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: Used by drivers that work equally well
205 * whether probed synchronously or asynchronously.
206 * @PROBE_PREFER_ASYNCHRONOUS: Drivers for "slow" devices which
207 * probing order is not essential for booting the system may
208 * opt into executing their probes asynchronously.
209 * @PROBE_FORCE_SYNCHRONOUS: Use this to annotate drivers that need
210 * their probe routines to run synchronously with driver and
211 * device registration (with the exception of -EPROBE_DEFER
212 * handling - re-probing always ends up being done 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,
223 PROBE_FORCE_SYNCHRONOUS,
227 * struct device_driver - The basic device driver structure
228 * @name: Name of the device driver.
229 * @bus: The bus which the device of this driver belongs to.
230 * @owner: The module owner.
231 * @mod_name: Used for built-in modules.
232 * @suppress_bind_attrs: Disables bind/unbind via sysfs.
233 * @probe_type: Type of the probe (synchronous or asynchronous) to use.
234 * @of_match_table: The open firmware table.
235 * @acpi_match_table: The ACPI match table.
236 * @probe: Called to query the existence of a specific device,
237 * whether this driver can work with it, and bind the driver
238 * to a specific device.
239 * @remove: Called when the device is removed from the system to
240 * unbind a device from this driver.
241 * @shutdown: Called at shut-down time to quiesce the device.
242 * @suspend: Called to put the device to sleep mode. Usually to a
244 * @resume: Called to bring a device from sleep mode.
245 * @groups: Default attributes that get created by the driver core
247 * @pm: Power management operations of the device which matched
249 * @p: Driver core's private data, no one other than the driver
250 * core can touch this.
252 * The device driver-model tracks all of the drivers known to the system.
253 * The main reason for this tracking is to enable the driver core to match
254 * up drivers with new devices. Once drivers are known objects within the
255 * system, however, a number of other things become possible. Device drivers
256 * can export information and configuration variables that are independent
257 * of any specific device.
259 struct device_driver {
261 struct bus_type *bus;
263 struct module *owner;
264 const char *mod_name; /* used for built-in modules */
266 bool suppress_bind_attrs; /* disables bind/unbind via sysfs */
267 enum probe_type probe_type;
269 const struct of_device_id *of_match_table;
270 const struct acpi_device_id *acpi_match_table;
272 int (*probe) (struct device *dev);
273 int (*remove) (struct device *dev);
274 void (*shutdown) (struct device *dev);
275 int (*suspend) (struct device *dev, pm_message_t state);
276 int (*resume) (struct device *dev);
277 const struct attribute_group **groups;
279 const struct dev_pm_ops *pm;
281 struct driver_private *p;
285 extern int __must_check driver_register(struct device_driver *drv);
286 extern void driver_unregister(struct device_driver *drv);
288 extern struct device_driver *driver_find(const char *name,
289 struct bus_type *bus);
290 extern int driver_probe_done(void);
291 extern void wait_for_device_probe(void);
294 /* sysfs interface for exporting driver attributes */
296 struct driver_attribute {
297 struct attribute attr;
298 ssize_t (*show)(struct device_driver *driver, char *buf);
299 ssize_t (*store)(struct device_driver *driver, const char *buf,
303 #define DRIVER_ATTR(_name, _mode, _show, _store) \
304 struct driver_attribute driver_attr_##_name = __ATTR(_name, _mode, _show, _store)
305 #define DRIVER_ATTR_RW(_name) \
306 struct driver_attribute driver_attr_##_name = __ATTR_RW(_name)
307 #define DRIVER_ATTR_RO(_name) \
308 struct driver_attribute driver_attr_##_name = __ATTR_RO(_name)
309 #define DRIVER_ATTR_WO(_name) \
310 struct driver_attribute driver_attr_##_name = __ATTR_WO(_name)
312 extern int __must_check driver_create_file(struct device_driver *driver,
313 const struct driver_attribute *attr);
314 extern void driver_remove_file(struct device_driver *driver,
315 const struct driver_attribute *attr);
317 extern int __must_check driver_for_each_device(struct device_driver *drv,
318 struct device *start,
320 int (*fn)(struct device *dev,
322 struct device *driver_find_device(struct device_driver *drv,
323 struct device *start, void *data,
324 int (*match)(struct device *dev, void *data));
327 * struct subsys_interface - interfaces to device functions
328 * @name: name of the device function
329 * @subsys: subsytem of the devices to attach to
330 * @node: the list of functions registered at the subsystem
331 * @add_dev: device hookup to device function handler
332 * @remove_dev: device hookup to device function handler
334 * Simple interfaces attached to a subsystem. Multiple interfaces can
335 * attach to a subsystem and its devices. Unlike drivers, they do not
336 * exclusively claim or control devices. Interfaces usually represent
337 * a specific functionality of a subsystem/class of devices.
339 struct subsys_interface {
341 struct bus_type *subsys;
342 struct list_head node;
343 int (*add_dev)(struct device *dev, struct subsys_interface *sif);
344 void (*remove_dev)(struct device *dev, struct subsys_interface *sif);
347 int subsys_interface_register(struct subsys_interface *sif);
348 void subsys_interface_unregister(struct subsys_interface *sif);
350 int subsys_system_register(struct bus_type *subsys,
351 const struct attribute_group **groups);
352 int subsys_virtual_register(struct bus_type *subsys,
353 const struct attribute_group **groups);
356 * struct class - device classes
357 * @name: Name of the class.
358 * @owner: The module owner.
359 * @class_attrs: Default attributes of this class.
360 * @dev_groups: Default attributes of the devices that belong to the class.
361 * @dev_kobj: The kobject that represents this class and links it into the hierarchy.
362 * @dev_uevent: Called when a device is added, removed from this class, or a
363 * few other things that generate uevents to add the environment
365 * @devnode: Callback to provide the devtmpfs.
366 * @class_release: Called to release this class.
367 * @dev_release: Called to release the device.
368 * @suspend: Used to put the device to sleep mode, usually to a low power
370 * @resume: Used to bring the device from the sleep mode.
371 * @shutdown: Called at shut-down time to quiesce the device.
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);
400 int (*shutdown)(struct device *dev);
402 const struct kobj_ns_type_operations *ns_type;
403 const void *(*namespace)(struct device *dev);
405 const struct dev_pm_ops *pm;
407 struct subsys_private *p;
410 struct class_dev_iter {
411 struct klist_iter ki;
412 const struct device_type *type;
415 extern struct kobject *sysfs_dev_block_kobj;
416 extern struct kobject *sysfs_dev_char_kobj;
417 extern int __must_check __class_register(struct class *class,
418 struct lock_class_key *key);
419 extern void class_unregister(struct class *class);
421 /* This is a #define to keep the compiler from merging different
422 * instances of the __key variable */
423 #define class_register(class) \
425 static struct lock_class_key __key; \
426 __class_register(class, &__key); \
430 struct class_compat *class_compat_register(const char *name);
431 void class_compat_unregister(struct class_compat *cls);
432 int class_compat_create_link(struct class_compat *cls, struct device *dev,
433 struct device *device_link);
434 void class_compat_remove_link(struct class_compat *cls, struct device *dev,
435 struct device *device_link);
437 extern void class_dev_iter_init(struct class_dev_iter *iter,
439 struct device *start,
440 const struct device_type *type);
441 extern struct device *class_dev_iter_next(struct class_dev_iter *iter);
442 extern void class_dev_iter_exit(struct class_dev_iter *iter);
444 extern int class_for_each_device(struct class *class, struct device *start,
446 int (*fn)(struct device *dev, void *data));
447 extern struct device *class_find_device(struct class *class,
448 struct device *start, const void *data,
449 int (*match)(struct device *, const void *));
451 struct class_attribute {
452 struct attribute attr;
453 ssize_t (*show)(struct class *class, struct class_attribute *attr,
455 ssize_t (*store)(struct class *class, struct class_attribute *attr,
456 const char *buf, size_t count);
459 #define CLASS_ATTR(_name, _mode, _show, _store) \
460 struct class_attribute class_attr_##_name = __ATTR(_name, _mode, _show, _store)
461 #define CLASS_ATTR_RW(_name) \
462 struct class_attribute class_attr_##_name = __ATTR_RW(_name)
463 #define CLASS_ATTR_RO(_name) \
464 struct class_attribute class_attr_##_name = __ATTR_RO(_name)
466 extern int __must_check class_create_file_ns(struct class *class,
467 const struct class_attribute *attr,
469 extern void class_remove_file_ns(struct class *class,
470 const struct class_attribute *attr,
473 static inline int __must_check class_create_file(struct class *class,
474 const struct class_attribute *attr)
476 return class_create_file_ns(class, attr, NULL);
479 static inline void class_remove_file(struct class *class,
480 const struct class_attribute *attr)
482 return class_remove_file_ns(class, attr, NULL);
485 /* Simple class attribute that is just a static string */
486 struct class_attribute_string {
487 struct class_attribute attr;
491 /* Currently read-only only */
492 #define _CLASS_ATTR_STRING(_name, _mode, _str) \
493 { __ATTR(_name, _mode, show_class_attr_string, NULL), _str }
494 #define CLASS_ATTR_STRING(_name, _mode, _str) \
495 struct class_attribute_string class_attr_##_name = \
496 _CLASS_ATTR_STRING(_name, _mode, _str)
498 extern ssize_t show_class_attr_string(struct class *class, struct class_attribute *attr,
501 struct class_interface {
502 struct list_head node;
505 int (*add_dev) (struct device *, struct class_interface *);
506 void (*remove_dev) (struct device *, struct class_interface *);
509 extern int __must_check class_interface_register(struct class_interface *);
510 extern void class_interface_unregister(struct class_interface *);
512 extern struct class * __must_check __class_create(struct module *owner,
514 struct lock_class_key *key);
515 extern void class_destroy(struct class *cls);
517 /* This is a #define to keep the compiler from merging different
518 * instances of the __key variable */
519 #define class_create(owner, name) \
521 static struct lock_class_key __key; \
522 __class_create(owner, name, &__key); \
526 * The type of device, "struct device" is embedded in. A class
527 * or bus can contain devices of different types
528 * like "partitions" and "disks", "mouse" and "event".
529 * This identifies the device type and carries type-specific
530 * information, equivalent to the kobj_type of a kobject.
531 * If "name" is specified, the uevent will contain it in
532 * the DEVTYPE variable.
536 const struct attribute_group **groups;
537 int (*uevent)(struct device *dev, struct kobj_uevent_env *env);
538 char *(*devnode)(struct device *dev, umode_t *mode,
539 kuid_t *uid, kgid_t *gid);
540 void (*release)(struct device *dev);
542 const struct dev_pm_ops *pm;
545 /* interface for exporting device attributes */
546 struct device_attribute {
547 struct attribute attr;
548 ssize_t (*show)(struct device *dev, struct device_attribute *attr,
550 ssize_t (*store)(struct device *dev, struct device_attribute *attr,
551 const char *buf, size_t count);
554 struct dev_ext_attribute {
555 struct device_attribute attr;
559 ssize_t device_show_ulong(struct device *dev, struct device_attribute *attr,
561 ssize_t device_store_ulong(struct device *dev, struct device_attribute *attr,
562 const char *buf, size_t count);
563 ssize_t device_show_int(struct device *dev, struct device_attribute *attr,
565 ssize_t device_store_int(struct device *dev, struct device_attribute *attr,
566 const char *buf, size_t count);
567 ssize_t device_show_bool(struct device *dev, struct device_attribute *attr,
569 ssize_t device_store_bool(struct device *dev, struct device_attribute *attr,
570 const char *buf, size_t count);
572 #define DEVICE_ATTR(_name, _mode, _show, _store) \
573 struct device_attribute dev_attr_##_name = __ATTR(_name, _mode, _show, _store)
574 #define DEVICE_ATTR_RW(_name) \
575 struct device_attribute dev_attr_##_name = __ATTR_RW(_name)
576 #define DEVICE_ATTR_RO(_name) \
577 struct device_attribute dev_attr_##_name = __ATTR_RO(_name)
578 #define DEVICE_ATTR_WO(_name) \
579 struct device_attribute dev_attr_##_name = __ATTR_WO(_name)
580 #define DEVICE_ULONG_ATTR(_name, _mode, _var) \
581 struct dev_ext_attribute dev_attr_##_name = \
582 { __ATTR(_name, _mode, device_show_ulong, device_store_ulong), &(_var) }
583 #define DEVICE_INT_ATTR(_name, _mode, _var) \
584 struct dev_ext_attribute dev_attr_##_name = \
585 { __ATTR(_name, _mode, device_show_int, device_store_int), &(_var) }
586 #define DEVICE_BOOL_ATTR(_name, _mode, _var) \
587 struct dev_ext_attribute dev_attr_##_name = \
588 { __ATTR(_name, _mode, device_show_bool, device_store_bool), &(_var) }
589 #define DEVICE_ATTR_IGNORE_LOCKDEP(_name, _mode, _show, _store) \
590 struct device_attribute dev_attr_##_name = \
591 __ATTR_IGNORE_LOCKDEP(_name, _mode, _show, _store)
593 extern int device_create_file(struct device *device,
594 const struct device_attribute *entry);
595 extern void device_remove_file(struct device *dev,
596 const struct device_attribute *attr);
597 extern bool device_remove_file_self(struct device *dev,
598 const struct device_attribute *attr);
599 extern int __must_check device_create_bin_file(struct device *dev,
600 const struct bin_attribute *attr);
601 extern void device_remove_bin_file(struct device *dev,
602 const struct bin_attribute *attr);
604 /* device resource management */
605 typedef void (*dr_release_t)(struct device *dev, void *res);
606 typedef int (*dr_match_t)(struct device *dev, void *res, void *match_data);
608 #ifdef CONFIG_DEBUG_DEVRES
609 extern void *__devres_alloc_node(dr_release_t release, size_t size, gfp_t gfp,
610 int nid, const char *name);
611 #define devres_alloc(release, size, gfp) \
612 __devres_alloc_node(release, size, gfp, NUMA_NO_NODE, #release)
613 #define devres_alloc_node(release, size, gfp, nid) \
614 __devres_alloc_node(release, size, gfp, nid, #release)
616 extern void *devres_alloc_node(dr_release_t release, size_t size, gfp_t gfp,
618 static inline void *devres_alloc(dr_release_t release, size_t size, gfp_t gfp)
620 return devres_alloc_node(release, size, gfp, NUMA_NO_NODE);
624 extern void devres_for_each_res(struct device *dev, dr_release_t release,
625 dr_match_t match, void *match_data,
626 void (*fn)(struct device *, void *, void *),
628 extern void devres_free(void *res);
629 extern void devres_add(struct device *dev, void *res);
630 extern void *devres_find(struct device *dev, dr_release_t release,
631 dr_match_t match, void *match_data);
632 extern void *devres_get(struct device *dev, void *new_res,
633 dr_match_t match, void *match_data);
634 extern void *devres_remove(struct device *dev, dr_release_t release,
635 dr_match_t match, void *match_data);
636 extern int devres_destroy(struct device *dev, dr_release_t release,
637 dr_match_t match, void *match_data);
638 extern int devres_release(struct device *dev, dr_release_t release,
639 dr_match_t match, void *match_data);
642 extern void * __must_check devres_open_group(struct device *dev, void *id,
644 extern void devres_close_group(struct device *dev, void *id);
645 extern void devres_remove_group(struct device *dev, void *id);
646 extern int devres_release_group(struct device *dev, void *id);
648 /* managed devm_k.alloc/kfree for device drivers */
649 extern void *devm_kmalloc(struct device *dev, size_t size, gfp_t gfp);
650 extern __printf(3, 0)
651 char *devm_kvasprintf(struct device *dev, gfp_t gfp, const char *fmt,
653 extern __printf(3, 4)
654 char *devm_kasprintf(struct device *dev, gfp_t gfp, const char *fmt, ...);
655 static inline void *devm_kzalloc(struct device *dev, size_t size, gfp_t gfp)
657 return devm_kmalloc(dev, size, gfp | __GFP_ZERO);
659 static inline void *devm_kmalloc_array(struct device *dev,
660 size_t n, size_t size, gfp_t flags)
662 if (size != 0 && n > SIZE_MAX / size)
664 return devm_kmalloc(dev, n * size, flags);
666 static inline void *devm_kcalloc(struct device *dev,
667 size_t n, size_t size, gfp_t flags)
669 return devm_kmalloc_array(dev, n, size, flags | __GFP_ZERO);
671 extern void devm_kfree(struct device *dev, void *p);
672 extern char *devm_kstrdup(struct device *dev, const char *s, gfp_t gfp);
673 extern void *devm_kmemdup(struct device *dev, const void *src, size_t len,
676 extern unsigned long devm_get_free_pages(struct device *dev,
677 gfp_t gfp_mask, unsigned int order);
678 extern void devm_free_pages(struct device *dev, unsigned long addr);
680 void __iomem *devm_ioremap_resource(struct device *dev,
681 const struct resource *res);
683 /* allows to add/remove a custom action to devres stack */
684 int devm_add_action(struct device *dev, void (*action)(void *), void *data);
685 void devm_remove_action(struct device *dev, void (*action)(void *), void *data);
687 struct device_dma_parameters {
689 * a low level driver may set these to teach IOMMU code about
692 unsigned int max_segment_size;
693 unsigned long segment_boundary_mask;
697 * struct device - The basic device structure
698 * @parent: The device's "parent" device, the device to which it is attached.
699 * In most cases, a parent device is some sort of bus or host
700 * controller. If parent is NULL, the device, is a top-level device,
701 * which is not usually what you want.
702 * @p: Holds the private data of the driver core portions of the device.
703 * See the comment of the struct device_private for detail.
704 * @kobj: A top-level, abstract class from which other classes are derived.
705 * @init_name: Initial name of the device.
706 * @type: The type of device.
707 * This identifies the device type and carries type-specific
709 * @mutex: Mutex to synchronize calls to its driver.
710 * @bus: Type of bus device is on.
711 * @driver: Which driver has allocated this
712 * @platform_data: Platform data specific to the device.
713 * Example: For devices on custom boards, as typical of embedded
714 * and SOC based hardware, Linux often uses platform_data to point
715 * to board-specific structures describing devices and how they
716 * are wired. That can include what ports are available, chip
717 * variants, which GPIO pins act in what additional roles, and so
718 * on. This shrinks the "Board Support Packages" (BSPs) and
719 * minimizes board-specific #ifdefs in drivers.
720 * @driver_data: Private pointer for driver specific info.
721 * @power: For device power management.
722 * See Documentation/power/devices.txt for details.
723 * @pm_domain: Provide callbacks that are executed during system suspend,
724 * hibernation, system resume and during runtime PM transitions
725 * along with subsystem-level and driver-level callbacks.
726 * @pins: For device pin management.
727 * See Documentation/pinctrl.txt for details.
728 * @msi_list: Hosts MSI descriptors
729 * @msi_domain: The generic MSI domain this device is using.
730 * @numa_node: NUMA node this device is close to.
731 * @dma_mask: Dma mask (if dma'ble device).
732 * @coherent_dma_mask: Like dma_mask, but for alloc_coherent mapping as not all
733 * hardware supports 64-bit addresses for consistent allocations
735 * @dma_pfn_offset: offset of DMA memory range relatively of RAM
736 * @dma_parms: A low level driver may set these to teach IOMMU code about
737 * segment limitations.
738 * @dma_pools: Dma pools (if dma'ble device).
739 * @dma_mem: Internal for coherent mem override.
740 * @cma_area: Contiguous memory area for dma allocations
741 * @archdata: For arch-specific additions.
742 * @of_node: Associated device tree node.
743 * @fwnode: Associated device node supplied by platform firmware.
744 * @devt: For creating the sysfs "dev".
745 * @id: device instance
746 * @devres_lock: Spinlock to protect the resource of the device.
747 * @devres_head: The resources list of the device.
748 * @knode_class: The node used to add the device to the class list.
749 * @class: The class of the device.
750 * @groups: Optional attribute groups.
751 * @release: Callback to free the device after all references have
752 * gone away. This should be set by the allocator of the
753 * device (i.e. the bus driver that discovered the device).
754 * @iommu_group: IOMMU group the device belongs to.
756 * @offline_disabled: If set, the device is permanently online.
757 * @offline: Set after successful invocation of bus type's .offline().
759 * At the lowest level, every device in a Linux system is represented by an
760 * instance of struct device. The device structure contains the information
761 * that the device model core needs to model the system. Most subsystems,
762 * however, track additional information about the devices they host. As a
763 * result, it is rare for devices to be represented by bare device structures;
764 * instead, that structure, like kobject structures, is usually embedded within
765 * a higher-level representation of the device.
768 struct device *parent;
770 struct device_private *p;
773 const char *init_name; /* initial name of the device */
774 const struct device_type *type;
776 struct mutex mutex; /* mutex to synchronize calls to
780 struct bus_type *bus; /* type of bus device is on */
781 struct device_driver *driver; /* which driver has allocated this
783 void *platform_data; /* Platform specific data, device
784 core doesn't touch it */
785 void *driver_data; /* Driver data, set and get with
786 dev_set/get_drvdata */
787 struct dev_pm_info power;
788 struct dev_pm_domain *pm_domain;
790 #ifdef CONFIG_GENERIC_MSI_IRQ_DOMAIN
791 struct irq_domain *msi_domain;
793 #ifdef CONFIG_PINCTRL
794 struct dev_pin_info *pins;
796 #ifdef CONFIG_GENERIC_MSI_IRQ
797 raw_spinlock_t msi_lock;
798 struct list_head msi_list;
802 int numa_node; /* NUMA node this device is close to */
804 u64 *dma_mask; /* dma mask (if dma'able device) */
805 u64 coherent_dma_mask;/* Like dma_mask, but for
806 alloc_coherent mappings as
807 not all hardware supports
808 64 bit addresses for consistent
809 allocations such descriptors. */
810 unsigned long dma_pfn_offset;
812 struct device_dma_parameters *dma_parms;
814 struct list_head dma_pools; /* dma pools (if dma'ble) */
816 struct dma_coherent_mem *dma_mem; /* internal for coherent mem
818 #ifdef CONFIG_DMA_CMA
819 struct cma *cma_area; /* contiguous memory area for dma
822 /* arch specific additions */
823 struct dev_archdata archdata;
825 struct device_node *of_node; /* associated device tree node */
826 struct fwnode_handle *fwnode; /* firmware device node */
828 dev_t devt; /* dev_t, creates the sysfs "dev" */
829 u32 id; /* device instance */
831 spinlock_t devres_lock;
832 struct list_head devres_head;
834 struct klist_node knode_class;
836 const struct attribute_group **groups; /* optional groups */
838 void (*release)(struct device *dev);
839 struct iommu_group *iommu_group;
841 bool offline_disabled:1;
845 static inline struct device *kobj_to_dev(struct kobject *kobj)
847 return container_of(kobj, struct device, kobj);
850 /* Get the wakeup routines, which depend on struct device */
851 #include <linux/pm_wakeup.h>
853 static inline const char *dev_name(const struct device *dev)
855 /* Use the init name until the kobject becomes available */
857 return dev->init_name;
859 return kobject_name(&dev->kobj);
862 extern __printf(2, 3)
863 int dev_set_name(struct device *dev, const char *name, ...);
866 static inline int dev_to_node(struct device *dev)
868 return dev->numa_node;
870 static inline void set_dev_node(struct device *dev, int node)
872 dev->numa_node = node;
875 static inline int dev_to_node(struct device *dev)
879 static inline void set_dev_node(struct device *dev, int node)
884 static inline struct irq_domain *dev_get_msi_domain(const struct device *dev)
886 #ifdef CONFIG_GENERIC_MSI_IRQ_DOMAIN
887 return dev->msi_domain;
893 static inline void dev_set_msi_domain(struct device *dev, struct irq_domain *d)
895 #ifdef CONFIG_GENERIC_MSI_IRQ_DOMAIN
900 static inline void *dev_get_drvdata(const struct device *dev)
902 return dev->driver_data;
905 static inline void dev_set_drvdata(struct device *dev, void *data)
907 dev->driver_data = data;
910 static inline struct pm_subsys_data *dev_to_psd(struct device *dev)
912 return dev ? dev->power.subsys_data : NULL;
915 static inline unsigned int dev_get_uevent_suppress(const struct device *dev)
917 return dev->kobj.uevent_suppress;
920 static inline void dev_set_uevent_suppress(struct device *dev, int val)
922 dev->kobj.uevent_suppress = val;
925 static inline int device_is_registered(struct device *dev)
927 return dev->kobj.state_in_sysfs;
930 static inline void device_enable_async_suspend(struct device *dev)
932 if (!dev->power.is_prepared)
933 dev->power.async_suspend = true;
936 static inline void device_disable_async_suspend(struct device *dev)
938 if (!dev->power.is_prepared)
939 dev->power.async_suspend = false;
942 static inline bool device_async_suspend_enabled(struct device *dev)
944 return !!dev->power.async_suspend;
947 static inline void pm_suspend_ignore_children(struct device *dev, bool enable)
949 dev->power.ignore_children = enable;
952 static inline void dev_pm_syscore_device(struct device *dev, bool val)
954 #ifdef CONFIG_PM_SLEEP
955 dev->power.syscore = val;
959 static inline void device_lock(struct device *dev)
961 mutex_lock(&dev->mutex);
964 static inline int device_trylock(struct device *dev)
966 return mutex_trylock(&dev->mutex);
969 static inline void device_unlock(struct device *dev)
971 mutex_unlock(&dev->mutex);
974 static inline void device_lock_assert(struct device *dev)
976 lockdep_assert_held(&dev->mutex);
979 static inline struct device_node *dev_of_node(struct device *dev)
981 if (!IS_ENABLED(CONFIG_OF))
986 void driver_init(void);
989 * High level routines for use by the bus drivers
991 extern int __must_check device_register(struct device *dev);
992 extern void device_unregister(struct device *dev);
993 extern void device_initialize(struct device *dev);
994 extern int __must_check device_add(struct device *dev);
995 extern void device_del(struct device *dev);
996 extern int device_for_each_child(struct device *dev, void *data,
997 int (*fn)(struct device *dev, void *data));
998 extern int device_for_each_child_reverse(struct device *dev, void *data,
999 int (*fn)(struct device *dev, void *data));
1000 extern struct device *device_find_child(struct device *dev, void *data,
1001 int (*match)(struct device *dev, void *data));
1002 extern int device_rename(struct device *dev, const char *new_name);
1003 extern int device_move(struct device *dev, struct device *new_parent,
1004 enum dpm_order dpm_order);
1005 extern const char *device_get_devnode(struct device *dev,
1006 umode_t *mode, kuid_t *uid, kgid_t *gid,
1009 static inline bool device_supports_offline(struct device *dev)
1011 return dev->bus && dev->bus->offline && dev->bus->online;
1014 extern void lock_device_hotplug(void);
1015 extern void unlock_device_hotplug(void);
1016 extern int lock_device_hotplug_sysfs(void);
1017 extern int device_offline(struct device *dev);
1018 extern int device_online(struct device *dev);
1019 extern void set_primary_fwnode(struct device *dev, struct fwnode_handle *fwnode);
1020 extern void set_secondary_fwnode(struct device *dev, struct fwnode_handle *fwnode);
1023 * Root device objects for grouping under /sys/devices
1025 extern struct device *__root_device_register(const char *name,
1026 struct module *owner);
1028 /* This is a macro to avoid include problems with THIS_MODULE */
1029 #define root_device_register(name) \
1030 __root_device_register(name, THIS_MODULE)
1032 extern void root_device_unregister(struct device *root);
1034 static inline void *dev_get_platdata(const struct device *dev)
1036 return dev->platform_data;
1040 * Manual binding of a device to driver. See drivers/base/bus.c
1041 * for information on use.
1043 extern int __must_check device_bind_driver(struct device *dev);
1044 extern void device_release_driver(struct device *dev);
1045 extern int __must_check device_attach(struct device *dev);
1046 extern int __must_check driver_attach(struct device_driver *drv);
1047 extern void device_initial_probe(struct device *dev);
1048 extern int __must_check device_reprobe(struct device *dev);
1051 * Easy functions for dynamically creating devices on the fly
1053 extern __printf(5, 0)
1054 struct device *device_create_vargs(struct class *cls, struct device *parent,
1055 dev_t devt, void *drvdata,
1056 const char *fmt, va_list vargs);
1057 extern __printf(5, 6)
1058 struct device *device_create(struct class *cls, struct device *parent,
1059 dev_t devt, void *drvdata,
1060 const char *fmt, ...);
1061 extern __printf(6, 7)
1062 struct device *device_create_with_groups(struct class *cls,
1063 struct device *parent, dev_t devt, void *drvdata,
1064 const struct attribute_group **groups,
1065 const char *fmt, ...);
1066 extern void device_destroy(struct class *cls, dev_t devt);
1069 * Platform "fixup" functions - allow the platform to have their say
1070 * about devices and actions that the general device layer doesn't
1073 /* Notify platform of device discovery */
1074 extern int (*platform_notify)(struct device *dev);
1076 extern int (*platform_notify_remove)(struct device *dev);
1080 * get_device - atomically increment the reference count for the device.
1083 extern struct device *get_device(struct device *dev);
1084 extern void put_device(struct device *dev);
1086 #ifdef CONFIG_DEVTMPFS
1087 extern int devtmpfs_create_node(struct device *dev);
1088 extern int devtmpfs_delete_node(struct device *dev);
1089 extern int devtmpfs_mount(const char *mntdir);
1091 static inline int devtmpfs_create_node(struct device *dev) { return 0; }
1092 static inline int devtmpfs_delete_node(struct device *dev) { return 0; }
1093 static inline int devtmpfs_mount(const char *mountpoint) { return 0; }
1096 /* drivers/base/power/shutdown.c */
1097 extern void device_shutdown(void);
1099 /* debugging and troubleshooting/diagnostic helpers. */
1100 extern const char *dev_driver_string(const struct device *dev);
1103 #ifdef CONFIG_PRINTK
1105 extern __printf(3, 0)
1106 int dev_vprintk_emit(int level, const struct device *dev,
1107 const char *fmt, va_list args);
1108 extern __printf(3, 4)
1109 int dev_printk_emit(int level, const struct device *dev, const char *fmt, ...);
1111 extern __printf(3, 4)
1112 void dev_printk(const char *level, const struct device *dev,
1113 const char *fmt, ...);
1114 extern __printf(2, 3)
1115 void dev_emerg(const struct device *dev, const char *fmt, ...);
1116 extern __printf(2, 3)
1117 void dev_alert(const struct device *dev, const char *fmt, ...);
1118 extern __printf(2, 3)
1119 void dev_crit(const struct device *dev, const char *fmt, ...);
1120 extern __printf(2, 3)
1121 void dev_err(const struct device *dev, const char *fmt, ...);
1122 extern __printf(2, 3)
1123 void dev_warn(const struct device *dev, const char *fmt, ...);
1124 extern __printf(2, 3)
1125 void dev_notice(const struct device *dev, const char *fmt, ...);
1126 extern __printf(2, 3)
1127 void _dev_info(const struct device *dev, const char *fmt, ...);
1131 static inline __printf(3, 0)
1132 int dev_vprintk_emit(int level, const struct device *dev,
1133 const char *fmt, va_list args)
1135 static inline __printf(3, 4)
1136 int dev_printk_emit(int level, const struct device *dev, const char *fmt, ...)
1139 static inline void __dev_printk(const char *level, const struct device *dev,
1140 struct va_format *vaf)
1142 static inline __printf(3, 4)
1143 void dev_printk(const char *level, const struct device *dev,
1144 const char *fmt, ...)
1147 static inline __printf(2, 3)
1148 void dev_emerg(const struct device *dev, const char *fmt, ...)
1150 static inline __printf(2, 3)
1151 void dev_crit(const struct device *dev, const char *fmt, ...)
1153 static inline __printf(2, 3)
1154 void dev_alert(const struct device *dev, const char *fmt, ...)
1156 static inline __printf(2, 3)
1157 void dev_err(const struct device *dev, const char *fmt, ...)
1159 static inline __printf(2, 3)
1160 void dev_warn(const struct device *dev, const char *fmt, ...)
1162 static inline __printf(2, 3)
1163 void dev_notice(const struct device *dev, const char *fmt, ...)
1165 static inline __printf(2, 3)
1166 void _dev_info(const struct device *dev, const char *fmt, ...)
1172 * Stupid hackaround for existing uses of non-printk uses dev_info
1174 * Note that the definition of dev_info below is actually _dev_info
1175 * and a macro is used to avoid redefining dev_info
1178 #define dev_info(dev, fmt, arg...) _dev_info(dev, fmt, ##arg)
1180 #if defined(CONFIG_DYNAMIC_DEBUG)
1181 #define dev_dbg(dev, format, ...) \
1183 dynamic_dev_dbg(dev, format, ##__VA_ARGS__); \
1185 #elif defined(DEBUG)
1186 #define dev_dbg(dev, format, arg...) \
1187 dev_printk(KERN_DEBUG, dev, format, ##arg)
1189 #define dev_dbg(dev, format, arg...) \
1192 dev_printk(KERN_DEBUG, dev, format, ##arg); \
1196 #ifdef CONFIG_PRINTK
1197 #define dev_level_once(dev_level, dev, fmt, ...) \
1199 static bool __print_once __read_mostly; \
1201 if (!__print_once) { \
1202 __print_once = true; \
1203 dev_level(dev, fmt, ##__VA_ARGS__); \
1207 #define dev_level_once(dev_level, dev, fmt, ...) \
1210 dev_level(dev, fmt, ##__VA_ARGS__); \
1214 #define dev_emerg_once(dev, fmt, ...) \
1215 dev_level_once(dev_emerg, dev, fmt, ##__VA_ARGS__)
1216 #define dev_alert_once(dev, fmt, ...) \
1217 dev_level_once(dev_alert, dev, fmt, ##__VA_ARGS__)
1218 #define dev_crit_once(dev, fmt, ...) \
1219 dev_level_once(dev_crit, dev, fmt, ##__VA_ARGS__)
1220 #define dev_err_once(dev, fmt, ...) \
1221 dev_level_once(dev_err, dev, fmt, ##__VA_ARGS__)
1222 #define dev_warn_once(dev, fmt, ...) \
1223 dev_level_once(dev_warn, dev, fmt, ##__VA_ARGS__)
1224 #define dev_notice_once(dev, fmt, ...) \
1225 dev_level_once(dev_notice, dev, fmt, ##__VA_ARGS__)
1226 #define dev_info_once(dev, fmt, ...) \
1227 dev_level_once(dev_info, dev, fmt, ##__VA_ARGS__)
1228 #define dev_dbg_once(dev, fmt, ...) \
1229 dev_level_once(dev_dbg, dev, fmt, ##__VA_ARGS__)
1231 #define dev_level_ratelimited(dev_level, dev, fmt, ...) \
1233 static DEFINE_RATELIMIT_STATE(_rs, \
1234 DEFAULT_RATELIMIT_INTERVAL, \
1235 DEFAULT_RATELIMIT_BURST); \
1236 if (__ratelimit(&_rs)) \
1237 dev_level(dev, fmt, ##__VA_ARGS__); \
1240 #define dev_emerg_ratelimited(dev, fmt, ...) \
1241 dev_level_ratelimited(dev_emerg, dev, fmt, ##__VA_ARGS__)
1242 #define dev_alert_ratelimited(dev, fmt, ...) \
1243 dev_level_ratelimited(dev_alert, dev, fmt, ##__VA_ARGS__)
1244 #define dev_crit_ratelimited(dev, fmt, ...) \
1245 dev_level_ratelimited(dev_crit, dev, fmt, ##__VA_ARGS__)
1246 #define dev_err_ratelimited(dev, fmt, ...) \
1247 dev_level_ratelimited(dev_err, dev, fmt, ##__VA_ARGS__)
1248 #define dev_warn_ratelimited(dev, fmt, ...) \
1249 dev_level_ratelimited(dev_warn, dev, fmt, ##__VA_ARGS__)
1250 #define dev_notice_ratelimited(dev, fmt, ...) \
1251 dev_level_ratelimited(dev_notice, dev, fmt, ##__VA_ARGS__)
1252 #define dev_info_ratelimited(dev, fmt, ...) \
1253 dev_level_ratelimited(dev_info, dev, fmt, ##__VA_ARGS__)
1254 #if defined(CONFIG_DYNAMIC_DEBUG)
1255 /* descriptor check is first to prevent flooding with "callbacks suppressed" */
1256 #define dev_dbg_ratelimited(dev, fmt, ...) \
1258 static DEFINE_RATELIMIT_STATE(_rs, \
1259 DEFAULT_RATELIMIT_INTERVAL, \
1260 DEFAULT_RATELIMIT_BURST); \
1261 DEFINE_DYNAMIC_DEBUG_METADATA(descriptor, fmt); \
1262 if (unlikely(descriptor.flags & _DPRINTK_FLAGS_PRINT) && \
1263 __ratelimit(&_rs)) \
1264 __dynamic_dev_dbg(&descriptor, dev, fmt, \
1267 #elif defined(DEBUG)
1268 #define dev_dbg_ratelimited(dev, fmt, ...) \
1270 static DEFINE_RATELIMIT_STATE(_rs, \
1271 DEFAULT_RATELIMIT_INTERVAL, \
1272 DEFAULT_RATELIMIT_BURST); \
1273 if (__ratelimit(&_rs)) \
1274 dev_printk(KERN_DEBUG, dev, fmt, ##__VA_ARGS__); \
1277 #define dev_dbg_ratelimited(dev, fmt, ...) \
1280 dev_printk(KERN_DEBUG, dev, fmt, ##__VA_ARGS__); \
1284 #ifdef VERBOSE_DEBUG
1285 #define dev_vdbg dev_dbg
1287 #define dev_vdbg(dev, format, arg...) \
1290 dev_printk(KERN_DEBUG, dev, format, ##arg); \
1295 * dev_WARN*() acts like dev_printk(), but with the key difference of
1296 * using WARN/WARN_ONCE to include file/line information and a backtrace.
1298 #define dev_WARN(dev, format, arg...) \
1299 WARN(1, "%s %s: " format, dev_driver_string(dev), dev_name(dev), ## arg);
1301 #define dev_WARN_ONCE(dev, condition, format, arg...) \
1302 WARN_ONCE(condition, "%s %s: " format, \
1303 dev_driver_string(dev), dev_name(dev), ## arg)
1305 /* Create alias, so I can be autoloaded. */
1306 #define MODULE_ALIAS_CHARDEV(major,minor) \
1307 MODULE_ALIAS("char-major-" __stringify(major) "-" __stringify(minor))
1308 #define MODULE_ALIAS_CHARDEV_MAJOR(major) \
1309 MODULE_ALIAS("char-major-" __stringify(major) "-*")
1311 #ifdef CONFIG_SYSFS_DEPRECATED
1312 extern long sysfs_deprecated;
1314 #define sysfs_deprecated 0
1318 * module_driver() - Helper macro for drivers that don't do anything
1319 * special in module init/exit. This eliminates a lot of boilerplate.
1320 * Each module may only use this macro once, and calling it replaces
1321 * module_init() and module_exit().
1323 * @__driver: driver name
1324 * @__register: register function for this driver type
1325 * @__unregister: unregister function for this driver type
1326 * @...: Additional arguments to be passed to __register and __unregister.
1328 * Use this macro to construct bus specific macros for registering
1329 * drivers, and do not use it on its own.
1331 #define module_driver(__driver, __register, __unregister, ...) \
1332 static int __init __driver##_init(void) \
1334 return __register(&(__driver) , ##__VA_ARGS__); \
1336 module_init(__driver##_init); \
1337 static void __exit __driver##_exit(void) \
1339 __unregister(&(__driver) , ##__VA_ARGS__); \
1341 module_exit(__driver##_exit);
1344 * builtin_driver() - Helper macro for drivers that don't do anything
1345 * special in init and have no exit. This eliminates some boilerplate.
1346 * Each driver may only use this macro once, and calling it replaces
1347 * device_initcall (or in some cases, the legacy __initcall). This is
1348 * meant to be a direct parallel of module_driver() above but without
1349 * the __exit stuff that is not used for builtin cases.
1351 * @__driver: driver name
1352 * @__register: register function for this driver type
1353 * @...: Additional arguments to be passed to __register
1355 * Use this macro to construct bus specific macros for registering
1356 * drivers, and do not use it on its own.
1358 #define builtin_driver(__driver, __register, ...) \
1359 static int __init __driver##_init(void) \
1361 return __register(&(__driver) , ##__VA_ARGS__); \
1363 device_initcall(__driver##_init);
1365 #endif /* _DEVICE_H_ */