1 /*
2 * device.h - generic, centralized driver model
3 *
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.
7 *
8 * This file is released under the GPLv2
9 *
10 * See Documentation/driver-model/ for more information.
11 */
12
13 #ifndef _DEVICE_H_
14 #define _DEVICE_H_
15
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>
25 #include <linux/pm.h>
26 #include <linux/atomic.h>
27 #include <linux/ratelimit.h>
28 #include <linux/uidgid.h>
29 #include <asm/device.h>
30
31 struct device;
32 struct device_private;
33 struct device_driver;
34 struct driver_private;
35 struct module;
36 struct class;
37 struct subsys_private;
38 struct bus_type;
39 struct device_node;
40 struct iommu_ops;
41 struct iommu_group;
42
43 struct bus_attribute {
44 struct attribute attr;
45 ssize_t (*show)(struct bus_type *bus, char *buf);
46 ssize_t (*store)(struct bus_type *bus, const char *buf, size_t count);
47 };
48
49 #define BUS_ATTR(_name, _mode, _show, _store) \
50 struct bus_attribute bus_attr_##_name = __ATTR(_name, _mode, _show, _store)
51
52 extern int __must_check bus_create_file(struct bus_type *,
53 struct bus_attribute *);
54 extern void bus_remove_file(struct bus_type *, struct bus_attribute *);
55
56 /**
57 * struct bus_type - The bus type of the device
58 *
59 * @name: The name of the bus.
60 * @dev_name: Used for subsystems to enumerate devices like ("foo%u", dev->id).
61 * @dev_root: Default device to use as the parent.
62 * @bus_attrs: Default attributes of the bus.
63 * @dev_attrs: Default attributes of the devices on the bus.
64 * @drv_attrs: Default attributes of the device drivers on the bus.
65 * @match: Called, perhaps multiple times, whenever a new device or driver
66 * is added for this bus. It should return a nonzero value if the
67 * given device can be handled by the given driver.
68 * @uevent: Called when a device is added, removed, or a few other things
69 * that generate uevents to add the environment variables.
70 * @probe: Called when a new device or driver add to this bus, and callback
71 * the specific driver's probe to initial the matched device.
72 * @remove: Called when a device removed from this bus.
73 * @shutdown: Called at shut-down time to quiesce the device.
74 * @suspend: Called when a device on this bus wants to go to sleep mode.
75 * @resume: Called to bring a device on this bus out of sleep mode.
76 * @pm: Power management operations of this bus, callback the specific
77 * device driver's pm-ops.
78 * @iommu_ops: IOMMU specific operations for this bus, used to attach IOMMU
79 * driver implementations to a bus and allow the driver to do
80 * bus-specific setup
81 * @p: The private data of the driver core, only the driver core can
82 * touch this.
83 *
84 * A bus is a channel between the processor and one or more devices. For the
85 * purposes of the device model, all devices are connected via a bus, even if
86 * it is an internal, virtual, "platform" bus. Buses can plug into each other.
87 * A USB controller is usually a PCI device, for example. The device model
88 * represents the actual connections between buses and the devices they control.
89 * A bus is represented by the bus_type structure. It contains the name, the
90 * default attributes, the bus' methods, PM operations, and the driver core's
91 * private data.
92 */
93 struct bus_type {
94 const char *name;
95 const char *dev_name;
96 struct device *dev_root;
97 struct bus_attribute *bus_attrs;
98 struct device_attribute *dev_attrs;
99 struct driver_attribute *drv_attrs;
100
101 int (*match)(struct device *dev, struct device_driver *drv);
102 int (*uevent)(struct device *dev, struct kobj_uevent_env *env);
103 int (*probe)(struct device *dev);
104 int (*remove)(struct device *dev);
105 void (*shutdown)(struct device *dev);
106
107 int (*suspend)(struct device *dev, pm_message_t state);
108 int (*resume)(struct device *dev);
109
110 const struct dev_pm_ops *pm;
111
112 struct iommu_ops *iommu_ops;
113
114 struct subsys_private *p;
115 struct lock_class_key lock_key;
116 };
117
118 extern int __must_check bus_register(struct bus_type *bus);
119
120 extern void bus_unregister(struct bus_type *bus);
121
122 extern int __must_check bus_rescan_devices(struct bus_type *bus);
123
124 /* iterator helpers for buses */
125 struct subsys_dev_iter {
126 struct klist_iter ki;
127 const struct device_type *type;
128 };
129 void subsys_dev_iter_init(struct subsys_dev_iter *iter,
130 struct bus_type *subsys,
131 struct device *start,
132 const struct device_type *type);
133 struct device *subsys_dev_iter_next(struct subsys_dev_iter *iter);
134 void subsys_dev_iter_exit(struct subsys_dev_iter *iter);
135
136 int bus_for_each_dev(struct bus_type *bus, struct device *start, void *data,
137 int (*fn)(struct device *dev, void *data));
138 struct device *bus_find_device(struct bus_type *bus, struct device *start,
139 void *data,
140 int (*match)(struct device *dev, void *data));
141 struct device *bus_find_device_by_name(struct bus_type *bus,
142 struct device *start,
143 const char *name);
144 struct device *subsys_find_device_by_id(struct bus_type *bus, unsigned int id,
145 struct device *hint);
146 int bus_for_each_drv(struct bus_type *bus, struct device_driver *start,
147 void *data, int (*fn)(struct device_driver *, void *));
148 void bus_sort_breadthfirst(struct bus_type *bus,
149 int (*compare)(const struct device *a,
150 const struct device *b));
151 /*
152 * Bus notifiers: Get notified of addition/removal of devices
153 * and binding/unbinding of drivers to devices.
154 * In the long run, it should be a replacement for the platform
155 * notify hooks.
156 */
157 struct notifier_block;
158
159 extern int bus_register_notifier(struct bus_type *bus,
160 struct notifier_block *nb);
161 extern int bus_unregister_notifier(struct bus_type *bus,
162 struct notifier_block *nb);
163
164 /* All 4 notifers below get called with the target struct device *
165 * as an argument. Note that those functions are likely to be called
166 * with the device lock held in the core, so be careful.
167 */
168 #define BUS_NOTIFY_ADD_DEVICE 0x00000001 /* device added */
169 #define BUS_NOTIFY_DEL_DEVICE 0x00000002 /* device removed */
170 #define BUS_NOTIFY_BIND_DRIVER 0x00000003 /* driver about to be
171 bound */
172 #define BUS_NOTIFY_BOUND_DRIVER 0x00000004 /* driver bound to device */
173 #define BUS_NOTIFY_UNBIND_DRIVER 0x00000005 /* driver about to be
174 unbound */
175 #define BUS_NOTIFY_UNBOUND_DRIVER 0x00000006 /* driver is unbound
176 from the device */
177
178 extern struct kset *bus_get_kset(struct bus_type *bus);
179 extern struct klist *bus_get_device_klist(struct bus_type *bus);
180
181 /**
182 * struct device_driver - The basic device driver structure
183 * @name: Name of the device driver.
184 * @bus: The bus which the device of this driver belongs to.
185 * @owner: The module owner.
186 * @mod_name: Used for built-in modules.
187 * @suppress_bind_attrs: Disables bind/unbind via sysfs.
188 * @of_match_table: The open firmware table.
189 * @acpi_match_table: The ACPI match table.
190 * @probe: Called to query the existence of a specific device,
191 * whether this driver can work with it, and bind the driver
192 * to a specific device.
193 * @remove: Called when the device is removed from the system to
194 * unbind a device from this driver.
195 * @shutdown: Called at shut-down time to quiesce the device.
196 * @suspend: Called to put the device to sleep mode. Usually to a
197 * low power state.
198 * @resume: Called to bring a device from sleep mode.
199 * @groups: Default attributes that get created by the driver core
200 * automatically.
201 * @pm: Power management operations of the device which matched
202 * this driver.
203 * @p: Driver core's private data, no one other than the driver
204 * core can touch this.
205 *
206 * The device driver-model tracks all of the drivers known to the system.
207 * The main reason for this tracking is to enable the driver core to match
208 * up drivers with new devices. Once drivers are known objects within the
209 * system, however, a number of other things become possible. Device drivers
210 * can export information and configuration variables that are independent
211 * of any specific device.
212 */
213 struct device_driver {
214 const char *name;
215 struct bus_type *bus;
216
217 struct module *owner;
218 const char *mod_name; /* used for built-in modules */
219
220 bool suppress_bind_attrs; /* disables bind/unbind via sysfs */
221
222 const struct of_device_id *of_match_table;
223 const struct acpi_device_id *acpi_match_table;
224
225 int (*probe) (struct device *dev);
226 int (*remove) (struct device *dev);
227 void (*shutdown) (struct device *dev);
228 int (*suspend) (struct device *dev, pm_message_t state);
229 int (*resume) (struct device *dev);
230 const struct attribute_group **groups;
231
232 const struct dev_pm_ops *pm;
233
234 struct driver_private *p;
235 };
236
237
238 extern int __must_check driver_register(struct device_driver *drv);
239 extern void driver_unregister(struct device_driver *drv);
240
241 extern struct device_driver *driver_find(const char *name,
242 struct bus_type *bus);
243 extern int driver_probe_done(void);
244 extern void wait_for_device_probe(void);
245
246
247 /* sysfs interface for exporting driver attributes */
248
249 struct driver_attribute {
250 struct attribute attr;
251 ssize_t (*show)(struct device_driver *driver, char *buf);
252 ssize_t (*store)(struct device_driver *driver, const char *buf,
253 size_t count);
254 };
255
256 #define DRIVER_ATTR(_name, _mode, _show, _store) \
257 struct driver_attribute driver_attr_##_name = \
258 __ATTR(_name, _mode, _show, _store)
259
260 extern int __must_check driver_create_file(struct device_driver *driver,
261 const struct driver_attribute *attr);
262 extern void driver_remove_file(struct device_driver *driver,
263 const struct driver_attribute *attr);
264
265 extern int __must_check driver_for_each_device(struct device_driver *drv,
266 struct device *start,
267 void *data,
268 int (*fn)(struct device *dev,
269 void *));
270 struct device *driver_find_device(struct device_driver *drv,
271 struct device *start, void *data,
272 int (*match)(struct device *dev, void *data));
273
274 /**
275 * struct subsys_interface - interfaces to device functions
276 * @name: name of the device function
277 * @subsys: subsytem of the devices to attach to
278 * @node: the list of functions registered at the subsystem
279 * @add_dev: device hookup to device function handler
280 * @remove_dev: device hookup to device function handler
281 *
282 * Simple interfaces attached to a subsystem. Multiple interfaces can
283 * attach to a subsystem and its devices. Unlike drivers, they do not
284 * exclusively claim or control devices. Interfaces usually represent
285 * a specific functionality of a subsystem/class of devices.
286 */
287 struct subsys_interface {
288 const char *name;
289 struct bus_type *subsys;
290 struct list_head node;
291 int (*add_dev)(struct device *dev, struct subsys_interface *sif);
292 int (*remove_dev)(struct device *dev, struct subsys_interface *sif);
293 };
294
295 int subsys_interface_register(struct subsys_interface *sif);
296 void subsys_interface_unregister(struct subsys_interface *sif);
297
298 int subsys_system_register(struct bus_type *subsys,
299 const struct attribute_group **groups);
300 int subsys_virtual_register(struct bus_type *subsys,
301 const struct attribute_group **groups);
302
303 /**
304 * struct class - device classes
305 * @name: Name of the class.
306 * @owner: The module owner.
307 * @class_attrs: Default attributes of this class.
308 * @dev_attrs: Default attributes of the devices belong to the class.
309 * @dev_bin_attrs: Default binary attributes of the devices belong to the class.
310 * @dev_kobj: The kobject that represents this class and links it into the hierarchy.
311 * @dev_uevent: Called when a device is added, removed from this class, or a
312 * few other things that generate uevents to add the environment
313 * variables.
314 * @devnode: Callback to provide the devtmpfs.
315 * @class_release: Called to release this class.
316 * @dev_release: Called to release the device.
317 * @suspend: Used to put the device to sleep mode, usually to a low power
318 * state.
319 * @resume: Used to bring the device from the sleep mode.
320 * @ns_type: Callbacks so sysfs can detemine namespaces.
321 * @namespace: Namespace of the device belongs to this class.
322 * @pm: The default device power management operations of this class.
323 * @p: The private data of the driver core, no one other than the
324 * driver core can touch this.
325 *
326 * A class is a higher-level view of a device that abstracts out low-level
327 * implementation details. Drivers may see a SCSI disk or an ATA disk, but,
328 * at the class level, they are all simply disks. Classes allow user space
329 * to work with devices based on what they do, rather than how they are
330 * connected or how they work.
331 */
332 struct class {
333 const char *name;
334 struct module *owner;
335
336 struct class_attribute *class_attrs;
337 struct device_attribute *dev_attrs;
338 struct bin_attribute *dev_bin_attrs;
339 struct kobject *dev_kobj;
340
341 int (*dev_uevent)(struct device *dev, struct kobj_uevent_env *env);
342 char *(*devnode)(struct device *dev, umode_t *mode);
343
344 void (*class_release)(struct class *class);
345 void (*dev_release)(struct device *dev);
346
347 int (*suspend)(struct device *dev, pm_message_t state);
348 int (*resume)(struct device *dev);
349
350 const struct kobj_ns_type_operations *ns_type;
351 const void *(*namespace)(struct device *dev);
352
353 const struct dev_pm_ops *pm;
354
355 struct subsys_private *p;
356 };
357
358 struct class_dev_iter {
359 struct klist_iter ki;
360 const struct device_type *type;
361 };
362
363 extern struct kobject *sysfs_dev_block_kobj;
364 extern struct kobject *sysfs_dev_char_kobj;
365 extern int __must_check __class_register(struct class *class,
366 struct lock_class_key *key);
367 extern void class_unregister(struct class *class);
368
369 /* This is a #define to keep the compiler from merging different
370 * instances of the __key variable */
371 #define class_register(class) \
372 ({ \
373 static struct lock_class_key __key; \
374 __class_register(class, &__key); \
375 })
376
377 struct class_compat;
378 struct class_compat *class_compat_register(const char *name);
379 void class_compat_unregister(struct class_compat *cls);
380 int class_compat_create_link(struct class_compat *cls, struct device *dev,
381 struct device *device_link);
382 void class_compat_remove_link(struct class_compat *cls, struct device *dev,
383 struct device *device_link);
384
385 extern void class_dev_iter_init(struct class_dev_iter *iter,
386 struct class *class,
387 struct device *start,
388 const struct device_type *type);
389 extern struct device *class_dev_iter_next(struct class_dev_iter *iter);
390 extern void class_dev_iter_exit(struct class_dev_iter *iter);
391
392 extern int class_for_each_device(struct class *class, struct device *start,
393 void *data,
394 int (*fn)(struct device *dev, void *data));
395 extern struct device *class_find_device(struct class *class,
396 struct device *start, const void *data,
397 int (*match)(struct device *, const void *));
398
399 struct class_attribute {
400 struct attribute attr;
401 ssize_t (*show)(struct class *class, struct class_attribute *attr,
402 char *buf);
403 ssize_t (*store)(struct class *class, struct class_attribute *attr,
404 const char *buf, size_t count);
405 const void *(*namespace)(struct class *class,
406 const struct class_attribute *attr);
407 };
408
409 #define CLASS_ATTR(_name, _mode, _show, _store) \
410 struct class_attribute class_attr_##_name = __ATTR(_name, _mode, _show, _store)
411
412 extern int __must_check class_create_file(struct class *class,
413 const struct class_attribute *attr);
414 extern void class_remove_file(struct class *class,
415 const struct class_attribute *attr);
416
417 /* Simple class attribute that is just a static string */
418
419 struct class_attribute_string {
420 struct class_attribute attr;
421 char *str;
422 };
423
424 /* Currently read-only only */
425 #define _CLASS_ATTR_STRING(_name, _mode, _str) \
426 { __ATTR(_name, _mode, show_class_attr_string, NULL), _str }
427 #define CLASS_ATTR_STRING(_name, _mode, _str) \
428 struct class_attribute_string class_attr_##_name = \
429 _CLASS_ATTR_STRING(_name, _mode, _str)
430
431 extern ssize_t show_class_attr_string(struct class *class, struct class_attribute *attr,
432 char *buf);
433
434 struct class_interface {
435 struct list_head node;
436 struct class *class;
437
438 int (*add_dev) (struct device *, struct class_interface *);
439 void (*remove_dev) (struct device *, struct class_interface *);
440 };
441
442 extern int __must_check class_interface_register(struct class_interface *);
443 extern void class_interface_unregister(struct class_interface *);
444
445 extern struct class * __must_check __class_create(struct module *owner,
446 const char *name,
447 struct lock_class_key *key);
448 extern void class_destroy(struct class *cls);
449
450 /* This is a #define to keep the compiler from merging different
451 * instances of the __key variable */
452 #define class_create(owner, name) \
453 ({ \
454 static struct lock_class_key __key; \
455 __class_create(owner, name, &__key); \
456 })
457
458 /*
459 * The type of device, "struct device" is embedded in. A class
460 * or bus can contain devices of different types
461 * like "partitions" and "disks", "mouse" and "event".
462 * This identifies the device type and carries type-specific
463 * information, equivalent to the kobj_type of a kobject.
464 * If "name" is specified, the uevent will contain it in
465 * the DEVTYPE variable.
466 */
467 struct device_type {
468 const char *name;
469 const struct attribute_group **groups;
470 int (*uevent)(struct device *dev, struct kobj_uevent_env *env);
471 char *(*devnode)(struct device *dev, umode_t *mode,
472 kuid_t *uid, kgid_t *gid);
473 void (*release)(struct device *dev);
474
475 const struct dev_pm_ops *pm;
476 };
477
478 /* interface for exporting device attributes */
479 struct device_attribute {
480 struct attribute attr;
481 ssize_t (*show)(struct device *dev, struct device_attribute *attr,
482 char *buf);
483 ssize_t (*store)(struct device *dev, struct device_attribute *attr,
484 const char *buf, size_t count);
485 };
486
487 struct dev_ext_attribute {
488 struct device_attribute attr;
489 void *var;
490 };
491
492 ssize_t device_show_ulong(struct device *dev, struct device_attribute *attr,
493 char *buf);
494 ssize_t device_store_ulong(struct device *dev, struct device_attribute *attr,
495 const char *buf, size_t count);
496 ssize_t device_show_int(struct device *dev, struct device_attribute *attr,
497 char *buf);
498 ssize_t device_store_int(struct device *dev, struct device_attribute *attr,
499 const char *buf, size_t count);
500 ssize_t device_show_bool(struct device *dev, struct device_attribute *attr,
501 char *buf);
502 ssize_t device_store_bool(struct device *dev, struct device_attribute *attr,
503 const char *buf, size_t count);
504
505 #define DEVICE_ATTR(_name, _mode, _show, _store) \
506 struct device_attribute dev_attr_##_name = __ATTR(_name, _mode, _show, _store)
507 #define DEVICE_ULONG_ATTR(_name, _mode, _var) \
508 struct dev_ext_attribute dev_attr_##_name = \
509 { __ATTR(_name, _mode, device_show_ulong, device_store_ulong), &(_var) }
510 #define DEVICE_INT_ATTR(_name, _mode, _var) \
511 struct dev_ext_attribute dev_attr_##_name = \
512 { __ATTR(_name, _mode, device_show_int, device_store_int), &(_var) }
513 #define DEVICE_BOOL_ATTR(_name, _mode, _var) \
514 struct dev_ext_attribute dev_attr_##_name = \
515 { __ATTR(_name, _mode, device_show_bool, device_store_bool), &(_var) }
516 #define DEVICE_ATTR_IGNORE_LOCKDEP(_name, _mode, _show, _store) \
517 struct device_attribute dev_attr_##_name = \
518 __ATTR_IGNORE_LOCKDEP(_name, _mode, _show, _store)
519
520 extern int device_create_file(struct device *device,
521 const struct device_attribute *entry);
522 extern void device_remove_file(struct device *dev,
523 const struct device_attribute *attr);
524 extern int __must_check device_create_bin_file(struct device *dev,
525 const struct bin_attribute *attr);
526 extern void device_remove_bin_file(struct device *dev,
527 const struct bin_attribute *attr);
528 extern int device_schedule_callback_owner(struct device *dev,
529 void (*func)(struct device *dev), struct module *owner);
530
531 /* This is a macro to avoid include problems with THIS_MODULE */
532 #define device_schedule_callback(dev, func) \
533 device_schedule_callback_owner(dev, func, THIS_MODULE)
534
535 /* device resource management */
536 typedef void (*dr_release_t)(struct device *dev, void *res);
537 typedef int (*dr_match_t)(struct device *dev, void *res, void *match_data);
538
539 #ifdef CONFIG_DEBUG_DEVRES
540 extern void *__devres_alloc(dr_release_t release, size_t size, gfp_t gfp,
541 const char *name);
542 #define devres_alloc(release, size, gfp) \
543 __devres_alloc(release, size, gfp, #release)
544 #else
545 extern void *devres_alloc(dr_release_t release, size_t size, gfp_t gfp);
546 #endif
547 extern void devres_for_each_res(struct device *dev, dr_release_t release,
548 dr_match_t match, void *match_data,
549 void (*fn)(struct device *, void *, void *),
550 void *data);
551 extern void devres_free(void *res);
552 extern void devres_add(struct device *dev, void *res);
553 extern void *devres_find(struct device *dev, dr_release_t release,
554 dr_match_t match, void *match_data);
555 extern void *devres_get(struct device *dev, void *new_res,
556 dr_match_t match, void *match_data);
557 extern void *devres_remove(struct device *dev, dr_release_t release,
558 dr_match_t match, void *match_data);
559 extern int devres_destroy(struct device *dev, dr_release_t release,
560 dr_match_t match, void *match_data);
561 extern int devres_release(struct device *dev, dr_release_t release,
562 dr_match_t match, void *match_data);
563
564 /* devres group */
565 extern void * __must_check devres_open_group(struct device *dev, void *id,
566 gfp_t gfp);
567 extern void devres_close_group(struct device *dev, void *id);
568 extern void devres_remove_group(struct device *dev, void *id);
569 extern int devres_release_group(struct device *dev, void *id);
570
571 /* managed kzalloc/kfree for device drivers, no kmalloc, always use kzalloc */
572 extern void *devm_kzalloc(struct device *dev, size_t size, gfp_t gfp);
573 extern void devm_kfree(struct device *dev, void *p);
574
575 void __iomem *devm_ioremap_resource(struct device *dev, struct resource *res);
576 void __iomem *devm_request_and_ioremap(struct device *dev,
577 struct resource *res);
578
579 /* allows to add/remove a custom action to devres stack */
580 int devm_add_action(struct device *dev, void (*action)(void *), void *data);
581 void devm_remove_action(struct device *dev, void (*action)(void *), void *data);
582
583 struct device_dma_parameters {
584 /*
585 * a low level driver may set these to teach IOMMU code about
586 * sg limitations.
587 */
588 unsigned int max_segment_size;
589 unsigned long segment_boundary_mask;
590 };
591
592 struct acpi_dev_node {
593 #ifdef CONFIG_ACPI
594 void *handle;
595 #endif
596 };
597
598 /**
599 * struct device - The basic device structure
600 * @parent: The device's "parent" device, the device to which it is attached.
601 * In most cases, a parent device is some sort of bus or host
602 * controller. If parent is NULL, the device, is a top-level device,
603 * which is not usually what you want.
604 * @p: Holds the private data of the driver core portions of the device.
605 * See the comment of the struct device_private for detail.
606 * @kobj: A top-level, abstract class from which other classes are derived.
607 * @init_name: Initial name of the device.
608 * @type: The type of device.
609 * This identifies the device type and carries type-specific
610 * information.
611 * @mutex: Mutex to synchronize calls to its driver.
612 * @bus: Type of bus device is on.
613 * @driver: Which driver has allocated this
614 * @platform_data: Platform data specific to the device.
615 * Example: For devices on custom boards, as typical of embedded
616 * and SOC based hardware, Linux often uses platform_data to point
617 * to board-specific structures describing devices and how they
618 * are wired. That can include what ports are available, chip
619 * variants, which GPIO pins act in what additional roles, and so
620 * on. This shrinks the "Board Support Packages" (BSPs) and
621 * minimizes board-specific #ifdefs in drivers.
622 * @power: For device power management.
623 * See Documentation/power/devices.txt for details.
624 * @pm_domain: Provide callbacks that are executed during system suspend,
625 * hibernation, system resume and during runtime PM transitions
626 * along with subsystem-level and driver-level callbacks.
627 * @pins: For device pin management.
628 * See Documentation/pinctrl.txt for details.
629 * @numa_node: NUMA node this device is close to.
630 * @dma_mask: Dma mask (if dma'ble device).
631 * @coherent_dma_mask: Like dma_mask, but for alloc_coherent mapping as not all
632 * hardware supports 64-bit addresses for consistent allocations
633 * such descriptors.
634 * @dma_parms: A low level driver may set these to teach IOMMU code about
635 * segment limitations.
636 * @dma_pools: Dma pools (if dma'ble device).
637 * @dma_mem: Internal for coherent mem override.
638 * @archdata: For arch-specific additions.
639 * @of_node: Associated device tree node.
640 * @acpi_node: Associated ACPI device node.
641 * @devt: For creating the sysfs "dev".
642 * @id: device instance
643 * @devres_lock: Spinlock to protect the resource of the device.
644 * @devres_head: The resources list of the device.
645 * @knode_class: The node used to add the device to the class list.
646 * @class: The class of the device.
647 * @groups: Optional attribute groups.
648 * @release: Callback to free the device after all references have
649 * gone away. This should be set by the allocator of the
650 * device (i.e. the bus driver that discovered the device).
651 *
652 * At the lowest level, every device in a Linux system is represented by an
653 * instance of struct device. The device structure contains the information
654 * that the device model core needs to model the system. Most subsystems,
655 * however, track additional information about the devices they host. As a
656 * result, it is rare for devices to be represented by bare device structures;
657 * instead, that structure, like kobject structures, is usually embedded within
658 * a higher-level representation of the device.
659 */
660 struct device {
661 struct device *parent;
662
663 struct device_private *p;
664
665 struct kobject kobj;
666 const char *init_name; /* initial name of the device */
667 const struct device_type *type;
668
669 struct mutex mutex; /* mutex to synchronize calls to
670 * its driver.
671 */
672
673 struct bus_type *bus; /* type of bus device is on */
674 struct device_driver *driver; /* which driver has allocated this
675 device */
676 void *platform_data; /* Platform specific data, device
677 core doesn't touch it */
678 struct dev_pm_info power;
679 struct dev_pm_domain *pm_domain;
680
681 #ifdef CONFIG_PINCTRL
682 struct dev_pin_info *pins;
683 #endif
684
685 #ifdef CONFIG_NUMA
686 int numa_node; /* NUMA node this device is close to */
687 #endif
688 u64 *dma_mask; /* dma mask (if dma'able device) */
689 u64 coherent_dma_mask;/* Like dma_mask, but for
690 alloc_coherent mappings as
691 not all hardware supports
692 64 bit addresses for consistent
693 allocations such descriptors. */
694
695 struct device_dma_parameters *dma_parms;
696
697 struct list_head dma_pools; /* dma pools (if dma'ble) */
698
699 struct dma_coherent_mem *dma_mem; /* internal for coherent mem
700 override */
701 #ifdef CONFIG_CMA
702 struct cma *cma_area; /* contiguous memory area for dma
703 allocations */
704 #endif
705 /* arch specific additions */
706 struct dev_archdata archdata;
707
708 struct device_node *of_node; /* associated device tree node */
709 struct acpi_dev_node acpi_node; /* associated ACPI device node */
710
711 dev_t devt; /* dev_t, creates the sysfs "dev" */
712 u32 id; /* device instance */
713
714 spinlock_t devres_lock;
715 struct list_head devres_head;
716
717 struct klist_node knode_class;
718 struct class *class;
719 const struct attribute_group **groups; /* optional groups */
720
721 void (*release)(struct device *dev);
722 struct iommu_group *iommu_group;
723 };
724
725 static inline struct device *kobj_to_dev(struct kobject *kobj)
726 {
727 return container_of(kobj, struct device, kobj);
728 }
729
730 #ifdef CONFIG_ACPI
731 #define ACPI_HANDLE(dev) ((dev)->acpi_node.handle)
732 #define ACPI_HANDLE_SET(dev, _handle_) (dev)->acpi_node.handle = (_handle_)
733 #else
734 #define ACPI_HANDLE(dev) (NULL)
735 #define ACPI_HANDLE_SET(dev, _handle_) do { } while (0)
736 #endif
737
738 /* Get the wakeup routines, which depend on struct device */
739 #include <linux/pm_wakeup.h>
740
741 static inline const char *dev_name(const struct device *dev)
742 {
743 /* Use the init name until the kobject becomes available */
744 if (dev->init_name)
745 return dev->init_name;
746
747 return kobject_name(&dev->kobj);
748 }
749
750 extern __printf(2, 3)
751 int dev_set_name(struct device *dev, const char *name, ...);
752
753 #ifdef CONFIG_NUMA
754 static inline int dev_to_node(struct device *dev)
755 {
756 return dev->numa_node;
757 }
758 static inline void set_dev_node(struct device *dev, int node)
759 {
760 dev->numa_node = node;
761 }
762 #else
763 static inline int dev_to_node(struct device *dev)
764 {
765 return -1;
766 }
767 static inline void set_dev_node(struct device *dev, int node)
768 {
769 }
770 #endif
771
772 static inline struct pm_subsys_data *dev_to_psd(struct device *dev)
773 {
774 return dev ? dev->power.subsys_data : NULL;
775 }
776
777 static inline unsigned int dev_get_uevent_suppress(const struct device *dev)
778 {
779 return dev->kobj.uevent_suppress;
780 }
781
782 static inline void dev_set_uevent_suppress(struct device *dev, int val)
783 {
784 dev->kobj.uevent_suppress = val;
785 }
786
787 static inline int device_is_registered(struct device *dev)
788 {
789 return dev->kobj.state_in_sysfs;
790 }
791
792 static inline void device_enable_async_suspend(struct device *dev)
793 {
794 if (!dev->power.is_prepared)
795 dev->power.async_suspend = true;
796 }
797
798 static inline void device_disable_async_suspend(struct device *dev)
799 {
800 if (!dev->power.is_prepared)
801 dev->power.async_suspend = false;
802 }
803
804 static inline bool device_async_suspend_enabled(struct device *dev)
805 {
806 return !!dev->power.async_suspend;
807 }
808
809 static inline void pm_suspend_ignore_children(struct device *dev, bool enable)
810 {
811 dev->power.ignore_children = enable;
812 }
813
814 static inline void dev_pm_syscore_device(struct device *dev, bool val)
815 {
816 #ifdef CONFIG_PM_SLEEP
817 dev->power.syscore = val;
818 #endif
819 }
820
821 static inline void device_lock(struct device *dev)
822 {
823 mutex_lock(&dev->mutex);
824 }
825
826 static inline int device_trylock(struct device *dev)
827 {
828 return mutex_trylock(&dev->mutex);
829 }
830
831 static inline void device_unlock(struct device *dev)
832 {
833 mutex_unlock(&dev->mutex);
834 }
835
836 void driver_init(void);
837
838 /*
839 * High level routines for use by the bus drivers
840 */
841 extern int __must_check device_register(struct device *dev);
842 extern void device_unregister(struct device *dev);
843 extern void device_initialize(struct device *dev);
844 extern int __must_check device_add(struct device *dev);
845 extern void device_del(struct device *dev);
846 extern int device_for_each_child(struct device *dev, void *data,
847 int (*fn)(struct device *dev, void *data));
848 extern struct device *device_find_child(struct device *dev, void *data,
849 int (*match)(struct device *dev, void *data));
850 extern int device_rename(struct device *dev, const char *new_name);
851 extern int device_move(struct device *dev, struct device *new_parent,
852 enum dpm_order dpm_order);
853 extern const char *device_get_devnode(struct device *dev,
854 umode_t *mode, kuid_t *uid, kgid_t *gid,
855 const char **tmp);
856 extern void *dev_get_drvdata(const struct device *dev);
857 extern int dev_set_drvdata(struct device *dev, void *data);
858
859 /*
860 * Root device objects for grouping under /sys/devices
861 */
862 extern struct device *__root_device_register(const char *name,
863 struct module *owner);
864
865 /*
866 * This is a macro to avoid include problems with THIS_MODULE,
867 * just as per what is done for device_schedule_callback() above.
868 */
869 #define root_device_register(name) \
870 __root_device_register(name, THIS_MODULE)
871
872 extern void root_device_unregister(struct device *root);
873
874 static inline void *dev_get_platdata(const struct device *dev)
875 {
876 return dev->platform_data;
877 }
878
879 /*
880 * Manual binding of a device to driver. See drivers/base/bus.c
881 * for information on use.
882 */
883 extern int __must_check device_bind_driver(struct device *dev);
884 extern void device_release_driver(struct device *dev);
885 extern int __must_check device_attach(struct device *dev);
886 extern int __must_check driver_attach(struct device_driver *drv);
887 extern int __must_check device_reprobe(struct device *dev);
888
889 /*
890 * Easy functions for dynamically creating devices on the fly
891 */
892 extern struct device *device_create_vargs(struct class *cls,
893 struct device *parent,
894 dev_t devt,
895 void *drvdata,
896 const char *fmt,
897 va_list vargs);
898 extern __printf(5, 6)
899 struct device *device_create(struct class *cls, struct device *parent,
900 dev_t devt, void *drvdata,
901 const char *fmt, ...);
902 extern void device_destroy(struct class *cls, dev_t devt);
903
904 /*
905 * Platform "fixup" functions - allow the platform to have their say
906 * about devices and actions that the general device layer doesn't
907 * know about.
908 */
909 /* Notify platform of device discovery */
910 extern int (*platform_notify)(struct device *dev);
911
912 extern int (*platform_notify_remove)(struct device *dev);
913
914
915 /*
916 * get_device - atomically increment the reference count for the device.
917 *
918 */
919 extern struct device *get_device(struct device *dev);
920 extern void put_device(struct device *dev);
921
922 #ifdef CONFIG_DEVTMPFS
923 extern int devtmpfs_create_node(struct device *dev);
924 extern int devtmpfs_delete_node(struct device *dev);
925 extern int devtmpfs_mount(const char *mntdir);
926 #else
927 static inline int devtmpfs_create_node(struct device *dev) { return 0; }
928 static inline int devtmpfs_delete_node(struct device *dev) { return 0; }
929 static inline int devtmpfs_mount(const char *mountpoint) { return 0; }
930 #endif
931
932 /* drivers/base/power/shutdown.c */
933 extern void device_shutdown(void);
934
935 /* debugging and troubleshooting/diagnostic helpers. */
936 extern const char *dev_driver_string(const struct device *dev);
937
938
939 #ifdef CONFIG_PRINTK
940
941 extern __printf(3, 0)
942 int dev_vprintk_emit(int level, const struct device *dev,
943 const char *fmt, va_list args);
944 extern __printf(3, 4)
945 int dev_printk_emit(int level, const struct device *dev, const char *fmt, ...);
946
947 extern __printf(3, 4)
948 int dev_printk(const char *level, const struct device *dev,
949 const char *fmt, ...);
950 extern __printf(2, 3)
951 int dev_emerg(const struct device *dev, const char *fmt, ...);
952 extern __printf(2, 3)
953 int dev_alert(const struct device *dev, const char *fmt, ...);
954 extern __printf(2, 3)
955 int dev_crit(const struct device *dev, const char *fmt, ...);
956 extern __printf(2, 3)
957 int dev_err(const struct device *dev, const char *fmt, ...);
958 extern __printf(2, 3)
959 int dev_warn(const struct device *dev, const char *fmt, ...);
960 extern __printf(2, 3)
961 int dev_notice(const struct device *dev, const char *fmt, ...);
962 extern __printf(2, 3)
963 int _dev_info(const struct device *dev, const char *fmt, ...);
964
965 #else
966
967 static inline __printf(3, 0)
968 int dev_vprintk_emit(int level, const struct device *dev,
969 const char *fmt, va_list args)
970 { return 0; }
971 static inline __printf(3, 4)
972 int dev_printk_emit(int level, const struct device *dev, const char *fmt, ...)
973 { return 0; }
974
975 static inline int __dev_printk(const char *level, const struct device *dev,
976 struct va_format *vaf)
977 { return 0; }
978 static inline __printf(3, 4)
979 int dev_printk(const char *level, const struct device *dev,
980 const char *fmt, ...)
981 { return 0; }
982
983 static inline __printf(2, 3)
984 int dev_emerg(const struct device *dev, const char *fmt, ...)
985 { return 0; }
986 static inline __printf(2, 3)
987 int dev_crit(const struct device *dev, const char *fmt, ...)
988 { return 0; }
989 static inline __printf(2, 3)
990 int dev_alert(const struct device *dev, const char *fmt, ...)
991 { return 0; }
992 static inline __printf(2, 3)
993 int dev_err(const struct device *dev, const char *fmt, ...)
994 { return 0; }
995 static inline __printf(2, 3)
996 int dev_warn(const struct device *dev, const char *fmt, ...)
997 { return 0; }
998 static inline __printf(2, 3)
999 int dev_notice(const struct device *dev, const char *fmt, ...)
1000 { return 0; }
1001 static inline __printf(2, 3)
1002 int _dev_info(const struct device *dev, const char *fmt, ...)
1003 { return 0; }
1004
1005 #endif
1006
1007 /*
1008 * Stupid hackaround for existing uses of non-printk uses dev_info
1009 *
1010 * Note that the definition of dev_info below is actually _dev_info
1011 * and a macro is used to avoid redefining dev_info
1012 */
1013
1014 #define dev_info(dev, fmt, arg...) _dev_info(dev, fmt, ##arg)
1015
1016 #if defined(CONFIG_DYNAMIC_DEBUG)
1017 #define dev_dbg(dev, format, ...) \
1018 do { \
1019 dynamic_dev_dbg(dev, format, ##__VA_ARGS__); \
1020 } while (0)
1021 #elif defined(DEBUG)
1022 #define dev_dbg(dev, format, arg...) \
1023 dev_printk(KERN_DEBUG, dev, format, ##arg)
1024 #else
1025 #define dev_dbg(dev, format, arg...) \
1026 ({ \
1027 if (0) \
1028 dev_printk(KERN_DEBUG, dev, format, ##arg); \
1029 0; \
1030 })
1031 #endif
1032
1033 #define dev_level_ratelimited(dev_level, dev, fmt, ...) \
1034 do { \
1035 static DEFINE_RATELIMIT_STATE(_rs, \
1036 DEFAULT_RATELIMIT_INTERVAL, \
1037 DEFAULT_RATELIMIT_BURST); \
1038 if (__ratelimit(&_rs)) \
1039 dev_level(dev, fmt, ##__VA_ARGS__); \
1040 } while (0)
1041
1042 #define dev_emerg_ratelimited(dev, fmt, ...) \
1043 dev_level_ratelimited(dev_emerg, dev, fmt, ##__VA_ARGS__)
1044 #define dev_alert_ratelimited(dev, fmt, ...) \
1045 dev_level_ratelimited(dev_alert, dev, fmt, ##__VA_ARGS__)
1046 #define dev_crit_ratelimited(dev, fmt, ...) \
1047 dev_level_ratelimited(dev_crit, dev, fmt, ##__VA_ARGS__)
1048 #define dev_err_ratelimited(dev, fmt, ...) \
1049 dev_level_ratelimited(dev_err, dev, fmt, ##__VA_ARGS__)
1050 #define dev_warn_ratelimited(dev, fmt, ...) \
1051 dev_level_ratelimited(dev_warn, dev, fmt, ##__VA_ARGS__)
1052 #define dev_notice_ratelimited(dev, fmt, ...) \
1053 dev_level_ratelimited(dev_notice, dev, fmt, ##__VA_ARGS__)
1054 #define dev_info_ratelimited(dev, fmt, ...) \
1055 dev_level_ratelimited(dev_info, dev, fmt, ##__VA_ARGS__)
1056 #if defined(CONFIG_DYNAMIC_DEBUG) || defined(DEBUG)
1057 #define dev_dbg_ratelimited(dev, fmt, ...) \
1058 do { \
1059 static DEFINE_RATELIMIT_STATE(_rs, \
1060 DEFAULT_RATELIMIT_INTERVAL, \
1061 DEFAULT_RATELIMIT_BURST); \
1062 DEFINE_DYNAMIC_DEBUG_METADATA(descriptor, fmt); \
1063 if (unlikely(descriptor.flags & _DPRINTK_FLAGS_PRINT) && \
1064 __ratelimit(&_rs)) \
1065 __dynamic_pr_debug(&descriptor, pr_fmt(fmt), \
1066 ##__VA_ARGS__); \
1067 } while (0)
1068 #else
1069 #define dev_dbg_ratelimited(dev, fmt, ...) \
1070 no_printk(KERN_DEBUG pr_fmt(fmt), ##__VA_ARGS__)
1071 #endif
1072
1073 #ifdef VERBOSE_DEBUG
1074 #define dev_vdbg dev_dbg
1075 #else
1076 #define dev_vdbg(dev, format, arg...) \
1077 ({ \
1078 if (0) \
1079 dev_printk(KERN_DEBUG, dev, format, ##arg); \
1080 0; \
1081 })
1082 #endif
1083
1084 /*
1085 * dev_WARN*() acts like dev_printk(), but with the key difference
1086 * of using a WARN/WARN_ON to get the message out, including the
1087 * file/line information and a backtrace.
1088 */
1089 #define dev_WARN(dev, format, arg...) \
1090 WARN(1, "Device: %s\n" format, dev_driver_string(dev), ## arg);
1091
1092 #define dev_WARN_ONCE(dev, condition, format, arg...) \
1093 WARN_ONCE(condition, "Device %s\n" format, \
1094 dev_driver_string(dev), ## arg)
1095
1096 /* Create alias, so I can be autoloaded. */
1097 #define MODULE_ALIAS_CHARDEV(major,minor) \
1098 MODULE_ALIAS("char-major-" __stringify(major) "-" __stringify(minor))
1099 #define MODULE_ALIAS_CHARDEV_MAJOR(major) \
1100 MODULE_ALIAS("char-major-" __stringify(major) "-*")
1101
1102 #ifdef CONFIG_SYSFS_DEPRECATED
1103 extern long sysfs_deprecated;
1104 #else
1105 #define sysfs_deprecated 0
1106 #endif
1107
1108 /**
1109 * module_driver() - Helper macro for drivers that don't do anything
1110 * special in module init/exit. This eliminates a lot of boilerplate.
1111 * Each module may only use this macro once, and calling it replaces
1112 * module_init() and module_exit().
1113 *
1114 * @__driver: driver name
1115 * @__register: register function for this driver type
1116 * @__unregister: unregister function for this driver type
1117 * @...: Additional arguments to be passed to __register and __unregister.
1118 *
1119 * Use this macro to construct bus specific macros for registering
1120 * drivers, and do not use it on its own.
1121 */
1122 #define module_driver(__driver, __register, __unregister, ...) \
1123 static int __init __driver##_init(void) \
1124 { \
1125 return __register(&(__driver) , ##__VA_ARGS__); \
1126 } \
1127 module_init(__driver##_init); \
1128 static void __exit __driver##_exit(void) \
1129 { \
1130 __unregister(&(__driver) , ##__VA_ARGS__); \
1131 } \
1132 module_exit(__driver##_exit);
1133
1134 #endif /* _DEVICE_H_ */
1135
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