1 /* 2 * device.h - generic, centralized driver model 3 * 4 * Copyright (c) 2001-2003 Patrick Mochel <[email protected]> 5 * Copyright (c) 2004-2009 Greg Kroah-Hartman <[email protected]> 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 <linux/ratelimit.h> 27 #include <asm/device.h> 28 29 struct device; 30 struct device_private; 31 struct device_driver; 32 struct driver_private; 33 struct module; 34 struct class; 35 struct subsys_private; 36 struct bus_type; 37 struct device_node; 38 struct iommu_ops; 39 struct iommu_group; 40 41 struct bus_attribute { 42 struct attribute attr; 43 ssize_t (*show)(struct bus_type *bus, char *buf); 44 ssize_t (*store)(struct bus_type *bus, const char *buf, size_t count); 45 }; 46 47 #define BUS_ATTR(_name, _mode, _show, _store) \ 48 struct bus_attribute bus_attr_##_name = __ATTR(_name, _mode, _show, _store) 49 50 extern int __must_check bus_create_file(struct bus_type *, 51 struct bus_attribute *); 52 extern void bus_remove_file(struct bus_type *, struct bus_attribute *); 53 54 /** 55 * struct bus_type - The bus type of the device 56 * 57 * @name: The name of the bus. 58 * @dev_name: Used for subsystems to enumerate devices like ("foo%u", dev->id). 59 * @dev_root: Default device to use as the parent. 60 * @bus_attrs: Default attributes of the bus. 61 * @dev_attrs: Default attributes of the devices on the bus. 62 * @drv_attrs: Default attributes of the device drivers on the bus. 63 * @match: Called, perhaps multiple times, whenever a new device or driver 64 * is added for this bus. It should return a nonzero value if the 65 * given device can be handled by the given driver. 66 * @uevent: Called when a device is added, removed, or a few other things 67 * that generate uevents to add the environment variables. 68 * @probe: Called when a new device or driver add to this bus, and callback 69 * the specific driver's probe to initial the matched device. 70 * @remove: Called when a device removed from this bus. 71 * @shutdown: Called at shut-down time to quiesce the device. 72 * @suspend: Called when a device on this bus wants to go to sleep mode. 73 * @resume: Called to bring a device on this bus out of sleep mode. 74 * @pm: Power management operations of this bus, callback the specific 75 * device driver's pm-ops. 76 * @iommu_ops: IOMMU specific operations for this bus, used to attach IOMMU 77 * driver implementations to a bus and allow the driver to do 78 * bus-specific setup 79 * @p: The private data of the driver core, only the driver core can 80 * touch this. 81 * 82 * A bus is a channel between the processor and one or more devices. For the 83 * purposes of the device model, all devices are connected via a bus, even if 84 * it is an internal, virtual, "platform" bus. Buses can plug into each other. 85 * A USB controller is usually a PCI device, for example. The device model 86 * represents the actual connections between buses and the devices they control. 87 * A bus is represented by the bus_type structure. It contains the name, the 88 * default attributes, the bus' methods, PM operations, and the driver core's 89 * private data. 90 */ 91 struct bus_type { 92 const char *name; 93 const char *dev_name; 94 struct device *dev_root; 95 struct bus_attribute *bus_attrs; 96 struct device_attribute *dev_attrs; 97 struct driver_attribute *drv_attrs; 98 99 int (*match)(struct device *dev, struct device_driver *drv); 100 int (*uevent)(struct device *dev, struct kobj_uevent_env *env); 101 int (*probe)(struct device *dev); 102 int (*remove)(struct device *dev); 103 void (*shutdown)(struct device *dev); 104 105 int (*suspend)(struct device *dev, pm_message_t state); 106 int (*resume)(struct device *dev); 107 108 const struct dev_pm_ops *pm; 109 110 struct iommu_ops *iommu_ops; 111 112 struct subsys_private *p; 113 }; 114 115 /* This is a #define to keep the compiler from merging different 116 * instances of the __key variable */ 117 #define bus_register(subsys) \ 118 ({ \ 119 static struct lock_class_key __key; \ 120 __bus_register(subsys, &__key); \ 121 }) 122 extern int __must_check __bus_register(struct bus_type *bus, 123 struct lock_class_key *key); 124 extern void bus_unregister(struct bus_type *bus); 125 126 extern int __must_check bus_rescan_devices(struct bus_type *bus); 127 128 /* iterator helpers for buses */ 129 struct subsys_dev_iter { 130 struct klist_iter ki; 131 const struct device_type *type; 132 }; 133 void subsys_dev_iter_init(struct subsys_dev_iter *iter, 134 struct bus_type *subsys, 135 struct device *start, 136 const struct device_type *type); 137 struct device *subsys_dev_iter_next(struct subsys_dev_iter *iter); 138 void subsys_dev_iter_exit(struct subsys_dev_iter *iter); 139 140 int bus_for_each_dev(struct bus_type *bus, struct device *start, void *data, 141 int (*fn)(struct device *dev, void *data)); 142 struct device *bus_find_device(struct bus_type *bus, struct device *start, 143 void *data, 144 int (*match)(struct device *dev, void *data)); 145 struct device *bus_find_device_by_name(struct bus_type *bus, 146 struct device *start, 147 const char *name); 148 struct device *subsys_find_device_by_id(struct bus_type *bus, unsigned int id, 149 struct device *hint); 150 int bus_for_each_drv(struct bus_type *bus, struct device_driver *start, 151 void *data, int (*fn)(struct device_driver *, void *)); 152 void bus_sort_breadthfirst(struct bus_type *bus, 153 int (*compare)(const struct device *a, 154 const struct device *b)); 155 /* 156 * Bus notifiers: Get notified of addition/removal of devices 157 * and binding/unbinding of drivers to devices. 158 * In the long run, it should be a replacement for the platform 159 * notify hooks. 160 */ 161 struct notifier_block; 162 163 extern int bus_register_notifier(struct bus_type *bus, 164 struct notifier_block *nb); 165 extern int bus_unregister_notifier(struct bus_type *bus, 166 struct notifier_block *nb); 167 168 /* All 4 notifers below get called with the target struct device * 169 * as an argument. Note that those functions are likely to be called 170 * with the device lock held in the core, so be careful. 171 */ 172 #define BUS_NOTIFY_ADD_DEVICE 0x00000001 /* device added */ 173 #define BUS_NOTIFY_DEL_DEVICE 0x00000002 /* device removed */ 174 #define BUS_NOTIFY_BIND_DRIVER 0x00000003 /* driver about to be 175 bound */ 176 #define BUS_NOTIFY_BOUND_DRIVER 0x00000004 /* driver bound to device */ 177 #define BUS_NOTIFY_UNBIND_DRIVER 0x00000005 /* driver about to be 178 unbound */ 179 #define BUS_NOTIFY_UNBOUND_DRIVER 0x00000006 /* driver is unbound 180 from the device */ 181 182 extern struct kset *bus_get_kset(struct bus_type *bus); 183 extern struct klist *bus_get_device_klist(struct bus_type *bus); 184 185 /** 186 * struct device_driver - The basic device driver structure 187 * @name: Name of the device driver. 188 * @bus: The bus which the device of this driver belongs to. 189 * @owner: The module owner. 190 * @mod_name: Used for built-in modules. 191 * @suppress_bind_attrs: Disables bind/unbind via sysfs. 192 * @of_match_table: The open firmware table. 193 * @probe: Called to query the existence of a specific device, 194 * whether this driver can work with it, and bind the driver 195 * to a specific device. 196 * @remove: Called when the device is removed from the system to 197 * unbind a device from this driver. 198 * @shutdown: Called at shut-down time to quiesce the device. 199 * @suspend: Called to put the device to sleep mode. Usually to a 200 * low power state. 201 * @resume: Called to bring a device from sleep mode. 202 * @groups: Default attributes that get created by the driver core 203 * automatically. 204 * @pm: Power management operations of the device which matched 205 * this driver. 206 * @p: Driver core's private data, no one other than the driver 207 * core can touch this. 208 * 209 * The device driver-model tracks all of the drivers known to the system. 210 * The main reason for this tracking is to enable the driver core to match 211 * up drivers with new devices. Once drivers are known objects within the 212 * system, however, a number of other things become possible. Device drivers 213 * can export information and configuration variables that are independent 214 * of any specific device. 215 */ 216 struct device_driver { 217 const char *name; 218 struct bus_type *bus; 219 220 struct module *owner; 221 const char *mod_name; /* used for built-in modules */ 222 223 bool suppress_bind_attrs; /* disables bind/unbind via sysfs */ 224 225 const struct of_device_id *of_match_table; 226 227 int (*probe) (struct device *dev); 228 int (*remove) (struct device *dev); 229 void (*shutdown) (struct device *dev); 230 int (*suspend) (struct device *dev, pm_message_t state); 231 int (*resume) (struct device *dev); 232 const struct attribute_group **groups; 233 234 const struct dev_pm_ops *pm; 235 236 struct driver_private *p; 237 }; 238 239 240 extern int __must_check driver_register(struct device_driver *drv); 241 extern void driver_unregister(struct device_driver *drv); 242 243 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_for_each_device(struct device_driver *drv, 268 struct device *start, 269 void *data, 270 int (*fn)(struct device *dev, 271 void *)); 272 struct device *driver_find_device(struct device_driver *drv, 273 struct device *start, void *data, 274 int (*match)(struct device *dev, void *data)); 275 276 /** 277 * struct subsys_interface - interfaces to device functions 278 * @name: name of the device function 279 * @subsys: subsytem of the devices to attach to 280 * @node: the list of functions registered at the subsystem 281 * @add_dev: device hookup to device function handler 282 * @remove_dev: device hookup to device function handler 283 * 284 * Simple interfaces attached to a subsystem. Multiple interfaces can 285 * attach to a subsystem and its devices. Unlike drivers, they do not 286 * exclusively claim or control devices. Interfaces usually represent 287 * a specific functionality of a subsystem/class of devices. 288 */ 289 struct subsys_interface { 290 const char *name; 291 struct bus_type *subsys; 292 struct list_head node; 293 int (*add_dev)(struct device *dev, struct subsys_interface *sif); 294 int (*remove_dev)(struct device *dev, struct subsys_interface *sif); 295 }; 296 297 int subsys_interface_register(struct subsys_interface *sif); 298 void subsys_interface_unregister(struct subsys_interface *sif); 299 300 int subsys_system_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, void *data, 397 int (*match)(struct device *, 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 void (*release)(struct device *dev); 473 474 const struct dev_pm_ops *pm; 475 }; 476 477 /* interface for exporting device attributes */ 478 struct device_attribute { 479 struct attribute attr; 480 ssize_t (*show)(struct device *dev, struct device_attribute *attr, 481 char *buf); 482 ssize_t (*store)(struct device *dev, struct device_attribute *attr, 483 const char *buf, size_t count); 484 }; 485 486 struct dev_ext_attribute { 487 struct device_attribute attr; 488 void *var; 489 }; 490 491 ssize_t device_show_ulong(struct device *dev, struct device_attribute *attr, 492 char *buf); 493 ssize_t device_store_ulong(struct device *dev, struct device_attribute *attr, 494 const char *buf, size_t count); 495 ssize_t device_show_int(struct device *dev, struct device_attribute *attr, 496 char *buf); 497 ssize_t device_store_int(struct device *dev, struct device_attribute *attr, 498 const char *buf, size_t count); 499 500 #define DEVICE_ATTR(_name, _mode, _show, _store) \ 501 struct device_attribute dev_attr_##_name = __ATTR(_name, _mode, _show, _store) 502 #define DEVICE_ULONG_ATTR(_name, _mode, _var) \ 503 struct dev_ext_attribute dev_attr_##_name = \ 504 { __ATTR(_name, _mode, device_show_ulong, device_store_ulong), &(_var) } 505 #define DEVICE_INT_ATTR(_name, _mode, _var) \ 506 struct dev_ext_attribute dev_attr_##_name = \ 507 { __ATTR(_name, _mode, device_show_int, device_store_int), &(_var) } 508 #define DEVICE_ATTR_IGNORE_LOCKDEP(_name, _mode, _show, _store) \ 509 struct device_attribute dev_attr_##_name = \ 510 __ATTR_IGNORE_LOCKDEP(_name, _mode, _show, _store) 511 512 extern int device_create_file(struct device *device, 513 const struct device_attribute *entry); 514 extern void device_remove_file(struct device *dev, 515 const struct device_attribute *attr); 516 extern int __must_check device_create_bin_file(struct device *dev, 517 const struct bin_attribute *attr); 518 extern void device_remove_bin_file(struct device *dev, 519 const struct bin_attribute *attr); 520 extern int device_schedule_callback_owner(struct device *dev, 521 void (*func)(struct device *dev), struct module *owner); 522 523 /* This is a macro to avoid include problems with THIS_MODULE */ 524 #define device_schedule_callback(dev, func) \ 525 device_schedule_callback_owner(dev, func, THIS_MODULE) 526 527 /* device resource management */ 528 typedef void (*dr_release_t)(struct device *dev, void *res); 529 typedef int (*dr_match_t)(struct device *dev, void *res, void *match_data); 530 531 #ifdef CONFIG_DEBUG_DEVRES 532 extern void *__devres_alloc(dr_release_t release, size_t size, gfp_t gfp, 533 const char *name); 534 #define devres_alloc(release, size, gfp) \ 535 __devres_alloc(release, size, gfp, #release) 536 #else 537 extern void *devres_alloc(dr_release_t release, size_t size, gfp_t gfp); 538 #endif 539 extern void devres_free(void *res); 540 extern void devres_add(struct device *dev, void *res); 541 extern void *devres_find(struct device *dev, dr_release_t release, 542 dr_match_t match, void *match_data); 543 extern void *devres_get(struct device *dev, void *new_res, 544 dr_match_t match, void *match_data); 545 extern void *devres_remove(struct device *dev, dr_release_t release, 546 dr_match_t match, void *match_data); 547 extern int devres_destroy(struct device *dev, dr_release_t release, 548 dr_match_t match, void *match_data); 549 extern int devres_release(struct device *dev, dr_release_t release, 550 dr_match_t match, void *match_data); 551 552 /* devres group */ 553 extern void * __must_check devres_open_group(struct device *dev, void *id, 554 gfp_t gfp); 555 extern void devres_close_group(struct device *dev, void *id); 556 extern void devres_remove_group(struct device *dev, void *id); 557 extern int devres_release_group(struct device *dev, void *id); 558 559 /* managed kzalloc/kfree for device drivers, no kmalloc, always use kzalloc */ 560 extern void *devm_kzalloc(struct device *dev, size_t size, gfp_t gfp); 561 extern void devm_kfree(struct device *dev, void *p); 562 563 void __iomem *devm_request_and_ioremap(struct device *dev, 564 struct resource *res); 565 566 struct device_dma_parameters { 567 /* 568 * a low level driver may set these to teach IOMMU code about 569 * sg limitations. 570 */ 571 unsigned int max_segment_size; 572 unsigned long segment_boundary_mask; 573 }; 574 575 /** 576 * struct device - The basic device structure 577 * @parent: The device's "parent" device, the device to which it is attached. 578 * In most cases, a parent device is some sort of bus or host 579 * controller. If parent is NULL, the device, is a top-level device, 580 * which is not usually what you want. 581 * @p: Holds the private data of the driver core portions of the device. 582 * See the comment of the struct device_private for detail. 583 * @kobj: A top-level, abstract class from which other classes are derived. 584 * @init_name: Initial name of the device. 585 * @type: The type of device. 586 * This identifies the device type and carries type-specific 587 * information. 588 * @mutex: Mutex to synchronize calls to its driver. 589 * @bus: Type of bus device is on. 590 * @driver: Which driver has allocated this 591 * @platform_data: Platform data specific to the device. 592 * Example: For devices on custom boards, as typical of embedded 593 * and SOC based hardware, Linux often uses platform_data to point 594 * to board-specific structures describing devices and how they 595 * are wired. That can include what ports are available, chip 596 * variants, which GPIO pins act in what additional roles, and so 597 * on. This shrinks the "Board Support Packages" (BSPs) and 598 * minimizes board-specific #ifdefs in drivers. 599 * @power: For device power management. 600 * See Documentation/power/devices.txt for details. 601 * @pm_domain: Provide callbacks that are executed during system suspend, 602 * hibernation, system resume and during runtime PM transitions 603 * along with subsystem-level and driver-level callbacks. 604 * @numa_node: NUMA node this device is close to. 605 * @dma_mask: Dma mask (if dma'ble device). 606 * @coherent_dma_mask: Like dma_mask, but for alloc_coherent mapping as not all 607 * hardware supports 64-bit addresses for consistent allocations 608 * such descriptors. 609 * @dma_parms: A low level driver may set these to teach IOMMU code about 610 * segment limitations. 611 * @dma_pools: Dma pools (if dma'ble device). 612 * @dma_mem: Internal for coherent mem override. 613 * @archdata: For arch-specific additions. 614 * @of_node: Associated device tree node. 615 * @devt: For creating the sysfs "dev". 616 * @id: device instance 617 * @devres_lock: Spinlock to protect the resource of the device. 618 * @devres_head: The resources list of the device. 619 * @knode_class: The node used to add the device to the class list. 620 * @class: The class of the device. 621 * @groups: Optional attribute groups. 622 * @release: Callback to free the device after all references have 623 * gone away. This should be set by the allocator of the 624 * device (i.e. the bus driver that discovered the device). 625 * 626 * At the lowest level, every device in a Linux system is represented by an 627 * instance of struct device. The device structure contains the information 628 * that the device model core needs to model the system. Most subsystems, 629 * however, track additional information about the devices they host. As a 630 * result, it is rare for devices to be represented by bare device structures; 631 * instead, that structure, like kobject structures, is usually embedded within 632 * a higher-level representation of the device. 633 */ 634 struct device { 635 struct device *parent; 636 637 struct device_private *p; 638 639 struct kobject kobj; 640 const char *init_name; /* initial name of the device */ 641 const struct device_type *type; 642 643 struct mutex mutex; /* mutex to synchronize calls to 644 * its driver. 645 */ 646 647 struct bus_type *bus; /* type of bus device is on */ 648 struct device_driver *driver; /* which driver has allocated this 649 device */ 650 void *platform_data; /* Platform specific data, device 651 core doesn't touch it */ 652 struct dev_pm_info power; 653 struct dev_pm_domain *pm_domain; 654 655 #ifdef CONFIG_NUMA 656 int numa_node; /* NUMA node this device is close to */ 657 #endif 658 u64 *dma_mask; /* dma mask (if dma'able device) */ 659 u64 coherent_dma_mask;/* Like dma_mask, but for 660 alloc_coherent mappings as 661 not all hardware supports 662 64 bit addresses for consistent 663 allocations such descriptors. */ 664 665 struct device_dma_parameters *dma_parms; 666 667 struct list_head dma_pools; /* dma pools (if dma'ble) */ 668 669 struct dma_coherent_mem *dma_mem; /* internal for coherent mem 670 override */ 671 #ifdef CONFIG_CMA 672 struct cma *cma_area; /* contiguous memory area for dma 673 allocations */ 674 #endif 675 /* arch specific additions */ 676 struct dev_archdata archdata; 677 678 struct device_node *of_node; /* associated device tree node */ 679 680 dev_t devt; /* dev_t, creates the sysfs "dev" */ 681 u32 id; /* device instance */ 682 683 spinlock_t devres_lock; 684 struct list_head devres_head; 685 686 struct klist_node knode_class; 687 struct class *class; 688 const struct attribute_group **groups; /* optional groups */ 689 690 void (*release)(struct device *dev); 691 struct iommu_group *iommu_group; 692 }; 693 694 static inline struct device *kobj_to_dev(struct kobject *kobj) 695 { 696 return container_of(kobj, struct device, kobj); 697 } 698 699 /* Get the wakeup routines, which depend on struct device */ 700 #include <linux/pm_wakeup.h> 701 702 static inline const char *dev_name(const struct device *dev) 703 { 704 /* Use the init name until the kobject becomes available */ 705 if (dev->init_name) 706 return dev->init_name; 707 708 return kobject_name(&dev->kobj); 709 } 710 711 extern __printf(2, 3) 712 int dev_set_name(struct device *dev, const char *name, ...); 713 714 #ifdef CONFIG_NUMA 715 static inline int dev_to_node(struct device *dev) 716 { 717 return dev->numa_node; 718 } 719 static inline void set_dev_node(struct device *dev, int node) 720 { 721 dev->numa_node = node; 722 } 723 #else 724 static inline int dev_to_node(struct device *dev) 725 { 726 return -1; 727 } 728 static inline void set_dev_node(struct device *dev, int node) 729 { 730 } 731 #endif 732 733 static inline struct pm_subsys_data *dev_to_psd(struct device *dev) 734 { 735 return dev ? dev->power.subsys_data : NULL; 736 } 737 738 static inline unsigned int dev_get_uevent_suppress(const struct device *dev) 739 { 740 return dev->kobj.uevent_suppress; 741 } 742 743 static inline void dev_set_uevent_suppress(struct device *dev, int val) 744 { 745 dev->kobj.uevent_suppress = val; 746 } 747 748 static inline int device_is_registered(struct device *dev) 749 { 750 return dev->kobj.state_in_sysfs; 751 } 752 753 static inline void device_enable_async_suspend(struct device *dev) 754 { 755 if (!dev->power.is_prepared) 756 dev->power.async_suspend = true; 757 } 758 759 static inline void device_disable_async_suspend(struct device *dev) 760 { 761 if (!dev->power.is_prepared) 762 dev->power.async_suspend = false; 763 } 764 765 static inline bool device_async_suspend_enabled(struct device *dev) 766 { 767 return !!dev->power.async_suspend; 768 } 769 770 static inline void pm_suspend_ignore_children(struct device *dev, bool enable) 771 { 772 dev->power.ignore_children = enable; 773 } 774 775 static inline void device_lock(struct device *dev) 776 { 777 mutex_lock(&dev->mutex); 778 } 779 780 static inline int device_trylock(struct device *dev) 781 { 782 return mutex_trylock(&dev->mutex); 783 } 784 785 static inline void device_unlock(struct device *dev) 786 { 787 mutex_unlock(&dev->mutex); 788 } 789 790 void driver_init(void); 791 792 /* 793 * High level routines for use by the bus drivers 794 */ 795 extern int __must_check device_register(struct device *dev); 796 extern void device_unregister(struct device *dev); 797 extern void device_initialize(struct device *dev); 798 extern int __must_check device_add(struct device *dev); 799 extern void device_del(struct device *dev); 800 extern int device_for_each_child(struct device *dev, void *data, 801 int (*fn)(struct device *dev, void *data)); 802 extern struct device *device_find_child(struct device *dev, void *data, 803 int (*match)(struct device *dev, void *data)); 804 extern int device_rename(struct device *dev, const char *new_name); 805 extern int device_move(struct device *dev, struct device *new_parent, 806 enum dpm_order dpm_order); 807 extern const char *device_get_devnode(struct device *dev, 808 umode_t *mode, const char **tmp); 809 extern void *dev_get_drvdata(const struct device *dev); 810 extern int dev_set_drvdata(struct device *dev, void *data); 811 812 /* 813 * Root device objects for grouping under /sys/devices 814 */ 815 extern struct device *__root_device_register(const char *name, 816 struct module *owner); 817 818 /* 819 * This is a macro to avoid include problems with THIS_MODULE, 820 * just as per what is done for device_schedule_callback() above. 821 */ 822 #define root_device_register(name) \ 823 __root_device_register(name, THIS_MODULE) 824 825 extern void root_device_unregister(struct device *root); 826 827 static inline void *dev_get_platdata(const struct device *dev) 828 { 829 return dev->platform_data; 830 } 831 832 /* 833 * Manual binding of a device to driver. See drivers/base/bus.c 834 * for information on use. 835 */ 836 extern int __must_check device_bind_driver(struct device *dev); 837 extern void device_release_driver(struct device *dev); 838 extern int __must_check device_attach(struct device *dev); 839 extern int __must_check driver_attach(struct device_driver *drv); 840 extern int __must_check device_reprobe(struct device *dev); 841 842 /* 843 * Easy functions for dynamically creating devices on the fly 844 */ 845 extern struct device *device_create_vargs(struct class *cls, 846 struct device *parent, 847 dev_t devt, 848 void *drvdata, 849 const char *fmt, 850 va_list vargs); 851 extern __printf(5, 6) 852 struct device *device_create(struct class *cls, struct device *parent, 853 dev_t devt, void *drvdata, 854 const char *fmt, ...); 855 extern void device_destroy(struct class *cls, dev_t devt); 856 857 /* 858 * Platform "fixup" functions - allow the platform to have their say 859 * about devices and actions that the general device layer doesn't 860 * know about. 861 */ 862 /* Notify platform of device discovery */ 863 extern int (*platform_notify)(struct device *dev); 864 865 extern int (*platform_notify_remove)(struct device *dev); 866 867 868 /* 869 * get_device - atomically increment the reference count for the device. 870 * 871 */ 872 extern struct device *get_device(struct device *dev); 873 extern void put_device(struct device *dev); 874 875 #ifdef CONFIG_DEVTMPFS 876 extern int devtmpfs_create_node(struct device *dev); 877 extern int devtmpfs_delete_node(struct device *dev); 878 extern int devtmpfs_mount(const char *mntdir); 879 #else 880 static inline int devtmpfs_create_node(struct device *dev) { return 0; } 881 static inline int devtmpfs_delete_node(struct device *dev) { return 0; } 882 static inline int devtmpfs_mount(const char *mountpoint) { return 0; } 883 #endif 884 885 /* drivers/base/power/shutdown.c */ 886 extern void device_shutdown(void); 887 888 /* debugging and troubleshooting/diagnostic helpers. */ 889 extern const char *dev_driver_string(const struct device *dev); 890 891 892 #ifdef CONFIG_PRINTK 893 894 extern int __dev_printk(const char *level, const struct device *dev, 895 struct va_format *vaf); 896 extern __printf(3, 4) 897 int dev_printk(const char *level, const struct device *dev, 898 const char *fmt, ...) 899 ; 900 extern __printf(2, 3) 901 int dev_emerg(const struct device *dev, const char *fmt, ...); 902 extern __printf(2, 3) 903 int dev_alert(const struct device *dev, const char *fmt, ...); 904 extern __printf(2, 3) 905 int dev_crit(const struct device *dev, const char *fmt, ...); 906 extern __printf(2, 3) 907 int dev_err(const struct device *dev, const char *fmt, ...); 908 extern __printf(2, 3) 909 int dev_warn(const struct device *dev, const char *fmt, ...); 910 extern __printf(2, 3) 911 int dev_notice(const struct device *dev, const char *fmt, ...); 912 extern __printf(2, 3) 913 int _dev_info(const struct device *dev, const char *fmt, ...); 914 915 #else 916 917 static inline int __dev_printk(const char *level, const struct device *dev, 918 struct va_format *vaf) 919 { return 0; } 920 static inline __printf(3, 4) 921 int dev_printk(const char *level, const struct device *dev, 922 const char *fmt, ...) 923 { return 0; } 924 925 static inline __printf(2, 3) 926 int dev_emerg(const struct device *dev, const char *fmt, ...) 927 { return 0; } 928 static inline __printf(2, 3) 929 int dev_crit(const struct device *dev, const char *fmt, ...) 930 { return 0; } 931 static inline __printf(2, 3) 932 int dev_alert(const struct device *dev, const char *fmt, ...) 933 { return 0; } 934 static inline __printf(2, 3) 935 int dev_err(const struct device *dev, const char *fmt, ...) 936 { return 0; } 937 static inline __printf(2, 3) 938 int dev_warn(const struct device *dev, const char *fmt, ...) 939 { return 0; } 940 static inline __printf(2, 3) 941 int dev_notice(const struct device *dev, const char *fmt, ...) 942 { return 0; } 943 static inline __printf(2, 3) 944 int _dev_info(const struct device *dev, const char *fmt, ...) 945 { return 0; } 946 947 #endif 948 949 #define dev_level_ratelimited(dev_level, dev, fmt, ...) \ 950 do { \ 951 static DEFINE_RATELIMIT_STATE(_rs, \ 952 DEFAULT_RATELIMIT_INTERVAL, \ 953 DEFAULT_RATELIMIT_BURST); \ 954 if (__ratelimit(&_rs)) \ 955 dev_level(dev, fmt, ##__VA_ARGS__); \ 956 } while (0) 957 958 #define dev_emerg_ratelimited(dev, fmt, ...) \ 959 dev_level_ratelimited(dev_emerg, dev, fmt, ##__VA_ARGS__) 960 #define dev_alert_ratelimited(dev, fmt, ...) \ 961 dev_level_ratelimited(dev_alert, dev, fmt, ##__VA_ARGS__) 962 #define dev_crit_ratelimited(dev, fmt, ...) \ 963 dev_level_ratelimited(dev_crit, dev, fmt, ##__VA_ARGS__) 964 #define dev_err_ratelimited(dev, fmt, ...) \ 965 dev_level_ratelimited(dev_err, dev, fmt, ##__VA_ARGS__) 966 #define dev_warn_ratelimited(dev, fmt, ...) \ 967 dev_level_ratelimited(dev_warn, dev, fmt, ##__VA_ARGS__) 968 #define dev_notice_ratelimited(dev, fmt, ...) \ 969 dev_level_ratelimited(dev_notice, dev, fmt, ##__VA_ARGS__) 970 #define dev_info_ratelimited(dev, fmt, ...) \ 971 dev_level_ratelimited(dev_info, dev, fmt, ##__VA_ARGS__) 972 #define dev_dbg_ratelimited(dev, fmt, ...) \ 973 dev_level_ratelimited(dev_dbg, dev, fmt, ##__VA_ARGS__) 974 975 /* 976 * Stupid hackaround for existing uses of non-printk uses dev_info 977 * 978 * Note that the definition of dev_info below is actually _dev_info 979 * and a macro is used to avoid redefining dev_info 980 */ 981 982 #define dev_info(dev, fmt, arg...) _dev_info(dev, fmt, ##arg) 983 984 #if defined(CONFIG_DYNAMIC_DEBUG) 985 #define dev_dbg(dev, format, ...) \ 986 do { \ 987 dynamic_dev_dbg(dev, format, ##__VA_ARGS__); \ 988 } while (0) 989 #elif defined(DEBUG) 990 #define dev_dbg(dev, format, arg...) \ 991 dev_printk(KERN_DEBUG, dev, format, ##arg) 992 #else 993 #define dev_dbg(dev, format, arg...) \ 994 ({ \ 995 if (0) \ 996 dev_printk(KERN_DEBUG, dev, format, ##arg); \ 997 0; \ 998 }) 999 #endif 1000 1001 #ifdef VERBOSE_DEBUG 1002 #define dev_vdbg dev_dbg 1003 #else 1004 #define dev_vdbg(dev, format, arg...) \ 1005 ({ \ 1006 if (0) \ 1007 dev_printk(KERN_DEBUG, dev, format, ##arg); \ 1008 0; \ 1009 }) 1010 #endif 1011 1012 /* 1013 * dev_WARN*() acts like dev_printk(), but with the key difference 1014 * of using a WARN/WARN_ON to get the message out, including the 1015 * file/line information and a backtrace. 1016 */ 1017 #define dev_WARN(dev, format, arg...) \ 1018 WARN(1, "Device: %s\n" format, dev_driver_string(dev), ## arg); 1019 1020 #define dev_WARN_ONCE(dev, condition, format, arg...) \ 1021 WARN_ONCE(condition, "Device %s\n" format, \ 1022 dev_driver_string(dev), ## arg) 1023 1024 /* Create alias, so I can be autoloaded. */ 1025 #define MODULE_ALIAS_CHARDEV(major,minor) \ 1026 MODULE_ALIAS("char-major-" __stringify(major) "-" __stringify(minor)) 1027 #define MODULE_ALIAS_CHARDEV_MAJOR(major) \ 1028 MODULE_ALIAS("char-major-" __stringify(major) "-*") 1029 1030 #ifdef CONFIG_SYSFS_DEPRECATED 1031 extern long sysfs_deprecated; 1032 #else 1033 #define sysfs_deprecated 0 1034 #endif 1035 1036 /** 1037 * module_driver() - Helper macro for drivers that don't do anything 1038 * special in module init/exit. This eliminates a lot of boilerplate. 1039 * Each module may only use this macro once, and calling it replaces 1040 * module_init() and module_exit(). 1041 * 1042 * @__driver: driver name 1043 * @__register: register function for this driver type 1044 * @__unregister: unregister function for this driver type 1045 * @...: Additional arguments to be passed to __register and __unregister. 1046 * 1047 * Use this macro to construct bus specific macros for registering 1048 * drivers, and do not use it on its own. 1049 */ 1050 #define module_driver(__driver, __register, __unregister, ...) \ 1051 static int __init __driver##_init(void) \ 1052 { \ 1053 return __register(&(__driver) , ##__VA_ARGS__); \ 1054 } \ 1055 module_init(__driver##_init); \ 1056 static void __exit __driver##_exit(void) \ 1057 { \ 1058 __unregister(&(__driver) , ##__VA_ARGS__); \ 1059 } \ 1060 module_exit(__driver##_exit); 1061 1062 #endif /* _DEVICE_H_ */ 1063