 * been created with a call to class_create().
1673 struct device
*device_create(struct class *class, struct device
*parent
,
1674 dev_t devt
, void *drvdata
, const char *fmt
, ...)
1679 va_start(vargs
, fmt
);
1680 dev
= device_create_vargs(class, parent
, devt
, drvdata
, fmt
, vargs
);
1684 EXPORT_SYMBOL_GPL(device_create
);
1687 * device_create_with_groups - creates a device and registers it with sysfs
1688 * @class: pointer to the struct class that this device should be registered to
1689 * @parent: pointer to the parent struct device of this new device, if any
1690 * @devt: the dev_t for the char device to be added
1691 * @drvdata: the data to be added to the device for callbacks
1692 * @groups: NULL-terminated list of attribute groups to be created
1693 * @fmt: string for the device's name
1695 * This function can be used by char device classes. A struct device
1696 * will be created in sysfs, registered to the specified class.
1697 * Additional attributes specified in the groups parameter will also
1698 * be created automatically.
1700 * A "dev" file will be created, showing the dev_t for the device, if
1701 * the dev_t is not 0,0.
1702 * If a pointer to a parent struct device is passed in, the newly created
1703 * struct device will be a child of that device in sysfs.
1704 * The pointer to the struct device will be returned from the call.
1705 * Any further sysfs files that might be required can be created using this
1708 * Returns &struct device pointer on success, or ERR_PTR() on error.
1710 * Note: the struct class passed to this function must have previously
1711 * been created with a call to class_create().
1713 struct device
*device_create_with_groups(struct class *class,
1714 struct device
*parent
, dev_t devt
,
1716 const struct attribute_group
**groups
,
1717 const char *fmt
, ...)
1722 va_start(vargs
, fmt
);
1723 dev
= device_create_groups_vargs(class, parent
, devt
, drvdata
, groups
,
1728 EXPORT_SYMBOL_GPL(device_create_with_groups
);
1730 static int __match_devt(struct device
*dev
, const void *data
)
1732 const dev_t
*devt
= data
;
1734 return dev
->devt
== *devt
;
1738 * device_destroy - removes a device that was created with device_create()
1739 * @class: pointer to the struct class that this device was registered with
1740 * @devt: the dev_t of the device that was previously registered
1742 * This call unregisters and cleans up a device that was created with a
1743 * call to device_create().
1745 void device_destroy(struct class *class, dev_t devt
)
1749 dev
= class_find_device(class, NULL
, &devt
, __match_devt
);
1752 device_unregister(dev
);
1755 EXPORT_SYMBOL_GPL(device_destroy
);
1758 * device_rename - renames a device
1759 * @dev: the pointer to the struct device to be renamed
1760 * @new_name: the new name of the device
1762 * It is the responsibility of the caller to provide mutual
1763 * exclusion between two different calls of device_rename
1764 * on the same device to ensure that new_name is valid and
1765 * won't conflict with other devices.
1767 * Note: Don't call this function. Currently, the networking layer calls this
1768 * function, but that will change. The following text from Kay Sievers offers
1771 * Renaming devices is racy at many levels, symlinks and other stuff are not
1772 * replaced atomically, and you get a "move" uevent, but it's not easy to
1773 * connect the event to the old and new device. Device nodes are not renamed at
1774 * all, there isn't even support for that in the kernel now.
1776 * In the meantime, during renaming, your target name might be taken by another
1777 * driver, creating conflicts. Or the old name is taken directly after you
1778 * renamed it -- then you get events for the same DEVPATH, before you even see
1779 * the "move" event. It's just a mess, and nothing new should ever rely on
1780 * kernel device renaming. Besides that, it's not even implemented now for
1781 * other things than (driver-core wise very simple) network devices.
1783 * We are currently about to change network renaming in udev to completely
1784 * disallow renaming of devices in the same namespace as the kernel uses,
1785 * because we can't solve the problems properly, that arise with swapping names
1786 * of multiple interfaces without races. Means, renaming of eth[0-9]* will only
1787 * be allowed to some other name than eth[0-9]*, for the aforementioned
1790 * Make up a "real" name in the driver before you register anything, or add
1791 * some other attributes for userspace to find the device, or use udev to add
1792 * symlinks -- but never rename kernel devices later, it's a complete mess. We
1793 * don't even want to get into that and try to implement the missing pieces in
1794 * the core. We really have other pieces to fix in the driver core mess. :)
1796 int device_rename(struct device
*dev
, const char *new_name
)
1798 struct kobject
*kobj
= &dev
->kobj
;
1799 char *old_device_name
= NULL
;
1802 dev
= get_device(dev
);
1806 dev_dbg(dev
, "renaming to %s\n", new_name
);
1808 old_device_name
= kstrdup(dev_name(dev
), GFP_KERNEL
);
1809 if (!old_device_name
) {
1815 error
= sysfs_rename_link_ns(&dev
->class->p
->subsys
.kobj
,
1816 kobj
, old_device_name
,
1817 new_name
, kobject_namespace(kobj
));
1822 error
= kobject_rename(kobj
, new_name
);
1829 kfree(old_device_name
);
1833 EXPORT_SYMBOL_GPL(device_rename
);
1835 static int device_move_class_links(struct device
*dev
,
1836 struct device
*old_parent
,
1837 struct device
*new_parent
)
1842 sysfs_remove_link(&dev
->kobj
, "device");
1844 error
= sysfs_create_link(&dev
->kobj
, &new_parent
->kobj
,
1850 * device_move - moves a device to a new parent
1851 * @dev: the pointer to the struct device to be moved
1852 * @new_parent: the new parent of the device (can by NULL)
1853 * @dpm_order: how to reorder the dpm_list
1855 int device_move(struct device
*dev
, struct device
*new_parent
,
1856 enum dpm_order dpm_order
)
1859 struct device
*old_parent
;
1860 struct kobject
*new_parent_kobj
;
1862 dev
= get_device(dev
);
1867 new_parent
= get_device(new_parent
);
1868 new_parent_kobj
= get_device_parent(dev
, new_parent
);
1870 pr_debug("device: '%s': %s: moving to '%s'\n", dev_name(dev
),
1871 __func__
, new_parent
? dev_name(new_parent
) : "<NULL>");
1872 error
= kobject_move(&dev
->kobj
, new_parent_kobj
);
1874 cleanup_glue_dir(dev
, new_parent_kobj
);
1875 put_device(new_parent
);
1878 old_parent
= dev
->parent
;
1879 dev
->parent
= new_parent
;
1881 klist_remove(&dev
->p
->knode_parent
);
1883 klist_add_tail(&dev
->p
->knode_parent
,
1884 &new_parent
->p
->klist_children
);
1885 set_dev_node(dev
, dev_to_node(new_parent
));
1889 error
= device_move_class_links(dev
, old_parent
, new_parent
);
1891 /* We ignore errors on cleanup since we're hosed anyway... */
1892 device_move_class_links(dev
, new_parent
, old_parent
);
1893 if (!kobject_move(&dev
->kobj
, &old_parent
->kobj
)) {
1895 klist_remove(&dev
->p
->knode_parent
);
1896 dev
->parent
= old_parent
;
1898 klist_add_tail(&dev
->p
->knode_parent
,
1899 &old_parent
->p
->klist_children
);
1900 set_dev_node(dev
, dev_to_node(old_parent
));
1903 cleanup_glue_dir(dev
, new_parent_kobj
);
1904 put_device(new_parent
);
1908 switch (dpm_order
) {
1909 case DPM_ORDER_NONE
:
1911 case DPM_ORDER_DEV_AFTER_PARENT
:
1912 device_pm_move_after(dev
, new_parent
);
1914 case DPM_ORDER_PARENT_BEFORE_DEV
:
1915 device_pm_move_before(new_parent
, dev
);
1917 case DPM_ORDER_DEV_LAST
:
1918 device_pm_move_last(dev
);
1922 put_device(old_parent
);
1928 EXPORT_SYMBOL_GPL(device_move
);
1931 * device_shutdown - call ->shutdown() on each device to shutdown.
1933 void device_shutdown(void)
1935 struct device
*dev
, *parent
;
1937 spin_lock(&devices_kset
->list_lock
);
1939 * Walk the devices list backward, shutting down each in turn.
1940 * Beware that device unplug events may also start pulling
1941 * devices offline, even as the system is shutting down.
1943 while (!list_empty(&devices_kset
->list
)) {
1944 dev
= list_entry(devices_kset
->list
.prev
, struct device
,
1948 * hold reference count of device's parent to
1949 * prevent it from being freed because parent's
1950 * lock is to be held
1952 parent
= get_device(dev
->parent
);
1955 * Make sure the device is off the kset list, in the
1956 * event that dev->*->shutdown() doesn't remove it.
1958 list_del_init(&dev
->kobj
.entry
);
1959 spin_unlock(&devices_kset
->list_lock
);
1961 /* hold lock to avoid race with probe/release */
1963 device_lock(parent
);
1966 /* Don't allow any more runtime suspends */
1967 pm_runtime_get_noresume(dev
);
1968 pm_runtime_barrier(dev
);
1970 if (dev
->bus
&& dev
->bus
->shutdown
) {
1972 dev_info(dev
, "shutdown\n");
1973 dev
->bus
->shutdown(dev
);
1974 } else if (dev
->driver
&& dev
->driver
->shutdown
) {
1976 dev_info(dev
, "shutdown\n");
1977 dev
->driver
->shutdown(dev
);
1982 device_unlock(parent
);
1987 spin_lock(&devices_kset
->list_lock
);
1989 spin_unlock(&devices_kset
->list_lock
);
1990 async_synchronize_full();
1994 * Device logging functions
1997 #ifdef CONFIG_PRINTK
1999 create_syslog_header(const struct device
*dev
, char *hdr
, size_t hdrlen
)
2005 subsys
= dev
->class->name
;
2007 subsys
= dev
->bus
->name
;
2011 pos
+= snprintf(hdr
+ pos
, hdrlen
- pos
, "SUBSYSTEM=%s", subsys
);
2014 * Add device identifier DEVICE=:
2018 * +sound:card0 subsystem:devname
2020 if (MAJOR(dev
->devt
)) {
2023 if (strcmp(subsys
, "block") == 0)
2028 pos
+= snprintf(hdr
+ pos
, hdrlen
- pos
,
2030 c
, MAJOR(dev
->devt
), MINOR(dev
->devt
));
2031 } else if (strcmp(subsys
, "net") == 0) {
2032 struct net_device
*net
= to_net_dev(dev
);
2035 pos
+= snprintf(hdr
+ pos
, hdrlen
- pos
,
2036 "DEVICE=n%u", net
->ifindex
);
2039 pos
+= snprintf(hdr
+ pos
, hdrlen
- pos
,
2040 "DEVICE=+%s:%s", subsys
, dev_name(dev
));
2045 EXPORT_SYMBOL(create_syslog_header
);
2047 int dev_vprintk_emit(int level
, const struct device
*dev
,
2048 const char *fmt
, va_list args
)
2053 hdrlen
= create_syslog_header(dev
, hdr
, sizeof(hdr
));
2055 return vprintk_emit(0, level
, hdrlen
? hdr
: NULL
, hdrlen
, fmt
, args
);
2057 EXPORT_SYMBOL(dev_vprintk_emit
);
2059 int dev_printk_emit(int level
, const struct device
*dev
, const char *fmt
, ...)
2064 va_start(args
, fmt
);
2066 r
= dev_vprintk_emit(level
, dev
, fmt
, args
);
2072 EXPORT_SYMBOL(dev_printk_emit
);
2074 static int __dev_printk(const char *level
, const struct device
*dev
,
2075 struct va_format
*vaf
)
2078 return printk("%s(NULL device *): %pV", level
, vaf
);
2080 return dev_printk_emit(level
[1] - '0', dev
,
2082 dev_driver_string(dev
), dev_name(dev
), vaf
);
2085 int dev_printk(const char *level
, const struct device
*dev
,
2086 const char *fmt
, ...)
2088 struct va_format vaf
;
2092 va_start(args
, fmt
);
2097 r
= __dev_printk(level
, dev
, &vaf
);
2103 EXPORT_SYMBOL(dev_printk
);
2105 #define define_dev_printk_level(func, kern_level) \
2106 int func(const struct device *dev, const char *fmt, ...) \
2108 struct va_format vaf; \
2112 va_start(args, fmt); \
2117 r = __dev_printk(kern_level, dev, &vaf); \
2123 EXPORT_SYMBOL(func);
2125 define_dev_printk_level(dev_emerg
, KERN_EMERG
);
2126 define_dev_printk_level(dev_alert
, KERN_ALERT
);
2127 define_dev_printk_level(dev_crit
, KERN_CRIT
);
2128 define_dev_printk_level(dev_err
, KERN_ERR
);
2129 define_dev_printk_level(dev_warn
, KERN_WARNING
);
2130 define_dev_printk_level(dev_notice
, KERN_NOTICE
);
2131 define_dev_printk_level(_dev_info
, KERN_INFO
);