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
194 #define BUS_NOTIFY_DRIVER_NOT_BOUND 0x00000008 /* driver fails to be bound */
196 extern struct kset *bus_get_kset(struct bus_type *bus);
197 extern struct klist *bus_get_device_klist(struct bus_type *bus);
200 * enum probe_type - device driver probe type to try
201 * Device drivers may opt in for special handling of their
202 * respective probe routines. This tells the core what to
205 * @PROBE_DEFAULT_STRATEGY: Used by drivers that work equally well
206 * whether probed synchronously or asynchronously.
207 * @PROBE_PREFER_ASYNCHRONOUS: Drivers for "slow" devices which
208 * probing order is not essential for booting the system may
209 * opt into executing their probes asynchronously.
210 * @PROBE_FORCE_SYNCHRONOUS: Use this to annotate drivers that need
211 * their probe routines to run synchronously with driver and
212 * device registration (with the exception of -EPROBE_DEFER
213 * handling - re-probing always ends up being done asynchronously).
215 * Note that the end goal is to switch the kernel to use asynchronous
216 * probing by default, so annotating drivers with
217 * %PROBE_PREFER_ASYNCHRONOUS is a temporary measure that allows us
218 * to speed up boot process while we are validating the rest of the
222 PROBE_DEFAULT_STRATEGY,
223 PROBE_PREFER_ASYNCHRONOUS,
224 PROBE_FORCE_SYNCHRONOUS,
228 * struct device_driver - The basic device driver structure
229 * @name: Name of the device driver.
230 * @bus: The bus which the device of this driver belongs to.
231 * @owner: The module owner.
232 * @mod_name: Used for built-in modules.
233 * @suppress_bind_attrs: Disables bind/unbind via sysfs.
234 * @probe_type: Type of the probe (synchronous or asynchronous) to use.
235 * @of_match_table: The open firmware table.
236 * @acpi_match_table: The ACPI match table.
237 * @probe: Called to query the existence of a specific device,
238 * whether this driver can work with it, and bind the driver
239 * to a specific device.
240 * @remove: Called when the device is removed from the system to
241 * unbind a device from this driver.
242 * @shutdown: Called at shut-down time to quiesce the device.
243 * @suspend: Called to put the device to sleep mode. Usually to a
245 * @resume: Called to bring a device from sleep mode.
246 * @groups: Default attributes that get created by the driver core
248 * @pm: Power management operations of the device which matched
250 * @p: Driver core's private data, no one other than the driver
251 * core can touch this.
253 * The device driver-model tracks all of the drivers known to the system.
254 * The main reason for this tracking is to enable the driver core to match
255 * up drivers with new devices. Once drivers are known objects within the
256 * system, however, a number of other things become possible. Device drivers
257 * can export information and configuration variables that are independent
258 * of any specific device.
260 struct device_driver {
262 struct bus_type *bus;
264 struct module *owner;
265 const char *mod_name; /* used for built-in modules */
267 bool suppress_bind_attrs; /* disables bind/unbind via sysfs */
268 enum probe_type probe_type;
270 const struct of_device_id *of_match_table;
271 const struct acpi_device_id *acpi_match_table;
273 int (*probe) (struct device *dev);
274 int (*remove) (struct device *dev);
275 void (*shutdown) (struct device *dev);
276 int (*suspend) (struct device *dev, pm_message_t state);
277 int (*resume) (struct device *dev);
278 const struct attribute_group **groups;
280 const struct dev_pm_ops *pm;
282 struct driver_private *p;
286 extern int __must_check driver_register(struct device_driver *drv);
287 extern void driver_unregister(struct device_driver *drv);
289 extern struct device_driver *driver_find(const char *name,
290 struct bus_type *bus);
291 extern int driver_probe_done(void);
292 extern void wait_for_device_probe(void);
295 /* sysfs interface for exporting driver attributes */
297 struct driver_attribute {
298 struct attribute attr;
299 ssize_t (*show)(struct device_driver *driver, char *buf);
300 ssize_t (*store)(struct device_driver *driver, const char *buf,
304 #define DRIVER_ATTR(_name, _mode, _show, _store) \
305 struct driver_attribute driver_attr_##_name = __ATTR(_name, _mode, _show, _store)
306 #define DRIVER_ATTR_RW(_name) \
307 struct driver_attribute driver_attr_##_name = __ATTR_RW(_name)
308 #define DRIVER_ATTR_RO(_name) \
309 struct driver_attribute driver_attr_##_name = __ATTR_RO(_name)
310 #define DRIVER_ATTR_WO(_name) \
311 struct driver_attribute driver_attr_##_name = __ATTR_WO(_name)
313 extern int __must_check driver_create_file(struct device_driver *driver,
314 const struct driver_attribute *attr);
315 extern void driver_remove_file(struct device_driver *driver,
316 const struct driver_attribute *attr);
318 extern int __must_check driver_for_each_device(struct device_driver *drv,
319 struct device *start,
321 int (*fn)(struct device *dev,
323 struct device *driver_find_device(struct device_driver *drv,
324 struct device *start, void *data,
325 int (*match)(struct device *dev, void *data));
328 * struct subsys_interface - interfaces to device functions
329 * @name: name of the device function
330 * @subsys: subsytem of the devices to attach to
331 * @node: the list of functions registered at the subsystem
332 * @add_dev: device hookup to device function handler
333 * @remove_dev: device hookup to device function handler
335 * Simple interfaces attached to a subsystem. Multiple interfaces can
336 * attach to a subsystem and its devices. Unlike drivers, they do not
337 * exclusively claim or control devices. Interfaces usually represent
338 * a specific functionality of a subsystem/class of devices.
340 struct subsys_interface {
342 struct bus_type *subsys;
343 struct list_head node;
344 int (*add_dev)(struct device *dev, struct subsys_interface *sif);
345 void (*remove_dev)(struct device *dev, struct subsys_interface *sif);
348 int subsys_interface_register(struct subsys_interface *sif);
349 void subsys_interface_unregister(struct subsys_interface *sif);
351 int subsys_system_register(struct bus_type *subsys,
352 const struct attribute_group **groups);
353 int subsys_virtual_register(struct bus_type *subsys,
354 const struct attribute_group **groups);
357 * struct class - device classes
358 * @name: Name of the class.
359 * @owner: The module owner.
360 * @class_attrs: Default attributes of this class.
361 * @dev_groups: Default attributes of the devices that belong to the class.
362 * @dev_kobj: The kobject that represents this class and links it into the hierarchy.
363 * @dev_uevent: Called when a device is added, removed from this class, or a
364 * few other things that generate uevents to add the environment
366 * @devnode: Callback to provide the devtmpfs.
367 * @class_release: Called to release this class.
368 * @dev_release: Called to release the device.
369 * @suspend: Used to put the device to sleep mode, usually to a low power
371 * @resume: Used to bring the device from the sleep mode.
372 * @ns_type: Callbacks so sysfs can detemine namespaces.
373 * @namespace: Namespace of the device belongs to this class.
374 * @pm: The default device power management operations of this class.
375 * @p: The private data of the driver core, no one other than the
376 * driver core can touch this.
378 * A class is a higher-level view of a device that abstracts out low-level
379 * implementation details. Drivers may see a SCSI disk or an ATA disk, but,
380 * at the class level, they are all simply disks. Classes allow user space
381 * to work with devices based on what they do, rather than how they are
382 * connected or how they work.
386 struct module *owner;
388 struct class_attribute *class_attrs;
389 const struct attribute_group **dev_groups;
390 struct kobject *dev_kobj;
392 int (*dev_uevent)(struct device *dev, struct kobj_uevent_env *env);
393 char *(*devnode)(struct device *dev, umode_t *mode);
395 void (*class_release)(struct class *class);
396 void (*dev_release)(struct device *dev);
398 int (*suspend)(struct device *dev, pm_message_t state);
399 int (*resume)(struct device *dev);
401 const struct kobj_ns_type_operations *ns_type;
402 const void *(*namespace)(struct device *dev);
404 const struct dev_pm_ops *pm;
406 struct subsys_private *p;
409 struct class_dev_iter {
410 struct klist_iter ki;
411 const struct device_type *type;
414 extern struct kobject *sysfs_dev_block_kobj;
415 extern struct kobject *sysfs_dev_char_kobj;
416 extern int __must_check __class_register(struct class *class,
417 struct lock_class_key *key);
418 extern void class_unregister(struct class *class);
420 /* This is a #define to keep the compiler from merging different
421 * instances of the __key variable */
422 #define class_register(class) \
424 static struct lock_class_key __key; \
425 __class_register(class, &__key); \
429 struct class_compat *class_compat_register(const char *name);
430 void class_compat_unregister(struct class_compat *cls);
431 int class_compat_create_link(struct class_compat *cls, struct device *dev,
432 struct device *device_link);
433 void class_compat_remove_link(struct class_compat *cls, struct device *dev,
434 struct device *device_link);
436 extern void class_dev_iter_init(struct class_dev_iter *iter,
438 struct device *start,
439 const struct device_type *type);
440 extern struct device *class_dev_iter_next(struct class_dev_iter *iter);
441 extern void class_dev_iter_exit(struct class_dev_iter *iter);
443 extern int class_for_each_device(struct class *class, struct device *start,
445 int (*fn)(struct device *dev, void *data));
446 extern struct device *class_find_device(struct class *class,
447 struct device *start, const void *data,
448 int (*match)(struct device *, const void *));
450 struct class_attribute {
451 struct attribute attr;
452 ssize_t (*show)(struct class *class, struct class_attribute *attr,
454 ssize_t (*store)(struct class *class, struct class_attribute *attr,
455 const char *buf, size_t count);
458 #define CLASS_ATTR(_name, _mode, _show, _store) \
459 struct class_attribute class_attr_##_name = __ATTR(_name, _mode, _show, _store)
460 #define CLASS_ATTR_RW(_name) \
461 struct class_attribute class_attr_##_name = __ATTR_RW(_name)
462 #define CLASS_ATTR_RO(_name) \
463 struct class_attribute class_attr_##_name = __ATTR_RO(_name)
465 extern int __must_check class_create_file_ns(struct class *class,
466 const struct class_attribute *attr,
468 extern void class_remove_file_ns(struct class *class,
469 const struct class_attribute *attr,
472 static inline int __must_check class_create_file(struct class *class,
473 const struct class_attribute *attr)
475 return class_create_file_ns(class, attr, NULL);
478 static inline void class_remove_file(struct class *class,
479 const struct class_attribute *attr)
481 return class_remove_file_ns(class, attr, NULL);
484 /* Simple class attribute that is just a static string */
485 struct class_attribute_string {
486 struct class_attribute attr;
490 /* Currently read-only only */
491 #define _CLASS_ATTR_STRING(_name, _mode, _str) \
492 { __ATTR(_name, _mode, show_class_attr_string, NULL), _str }
493 #define CLASS_ATTR_STRING(_name, _mode, _str) \
494 struct class_attribute_string class_attr_##_name = \
495 _CLASS_ATTR_STRING(_name, _mode, _str)
497 extern ssize_t show_class_attr_string(struct class *class, struct class_attribute *attr,
500 struct class_interface {
501 struct list_head node;
504 int (*add_dev) (struct device *, struct class_interface *);
505 void (*remove_dev) (struct device *, struct class_interface *);
508 extern int __must_check class_interface_register(struct class_interface *);
509 extern void class_interface_unregister(struct class_interface *);
511 extern struct class * __must_check __class_create(struct module *owner,
513 struct lock_class_key *key);
514 extern void class_destroy(struct class *cls);
516 /* This is a #define to keep the compiler from merging different
517 * instances of the __key variable */
518 #define class_create(owner, name) \
520 static struct lock_class_key __key; \
521 __class_create(owner, name, &__key); \
525 * The type of device, "struct device" is embedded in. A class
526 * or bus can contain devices of different types
527 * like "partitions" and "disks", "mouse" and "event".
528 * This identifies the device type and carries type-specific
529 * information, equivalent to the kobj_type of a kobject.
530 * If "name" is specified, the uevent will contain it in
531 * the DEVTYPE variable.
535 const struct attribute_group **groups;
536 int (*uevent)(struct device *dev, struct kobj_uevent_env *env);
537 char *(*devnode)(struct device *dev, umode_t *mode,
538 kuid_t *uid, kgid_t *gid);
539 void (*release)(struct device *dev);
541 const struct dev_pm_ops *pm;
544 /* interface for exporting device attributes */
545 struct device_attribute {
546 struct attribute attr;
547 ssize_t (*show)(struct device *dev, struct device_attribute *attr,
549 ssize_t (*store)(struct device *dev, struct device_attribute *attr,
550 const char *buf, size_t count);
553 struct dev_ext_attribute {
554 struct device_attribute attr;
558 ssize_t device_show_ulong(struct device *dev, struct device_attribute *attr,
560 ssize_t device_store_ulong(struct device *dev, struct device_attribute *attr,
561 const char *buf, size_t count);
562 ssize_t device_show_int(struct device *dev, struct device_attribute *attr,
564 ssize_t device_store_int(struct device *dev, struct device_attribute *attr,
565 const char *buf, size_t count);
566 ssize_t device_show_bool(struct device *dev, struct device_attribute *attr,
568 ssize_t device_store_bool(struct device *dev, struct device_attribute *attr,
569 const char *buf, size_t count);
571 #define DEVICE_ATTR(_name, _mode, _show, _store) \
572 struct device_attribute dev_attr_##_name = __ATTR(_name, _mode, _show, _store)
573 #define DEVICE_ATTR_RW(_name) \
574 struct device_attribute dev_attr_##_name = __ATTR_RW(_name)
575 #define DEVICE_ATTR_RO(_name) \
576 struct device_attribute dev_attr_##_name = __ATTR_RO(_name)
577 #define DEVICE_ATTR_WO(_name) \
578 struct device_attribute dev_attr_##_name = __ATTR_WO(_name)
579 #define DEVICE_ULONG_ATTR(_name, _mode, _var) \
580 struct dev_ext_attribute dev_attr_##_name = \
581 { __ATTR(_name, _mode, device_show_ulong, device_store_ulong), &(_var) }
582 #define DEVICE_INT_ATTR(_name, _mode, _var) \
583 struct dev_ext_attribute dev_attr_##_name = \
584 { __ATTR(_name, _mode, device_show_int, device_store_int), &(_var) }
585 #define DEVICE_BOOL_ATTR(_name, _mode, _var) \
586 struct dev_ext_attribute dev_attr_##_name = \
587 { __ATTR(_name, _mode, device_show_bool, device_store_bool), &(_var) }
588 #define DEVICE_ATTR_IGNORE_LOCKDEP(_name, _mode, _show, _store) \
589 struct device_attribute dev_attr_##_name = \
590 __ATTR_IGNORE_LOCKDEP(_name, _mode, _show, _store)
592 extern int device_create_file(struct device *device,
593 const struct device_attribute *entry);
594 extern void device_remove_file(struct device *dev,
595 const struct device_attribute *attr);
596 extern bool device_remove_file_self(struct device *dev,
597 const struct device_attribute *attr);
598 extern int __must_check device_create_bin_file(struct device *dev,
599 const struct bin_attribute *attr);
600 extern void device_remove_bin_file(struct device *dev,
601 const struct bin_attribute *attr);
603 /* device resource management */
604 typedef void (*dr_release_t)(struct device *dev, void *res);
605 typedef int (*dr_match_t)(struct device *dev, void *res, void *match_data);
607 #ifdef CONFIG_DEBUG_DEVRES
608 extern void *__devres_alloc_node(dr_release_t release, size_t size, gfp_t gfp,
609 int nid, const char *name);
610 #define devres_alloc(release, size, gfp) \
611 __devres_alloc_node(release, size, gfp, NUMA_NO_NODE, #release)
612 #define devres_alloc_node(release, size, gfp, nid) \
613 __devres_alloc_node(release, size, gfp, nid, #release)
615 extern void *devres_alloc_node(dr_release_t release, size_t size, gfp_t gfp,
617 static inline void *devres_alloc(dr_release_t release, size_t size, gfp_t gfp)
619 return devres_alloc_node(release, size, gfp, NUMA_NO_NODE);
623 extern void devres_for_each_res(struct device *dev, dr_release_t release,
624 dr_match_t match, void *match_data,
625 void (*fn)(struct device *, void *, void *),
627 extern void devres_free(void *res);
628 extern void devres_add(struct device *dev, void *res);
629 extern void *devres_find(struct device *dev, dr_release_t release,
630 dr_match_t match, void *match_data);
631 extern void *devres_get(struct device *dev, void *new_res,
632 dr_match_t match, void *match_data);
633 extern void *devres_remove(struct device *dev, dr_release_t release,
634 dr_match_t match, void *match_data);
635 extern int devres_destroy(struct device *dev, dr_release_t release,
636 dr_match_t match, void *match_data);
637 extern int devres_release(struct device *dev, dr_release_t release,
638 dr_match_t match, void *match_data);
641 extern void * __must_check devres_open_group(struct device *dev, void *id,
643 extern void devres_close_group(struct device *dev, void *id);
644 extern void devres_remove_group(struct device *dev, void *id);
645 extern int devres_release_group(struct device *dev, void *id);
647 /* managed devm_k.alloc/kfree for device drivers */
648 extern void *devm_kmalloc(struct device *dev, size_t size, gfp_t gfp);
649 extern __printf(3, 0)
650 char *devm_kvasprintf(struct device *dev, gfp_t gfp, const char *fmt,
652 extern __printf(3, 4)
653 char *devm_kasprintf(struct device *dev, gfp_t gfp, const char *fmt, ...);
654 static inline void *devm_kzalloc(struct device *dev, size_t size, gfp_t gfp)
656 return devm_kmalloc(dev, size, gfp | __GFP_ZERO);
658 static inline void *devm_kmalloc_array(struct device *dev,
659 size_t n, size_t size, gfp_t flags)
661 if (size != 0 && n > SIZE_MAX / size)
663 return devm_kmalloc(dev, n * size, flags);
665 static inline void *devm_kcalloc(struct device *dev,
666 size_t n, size_t size, gfp_t flags)
668 return devm_kmalloc_array(dev, n, size, flags | __GFP_ZERO);
670 extern void devm_kfree(struct device *dev, void *p);
671 extern char *devm_kstrdup(struct device *dev, const char *s, gfp_t gfp);
672 extern void *devm_kmemdup(struct device *dev, const void *src, size_t len,
675 extern unsigned long devm_get_free_pages(struct device *dev,
676 gfp_t gfp_mask, unsigned int order);
677 extern void devm_free_pages(struct device *dev, unsigned long addr);
679 void __iomem *devm_ioremap_resource(struct device *dev, struct resource *res);
681 /* allows to add/remove a custom action to devres stack */
682 int devm_add_action(struct device *dev, void (*action)(void *), void *data);
683 void devm_remove_action(struct device *dev, void (*action)(void *), void *data);
685 static inline int devm_add_action_or_reset(struct device *dev,
686 void (*action)(void *), void *data)
690 ret = devm_add_action(dev, action, data);
697 struct device_dma_parameters {
699 * a low level driver may set these to teach IOMMU code about
702 unsigned int max_segment_size;
703 unsigned long segment_boundary_mask;
707 * struct device - The basic device structure
708 * @parent: The device's "parent" device, the device to which it is attached.
709 * In most cases, a parent device is some sort of bus or host
710 * controller. If parent is NULL, the device, is a top-level device,
711 * which is not usually what you want.
712 * @p: Holds the private data of the driver core portions of the device.
713 * See the comment of the struct device_private for detail.
714 * @kobj: A top-level, abstract class from which other classes are derived.
715 * @init_name: Initial name of the device.
716 * @type: The type of device.
717 * This identifies the device type and carries type-specific
719 * @mutex: Mutex to synchronize calls to its driver.
720 * @bus: Type of bus device is on.
721 * @driver: Which driver has allocated this
722 * @platform_data: Platform data specific to the device.
723 * Example: For devices on custom boards, as typical of embedded
724 * and SOC based hardware, Linux often uses platform_data to point
725 * to board-specific structures describing devices and how they
726 * are wired. That can include what ports are available, chip
727 * variants, which GPIO pins act in what additional roles, and so
728 * on. This shrinks the "Board Support Packages" (BSPs) and
729 * minimizes board-specific #ifdefs in drivers.
730 * @driver_data: Private pointer for driver specific info.
731 * @power: For device power management.
732 * See Documentation/power/devices.txt for details.
733 * @pm_domain: Provide callbacks that are executed during system suspend,
734 * hibernation, system resume and during runtime PM transitions
735 * along with subsystem-level and driver-level callbacks.
736 * @pins: For device pin management.
737 * See Documentation/pinctrl.txt for details.
738 * @msi_list: Hosts MSI descriptors
739 * @msi_domain: The generic MSI domain this device is using.
740 * @numa_node: NUMA node this device is close to.
741 * @dma_mask: Dma mask (if dma'ble device).
742 * @coherent_dma_mask: Like dma_mask, but for alloc_coherent mapping as not all
743 * hardware supports 64-bit addresses for consistent allocations
745 * @dma_pfn_offset: offset of DMA memory range relatively of RAM
746 * @dma_parms: A low level driver may set these to teach IOMMU code about
747 * segment limitations.
748 * @dma_pools: Dma pools (if dma'ble device).
749 * @dma_mem: Internal for coherent mem override.
750 * @cma_area: Contiguous memory area for dma allocations
751 * @archdata: For arch-specific additions.
752 * @of_node: Associated device tree node.
753 * @fwnode: Associated device node supplied by platform firmware.
754 * @devt: For creating the sysfs "dev".
755 * @id: device instance
756 * @devres_lock: Spinlock to protect the resource of the device.
757 * @devres_head: The resources list of the device.
758 * @knode_class: The node used to add the device to the class list.
759 * @class: The class of the device.
760 * @groups: Optional attribute groups.
761 * @release: Callback to free the device after all references have
762 * gone away. This should be set by the allocator of the
763 * device (i.e. the bus driver that discovered the device).
764 * @iommu_group: IOMMU group the device belongs to.
766 * @offline_disabled: If set, the device is permanently online.
767 * @offline: Set after successful invocation of bus type's .offline().
769 * At the lowest level, every device in a Linux system is represented by an
770 * instance of struct device. The device structure contains the information
771 * that the device model core needs to model the system. Most subsystems,
772 * however, track additional information about the devices they host. As a
773 * result, it is rare for devices to be represented by bare device structures;
774 * instead, that structure, like kobject structures, is usually embedded within
775 * a higher-level representation of the device.
778 struct device *parent;
780 struct device_private *p;
783 const char *init_name; /* initial name of the device */
784 const struct device_type *type;
786 struct mutex mutex; /* mutex to synchronize calls to
790 struct bus_type *bus; /* type of bus device is on */
791 struct device_driver *driver; /* which driver has allocated this
793 void *platform_data; /* Platform specific data, device
794 core doesn't touch it */
795 void *driver_data; /* Driver data, set and get with
796 dev_set/get_drvdata */
797 struct dev_pm_info power;
798 struct dev_pm_domain *pm_domain;
800 #ifdef CONFIG_GENERIC_MSI_IRQ_DOMAIN
801 struct irq_domain *msi_domain;
803 #ifdef CONFIG_PINCTRL
804 struct dev_pin_info *pins;
806 #ifdef CONFIG_GENERIC_MSI_IRQ
807 struct list_head msi_list;
811 int numa_node; /* NUMA node this device is close to */
813 u64 *dma_mask; /* dma mask (if dma'able device) */
814 u64 coherent_dma_mask;/* Like dma_mask, but for
815 alloc_coherent mappings as
816 not all hardware supports
817 64 bit addresses for consistent
818 allocations such descriptors. */
819 unsigned long dma_pfn_offset;
821 struct device_dma_parameters *dma_parms;
823 struct list_head dma_pools; /* dma pools (if dma'ble) */
825 struct dma_coherent_mem *dma_mem; /* internal for coherent mem
827 #ifdef CONFIG_DMA_CMA
828 struct cma *cma_area; /* contiguous memory area for dma
831 /* arch specific additions */
832 struct dev_archdata archdata;
834 struct device_node *of_node; /* associated device tree node */
835 struct fwnode_handle *fwnode; /* firmware device node */
837 dev_t devt; /* dev_t, creates the sysfs "dev" */
838 u32 id; /* device instance */
840 spinlock_t devres_lock;
841 struct list_head devres_head;
843 struct klist_node knode_class;
845 const struct attribute_group **groups; /* optional groups */
847 void (*release)(struct device *dev);
848 struct iommu_group *iommu_group;
850 bool offline_disabled:1;
854 static inline struct device *kobj_to_dev(struct kobject *kobj)
856 return container_of(kobj, struct device, kobj);
859 /* Get the wakeup routines, which depend on struct device */
860 #include <linux/pm_wakeup.h>
862 static inline const char *dev_name(const struct device *dev)
864 /* Use the init name until the kobject becomes available */
866 return dev->init_name;
868 return kobject_name(&dev->kobj);
871 extern __printf(2, 3)
872 int dev_set_name(struct device *dev, const char *name, ...);
875 static inline int dev_to_node(struct device *dev)
877 return dev->numa_node;
879 static inline void set_dev_node(struct device *dev, int node)
881 dev->numa_node = node;
884 static inline int dev_to_node(struct device *dev)
888 static inline void set_dev_node(struct device *dev, int node)
893 static inline struct irq_domain *dev_get_msi_domain(const struct device *dev)
895 #ifdef CONFIG_GENERIC_MSI_IRQ_DOMAIN
896 return dev->msi_domain;
902 static inline void dev_set_msi_domain(struct device *dev, struct irq_domain *d)
904 #ifdef CONFIG_GENERIC_MSI_IRQ_DOMAIN
909 static inline void *dev_get_drvdata(const struct device *dev)
911 return dev->driver_data;
914 static inline void dev_set_drvdata(struct device *dev, void *data)
916 dev->driver_data = data;
919 static inline struct pm_subsys_data *dev_to_psd(struct device *dev)
921 return dev ? dev->power.subsys_data : NULL;
924 static inline unsigned int dev_get_uevent_suppress(const struct device *dev)
926 return dev->kobj.uevent_suppress;
929 static inline void dev_set_uevent_suppress(struct device *dev, int val)
931 dev->kobj.uevent_suppress = val;
934 static inline int device_is_registered(struct device *dev)
936 return dev->kobj.state_in_sysfs;
939 static inline void device_enable_async_suspend(struct device *dev)
941 if (!dev->power.is_prepared)
942 dev->power.async_suspend = true;
945 static inline void device_disable_async_suspend(struct device *dev)
947 if (!dev->power.is_prepared)
948 dev->power.async_suspend = false;
951 static inline bool device_async_suspend_enabled(struct device *dev)
953 return !!dev->power.async_suspend;
956 static inline void pm_suspend_ignore_children(struct device *dev, bool enable)
958 dev->power.ignore_children = enable;
961 static inline void dev_pm_syscore_device(struct device *dev, bool val)
963 #ifdef CONFIG_PM_SLEEP
964 dev->power.syscore = val;
968 static inline void device_lock(struct device *dev)
970 mutex_lock(&dev->mutex);
973 static inline int device_trylock(struct device *dev)
975 return mutex_trylock(&dev->mutex);
978 static inline void device_unlock(struct device *dev)
980 mutex_unlock(&dev->mutex);
983 static inline void device_lock_assert(struct device *dev)
985 lockdep_assert_held(&dev->mutex);
988 static inline struct device_node *dev_of_node(struct device *dev)
990 if (!IS_ENABLED(CONFIG_OF))
995 void driver_init(void);
998 * High level routines for use by the bus drivers
1000 extern int __must_check device_register(struct device *dev);
1001 extern void device_unregister(struct device *dev);
1002 extern void device_initialize(struct device *dev);
1003 extern int __must_check device_add(struct device *dev);
1004 extern void device_del(struct device *dev);
1005 extern int device_for_each_child(struct device *dev, void *data,
1006 int (*fn)(struct device *dev, void *data));
1007 extern int device_for_each_child_reverse(struct device *dev, void *data,
1008 int (*fn)(struct device *dev, void *data));
1009 extern struct device *device_find_child(struct device *dev, void *data,
1010 int (*match)(struct device *dev, void *data));
1011 extern int device_rename(struct device *dev, const char *new_name);
1012 extern int device_move(struct device *dev, struct device *new_parent,
1013 enum dpm_order dpm_order);
1014 extern const char *device_get_devnode(struct device *dev,
1015 umode_t *mode, kuid_t *uid, kgid_t *gid,
1018 static inline bool device_supports_offline(struct device *dev)
1020 return dev->bus && dev->bus->offline && dev->bus->online;
1023 extern void lock_device_hotplug(void);
1024 extern void unlock_device_hotplug(void);
1025 extern int lock_device_hotplug_sysfs(void);
1026 extern int device_offline(struct device *dev);
1027 extern int device_online(struct device *dev);
1028 extern void set_primary_fwnode(struct device *dev, struct fwnode_handle *fwnode);
1029 extern void set_secondary_fwnode(struct device *dev, struct fwnode_handle *fwnode);
1032 * Root device objects for grouping under /sys/devices
1034 extern struct device *__root_device_register(const char *name,
1035 struct module *owner);
1037 /* This is a macro to avoid include problems with THIS_MODULE */
1038 #define root_device_register(name) \
1039 __root_device_register(name, THIS_MODULE)
1041 extern void root_device_unregister(struct device *root);
1043 static inline void *dev_get_platdata(const struct device *dev)
1045 return dev->platform_data;
1049 * Manual binding of a device to driver. See drivers/base/bus.c
1050 * for information on use.
1052 extern int __must_check device_bind_driver(struct device *dev);
1053 extern void device_release_driver(struct device *dev);
1054 extern int __must_check device_attach(struct device *dev);
1055 extern int __must_check driver_attach(struct device_driver *drv);
1056 extern void device_initial_probe(struct device *dev);
1057 extern int __must_check device_reprobe(struct device *dev);
1059 extern bool device_is_bound(struct device *dev);
1062 * Easy functions for dynamically creating devices on the fly
1064 extern __printf(5, 0)
1065 struct device *device_create_vargs(struct class *cls, struct device *parent,
1066 dev_t devt, void *drvdata,
1067 const char *fmt, va_list vargs);
1068 extern __printf(5, 6)
1069 struct device *device_create(struct class *cls, struct device *parent,
1070 dev_t devt, void *drvdata,
1071 const char *fmt, ...);
1072 extern __printf(6, 7)
1073 struct device *device_create_with_groups(struct class *cls,
1074 struct device *parent, dev_t devt, void *drvdata,
1075 const struct attribute_group **groups,
1076 const char *fmt, ...);
1077 extern void device_destroy(struct class *cls, dev_t devt);
1080 * Platform "fixup" functions - allow the platform to have their say
1081 * about devices and actions that the general device layer doesn't
1084 /* Notify platform of device discovery */
1085 extern int (*platform_notify)(struct device *dev);
1087 extern int (*platform_notify_remove)(struct device *dev);
1091 * get_device - atomically increment the reference count for the device.
1094 extern struct device *get_device(struct device *dev);
1095 extern void put_device(struct device *dev);
1097 #ifdef CONFIG_DEVTMPFS
1098 extern int devtmpfs_create_node(struct device *dev);
1099 extern int devtmpfs_delete_node(struct device *dev);
1100 extern int devtmpfs_mount(const char *mntdir);
1102 static inline int devtmpfs_create_node(struct device *dev) { return 0; }
1103 static inline int devtmpfs_delete_node(struct device *dev) { return 0; }
1104 static inline int devtmpfs_mount(const char *mountpoint) { return 0; }
1107 /* drivers/base/power/shutdown.c */
1108 extern void device_shutdown(void);
1110 /* debugging and troubleshooting/diagnostic helpers. */
1111 extern const char *dev_driver_string(const struct device *dev);
1114 #ifdef CONFIG_PRINTK
1116 extern __printf(3, 0)
1117 int dev_vprintk_emit(int level, const struct device *dev,
1118 const char *fmt, va_list args);
1119 extern __printf(3, 4)
1120 int dev_printk_emit(int level, const struct device *dev, const char *fmt, ...);
1122 extern __printf(3, 4)
1123 void dev_printk(const char *level, const struct device *dev,
1124 const char *fmt, ...);
1125 extern __printf(2, 3)
1126 void dev_emerg(const struct device *dev, const char *fmt, ...);
1127 extern __printf(2, 3)
1128 void dev_alert(const struct device *dev, const char *fmt, ...);
1129 extern __printf(2, 3)
1130 void dev_crit(const struct device *dev, const char *fmt, ...);
1131 extern __printf(2, 3)
1132 void dev_err(const struct device *dev, const char *fmt, ...);
1133 extern __printf(2, 3)
1134 void dev_warn(const struct device *dev, const char *fmt, ...);
1135 extern __printf(2, 3)
1136 void dev_notice(const struct device *dev, const char *fmt, ...);
1137 extern __printf(2, 3)
1138 void _dev_info(const struct device *dev, const char *fmt, ...);
1142 static inline __printf(3, 0)
1143 int dev_vprintk_emit(int level, const struct device *dev,
1144 const char *fmt, va_list args)
1146 static inline __printf(3, 4)
1147 int dev_printk_emit(int level, const struct device *dev, const char *fmt, ...)
1150 static inline void __dev_printk(const char *level, const struct device *dev,
1151 struct va_format *vaf)
1153 static inline __printf(3, 4)
1154 void dev_printk(const char *level, const struct device *dev,
1155 const char *fmt, ...)
1158 static inline __printf(2, 3)
1159 void dev_emerg(const struct device *dev, const char *fmt, ...)
1161 static inline __printf(2, 3)
1162 void dev_crit(const struct device *dev, const char *fmt, ...)
1164 static inline __printf(2, 3)
1165 void dev_alert(const struct device *dev, const char *fmt, ...)
1167 static inline __printf(2, 3)
1168 void dev_err(const struct device *dev, const char *fmt, ...)
1170 static inline __printf(2, 3)
1171 void dev_warn(const struct device *dev, const char *fmt, ...)
1173 static inline __printf(2, 3)
1174 void dev_notice(const struct device *dev, const char *fmt, ...)
1176 static inline __printf(2, 3)
1177 void _dev_info(const struct device *dev, const char *fmt, ...)
1183 * Stupid hackaround for existing uses of non-printk uses dev_info
1185 * Note that the definition of dev_info below is actually _dev_info
1186 * and a macro is used to avoid redefining dev_info
1189 #define dev_info(dev, fmt, arg...) _dev_info(dev, fmt, ##arg)
1191 #if defined(CONFIG_DYNAMIC_DEBUG)
1192 #define dev_dbg(dev, format, ...) \
1194 dynamic_dev_dbg(dev, format, ##__VA_ARGS__); \
1196 #elif defined(DEBUG)
1197 #define dev_dbg(dev, format, arg...) \
1198 dev_printk(KERN_DEBUG, dev, format, ##arg)
1200 #define dev_dbg(dev, format, arg...) \
1203 dev_printk(KERN_DEBUG, dev, format, ##arg); \
1207 #ifdef CONFIG_PRINTK
1208 #define dev_level_once(dev_level, dev, fmt, ...) \
1210 static bool __print_once __read_mostly; \
1212 if (!__print_once) { \
1213 __print_once = true; \
1214 dev_level(dev, fmt, ##__VA_ARGS__); \
1218 #define dev_level_once(dev_level, dev, fmt, ...) \
1221 dev_level(dev, fmt, ##__VA_ARGS__); \
1225 #define dev_emerg_once(dev, fmt, ...) \
1226 dev_level_once(dev_emerg, dev, fmt, ##__VA_ARGS__)
1227 #define dev_alert_once(dev, fmt, ...) \
1228 dev_level_once(dev_alert, dev, fmt, ##__VA_ARGS__)
1229 #define dev_crit_once(dev, fmt, ...) \
1230 dev_level_once(dev_crit, dev, fmt, ##__VA_ARGS__)
1231 #define dev_err_once(dev, fmt, ...) \
1232 dev_level_once(dev_err, dev, fmt, ##__VA_ARGS__)
1233 #define dev_warn_once(dev, fmt, ...) \
1234 dev_level_once(dev_warn, dev, fmt, ##__VA_ARGS__)
1235 #define dev_notice_once(dev, fmt, ...) \
1236 dev_level_once(dev_notice, dev, fmt, ##__VA_ARGS__)
1237 #define dev_info_once(dev, fmt, ...) \
1238 dev_level_once(dev_info, dev, fmt, ##__VA_ARGS__)
1239 #define dev_dbg_once(dev, fmt, ...) \
1240 dev_level_once(dev_dbg, dev, fmt, ##__VA_ARGS__)
1242 #define dev_level_ratelimited(dev_level, dev, fmt, ...) \
1244 static DEFINE_RATELIMIT_STATE(_rs, \
1245 DEFAULT_RATELIMIT_INTERVAL, \
1246 DEFAULT_RATELIMIT_BURST); \
1247 if (__ratelimit(&_rs)) \
1248 dev_level(dev, fmt, ##__VA_ARGS__); \
1251 #define dev_emerg_ratelimited(dev, fmt, ...) \
1252 dev_level_ratelimited(dev_emerg, dev, fmt, ##__VA_ARGS__)
1253 #define dev_alert_ratelimited(dev, fmt, ...) \
1254 dev_level_ratelimited(dev_alert, dev, fmt, ##__VA_ARGS__)
1255 #define dev_crit_ratelimited(dev, fmt, ...) \
1256 dev_level_ratelimited(dev_crit, dev, fmt, ##__VA_ARGS__)
1257 #define dev_err_ratelimited(dev, fmt, ...) \
1258 dev_level_ratelimited(dev_err, dev, fmt, ##__VA_ARGS__)
1259 #define dev_warn_ratelimited(dev, fmt, ...) \
1260 dev_level_ratelimited(dev_warn, dev, fmt, ##__VA_ARGS__)
1261 #define dev_notice_ratelimited(dev, fmt, ...) \
1262 dev_level_ratelimited(dev_notice, dev, fmt, ##__VA_ARGS__)
1263 #define dev_info_ratelimited(dev, fmt, ...) \
1264 dev_level_ratelimited(dev_info, dev, fmt, ##__VA_ARGS__)
1265 #if defined(CONFIG_DYNAMIC_DEBUG)
1266 /* descriptor check is first to prevent flooding with "callbacks suppressed" */
1267 #define dev_dbg_ratelimited(dev, fmt, ...) \
1269 static DEFINE_RATELIMIT_STATE(_rs, \
1270 DEFAULT_RATELIMIT_INTERVAL, \
1271 DEFAULT_RATELIMIT_BURST); \
1272 DEFINE_DYNAMIC_DEBUG_METADATA(descriptor, fmt); \
1273 if (unlikely(descriptor.flags & _DPRINTK_FLAGS_PRINT) && \
1274 __ratelimit(&_rs)) \
1275 __dynamic_dev_dbg(&descriptor, dev, fmt, \
1278 #elif defined(DEBUG)
1279 #define dev_dbg_ratelimited(dev, fmt, ...) \
1281 static DEFINE_RATELIMIT_STATE(_rs, \
1282 DEFAULT_RATELIMIT_INTERVAL, \
1283 DEFAULT_RATELIMIT_BURST); \
1284 if (__ratelimit(&_rs)) \
1285 dev_printk(KERN_DEBUG, dev, fmt, ##__VA_ARGS__); \
1288 #define dev_dbg_ratelimited(dev, fmt, ...) \
1289 no_printk(KERN_DEBUG pr_fmt(fmt), ##__VA_ARGS__)
1292 #ifdef VERBOSE_DEBUG
1293 #define dev_vdbg dev_dbg
1295 #define dev_vdbg(dev, format, arg...) \
1298 dev_printk(KERN_DEBUG, dev, format, ##arg); \
1303 * dev_WARN*() acts like dev_printk(), but with the key difference of
1304 * using WARN/WARN_ONCE to include file/line information and a backtrace.
1306 #define dev_WARN(dev, format, arg...) \
1307 WARN(1, "%s %s: " format, dev_driver_string(dev), dev_name(dev), ## arg);
1309 #define dev_WARN_ONCE(dev, condition, format, arg...) \
1310 WARN_ONCE(condition, "%s %s: " format, \
1311 dev_driver_string(dev), dev_name(dev), ## arg)
1313 /* Create alias, so I can be autoloaded. */
1314 #define MODULE_ALIAS_CHARDEV(major,minor) \
1315 MODULE_ALIAS("char-major-" __stringify(major) "-" __stringify(minor))
1316 #define MODULE_ALIAS_CHARDEV_MAJOR(major) \
1317 MODULE_ALIAS("char-major-" __stringify(major) "-*")
1319 #ifdef CONFIG_SYSFS_DEPRECATED
1320 extern long sysfs_deprecated;
1322 #define sysfs_deprecated 0
1326 * module_driver() - Helper macro for drivers that don't do anything
1327 * special in module init/exit. This eliminates a lot of boilerplate.
1328 * Each module may only use this macro once, and calling it replaces
1329 * module_init() and module_exit().
1331 * @__driver: driver name
1332 * @__register: register function for this driver type
1333 * @__unregister: unregister function for this driver type
1334 * @...: Additional arguments to be passed to __register and __unregister.
1336 * Use this macro to construct bus specific macros for registering
1337 * drivers, and do not use it on its own.
1339 #define module_driver(__driver, __register, __unregister, ...) \
1340 static int __init __driver##_init(void) \
1342 return __register(&(__driver) , ##__VA_ARGS__); \
1344 module_init(__driver##_init); \
1345 static void __exit __driver##_exit(void) \
1347 __unregister(&(__driver) , ##__VA_ARGS__); \
1349 module_exit(__driver##_exit);
1352 * builtin_driver() - Helper macro for drivers that don't do anything
1353 * special in init and have no exit. This eliminates some boilerplate.
1354 * Each driver may only use this macro once, and calling it replaces
1355 * device_initcall (or in some cases, the legacy __initcall). This is
1356 * meant to be a direct parallel of module_driver() above but without
1357 * the __exit stuff that is not used for builtin cases.
1359 * @__driver: driver name
1360 * @__register: register function for this driver type
1361 * @...: Additional arguments to be passed to __register
1363 * Use this macro to construct bus specific macros for registering
1364 * drivers, and do not use it on its own.
1366 #define builtin_driver(__driver, __register, ...) \
1367 static int __init __driver##_init(void) \
1369 return __register(&(__driver) , ##__VA_ARGS__); \
1371 device_initcall(__driver##_init);
1373 #endif /* _DEVICE_H_ */