2 * device.h - generic, centralized driver model
4 * Copyright (c) 2001-2003 Patrick Mochel <mochel@osdl.org>
5 * Copyright (c) 2004-2009 Greg Kroah-Hartman <gregkh@suse.de>
6 * Copyright (c) 2008-2009 Novell Inc.
8 * This file is released under the GPLv2
10 * See Documentation/driver-model/ for more information.
16 #include <linux/ioport.h>
17 #include <linux/kobject.h>
18 #include <linux/klist.h>
19 #include <linux/list.h>
20 #include <linux/lockdep.h>
21 #include <linux/compiler.h>
22 #include <linux/types.h>
23 #include <linux/mutex.h>
24 #include <linux/pinctrl/devinfo.h>
26 #include <linux/atomic.h>
27 #include <linux/ratelimit.h>
28 #include <linux/uidgid.h>
29 #include <linux/gfp.h>
30 #include <asm/device.h>
33 struct device_private;
35 struct driver_private;
38 struct subsys_private;
44 struct bus_attribute {
45 struct attribute attr;
46 ssize_t (*show)(struct bus_type *bus, char *buf);
47 ssize_t (*store)(struct bus_type *bus, const char *buf, size_t count);
50 #define BUS_ATTR(_name, _mode, _show, _store) \
51 struct bus_attribute bus_attr_##_name = __ATTR(_name, _mode, _show, _store)
52 #define BUS_ATTR_RW(_name) \
53 struct bus_attribute bus_attr_##_name = __ATTR_RW(_name)
54 #define BUS_ATTR_RO(_name) \
55 struct bus_attribute bus_attr_##_name = __ATTR_RO(_name)
57 extern int __must_check bus_create_file(struct bus_type *,
58 struct bus_attribute *);
59 extern void bus_remove_file(struct bus_type *, struct bus_attribute *);
62 * struct bus_type - The bus type of the device
64 * @name: The name of the bus.
65 * @dev_name: Used for subsystems to enumerate devices like ("foo%u", dev->id).
66 * @dev_root: Default device to use as the parent.
67 * @dev_attrs: Default attributes of the devices on the bus.
68 * @bus_groups: Default attributes of the bus.
69 * @dev_groups: Default attributes of the devices on the bus.
70 * @drv_groups: Default attributes of the device drivers on the bus.
71 * @match: Called, perhaps multiple times, whenever a new device or driver
72 * is added for this bus. It should return a nonzero value if the
73 * given device can be handled by the given driver.
74 * @uevent: Called when a device is added, removed, or a few other things
75 * that generate uevents to add the environment variables.
76 * @probe: Called when a new device or driver add to this bus, and callback
77 * the specific driver's probe to initial the matched device.
78 * @remove: Called when a device removed from this bus.
79 * @shutdown: Called at shut-down time to quiesce the device.
81 * @online: Called to put the device back online (after offlining it).
82 * @offline: Called to put the device offline for hot-removal. May fail.
84 * @suspend: Called when a device on this bus wants to go to sleep mode.
85 * @resume: Called to bring a device on this bus out of sleep mode.
86 * @pm: Power management operations of this bus, callback the specific
87 * device driver's pm-ops.
88 * @iommu_ops: IOMMU specific operations for this bus, used to attach IOMMU
89 * driver implementations to a bus and allow the driver to do
91 * @p: The private data of the driver core, only the driver core can
93 * @lock_key: Lock class key for use by the lock validator
95 * A bus is a channel between the processor and one or more devices. For the
96 * purposes of the device model, all devices are connected via a bus, even if
97 * it is an internal, virtual, "platform" bus. Buses can plug into each other.
98 * A USB controller is usually a PCI device, for example. The device model
99 * represents the actual connections between buses and the devices they control.
100 * A bus is represented by the bus_type structure. It contains the name, the
101 * default attributes, the bus' methods, PM operations, and the driver core's
106 const char *dev_name;
107 struct device *dev_root;
108 struct device_attribute *dev_attrs; /* use dev_groups instead */
109 const struct attribute_group **bus_groups;
110 const struct attribute_group **dev_groups;
111 const struct attribute_group **drv_groups;
113 int (*match)(struct device *dev, struct device_driver *drv);
114 int (*uevent)(struct device *dev, struct kobj_uevent_env *env);
115 int (*probe)(struct device *dev);
116 int (*remove)(struct device *dev);
117 void (*shutdown)(struct device *dev);
119 int (*online)(struct device *dev);
120 int (*offline)(struct device *dev);
122 int (*suspend)(struct device *dev, pm_message_t state);
123 int (*resume)(struct device *dev);
125 const struct dev_pm_ops *pm;
127 const struct iommu_ops *iommu_ops;
129 struct subsys_private *p;
130 struct lock_class_key lock_key;
133 extern int __must_check bus_register(struct bus_type *bus);
135 extern void bus_unregister(struct bus_type *bus);
137 extern int __must_check bus_rescan_devices(struct bus_type *bus);
139 /* iterator helpers for buses */
140 struct subsys_dev_iter {
141 struct klist_iter ki;
142 const struct device_type *type;
144 void subsys_dev_iter_init(struct subsys_dev_iter *iter,
145 struct bus_type *subsys,
146 struct device *start,
147 const struct device_type *type);
148 struct device *subsys_dev_iter_next(struct subsys_dev_iter *iter);
149 void subsys_dev_iter_exit(struct subsys_dev_iter *iter);
151 int bus_for_each_dev(struct bus_type *bus, struct device *start, void *data,
152 int (*fn)(struct device *dev, void *data));
153 struct device *bus_find_device(struct bus_type *bus, struct device *start,
155 int (*match)(struct device *dev, void *data));
156 struct device *bus_find_device_by_name(struct bus_type *bus,
157 struct device *start,
159 struct device *subsys_find_device_by_id(struct bus_type *bus, unsigned int id,
160 struct device *hint);
161 int bus_for_each_drv(struct bus_type *bus, struct device_driver *start,
162 void *data, int (*fn)(struct device_driver *, void *));
163 void bus_sort_breadthfirst(struct bus_type *bus,
164 int (*compare)(const struct device *a,
165 const struct device *b));
167 * Bus notifiers: Get notified of addition/removal of devices
168 * and binding/unbinding of drivers to devices.
169 * In the long run, it should be a replacement for the platform
172 struct notifier_block;
174 extern int bus_register_notifier(struct bus_type *bus,
175 struct notifier_block *nb);
176 extern int bus_unregister_notifier(struct bus_type *bus,
177 struct notifier_block *nb);
179 /* All 4 notifers below get called with the target struct device *
180 * as an argument. Note that those functions are likely to be called
181 * with the device lock held in the core, so be careful.
183 #define BUS_NOTIFY_ADD_DEVICE 0x00000001 /* device added */
184 #define BUS_NOTIFY_DEL_DEVICE 0x00000002 /* device to be removed */
185 #define BUS_NOTIFY_REMOVED_DEVICE 0x00000003 /* device removed */
186 #define BUS_NOTIFY_BIND_DRIVER 0x00000004 /* driver about to be
188 #define BUS_NOTIFY_BOUND_DRIVER 0x00000005 /* driver bound to device */
189 #define BUS_NOTIFY_UNBIND_DRIVER 0x00000006 /* driver about to be
191 #define BUS_NOTIFY_UNBOUND_DRIVER 0x00000007 /* driver is unbound
194 extern struct kset *bus_get_kset(struct bus_type *bus);
195 extern struct klist *bus_get_device_klist(struct bus_type *bus);
198 * struct device_driver - The basic device driver structure
199 * @name: Name of the device driver.
200 * @bus: The bus which the device of this driver belongs to.
201 * @owner: The module owner.
202 * @mod_name: Used for built-in modules.
203 * @suppress_bind_attrs: Disables bind/unbind via sysfs.
204 * @of_match_table: The open firmware table.
205 * @acpi_match_table: The ACPI match table.
206 * @probe: Called to query the existence of a specific device,
207 * whether this driver can work with it, and bind the driver
208 * to a specific device.
209 * @remove: Called when the device is removed from the system to
210 * unbind a device from this driver.
211 * @shutdown: Called at shut-down time to quiesce the device.
212 * @suspend: Called to put the device to sleep mode. Usually to a
214 * @resume: Called to bring a device from sleep mode.
215 * @groups: Default attributes that get created by the driver core
217 * @pm: Power management operations of the device which matched
219 * @p: Driver core's private data, no one other than the driver
220 * core can touch this.
222 * The device driver-model tracks all of the drivers known to the system.
223 * The main reason for this tracking is to enable the driver core to match
224 * up drivers with new devices. Once drivers are known objects within the
225 * system, however, a number of other things become possible. Device drivers
226 * can export information and configuration variables that are independent
227 * of any specific device.
229 struct device_driver {
231 struct bus_type *bus;
233 struct module *owner;
234 const char *mod_name; /* used for built-in modules */
236 bool suppress_bind_attrs; /* disables bind/unbind via sysfs */
238 const struct of_device_id *of_match_table;
239 const struct acpi_device_id *acpi_match_table;
241 int (*probe) (struct device *dev);
242 int (*remove) (struct device *dev);
243 void (*shutdown) (struct device *dev);
244 int (*suspend) (struct device *dev, pm_message_t state);
245 int (*resume) (struct device *dev);
246 const struct attribute_group **groups;
248 const struct dev_pm_ops *pm;
250 struct driver_private *p;
254 extern int __must_check driver_register(struct device_driver *drv);
255 extern void driver_unregister(struct device_driver *drv);
257 extern struct device_driver *driver_find(const char *name,
258 struct bus_type *bus);
259 extern int driver_probe_done(void);
260 extern void wait_for_device_probe(void);
263 /* sysfs interface for exporting driver attributes */
265 struct driver_attribute {
266 struct attribute attr;
267 ssize_t (*show)(struct device_driver *driver, char *buf);
268 ssize_t (*store)(struct device_driver *driver, const char *buf,
272 #define DRIVER_ATTR(_name, _mode, _show, _store) \
273 struct driver_attribute driver_attr_##_name = __ATTR(_name, _mode, _show, _store)
274 #define DRIVER_ATTR_RW(_name) \
275 struct driver_attribute driver_attr_##_name = __ATTR_RW(_name)
276 #define DRIVER_ATTR_RO(_name) \
277 struct driver_attribute driver_attr_##_name = __ATTR_RO(_name)
278 #define DRIVER_ATTR_WO(_name) \
279 struct driver_attribute driver_attr_##_name = __ATTR_WO(_name)
281 extern int __must_check driver_create_file(struct device_driver *driver,
282 const struct driver_attribute *attr);
283 extern void driver_remove_file(struct device_driver *driver,
284 const struct driver_attribute *attr);
286 extern int __must_check driver_for_each_device(struct device_driver *drv,
287 struct device *start,
289 int (*fn)(struct device *dev,
291 struct device *driver_find_device(struct device_driver *drv,
292 struct device *start, void *data,
293 int (*match)(struct device *dev, void *data));
296 * struct subsys_interface - interfaces to device functions
297 * @name: name of the device function
298 * @subsys: subsytem of the devices to attach to
299 * @node: the list of functions registered at the subsystem
300 * @add_dev: device hookup to device function handler
301 * @remove_dev: device hookup to device function handler
303 * Simple interfaces attached to a subsystem. Multiple interfaces can
304 * attach to a subsystem and its devices. Unlike drivers, they do not
305 * exclusively claim or control devices. Interfaces usually represent
306 * a specific functionality of a subsystem/class of devices.
308 struct subsys_interface {
310 struct bus_type *subsys;
311 struct list_head node;
312 int (*add_dev)(struct device *dev, struct subsys_interface *sif);
313 int (*remove_dev)(struct device *dev, struct subsys_interface *sif);
316 int subsys_interface_register(struct subsys_interface *sif);
317 void subsys_interface_unregister(struct subsys_interface *sif);
319 int subsys_system_register(struct bus_type *subsys,
320 const struct attribute_group **groups);
321 int subsys_virtual_register(struct bus_type *subsys,
322 const struct attribute_group **groups);
325 * struct class - device classes
326 * @name: Name of the class.
327 * @owner: The module owner.
328 * @class_attrs: Default attributes of this class.
329 * @dev_groups: Default attributes of the devices that belong to the class.
330 * @dev_kobj: The kobject that represents this class and links it into the hierarchy.
331 * @dev_uevent: Called when a device is added, removed from this class, or a
332 * few other things that generate uevents to add the environment
334 * @devnode: Callback to provide the devtmpfs.
335 * @class_release: Called to release this class.
336 * @dev_release: Called to release the device.
337 * @suspend: Used to put the device to sleep mode, usually to a low power
339 * @resume: Used to bring the device from the sleep mode.
340 * @ns_type: Callbacks so sysfs can detemine namespaces.
341 * @namespace: Namespace of the device belongs to this class.
342 * @pm: The default device power management operations of this class.
343 * @p: The private data of the driver core, no one other than the
344 * driver core can touch this.
346 * A class is a higher-level view of a device that abstracts out low-level
347 * implementation details. Drivers may see a SCSI disk or an ATA disk, but,
348 * at the class level, they are all simply disks. Classes allow user space
349 * to work with devices based on what they do, rather than how they are
350 * connected or how they work.
354 struct module *owner;
356 struct class_attribute *class_attrs;
357 const struct attribute_group **dev_groups;
358 struct kobject *dev_kobj;
360 int (*dev_uevent)(struct device *dev, struct kobj_uevent_env *env);
361 char *(*devnode)(struct device *dev, umode_t *mode);
363 void (*class_release)(struct class *class);
364 void (*dev_release)(struct device *dev);
366 int (*suspend)(struct device *dev, pm_message_t state);
367 int (*resume)(struct device *dev);
369 const struct kobj_ns_type_operations *ns_type;
370 const void *(*namespace)(struct device *dev);
372 const struct dev_pm_ops *pm;
374 struct subsys_private *p;
377 struct class_dev_iter {
378 struct klist_iter ki;
379 const struct device_type *type;
382 extern struct kobject *sysfs_dev_block_kobj;
383 extern struct kobject *sysfs_dev_char_kobj;
384 extern int __must_check __class_register(struct class *class,
385 struct lock_class_key *key);
386 extern void class_unregister(struct class *class);
388 /* This is a #define to keep the compiler from merging different
389 * instances of the __key variable */
390 #define class_register(class) \
392 static struct lock_class_key __key; \
393 __class_register(class, &__key); \
397 struct class_compat *class_compat_register(const char *name);
398 void class_compat_unregister(struct class_compat *cls);
399 int class_compat_create_link(struct class_compat *cls, struct device *dev,
400 struct device *device_link);
401 void class_compat_remove_link(struct class_compat *cls, struct device *dev,
402 struct device *device_link);
404 extern void class_dev_iter_init(struct class_dev_iter *iter,
406 struct device *start,
407 const struct device_type *type);
408 extern struct device *class_dev_iter_next(struct class_dev_iter *iter);
409 extern void class_dev_iter_exit(struct class_dev_iter *iter);
411 extern int class_for_each_device(struct class *class, struct device *start,
413 int (*fn)(struct device *dev, void *data));
414 extern struct device *class_find_device(struct class *class,
415 struct device *start, const void *data,
416 int (*match)(struct device *, const void *));
418 struct class_attribute {
419 struct attribute attr;
420 ssize_t (*show)(struct class *class, struct class_attribute *attr,
422 ssize_t (*store)(struct class *class, struct class_attribute *attr,
423 const char *buf, size_t count);
426 #define CLASS_ATTR(_name, _mode, _show, _store) \
427 struct class_attribute class_attr_##_name = __ATTR(_name, _mode, _show, _store)
428 #define CLASS_ATTR_RW(_name) \
429 struct class_attribute class_attr_##_name = __ATTR_RW(_name)
430 #define CLASS_ATTR_RO(_name) \
431 struct class_attribute class_attr_##_name = __ATTR_RO(_name)
433 extern int __must_check class_create_file_ns(struct class *class,
434 const struct class_attribute *attr,
436 extern void class_remove_file_ns(struct class *class,
437 const struct class_attribute *attr,
440 static inline int __must_check class_create_file(struct class *class,
441 const struct class_attribute *attr)
443 return class_create_file_ns(class, attr, NULL);
446 static inline void class_remove_file(struct class *class,
447 const struct class_attribute *attr)
449 return class_remove_file_ns(class, attr, NULL);
452 /* Simple class attribute that is just a static string */
453 struct class_attribute_string {
454 struct class_attribute attr;
458 /* Currently read-only only */
459 #define _CLASS_ATTR_STRING(_name, _mode, _str) \
460 { __ATTR(_name, _mode, show_class_attr_string, NULL), _str }
461 #define CLASS_ATTR_STRING(_name, _mode, _str) \
462 struct class_attribute_string class_attr_##_name = \
463 _CLASS_ATTR_STRING(_name, _mode, _str)
465 extern ssize_t show_class_attr_string(struct class *class, struct class_attribute *attr,
468 struct class_interface {
469 struct list_head node;
472 int (*add_dev) (struct device *, struct class_interface *);
473 void (*remove_dev) (struct device *, struct class_interface *);
476 extern int __must_check class_interface_register(struct class_interface *);
477 extern void class_interface_unregister(struct class_interface *);
479 extern struct class * __must_check __class_create(struct module *owner,
481 struct lock_class_key *key);
482 extern void class_destroy(struct class *cls);
484 /* This is a #define to keep the compiler from merging different
485 * instances of the __key variable */
486 #define class_create(owner, name) \
488 static struct lock_class_key __key; \
489 __class_create(owner, name, &__key); \
493 * The type of device, "struct device" is embedded in. A class
494 * or bus can contain devices of different types
495 * like "partitions" and "disks", "mouse" and "event".
496 * This identifies the device type and carries type-specific
497 * information, equivalent to the kobj_type of a kobject.
498 * If "name" is specified, the uevent will contain it in
499 * the DEVTYPE variable.
503 const struct attribute_group **groups;
504 int (*uevent)(struct device *dev, struct kobj_uevent_env *env);
505 char *(*devnode)(struct device *dev, umode_t *mode,
506 kuid_t *uid, kgid_t *gid);
507 void (*release)(struct device *dev);
509 const struct dev_pm_ops *pm;
512 /* interface for exporting device attributes */
513 struct device_attribute {
514 struct attribute attr;
515 ssize_t (*show)(struct device *dev, struct device_attribute *attr,
517 ssize_t (*store)(struct device *dev, struct device_attribute *attr,
518 const char *buf, size_t count);
521 struct dev_ext_attribute {
522 struct device_attribute attr;
526 ssize_t device_show_ulong(struct device *dev, struct device_attribute *attr,
528 ssize_t device_store_ulong(struct device *dev, struct device_attribute *attr,
529 const char *buf, size_t count);
530 ssize_t device_show_int(struct device *dev, struct device_attribute *attr,
532 ssize_t device_store_int(struct device *dev, struct device_attribute *attr,
533 const char *buf, size_t count);
534 ssize_t device_show_bool(struct device *dev, struct device_attribute *attr,
536 ssize_t device_store_bool(struct device *dev, struct device_attribute *attr,
537 const char *buf, size_t count);
539 #define DEVICE_ATTR(_name, _mode, _show, _store) \
540 struct device_attribute dev_attr_##_name = __ATTR(_name, _mode, _show, _store)
541 #define DEVICE_ATTR_RW(_name) \
542 struct device_attribute dev_attr_##_name = __ATTR_RW(_name)
543 #define DEVICE_ATTR_RO(_name) \
544 struct device_attribute dev_attr_##_name = __ATTR_RO(_name)
545 #define DEVICE_ATTR_WO(_name) \
546 struct device_attribute dev_attr_##_name = __ATTR_WO(_name)
547 #define DEVICE_ULONG_ATTR(_name, _mode, _var) \
548 struct dev_ext_attribute dev_attr_##_name = \
549 { __ATTR(_name, _mode, device_show_ulong, device_store_ulong), &(_var) }
550 #define DEVICE_INT_ATTR(_name, _mode, _var) \
551 struct dev_ext_attribute dev_attr_##_name = \
552 { __ATTR(_name, _mode, device_show_int, device_store_int), &(_var) }
553 #define DEVICE_BOOL_ATTR(_name, _mode, _var) \
554 struct dev_ext_attribute dev_attr_##_name = \
555 { __ATTR(_name, _mode, device_show_bool, device_store_bool), &(_var) }
556 #define DEVICE_ATTR_IGNORE_LOCKDEP(_name, _mode, _show, _store) \
557 struct device_attribute dev_attr_##_name = \
558 __ATTR_IGNORE_LOCKDEP(_name, _mode, _show, _store)
560 extern int device_create_file(struct device *device,
561 const struct device_attribute *entry);
562 extern void device_remove_file(struct device *dev,
563 const struct device_attribute *attr);
564 extern bool device_remove_file_self(struct device *dev,
565 const struct device_attribute *attr);
566 extern int __must_check device_create_bin_file(struct device *dev,
567 const struct bin_attribute *attr);
568 extern void device_remove_bin_file(struct device *dev,
569 const struct bin_attribute *attr);
571 /* device resource management */
572 typedef void (*dr_release_t)(struct device *dev, void *res);
573 typedef int (*dr_match_t)(struct device *dev, void *res, void *match_data);
575 #ifdef CONFIG_DEBUG_DEVRES
576 extern void *__devres_alloc(dr_release_t release, size_t size, gfp_t gfp,
578 #define devres_alloc(release, size, gfp) \
579 __devres_alloc(release, size, gfp, #release)
581 extern void *devres_alloc(dr_release_t release, size_t size, gfp_t gfp);
583 extern void devres_for_each_res(struct device *dev, dr_release_t release,
584 dr_match_t match, void *match_data,
585 void (*fn)(struct device *, void *, void *),
587 extern void devres_free(void *res);
588 extern void devres_add(struct device *dev, void *res);
589 extern void *devres_find(struct device *dev, dr_release_t release,
590 dr_match_t match, void *match_data);
591 extern void *devres_get(struct device *dev, void *new_res,
592 dr_match_t match, void *match_data);
593 extern void *devres_remove(struct device *dev, dr_release_t release,
594 dr_match_t match, void *match_data);
595 extern int devres_destroy(struct device *dev, dr_release_t release,
596 dr_match_t match, void *match_data);
597 extern int devres_release(struct device *dev, dr_release_t release,
598 dr_match_t match, void *match_data);
601 extern void * __must_check devres_open_group(struct device *dev, void *id,
603 extern void devres_close_group(struct device *dev, void *id);
604 extern void devres_remove_group(struct device *dev, void *id);
605 extern int devres_release_group(struct device *dev, void *id);
607 /* managed devm_k.alloc/kfree for device drivers */
608 extern void *devm_kmalloc(struct device *dev, size_t size, gfp_t gfp);
609 extern char *devm_kvasprintf(struct device *dev, gfp_t gfp, const char *fmt,
611 extern __printf(3, 4)
612 char *devm_kasprintf(struct device *dev, gfp_t gfp, const char *fmt, ...);
613 static inline void *devm_kzalloc(struct device *dev, size_t size, gfp_t gfp)
615 return devm_kmalloc(dev, size, gfp | __GFP_ZERO);
617 static inline void *devm_kmalloc_array(struct device *dev,
618 size_t n, size_t size, gfp_t flags)
620 if (size != 0 && n > SIZE_MAX / size)
622 return devm_kmalloc(dev, n * size, flags);
624 static inline void *devm_kcalloc(struct device *dev,
625 size_t n, size_t size, gfp_t flags)
627 return devm_kmalloc_array(dev, n, size, flags | __GFP_ZERO);
629 extern void devm_kfree(struct device *dev, void *p);
630 extern char *devm_kstrdup(struct device *dev, const char *s, gfp_t gfp);
631 extern void *devm_kmemdup(struct device *dev, const void *src, size_t len,
634 extern unsigned long devm_get_free_pages(struct device *dev,
635 gfp_t gfp_mask, unsigned int order);
636 extern void devm_free_pages(struct device *dev, unsigned long addr);
638 void __iomem *devm_ioremap_resource(struct device *dev, struct resource *res);
640 /* allows to add/remove a custom action to devres stack */
641 int devm_add_action(struct device *dev, void (*action)(void *), void *data);
642 void devm_remove_action(struct device *dev, void (*action)(void *), void *data);
644 struct device_dma_parameters {
646 * a low level driver may set these to teach IOMMU code about
649 unsigned int max_segment_size;
650 unsigned long segment_boundary_mask;
655 struct acpi_dev_node {
657 struct acpi_device *companion;
662 * struct device - The basic device structure
663 * @parent: The device's "parent" device, the device to which it is attached.
664 * In most cases, a parent device is some sort of bus or host
665 * controller. If parent is NULL, the device, is a top-level device,
666 * which is not usually what you want.
667 * @p: Holds the private data of the driver core portions of the device.
668 * See the comment of the struct device_private for detail.
669 * @kobj: A top-level, abstract class from which other classes are derived.
670 * @init_name: Initial name of the device.
671 * @type: The type of device.
672 * This identifies the device type and carries type-specific
674 * @mutex: Mutex to synchronize calls to its driver.
675 * @bus: Type of bus device is on.
676 * @driver: Which driver has allocated this
677 * @platform_data: Platform data specific to the device.
678 * Example: For devices on custom boards, as typical of embedded
679 * and SOC based hardware, Linux often uses platform_data to point
680 * to board-specific structures describing devices and how they
681 * are wired. That can include what ports are available, chip
682 * variants, which GPIO pins act in what additional roles, and so
683 * on. This shrinks the "Board Support Packages" (BSPs) and
684 * minimizes board-specific #ifdefs in drivers.
685 * @driver_data: Private pointer for driver specific info.
686 * @power: For device power management.
687 * See Documentation/power/devices.txt for details.
688 * @pm_domain: Provide callbacks that are executed during system suspend,
689 * hibernation, system resume and during runtime PM transitions
690 * along with subsystem-level and driver-level callbacks.
691 * @pins: For device pin management.
692 * See Documentation/pinctrl.txt for details.
693 * @numa_node: NUMA node this device is close to.
694 * @dma_mask: Dma mask (if dma'ble device).
695 * @coherent_dma_mask: Like dma_mask, but for alloc_coherent mapping as not all
696 * hardware supports 64-bit addresses for consistent allocations
698 * @dma_pfn_offset: offset of DMA memory range relatively of RAM
699 * @dma_parms: A low level driver may set these to teach IOMMU code about
700 * segment limitations.
701 * @dma_pools: Dma pools (if dma'ble device).
702 * @dma_mem: Internal for coherent mem override.
703 * @cma_area: Contiguous memory area for dma allocations
704 * @archdata: For arch-specific additions.
705 * @of_node: Associated device tree node.
706 * @acpi_node: Associated ACPI device node.
707 * @devt: For creating the sysfs "dev".
708 * @id: device instance
709 * @devres_lock: Spinlock to protect the resource of the device.
710 * @devres_head: The resources list of the device.
711 * @knode_class: The node used to add the device to the class list.
712 * @class: The class of the device.
713 * @groups: Optional attribute groups.
714 * @release: Callback to free the device after all references have
715 * gone away. This should be set by the allocator of the
716 * device (i.e. the bus driver that discovered the device).
717 * @iommu_group: IOMMU group the device belongs to.
719 * @offline_disabled: If set, the device is permanently online.
720 * @offline: Set after successful invocation of bus type's .offline().
722 * At the lowest level, every device in a Linux system is represented by an
723 * instance of struct device. The device structure contains the information
724 * that the device model core needs to model the system. Most subsystems,
725 * however, track additional information about the devices they host. As a
726 * result, it is rare for devices to be represented by bare device structures;
727 * instead, that structure, like kobject structures, is usually embedded within
728 * a higher-level representation of the device.
731 struct device *parent;
733 struct device_private *p;
736 const char *init_name; /* initial name of the device */
737 const struct device_type *type;
739 struct mutex mutex; /* mutex to synchronize calls to
743 struct bus_type *bus; /* type of bus device is on */
744 struct device_driver *driver; /* which driver has allocated this
746 void *platform_data; /* Platform specific data, device
747 core doesn't touch it */
748 void *driver_data; /* Driver data, set and get with
749 dev_set/get_drvdata */
750 struct dev_pm_info power;
751 struct dev_pm_domain *pm_domain;
753 #ifdef CONFIG_PINCTRL
754 struct dev_pin_info *pins;
758 int numa_node; /* NUMA node this device is close to */
760 u64 *dma_mask; /* dma mask (if dma'able device) */
761 u64 coherent_dma_mask;/* Like dma_mask, but for
762 alloc_coherent mappings as
763 not all hardware supports
764 64 bit addresses for consistent
765 allocations such descriptors. */
766 unsigned long dma_pfn_offset;
768 struct device_dma_parameters *dma_parms;
770 struct list_head dma_pools; /* dma pools (if dma'ble) */
772 struct dma_coherent_mem *dma_mem; /* internal for coherent mem
774 #ifdef CONFIG_DMA_CMA
775 struct cma *cma_area; /* contiguous memory area for dma
778 /* arch specific additions */
779 struct dev_archdata archdata;
781 struct device_node *of_node; /* associated device tree node */
782 struct acpi_dev_node acpi_node; /* associated ACPI device node */
784 dev_t devt; /* dev_t, creates the sysfs "dev" */
785 u32 id; /* device instance */
787 spinlock_t devres_lock;
788 struct list_head devres_head;
790 struct klist_node knode_class;
792 const struct attribute_group **groups; /* optional groups */
794 void (*release)(struct device *dev);
795 struct iommu_group *iommu_group;
797 bool offline_disabled:1;
801 static inline struct device *kobj_to_dev(struct kobject *kobj)
803 return container_of(kobj, struct device, kobj);
806 /* Get the wakeup routines, which depend on struct device */
807 #include <linux/pm_wakeup.h>
809 static inline const char *dev_name(const struct device *dev)
811 /* Use the init name until the kobject becomes available */
813 return dev->init_name;
815 return kobject_name(&dev->kobj);
818 extern __printf(2, 3)
819 int dev_set_name(struct device *dev, const char *name, ...);
822 static inline int dev_to_node(struct device *dev)
824 return dev->numa_node;
826 static inline void set_dev_node(struct device *dev, int node)
828 dev->numa_node = node;
831 static inline int dev_to_node(struct device *dev)
835 static inline void set_dev_node(struct device *dev, int node)
840 static inline void *dev_get_drvdata(const struct device *dev)
842 return dev->driver_data;
845 static inline void dev_set_drvdata(struct device *dev, void *data)
847 dev->driver_data = data;
850 static inline struct pm_subsys_data *dev_to_psd(struct device *dev)
852 return dev ? dev->power.subsys_data : NULL;
855 static inline unsigned int dev_get_uevent_suppress(const struct device *dev)
857 return dev->kobj.uevent_suppress;
860 static inline void dev_set_uevent_suppress(struct device *dev, int val)
862 dev->kobj.uevent_suppress = val;
865 static inline int device_is_registered(struct device *dev)
867 return dev->kobj.state_in_sysfs;
870 static inline void device_enable_async_suspend(struct device *dev)
872 if (!dev->power.is_prepared)
873 dev->power.async_suspend = true;
876 static inline void device_disable_async_suspend(struct device *dev)
878 if (!dev->power.is_prepared)
879 dev->power.async_suspend = false;
882 static inline bool device_async_suspend_enabled(struct device *dev)
884 return !!dev->power.async_suspend;
887 static inline void pm_suspend_ignore_children(struct device *dev, bool enable)
889 dev->power.ignore_children = enable;
892 static inline void dev_pm_syscore_device(struct device *dev, bool val)
894 #ifdef CONFIG_PM_SLEEP
895 dev->power.syscore = val;
899 static inline void device_lock(struct device *dev)
901 mutex_lock(&dev->mutex);
904 static inline int device_trylock(struct device *dev)
906 return mutex_trylock(&dev->mutex);
909 static inline void device_unlock(struct device *dev)
911 mutex_unlock(&dev->mutex);
914 static inline void device_lock_assert(struct device *dev)
916 lockdep_assert_held(&dev->mutex);
919 void driver_init(void);
922 * High level routines for use by the bus drivers
924 extern int __must_check device_register(struct device *dev);
925 extern void device_unregister(struct device *dev);
926 extern void device_initialize(struct device *dev);
927 extern int __must_check device_add(struct device *dev);
928 extern void device_del(struct device *dev);
929 extern int device_for_each_child(struct device *dev, void *data,
930 int (*fn)(struct device *dev, void *data));
931 extern struct device *device_find_child(struct device *dev, void *data,
932 int (*match)(struct device *dev, void *data));
933 extern int device_rename(struct device *dev, const char *new_name);
934 extern int device_move(struct device *dev, struct device *new_parent,
935 enum dpm_order dpm_order);
936 extern const char *device_get_devnode(struct device *dev,
937 umode_t *mode, kuid_t *uid, kgid_t *gid,
940 static inline bool device_supports_offline(struct device *dev)
942 return dev->bus && dev->bus->offline && dev->bus->online;
945 extern void lock_device_hotplug(void);
946 extern void unlock_device_hotplug(void);
947 extern int lock_device_hotplug_sysfs(void);
948 extern int device_offline(struct device *dev);
949 extern int device_online(struct device *dev);
951 * Root device objects for grouping under /sys/devices
953 extern struct device *__root_device_register(const char *name,
954 struct module *owner);
956 /* This is a macro to avoid include problems with THIS_MODULE */
957 #define root_device_register(name) \
958 __root_device_register(name, THIS_MODULE)
960 extern void root_device_unregister(struct device *root);
962 static inline void *dev_get_platdata(const struct device *dev)
964 return dev->platform_data;
968 * Manual binding of a device to driver. See drivers/base/bus.c
969 * for information on use.
971 extern int __must_check device_bind_driver(struct device *dev);
972 extern void device_release_driver(struct device *dev);
973 extern int __must_check device_attach(struct device *dev);
974 extern int __must_check driver_attach(struct device_driver *drv);
975 extern int __must_check device_reprobe(struct device *dev);
978 * Easy functions for dynamically creating devices on the fly
980 extern struct device *device_create_vargs(struct class *cls,
981 struct device *parent,
986 extern __printf(5, 6)
987 struct device *device_create(struct class *cls, struct device *parent,
988 dev_t devt, void *drvdata,
989 const char *fmt, ...);
990 extern __printf(6, 7)
991 struct device *device_create_with_groups(struct class *cls,
992 struct device *parent, dev_t devt, void *drvdata,
993 const struct attribute_group **groups,
994 const char *fmt, ...);
995 extern void device_destroy(struct class *cls, dev_t devt);
998 * Platform "fixup" functions - allow the platform to have their say
999 * about devices and actions that the general device layer doesn't
1002 /* Notify platform of device discovery */
1003 extern int (*platform_notify)(struct device *dev);
1005 extern int (*platform_notify_remove)(struct device *dev);
1009 * get_device - atomically increment the reference count for the device.
1012 extern struct device *get_device(struct device *dev);
1013 extern void put_device(struct device *dev);
1015 #ifdef CONFIG_DEVTMPFS
1016 extern int devtmpfs_create_node(struct device *dev);
1017 extern int devtmpfs_delete_node(struct device *dev);
1018 extern int devtmpfs_mount(const char *mntdir);
1020 static inline int devtmpfs_create_node(struct device *dev) { return 0; }
1021 static inline int devtmpfs_delete_node(struct device *dev) { return 0; }
1022 static inline int devtmpfs_mount(const char *mountpoint) { return 0; }
1025 /* drivers/base/power/shutdown.c */
1026 extern void device_shutdown(void);
1028 /* debugging and troubleshooting/diagnostic helpers. */
1029 extern const char *dev_driver_string(const struct device *dev);
1032 #ifdef CONFIG_PRINTK
1034 extern __printf(3, 0)
1035 int dev_vprintk_emit(int level, const struct device *dev,
1036 const char *fmt, va_list args);
1037 extern __printf(3, 4)
1038 int dev_printk_emit(int level, const struct device *dev, const char *fmt, ...);
1040 extern __printf(3, 4)
1041 int dev_printk(const char *level, const struct device *dev,
1042 const char *fmt, ...);
1043 extern __printf(2, 3)
1044 int dev_emerg(const struct device *dev, const char *fmt, ...);
1045 extern __printf(2, 3)
1046 int dev_alert(const struct device *dev, const char *fmt, ...);
1047 extern __printf(2, 3)
1048 int dev_crit(const struct device *dev, const char *fmt, ...);
1049 extern __printf(2, 3)
1050 int dev_err(const struct device *dev, const char *fmt, ...);
1051 extern __printf(2, 3)
1052 int dev_warn(const struct device *dev, const char *fmt, ...);
1053 extern __printf(2, 3)
1054 int dev_notice(const struct device *dev, const char *fmt, ...);
1055 extern __printf(2, 3)
1056 int _dev_info(const struct device *dev, const char *fmt, ...);
1060 static inline __printf(3, 0)
1061 int dev_vprintk_emit(int level, const struct device *dev,
1062 const char *fmt, va_list args)
1064 static inline __printf(3, 4)
1065 int dev_printk_emit(int level, const struct device *dev, const char *fmt, ...)
1068 static inline int __dev_printk(const char *level, const struct device *dev,
1069 struct va_format *vaf)
1071 static inline __printf(3, 4)
1072 int dev_printk(const char *level, const struct device *dev,
1073 const char *fmt, ...)
1076 static inline __printf(2, 3)
1077 int dev_emerg(const struct device *dev, const char *fmt, ...)
1079 static inline __printf(2, 3)
1080 int dev_crit(const struct device *dev, const char *fmt, ...)
1082 static inline __printf(2, 3)
1083 int dev_alert(const struct device *dev, const char *fmt, ...)
1085 static inline __printf(2, 3)
1086 int dev_err(const struct device *dev, const char *fmt, ...)
1088 static inline __printf(2, 3)
1089 int dev_warn(const struct device *dev, const char *fmt, ...)
1091 static inline __printf(2, 3)
1092 int dev_notice(const struct device *dev, const char *fmt, ...)
1094 static inline __printf(2, 3)
1095 int _dev_info(const struct device *dev, const char *fmt, ...)
1101 * Stupid hackaround for existing uses of non-printk uses dev_info
1103 * Note that the definition of dev_info below is actually _dev_info
1104 * and a macro is used to avoid redefining dev_info
1107 #define dev_info(dev, fmt, arg...) _dev_info(dev, fmt, ##arg)
1109 #if defined(CONFIG_DYNAMIC_DEBUG)
1110 #define dev_dbg(dev, format, ...) \
1112 dynamic_dev_dbg(dev, format, ##__VA_ARGS__); \
1114 #elif defined(DEBUG)
1115 #define dev_dbg(dev, format, arg...) \
1116 dev_printk(KERN_DEBUG, dev, format, ##arg)
1118 #define dev_dbg(dev, format, arg...) \
1121 dev_printk(KERN_DEBUG, dev, format, ##arg); \
1126 #define dev_level_ratelimited(dev_level, dev, fmt, ...) \
1128 static DEFINE_RATELIMIT_STATE(_rs, \
1129 DEFAULT_RATELIMIT_INTERVAL, \
1130 DEFAULT_RATELIMIT_BURST); \
1131 if (__ratelimit(&_rs)) \
1132 dev_level(dev, fmt, ##__VA_ARGS__); \
1135 #define dev_emerg_ratelimited(dev, fmt, ...) \
1136 dev_level_ratelimited(dev_emerg, dev, fmt, ##__VA_ARGS__)
1137 #define dev_alert_ratelimited(dev, fmt, ...) \
1138 dev_level_ratelimited(dev_alert, dev, fmt, ##__VA_ARGS__)
1139 #define dev_crit_ratelimited(dev, fmt, ...) \
1140 dev_level_ratelimited(dev_crit, dev, fmt, ##__VA_ARGS__)
1141 #define dev_err_ratelimited(dev, fmt, ...) \
1142 dev_level_ratelimited(dev_err, dev, fmt, ##__VA_ARGS__)
1143 #define dev_warn_ratelimited(dev, fmt, ...) \
1144 dev_level_ratelimited(dev_warn, dev, fmt, ##__VA_ARGS__)
1145 #define dev_notice_ratelimited(dev, fmt, ...) \
1146 dev_level_ratelimited(dev_notice, dev, fmt, ##__VA_ARGS__)
1147 #define dev_info_ratelimited(dev, fmt, ...) \
1148 dev_level_ratelimited(dev_info, dev, fmt, ##__VA_ARGS__)
1149 #if defined(CONFIG_DYNAMIC_DEBUG)
1150 /* descriptor check is first to prevent flooding with "callbacks suppressed" */
1151 #define dev_dbg_ratelimited(dev, fmt, ...) \
1153 static DEFINE_RATELIMIT_STATE(_rs, \
1154 DEFAULT_RATELIMIT_INTERVAL, \
1155 DEFAULT_RATELIMIT_BURST); \
1156 DEFINE_DYNAMIC_DEBUG_METADATA(descriptor, fmt); \
1157 if (unlikely(descriptor.flags & _DPRINTK_FLAGS_PRINT) && \
1158 __ratelimit(&_rs)) \
1159 __dynamic_dev_dbg(&descriptor, dev, fmt, \
1162 #elif defined(DEBUG)
1163 #define dev_dbg_ratelimited(dev, fmt, ...) \
1165 static DEFINE_RATELIMIT_STATE(_rs, \
1166 DEFAULT_RATELIMIT_INTERVAL, \
1167 DEFAULT_RATELIMIT_BURST); \
1168 if (__ratelimit(&_rs)) \
1169 dev_printk(KERN_DEBUG, dev, fmt, ##__VA_ARGS__); \
1172 #define dev_dbg_ratelimited(dev, fmt, ...) \
1173 no_printk(KERN_DEBUG pr_fmt(fmt), ##__VA_ARGS__)
1176 #ifdef VERBOSE_DEBUG
1177 #define dev_vdbg dev_dbg
1179 #define dev_vdbg(dev, format, arg...) \
1182 dev_printk(KERN_DEBUG, dev, format, ##arg); \
1188 * dev_WARN*() acts like dev_printk(), but with the key difference of
1189 * using WARN/WARN_ONCE to include file/line information and a backtrace.
1191 #define dev_WARN(dev, format, arg...) \
1192 WARN(1, "%s %s: " format, dev_driver_string(dev), dev_name(dev), ## arg);
1194 #define dev_WARN_ONCE(dev, condition, format, arg...) \
1195 WARN_ONCE(condition, "%s %s: " format, \
1196 dev_driver_string(dev), dev_name(dev), ## arg)
1198 /* Create alias, so I can be autoloaded. */
1199 #define MODULE_ALIAS_CHARDEV(major,minor) \
1200 MODULE_ALIAS("char-major-" __stringify(major) "-" __stringify(minor))
1201 #define MODULE_ALIAS_CHARDEV_MAJOR(major) \
1202 MODULE_ALIAS("char-major-" __stringify(major) "-*")
1204 #ifdef CONFIG_SYSFS_DEPRECATED
1205 extern long sysfs_deprecated;
1207 #define sysfs_deprecated 0
1211 * module_driver() - Helper macro for drivers that don't do anything
1212 * special in module init/exit. This eliminates a lot of boilerplate.
1213 * Each module may only use this macro once, and calling it replaces
1214 * module_init() and module_exit().
1216 * @__driver: driver name
1217 * @__register: register function for this driver type
1218 * @__unregister: unregister function for this driver type
1219 * @...: Additional arguments to be passed to __register and __unregister.
1221 * Use this macro to construct bus specific macros for registering
1222 * drivers, and do not use it on its own.
1224 #define module_driver(__driver, __register, __unregister, ...) \
1225 static int __init __driver##_init(void) \
1227 return __register(&(__driver) , ##__VA_ARGS__); \
1229 module_init(__driver##_init); \
1230 static void __exit __driver##_exit(void) \
1232 __unregister(&(__driver) , ##__VA_ARGS__); \
1234 module_exit(__driver##_exit);
1236 #endif /* _DEVICE_H_ */