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 * sysfs bindings for devices.
35 * dev_driver_string - Return a device's driver name, if at all possible
36 * @dev: struct device to get the name of
38 * Will return the device's driver's name if it is bound to a device. If
39 * the device is not bound to a device, it will return the name of the bus
40 * it is attached to. If it is not attached to a bus either, an empty
41 * string will be returned.
43 const char *dev_driver_string(struct device
*dev
)
45 return dev
->driver
? dev
->driver
->name
:
46 (dev
->bus
? dev
->bus
->name
:
47 (dev
->class ? dev
->class->name
: ""));
49 EXPORT_SYMBOL(dev_driver_string
);
51 #define to_dev(obj) container_of(obj, struct device, kobj)
52 #define to_dev_attr(_attr) container_of(_attr, struct device_attribute, attr)
55 dev_attr_show(struct kobject
* kobj
, struct attribute
* attr
, char * buf
)
57 struct device_attribute
* dev_attr
= to_dev_attr(attr
);
58 struct device
* dev
= to_dev(kobj
);
62 ret
= dev_attr
->show(dev
, dev_attr
, buf
);
67 dev_attr_store(struct kobject
* kobj
, struct attribute
* attr
,
68 const char * buf
, size_t count
)
70 struct device_attribute
* dev_attr
= to_dev_attr(attr
);
71 struct device
* dev
= to_dev(kobj
);
75 ret
= dev_attr
->store(dev
, dev_attr
, buf
, count
);
79 static struct sysfs_ops dev_sysfs_ops
= {
80 .show
= dev_attr_show
,
81 .store
= dev_attr_store
,
86 * device_release - free device structure.
87 * @kobj: device's kobject.
89 * This is called once the reference count for the object
90 * reaches 0. We forward the call to the device's release
91 * method, which should handle actually freeing the structure.
93 static void device_release(struct kobject
* kobj
)
95 struct device
* dev
= to_dev(kobj
);
99 else if (dev
->type
&& dev
->type
->release
)
100 dev
->type
->release(dev
);
101 else if (dev
->class && dev
->class->dev_release
)
102 dev
->class->dev_release(dev
);
104 printk(KERN_ERR
"Device '%s' does not have a release() function, "
105 "it is broken and must be fixed.\n",
111 static struct kobj_type device_ktype
= {
112 .release
= device_release
,
113 .sysfs_ops
= &dev_sysfs_ops
,
117 static int dev_uevent_filter(struct kset
*kset
, struct kobject
*kobj
)
119 struct kobj_type
*ktype
= get_ktype(kobj
);
121 if (ktype
== &device_ktype
) {
122 struct device
*dev
= to_dev(kobj
);
123 if (dev
->uevent_suppress
)
133 static const char *dev_uevent_name(struct kset
*kset
, struct kobject
*kobj
)
135 struct device
*dev
= to_dev(kobj
);
138 return dev
->bus
->name
;
140 return dev
->class->name
;
144 static int dev_uevent(struct kset
*kset
, struct kobject
*kobj
,
145 struct kobj_uevent_env
*env
)
147 struct device
*dev
= to_dev(kobj
);
150 /* add the major/minor if present */
151 if (MAJOR(dev
->devt
)) {
152 add_uevent_var(env
, "MAJOR=%u", MAJOR(dev
->devt
));
153 add_uevent_var(env
, "MINOR=%u", MINOR(dev
->devt
));
156 if (dev
->type
&& dev
->type
->name
)
157 add_uevent_var(env
, "DEVTYPE=%s", dev
->type
->name
);
160 add_uevent_var(env
, "DRIVER=%s", dev
->driver
->name
);
162 #ifdef CONFIG_SYSFS_DEPRECATED
164 struct device
*parent
= dev
->parent
;
166 /* find first bus device in parent chain */
167 while (parent
&& !parent
->bus
)
168 parent
= parent
->parent
;
169 if (parent
&& parent
->bus
) {
172 path
= kobject_get_path(&parent
->kobj
, GFP_KERNEL
);
174 add_uevent_var(env
, "PHYSDEVPATH=%s", path
);
178 add_uevent_var(env
, "PHYSDEVBUS=%s", parent
->bus
->name
);
181 add_uevent_var(env
, "PHYSDEVDRIVER=%s",
182 parent
->driver
->name
);
184 } else if (dev
->bus
) {
185 add_uevent_var(env
, "PHYSDEVBUS=%s", dev
->bus
->name
);
188 add_uevent_var(env
, "PHYSDEVDRIVER=%s", dev
->driver
->name
);
192 /* have the bus specific function add its stuff */
193 if (dev
->bus
&& dev
->bus
->uevent
) {
194 retval
= dev
->bus
->uevent(dev
, env
);
196 pr_debug("device: '%s': %s: bus uevent() returned %d\n",
197 dev
->bus_id
, __FUNCTION__
, retval
);
200 /* have the class specific function add its stuff */
201 if (dev
->class && dev
->class->dev_uevent
) {
202 retval
= dev
->class->dev_uevent(dev
, env
);
204 pr_debug("device: '%s': %s: class uevent() "
205 "returned %d\n", dev
->bus_id
,
206 __FUNCTION__
, retval
);
209 /* have the device type specific fuction add its stuff */
210 if (dev
->type
&& dev
->type
->uevent
) {
211 retval
= dev
->type
->uevent(dev
, env
);
213 pr_debug("device: '%s': %s: dev_type uevent() "
214 "returned %d\n", dev
->bus_id
,
215 __FUNCTION__
, retval
);
221 static struct kset_uevent_ops device_uevent_ops
= {
222 .filter
= dev_uevent_filter
,
223 .name
= dev_uevent_name
,
224 .uevent
= dev_uevent
,
227 static ssize_t
show_uevent(struct device
*dev
, struct device_attribute
*attr
,
230 struct kobject
*top_kobj
;
232 struct kobj_uevent_env
*env
= NULL
;
237 /* search the kset, the device belongs to */
238 top_kobj
= &dev
->kobj
;
239 while (!top_kobj
->kset
&& top_kobj
->parent
)
240 top_kobj
= top_kobj
->parent
;
244 kset
= top_kobj
->kset
;
245 if (!kset
->uevent_ops
|| !kset
->uevent_ops
->uevent
)
249 if (kset
->uevent_ops
&& kset
->uevent_ops
->filter
)
250 if (!kset
->uevent_ops
->filter(kset
, &dev
->kobj
))
253 env
= kzalloc(sizeof(struct kobj_uevent_env
), GFP_KERNEL
);
257 /* let the kset specific function add its keys */
258 retval
= kset
->uevent_ops
->uevent(kset
, &dev
->kobj
, env
);
262 /* copy keys to file */
263 for (i
= 0; i
< env
->envp_idx
; i
++)
264 count
+= sprintf(&buf
[count
], "%s\n", env
->envp
[i
]);
270 static ssize_t
store_uevent(struct device
*dev
, struct device_attribute
*attr
,
271 const char *buf
, size_t count
)
273 enum kobject_action action
;
275 if (kobject_action_type(buf
, count
, &action
) == 0) {
276 kobject_uevent(&dev
->kobj
, action
);
280 dev_err(dev
, "uevent: unsupported action-string; this will "
281 "be ignored in a future kernel version\n");
282 kobject_uevent(&dev
->kobj
, KOBJ_ADD
);
287 static struct device_attribute uevent_attr
=
288 __ATTR(uevent
, S_IRUGO
| S_IWUSR
, show_uevent
, store_uevent
);
290 static int device_add_attributes(struct device
*dev
,
291 struct device_attribute
*attrs
)
297 for (i
= 0; attr_name(attrs
[i
]); i
++) {
298 error
= device_create_file(dev
, &attrs
[i
]);
304 device_remove_file(dev
, &attrs
[i
]);
309 static void device_remove_attributes(struct device
*dev
,
310 struct device_attribute
*attrs
)
315 for (i
= 0; attr_name(attrs
[i
]); i
++)
316 device_remove_file(dev
, &attrs
[i
]);
319 static int device_add_groups(struct device
*dev
,
320 struct attribute_group
**groups
)
326 for (i
= 0; groups
[i
]; i
++) {
327 error
= sysfs_create_group(&dev
->kobj
, groups
[i
]);
330 sysfs_remove_group(&dev
->kobj
, groups
[i
]);
338 static void device_remove_groups(struct device
*dev
,
339 struct attribute_group
**groups
)
344 for (i
= 0; groups
[i
]; i
++)
345 sysfs_remove_group(&dev
->kobj
, groups
[i
]);
348 static int device_add_attrs(struct device
*dev
)
350 struct class *class = dev
->class;
351 struct device_type
*type
= dev
->type
;
355 error
= device_add_attributes(dev
, class->dev_attrs
);
361 error
= device_add_groups(dev
, type
->groups
);
363 goto err_remove_class_attrs
;
366 error
= device_add_groups(dev
, dev
->groups
);
368 goto err_remove_type_groups
;
372 err_remove_type_groups
:
374 device_remove_groups(dev
, type
->groups
);
375 err_remove_class_attrs
:
377 device_remove_attributes(dev
, class->dev_attrs
);
382 static void device_remove_attrs(struct device
*dev
)
384 struct class *class = dev
->class;
385 struct device_type
*type
= dev
->type
;
387 device_remove_groups(dev
, dev
->groups
);
390 device_remove_groups(dev
, type
->groups
);
393 device_remove_attributes(dev
, class->dev_attrs
);
397 static ssize_t
show_dev(struct device
*dev
, struct device_attribute
*attr
,
400 return print_dev_t(buf
, dev
->devt
);
403 static struct device_attribute devt_attr
=
404 __ATTR(dev
, S_IRUGO
, show_dev
, NULL
);
406 /* kset to create /sys/devices/ */
407 struct kset
*devices_kset
;
411 * device_create_file - create sysfs attribute file for device.
413 * @attr: device attribute descriptor.
416 int device_create_file(struct device
* dev
, struct device_attribute
* attr
)
419 if (get_device(dev
)) {
420 error
= sysfs_create_file(&dev
->kobj
, &attr
->attr
);
427 * device_remove_file - remove sysfs attribute file.
429 * @attr: device attribute descriptor.
432 void device_remove_file(struct device
* dev
, struct device_attribute
* attr
)
434 if (get_device(dev
)) {
435 sysfs_remove_file(&dev
->kobj
, &attr
->attr
);
441 * device_create_bin_file - create sysfs binary attribute file for device.
443 * @attr: device binary attribute descriptor.
445 int device_create_bin_file(struct device
*dev
, struct bin_attribute
*attr
)
449 error
= sysfs_create_bin_file(&dev
->kobj
, attr
);
452 EXPORT_SYMBOL_GPL(device_create_bin_file
);
455 * device_remove_bin_file - remove sysfs binary attribute file
457 * @attr: device binary attribute descriptor.
459 void device_remove_bin_file(struct device
*dev
, struct bin_attribute
*attr
)
462 sysfs_remove_bin_file(&dev
->kobj
, attr
);
464 EXPORT_SYMBOL_GPL(device_remove_bin_file
);
467 * device_schedule_callback_owner - helper to schedule a callback for a device
469 * @func: callback function to invoke later.
470 * @owner: module owning the callback routine
472 * Attribute methods must not unregister themselves or their parent device
473 * (which would amount to the same thing). Attempts to do so will deadlock,
474 * since unregistration is mutually exclusive with driver callbacks.
476 * Instead methods can call this routine, which will attempt to allocate
477 * and schedule a workqueue request to call back @func with @dev as its
478 * argument in the workqueue's process context. @dev will be pinned until
481 * This routine is usually called via the inline device_schedule_callback(),
482 * which automatically sets @owner to THIS_MODULE.
484 * Returns 0 if the request was submitted, -ENOMEM if storage could not
485 * be allocated, -ENODEV if a reference to @owner isn't available.
487 * NOTE: This routine won't work if CONFIG_SYSFS isn't set! It uses an
488 * underlying sysfs routine (since it is intended for use by attribute
489 * methods), and if sysfs isn't available you'll get nothing but -ENOSYS.
491 int device_schedule_callback_owner(struct device
*dev
,
492 void (*func
)(struct device
*), struct module
*owner
)
494 return sysfs_schedule_callback(&dev
->kobj
,
495 (void (*)(void *)) func
, dev
, owner
);
497 EXPORT_SYMBOL_GPL(device_schedule_callback_owner
);
499 static void klist_children_get(struct klist_node
*n
)
501 struct device
*dev
= container_of(n
, struct device
, knode_parent
);
506 static void klist_children_put(struct klist_node
*n
)
508 struct device
*dev
= container_of(n
, struct device
, knode_parent
);
515 * device_initialize - init device structure.
518 * This prepares the device for use by other layers,
519 * including adding it to the device hierarchy.
520 * It is the first half of device_register(), if called by
521 * that, though it can also be called separately, so one
522 * 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_ng(&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
) {}
556 static struct kobject
*virtual_device_parent(struct device
*dev
)
558 static struct kobject
*virtual_dir
= NULL
;
561 virtual_dir
= kobject_create_and_add("virtual",
562 &devices_kset
->kobj
);
567 static struct kobject
*get_device_parent(struct device
*dev
,
568 struct device
*parent
)
573 struct kobject
*kobj
= NULL
;
574 struct kobject
*parent_kobj
;
578 * If we have no parent, we live in "virtual".
579 * Class-devices with a bus-device as parent, live
580 * in a class-directory to prevent namespace collisions.
583 parent_kobj
= virtual_device_parent(dev
);
584 else if (parent
->class)
585 return &parent
->kobj
;
587 parent_kobj
= &parent
->kobj
;
589 /* find our class-directory at the parent and reference it */
590 spin_lock(&dev
->class->class_dirs
.list_lock
);
591 list_for_each_entry(k
, &dev
->class->class_dirs
.list
, entry
)
592 if (k
->parent
== parent_kobj
) {
593 kobj
= kobject_get(k
);
596 spin_unlock(&dev
->class->class_dirs
.list_lock
);
600 /* or create a new class-directory at the parent device */
601 k
= kobject_create();
604 k
->kset
= &dev
->class->class_dirs
;
605 retval
= kobject_add(k
, parent_kobj
, "%s", dev
->class->name
);
610 /* Do not emit a uevent, as it's not needed for this
611 * "class glue" directory. */
616 return &parent
->kobj
;
620 static void cleanup_device_parent(struct device
*dev
)
628 /* see if we live in a parent class directory */
629 if (dev
->kobj
.parent
->kset
!= &dev
->class->class_dirs
)
632 /* if we are the last child of our class, delete the directory */
633 down(&dev
->class->sem
);
634 list_for_each_entry(d
, &dev
->class->devices
, node
) {
637 if (d
->kobj
.parent
== dev
->kobj
.parent
) {
643 kobject_del(dev
->kobj
.parent
);
644 kobject_put(dev
->kobj
.parent
);
645 up(&dev
->class->sem
);
649 static int setup_parent(struct device
*dev
, struct device
*parent
)
651 struct kobject
*kobj
;
652 kobj
= get_device_parent(dev
, parent
);
654 return PTR_ERR(kobj
);
656 dev
->kobj
.parent
= kobj
;
660 static int device_add_class_symlinks(struct device
*dev
)
667 error
= sysfs_create_link(&dev
->kobj
, &dev
->class->subsys
.kobj
,
672 #ifdef CONFIG_SYSFS_DEPRECATED
673 /* stacked class devices need a symlink in the class directory */
674 if (dev
->kobj
.parent
!= &dev
->class->subsys
.kobj
&&
675 dev
->type
!= &part_type
) {
676 error
= sysfs_create_link(&dev
->class->subsys
.kobj
, &dev
->kobj
,
682 if (dev
->parent
&& dev
->type
!= &part_type
) {
683 struct device
*parent
= dev
->parent
;
687 * stacked class devices have the 'device' link
688 * pointing to the bus device instead of the parent
690 while (parent
->class && !parent
->bus
&& parent
->parent
)
691 parent
= parent
->parent
;
693 error
= sysfs_create_link(&dev
->kobj
,
699 class_name
= make_class_name(dev
->class->name
,
702 error
= sysfs_create_link(&dev
->parent
->kobj
,
703 &dev
->kobj
, class_name
);
711 if (dev
->parent
&& dev
->type
!= &part_type
)
712 sysfs_remove_link(&dev
->kobj
, "device");
714 if (dev
->kobj
.parent
!= &dev
->class->subsys
.kobj
&&
715 dev
->type
!= &part_type
)
716 sysfs_remove_link(&dev
->class->subsys
.kobj
, dev
->bus_id
);
718 /* link in the class directory pointing to the device */
719 error
= sysfs_create_link(&dev
->class->subsys
.kobj
, &dev
->kobj
,
724 if (dev
->parent
&& dev
->type
!= &part_type
) {
725 error
= sysfs_create_link(&dev
->kobj
, &dev
->parent
->kobj
,
733 sysfs_remove_link(&dev
->class->subsys
.kobj
, dev
->bus_id
);
737 sysfs_remove_link(&dev
->kobj
, "subsystem");
742 static void device_remove_class_symlinks(struct device
*dev
)
747 #ifdef CONFIG_SYSFS_DEPRECATED
748 if (dev
->parent
&& dev
->type
!= &part_type
) {
751 class_name
= make_class_name(dev
->class->name
, &dev
->kobj
);
753 sysfs_remove_link(&dev
->parent
->kobj
, class_name
);
756 sysfs_remove_link(&dev
->kobj
, "device");
759 if (dev
->kobj
.parent
!= &dev
->class->subsys
.kobj
&&
760 dev
->type
!= &part_type
)
761 sysfs_remove_link(&dev
->class->subsys
.kobj
, dev
->bus_id
);
763 if (dev
->parent
&& dev
->type
!= &part_type
)
764 sysfs_remove_link(&dev
->kobj
, "device");
766 sysfs_remove_link(&dev
->class->subsys
.kobj
, dev
->bus_id
);
769 sysfs_remove_link(&dev
->kobj
, "subsystem");
773 * device_add - add device to device hierarchy.
776 * This is part 2 of device_register(), though may be called
777 * separately _iff_ device_initialize() has been called separately.
779 * This adds it to the kobject hierarchy via kobject_add(), adds it
780 * to the global and sibling lists for the device, then
781 * adds it to the other relevant subsystems of the driver model.
783 int device_add(struct device
*dev
)
785 struct device
*parent
= NULL
;
786 struct class_interface
*class_intf
;
789 error
= pm_sleep_lock();
791 dev_warn(dev
, "Suspicious %s during suspend\n", __FUNCTION__
);
796 dev
= get_device(dev
);
797 if (!dev
|| !strlen(dev
->bus_id
)) {
802 pr_debug("device: '%s': %s\n", dev
->bus_id
, __FUNCTION__
);
804 parent
= get_device(dev
->parent
);
805 error
= setup_parent(dev
, parent
);
809 /* first, register with generic layer. */
810 error
= kobject_add(&dev
->kobj
, dev
->kobj
.parent
, "%s", dev
->bus_id
);
814 /* notify platform of device entry */
816 platform_notify(dev
);
818 /* notify clients of device entry (new way) */
820 blocking_notifier_call_chain(&dev
->bus
->p
->bus_notifier
,
821 BUS_NOTIFY_ADD_DEVICE
, dev
);
823 error
= device_create_file(dev
, &uevent_attr
);
827 if (MAJOR(dev
->devt
)) {
828 error
= device_create_file(dev
, &devt_attr
);
830 goto ueventattrError
;
833 error
= device_add_class_symlinks(dev
);
836 error
= device_add_attrs(dev
);
839 error
= dpm_sysfs_add(dev
);
843 error
= bus_add_device(dev
);
846 kobject_uevent(&dev
->kobj
, KOBJ_ADD
);
847 bus_attach_device(dev
);
849 klist_add_tail(&dev
->knode_parent
, &parent
->klist_children
);
852 down(&dev
->class->sem
);
853 /* tie the class to the device */
854 list_add_tail(&dev
->node
, &dev
->class->devices
);
856 /* notify any interfaces that the device is here */
857 list_for_each_entry(class_intf
, &dev
->class->interfaces
, node
)
858 if (class_intf
->add_dev
)
859 class_intf
->add_dev(dev
, class_intf
);
860 up(&dev
->class->sem
);
867 device_pm_remove(dev
);
868 dpm_sysfs_remove(dev
);
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
);
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.
903 int device_register(struct device
*dev
)
905 device_initialize(dev
);
906 return device_add(dev
);
911 * get_device - increment reference count for device.
914 * This simply forwards the call to kobject_get(), though
915 * we do take care to provide for the case that we get a NULL
919 struct device
* get_device(struct device
* dev
)
921 return dev
? to_dev(kobject_get(&dev
->kobj
)) : NULL
;
926 * put_device - decrement reference count.
927 * @dev: device in question.
929 void put_device(struct device
* dev
)
933 kobject_put(&dev
->kobj
);
938 * device_del - delete device from system.
941 * This is the first part of the device unregistration
942 * sequence. This removes the device from the lists we control
943 * from here, has it removed from the other driver model
944 * subsystems it was added to in device_add(), and removes it
945 * from the kobject hierarchy.
947 * NOTE: this should be called manually _iff_ device_add() was
948 * also called manually.
951 void device_del(struct device
* dev
)
953 struct device
* parent
= dev
->parent
;
954 struct class_interface
*class_intf
;
956 device_pm_remove(dev
);
958 klist_del(&dev
->knode_parent
);
959 if (MAJOR(dev
->devt
))
960 device_remove_file(dev
, &devt_attr
);
962 device_remove_class_symlinks(dev
);
964 down(&dev
->class->sem
);
965 /* notify any interfaces that the device is now gone */
966 list_for_each_entry(class_intf
, &dev
->class->interfaces
, node
)
967 if (class_intf
->remove_dev
)
968 class_intf
->remove_dev(dev
, class_intf
);
969 /* remove the device from the class list */
970 list_del_init(&dev
->node
);
971 up(&dev
->class->sem
);
973 device_remove_file(dev
, &uevent_attr
);
974 device_remove_attrs(dev
);
975 bus_remove_device(dev
);
978 * Some platform devices are driven without driver attached
979 * and managed resources may have been acquired. Make sure
980 * all resources are released.
982 devres_release_all(dev
);
984 /* Notify the platform of the removal, in case they
985 * need to do anything...
987 if (platform_notify_remove
)
988 platform_notify_remove(dev
);
990 blocking_notifier_call_chain(&dev
->bus
->p
->bus_notifier
,
991 BUS_NOTIFY_DEL_DEVICE
, dev
);
992 kobject_uevent(&dev
->kobj
, KOBJ_REMOVE
);
993 cleanup_device_parent(dev
);
994 kobject_del(&dev
->kobj
);
999 * device_unregister - unregister device from system.
1000 * @dev: device going away.
1002 * We do this in two parts, like we do device_register(). First,
1003 * we remove it from all the subsystems with device_del(), then
1004 * we decrement the reference count via put_device(). If that
1005 * is the final reference count, the device will be cleaned up
1006 * via device_release() above. Otherwise, the structure will
1007 * stick around until the final reference to the device is dropped.
1009 void device_unregister(struct device
* dev
)
1011 pr_debug("device: '%s': %s\n", dev
->bus_id
, __FUNCTION__
);
1017 static struct device
* next_device(struct klist_iter
* i
)
1019 struct klist_node
* n
= klist_next(i
);
1020 return n
? container_of(n
, struct device
, knode_parent
) : NULL
;
1024 * device_for_each_child - device child iterator.
1025 * @parent: parent struct device.
1026 * @data: data for the callback.
1027 * @fn: function to be called for each device.
1029 * Iterate over @parent's child devices, and call @fn for each,
1032 * We check the return of @fn each time. If it returns anything
1033 * other than 0, we break out and return that value.
1035 int device_for_each_child(struct device
* parent
, void * data
,
1036 int (*fn
)(struct device
*, void *))
1038 struct klist_iter i
;
1039 struct device
* child
;
1042 klist_iter_init(&parent
->klist_children
, &i
);
1043 while ((child
= next_device(&i
)) && !error
)
1044 error
= fn(child
, data
);
1045 klist_iter_exit(&i
);
1050 * device_find_child - device iterator for locating a particular device.
1051 * @parent: parent struct device
1052 * @data: Data to pass to match function
1053 * @match: Callback function to check device
1055 * This is similar to the device_for_each_child() function above, but it
1056 * returns a reference to a device that is 'found' for later use, as
1057 * determined by the @match callback.
1059 * The callback should return 0 if the device doesn't match and non-zero
1060 * if it does. If the callback returns non-zero and a reference to the
1061 * current device can be obtained, this function will return to the caller
1062 * and not iterate over any more devices.
1064 struct device
* device_find_child(struct device
*parent
, void *data
,
1065 int (*match
)(struct device
*, void *))
1067 struct klist_iter i
;
1068 struct device
*child
;
1073 klist_iter_init(&parent
->klist_children
, &i
);
1074 while ((child
= next_device(&i
)))
1075 if (match(child
, data
) && get_device(child
))
1077 klist_iter_exit(&i
);
1081 int __init
devices_init(void)
1083 devices_kset
= kset_create_and_add("devices", &device_uevent_ops
, NULL
);
1089 EXPORT_SYMBOL_GPL(device_for_each_child
);
1090 EXPORT_SYMBOL_GPL(device_find_child
);
1092 EXPORT_SYMBOL_GPL(device_initialize
);
1093 EXPORT_SYMBOL_GPL(device_add
);
1094 EXPORT_SYMBOL_GPL(device_register
);
1096 EXPORT_SYMBOL_GPL(device_del
);
1097 EXPORT_SYMBOL_GPL(device_unregister
);
1098 EXPORT_SYMBOL_GPL(get_device
);
1099 EXPORT_SYMBOL_GPL(put_device
);
1101 EXPORT_SYMBOL_GPL(device_create_file
);
1102 EXPORT_SYMBOL_GPL(device_remove_file
);
1105 static void device_create_release(struct device
*dev
)
1107 pr_debug("device: '%s': %s\n", dev
->bus_id
, __FUNCTION__
);
1112 * device_create - creates a device and registers it with sysfs
1113 * @class: pointer to the struct class that this device should be registered to
1114 * @parent: pointer to the parent struct device of this new device, if any
1115 * @devt: the dev_t for the char device to be added
1116 * @fmt: string for the device's name
1118 * This function can be used by char device classes. A struct device
1119 * will be created in sysfs, registered to the specified class.
1121 * A "dev" file will be created, showing the dev_t for the device, if
1122 * the dev_t is not 0,0.
1123 * If a pointer to a parent struct device is passed in, the newly created
1124 * struct device will be a child of that device in sysfs.
1125 * The pointer to the struct device will be returned from the call.
1126 * Any further sysfs files that might be required can be created using this
1129 * Note: the struct class passed to this function must have previously
1130 * been created with a call to class_create().
1132 struct device
*device_create(struct class *class, struct device
*parent
,
1133 dev_t devt
, const char *fmt
, ...)
1136 struct device
*dev
= NULL
;
1137 int retval
= -ENODEV
;
1139 if (class == NULL
|| IS_ERR(class))
1142 dev
= kzalloc(sizeof(*dev
), GFP_KERNEL
);
1150 dev
->parent
= parent
;
1151 dev
->release
= device_create_release
;
1153 va_start(args
, fmt
);
1154 vsnprintf(dev
->bus_id
, BUS_ID_SIZE
, fmt
, args
);
1156 retval
= device_register(dev
);
1164 return ERR_PTR(retval
);
1166 EXPORT_SYMBOL_GPL(device_create
);
1169 * find_device - finds 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 static struct device
*find_device(struct class *class, dev_t devt
)
1175 struct device
*dev
= NULL
;
1176 struct device
*dev_tmp
;
1179 list_for_each_entry(dev_tmp
, &class->devices
, node
) {
1180 if (dev_tmp
->devt
== devt
) {
1190 * device_destroy - removes a device that was created with device_create()
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 unregisters and cleans up a device that was created with a
1195 * call to device_create().
1197 void device_destroy(struct class *class, dev_t devt
)
1201 dev
= find_device(class, devt
);
1203 device_unregister(dev
);
1205 EXPORT_SYMBOL_GPL(device_destroy
);
1207 #ifdef CONFIG_PM_SLEEP
1209 * destroy_suspended_device - asks the PM core to remove a suspended device
1210 * @class: pointer to the struct class that this device was registered with
1211 * @devt: the dev_t of the device that was previously registered
1213 * This call notifies the PM core of the necessity to unregister a suspended
1214 * device created with a call to device_create() (devices cannot be
1215 * unregistered directly while suspended, since the PM core holds their
1216 * semaphores at that time).
1218 * It can only be called within the scope of a system sleep transition. In
1219 * practice this means it has to be directly or indirectly invoked either by
1220 * a suspend or resume method, or by the PM core (e.g. via
1221 * disable_nonboot_cpus() or enable_nonboot_cpus()).
1223 void destroy_suspended_device(struct class *class, dev_t devt
)
1227 dev
= find_device(class, devt
);
1229 device_pm_schedule_removal(dev
);
1231 EXPORT_SYMBOL_GPL(destroy_suspended_device
);
1232 #endif /* CONFIG_PM_SLEEP */
1235 * device_rename - renames a device
1236 * @dev: the pointer to the struct device to be renamed
1237 * @new_name: the new name of the device
1239 int device_rename(struct device
*dev
, char *new_name
)
1241 char *old_class_name
= NULL
;
1242 char *new_class_name
= NULL
;
1243 char *old_device_name
= NULL
;
1246 dev
= get_device(dev
);
1250 pr_debug("device: '%s': %s: renaming to '%s'\n", dev
->bus_id
,
1251 __FUNCTION__
, new_name
);
1253 #ifdef CONFIG_SYSFS_DEPRECATED
1254 if ((dev
->class) && (dev
->parent
))
1255 old_class_name
= make_class_name(dev
->class->name
, &dev
->kobj
);
1258 old_device_name
= kmalloc(BUS_ID_SIZE
, GFP_KERNEL
);
1259 if (!old_device_name
) {
1263 strlcpy(old_device_name
, dev
->bus_id
, BUS_ID_SIZE
);
1264 strlcpy(dev
->bus_id
, new_name
, BUS_ID_SIZE
);
1266 error
= kobject_rename(&dev
->kobj
, new_name
);
1268 strlcpy(dev
->bus_id
, old_device_name
, BUS_ID_SIZE
);
1272 #ifdef CONFIG_SYSFS_DEPRECATED
1273 if (old_class_name
) {
1274 new_class_name
= make_class_name(dev
->class->name
, &dev
->kobj
);
1275 if (new_class_name
) {
1276 error
= sysfs_create_link(&dev
->parent
->kobj
,
1277 &dev
->kobj
, new_class_name
);
1280 sysfs_remove_link(&dev
->parent
->kobj
, old_class_name
);
1285 sysfs_remove_link(&dev
->class->subsys
.kobj
, old_device_name
);
1286 error
= sysfs_create_link(&dev
->class->subsys
.kobj
, &dev
->kobj
,
1289 dev_err(dev
, "%s: sysfs_create_symlink failed (%d)\n",
1290 __FUNCTION__
, error
);
1298 kfree(new_class_name
);
1299 kfree(old_class_name
);
1300 kfree(old_device_name
);
1304 EXPORT_SYMBOL_GPL(device_rename
);
1306 static int device_move_class_links(struct device
*dev
,
1307 struct device
*old_parent
,
1308 struct device
*new_parent
)
1311 #ifdef CONFIG_SYSFS_DEPRECATED
1314 class_name
= make_class_name(dev
->class->name
, &dev
->kobj
);
1320 sysfs_remove_link(&dev
->kobj
, "device");
1321 sysfs_remove_link(&old_parent
->kobj
, class_name
);
1324 error
= sysfs_create_link(&dev
->kobj
, &new_parent
->kobj
,
1328 error
= sysfs_create_link(&new_parent
->kobj
, &dev
->kobj
,
1331 sysfs_remove_link(&dev
->kobj
, "device");
1340 sysfs_remove_link(&dev
->kobj
, "device");
1342 error
= sysfs_create_link(&dev
->kobj
, &new_parent
->kobj
,
1349 * device_move - moves a device to a new parent
1350 * @dev: the pointer to the struct device to be moved
1351 * @new_parent: the new parent of the device (can by NULL)
1353 int device_move(struct device
*dev
, struct device
*new_parent
)
1356 struct device
*old_parent
;
1357 struct kobject
*new_parent_kobj
;
1359 dev
= get_device(dev
);
1363 new_parent
= get_device(new_parent
);
1364 new_parent_kobj
= get_device_parent (dev
, new_parent
);
1365 if (IS_ERR(new_parent_kobj
)) {
1366 error
= PTR_ERR(new_parent_kobj
);
1367 put_device(new_parent
);
1370 pr_debug("device: '%s': %s: moving to '%s'\n", dev
->bus_id
,
1371 __FUNCTION__
, new_parent
? new_parent
->bus_id
: "<NULL>");
1372 error
= kobject_move(&dev
->kobj
, new_parent_kobj
);
1374 put_device(new_parent
);
1377 old_parent
= dev
->parent
;
1378 dev
->parent
= new_parent
;
1380 klist_remove(&dev
->knode_parent
);
1382 klist_add_tail(&dev
->knode_parent
, &new_parent
->klist_children
);
1385 error
= device_move_class_links(dev
, old_parent
, new_parent
);
1387 /* We ignore errors on cleanup since we're hosed anyway... */
1388 device_move_class_links(dev
, new_parent
, old_parent
);
1389 if (!kobject_move(&dev
->kobj
, &old_parent
->kobj
)) {
1391 klist_remove(&dev
->knode_parent
);
1393 klist_add_tail(&dev
->knode_parent
,
1394 &old_parent
->klist_children
);
1396 put_device(new_parent
);
1400 put_device(old_parent
);
1405 EXPORT_SYMBOL_GPL(device_move
);
1408 * device_shutdown - call ->shutdown() on each device to shutdown.
1410 void device_shutdown(void)
1412 struct device
* dev
, *devn
;
1414 list_for_each_entry_safe_reverse(dev
, devn
, &devices_kset
->list
,
1416 if (dev
->bus
&& dev
->bus
->shutdown
) {
1417 dev_dbg(dev
, "shutdown\n");
1418 dev
->bus
->shutdown(dev
);
1419 } else if (dev
->driver
&& dev
->driver
->shutdown
) {
1420 dev_dbg(dev
, "shutdown\n");
1421 dev
->driver
->shutdown(dev
);