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;
45 struct bus_attribute {
46 struct attribute attr;
47 ssize_t (*show)(struct bus_type *bus, char *buf);
48 ssize_t (*store)(struct bus_type *bus, const char *buf, size_t count);
51 #define BUS_ATTR(_name, _mode, _show, _store) \
52 struct bus_attribute bus_attr_##_name = __ATTR(_name, _mode, _show, _store)
53 #define BUS_ATTR_RW(_name) \
54 struct bus_attribute bus_attr_##_name = __ATTR_RW(_name)
55 #define BUS_ATTR_RO(_name) \
56 struct bus_attribute bus_attr_##_name = __ATTR_RO(_name)
58 extern int __must_check bus_create_file(struct bus_type *,
59 struct bus_attribute *);
60 extern void bus_remove_file(struct bus_type *, struct bus_attribute *);
63 * struct bus_type - The bus type of the device
65 * @name: The name of the bus.
66 * @dev_name: Used for subsystems to enumerate devices like ("foo%u", dev->id).
67 * @dev_root: Default device to use as the parent.
68 * @dev_attrs: Default attributes of the devices on the bus.
69 * @bus_groups: Default attributes of the bus.
70 * @dev_groups: Default attributes of the devices on the bus.
71 * @drv_groups: Default attributes of the device drivers on the bus.
72 * @match: Called, perhaps multiple times, whenever a new device or driver
73 * is added for this bus. It should return a nonzero value if the
74 * given device can be handled by the given driver.
75 * @uevent: Called when a device is added, removed, or a few other things
76 * that generate uevents to add the environment variables.
77 * @probe: Called when a new device or driver add to this bus, and callback
78 * the specific driver's probe to initial the matched device.
79 * @remove: Called when a device removed from this bus.
80 * @shutdown: Called at shut-down time to quiesce the device.
82 * @online: Called to put the device back online (after offlining it).
83 * @offline: Called to put the device offline for hot-removal. May fail.
85 * @suspend: Called when a device on this bus wants to go to sleep mode.
86 * @resume: Called to bring a device on this bus out of sleep mode.
87 * @pm: Power management operations of this bus, callback the specific
88 * device driver's pm-ops.
89 * @iommu_ops: IOMMU specific operations for this bus, used to attach IOMMU
90 * driver implementations to a bus and allow the driver to do
92 * @p: The private data of the driver core, only the driver core can
94 * @lock_key: Lock class key for use by the lock validator
96 * A bus is a channel between the processor and one or more devices. For the
97 * purposes of the device model, all devices are connected via a bus, even if
98 * it is an internal, virtual, "platform" bus. Buses can plug into each other.
99 * A USB controller is usually a PCI device, for example. The device model
100 * represents the actual connections between buses and the devices they control.
101 * A bus is represented by the bus_type structure. It contains the name, the
102 * default attributes, the bus' methods, PM operations, and the driver core's
107 const char *dev_name;
108 struct device *dev_root;
109 struct device_attribute *dev_attrs; /* use dev_groups instead */
110 const struct attribute_group **bus_groups;
111 const struct attribute_group **dev_groups;
112 const struct attribute_group **drv_groups;
114 int (*match)(struct device *dev, struct device_driver *drv);
115 int (*uevent)(struct device *dev, struct kobj_uevent_env *env);
116 int (*probe)(struct device *dev);
117 int (*remove)(struct device *dev);
118 void (*shutdown)(struct device *dev);
120 int (*online)(struct device *dev);
121 int (*offline)(struct device *dev);
123 int (*suspend)(struct device *dev, pm_message_t state);
124 int (*resume)(struct device *dev);
126 const struct dev_pm_ops *pm;
128 const struct iommu_ops *iommu_ops;
130 struct subsys_private *p;
131 struct lock_class_key lock_key;
134 extern int __must_check bus_register(struct bus_type *bus);
136 extern void bus_unregister(struct bus_type *bus);
138 extern int __must_check bus_rescan_devices(struct bus_type *bus);
140 /* iterator helpers for buses */
141 struct subsys_dev_iter {
142 struct klist_iter ki;
143 const struct device_type *type;
145 void subsys_dev_iter_init(struct subsys_dev_iter *iter,
146 struct bus_type *subsys,
147 struct device *start,
148 const struct device_type *type);
149 struct device *subsys_dev_iter_next(struct subsys_dev_iter *iter);
150 void subsys_dev_iter_exit(struct subsys_dev_iter *iter);
152 int bus_for_each_dev(struct bus_type *bus, struct device *start, void *data,
153 int (*fn)(struct device *dev, void *data));
154 struct device *bus_find_device(struct bus_type *bus, struct device *start,
156 int (*match)(struct device *dev, void *data));
157 struct device *bus_find_device_by_name(struct bus_type *bus,
158 struct device *start,
160 struct device *subsys_find_device_by_id(struct bus_type *bus, unsigned int id,
161 struct device *hint);
162 int bus_for_each_drv(struct bus_type *bus, struct device_driver *start,
163 void *data, int (*fn)(struct device_driver *, void *));
164 void bus_sort_breadthfirst(struct bus_type *bus,
165 int (*compare)(const struct device *a,
166 const struct device *b));
168 * Bus notifiers: Get notified of addition/removal of devices
169 * and binding/unbinding of drivers to devices.
170 * In the long run, it should be a replacement for the platform
173 struct notifier_block;
175 extern int bus_register_notifier(struct bus_type *bus,
176 struct notifier_block *nb);
177 extern int bus_unregister_notifier(struct bus_type *bus,
178 struct notifier_block *nb);
180 /* All 4 notifers below get called with the target struct device *
181 * as an argument. Note that those functions are likely to be called
182 * with the device lock held in the core, so be careful.
184 #define BUS_NOTIFY_ADD_DEVICE 0x00000001 /* device added */
185 #define BUS_NOTIFY_DEL_DEVICE 0x00000002 /* device to be removed */
186 #define BUS_NOTIFY_REMOVED_DEVICE 0x00000003 /* device removed */
187 #define BUS_NOTIFY_BIND_DRIVER 0x00000004 /* driver about to be
189 #define BUS_NOTIFY_BOUND_DRIVER 0x00000005 /* driver bound to device */
190 #define BUS_NOTIFY_UNBIND_DRIVER 0x00000006 /* driver about to be
192 #define BUS_NOTIFY_UNBOUND_DRIVER 0x00000007 /* driver is unbound
195 extern struct kset *bus_get_kset(struct bus_type *bus);
196 extern struct klist *bus_get_device_klist(struct bus_type *bus);
199 * enum probe_type - device driver probe type to try
200 * Device drivers may opt in for special handling of their
201 * respective probe routines. This tells the core what to
204 * @PROBE_DEFAULT_STRATEGY: Drivers expect their probe routines
205 * to run synchronously with driver and device registration
206 * (with the exception of -EPROBE_DEFER handling - re-probing
207 * always ends up being done asynchronously) unless user
208 * explicitly requested asynchronous probing via module
210 * @PROBE_PREFER_ASYNCHRONOUS: Drivers for "slow" devices which
211 * probing order is not essential for booting the system may
212 * opt into executing their probes asynchronously.
214 * Note that the end goal is to switch the kernel to use asynchronous
215 * probing by default, so annotating drivers with
216 * %PROBE_PREFER_ASYNCHRONOUS is a temporary measure that allows us
217 * to speed up boot process while we are validating the rest of the
221 PROBE_DEFAULT_STRATEGY,
222 PROBE_PREFER_ASYNCHRONOUS,
226 * struct device_driver - The basic device driver structure
227 * @name: Name of the device driver.
228 * @bus: The bus which the device of this driver belongs to.
229 * @owner: The module owner.
230 * @mod_name: Used for built-in modules.
231 * @suppress_bind_attrs: Disables bind/unbind via sysfs.
232 * @probe_type: Type of the probe (synchronous or asynchronous) to use.
233 * @of_match_table: The open firmware table.
234 * @acpi_match_table: The ACPI match table.
235 * @probe: Called to query the existence of a specific device,
236 * whether this driver can work with it, and bind the driver
237 * to a specific device.
238 * @remove: Called when the device is removed from the system to
239 * unbind a device from this driver.
240 * @shutdown: Called at shut-down time to quiesce the device.
241 * @suspend: Called to put the device to sleep mode. Usually to a
243 * @resume: Called to bring a device from sleep mode.
244 * @groups: Default attributes that get created by the driver core
246 * @pm: Power management operations of the device which matched
248 * @p: Driver core's private data, no one other than the driver
249 * core can touch this.
251 * The device driver-model tracks all of the drivers known to the system.
252 * The main reason for this tracking is to enable the driver core to match
253 * up drivers with new devices. Once drivers are known objects within the
254 * system, however, a number of other things become possible. Device drivers
255 * can export information and configuration variables that are independent
256 * of any specific device.
258 struct device_driver {
260 struct bus_type *bus;
262 struct module *owner;
263 const char *mod_name; /* used for built-in modules */
265 bool suppress_bind_attrs; /* disables bind/unbind via sysfs */
266 enum probe_type probe_type;
268 const struct of_device_id *of_match_table;
269 const struct acpi_device_id *acpi_match_table;
271 int (*probe) (struct device *dev);
272 int (*remove) (struct device *dev);
273 void (*shutdown) (struct device *dev);
274 int (*suspend) (struct device *dev, pm_message_t state);
275 int (*resume) (struct device *dev);
276 const struct attribute_group **groups;
278 const struct dev_pm_ops *pm;
280 struct driver_private *p;
284 extern int __must_check driver_register(struct device_driver *drv);
285 extern void driver_unregister(struct device_driver *drv);
287 extern struct device_driver *driver_find(const char *name,
288 struct bus_type *bus);
289 extern int driver_probe_done(void);
290 extern void wait_for_device_probe(void);
293 /* sysfs interface for exporting driver attributes */
295 struct driver_attribute {
296 struct attribute attr;
297 ssize_t (*show)(struct device_driver *driver, char *buf);
298 ssize_t (*store)(struct device_driver *driver, const char *buf,
302 #define DRIVER_ATTR(_name, _mode, _show, _store) \
303 struct driver_attribute driver_attr_##_name = __ATTR(_name, _mode, _show, _store)
304 #define DRIVER_ATTR_RW(_name) \
305 struct driver_attribute driver_attr_##_name = __ATTR_RW(_name)
306 #define DRIVER_ATTR_RO(_name) \
307 struct driver_attribute driver_attr_##_name = __ATTR_RO(_name)
308 #define DRIVER_ATTR_WO(_name) \
309 struct driver_attribute driver_attr_##_name = __ATTR_WO(_name)
311 extern int __must_check driver_create_file(struct device_driver *driver,
312 const struct driver_attribute *attr);
313 extern void driver_remove_file(struct device_driver *driver,
314 const struct driver_attribute *attr);
316 extern int __must_check driver_for_each_device(struct device_driver *drv,
317 struct device *start,
319 int (*fn)(struct device *dev,
321 struct device *driver_find_device(struct device_driver *drv,
322 struct device *start, void *data,
323 int (*match)(struct device *dev, void *data));
326 * struct subsys_interface - interfaces to device functions
327 * @name: name of the device function
328 * @subsys: subsytem of the devices to attach to
329 * @node: the list of functions registered at the subsystem
330 * @add_dev: device hookup to device function handler
331 * @remove_dev: device hookup to device function handler
333 * Simple interfaces attached to a subsystem. Multiple interfaces can
334 * attach to a subsystem and its devices. Unlike drivers, they do not
335 * exclusively claim or control devices. Interfaces usually represent
336 * a specific functionality of a subsystem/class of devices.
338 struct subsys_interface {
340 struct bus_type *subsys;
341 struct list_head node;
342 int (*add_dev)(struct device *dev, struct subsys_interface *sif);
343 int (*remove_dev)(struct device *dev, struct subsys_interface *sif);
346 int subsys_interface_register(struct subsys_interface *sif);
347 void subsys_interface_unregister(struct subsys_interface *sif);
349 int subsys_system_register(struct bus_type *subsys,
350 const struct attribute_group **groups);
351 int subsys_virtual_register(struct bus_type *subsys,
352 const struct attribute_group **groups);
355 * struct class - device classes
356 * @name: Name of the class.
357 * @owner: The module owner.
358 * @class_attrs: Default attributes of this class.
359 * @dev_groups: Default attributes of the devices that belong to the class.
360 * @dev_kobj: The kobject that represents this class and links it into the hierarchy.
361 * @dev_uevent: Called when a device is added, removed from this class, or a
362 * few other things that generate uevents to add the environment
364 * @devnode: Callback to provide the devtmpfs.
365 * @class_release: Called to release this class.
366 * @dev_release: Called to release the device.
367 * @suspend: Used to put the device to sleep mode, usually to a low power
369 * @resume: Used to bring the device from the sleep mode.
370 * @ns_type: Callbacks so sysfs can detemine namespaces.
371 * @namespace: Namespace of the device belongs to this class.
372 * @pm: The default device power management operations of this class.
373 * @p: The private data of the driver core, no one other than the
374 * driver core can touch this.
376 * A class is a higher-level view of a device that abstracts out low-level
377 * implementation details. Drivers may see a SCSI disk or an ATA disk, but,
378 * at the class level, they are all simply disks. Classes allow user space
379 * to work with devices based on what they do, rather than how they are
380 * connected or how they work.
384 struct module *owner;
386 struct class_attribute *class_attrs;
387 const struct attribute_group **dev_groups;
388 struct kobject *dev_kobj;
390 int (*dev_uevent)(struct device *dev, struct kobj_uevent_env *env);
391 char *(*devnode)(struct device *dev, umode_t *mode);
393 void (*class_release)(struct class *class);
394 void (*dev_release)(struct device *dev);
396 int (*suspend)(struct device *dev, pm_message_t state);
397 int (*resume)(struct device *dev);
399 const struct kobj_ns_type_operations *ns_type;
400 const void *(*namespace)(struct device *dev);
402 const struct dev_pm_ops *pm;
404 struct subsys_private *p;
407 struct class_dev_iter {
408 struct klist_iter ki;
409 const struct device_type *type;
412 extern struct kobject *sysfs_dev_block_kobj;
413 extern struct kobject *sysfs_dev_char_kobj;
414 extern int __must_check __class_register(struct class *class,
415 struct lock_class_key *key);
416 extern void class_unregister(struct class *class);
418 /* This is a #define to keep the compiler from merging different
419 * instances of the __key variable */
420 #define class_register(class) \
422 static struct lock_class_key __key; \
423 __class_register(class, &__key); \
427 struct class_compat *class_compat_register(const char *name);
428 void class_compat_unregister(struct class_compat *cls);
429 int class_compat_create_link(struct class_compat *cls, struct device *dev,
430 struct device *device_link);
431 void class_compat_remove_link(struct class_compat *cls, struct device *dev,
432 struct device *device_link);
434 extern void class_dev_iter_init(struct class_dev_iter *iter,
436 struct device *start,
437 const struct device_type *type);
438 extern struct device *class_dev_iter_next(struct class_dev_iter *iter);
439 extern void class_dev_iter_exit(struct class_dev_iter *iter);
441 extern int class_for_each_device(struct class *class, struct device *start,
443 int (*fn)(struct device *dev, void *data));
444 extern struct device *class_find_device(struct class *class,
445 struct device *start, const void *data,
446 int (*match)(struct device *, const void *));
448 struct class_attribute {
449 struct attribute attr;
450 ssize_t (*show)(struct class *class, struct class_attribute *attr,
452 ssize_t (*store)(struct class *class, struct class_attribute *attr,
453 const char *buf, size_t count);
456 #define CLASS_ATTR(_name, _mode, _show, _store) \
457 struct class_attribute class_attr_##_name = __ATTR(_name, _mode, _show, _store)
458 #define CLASS_ATTR_RW(_name) \
459 struct class_attribute class_attr_##_name = __ATTR_RW(_name)
460 #define CLASS_ATTR_RO(_name) \
461 struct class_attribute class_attr_##_name = __ATTR_RO(_name)
463 extern int __must_check class_create_file_ns(struct class *class,
464 const struct class_attribute *attr,
466 extern void class_remove_file_ns(struct class *class,
467 const struct class_attribute *attr,
470 static inline int __must_check class_create_file(struct class *class,
471 const struct class_attribute *attr)
473 return class_create_file_ns(class, attr, NULL);
476 static inline void class_remove_file(struct class *class,
477 const struct class_attribute *attr)
479 return class_remove_file_ns(class, attr, NULL);
482 /* Simple class attribute that is just a static string */
483 struct class_attribute_string {
484 struct class_attribute attr;
488 /* Currently read-only only */
489 #define _CLASS_ATTR_STRING(_name, _mode, _str) \
490 { __ATTR(_name, _mode, show_class_attr_string, NULL), _str }
491 #define CLASS_ATTR_STRING(_name, _mode, _str) \
492 struct class_attribute_string class_attr_##_name = \
493 _CLASS_ATTR_STRING(_name, _mode, _str)
495 extern ssize_t show_class_attr_string(struct class *class, struct class_attribute *attr,
498 struct class_interface {
499 struct list_head node;
502 int (*add_dev) (struct device *, struct class_interface *);
503 void (*remove_dev) (struct device *, struct class_interface *);
506 extern int __must_check class_interface_register(struct class_interface *);
507 extern void class_interface_unregister(struct class_interface *);
509 extern struct class * __must_check __class_create(struct module *owner,
511 struct lock_class_key *key);
512 extern void class_destroy(struct class *cls);
514 /* This is a #define to keep the compiler from merging different
515 * instances of the __key variable */
516 #define class_create(owner, name) \
518 static struct lock_class_key __key; \
519 __class_create(owner, name, &__key); \
523 * The type of device, "struct device" is embedded in. A class
524 * or bus can contain devices of different types
525 * like "partitions" and "disks", "mouse" and "event".
526 * This identifies the device type and carries type-specific
527 * information, equivalent to the kobj_type of a kobject.
528 * If "name" is specified, the uevent will contain it in
529 * the DEVTYPE variable.
533 const struct attribute_group **groups;
534 int (*uevent)(struct device *dev, struct kobj_uevent_env *env);
535 char *(*devnode)(struct device *dev, umode_t *mode,
536 kuid_t *uid, kgid_t *gid);
537 void (*release)(struct device *dev);
539 const struct dev_pm_ops *pm;
542 /* interface for exporting device attributes */
543 struct device_attribute {
544 struct attribute attr;
545 ssize_t (*show)(struct device *dev, struct device_attribute *attr,
547 ssize_t (*store)(struct device *dev, struct device_attribute *attr,
548 const char *buf, size_t count);
551 struct dev_ext_attribute {
552 struct device_attribute attr;
556 ssize_t device_show_ulong(struct device *dev, struct device_attribute *attr,
558 ssize_t device_store_ulong(struct device *dev, struct device_attribute *attr,
559 const char *buf, size_t count);
560 ssize_t device_show_int(struct device *dev, struct device_attribute *attr,
562 ssize_t device_store_int(struct device *dev, struct device_attribute *attr,
563 const char *buf, size_t count);
564 ssize_t device_show_bool(struct device *dev, struct device_attribute *attr,
566 ssize_t device_store_bool(struct device *dev, struct device_attribute *attr,
567 const char *buf, size_t count);
569 #define DEVICE_ATTR(_name, _mode, _show, _store) \
570 struct device_attribute dev_attr_##_name = __ATTR(_name, _mode, _show, _store)
571 #define DEVICE_ATTR_RW(_name) \
572 struct device_attribute dev_attr_##_name = __ATTR_RW(_name)
573 #define DEVICE_ATTR_RO(_name) \
574 struct device_attribute dev_attr_##_name = __ATTR_RO(_name)
575 #define DEVICE_ATTR_WO(_name) \
576 struct device_attribute dev_attr_##_name = __ATTR_WO(_name)
577 #define DEVICE_ULONG_ATTR(_name, _mode, _var) \
578 struct dev_ext_attribute dev_attr_##_name = \
579 { __ATTR(_name, _mode, device_show_ulong, device_store_ulong), &(_var) }
580 #define DEVICE_INT_ATTR(_name, _mode, _var) \
581 struct dev_ext_attribute dev_attr_##_name = \
582 { __ATTR(_name, _mode, device_show_int, device_store_int), &(_var) }
583 #define DEVICE_BOOL_ATTR(_name, _mode, _var) \
584 struct dev_ext_attribute dev_attr_##_name = \
585 { __ATTR(_name, _mode, device_show_bool, device_store_bool), &(_var) }
586 #define DEVICE_ATTR_IGNORE_LOCKDEP(_name, _mode, _show, _store) \
587 struct device_attribute dev_attr_##_name = \
588 __ATTR_IGNORE_LOCKDEP(_name, _mode, _show, _store)
590 extern int device_create_file(struct device *device,
591 const struct device_attribute *entry);
592 extern void device_remove_file(struct device *dev,
593 const struct device_attribute *attr);
594 extern bool device_remove_file_self(struct device *dev,
595 const struct device_attribute *attr);
596 extern int __must_check device_create_bin_file(struct device *dev,
597 const struct bin_attribute *attr);
598 extern void device_remove_bin_file(struct device *dev,
599 const struct bin_attribute *attr);
601 /* device resource management */
602 typedef void (*dr_release_t)(struct device *dev, void *res);
603 typedef int (*dr_match_t)(struct device *dev, void *res, void *match_data);
605 #ifdef CONFIG_DEBUG_DEVRES
606 extern void *__devres_alloc(dr_release_t release, size_t size, gfp_t gfp,
608 #define devres_alloc(release, size, gfp) \
609 __devres_alloc(release, size, gfp, #release)
611 extern void *devres_alloc(dr_release_t release, size_t size, gfp_t gfp);
613 extern void devres_for_each_res(struct device *dev, dr_release_t release,
614 dr_match_t match, void *match_data,
615 void (*fn)(struct device *, void *, void *),
617 extern void devres_free(void *res);
618 extern void devres_add(struct device *dev, void *res);
619 extern void *devres_find(struct device *dev, dr_release_t release,
620 dr_match_t match, void *match_data);
621 extern void *devres_get(struct device *dev, void *new_res,
622 dr_match_t match, void *match_data);
623 extern void *devres_remove(struct device *dev, dr_release_t release,
624 dr_match_t match, void *match_data);
625 extern int devres_destroy(struct device *dev, dr_release_t release,
626 dr_match_t match, void *match_data);
627 extern int devres_release(struct device *dev, dr_release_t release,
628 dr_match_t match, void *match_data);
631 extern void * __must_check devres_open_group(struct device *dev, void *id,
633 extern void devres_close_group(struct device *dev, void *id);
634 extern void devres_remove_group(struct device *dev, void *id);
635 extern int devres_release_group(struct device *dev, void *id);
637 /* managed devm_k.alloc/kfree for device drivers */
638 extern void *devm_kmalloc(struct device *dev, size_t size, gfp_t gfp);
639 extern char *devm_kvasprintf(struct device *dev, gfp_t gfp, const char *fmt,
641 extern __printf(3, 4)
642 char *devm_kasprintf(struct device *dev, gfp_t gfp, const char *fmt, ...);
643 static inline void *devm_kzalloc(struct device *dev, size_t size, gfp_t gfp)
645 return devm_kmalloc(dev, size, gfp | __GFP_ZERO);
647 static inline void *devm_kmalloc_array(struct device *dev,
648 size_t n, size_t size, gfp_t flags)
650 if (size != 0 && n > SIZE_MAX / size)
652 return devm_kmalloc(dev, n * size, flags);
654 static inline void *devm_kcalloc(struct device *dev,
655 size_t n, size_t size, gfp_t flags)
657 return devm_kmalloc_array(dev, n, size, flags | __GFP_ZERO);
659 extern void devm_kfree(struct device *dev, void *p);
660 extern char *devm_kstrdup(struct device *dev, const char *s, gfp_t gfp);
661 extern void *devm_kmemdup(struct device *dev, const void *src, size_t len,
664 extern unsigned long devm_get_free_pages(struct device *dev,
665 gfp_t gfp_mask, unsigned int order);
666 extern void devm_free_pages(struct device *dev, unsigned long addr);
668 void __iomem *devm_ioremap_resource(struct device *dev, struct resource *res);
670 /* allows to add/remove a custom action to devres stack */
671 int devm_add_action(struct device *dev, void (*action)(void *), void *data);
672 void devm_remove_action(struct device *dev, void (*action)(void *), void *data);
674 struct device_dma_parameters {
676 * a low level driver may set these to teach IOMMU code about
679 unsigned int max_segment_size;
680 unsigned long segment_boundary_mask;
684 * struct device - The basic device structure
685 * @parent: The device's "parent" device, the device to which it is attached.
686 * In most cases, a parent device is some sort of bus or host
687 * controller. If parent is NULL, the device, is a top-level device,
688 * which is not usually what you want.
689 * @p: Holds the private data of the driver core portions of the device.
690 * See the comment of the struct device_private for detail.
691 * @kobj: A top-level, abstract class from which other classes are derived.
692 * @init_name: Initial name of the device.
693 * @type: The type of device.
694 * This identifies the device type and carries type-specific
696 * @mutex: Mutex to synchronize calls to its driver.
697 * @bus: Type of bus device is on.
698 * @driver: Which driver has allocated this
699 * @platform_data: Platform data specific to the device.
700 * Example: For devices on custom boards, as typical of embedded
701 * and SOC based hardware, Linux often uses platform_data to point
702 * to board-specific structures describing devices and how they
703 * are wired. That can include what ports are available, chip
704 * variants, which GPIO pins act in what additional roles, and so
705 * on. This shrinks the "Board Support Packages" (BSPs) and
706 * minimizes board-specific #ifdefs in drivers.
707 * @driver_data: Private pointer for driver specific info.
708 * @power: For device power management.
709 * See Documentation/power/devices.txt for details.
710 * @pm_domain: Provide callbacks that are executed during system suspend,
711 * hibernation, system resume and during runtime PM transitions
712 * along with subsystem-level and driver-level callbacks.
713 * @pins: For device pin management.
714 * See Documentation/pinctrl.txt for details.
715 * @numa_node: NUMA node this device is close to.
716 * @dma_mask: Dma mask (if dma'ble device).
717 * @coherent_dma_mask: Like dma_mask, but for alloc_coherent mapping as not all
718 * hardware supports 64-bit addresses for consistent allocations
720 * @dma_pfn_offset: offset of DMA memory range relatively of RAM
721 * @dma_parms: A low level driver may set these to teach IOMMU code about
722 * segment limitations.
723 * @dma_pools: Dma pools (if dma'ble device).
724 * @dma_mem: Internal for coherent mem override.
725 * @cma_area: Contiguous memory area for dma allocations
726 * @archdata: For arch-specific additions.
727 * @of_node: Associated device tree node.
728 * @fwnode: Associated device node supplied by platform firmware.
729 * @devt: For creating the sysfs "dev".
730 * @id: device instance
731 * @devres_lock: Spinlock to protect the resource of the device.
732 * @devres_head: The resources list of the device.
733 * @knode_class: The node used to add the device to the class list.
734 * @class: The class of the device.
735 * @groups: Optional attribute groups.
736 * @release: Callback to free the device after all references have
737 * gone away. This should be set by the allocator of the
738 * device (i.e. the bus driver that discovered the device).
739 * @iommu_group: IOMMU group the device belongs to.
741 * @offline_disabled: If set, the device is permanently online.
742 * @offline: Set after successful invocation of bus type's .offline().
744 * At the lowest level, every device in a Linux system is represented by an
745 * instance of struct device. The device structure contains the information
746 * that the device model core needs to model the system. Most subsystems,
747 * however, track additional information about the devices they host. As a
748 * result, it is rare for devices to be represented by bare device structures;
749 * instead, that structure, like kobject structures, is usually embedded within
750 * a higher-level representation of the device.
753 struct device *parent;
755 struct device_private *p;
758 const char *init_name; /* initial name of the device */
759 const struct device_type *type;
761 struct mutex mutex; /* mutex to synchronize calls to
765 struct bus_type *bus; /* type of bus device is on */
766 struct device_driver *driver; /* which driver has allocated this
768 void *platform_data; /* Platform specific data, device
769 core doesn't touch it */
770 void *driver_data; /* Driver data, set and get with
771 dev_set/get_drvdata */
772 struct dev_pm_info power;
773 struct dev_pm_domain *pm_domain;
775 #ifdef CONFIG_PINCTRL
776 struct dev_pin_info *pins;
780 int numa_node; /* NUMA node this device is close to */
782 u64 *dma_mask; /* dma mask (if dma'able device) */
783 u64 coherent_dma_mask;/* Like dma_mask, but for
784 alloc_coherent mappings as
785 not all hardware supports
786 64 bit addresses for consistent
787 allocations such descriptors. */
788 unsigned long dma_pfn_offset;
790 struct device_dma_parameters *dma_parms;
792 struct list_head dma_pools; /* dma pools (if dma'ble) */
794 struct dma_coherent_mem *dma_mem; /* internal for coherent mem
796 #ifdef CONFIG_DMA_CMA
797 struct cma *cma_area; /* contiguous memory area for dma
800 /* arch specific additions */
801 struct dev_archdata archdata;
803 struct device_node *of_node; /* associated device tree node */
804 struct fwnode_handle *fwnode; /* firmware device node */
806 dev_t devt; /* dev_t, creates the sysfs "dev" */
807 u32 id; /* device instance */
809 spinlock_t devres_lock;
810 struct list_head devres_head;
812 struct klist_node knode_class;
814 const struct attribute_group **groups; /* optional groups */
816 void (*release)(struct device *dev);
817 struct iommu_group *iommu_group;
819 bool offline_disabled:1;
823 static inline struct device *kobj_to_dev(struct kobject *kobj)
825 return container_of(kobj, struct device, kobj);
828 /* Get the wakeup routines, which depend on struct device */
829 #include <linux/pm_wakeup.h>
831 static inline const char *dev_name(const struct device *dev)
833 /* Use the init name until the kobject becomes available */
835 return dev->init_name;
837 return kobject_name(&dev->kobj);
840 extern __printf(2, 3)
841 int dev_set_name(struct device *dev, const char *name, ...);
844 static inline int dev_to_node(struct device *dev)
846 return dev->numa_node;
848 static inline void set_dev_node(struct device *dev, int node)
850 dev->numa_node = node;
853 static inline int dev_to_node(struct device *dev)
857 static inline void set_dev_node(struct device *dev, int node)
862 static inline void *dev_get_drvdata(const struct device *dev)
864 return dev->driver_data;
867 static inline void dev_set_drvdata(struct device *dev, void *data)
869 dev->driver_data = data;
872 static inline struct pm_subsys_data *dev_to_psd(struct device *dev)
874 return dev ? dev->power.subsys_data : NULL;
877 static inline unsigned int dev_get_uevent_suppress(const struct device *dev)
879 return dev->kobj.uevent_suppress;
882 static inline void dev_set_uevent_suppress(struct device *dev, int val)
884 dev->kobj.uevent_suppress = val;
887 static inline int device_is_registered(struct device *dev)
889 return dev->kobj.state_in_sysfs;
892 static inline void device_enable_async_suspend(struct device *dev)
894 if (!dev->power.is_prepared)
895 dev->power.async_suspend = true;
898 static inline void device_disable_async_suspend(struct device *dev)
900 if (!dev->power.is_prepared)
901 dev->power.async_suspend = false;
904 static inline bool device_async_suspend_enabled(struct device *dev)
906 return !!dev->power.async_suspend;
909 static inline void pm_suspend_ignore_children(struct device *dev, bool enable)
911 dev->power.ignore_children = enable;
914 static inline void dev_pm_syscore_device(struct device *dev, bool val)
916 #ifdef CONFIG_PM_SLEEP
917 dev->power.syscore = val;
921 static inline void device_lock(struct device *dev)
923 mutex_lock(&dev->mutex);
926 static inline int device_trylock(struct device *dev)
928 return mutex_trylock(&dev->mutex);
931 static inline void device_unlock(struct device *dev)
933 mutex_unlock(&dev->mutex);
936 static inline void device_lock_assert(struct device *dev)
938 lockdep_assert_held(&dev->mutex);
941 static inline struct device_node *dev_of_node(struct device *dev)
943 if (!IS_ENABLED(CONFIG_OF))
948 void driver_init(void);
951 * High level routines for use by the bus drivers
953 extern int __must_check device_register(struct device *dev);
954 extern void device_unregister(struct device *dev);
955 extern void device_initialize(struct device *dev);
956 extern int __must_check device_add(struct device *dev);
957 extern void device_del(struct device *dev);
958 extern int device_for_each_child(struct device *dev, void *data,
959 int (*fn)(struct device *dev, void *data));
960 extern struct device *device_find_child(struct device *dev, void *data,
961 int (*match)(struct device *dev, void *data));
962 extern int device_rename(struct device *dev, const char *new_name);
963 extern int device_move(struct device *dev, struct device *new_parent,
964 enum dpm_order dpm_order);
965 extern const char *device_get_devnode(struct device *dev,
966 umode_t *mode, kuid_t *uid, kgid_t *gid,
969 static inline bool device_supports_offline(struct device *dev)
971 return dev->bus && dev->bus->offline && dev->bus->online;
974 extern void lock_device_hotplug(void);
975 extern void unlock_device_hotplug(void);
976 extern int lock_device_hotplug_sysfs(void);
977 extern int device_offline(struct device *dev);
978 extern int device_online(struct device *dev);
979 extern void set_primary_fwnode(struct device *dev, struct fwnode_handle *fwnode);
980 extern void set_secondary_fwnode(struct device *dev, struct fwnode_handle *fwnode);
983 * Root device objects for grouping under /sys/devices
985 extern struct device *__root_device_register(const char *name,
986 struct module *owner);
988 /* This is a macro to avoid include problems with THIS_MODULE */
989 #define root_device_register(name) \
990 __root_device_register(name, THIS_MODULE)
992 extern void root_device_unregister(struct device *root);
994 static inline void *dev_get_platdata(const struct device *dev)
996 return dev->platform_data;
1000 * Manual binding of a device to driver. See drivers/base/bus.c
1001 * for information on use.
1003 extern int __must_check device_bind_driver(struct device *dev);
1004 extern void device_release_driver(struct device *dev);
1005 extern int __must_check device_attach(struct device *dev);
1006 extern int __must_check driver_attach(struct device_driver *drv);
1007 extern void device_initial_probe(struct device *dev);
1008 extern int __must_check device_reprobe(struct device *dev);
1011 * Easy functions for dynamically creating devices on the fly
1013 extern struct device *device_create_vargs(struct class *cls,
1014 struct device *parent,
1019 extern __printf(5, 6)
1020 struct device *device_create(struct class *cls, struct device *parent,
1021 dev_t devt, void *drvdata,
1022 const char *fmt, ...);
1023 extern __printf(6, 7)
1024 struct device *device_create_with_groups(struct class *cls,
1025 struct device *parent, dev_t devt, void *drvdata,
1026 const struct attribute_group **groups,
1027 const char *fmt, ...);
1028 extern void device_destroy(struct class *cls, dev_t devt);
1031 * Platform "fixup" functions - allow the platform to have their say
1032 * about devices and actions that the general device layer doesn't
1035 /* Notify platform of device discovery */
1036 extern int (*platform_notify)(struct device *dev);
1038 extern int (*platform_notify_remove)(struct device *dev);
1042 * get_device - atomically increment the reference count for the device.
1045 extern struct device *get_device(struct device *dev);
1046 extern void put_device(struct device *dev);
1048 #ifdef CONFIG_DEVTMPFS
1049 extern int devtmpfs_create_node(struct device *dev);
1050 extern int devtmpfs_delete_node(struct device *dev);
1051 extern int devtmpfs_mount(const char *mntdir);
1053 static inline int devtmpfs_create_node(struct device *dev) { return 0; }
1054 static inline int devtmpfs_delete_node(struct device *dev) { return 0; }
1055 static inline int devtmpfs_mount(const char *mountpoint) { return 0; }
1058 /* drivers/base/power/shutdown.c */
1059 extern void device_shutdown(void);
1061 /* debugging and troubleshooting/diagnostic helpers. */
1062 extern const char *dev_driver_string(const struct device *dev);
1065 #ifdef CONFIG_PRINTK
1067 extern __printf(3, 0)
1068 int dev_vprintk_emit(int level, const struct device *dev,
1069 const char *fmt, va_list args);
1070 extern __printf(3, 4)
1071 int dev_printk_emit(int level, const struct device *dev, const char *fmt, ...);
1073 extern __printf(3, 4)
1074 void dev_printk(const char *level, const struct device *dev,
1075 const char *fmt, ...);
1076 extern __printf(2, 3)
1077 void dev_emerg(const struct device *dev, const char *fmt, ...);
1078 extern __printf(2, 3)
1079 void dev_alert(const struct device *dev, const char *fmt, ...);
1080 extern __printf(2, 3)
1081 void dev_crit(const struct device *dev, const char *fmt, ...);
1082 extern __printf(2, 3)
1083 void dev_err(const struct device *dev, const char *fmt, ...);
1084 extern __printf(2, 3)
1085 void dev_warn(const struct device *dev, const char *fmt, ...);
1086 extern __printf(2, 3)
1087 void dev_notice(const struct device *dev, const char *fmt, ...);
1088 extern __printf(2, 3)
1089 void _dev_info(const struct device *dev, const char *fmt, ...);
1093 static inline __printf(3, 0)
1094 int dev_vprintk_emit(int level, const struct device *dev,
1095 const char *fmt, va_list args)
1097 static inline __printf(3, 4)
1098 int dev_printk_emit(int level, const struct device *dev, const char *fmt, ...)
1101 static inline void __dev_printk(const char *level, const struct device *dev,
1102 struct va_format *vaf)
1104 static inline __printf(3, 4)
1105 void dev_printk(const char *level, const struct device *dev,
1106 const char *fmt, ...)
1109 static inline __printf(2, 3)
1110 void dev_emerg(const struct device *dev, const char *fmt, ...)
1112 static inline __printf(2, 3)
1113 void dev_crit(const struct device *dev, const char *fmt, ...)
1115 static inline __printf(2, 3)
1116 void dev_alert(const struct device *dev, const char *fmt, ...)
1118 static inline __printf(2, 3)
1119 void dev_err(const struct device *dev, const char *fmt, ...)
1121 static inline __printf(2, 3)
1122 void dev_warn(const struct device *dev, const char *fmt, ...)
1124 static inline __printf(2, 3)
1125 void dev_notice(const struct device *dev, const char *fmt, ...)
1127 static inline __printf(2, 3)
1128 void _dev_info(const struct device *dev, const char *fmt, ...)
1134 * Stupid hackaround for existing uses of non-printk uses dev_info
1136 * Note that the definition of dev_info below is actually _dev_info
1137 * and a macro is used to avoid redefining dev_info
1140 #define dev_info(dev, fmt, arg...) _dev_info(dev, fmt, ##arg)
1142 #if defined(CONFIG_DYNAMIC_DEBUG)
1143 #define dev_dbg(dev, format, ...) \
1145 dynamic_dev_dbg(dev, format, ##__VA_ARGS__); \
1147 #elif defined(DEBUG)
1148 #define dev_dbg(dev, format, arg...) \
1149 dev_printk(KERN_DEBUG, dev, format, ##arg)
1151 #define dev_dbg(dev, format, arg...) \
1154 dev_printk(KERN_DEBUG, dev, format, ##arg); \
1158 #ifdef CONFIG_PRINTK
1159 #define dev_level_once(dev_level, dev, fmt, ...) \
1161 static bool __print_once __read_mostly; \
1163 if (!__print_once) { \
1164 __print_once = true; \
1165 dev_level(dev, fmt, ##__VA_ARGS__); \
1169 #define dev_level_once(dev_level, dev, fmt, ...) \
1172 dev_level(dev, fmt, ##__VA_ARGS__); \
1176 #define dev_emerg_once(dev, fmt, ...) \
1177 dev_level_once(dev_emerg, dev, fmt, ##__VA_ARGS__)
1178 #define dev_alert_once(dev, fmt, ...) \
1179 dev_level_once(dev_alert, dev, fmt, ##__VA_ARGS__)
1180 #define dev_crit_once(dev, fmt, ...) \
1181 dev_level_once(dev_crit, dev, fmt, ##__VA_ARGS__)
1182 #define dev_err_once(dev, fmt, ...) \
1183 dev_level_once(dev_err, dev, fmt, ##__VA_ARGS__)
1184 #define dev_warn_once(dev, fmt, ...) \
1185 dev_level_once(dev_warn, dev, fmt, ##__VA_ARGS__)
1186 #define dev_notice_once(dev, fmt, ...) \
1187 dev_level_once(dev_notice, dev, fmt, ##__VA_ARGS__)
1188 #define dev_info_once(dev, fmt, ...) \
1189 dev_level_once(dev_info, dev, fmt, ##__VA_ARGS__)
1190 #define dev_dbg_once(dev, fmt, ...) \
1191 dev_level_once(dev_dbg, dev, fmt, ##__VA_ARGS__)
1193 #define dev_level_ratelimited(dev_level, dev, fmt, ...) \
1195 static DEFINE_RATELIMIT_STATE(_rs, \
1196 DEFAULT_RATELIMIT_INTERVAL, \
1197 DEFAULT_RATELIMIT_BURST); \
1198 if (__ratelimit(&_rs)) \
1199 dev_level(dev, fmt, ##__VA_ARGS__); \
1202 #define dev_emerg_ratelimited(dev, fmt, ...) \
1203 dev_level_ratelimited(dev_emerg, dev, fmt, ##__VA_ARGS__)
1204 #define dev_alert_ratelimited(dev, fmt, ...) \
1205 dev_level_ratelimited(dev_alert, dev, fmt, ##__VA_ARGS__)
1206 #define dev_crit_ratelimited(dev, fmt, ...) \
1207 dev_level_ratelimited(dev_crit, dev, fmt, ##__VA_ARGS__)
1208 #define dev_err_ratelimited(dev, fmt, ...) \
1209 dev_level_ratelimited(dev_err, dev, fmt, ##__VA_ARGS__)
1210 #define dev_warn_ratelimited(dev, fmt, ...) \
1211 dev_level_ratelimited(dev_warn, dev, fmt, ##__VA_ARGS__)
1212 #define dev_notice_ratelimited(dev, fmt, ...) \
1213 dev_level_ratelimited(dev_notice, dev, fmt, ##__VA_ARGS__)
1214 #define dev_info_ratelimited(dev, fmt, ...) \
1215 dev_level_ratelimited(dev_info, dev, fmt, ##__VA_ARGS__)
1216 #if defined(CONFIG_DYNAMIC_DEBUG)
1217 /* descriptor check is first to prevent flooding with "callbacks suppressed" */
1218 #define dev_dbg_ratelimited(dev, fmt, ...) \
1220 static DEFINE_RATELIMIT_STATE(_rs, \
1221 DEFAULT_RATELIMIT_INTERVAL, \
1222 DEFAULT_RATELIMIT_BURST); \
1223 DEFINE_DYNAMIC_DEBUG_METADATA(descriptor, fmt); \
1224 if (unlikely(descriptor.flags & _DPRINTK_FLAGS_PRINT) && \
1225 __ratelimit(&_rs)) \
1226 __dynamic_dev_dbg(&descriptor, dev, fmt, \
1229 #elif defined(DEBUG)
1230 #define dev_dbg_ratelimited(dev, fmt, ...) \
1232 static DEFINE_RATELIMIT_STATE(_rs, \
1233 DEFAULT_RATELIMIT_INTERVAL, \
1234 DEFAULT_RATELIMIT_BURST); \
1235 if (__ratelimit(&_rs)) \
1236 dev_printk(KERN_DEBUG, dev, fmt, ##__VA_ARGS__); \
1239 #define dev_dbg_ratelimited(dev, fmt, ...) \
1240 no_printk(KERN_DEBUG pr_fmt(fmt), ##__VA_ARGS__)
1243 #ifdef VERBOSE_DEBUG
1244 #define dev_vdbg dev_dbg
1246 #define dev_vdbg(dev, format, arg...) \
1249 dev_printk(KERN_DEBUG, dev, format, ##arg); \
1254 * dev_WARN*() acts like dev_printk(), but with the key difference of
1255 * using WARN/WARN_ONCE to include file/line information and a backtrace.
1257 #define dev_WARN(dev, format, arg...) \
1258 WARN(1, "%s %s: " format, dev_driver_string(dev), dev_name(dev), ## arg);
1260 #define dev_WARN_ONCE(dev, condition, format, arg...) \
1261 WARN_ONCE(condition, "%s %s: " format, \
1262 dev_driver_string(dev), dev_name(dev), ## arg)
1264 /* Create alias, so I can be autoloaded. */
1265 #define MODULE_ALIAS_CHARDEV(major,minor) \
1266 MODULE_ALIAS("char-major-" __stringify(major) "-" __stringify(minor))
1267 #define MODULE_ALIAS_CHARDEV_MAJOR(major) \
1268 MODULE_ALIAS("char-major-" __stringify(major) "-*")
1270 #ifdef CONFIG_SYSFS_DEPRECATED
1271 extern long sysfs_deprecated;
1273 #define sysfs_deprecated 0
1277 * module_driver() - Helper macro for drivers that don't do anything
1278 * special in module init/exit. This eliminates a lot of boilerplate.
1279 * Each module may only use this macro once, and calling it replaces
1280 * module_init() and module_exit().
1282 * @__driver: driver name
1283 * @__register: register function for this driver type
1284 * @__unregister: unregister function for this driver type
1285 * @...: Additional arguments to be passed to __register and __unregister.
1287 * Use this macro to construct bus specific macros for registering
1288 * drivers, and do not use it on its own.
1290 #define module_driver(__driver, __register, __unregister, ...) \
1291 static int __init __driver##_init(void) \
1293 return __register(&(__driver) , ##__VA_ARGS__); \
1295 module_init(__driver##_init); \
1296 static void __exit __driver##_exit(void) \
1298 __unregister(&(__driver) , ##__VA_ARGS__); \
1300 module_exit(__driver##_exit);
1302 #endif /* _DEVICE_H_ */