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)
53 extern int __must_check bus_create_file(struct bus_type *,
54 struct bus_attribute *);
55 extern void bus_remove_file(struct bus_type *, struct bus_attribute *);
58 * struct bus_type - The bus type of the device
60 * @name: The name of the bus.
61 * @dev_name: Used for subsystems to enumerate devices like ("foo%u", dev->id).
62 * @dev_root: Default device to use as the parent.
63 * @bus_attrs: Default attributes of the bus.
64 * @dev_attrs: Default attributes of the devices on the bus.
65 * @drv_attrs: Default attributes of the device drivers on the bus.
66 * @match: Called, perhaps multiple times, whenever a new device or driver
67 * is added for this bus. It should return a nonzero value if the
68 * given device can be handled by the given driver.
69 * @uevent: Called when a device is added, removed, or a few other things
70 * that generate uevents to add the environment variables.
71 * @probe: Called when a new device or driver add to this bus, and callback
72 * the specific driver's probe to initial the matched device.
73 * @remove: Called when a device removed from this bus.
74 * @shutdown: Called at shut-down time to quiesce the device.
75 * @suspend: Called when a device on this bus wants to go to sleep mode.
76 * @resume: Called to bring a device on this bus out of sleep mode.
77 * @pm: Power management operations of this bus, callback the specific
78 * device driver's pm-ops.
79 * @iommu_ops: IOMMU specific operations for this bus, used to attach IOMMU
80 * driver implementations to a bus and allow the driver to do
82 * @p: The private data of the driver core, only the driver core can
85 * A bus is a channel between the processor and one or more devices. For the
86 * purposes of the device model, all devices are connected via a bus, even if
87 * it is an internal, virtual, "platform" bus. Buses can plug into each other.
88 * A USB controller is usually a PCI device, for example. The device model
89 * represents the actual connections between buses and the devices they control.
90 * A bus is represented by the bus_type structure. It contains the name, the
91 * default attributes, the bus' methods, PM operations, and the driver core's
97 struct device *dev_root;
98 struct bus_attribute *bus_attrs;
99 struct device_attribute *dev_attrs;
100 struct driver_attribute *drv_attrs;
102 int (*match)(struct device *dev, struct device_driver *drv);
103 int (*uevent)(struct device *dev, struct kobj_uevent_env *env);
104 int (*probe)(struct device *dev);
105 int (*remove)(struct device *dev);
106 void (*shutdown)(struct device *dev);
108 int (*suspend)(struct device *dev, pm_message_t state);
109 int (*resume)(struct device *dev);
111 const struct dev_pm_ops *pm;
113 struct iommu_ops *iommu_ops;
115 struct subsys_private *p;
116 struct lock_class_key lock_key;
119 extern int __must_check bus_register(struct bus_type *bus);
121 extern void bus_unregister(struct bus_type *bus);
123 extern int __must_check bus_rescan_devices(struct bus_type *bus);
125 /* iterator helpers for buses */
126 struct subsys_dev_iter {
127 struct klist_iter ki;
128 const struct device_type *type;
130 void subsys_dev_iter_init(struct subsys_dev_iter *iter,
131 struct bus_type *subsys,
132 struct device *start,
133 const struct device_type *type);
134 struct device *subsys_dev_iter_next(struct subsys_dev_iter *iter);
135 void subsys_dev_iter_exit(struct subsys_dev_iter *iter);
137 int bus_for_each_dev(struct bus_type *bus, struct device *start, void *data,
138 int (*fn)(struct device *dev, void *data));
139 struct device *bus_find_device(struct bus_type *bus, struct device *start,
141 int (*match)(struct device *dev, void *data));
142 struct device *bus_find_device_by_name(struct bus_type *bus,
143 struct device *start,
145 struct device *subsys_find_device_by_id(struct bus_type *bus, unsigned int id,
146 struct device *hint);
147 int bus_for_each_drv(struct bus_type *bus, struct device_driver *start,
148 void *data, int (*fn)(struct device_driver *, void *));
149 void bus_sort_breadthfirst(struct bus_type *bus,
150 int (*compare)(const struct device *a,
151 const struct device *b));
153 * Bus notifiers: Get notified of addition/removal of devices
154 * and binding/unbinding of drivers to devices.
155 * In the long run, it should be a replacement for the platform
158 struct notifier_block;
160 extern int bus_register_notifier(struct bus_type *bus,
161 struct notifier_block *nb);
162 extern int bus_unregister_notifier(struct bus_type *bus,
163 struct notifier_block *nb);
165 /* All 4 notifers below get called with the target struct device *
166 * as an argument. Note that those functions are likely to be called
167 * with the device lock held in the core, so be careful.
169 #define BUS_NOTIFY_ADD_DEVICE 0x00000001 /* device added */
170 #define BUS_NOTIFY_DEL_DEVICE 0x00000002 /* device removed */
171 #define BUS_NOTIFY_BIND_DRIVER 0x00000003 /* driver about to be
173 #define BUS_NOTIFY_BOUND_DRIVER 0x00000004 /* driver bound to device */
174 #define BUS_NOTIFY_UNBIND_DRIVER 0x00000005 /* driver about to be
176 #define BUS_NOTIFY_UNBOUND_DRIVER 0x00000006 /* driver is unbound
179 extern struct kset *bus_get_kset(struct bus_type *bus);
180 extern struct klist *bus_get_device_klist(struct bus_type *bus);
183 * struct device_driver - The basic device driver structure
184 * @name: Name of the device driver.
185 * @bus: The bus which the device of this driver belongs to.
186 * @owner: The module owner.
187 * @mod_name: Used for built-in modules.
188 * @suppress_bind_attrs: Disables bind/unbind via sysfs.
189 * @of_match_table: The open firmware table.
190 * @acpi_match_table: The ACPI match table.
191 * @probe: Called to query the existence of a specific device,
192 * whether this driver can work with it, and bind the driver
193 * to a specific device.
194 * @remove: Called when the device is removed from the system to
195 * unbind a device from this driver.
196 * @shutdown: Called at shut-down time to quiesce the device.
197 * @suspend: Called to put the device to sleep mode. Usually to a
199 * @resume: Called to bring a device from sleep mode.
200 * @groups: Default attributes that get created by the driver core
202 * @pm: Power management operations of the device which matched
204 * @p: Driver core's private data, no one other than the driver
205 * core can touch this.
207 * The device driver-model tracks all of the drivers known to the system.
208 * The main reason for this tracking is to enable the driver core to match
209 * up drivers with new devices. Once drivers are known objects within the
210 * system, however, a number of other things become possible. Device drivers
211 * can export information and configuration variables that are independent
212 * of any specific device.
214 struct device_driver {
216 struct bus_type *bus;
218 struct module *owner;
219 const char *mod_name; /* used for built-in modules */
221 bool suppress_bind_attrs; /* disables bind/unbind via sysfs */
223 const struct of_device_id *of_match_table;
224 const struct acpi_device_id *acpi_match_table;
226 int (*probe) (struct device *dev);
227 int (*remove) (struct device *dev);
228 void (*shutdown) (struct device *dev);
229 int (*suspend) (struct device *dev, pm_message_t state);
230 int (*resume) (struct device *dev);
231 const struct attribute_group **groups;
233 const struct dev_pm_ops *pm;
235 struct driver_private *p;
239 extern int __must_check driver_register(struct device_driver *drv);
240 extern void driver_unregister(struct device_driver *drv);
242 extern struct device_driver *driver_find(const char *name,
243 struct bus_type *bus);
244 extern int driver_probe_done(void);
245 extern void wait_for_device_probe(void);
248 /* sysfs interface for exporting driver attributes */
250 struct driver_attribute {
251 struct attribute attr;
252 ssize_t (*show)(struct device_driver *driver, char *buf);
253 ssize_t (*store)(struct device_driver *driver, const char *buf,
257 #define DRIVER_ATTR(_name, _mode, _show, _store) \
258 struct driver_attribute driver_attr_##_name = \
259 __ATTR(_name, _mode, _show, _store)
261 extern int __must_check driver_create_file(struct device_driver *driver,
262 const struct driver_attribute *attr);
263 extern void driver_remove_file(struct device_driver *driver,
264 const struct driver_attribute *attr);
266 extern int __must_check driver_for_each_device(struct device_driver *drv,
267 struct device *start,
269 int (*fn)(struct device *dev,
271 struct device *driver_find_device(struct device_driver *drv,
272 struct device *start, void *data,
273 int (*match)(struct device *dev, void *data));
276 * struct subsys_interface - interfaces to device functions
277 * @name: name of the device function
278 * @subsys: subsytem of the devices to attach to
279 * @node: the list of functions registered at the subsystem
280 * @add_dev: device hookup to device function handler
281 * @remove_dev: device hookup to device function handler
283 * Simple interfaces attached to a subsystem. Multiple interfaces can
284 * attach to a subsystem and its devices. Unlike drivers, they do not
285 * exclusively claim or control devices. Interfaces usually represent
286 * a specific functionality of a subsystem/class of devices.
288 struct subsys_interface {
290 struct bus_type *subsys;
291 struct list_head node;
292 int (*add_dev)(struct device *dev, struct subsys_interface *sif);
293 int (*remove_dev)(struct device *dev, struct subsys_interface *sif);
296 int subsys_interface_register(struct subsys_interface *sif);
297 void subsys_interface_unregister(struct subsys_interface *sif);
299 int subsys_system_register(struct bus_type *subsys,
300 const struct attribute_group **groups);
301 int subsys_virtual_register(struct bus_type *subsys,
302 const struct attribute_group **groups);
305 * struct class - device classes
306 * @name: Name of the class.
307 * @owner: The module owner.
308 * @class_attrs: Default attributes of this class.
309 * @dev_attrs: Default attributes of the devices belong to the class.
310 * @dev_bin_attrs: Default binary attributes of the devices belong to the class.
311 * @dev_kobj: The kobject that represents this class and links it into the hierarchy.
312 * @dev_uevent: Called when a device is added, removed from this class, or a
313 * few other things that generate uevents to add the environment
315 * @devnode: Callback to provide the devtmpfs.
316 * @class_release: Called to release this class.
317 * @dev_release: Called to release the device.
318 * @suspend: Used to put the device to sleep mode, usually to a low power
320 * @resume: Used to bring the device from the sleep mode.
321 * @ns_type: Callbacks so sysfs can detemine namespaces.
322 * @namespace: Namespace of the device belongs to this class.
323 * @pm: The default device power management operations of this class.
324 * @p: The private data of the driver core, no one other than the
325 * driver core can touch this.
327 * A class is a higher-level view of a device that abstracts out low-level
328 * implementation details. Drivers may see a SCSI disk or an ATA disk, but,
329 * at the class level, they are all simply disks. Classes allow user space
330 * to work with devices based on what they do, rather than how they are
331 * connected or how they work.
335 struct module *owner;
337 struct class_attribute *class_attrs;
338 struct device_attribute *dev_attrs;
339 struct bin_attribute *dev_bin_attrs;
340 struct kobject *dev_kobj;
342 int (*dev_uevent)(struct device *dev, struct kobj_uevent_env *env);
343 char *(*devnode)(struct device *dev, umode_t *mode);
345 void (*class_release)(struct class *class);
346 void (*dev_release)(struct device *dev);
348 int (*suspend)(struct device *dev, pm_message_t state);
349 int (*resume)(struct device *dev);
351 const struct kobj_ns_type_operations *ns_type;
352 const void *(*namespace)(struct device *dev);
354 const struct dev_pm_ops *pm;
356 struct subsys_private *p;
359 struct class_dev_iter {
360 struct klist_iter ki;
361 const struct device_type *type;
364 extern struct kobject *sysfs_dev_block_kobj;
365 extern struct kobject *sysfs_dev_char_kobj;
366 extern int __must_check __class_register(struct class *class,
367 struct lock_class_key *key);
368 extern void class_unregister(struct class *class);
370 /* This is a #define to keep the compiler from merging different
371 * instances of the __key variable */
372 #define class_register(class) \
374 static struct lock_class_key __key; \
375 __class_register(class, &__key); \
379 struct class_compat *class_compat_register(const char *name);
380 void class_compat_unregister(struct class_compat *cls);
381 int class_compat_create_link(struct class_compat *cls, struct device *dev,
382 struct device *device_link);
383 void class_compat_remove_link(struct class_compat *cls, struct device *dev,
384 struct device *device_link);
386 extern void class_dev_iter_init(struct class_dev_iter *iter,
388 struct device *start,
389 const struct device_type *type);
390 extern struct device *class_dev_iter_next(struct class_dev_iter *iter);
391 extern void class_dev_iter_exit(struct class_dev_iter *iter);
393 extern int class_for_each_device(struct class *class, struct device *start,
395 int (*fn)(struct device *dev, void *data));
396 extern struct device *class_find_device(struct class *class,
397 struct device *start, const void *data,
398 int (*match)(struct device *, const void *));
400 struct class_attribute {
401 struct attribute attr;
402 ssize_t (*show)(struct class *class, struct class_attribute *attr,
404 ssize_t (*store)(struct class *class, struct class_attribute *attr,
405 const char *buf, size_t count);
406 const void *(*namespace)(struct class *class,
407 const struct class_attribute *attr);
410 #define CLASS_ATTR(_name, _mode, _show, _store) \
411 struct class_attribute class_attr_##_name = __ATTR(_name, _mode, _show, _store)
413 extern int __must_check class_create_file(struct class *class,
414 const struct class_attribute *attr);
415 extern void class_remove_file(struct class *class,
416 const struct class_attribute *attr);
418 /* Simple class attribute that is just a static string */
420 struct class_attribute_string {
421 struct class_attribute attr;
425 /* Currently read-only only */
426 #define _CLASS_ATTR_STRING(_name, _mode, _str) \
427 { __ATTR(_name, _mode, show_class_attr_string, NULL), _str }
428 #define CLASS_ATTR_STRING(_name, _mode, _str) \
429 struct class_attribute_string class_attr_##_name = \
430 _CLASS_ATTR_STRING(_name, _mode, _str)
432 extern ssize_t show_class_attr_string(struct class *class, struct class_attribute *attr,
435 struct class_interface {
436 struct list_head node;
439 int (*add_dev) (struct device *, struct class_interface *);
440 void (*remove_dev) (struct device *, struct class_interface *);
443 extern int __must_check class_interface_register(struct class_interface *);
444 extern void class_interface_unregister(struct class_interface *);
446 extern struct class * __must_check __class_create(struct module *owner,
448 struct lock_class_key *key);
449 extern void class_destroy(struct class *cls);
451 /* This is a #define to keep the compiler from merging different
452 * instances of the __key variable */
453 #define class_create(owner, name) \
455 static struct lock_class_key __key; \
456 __class_create(owner, name, &__key); \
460 * The type of device, "struct device" is embedded in. A class
461 * or bus can contain devices of different types
462 * like "partitions" and "disks", "mouse" and "event".
463 * This identifies the device type and carries type-specific
464 * information, equivalent to the kobj_type of a kobject.
465 * If "name" is specified, the uevent will contain it in
466 * the DEVTYPE variable.
470 const struct attribute_group **groups;
471 int (*uevent)(struct device *dev, struct kobj_uevent_env *env);
472 char *(*devnode)(struct device *dev, umode_t *mode,
473 kuid_t *uid, kgid_t *gid);
474 void (*release)(struct device *dev);
476 const struct dev_pm_ops *pm;
479 /* interface for exporting device attributes */
480 struct device_attribute {
481 struct attribute attr;
482 ssize_t (*show)(struct device *dev, struct device_attribute *attr,
484 ssize_t (*store)(struct device *dev, struct device_attribute *attr,
485 const char *buf, size_t count);
488 struct dev_ext_attribute {
489 struct device_attribute attr;
493 ssize_t device_show_ulong(struct device *dev, struct device_attribute *attr,
495 ssize_t device_store_ulong(struct device *dev, struct device_attribute *attr,
496 const char *buf, size_t count);
497 ssize_t device_show_int(struct device *dev, struct device_attribute *attr,
499 ssize_t device_store_int(struct device *dev, struct device_attribute *attr,
500 const char *buf, size_t count);
501 ssize_t device_show_bool(struct device *dev, struct device_attribute *attr,
503 ssize_t device_store_bool(struct device *dev, struct device_attribute *attr,
504 const char *buf, size_t count);
506 #define DEVICE_ATTR(_name, _mode, _show, _store) \
507 struct device_attribute dev_attr_##_name = __ATTR(_name, _mode, _show, _store)
508 #define DEVICE_ULONG_ATTR(_name, _mode, _var) \
509 struct dev_ext_attribute dev_attr_##_name = \
510 { __ATTR(_name, _mode, device_show_ulong, device_store_ulong), &(_var) }
511 #define DEVICE_INT_ATTR(_name, _mode, _var) \
512 struct dev_ext_attribute dev_attr_##_name = \
513 { __ATTR(_name, _mode, device_show_int, device_store_int), &(_var) }
514 #define DEVICE_BOOL_ATTR(_name, _mode, _var) \
515 struct dev_ext_attribute dev_attr_##_name = \
516 { __ATTR(_name, _mode, device_show_bool, device_store_bool), &(_var) }
517 #define DEVICE_ATTR_IGNORE_LOCKDEP(_name, _mode, _show, _store) \
518 struct device_attribute dev_attr_##_name = \
519 __ATTR_IGNORE_LOCKDEP(_name, _mode, _show, _store)
521 extern int device_create_file(struct device *device,
522 const struct device_attribute *entry);
523 extern void device_remove_file(struct device *dev,
524 const struct device_attribute *attr);
525 extern int __must_check device_create_bin_file(struct device *dev,
526 const struct bin_attribute *attr);
527 extern void device_remove_bin_file(struct device *dev,
528 const struct bin_attribute *attr);
529 extern int device_schedule_callback_owner(struct device *dev,
530 void (*func)(struct device *dev), struct module *owner);
532 /* This is a macro to avoid include problems with THIS_MODULE */
533 #define device_schedule_callback(dev, func) \
534 device_schedule_callback_owner(dev, func, THIS_MODULE)
536 /* device resource management */
537 typedef void (*dr_release_t)(struct device *dev, void *res);
538 typedef int (*dr_match_t)(struct device *dev, void *res, void *match_data);
540 #ifdef CONFIG_DEBUG_DEVRES
541 extern void *__devres_alloc(dr_release_t release, size_t size, gfp_t gfp,
543 #define devres_alloc(release, size, gfp) \
544 __devres_alloc(release, size, gfp, #release)
546 extern void *devres_alloc(dr_release_t release, size_t size, gfp_t gfp);
548 extern void devres_for_each_res(struct device *dev, dr_release_t release,
549 dr_match_t match, void *match_data,
550 void (*fn)(struct device *, void *, void *),
552 extern void devres_free(void *res);
553 extern void devres_add(struct device *dev, void *res);
554 extern void *devres_find(struct device *dev, dr_release_t release,
555 dr_match_t match, void *match_data);
556 extern void *devres_get(struct device *dev, void *new_res,
557 dr_match_t match, void *match_data);
558 extern void *devres_remove(struct device *dev, dr_release_t release,
559 dr_match_t match, void *match_data);
560 extern int devres_destroy(struct device *dev, dr_release_t release,
561 dr_match_t match, void *match_data);
562 extern int devres_release(struct device *dev, dr_release_t release,
563 dr_match_t match, void *match_data);
566 extern void * __must_check devres_open_group(struct device *dev, void *id,
568 extern void devres_close_group(struct device *dev, void *id);
569 extern void devres_remove_group(struct device *dev, void *id);
570 extern int devres_release_group(struct device *dev, void *id);
572 /* managed devm_k.alloc/kfree for device drivers */
573 extern void *devm_kmalloc(struct device *dev, size_t size, gfp_t gfp);
574 static inline void *devm_kzalloc(struct device *dev, size_t size, gfp_t gfp)
576 return devm_kmalloc(dev, size, gfp | __GFP_ZERO);
578 static inline void *devm_kmalloc_array(struct device *dev,
579 size_t n, size_t size, gfp_t flags)
581 if (size != 0 && n > SIZE_MAX / size)
583 return devm_kmalloc(dev, n * size, flags);
585 static inline void *devm_kcalloc(struct device *dev,
586 size_t n, size_t size, gfp_t flags)
588 return devm_kmalloc_array(dev, n, size, flags | __GFP_ZERO);
590 extern void devm_kfree(struct device *dev, void *p);
592 void __iomem *devm_ioremap_resource(struct device *dev, struct resource *res);
593 void __iomem *devm_request_and_ioremap(struct device *dev,
594 struct resource *res);
596 void __iomem *devm_ioremap_exec_resource(struct device *dev,
597 struct resource *res);
598 void __iomem *devm_request_and_ioremap_exec(struct device *dev,
599 struct resource *res);
601 /* allows to add/remove a custom action to devres stack */
602 int devm_add_action(struct device *dev, void (*action)(void *), void *data);
603 void devm_remove_action(struct device *dev, void (*action)(void *), void *data);
605 struct device_dma_parameters {
607 * a low level driver may set these to teach IOMMU code about
610 unsigned int max_segment_size;
611 unsigned long segment_boundary_mask;
614 struct acpi_dev_node {
621 * struct device - The basic device structure
622 * @parent: The device's "parent" device, the device to which it is attached.
623 * In most cases, a parent device is some sort of bus or host
624 * controller. If parent is NULL, the device, is a top-level device,
625 * which is not usually what you want.
626 * @p: Holds the private data of the driver core portions of the device.
627 * See the comment of the struct device_private for detail.
628 * @kobj: A top-level, abstract class from which other classes are derived.
629 * @init_name: Initial name of the device.
630 * @type: The type of device.
631 * This identifies the device type and carries type-specific
633 * @mutex: Mutex to synchronize calls to its driver.
634 * @bus: Type of bus device is on.
635 * @driver: Which driver has allocated this
636 * @platform_data: Platform data specific to the device.
637 * Example: For devices on custom boards, as typical of embedded
638 * and SOC based hardware, Linux often uses platform_data to point
639 * to board-specific structures describing devices and how they
640 * are wired. That can include what ports are available, chip
641 * variants, which GPIO pins act in what additional roles, and so
642 * on. This shrinks the "Board Support Packages" (BSPs) and
643 * minimizes board-specific #ifdefs in drivers.
644 * @power: For device power management.
645 * See Documentation/power/devices.txt for details.
646 * @pm_domain: Provide callbacks that are executed during system suspend,
647 * hibernation, system resume and during runtime PM transitions
648 * along with subsystem-level and driver-level callbacks.
649 * @pins: For device pin management.
650 * See Documentation/pinctrl.txt for details.
651 * @numa_node: NUMA node this device is close to.
652 * @dma_mask: Dma mask (if dma'ble device).
653 * @coherent_dma_mask: Like dma_mask, but for alloc_coherent mapping as not all
654 * hardware supports 64-bit addresses for consistent allocations
656 * @dma_parms: A low level driver may set these to teach IOMMU code about
657 * segment limitations.
658 * @dma_pools: Dma pools (if dma'ble device).
659 * @dma_mem: Internal for coherent mem override.
660 * @archdata: For arch-specific additions.
661 * @of_node: Associated device tree node.
662 * @acpi_node: Associated ACPI device node.
663 * @devt: For creating the sysfs "dev".
664 * @id: device instance
665 * @devres_lock: Spinlock to protect the resource of the device.
666 * @devres_head: The resources list of the device.
667 * @knode_class: The node used to add the device to the class list.
668 * @class: The class of the device.
669 * @groups: Optional attribute groups.
670 * @release: Callback to free the device after all references have
671 * gone away. This should be set by the allocator of the
672 * device (i.e. the bus driver that discovered the device).
674 * At the lowest level, every device in a Linux system is represented by an
675 * instance of struct device. The device structure contains the information
676 * that the device model core needs to model the system. Most subsystems,
677 * however, track additional information about the devices they host. As a
678 * result, it is rare for devices to be represented by bare device structures;
679 * instead, that structure, like kobject structures, is usually embedded within
680 * a higher-level representation of the device.
683 struct device *parent;
685 struct device_private *p;
688 const char *init_name; /* initial name of the device */
689 const struct device_type *type;
691 struct mutex mutex; /* mutex to synchronize calls to
695 struct bus_type *bus; /* type of bus device is on */
696 struct device_driver *driver; /* which driver has allocated this
698 void *platform_data; /* Platform specific data, device
699 core doesn't touch it */
700 struct dev_pm_info power;
701 struct dev_pm_domain *pm_domain;
703 #ifdef CONFIG_PINCTRL
704 struct dev_pin_info *pins;
708 int numa_node; /* NUMA node this device is close to */
710 u64 *dma_mask; /* dma mask (if dma'able device) */
711 u64 coherent_dma_mask;/* Like dma_mask, but for
712 alloc_coherent mappings as
713 not all hardware supports
714 64 bit addresses for consistent
715 allocations such descriptors. */
717 struct device_dma_parameters *dma_parms;
719 struct list_head dma_pools; /* dma pools (if dma'ble) */
721 struct dma_coherent_mem *dma_mem; /* internal for coherent mem
723 #ifdef CONFIG_DMA_CMA
724 struct cma *cma_area; /* contiguous memory area for dma
727 /* arch specific additions */
728 struct dev_archdata archdata;
730 struct device_node *of_node; /* associated device tree node */
731 struct acpi_dev_node acpi_node; /* associated ACPI device node */
733 dev_t devt; /* dev_t, creates the sysfs "dev" */
734 u32 id; /* device instance */
736 spinlock_t devres_lock;
737 struct list_head devres_head;
739 struct klist_node knode_class;
741 const struct attribute_group **groups; /* optional groups */
743 void (*release)(struct device *dev);
744 struct iommu_group *iommu_group;
747 static inline struct device *kobj_to_dev(struct kobject *kobj)
749 return container_of(kobj, struct device, kobj);
753 #define ACPI_HANDLE(dev) ((dev)->acpi_node.handle)
754 #define ACPI_HANDLE_SET(dev, _handle_) (dev)->acpi_node.handle = (_handle_)
756 #define ACPI_HANDLE(dev) (NULL)
757 #define ACPI_HANDLE_SET(dev, _handle_) do { } while (0)
760 /* Get the wakeup routines, which depend on struct device */
761 #include <linux/pm_wakeup.h>
763 static inline const char *dev_name(const struct device *dev)
765 /* Use the init name until the kobject becomes available */
767 return dev->init_name;
769 return kobject_name(&dev->kobj);
772 extern __printf(2, 3)
773 int dev_set_name(struct device *dev, const char *name, ...);
776 static inline int dev_to_node(struct device *dev)
778 return dev->numa_node;
780 static inline void set_dev_node(struct device *dev, int node)
782 dev->numa_node = node;
785 static inline int dev_to_node(struct device *dev)
789 static inline void set_dev_node(struct device *dev, int node)
794 static inline struct pm_subsys_data *dev_to_psd(struct device *dev)
796 return dev ? dev->power.subsys_data : NULL;
799 static inline unsigned int dev_get_uevent_suppress(const struct device *dev)
801 return dev->kobj.uevent_suppress;
804 static inline void dev_set_uevent_suppress(struct device *dev, int val)
806 dev->kobj.uevent_suppress = val;
809 static inline int device_is_registered(struct device *dev)
811 return dev->kobj.state_in_sysfs;
814 static inline void device_enable_async_suspend(struct device *dev)
816 if (!dev->power.is_prepared)
817 dev->power.async_suspend = true;
820 static inline void device_disable_async_suspend(struct device *dev)
822 if (!dev->power.is_prepared)
823 dev->power.async_suspend = false;
826 static inline bool device_async_suspend_enabled(struct device *dev)
828 return !!dev->power.async_suspend;
831 static inline void pm_suspend_ignore_children(struct device *dev, bool enable)
833 dev->power.ignore_children = enable;
836 static inline void dev_pm_syscore_device(struct device *dev, bool val)
838 #ifdef CONFIG_PM_SLEEP
839 dev->power.syscore = val;
843 static inline void device_lock(struct device *dev)
845 mutex_lock(&dev->mutex);
848 static inline int device_trylock(struct device *dev)
850 return mutex_trylock(&dev->mutex);
853 static inline void device_unlock(struct device *dev)
855 mutex_unlock(&dev->mutex);
858 void driver_init(void);
861 * High level routines for use by the bus drivers
863 extern int __must_check device_register(struct device *dev);
864 extern void device_unregister(struct device *dev);
865 extern void device_initialize(struct device *dev);
866 extern int __must_check device_add(struct device *dev);
867 extern void device_del(struct device *dev);
868 extern int device_for_each_child(struct device *dev, void *data,
869 int (*fn)(struct device *dev, void *data));
870 extern struct device *device_find_child(struct device *dev, void *data,
871 int (*match)(struct device *dev, void *data));
872 extern int device_rename(struct device *dev, const char *new_name);
873 extern int device_move(struct device *dev, struct device *new_parent,
874 enum dpm_order dpm_order);
875 extern const char *device_get_devnode(struct device *dev,
876 umode_t *mode, kuid_t *uid, kgid_t *gid,
878 extern void *dev_get_drvdata(const struct device *dev);
879 extern int dev_set_drvdata(struct device *dev, void *data);
882 * Root device objects for grouping under /sys/devices
884 extern struct device *__root_device_register(const char *name,
885 struct module *owner);
888 * This is a macro to avoid include problems with THIS_MODULE,
889 * just as per what is done for device_schedule_callback() above.
891 #define root_device_register(name) \
892 __root_device_register(name, THIS_MODULE)
894 extern void root_device_unregister(struct device *root);
896 static inline void *dev_get_platdata(const struct device *dev)
898 return dev->platform_data;
902 * Manual binding of a device to driver. See drivers/base/bus.c
903 * for information on use.
905 extern int __must_check device_bind_driver(struct device *dev);
906 extern void device_release_driver(struct device *dev);
907 extern int __must_check device_attach(struct device *dev);
908 extern int __must_check driver_attach(struct device_driver *drv);
909 extern int __must_check device_reprobe(struct device *dev);
912 * Easy functions for dynamically creating devices on the fly
914 extern struct device *device_create_vargs(struct class *cls,
915 struct device *parent,
920 extern __printf(5, 6)
921 struct device *device_create(struct class *cls, struct device *parent,
922 dev_t devt, void *drvdata,
923 const char *fmt, ...);
924 extern void device_destroy(struct class *cls, dev_t devt);
927 * Platform "fixup" functions - allow the platform to have their say
928 * about devices and actions that the general device layer doesn't
931 /* Notify platform of device discovery */
932 extern int (*platform_notify)(struct device *dev);
934 extern int (*platform_notify_remove)(struct device *dev);
938 * get_device - atomically increment the reference count for the device.
941 extern struct device *get_device(struct device *dev);
942 extern void put_device(struct device *dev);
944 #ifdef CONFIG_DEVTMPFS
945 extern int devtmpfs_create_node(struct device *dev);
946 extern int devtmpfs_delete_node(struct device *dev);
947 extern int devtmpfs_mount(const char *mntdir);
949 static inline int devtmpfs_create_node(struct device *dev) { return 0; }
950 static inline int devtmpfs_delete_node(struct device *dev) { return 0; }
951 static inline int devtmpfs_mount(const char *mountpoint) { return 0; }
954 /* drivers/base/power/shutdown.c */
955 extern void device_shutdown(void);
957 /* debugging and troubleshooting/diagnostic helpers. */
958 extern const char *dev_driver_string(const struct device *dev);
963 extern __printf(3, 0)
964 int dev_vprintk_emit(int level, const struct device *dev,
965 const char *fmt, va_list args);
966 extern __printf(3, 4)
967 int dev_printk_emit(int level, const struct device *dev, const char *fmt, ...);
969 extern __printf(3, 4)
970 int dev_printk(const char *level, const struct device *dev,
971 const char *fmt, ...);
972 extern __printf(2, 3)
973 int dev_emerg(const struct device *dev, const char *fmt, ...);
974 extern __printf(2, 3)
975 int dev_alert(const struct device *dev, const char *fmt, ...);
976 extern __printf(2, 3)
977 int dev_crit(const struct device *dev, const char *fmt, ...);
978 extern __printf(2, 3)
979 int dev_err(const struct device *dev, const char *fmt, ...);
980 extern __printf(2, 3)
981 int dev_warn(const struct device *dev, const char *fmt, ...);
982 extern __printf(2, 3)
983 int dev_notice(const struct device *dev, const char *fmt, ...);
984 extern __printf(2, 3)
985 int _dev_info(const struct device *dev, const char *fmt, ...);
989 static inline __printf(3, 0)
990 int dev_vprintk_emit(int level, const struct device *dev,
991 const char *fmt, va_list args)
993 static inline __printf(3, 4)
994 int dev_printk_emit(int level, const struct device *dev, const char *fmt, ...)
997 static inline int __dev_printk(const char *level, const struct device *dev,
998 struct va_format *vaf)
1000 static inline __printf(3, 4)
1001 int dev_printk(const char *level, const struct device *dev,
1002 const char *fmt, ...)
1005 static inline __printf(2, 3)
1006 int dev_emerg(const struct device *dev, const char *fmt, ...)
1008 static inline __printf(2, 3)
1009 int dev_crit(const struct device *dev, const char *fmt, ...)
1011 static inline __printf(2, 3)
1012 int dev_alert(const struct device *dev, const char *fmt, ...)
1014 static inline __printf(2, 3)
1015 int dev_err(const struct device *dev, const char *fmt, ...)
1017 static inline __printf(2, 3)
1018 int dev_warn(const struct device *dev, const char *fmt, ...)
1020 static inline __printf(2, 3)
1021 int dev_notice(const struct device *dev, const char *fmt, ...)
1023 static inline __printf(2, 3)
1024 int _dev_info(const struct device *dev, const char *fmt, ...)
1030 * Stupid hackaround for existing uses of non-printk uses dev_info
1032 * Note that the definition of dev_info below is actually _dev_info
1033 * and a macro is used to avoid redefining dev_info
1036 #define dev_info(dev, fmt, arg...) _dev_info(dev, fmt, ##arg)
1038 #if defined(CONFIG_DYNAMIC_DEBUG)
1039 #define dev_dbg(dev, format, ...) \
1041 dynamic_dev_dbg(dev, format, ##__VA_ARGS__); \
1043 #elif defined(DEBUG)
1044 #define dev_dbg(dev, format, arg...) \
1045 dev_printk(KERN_DEBUG, dev, format, ##arg)
1047 #define dev_dbg(dev, format, arg...) \
1050 dev_printk(KERN_DEBUG, dev, format, ##arg); \
1055 #define dev_level_ratelimited(dev_level, dev, fmt, ...) \
1057 static DEFINE_RATELIMIT_STATE(_rs, \
1058 DEFAULT_RATELIMIT_INTERVAL, \
1059 DEFAULT_RATELIMIT_BURST); \
1060 if (__ratelimit(&_rs)) \
1061 dev_level(dev, fmt, ##__VA_ARGS__); \
1064 #define dev_emerg_ratelimited(dev, fmt, ...) \
1065 dev_level_ratelimited(dev_emerg, dev, fmt, ##__VA_ARGS__)
1066 #define dev_alert_ratelimited(dev, fmt, ...) \
1067 dev_level_ratelimited(dev_alert, dev, fmt, ##__VA_ARGS__)
1068 #define dev_crit_ratelimited(dev, fmt, ...) \
1069 dev_level_ratelimited(dev_crit, dev, fmt, ##__VA_ARGS__)
1070 #define dev_err_ratelimited(dev, fmt, ...) \
1071 dev_level_ratelimited(dev_err, dev, fmt, ##__VA_ARGS__)
1072 #define dev_warn_ratelimited(dev, fmt, ...) \
1073 dev_level_ratelimited(dev_warn, dev, fmt, ##__VA_ARGS__)
1074 #define dev_notice_ratelimited(dev, fmt, ...) \
1075 dev_level_ratelimited(dev_notice, dev, fmt, ##__VA_ARGS__)
1076 #define dev_info_ratelimited(dev, fmt, ...) \
1077 dev_level_ratelimited(dev_info, dev, fmt, ##__VA_ARGS__)
1078 #if defined(CONFIG_DYNAMIC_DEBUG) || defined(DEBUG)
1079 #define dev_dbg_ratelimited(dev, fmt, ...) \
1081 static DEFINE_RATELIMIT_STATE(_rs, \
1082 DEFAULT_RATELIMIT_INTERVAL, \
1083 DEFAULT_RATELIMIT_BURST); \
1084 DEFINE_DYNAMIC_DEBUG_METADATA(descriptor, fmt); \
1085 if (unlikely(descriptor.flags & _DPRINTK_FLAGS_PRINT) && \
1086 __ratelimit(&_rs)) \
1087 __dynamic_pr_debug(&descriptor, pr_fmt(fmt), \
1091 #define dev_dbg_ratelimited(dev, fmt, ...) \
1092 no_printk(KERN_DEBUG pr_fmt(fmt), ##__VA_ARGS__)
1095 #ifdef VERBOSE_DEBUG
1096 #define dev_vdbg dev_dbg
1098 #define dev_vdbg(dev, format, arg...) \
1101 dev_printk(KERN_DEBUG, dev, format, ##arg); \
1107 * dev_WARN*() acts like dev_printk(), but with the key difference
1108 * of using a WARN/WARN_ON to get the message out, including the
1109 * file/line information and a backtrace.
1111 #define dev_WARN(dev, format, arg...) \
1112 WARN(1, "Device: %s\n" format, dev_driver_string(dev), ## arg);
1114 #define dev_WARN_ONCE(dev, condition, format, arg...) \
1115 WARN_ONCE(condition, "Device %s\n" format, \
1116 dev_driver_string(dev), ## arg)
1118 /* Create alias, so I can be autoloaded. */
1119 #define MODULE_ALIAS_CHARDEV(major,minor) \
1120 MODULE_ALIAS("char-major-" __stringify(major) "-" __stringify(minor))
1121 #define MODULE_ALIAS_CHARDEV_MAJOR(major) \
1122 MODULE_ALIAS("char-major-" __stringify(major) "-*")
1124 #ifdef CONFIG_SYSFS_DEPRECATED
1125 extern long sysfs_deprecated;
1127 #define sysfs_deprecated 0
1131 * module_driver() - Helper macro for drivers that don't do anything
1132 * special in module init/exit. This eliminates a lot of boilerplate.
1133 * Each module may only use this macro once, and calling it replaces
1134 * module_init() and module_exit().
1136 * @__driver: driver name
1137 * @__register: register function for this driver type
1138 * @__unregister: unregister function for this driver type
1139 * @...: Additional arguments to be passed to __register and __unregister.
1141 * Use this macro to construct bus specific macros for registering
1142 * drivers, and do not use it on its own.
1144 #define module_driver(__driver, __register, __unregister, ...) \
1145 static int __init __driver##_init(void) \
1147 return __register(&(__driver) , ##__VA_ARGS__); \
1149 module_init(__driver##_init); \
1150 static void __exit __driver##_exit(void) \
1152 __unregister(&(__driver) , ##__VA_ARGS__); \
1154 module_exit(__driver##_exit);
1156 #endif /* _DEVICE_H_ */