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