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 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 removed */
185 #define BUS_NOTIFY_BIND_DRIVER 0x00000003 /* driver about to be
187 #define BUS_NOTIFY_BOUND_DRIVER 0x00000004 /* driver bound to device */
188 #define BUS_NOTIFY_UNBIND_DRIVER 0x00000005 /* driver about to be
190 #define BUS_NOTIFY_UNBOUND_DRIVER 0x00000006 /* driver is unbound
193 extern struct kset *bus_get_kset(struct bus_type *bus);
194 extern struct klist *bus_get_device_klist(struct bus_type *bus);
197 * struct device_driver - The basic device driver structure
198 * @name: Name of the device driver.
199 * @bus: The bus which the device of this driver belongs to.
200 * @owner: The module owner.
201 * @mod_name: Used for built-in modules.
202 * @suppress_bind_attrs: Disables bind/unbind via sysfs.
203 * @of_match_table: The open firmware table.
204 * @acpi_match_table: The ACPI match table.
205 * @probe: Called to query the existence of a specific device,
206 * whether this driver can work with it, and bind the driver
207 * to a specific device.
208 * @remove: Called when the device is removed from the system to
209 * unbind a device from this driver.
210 * @shutdown: Called at shut-down time to quiesce the device.
211 * @suspend: Called to put the device to sleep mode. Usually to a
213 * @resume: Called to bring a device from sleep mode.
214 * @groups: Default attributes that get created by the driver core
216 * @pm: Power management operations of the device which matched
218 * @p: Driver core's private data, no one other than the driver
219 * core can touch this.
221 * The device driver-model tracks all of the drivers known to the system.
222 * The main reason for this tracking is to enable the driver core to match
223 * up drivers with new devices. Once drivers are known objects within the
224 * system, however, a number of other things become possible. Device drivers
225 * can export information and configuration variables that are independent
226 * of any specific device.
228 struct device_driver {
230 struct bus_type *bus;
232 struct module *owner;
233 const char *mod_name; /* used for built-in modules */
235 bool suppress_bind_attrs; /* disables bind/unbind via sysfs */
237 const struct of_device_id *of_match_table;
238 const struct acpi_device_id *acpi_match_table;
240 int (*probe) (struct device *dev);
241 int (*remove) (struct device *dev);
242 void (*shutdown) (struct device *dev);
243 int (*suspend) (struct device *dev, pm_message_t state);
244 int (*resume) (struct device *dev);
245 const struct attribute_group **groups;
247 const struct dev_pm_ops *pm;
249 struct driver_private *p;
253 extern int __must_check driver_register(struct device_driver *drv);
254 extern void driver_unregister(struct device_driver *drv);
256 extern struct device_driver *driver_find(const char *name,
257 struct bus_type *bus);
258 extern int driver_probe_done(void);
259 extern void wait_for_device_probe(void);
262 /* sysfs interface for exporting driver attributes */
264 struct driver_attribute {
265 struct attribute attr;
266 ssize_t (*show)(struct device_driver *driver, char *buf);
267 ssize_t (*store)(struct device_driver *driver, const char *buf,
271 #define DRIVER_ATTR(_name, _mode, _show, _store) \
272 struct driver_attribute driver_attr_##_name = __ATTR(_name, _mode, _show, _store)
273 #define DRIVER_ATTR_RW(_name) \
274 struct driver_attribute driver_attr_##_name = __ATTR_RW(_name)
275 #define DRIVER_ATTR_RO(_name) \
276 struct driver_attribute driver_attr_##_name = __ATTR_RO(_name)
277 #define DRIVER_ATTR_WO(_name) \
278 struct driver_attribute driver_attr_##_name = __ATTR_WO(_name)
280 extern int __must_check driver_create_file(struct device_driver *driver,
281 const struct driver_attribute *attr);
282 extern void driver_remove_file(struct device_driver *driver,
283 const struct driver_attribute *attr);
285 extern int __must_check driver_for_each_device(struct device_driver *drv,
286 struct device *start,
288 int (*fn)(struct device *dev,
290 struct device *driver_find_device(struct device_driver *drv,
291 struct device *start, void *data,
292 int (*match)(struct device *dev, void *data));
295 * struct subsys_interface - interfaces to device functions
296 * @name: name of the device function
297 * @subsys: subsytem of the devices to attach to
298 * @node: the list of functions registered at the subsystem
299 * @add_dev: device hookup to device function handler
300 * @remove_dev: device hookup to device function handler
302 * Simple interfaces attached to a subsystem. Multiple interfaces can
303 * attach to a subsystem and its devices. Unlike drivers, they do not
304 * exclusively claim or control devices. Interfaces usually represent
305 * a specific functionality of a subsystem/class of devices.
307 struct subsys_interface {
309 struct bus_type *subsys;
310 struct list_head node;
311 int (*add_dev)(struct device *dev, struct subsys_interface *sif);
312 int (*remove_dev)(struct device *dev, struct subsys_interface *sif);
315 int subsys_interface_register(struct subsys_interface *sif);
316 void subsys_interface_unregister(struct subsys_interface *sif);
318 int subsys_system_register(struct bus_type *subsys,
319 const struct attribute_group **groups);
320 int subsys_virtual_register(struct bus_type *subsys,
321 const struct attribute_group **groups);
324 * struct class - device classes
325 * @name: Name of the class.
326 * @owner: The module owner.
327 * @class_attrs: Default attributes of this class.
328 * @dev_groups: Default attributes of the devices that belong to the class.
329 * @dev_kobj: The kobject that represents this class and links it into the hierarchy.
330 * @dev_uevent: Called when a device is added, removed from this class, or a
331 * few other things that generate uevents to add the environment
333 * @devnode: Callback to provide the devtmpfs.
334 * @class_release: Called to release this class.
335 * @dev_release: Called to release the device.
336 * @suspend: Used to put the device to sleep mode, usually to a low power
338 * @resume: Used to bring the device from the sleep mode.
339 * @ns_type: Callbacks so sysfs can detemine namespaces.
340 * @namespace: Namespace of the device belongs to this class.
341 * @pm: The default device power management operations of this class.
342 * @p: The private data of the driver core, no one other than the
343 * driver core can touch this.
345 * A class is a higher-level view of a device that abstracts out low-level
346 * implementation details. Drivers may see a SCSI disk or an ATA disk, but,
347 * at the class level, they are all simply disks. Classes allow user space
348 * to work with devices based on what they do, rather than how they are
349 * connected or how they work.
353 struct module *owner;
355 struct class_attribute *class_attrs;
356 const struct attribute_group **dev_groups;
357 struct kobject *dev_kobj;
359 int (*dev_uevent)(struct device *dev, struct kobj_uevent_env *env);
360 char *(*devnode)(struct device *dev, umode_t *mode);
362 void (*class_release)(struct class *class);
363 void (*dev_release)(struct device *dev);
365 int (*suspend)(struct device *dev, pm_message_t state);
366 int (*resume)(struct device *dev);
368 const struct kobj_ns_type_operations *ns_type;
369 const void *(*namespace)(struct device *dev);
371 const struct dev_pm_ops *pm;
373 struct subsys_private *p;
376 struct class_dev_iter {
377 struct klist_iter ki;
378 const struct device_type *type;
381 extern struct kobject *sysfs_dev_block_kobj;
382 extern struct kobject *sysfs_dev_char_kobj;
383 extern int __must_check __class_register(struct class *class,
384 struct lock_class_key *key);
385 extern void class_unregister(struct class *class);
387 /* This is a #define to keep the compiler from merging different
388 * instances of the __key variable */
389 #define class_register(class) \
391 static struct lock_class_key __key; \
392 __class_register(class, &__key); \
396 struct class_compat *class_compat_register(const char *name);
397 void class_compat_unregister(struct class_compat *cls);
398 int class_compat_create_link(struct class_compat *cls, struct device *dev,
399 struct device *device_link);
400 void class_compat_remove_link(struct class_compat *cls, struct device *dev,
401 struct device *device_link);
403 extern void class_dev_iter_init(struct class_dev_iter *iter,
405 struct device *start,
406 const struct device_type *type);
407 extern struct device *class_dev_iter_next(struct class_dev_iter *iter);
408 extern void class_dev_iter_exit(struct class_dev_iter *iter);
410 extern int class_for_each_device(struct class *class, struct device *start,
412 int (*fn)(struct device *dev, void *data));
413 extern struct device *class_find_device(struct class *class,
414 struct device *start, const void *data,
415 int (*match)(struct device *, const void *));
417 struct class_attribute {
418 struct attribute attr;
419 ssize_t (*show)(struct class *class, struct class_attribute *attr,
421 ssize_t (*store)(struct class *class, struct class_attribute *attr,
422 const char *buf, size_t count);
425 #define CLASS_ATTR(_name, _mode, _show, _store) \
426 struct class_attribute class_attr_##_name = __ATTR(_name, _mode, _show, _store)
427 #define CLASS_ATTR_RW(_name) \
428 struct class_attribute class_attr_##_name = __ATTR_RW(_name)
429 #define CLASS_ATTR_RO(_name) \
430 struct class_attribute class_attr_##_name = __ATTR_RO(_name)
432 extern int __must_check class_create_file_ns(struct class *class,
433 const struct class_attribute *attr,
435 extern void class_remove_file_ns(struct class *class,
436 const struct class_attribute *attr,
439 static inline int __must_check class_create_file(struct class *class,
440 const struct class_attribute *attr)
442 return class_create_file_ns(class, attr, NULL);
445 static inline void class_remove_file(struct class *class,
446 const struct class_attribute *attr)
448 return class_remove_file_ns(class, attr, NULL);
451 /* Simple class attribute that is just a static string */
452 struct class_attribute_string {
453 struct class_attribute attr;
457 /* Currently read-only only */
458 #define _CLASS_ATTR_STRING(_name, _mode, _str) \
459 { __ATTR(_name, _mode, show_class_attr_string, NULL), _str }
460 #define CLASS_ATTR_STRING(_name, _mode, _str) \
461 struct class_attribute_string class_attr_##_name = \
462 _CLASS_ATTR_STRING(_name, _mode, _str)
464 extern ssize_t show_class_attr_string(struct class *class, struct class_attribute *attr,
467 struct class_interface {
468 struct list_head node;
471 int (*add_dev) (struct device *, struct class_interface *);
472 void (*remove_dev) (struct device *, struct class_interface *);
475 extern int __must_check class_interface_register(struct class_interface *);
476 extern void class_interface_unregister(struct class_interface *);
478 extern struct class * __must_check __class_create(struct module *owner,
480 struct lock_class_key *key);
481 extern void class_destroy(struct class *cls);
483 /* This is a #define to keep the compiler from merging different
484 * instances of the __key variable */
485 #define class_create(owner, name) \
487 static struct lock_class_key __key; \
488 __class_create(owner, name, &__key); \
492 * The type of device, "struct device" is embedded in. A class
493 * or bus can contain devices of different types
494 * like "partitions" and "disks", "mouse" and "event".
495 * This identifies the device type and carries type-specific
496 * information, equivalent to the kobj_type of a kobject.
497 * If "name" is specified, the uevent will contain it in
498 * the DEVTYPE variable.
502 const struct attribute_group **groups;
503 int (*uevent)(struct device *dev, struct kobj_uevent_env *env);
504 char *(*devnode)(struct device *dev, umode_t *mode,
505 kuid_t *uid, kgid_t *gid);
506 void (*release)(struct device *dev);
508 const struct dev_pm_ops *pm;
511 /* interface for exporting device attributes */
512 struct device_attribute {
513 struct attribute attr;
514 ssize_t (*show)(struct device *dev, struct device_attribute *attr,
516 ssize_t (*store)(struct device *dev, struct device_attribute *attr,
517 const char *buf, size_t count);
520 struct dev_ext_attribute {
521 struct device_attribute attr;
525 ssize_t device_show_ulong(struct device *dev, struct device_attribute *attr,
527 ssize_t device_store_ulong(struct device *dev, struct device_attribute *attr,
528 const char *buf, size_t count);
529 ssize_t device_show_int(struct device *dev, struct device_attribute *attr,
531 ssize_t device_store_int(struct device *dev, struct device_attribute *attr,
532 const char *buf, size_t count);
533 ssize_t device_show_bool(struct device *dev, struct device_attribute *attr,
535 ssize_t device_store_bool(struct device *dev, struct device_attribute *attr,
536 const char *buf, size_t count);
538 #define DEVICE_ATTR(_name, _mode, _show, _store) \
539 struct device_attribute dev_attr_##_name = __ATTR(_name, _mode, _show, _store)
540 #define DEVICE_ATTR_RW(_name) \
541 struct device_attribute dev_attr_##_name = __ATTR_RW(_name)
542 #define DEVICE_ATTR_RO(_name) \
543 struct device_attribute dev_attr_##_name = __ATTR_RO(_name)
544 #define DEVICE_ATTR_WO(_name) \
545 struct device_attribute dev_attr_##_name = __ATTR_WO(_name)
546 #define DEVICE_ULONG_ATTR(_name, _mode, _var) \
547 struct dev_ext_attribute dev_attr_##_name = \
548 { __ATTR(_name, _mode, device_show_ulong, device_store_ulong), &(_var) }
549 #define DEVICE_INT_ATTR(_name, _mode, _var) \
550 struct dev_ext_attribute dev_attr_##_name = \
551 { __ATTR(_name, _mode, device_show_int, device_store_int), &(_var) }
552 #define DEVICE_BOOL_ATTR(_name, _mode, _var) \
553 struct dev_ext_attribute dev_attr_##_name = \
554 { __ATTR(_name, _mode, device_show_bool, device_store_bool), &(_var) }
555 #define DEVICE_ATTR_IGNORE_LOCKDEP(_name, _mode, _show, _store) \
556 struct device_attribute dev_attr_##_name = \
557 __ATTR_IGNORE_LOCKDEP(_name, _mode, _show, _store)
559 extern int device_create_file(struct device *device,
560 const struct device_attribute *entry);
561 extern void device_remove_file(struct device *dev,
562 const struct device_attribute *attr);
563 extern int __must_check device_create_bin_file(struct device *dev,
564 const struct bin_attribute *attr);
565 extern void device_remove_bin_file(struct device *dev,
566 const struct bin_attribute *attr);
567 extern int device_schedule_callback_owner(struct device *dev,
568 void (*func)(struct device *dev), struct module *owner);
570 /* This is a macro to avoid include problems with THIS_MODULE */
571 #define device_schedule_callback(dev, func) \
572 device_schedule_callback_owner(dev, func, THIS_MODULE)
574 /* device resource management */
575 typedef void (*dr_release_t)(struct device *dev, void *res);
576 typedef int (*dr_match_t)(struct device *dev, void *res, void *match_data);
578 #ifdef CONFIG_DEBUG_DEVRES
579 extern void *__devres_alloc(dr_release_t release, size_t size, gfp_t gfp,
581 #define devres_alloc(release, size, gfp) \
582 __devres_alloc(release, size, gfp, #release)
584 extern void *devres_alloc(dr_release_t release, size_t size, gfp_t gfp);
586 extern void devres_for_each_res(struct device *dev, dr_release_t release,
587 dr_match_t match, void *match_data,
588 void (*fn)(struct device *, void *, void *),
590 extern void devres_free(void *res);
591 extern void devres_add(struct device *dev, void *res);
592 extern void *devres_find(struct device *dev, dr_release_t release,
593 dr_match_t match, void *match_data);
594 extern void *devres_get(struct device *dev, void *new_res,
595 dr_match_t match, void *match_data);
596 extern void *devres_remove(struct device *dev, dr_release_t release,
597 dr_match_t match, void *match_data);
598 extern int devres_destroy(struct device *dev, dr_release_t release,
599 dr_match_t match, void *match_data);
600 extern int devres_release(struct device *dev, dr_release_t release,
601 dr_match_t match, void *match_data);
604 extern void * __must_check devres_open_group(struct device *dev, void *id,
606 extern void devres_close_group(struct device *dev, void *id);
607 extern void devres_remove_group(struct device *dev, void *id);
608 extern int devres_release_group(struct device *dev, void *id);
610 /* managed devm_k.alloc/kfree for device drivers */
611 extern void *devm_kmalloc(struct device *dev, size_t size, gfp_t gfp);
612 static inline void *devm_kzalloc(struct device *dev, size_t size, gfp_t gfp)
614 return devm_kmalloc(dev, size, gfp | __GFP_ZERO);
616 static inline void *devm_kmalloc_array(struct device *dev,
617 size_t n, size_t size, gfp_t flags)
619 if (size != 0 && n > SIZE_MAX / size)
621 return devm_kmalloc(dev, n * size, flags);
623 static inline void *devm_kcalloc(struct device *dev,
624 size_t n, size_t size, gfp_t flags)
626 return devm_kmalloc_array(dev, n, size, flags | __GFP_ZERO);
628 extern void devm_kfree(struct device *dev, void *p);
630 void __iomem *devm_ioremap_resource(struct device *dev, struct resource *res);
631 void __iomem *devm_request_and_ioremap(struct device *dev,
632 struct resource *res);
634 /* allows to add/remove a custom action to devres stack */
635 int devm_add_action(struct device *dev, void (*action)(void *), void *data);
636 void devm_remove_action(struct device *dev, void (*action)(void *), void *data);
638 struct device_dma_parameters {
640 * a low level driver may set these to teach IOMMU code about
643 unsigned int max_segment_size;
644 unsigned long segment_boundary_mask;
649 struct acpi_dev_node {
651 struct acpi_device *companion;
656 * struct device - The basic device structure
657 * @parent: The device's "parent" device, the device to which it is attached.
658 * In most cases, a parent device is some sort of bus or host
659 * controller. If parent is NULL, the device, is a top-level device,
660 * which is not usually what you want.
661 * @p: Holds the private data of the driver core portions of the device.
662 * See the comment of the struct device_private for detail.
663 * @kobj: A top-level, abstract class from which other classes are derived.
664 * @init_name: Initial name of the device.
665 * @type: The type of device.
666 * This identifies the device type and carries type-specific
668 * @mutex: Mutex to synchronize calls to its driver.
669 * @bus: Type of bus device is on.
670 * @driver: Which driver has allocated this
671 * @platform_data: Platform data specific to the device.
672 * Example: For devices on custom boards, as typical of embedded
673 * and SOC based hardware, Linux often uses platform_data to point
674 * to board-specific structures describing devices and how they
675 * are wired. That can include what ports are available, chip
676 * variants, which GPIO pins act in what additional roles, and so
677 * on. This shrinks the "Board Support Packages" (BSPs) and
678 * minimizes board-specific #ifdefs in drivers.
679 * @power: For device power management.
680 * See Documentation/power/devices.txt for details.
681 * @pm_domain: Provide callbacks that are executed during system suspend,
682 * hibernation, system resume and during runtime PM transitions
683 * along with subsystem-level and driver-level callbacks.
684 * @pins: For device pin management.
685 * See Documentation/pinctrl.txt for details.
686 * @numa_node: NUMA node this device is close to.
687 * @dma_mask: Dma mask (if dma'ble device).
688 * @coherent_dma_mask: Like dma_mask, but for alloc_coherent mapping as not all
689 * hardware supports 64-bit addresses for consistent allocations
691 * @dma_parms: A low level driver may set these to teach IOMMU code about
692 * segment limitations.
693 * @dma_pools: Dma pools (if dma'ble device).
694 * @dma_mem: Internal for coherent mem override.
695 * @cma_area: Contiguous memory area for dma allocations
696 * @archdata: For arch-specific additions.
697 * @of_node: Associated device tree node.
698 * @acpi_node: Associated ACPI device node.
699 * @devt: For creating the sysfs "dev".
700 * @id: device instance
701 * @devres_lock: Spinlock to protect the resource of the device.
702 * @devres_head: The resources list of the device.
703 * @knode_class: The node used to add the device to the class list.
704 * @class: The class of the device.
705 * @groups: Optional attribute groups.
706 * @release: Callback to free the device after all references have
707 * gone away. This should be set by the allocator of the
708 * device (i.e. the bus driver that discovered the device).
709 * @iommu_group: IOMMU group the device belongs to.
711 * @offline_disabled: If set, the device is permanently online.
712 * @offline: Set after successful invocation of bus type's .offline().
714 * At the lowest level, every device in a Linux system is represented by an
715 * instance of struct device. The device structure contains the information
716 * that the device model core needs to model the system. Most subsystems,
717 * however, track additional information about the devices they host. As a
718 * result, it is rare for devices to be represented by bare device structures;
719 * instead, that structure, like kobject structures, is usually embedded within
720 * a higher-level representation of the device.
723 struct device *parent;
725 struct device_private *p;
728 const char *init_name; /* initial name of the device */
729 const struct device_type *type;
731 struct mutex mutex; /* mutex to synchronize calls to
735 struct bus_type *bus; /* type of bus device is on */
736 struct device_driver *driver; /* which driver has allocated this
738 void *platform_data; /* Platform specific data, device
739 core doesn't touch it */
740 struct dev_pm_info power;
741 struct dev_pm_domain *pm_domain;
743 #ifdef CONFIG_PINCTRL
744 struct dev_pin_info *pins;
748 int numa_node; /* NUMA node this device is close to */
750 u64 *dma_mask; /* dma mask (if dma'able device) */
751 u64 coherent_dma_mask;/* Like dma_mask, but for
752 alloc_coherent mappings as
753 not all hardware supports
754 64 bit addresses for consistent
755 allocations such descriptors. */
757 struct device_dma_parameters *dma_parms;
759 struct list_head dma_pools; /* dma pools (if dma'ble) */
761 struct dma_coherent_mem *dma_mem; /* internal for coherent mem
763 #ifdef CONFIG_DMA_CMA
764 struct cma *cma_area; /* contiguous memory area for dma
767 /* arch specific additions */
768 struct dev_archdata archdata;
770 struct device_node *of_node; /* associated device tree node */
771 struct acpi_dev_node acpi_node; /* associated ACPI device node */
773 dev_t devt; /* dev_t, creates the sysfs "dev" */
774 u32 id; /* device instance */
776 spinlock_t devres_lock;
777 struct list_head devres_head;
779 struct klist_node knode_class;
781 const struct attribute_group **groups; /* optional groups */
783 void (*release)(struct device *dev);
784 struct iommu_group *iommu_group;
786 bool offline_disabled:1;
790 static inline struct device *kobj_to_dev(struct kobject *kobj)
792 return container_of(kobj, struct device, kobj);
795 /* Get the wakeup routines, which depend on struct device */
796 #include <linux/pm_wakeup.h>
798 static inline const char *dev_name(const struct device *dev)
800 /* Use the init name until the kobject becomes available */
802 return dev->init_name;
804 return kobject_name(&dev->kobj);
807 extern __printf(2, 3)
808 int dev_set_name(struct device *dev, const char *name, ...);
811 static inline int dev_to_node(struct device *dev)
813 return dev->numa_node;
815 static inline void set_dev_node(struct device *dev, int node)
817 dev->numa_node = node;
820 static inline int dev_to_node(struct device *dev)
824 static inline void set_dev_node(struct device *dev, int node)
829 static inline struct pm_subsys_data *dev_to_psd(struct device *dev)
831 return dev ? dev->power.subsys_data : NULL;
834 static inline unsigned int dev_get_uevent_suppress(const struct device *dev)
836 return dev->kobj.uevent_suppress;
839 static inline void dev_set_uevent_suppress(struct device *dev, int val)
841 dev->kobj.uevent_suppress = val;
844 static inline int device_is_registered(struct device *dev)
846 return dev->kobj.state_in_sysfs;
849 static inline void device_enable_async_suspend(struct device *dev)
851 if (!dev->power.is_prepared)
852 dev->power.async_suspend = true;
855 static inline void device_disable_async_suspend(struct device *dev)
857 if (!dev->power.is_prepared)
858 dev->power.async_suspend = false;
861 static inline bool device_async_suspend_enabled(struct device *dev)
863 return !!dev->power.async_suspend;
866 static inline void pm_suspend_ignore_children(struct device *dev, bool enable)
868 dev->power.ignore_children = enable;
871 static inline void dev_pm_syscore_device(struct device *dev, bool val)
873 #ifdef CONFIG_PM_SLEEP
874 dev->power.syscore = val;
878 static inline void device_lock(struct device *dev)
880 mutex_lock(&dev->mutex);
883 static inline int device_trylock(struct device *dev)
885 return mutex_trylock(&dev->mutex);
888 static inline void device_unlock(struct device *dev)
890 mutex_unlock(&dev->mutex);
893 void driver_init(void);
896 * High level routines for use by the bus drivers
898 extern int __must_check device_register(struct device *dev);
899 extern void device_unregister(struct device *dev);
900 extern void device_initialize(struct device *dev);
901 extern int __must_check device_add(struct device *dev);
902 extern void device_del(struct device *dev);
903 extern int device_for_each_child(struct device *dev, void *data,
904 int (*fn)(struct device *dev, void *data));
905 extern struct device *device_find_child(struct device *dev, void *data,
906 int (*match)(struct device *dev, void *data));
907 extern int device_rename(struct device *dev, const char *new_name);
908 extern int device_move(struct device *dev, struct device *new_parent,
909 enum dpm_order dpm_order);
910 extern const char *device_get_devnode(struct device *dev,
911 umode_t *mode, kuid_t *uid, kgid_t *gid,
913 extern void *dev_get_drvdata(const struct device *dev);
914 extern int dev_set_drvdata(struct device *dev, void *data);
916 static inline bool device_supports_offline(struct device *dev)
918 return dev->bus && dev->bus->offline && dev->bus->online;
921 extern void lock_device_hotplug(void);
922 extern void unlock_device_hotplug(void);
923 extern int lock_device_hotplug_sysfs(void);
924 extern int device_offline(struct device *dev);
925 extern int device_online(struct device *dev);
927 * Root device objects for grouping under /sys/devices
929 extern struct device *__root_device_register(const char *name,
930 struct module *owner);
933 * This is a macro to avoid include problems with THIS_MODULE,
934 * just as per what is done for device_schedule_callback() above.
936 #define root_device_register(name) \
937 __root_device_register(name, THIS_MODULE)
939 extern void root_device_unregister(struct device *root);
941 static inline void *dev_get_platdata(const struct device *dev)
943 return dev->platform_data;
947 * Manual binding of a device to driver. See drivers/base/bus.c
948 * for information on use.
950 extern int __must_check device_bind_driver(struct device *dev);
951 extern void device_release_driver(struct device *dev);
952 extern int __must_check device_attach(struct device *dev);
953 extern int __must_check driver_attach(struct device_driver *drv);
954 extern int __must_check device_reprobe(struct device *dev);
957 * Easy functions for dynamically creating devices on the fly
959 extern struct device *device_create_vargs(struct class *cls,
960 struct device *parent,
965 extern __printf(5, 6)
966 struct device *device_create(struct class *cls, struct device *parent,
967 dev_t devt, void *drvdata,
968 const char *fmt, ...);
969 extern __printf(6, 7)
970 struct device *device_create_with_groups(struct class *cls,
971 struct device *parent, dev_t devt, void *drvdata,
972 const struct attribute_group **groups,
973 const char *fmt, ...);
974 extern void device_destroy(struct class *cls, dev_t devt);
977 * Platform "fixup" functions - allow the platform to have their say
978 * about devices and actions that the general device layer doesn't
981 /* Notify platform of device discovery */
982 extern int (*platform_notify)(struct device *dev);
984 extern int (*platform_notify_remove)(struct device *dev);
988 * get_device - atomically increment the reference count for the device.
991 extern struct device *get_device(struct device *dev);
992 extern void put_device(struct device *dev);
994 #ifdef CONFIG_DEVTMPFS
995 extern int devtmpfs_create_node(struct device *dev);
996 extern int devtmpfs_delete_node(struct device *dev);
997 extern int devtmpfs_mount(const char *mntdir);
999 static inline int devtmpfs_create_node(struct device *dev) { return 0; }
1000 static inline int devtmpfs_delete_node(struct device *dev) { return 0; }
1001 static inline int devtmpfs_mount(const char *mountpoint) { return 0; }
1004 /* drivers/base/power/shutdown.c */
1005 extern void device_shutdown(void);
1007 /* debugging and troubleshooting/diagnostic helpers. */
1008 extern const char *dev_driver_string(const struct device *dev);
1011 #ifdef CONFIG_PRINTK
1013 extern __printf(3, 0)
1014 int dev_vprintk_emit(int level, const struct device *dev,
1015 const char *fmt, va_list args);
1016 extern __printf(3, 4)
1017 int dev_printk_emit(int level, const struct device *dev, const char *fmt, ...);
1019 extern __printf(3, 4)
1020 int dev_printk(const char *level, const struct device *dev,
1021 const char *fmt, ...);
1022 extern __printf(2, 3)
1023 int dev_emerg(const struct device *dev, const char *fmt, ...);
1024 extern __printf(2, 3)
1025 int dev_alert(const struct device *dev, const char *fmt, ...);
1026 extern __printf(2, 3)
1027 int dev_crit(const struct device *dev, const char *fmt, ...);
1028 extern __printf(2, 3)
1029 int dev_err(const struct device *dev, const char *fmt, ...);
1030 extern __printf(2, 3)
1031 int dev_warn(const struct device *dev, const char *fmt, ...);
1032 extern __printf(2, 3)
1033 int dev_notice(const struct device *dev, const char *fmt, ...);
1034 extern __printf(2, 3)
1035 int _dev_info(const struct device *dev, const char *fmt, ...);
1039 static inline __printf(3, 0)
1040 int dev_vprintk_emit(int level, const struct device *dev,
1041 const char *fmt, va_list args)
1043 static inline __printf(3, 4)
1044 int dev_printk_emit(int level, const struct device *dev, const char *fmt, ...)
1047 static inline int __dev_printk(const char *level, const struct device *dev,
1048 struct va_format *vaf)
1050 static inline __printf(3, 4)
1051 int dev_printk(const char *level, const struct device *dev,
1052 const char *fmt, ...)
1055 static inline __printf(2, 3)
1056 int dev_emerg(const struct device *dev, const char *fmt, ...)
1058 static inline __printf(2, 3)
1059 int dev_crit(const struct device *dev, const char *fmt, ...)
1061 static inline __printf(2, 3)
1062 int dev_alert(const struct device *dev, const char *fmt, ...)
1064 static inline __printf(2, 3)
1065 int dev_err(const struct device *dev, const char *fmt, ...)
1067 static inline __printf(2, 3)
1068 int dev_warn(const struct device *dev, const char *fmt, ...)
1070 static inline __printf(2, 3)
1071 int dev_notice(const struct device *dev, const char *fmt, ...)
1073 static inline __printf(2, 3)
1074 int _dev_info(const struct device *dev, const char *fmt, ...)
1080 * Stupid hackaround for existing uses of non-printk uses dev_info
1082 * Note that the definition of dev_info below is actually _dev_info
1083 * and a macro is used to avoid redefining dev_info
1086 #define dev_info(dev, fmt, arg...) _dev_info(dev, fmt, ##arg)
1088 #if defined(CONFIG_DYNAMIC_DEBUG)
1089 #define dev_dbg(dev, format, ...) \
1091 dynamic_dev_dbg(dev, format, ##__VA_ARGS__); \
1093 #elif defined(DEBUG)
1094 #define dev_dbg(dev, format, arg...) \
1095 dev_printk(KERN_DEBUG, dev, format, ##arg)
1097 #define dev_dbg(dev, format, arg...) \
1100 dev_printk(KERN_DEBUG, dev, format, ##arg); \
1105 #define dev_level_ratelimited(dev_level, dev, fmt, ...) \
1107 static DEFINE_RATELIMIT_STATE(_rs, \
1108 DEFAULT_RATELIMIT_INTERVAL, \
1109 DEFAULT_RATELIMIT_BURST); \
1110 if (__ratelimit(&_rs)) \
1111 dev_level(dev, fmt, ##__VA_ARGS__); \
1114 #define dev_emerg_ratelimited(dev, fmt, ...) \
1115 dev_level_ratelimited(dev_emerg, dev, fmt, ##__VA_ARGS__)
1116 #define dev_alert_ratelimited(dev, fmt, ...) \
1117 dev_level_ratelimited(dev_alert, dev, fmt, ##__VA_ARGS__)
1118 #define dev_crit_ratelimited(dev, fmt, ...) \
1119 dev_level_ratelimited(dev_crit, dev, fmt, ##__VA_ARGS__)
1120 #define dev_err_ratelimited(dev, fmt, ...) \
1121 dev_level_ratelimited(dev_err, dev, fmt, ##__VA_ARGS__)
1122 #define dev_warn_ratelimited(dev, fmt, ...) \
1123 dev_level_ratelimited(dev_warn, dev, fmt, ##__VA_ARGS__)
1124 #define dev_notice_ratelimited(dev, fmt, ...) \
1125 dev_level_ratelimited(dev_notice, dev, fmt, ##__VA_ARGS__)
1126 #define dev_info_ratelimited(dev, fmt, ...) \
1127 dev_level_ratelimited(dev_info, dev, fmt, ##__VA_ARGS__)
1128 #if defined(CONFIG_DYNAMIC_DEBUG)
1129 /* descriptor check is first to prevent flooding with "callbacks suppressed" */
1130 #define dev_dbg_ratelimited(dev, fmt, ...) \
1132 static DEFINE_RATELIMIT_STATE(_rs, \
1133 DEFAULT_RATELIMIT_INTERVAL, \
1134 DEFAULT_RATELIMIT_BURST); \
1135 DEFINE_DYNAMIC_DEBUG_METADATA(descriptor, fmt); \
1136 if (unlikely(descriptor.flags & _DPRINTK_FLAGS_PRINT) && \
1137 __ratelimit(&_rs)) \
1138 __dynamic_dev_dbg(&descriptor, dev, fmt, \
1141 #elif defined(DEBUG)
1142 #define dev_dbg_ratelimited(dev, fmt, ...) \
1144 static DEFINE_RATELIMIT_STATE(_rs, \
1145 DEFAULT_RATELIMIT_INTERVAL, \
1146 DEFAULT_RATELIMIT_BURST); \
1147 if (__ratelimit(&_rs)) \
1148 dev_printk(KERN_DEBUG, dev, fmt, ##__VA_ARGS__); \
1151 #define dev_dbg_ratelimited(dev, fmt, ...) \
1152 no_printk(KERN_DEBUG pr_fmt(fmt), ##__VA_ARGS__)
1155 #ifdef VERBOSE_DEBUG
1156 #define dev_vdbg dev_dbg
1158 #define dev_vdbg(dev, format, arg...) \
1161 dev_printk(KERN_DEBUG, dev, format, ##arg); \
1167 * dev_WARN*() acts like dev_printk(), but with the key difference of
1168 * using WARN/WARN_ONCE to include file/line information and a backtrace.
1170 #define dev_WARN(dev, format, arg...) \
1171 WARN(1, "%s %s: " format, dev_driver_string(dev), dev_name(dev), ## arg);
1173 #define dev_WARN_ONCE(dev, condition, format, arg...) \
1174 WARN_ONCE(condition, "%s %s: " format, \
1175 dev_driver_string(dev), dev_name(dev), ## arg)
1177 /* Create alias, so I can be autoloaded. */
1178 #define MODULE_ALIAS_CHARDEV(major,minor) \
1179 MODULE_ALIAS("char-major-" __stringify(major) "-" __stringify(minor))
1180 #define MODULE_ALIAS_CHARDEV_MAJOR(major) \
1181 MODULE_ALIAS("char-major-" __stringify(major) "-*")
1183 #ifdef CONFIG_SYSFS_DEPRECATED
1184 extern long sysfs_deprecated;
1186 #define sysfs_deprecated 0
1190 * module_driver() - Helper macro for drivers that don't do anything
1191 * special in module init/exit. This eliminates a lot of boilerplate.
1192 * Each module may only use this macro once, and calling it replaces
1193 * module_init() and module_exit().
1195 * @__driver: driver name
1196 * @__register: register function for this driver type
1197 * @__unregister: unregister function for this driver type
1198 * @...: Additional arguments to be passed to __register and __unregister.
1200 * Use this macro to construct bus specific macros for registering
1201 * drivers, and do not use it on its own.
1203 #define module_driver(__driver, __register, __unregister, ...) \
1204 static int __init __driver##_init(void) \
1206 return __register(&(__driver) , ##__VA_ARGS__); \
1208 module_init(__driver##_init); \
1209 static void __exit __driver##_exit(void) \
1211 __unregister(&(__driver) , ##__VA_ARGS__); \
1213 module_exit(__driver##_exit);
1215 #endif /* _DEVICE_H_ */