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>
21 #include <linux/genhd.h>
22 #include <asm/semaphore.h>
25 #include "power/power.h"
27 int (*platform_notify
)(struct device
*dev
) = NULL
;
28 int (*platform_notify_remove
)(struct device
*dev
) = NULL
;
31 static inline int device_is_not_partition(struct device
*dev
)
33 return !(dev
->type
== &part_type
);
36 static inline int device_is_not_partition(struct device
*dev
)
43 * dev_driver_string - Return a device's driver name, if at all possible
44 * @dev: struct device to get the name of
46 * Will return the device's driver's name if it is bound to a device. If
47 * the device is not bound to a device, it will return the name of the bus
48 * it is attached to. If it is not attached to a bus either, an empty
49 * string will be returned.
51 const char *dev_driver_string(struct device
*dev
)
53 return dev
->driver
? dev
->driver
->name
:
54 (dev
->bus
? dev
->bus
->name
:
55 (dev
->class ? dev
->class->name
: ""));
57 EXPORT_SYMBOL(dev_driver_string
);
59 #define to_dev(obj) container_of(obj, struct device, kobj)
60 #define to_dev_attr(_attr) container_of(_attr, struct device_attribute, attr)
62 static ssize_t
dev_attr_show(struct kobject
*kobj
, struct attribute
*attr
,
65 struct device_attribute
*dev_attr
= to_dev_attr(attr
);
66 struct device
*dev
= to_dev(kobj
);
70 ret
= dev_attr
->show(dev
, dev_attr
, buf
);
74 static ssize_t
dev_attr_store(struct kobject
*kobj
, struct attribute
*attr
,
75 const char *buf
, size_t count
)
77 struct device_attribute
*dev_attr
= to_dev_attr(attr
);
78 struct device
*dev
= to_dev(kobj
);
82 ret
= dev_attr
->store(dev
, dev_attr
, buf
, count
);
86 static struct sysfs_ops dev_sysfs_ops
= {
87 .show
= dev_attr_show
,
88 .store
= dev_attr_store
,
93 * device_release - free device structure.
94 * @kobj: device's kobject.
96 * This is called once the reference count for the object
97 * reaches 0. We forward the call to the device's release
98 * method, which should handle actually freeing the structure.
100 static void device_release(struct kobject
*kobj
)
102 struct device
*dev
= to_dev(kobj
);
106 else if (dev
->type
&& dev
->type
->release
)
107 dev
->type
->release(dev
);
108 else if (dev
->class && dev
->class->dev_release
)
109 dev
->class->dev_release(dev
);
111 printk(KERN_ERR
"Device '%s' does not have a release() "
112 "function, it is broken and must be fixed.\n",
118 static struct kobj_type device_ktype
= {
119 .release
= device_release
,
120 .sysfs_ops
= &dev_sysfs_ops
,
124 static int dev_uevent_filter(struct kset
*kset
, struct kobject
*kobj
)
126 struct kobj_type
*ktype
= get_ktype(kobj
);
128 if (ktype
== &device_ktype
) {
129 struct device
*dev
= to_dev(kobj
);
130 if (dev
->uevent_suppress
)
140 static const char *dev_uevent_name(struct kset
*kset
, struct kobject
*kobj
)
142 struct device
*dev
= to_dev(kobj
);
145 return dev
->bus
->name
;
147 return dev
->class->name
;
151 static int dev_uevent(struct kset
*kset
, struct kobject
*kobj
,
152 struct kobj_uevent_env
*env
)
154 struct device
*dev
= to_dev(kobj
);
157 /* add the major/minor if present */
158 if (MAJOR(dev
->devt
)) {
159 add_uevent_var(env
, "MAJOR=%u", MAJOR(dev
->devt
));
160 add_uevent_var(env
, "MINOR=%u", MINOR(dev
->devt
));
163 if (dev
->type
&& dev
->type
->name
)
164 add_uevent_var(env
, "DEVTYPE=%s", dev
->type
->name
);
167 add_uevent_var(env
, "DRIVER=%s", dev
->driver
->name
);
169 #ifdef CONFIG_SYSFS_DEPRECATED
171 struct device
*parent
= dev
->parent
;
173 /* find first bus device in parent chain */
174 while (parent
&& !parent
->bus
)
175 parent
= parent
->parent
;
176 if (parent
&& parent
->bus
) {
179 path
= kobject_get_path(&parent
->kobj
, GFP_KERNEL
);
181 add_uevent_var(env
, "PHYSDEVPATH=%s", path
);
185 add_uevent_var(env
, "PHYSDEVBUS=%s", parent
->bus
->name
);
188 add_uevent_var(env
, "PHYSDEVDRIVER=%s",
189 parent
->driver
->name
);
191 } else if (dev
->bus
) {
192 add_uevent_var(env
, "PHYSDEVBUS=%s", dev
->bus
->name
);
195 add_uevent_var(env
, "PHYSDEVDRIVER=%s",
200 /* have the bus specific function add its stuff */
201 if (dev
->bus
&& dev
->bus
->uevent
) {
202 retval
= dev
->bus
->uevent(dev
, env
);
204 pr_debug("device: '%s': %s: bus uevent() returned %d\n",
205 dev
->bus_id
, __FUNCTION__
, retval
);
208 /* have the class specific function add its stuff */
209 if (dev
->class && dev
->class->dev_uevent
) {
210 retval
= dev
->class->dev_uevent(dev
, env
);
212 pr_debug("device: '%s': %s: class uevent() "
213 "returned %d\n", dev
->bus_id
,
214 __FUNCTION__
, retval
);
217 /* have the device type specific fuction add its stuff */
218 if (dev
->type
&& dev
->type
->uevent
) {
219 retval
= dev
->type
->uevent(dev
, env
);
221 pr_debug("device: '%s': %s: dev_type uevent() "
222 "returned %d\n", dev
->bus_id
,
223 __FUNCTION__
, retval
);
229 static struct kset_uevent_ops device_uevent_ops
= {
230 .filter
= dev_uevent_filter
,
231 .name
= dev_uevent_name
,
232 .uevent
= dev_uevent
,
235 static ssize_t
show_uevent(struct device
*dev
, struct device_attribute
*attr
,
238 struct kobject
*top_kobj
;
240 struct kobj_uevent_env
*env
= NULL
;
245 /* search the kset, the device belongs to */
246 top_kobj
= &dev
->kobj
;
247 while (!top_kobj
->kset
&& top_kobj
->parent
)
248 top_kobj
= top_kobj
->parent
;
252 kset
= top_kobj
->kset
;
253 if (!kset
->uevent_ops
|| !kset
->uevent_ops
->uevent
)
257 if (kset
->uevent_ops
&& kset
->uevent_ops
->filter
)
258 if (!kset
->uevent_ops
->filter(kset
, &dev
->kobj
))
261 env
= kzalloc(sizeof(struct kobj_uevent_env
), GFP_KERNEL
);
265 /* let the kset specific function add its keys */
266 retval
= kset
->uevent_ops
->uevent(kset
, &dev
->kobj
, env
);
270 /* copy keys to file */
271 for (i
= 0; i
< env
->envp_idx
; i
++)
272 count
+= sprintf(&buf
[count
], "%s\n", env
->envp
[i
]);
278 static ssize_t
store_uevent(struct device
*dev
, struct device_attribute
*attr
,
279 const char *buf
, size_t count
)
281 enum kobject_action action
;
283 if (kobject_action_type(buf
, count
, &action
) == 0) {
284 kobject_uevent(&dev
->kobj
, action
);
288 dev_err(dev
, "uevent: unsupported action-string; this will "
289 "be ignored in a future kernel version\n");
290 kobject_uevent(&dev
->kobj
, KOBJ_ADD
);
295 static struct device_attribute uevent_attr
=
296 __ATTR(uevent
, S_IRUGO
| S_IWUSR
, show_uevent
, store_uevent
);
298 static int device_add_attributes(struct device
*dev
,
299 struct device_attribute
*attrs
)
305 for (i
= 0; attr_name(attrs
[i
]); i
++) {
306 error
= device_create_file(dev
, &attrs
[i
]);
312 device_remove_file(dev
, &attrs
[i
]);
317 static void device_remove_attributes(struct device
*dev
,
318 struct device_attribute
*attrs
)
323 for (i
= 0; attr_name(attrs
[i
]); i
++)
324 device_remove_file(dev
, &attrs
[i
]);
327 static int device_add_groups(struct device
*dev
,
328 struct attribute_group
**groups
)
334 for (i
= 0; groups
[i
]; i
++) {
335 error
= sysfs_create_group(&dev
->kobj
, groups
[i
]);
338 sysfs_remove_group(&dev
->kobj
,
347 static void device_remove_groups(struct device
*dev
,
348 struct attribute_group
**groups
)
353 for (i
= 0; groups
[i
]; i
++)
354 sysfs_remove_group(&dev
->kobj
, groups
[i
]);
357 static int device_add_attrs(struct device
*dev
)
359 struct class *class = dev
->class;
360 struct device_type
*type
= dev
->type
;
364 error
= device_add_attributes(dev
, class->dev_attrs
);
370 error
= device_add_groups(dev
, type
->groups
);
372 goto err_remove_class_attrs
;
375 error
= device_add_groups(dev
, dev
->groups
);
377 goto err_remove_type_groups
;
381 err_remove_type_groups
:
383 device_remove_groups(dev
, type
->groups
);
384 err_remove_class_attrs
:
386 device_remove_attributes(dev
, class->dev_attrs
);
391 static void device_remove_attrs(struct device
*dev
)
393 struct class *class = dev
->class;
394 struct device_type
*type
= dev
->type
;
396 device_remove_groups(dev
, dev
->groups
);
399 device_remove_groups(dev
, type
->groups
);
402 device_remove_attributes(dev
, class->dev_attrs
);
406 static ssize_t
show_dev(struct device
*dev
, struct device_attribute
*attr
,
409 return print_dev_t(buf
, dev
->devt
);
412 static struct device_attribute devt_attr
=
413 __ATTR(dev
, S_IRUGO
, show_dev
, NULL
);
415 /* kset to create /sys/devices/ */
416 struct kset
*devices_kset
;
419 * device_create_file - create sysfs attribute file for device.
421 * @attr: device attribute descriptor.
423 int device_create_file(struct device
*dev
, struct device_attribute
*attr
)
427 error
= sysfs_create_file(&dev
->kobj
, &attr
->attr
);
432 * device_remove_file - remove sysfs attribute file.
434 * @attr: device attribute descriptor.
436 void device_remove_file(struct device
*dev
, struct device_attribute
*attr
)
439 sysfs_remove_file(&dev
->kobj
, &attr
->attr
);
443 * device_create_bin_file - create sysfs binary attribute file for device.
445 * @attr: device binary attribute descriptor.
447 int device_create_bin_file(struct device
*dev
, struct bin_attribute
*attr
)
451 error
= sysfs_create_bin_file(&dev
->kobj
, attr
);
454 EXPORT_SYMBOL_GPL(device_create_bin_file
);
457 * device_remove_bin_file - remove sysfs binary attribute file
459 * @attr: device binary attribute descriptor.
461 void device_remove_bin_file(struct device
*dev
, struct bin_attribute
*attr
)
464 sysfs_remove_bin_file(&dev
->kobj
, attr
);
466 EXPORT_SYMBOL_GPL(device_remove_bin_file
);
469 * device_schedule_callback_owner - helper to schedule a callback for a device
471 * @func: callback function to invoke later.
472 * @owner: module owning the callback routine
474 * Attribute methods must not unregister themselves or their parent device
475 * (which would amount to the same thing). Attempts to do so will deadlock,
476 * since unregistration is mutually exclusive with driver callbacks.
478 * Instead methods can call this routine, which will attempt to allocate
479 * and schedule a workqueue request to call back @func with @dev as its
480 * argument in the workqueue's process context. @dev will be pinned until
483 * This routine is usually called via the inline device_schedule_callback(),
484 * which automatically sets @owner to THIS_MODULE.
486 * Returns 0 if the request was submitted, -ENOMEM if storage could not
487 * be allocated, -ENODEV if a reference to @owner isn't available.
489 * NOTE: This routine won't work if CONFIG_SYSFS isn't set! It uses an
490 * underlying sysfs routine (since it is intended for use by attribute
491 * methods), and if sysfs isn't available you'll get nothing but -ENOSYS.
493 int device_schedule_callback_owner(struct device
*dev
,
494 void (*func
)(struct device
*), struct module
*owner
)
496 return sysfs_schedule_callback(&dev
->kobj
,
497 (void (*)(void *)) func
, dev
, owner
);
499 EXPORT_SYMBOL_GPL(device_schedule_callback_owner
);
501 static void klist_children_get(struct klist_node
*n
)
503 struct device
*dev
= container_of(n
, struct device
, knode_parent
);
508 static void klist_children_put(struct klist_node
*n
)
510 struct device
*dev
= container_of(n
, struct device
, knode_parent
);
516 * device_initialize - init device structure.
519 * This prepares the device for use by other layers,
520 * including adding it to the device hierarchy.
521 * It is the first half of device_register(), if called by
522 * that, though it can also be called separately, so one
523 * may use @dev's fields (e.g. the refcount).
525 void device_initialize(struct device
*dev
)
527 dev
->kobj
.kset
= devices_kset
;
528 kobject_init(&dev
->kobj
, &device_ktype
);
529 klist_init(&dev
->klist_children
, klist_children_get
,
531 INIT_LIST_HEAD(&dev
->dma_pools
);
532 INIT_LIST_HEAD(&dev
->node
);
533 init_MUTEX(&dev
->sem
);
534 spin_lock_init(&dev
->devres_lock
);
535 INIT_LIST_HEAD(&dev
->devres_head
);
536 device_init_wakeup(dev
, 0);
537 set_dev_node(dev
, -1);
540 #ifdef CONFIG_SYSFS_DEPRECATED
541 static struct kobject
*get_device_parent(struct device
*dev
,
542 struct device
*parent
)
544 /* class devices without a parent live in /sys/class/<classname>/ */
545 if (dev
->class && (!parent
|| parent
->class != dev
->class))
546 return &dev
->class->subsys
.kobj
;
547 /* all other devices keep their parent */
549 return &parent
->kobj
;
554 static inline void cleanup_device_parent(struct device
*dev
) {}
555 static inline void cleanup_glue_dir(struct device
*dev
,
556 struct kobject
*glue_dir
) {}
558 static struct kobject
*virtual_device_parent(struct device
*dev
)
560 static struct kobject
*virtual_dir
= NULL
;
563 virtual_dir
= kobject_create_and_add("virtual",
564 &devices_kset
->kobj
);
569 static struct kobject
*get_device_parent(struct device
*dev
,
570 struct device
*parent
)
575 struct kobject
*kobj
= NULL
;
576 struct kobject
*parent_kobj
;
580 * If we have no parent, we live in "virtual".
581 * Class-devices with a non class-device as parent, live
582 * in a "glue" directory to prevent namespace collisions.
585 parent_kobj
= virtual_device_parent(dev
);
586 else if (parent
->class)
587 return &parent
->kobj
;
589 parent_kobj
= &parent
->kobj
;
591 /* find our class-directory at the parent and reference it */
592 spin_lock(&dev
->class->class_dirs
.list_lock
);
593 list_for_each_entry(k
, &dev
->class->class_dirs
.list
, entry
)
594 if (k
->parent
== parent_kobj
) {
595 kobj
= kobject_get(k
);
598 spin_unlock(&dev
->class->class_dirs
.list_lock
);
602 /* or create a new class-directory at the parent device */
603 k
= kobject_create();
606 k
->kset
= &dev
->class->class_dirs
;
607 retval
= kobject_add(k
, parent_kobj
, "%s", dev
->class->name
);
612 /* do not emit an uevent for this simple "glue" directory */
617 return &parent
->kobj
;
621 static void cleanup_glue_dir(struct device
*dev
, struct kobject
*glue_dir
)
623 /* see if we live in a "glue" directory */
624 <<<<<<< HEAD
:drivers
/base
/core
.c
625 if (!dev
->class || glue_dir
->kset
!= &dev
->class->class_dirs
)
627 if (!glue_dir
|| !dev
->class ||
628 glue_dir
->kset
!= &dev
->class->class_dirs
)
629 >>>>>>> 264e3e889d86e552b4191d69bb60f4f3b383135a
:drivers
/base
/core
.c
632 kobject_put(glue_dir
);
635 static void cleanup_device_parent(struct device
*dev
)
637 cleanup_glue_dir(dev
, dev
->kobj
.parent
);
641 static void setup_parent(struct device
*dev
, struct device
*parent
)
643 struct kobject
*kobj
;
644 kobj
= get_device_parent(dev
, parent
);
646 dev
->kobj
.parent
= kobj
;
649 static int device_add_class_symlinks(struct device
*dev
)
656 error
= sysfs_create_link(&dev
->kobj
, &dev
->class->subsys
.kobj
,
661 #ifdef CONFIG_SYSFS_DEPRECATED
662 /* stacked class devices need a symlink in the class directory */
663 if (dev
->kobj
.parent
!= &dev
->class->subsys
.kobj
&&
664 device_is_not_partition(dev
)) {
665 error
= sysfs_create_link(&dev
->class->subsys
.kobj
, &dev
->kobj
,
671 if (dev
->parent
&& device_is_not_partition(dev
)) {
672 struct device
*parent
= dev
->parent
;
676 * stacked class devices have the 'device' link
677 * pointing to the bus device instead of the parent
679 while (parent
->class && !parent
->bus
&& parent
->parent
)
680 parent
= parent
->parent
;
682 error
= sysfs_create_link(&dev
->kobj
,
688 class_name
= make_class_name(dev
->class->name
,
691 error
= sysfs_create_link(&dev
->parent
->kobj
,
692 &dev
->kobj
, class_name
);
700 if (dev
->parent
&& device_is_not_partition(dev
))
701 sysfs_remove_link(&dev
->kobj
, "device");
703 if (dev
->kobj
.parent
!= &dev
->class->subsys
.kobj
&&
704 device_is_not_partition(dev
))
705 sysfs_remove_link(&dev
->class->subsys
.kobj
, dev
->bus_id
);
707 /* link in the class directory pointing to the device */
708 error
= sysfs_create_link(&dev
->class->subsys
.kobj
, &dev
->kobj
,
713 if (dev
->parent
&& device_is_not_partition(dev
)) {
714 error
= sysfs_create_link(&dev
->kobj
, &dev
->parent
->kobj
,
722 sysfs_remove_link(&dev
->class->subsys
.kobj
, dev
->bus_id
);
726 sysfs_remove_link(&dev
->kobj
, "subsystem");
731 static void device_remove_class_symlinks(struct device
*dev
)
736 #ifdef CONFIG_SYSFS_DEPRECATED
737 if (dev
->parent
&& device_is_not_partition(dev
)) {
740 class_name
= make_class_name(dev
->class->name
, &dev
->kobj
);
742 sysfs_remove_link(&dev
->parent
->kobj
, class_name
);
745 sysfs_remove_link(&dev
->kobj
, "device");
748 if (dev
->kobj
.parent
!= &dev
->class->subsys
.kobj
&&
749 device_is_not_partition(dev
))
750 sysfs_remove_link(&dev
->class->subsys
.kobj
, dev
->bus_id
);
752 if (dev
->parent
&& device_is_not_partition(dev
))
753 sysfs_remove_link(&dev
->kobj
, "device");
755 sysfs_remove_link(&dev
->class->subsys
.kobj
, dev
->bus_id
);
758 sysfs_remove_link(&dev
->kobj
, "subsystem");
762 * device_add - add device to device hierarchy.
765 * This is part 2 of device_register(), though may be called
766 * separately _iff_ device_initialize() has been called separately.
768 * This adds it to the kobject hierarchy via kobject_add(), adds it
769 * to the global and sibling lists for the device, then
770 * adds it to the other relevant subsystems of the driver model.
772 int device_add(struct device
*dev
)
774 struct device
*parent
= NULL
;
775 struct class_interface
*class_intf
;
778 <<<<<<< HEAD
:drivers
/base
/core
.c
779 error
= pm_sleep_lock();
781 dev_warn(dev
, "Suspicious %s during suspend\n", __FUNCTION__
);
787 >>>>>>> 264e3e889d86e552b4191d69bb60f4f3b383135a
:drivers
/base
/core
.c
788 dev
= get_device(dev
);
789 if (!dev
|| !strlen(dev
->bus_id
)) {
791 <<<<<<< HEAD
:drivers
/base
/core
.c
795 >>>>>>> 264e3e889d86e552b4191d69bb60f4f3b383135a
:drivers
/base
/core
.c
798 pr_debug("device: '%s': %s\n", dev
->bus_id
, __FUNCTION__
);
800 parent
= get_device(dev
->parent
);
801 setup_parent(dev
, parent
);
803 /* first, register with generic layer. */
804 error
= kobject_add(&dev
->kobj
, dev
->kobj
.parent
, "%s", dev
->bus_id
);
808 /* notify platform of device entry */
810 platform_notify(dev
);
812 /* notify clients of device entry (new way) */
814 blocking_notifier_call_chain(&dev
->bus
->p
->bus_notifier
,
815 BUS_NOTIFY_ADD_DEVICE
, dev
);
817 error
= device_create_file(dev
, &uevent_attr
);
821 if (MAJOR(dev
->devt
)) {
822 error
= device_create_file(dev
, &devt_attr
);
824 goto ueventattrError
;
827 error
= device_add_class_symlinks(dev
);
830 error
= device_add_attrs(dev
);
833 error
= dpm_sysfs_add(dev
);
837 error
= bus_add_device(dev
);
840 kobject_uevent(&dev
->kobj
, KOBJ_ADD
);
841 bus_attach_device(dev
);
843 klist_add_tail(&dev
->knode_parent
, &parent
->klist_children
);
846 down(&dev
->class->sem
);
847 /* tie the class to the device */
848 list_add_tail(&dev
->node
, &dev
->class->devices
);
850 /* notify any interfaces that the device is here */
851 list_for_each_entry(class_intf
, &dev
->class->interfaces
, node
)
852 if (class_intf
->add_dev
)
853 class_intf
->add_dev(dev
, class_intf
);
854 up(&dev
->class->sem
);
858 <<<<<<< HEAD
:drivers
/base
/core
.c
861 >>>>>>> 264e3e889d86e552b4191d69bb60f4f3b383135a
:drivers
/base
/core
.c
864 device_pm_remove(dev
);
865 <<<<<<< HEAD
:drivers
/base
/core
.c
866 dpm_sysfs_remove(dev
);
868 >>>>>>> 264e3e889d86e552b4191d69bb60f4f3b383135a
:drivers
/base
/core
.c
871 blocking_notifier_call_chain(&dev
->bus
->p
->bus_notifier
,
872 BUS_NOTIFY_DEL_DEVICE
, dev
);
873 device_remove_attrs(dev
);
875 device_remove_class_symlinks(dev
);
877 if (MAJOR(dev
->devt
))
878 device_remove_file(dev
, &devt_attr
);
880 device_remove_file(dev
, &uevent_attr
);
882 kobject_uevent(&dev
->kobj
, KOBJ_REMOVE
);
883 kobject_del(&dev
->kobj
);
885 cleanup_device_parent(dev
);
892 * device_register - register a device with the system.
893 * @dev: pointer to the device structure
895 * This happens in two clean steps - initialize the device
896 * and add it to the system. The two steps can be called
897 * separately, but this is the easiest and most common.
898 * I.e. you should only call the two helpers separately if
899 * have a clearly defined need to use and refcount the device
900 * before it is added to the hierarchy.
902 int device_register(struct device
*dev
)
904 device_initialize(dev
);
905 return device_add(dev
);
909 * get_device - increment reference count for device.
912 * This simply forwards the call to kobject_get(), though
913 * we do take care to provide for the case that we get a NULL
916 struct device
*get_device(struct device
*dev
)
918 return dev
? to_dev(kobject_get(&dev
->kobj
)) : NULL
;
922 * put_device - decrement reference count.
923 * @dev: device in question.
925 void put_device(struct device
*dev
)
929 kobject_put(&dev
->kobj
);
933 * device_del - delete device from system.
936 * This is the first part of the device unregistration
937 * sequence. This removes the device from the lists we control
938 * from here, has it removed from the other driver model
939 * subsystems it was added to in device_add(), and removes it
940 * from the kobject hierarchy.
942 * NOTE: this should be called manually _iff_ device_add() was
943 * also called manually.
945 void device_del(struct device
*dev
)
947 struct device
*parent
= dev
->parent
;
948 struct class_interface
*class_intf
;
950 device_pm_remove(dev
);
952 klist_del(&dev
->knode_parent
);
953 if (MAJOR(dev
->devt
))
954 device_remove_file(dev
, &devt_attr
);
956 device_remove_class_symlinks(dev
);
958 down(&dev
->class->sem
);
959 /* notify any interfaces that the device is now gone */
960 list_for_each_entry(class_intf
, &dev
->class->interfaces
, node
)
961 if (class_intf
->remove_dev
)
962 class_intf
->remove_dev(dev
, class_intf
);
963 /* remove the device from the class list */
964 list_del_init(&dev
->node
);
965 up(&dev
->class->sem
);
967 device_remove_file(dev
, &uevent_attr
);
968 device_remove_attrs(dev
);
969 bus_remove_device(dev
);
972 * Some platform devices are driven without driver attached
973 * and managed resources may have been acquired. Make sure
974 * all resources are released.
976 devres_release_all(dev
);
978 /* Notify the platform of the removal, in case they
979 * need to do anything...
981 if (platform_notify_remove
)
982 platform_notify_remove(dev
);
984 blocking_notifier_call_chain(&dev
->bus
->p
->bus_notifier
,
985 BUS_NOTIFY_DEL_DEVICE
, dev
);
986 kobject_uevent(&dev
->kobj
, KOBJ_REMOVE
);
987 cleanup_device_parent(dev
);
988 kobject_del(&dev
->kobj
);
993 * device_unregister - unregister device from system.
994 * @dev: device going away.
996 * We do this in two parts, like we do device_register(). First,
997 * we remove it from all the subsystems with device_del(), then
998 * we decrement the reference count via put_device(). If that
999 * is the final reference count, the device will be cleaned up
1000 * via device_release() above. Otherwise, the structure will
1001 * stick around until the final reference to the device is dropped.
1003 void device_unregister(struct device
*dev
)
1005 pr_debug("device: '%s': %s\n", dev
->bus_id
, __FUNCTION__
);
1010 static struct device
*next_device(struct klist_iter
*i
)
1012 struct klist_node
*n
= klist_next(i
);
1013 return n
? container_of(n
, struct device
, knode_parent
) : NULL
;
1017 * device_for_each_child - device child iterator.
1018 * @parent: parent struct device.
1019 * @data: data for the callback.
1020 * @fn: function to be called for each device.
1022 * Iterate over @parent's child devices, and call @fn for each,
1025 * We check the return of @fn each time. If it returns anything
1026 * other than 0, we break out and return that value.
1028 int device_for_each_child(struct device
*parent
, void *data
,
1029 int (*fn
)(struct device
*dev
, void *data
))
1031 struct klist_iter i
;
1032 struct device
*child
;
1035 klist_iter_init(&parent
->klist_children
, &i
);
1036 while ((child
= next_device(&i
)) && !error
)
1037 error
= fn(child
, data
);
1038 klist_iter_exit(&i
);
1043 * device_find_child - device iterator for locating a particular device.
1044 * @parent: parent struct device
1045 * @data: Data to pass to match function
1046 * @match: Callback function to check device
1048 * This is similar to the device_for_each_child() function above, but it
1049 * returns a reference to a device that is 'found' for later use, as
1050 * determined by the @match callback.
1052 * The callback should return 0 if the device doesn't match and non-zero
1053 * if it does. If the callback returns non-zero and a reference to the
1054 * current device can be obtained, this function will return to the caller
1055 * and not iterate over any more devices.
1057 struct device
*device_find_child(struct device
*parent
, void *data
,
1058 int (*match
)(struct device
*dev
, void *data
))
1060 struct klist_iter i
;
1061 struct device
*child
;
1066 klist_iter_init(&parent
->klist_children
, &i
);
1067 while ((child
= next_device(&i
)))
1068 if (match(child
, data
) && get_device(child
))
1070 klist_iter_exit(&i
);
1074 int __init
devices_init(void)
1076 devices_kset
= kset_create_and_add("devices", &device_uevent_ops
, NULL
);
1082 EXPORT_SYMBOL_GPL(device_for_each_child
);
1083 EXPORT_SYMBOL_GPL(device_find_child
);
1085 EXPORT_SYMBOL_GPL(device_initialize
);
1086 EXPORT_SYMBOL_GPL(device_add
);
1087 EXPORT_SYMBOL_GPL(device_register
);
1089 EXPORT_SYMBOL_GPL(device_del
);
1090 EXPORT_SYMBOL_GPL(device_unregister
);
1091 EXPORT_SYMBOL_GPL(get_device
);
1092 EXPORT_SYMBOL_GPL(put_device
);
1094 EXPORT_SYMBOL_GPL(device_create_file
);
1095 EXPORT_SYMBOL_GPL(device_remove_file
);
1098 static void device_create_release(struct device
*dev
)
1100 pr_debug("device: '%s': %s\n", dev
->bus_id
, __FUNCTION__
);
1105 * device_create - creates a device and registers it with sysfs
1106 * @class: pointer to the struct class that this device should be registered to
1107 * @parent: pointer to the parent struct device of this new device, if any
1108 * @devt: the dev_t for the char device to be added
1109 * @fmt: string for the device's name
1111 * This function can be used by char device classes. A struct device
1112 * will be created in sysfs, registered to the specified class.
1114 * A "dev" file will be created, showing the dev_t for the device, if
1115 * the dev_t is not 0,0.
1116 * If a pointer to a parent struct device is passed in, the newly created
1117 * struct device will be a child of that device in sysfs.
1118 * The pointer to the struct device will be returned from the call.
1119 * Any further sysfs files that might be required can be created using this
1122 * Note: the struct class passed to this function must have previously
1123 * been created with a call to class_create().
1125 struct device
*device_create(struct class *class, struct device
*parent
,
1126 dev_t devt
, const char *fmt
, ...)
1129 struct device
*dev
= NULL
;
1130 int retval
= -ENODEV
;
1132 if (class == NULL
|| IS_ERR(class))
1135 dev
= kzalloc(sizeof(*dev
), GFP_KERNEL
);
1143 dev
->parent
= parent
;
1144 dev
->release
= device_create_release
;
1146 va_start(args
, fmt
);
1147 vsnprintf(dev
->bus_id
, BUS_ID_SIZE
, fmt
, args
);
1149 retval
= device_register(dev
);
1157 return ERR_PTR(retval
);
1159 EXPORT_SYMBOL_GPL(device_create
);
1161 static int __match_devt(struct device
*dev
, void *data
)
1165 return dev
->devt
== *devt
;
1169 * device_destroy - removes a device that was created with device_create()
1170 * @class: pointer to the struct class that this device was registered with
1171 * @devt: the dev_t of the device that was previously registered
1173 * This call unregisters and cleans up a device that was created with a
1174 * call to device_create().
1176 void device_destroy(struct class *class, dev_t devt
)
1180 dev
= class_find_device(class, &devt
, __match_devt
);
1183 device_unregister(dev
);
1186 EXPORT_SYMBOL_GPL(device_destroy
);
1188 #ifdef CONFIG_PM_SLEEP
1190 * destroy_suspended_device - asks the PM core to remove a suspended device
1191 * @class: pointer to the struct class that this device was registered with
1192 * @devt: the dev_t of the device that was previously registered
1194 * This call notifies the PM core of the necessity to unregister a suspended
1195 * device created with a call to device_create() (devices cannot be
1196 * unregistered directly while suspended, since the PM core holds their
1197 * semaphores at that time).
1199 * It can only be called within the scope of a system sleep transition. In
1200 * practice this means it has to be directly or indirectly invoked either by
1201 * a suspend or resume method, or by the PM core (e.g. via
1202 * disable_nonboot_cpus() or enable_nonboot_cpus()).
1204 void destroy_suspended_device(struct class *class, dev_t devt
)
1208 dev
= class_find_device(class, &devt
, __match_devt
);
1210 device_pm_schedule_removal(dev
);
1214 EXPORT_SYMBOL_GPL(destroy_suspended_device
);
1215 #endif /* CONFIG_PM_SLEEP */
1218 * device_rename - renames a device
1219 * @dev: the pointer to the struct device to be renamed
1220 * @new_name: the new name of the device
1222 int device_rename(struct device
*dev
, char *new_name
)
1224 char *old_class_name
= NULL
;
1225 char *new_class_name
= NULL
;
1226 char *old_device_name
= NULL
;
1229 dev
= get_device(dev
);
1233 pr_debug("device: '%s': %s: renaming to '%s'\n", dev
->bus_id
,
1234 __FUNCTION__
, new_name
);
1236 #ifdef CONFIG_SYSFS_DEPRECATED
1237 if ((dev
->class) && (dev
->parent
))
1238 old_class_name
= make_class_name(dev
->class->name
, &dev
->kobj
);
1241 old_device_name
= kmalloc(BUS_ID_SIZE
, GFP_KERNEL
);
1242 if (!old_device_name
) {
1246 strlcpy(old_device_name
, dev
->bus_id
, BUS_ID_SIZE
);
1247 strlcpy(dev
->bus_id
, new_name
, BUS_ID_SIZE
);
1249 error
= kobject_rename(&dev
->kobj
, new_name
);
1251 strlcpy(dev
->bus_id
, old_device_name
, BUS_ID_SIZE
);
1255 #ifdef CONFIG_SYSFS_DEPRECATED
1256 if (old_class_name
) {
1257 new_class_name
= make_class_name(dev
->class->name
, &dev
->kobj
);
1258 if (new_class_name
) {
1259 error
= sysfs_create_link(&dev
->parent
->kobj
,
1260 &dev
->kobj
, new_class_name
);
1263 sysfs_remove_link(&dev
->parent
->kobj
, old_class_name
);
1268 sysfs_remove_link(&dev
->class->subsys
.kobj
, old_device_name
);
1269 error
= sysfs_create_link(&dev
->class->subsys
.kobj
, &dev
->kobj
,
1272 dev_err(dev
, "%s: sysfs_create_symlink failed (%d)\n",
1273 __FUNCTION__
, error
);
1281 kfree(new_class_name
);
1282 kfree(old_class_name
);
1283 kfree(old_device_name
);
1287 EXPORT_SYMBOL_GPL(device_rename
);
1289 static int device_move_class_links(struct device
*dev
,
1290 struct device
*old_parent
,
1291 struct device
*new_parent
)
1294 #ifdef CONFIG_SYSFS_DEPRECATED
1297 class_name
= make_class_name(dev
->class->name
, &dev
->kobj
);
1303 sysfs_remove_link(&dev
->kobj
, "device");
1304 sysfs_remove_link(&old_parent
->kobj
, class_name
);
1307 error
= sysfs_create_link(&dev
->kobj
, &new_parent
->kobj
,
1311 error
= sysfs_create_link(&new_parent
->kobj
, &dev
->kobj
,
1314 sysfs_remove_link(&dev
->kobj
, "device");
1322 sysfs_remove_link(&dev
->kobj
, "device");
1324 error
= sysfs_create_link(&dev
->kobj
, &new_parent
->kobj
,
1331 * device_move - moves a device to a new parent
1332 * @dev: the pointer to the struct device to be moved
1333 * @new_parent: the new parent of the device (can by NULL)
1335 int device_move(struct device
*dev
, struct device
*new_parent
)
1338 struct device
*old_parent
;
1339 struct kobject
*new_parent_kobj
;
1341 dev
= get_device(dev
);
1345 new_parent
= get_device(new_parent
);
1346 new_parent_kobj
= get_device_parent(dev
, new_parent
);
1348 pr_debug("device: '%s': %s: moving to '%s'\n", dev
->bus_id
,
1349 __FUNCTION__
, new_parent
? new_parent
->bus_id
: "<NULL>");
1350 error
= kobject_move(&dev
->kobj
, new_parent_kobj
);
1352 cleanup_glue_dir(dev
, new_parent_kobj
);
1353 put_device(new_parent
);
1356 old_parent
= dev
->parent
;
1357 dev
->parent
= new_parent
;
1359 klist_remove(&dev
->knode_parent
);
1361 klist_add_tail(&dev
->knode_parent
, &new_parent
->klist_children
);
1364 error
= device_move_class_links(dev
, old_parent
, new_parent
);
1366 /* We ignore errors on cleanup since we're hosed anyway... */
1367 device_move_class_links(dev
, new_parent
, old_parent
);
1368 if (!kobject_move(&dev
->kobj
, &old_parent
->kobj
)) {
1370 klist_remove(&dev
->knode_parent
);
1372 klist_add_tail(&dev
->knode_parent
,
1373 &old_parent
->klist_children
);
1375 cleanup_glue_dir(dev
, new_parent_kobj
);
1376 put_device(new_parent
);
1380 put_device(old_parent
);
1385 EXPORT_SYMBOL_GPL(device_move
);
1388 * device_shutdown - call ->shutdown() on each device to shutdown.
1390 void device_shutdown(void)
1392 struct device
*dev
, *devn
;
1394 list_for_each_entry_safe_reverse(dev
, devn
, &devices_kset
->list
,
1396 if (dev
->bus
&& dev
->bus
->shutdown
) {
1397 dev_dbg(dev
, "shutdown\n");
1398 dev
->bus
->shutdown(dev
);
1399 } else if (dev
->driver
&& dev
->driver
->shutdown
) {
1400 dev_dbg(dev
, "shutdown\n");
1401 dev
->driver
->shutdown(dev
);