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/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 <linux/gfp.h> 30 #include <asm/device.h> 31 32 struct device; 33 struct device_private; 34 struct device_driver; 35 struct driver_private; 36 struct module; 37 struct class; 38 struct subsys_private; 39 struct bus_type; 40 struct device_node; 41 struct iommu_ops; 42 struct iommu_group; 43 44 struct bus_attribute { 45 struct attribute attr; 46 ssize_t (*show)(struct bus_type *bus, char *buf); 47 ssize_t (*store)(struct bus_type *bus, const char *buf, size_t count); 48 }; 49 50 #define BUS_ATTR(_name, _mode, _show, _store) \ 51 struct bus_attribute bus_attr_##_name = __ATTR(_name, _mode, _show, _store) 52 #define BUS_ATTR_RW(_name) \ 53 struct bus_attribute bus_attr_##_name = __ATTR_RW(_name) 54 #define BUS_ATTR_RO(_name) \ 55 struct bus_attribute bus_attr_##_name = __ATTR_RO(_name) 56 57 extern int __must_check bus_create_file(struct bus_type *, 58 struct bus_attribute *); 59 extern void bus_remove_file(struct bus_type *, struct bus_attribute *); 60 61 /** 62 * struct bus_type - The bus type of the device 63 * 64 * @name: The name of the bus. 65 * @dev_name: Used for subsystems to enumerate devices like ("foo%u", dev->id). 66 * @dev_root: Default device to use as the parent. 67 * @dev_attrs: Default attributes of the devices on the bus. 68 * @bus_groups: Default attributes of the bus. 69 * @dev_groups: Default attributes of the devices on the bus. 70 * @drv_groups: Default attributes of the device drivers on the bus. 71 * @match: Called, perhaps multiple times, whenever a new device or driver 72 * is added for this bus. It should return a nonzero value if the 73 * given device can be handled by the given driver. 74 * @uevent: Called when a device is added, removed, or a few other things 75 * that generate uevents to add the environment variables. 76 * @probe: Called when a new device or driver add to this bus, and callback 77 * the specific driver's probe to initial the matched device. 78 * @remove: Called when a device removed from this bus. 79 * @shutdown: Called at shut-down time to quiesce the device. 80 * 81 * @online: Called to put the device back online (after offlining it). 82 * @offline: Called to put the device offline for hot-removal. May fail. 83 * 84 * @suspend: Called when a device on this bus wants to go to sleep mode. 85 * @resume: Called to bring a device on this bus out of sleep mode. 86 * @pm: Power management operations of this bus, callback the specific 87 * device driver's pm-ops. 88 * @iommu_ops: IOMMU specific operations for this bus, used to attach IOMMU 89 * driver implementations to a bus and allow the driver to do 90 * bus-specific setup 91 * @p: The private data of the driver core, only the driver core can 92 * touch this. 93 * @lock_key: Lock class key for use by the lock validator 94 * 95 * A bus is a channel between the processor and one or more devices. For the 96 * purposes of the device model, all devices are connected via a bus, even if 97 * it is an internal, virtual, "platform" bus. Buses can plug into each other. 98 * A USB controller is usually a PCI device, for example. The device model 99 * represents the actual connections between buses and the devices they control. 100 * A bus is represented by the bus_type structure. It contains the name, the 101 * default attributes, the bus' methods, PM operations, and the driver core's 102 * private data. 103 */ 104 struct bus_type { 105 const char *name; 106 const char *dev_name; 107 struct device *dev_root; 108 struct device_attribute *dev_attrs; /* use dev_groups instead */ 109 const struct attribute_group **bus_groups; 110 const struct attribute_group **dev_groups; 111 const struct attribute_group **drv_groups; 112 113 int (*match)(struct device *dev, struct device_driver *drv); 114 int (*uevent)(struct device *dev, struct kobj_uevent_env *env); 115 int (*probe)(struct device *dev); 116 int (*remove)(struct device *dev); 117 void (*shutdown)(struct device *dev); 118 119 int (*online)(struct device *dev); 120 int (*offline)(struct device *dev); 121 122 int (*suspend)(struct device *dev, pm_message_t state); 123 int (*resume)(struct device *dev); 124 125 const struct dev_pm_ops *pm; 126 127 struct iommu_ops *iommu_ops; 128 129 struct subsys_private *p; 130 struct lock_class_key lock_key; 131 }; 132 133 extern int __must_check bus_register(struct bus_type *bus); 134 135 extern void bus_unregister(struct bus_type *bus); 136 137 extern int __must_check bus_rescan_devices(struct bus_type *bus); 138 139 /* iterator helpers for buses */ 140 struct subsys_dev_iter { 141 struct klist_iter ki; 142 const struct device_type *type; 143 }; 144 void subsys_dev_iter_init(struct subsys_dev_iter *iter, 145 struct bus_type *subsys, 146 struct device *start, 147 const struct device_type *type); 148 struct device *subsys_dev_iter_next(struct subsys_dev_iter *iter); 149 void subsys_dev_iter_exit(struct subsys_dev_iter *iter); 150 151 int bus_for_each_dev(struct bus_type *bus, struct device *start, void *data, 152 int (*fn)(struct device *dev, void *data)); 153 struct device *bus_find_device(struct bus_type *bus, struct device *start, 154 void *data, 155 int (*match)(struct device *dev, void *data)); 156 struct device *bus_find_device_by_name(struct bus_type *bus, 157 struct device *start, 158 const char *name); 159 struct device *subsys_find_device_by_id(struct bus_type *bus, unsigned int id, 160 struct device *hint); 161 int bus_for_each_drv(struct bus_type *bus, struct device_driver *start, 162 void *data, int (*fn)(struct device_driver *, void *)); 163 void bus_sort_breadthfirst(struct bus_type *bus, 164 int (*compare)(const struct device *a, 165 const struct device *b)); 166 /* 167 * Bus notifiers: Get notified of addition/removal of devices 168 * and binding/unbinding of drivers to devices. 169 * In the long run, it should be a replacement for the platform 170 * notify hooks. 171 */ 172 struct notifier_block; 173 174 extern int bus_register_notifier(struct bus_type *bus, 175 struct notifier_block *nb); 176 extern int bus_unregister_notifier(struct bus_type *bus, 177 struct notifier_block *nb); 178 179 /* All 4 notifers below get called with the target struct device * 180 * as an argument. Note that those functions are likely to be called 181 * with the device lock held in the core, so be careful. 182 */ 183 #define BUS_NOTIFY_ADD_DEVICE 0x00000001 /* device added */ 184 #define BUS_NOTIFY_DEL_DEVICE 0x00000002 /* device removed */ 185 #define BUS_NOTIFY_BIND_DRIVER 0x00000003 /* driver about to be 186 bound */ 187 #define BUS_NOTIFY_BOUND_DRIVER 0x00000004 /* driver bound to device */ 188 #define BUS_NOTIFY_UNBIND_DRIVER 0x00000005 /* driver about to be 189 unbound */ 190 #define BUS_NOTIFY_UNBOUND_DRIVER 0x00000006 /* driver is unbound 191 from the device */ 192 193 extern struct kset *bus_get_kset(struct bus_type *bus); 194 extern struct klist *bus_get_device_klist(struct bus_type *bus); 195 196 /** 197 * struct device_driver - The basic device driver structure 198 * @name: Name of the device driver. 199 * @bus: The bus which the device of this driver belongs to. 200 * @owner: The module owner. 201 * @mod_name: Used for built-in modules. 202 * @suppress_bind_attrs: Disables bind/unbind via sysfs. 203 * @of_match_table: The open firmware table. 204 * @acpi_match_table: The ACPI match table. 205 * @probe: Called to query the existence of a specific device, 206 * whether this driver can work with it, and bind the driver 207 * to a specific device. 208 * @remove: Called when the device is removed from the system to 209 * unbind a device from this driver. 210 * @shutdown: Called at shut-down time to quiesce the device. 211 * @suspend: Called to put the device to sleep mode. Usually to a 212 * low power state. 213 * @resume: Called to bring a device from sleep mode. 214 * @groups: Default attributes that get created by the driver core 215 * automatically. 216 * @pm: Power management operations of the device which matched 217 * this driver. 218 * @p: Driver core's private data, no one other than the driver 219 * core can touch this. 220 * 221 * The device driver-model tracks all of the drivers known to the system. 222 * The main reason for this tracking is to enable the driver core to match 223 * up drivers with new devices. Once drivers are known objects within the 224 * system, however, a number of other things become possible. Device drivers 225 * can export information and configuration variables that are independent 226 * of any specific device. 227 */ 228 struct device_driver { 229 const char *name; 230 struct bus_type *bus; 231 232 struct module *owner; 233 const char *mod_name; /* used for built-in modules */ 234 235 bool suppress_bind_attrs; /* disables bind/unbind via sysfs */ 236 237 const struct of_device_id *of_match_table; 238 const struct acpi_device_id *acpi_match_table; 239 240 int (*probe) (struct device *dev); 241 int (*remove) (struct device *dev); 242 void (*shutdown) (struct device *dev); 243 int (*suspend) (struct device *dev, pm_message_t state); 244 int (*resume) (struct device *dev); 245 const struct attribute_group **groups; 246 247 const struct dev_pm_ops *pm; 248 249 struct driver_private *p; 250 }; 251 252 253 extern int __must_check driver_register(struct device_driver *drv); 254 extern void driver_unregister(struct device_driver *drv); 255 256 extern struct device_driver *driver_find(const char *name, 257 struct bus_type *bus); 258 extern int driver_probe_done(void); 259 extern void wait_for_device_probe(void); 260 261 262 /* sysfs interface for exporting driver attributes */ 263 264 struct driver_attribute { 265 struct attribute attr; 266 ssize_t (*show)(struct device_driver *driver, char *buf); 267 ssize_t (*store)(struct device_driver *driver, const char *buf, 268 size_t count); 269 }; 270 271 #define DRIVER_ATTR(_name, _mode, _show, _store) \ 272 struct driver_attribute driver_attr_##_name = __ATTR(_name, _mode, _show, _store) 273 #define DRIVER_ATTR_RW(_name) \ 274 struct driver_attribute driver_attr_##_name = __ATTR_RW(_name) 275 #define DRIVER_ATTR_RO(_name) \ 276 struct driver_attribute driver_attr_##_name = __ATTR_RO(_name) 277 #define DRIVER_ATTR_WO(_name) \ 278 struct driver_attribute driver_attr_##_name = __ATTR_WO(_name) 279 280 extern int __must_check driver_create_file(struct device_driver *driver, 281 const struct driver_attribute *attr); 282 extern void driver_remove_file(struct device_driver *driver, 283 const struct driver_attribute *attr); 284 285 extern int __must_check driver_for_each_device(struct device_driver *drv, 286 struct device *start, 287 void *data, 288 int (*fn)(struct device *dev, 289 void *)); 290 struct device *driver_find_device(struct device_driver *drv, 291 struct device *start, void *data, 292 int (*match)(struct device *dev, void *data)); 293 294 /** 295 * struct subsys_interface - interfaces to device functions 296 * @name: name of the device function 297 * @subsys: subsytem of the devices to attach to 298 * @node: the list of functions registered at the subsystem 299 * @add_dev: device hookup to device function handler 300 * @remove_dev: device hookup to device function handler 301 * 302 * Simple interfaces attached to a subsystem. Multiple interfaces can 303 * attach to a subsystem and its devices. Unlike drivers, they do not 304 * exclusively claim or control devices. Interfaces usually represent 305 * a specific functionality of a subsystem/class of devices. 306 */ 307 struct subsys_interface { 308 const char *name; 309 struct bus_type *subsys; 310 struct list_head node; 311 int (*add_dev)(struct device *dev, struct subsys_interface *sif); 312 int (*remove_dev)(struct device *dev, struct subsys_interface *sif); 313 }; 314 315 int subsys_interface_register(struct subsys_interface *sif); 316 void subsys_interface_unregister(struct subsys_interface *sif); 317 318 int subsys_system_register(struct bus_type *subsys, 319 const struct attribute_group **groups); 320 int subsys_virtual_register(struct bus_type *subsys, 321 const struct attribute_group **groups); 322 323 /** 324 * struct class - device classes 325 * @name: Name of the class. 326 * @owner: The module owner. 327 * @class_attrs: Default attributes of this class. 328 * @dev_groups: Default attributes of the devices that belong to the class. 329 * @dev_kobj: The kobject that represents this class and links it into the hierarchy. 330 * @dev_uevent: Called when a device is added, removed from this class, or a 331 * few other things that generate uevents to add the environment 332 * variables. 333 * @devnode: Callback to provide the devtmpfs. 334 * @class_release: Called to release this class. 335 * @dev_release: Called to release the device. 336 * @suspend: Used to put the device to sleep mode, usually to a low power 337 * state. 338 * @resume: Used to bring the device from the sleep mode. 339 * @ns_type: Callbacks so sysfs can detemine namespaces. 340 * @namespace: Namespace of the device belongs to this class. 341 * @pm: The default device power management operations of this class. 342 * @p: The private data of the driver core, no one other than the 343 * driver core can touch this. 344 * 345 * A class is a higher-level view of a device that abstracts out low-level 346 * implementation details. Drivers may see a SCSI disk or an ATA disk, but, 347 * at the class level, they are all simply disks. Classes allow user space 348 * to work with devices based on what they do, rather than how they are 349 * connected or how they work. 350 */ 351 struct class { 352 const char *name; 353 struct module *owner; 354 355 struct class_attribute *class_attrs; 356 const struct attribute_group **dev_groups; 357 struct kobject *dev_kobj; 358 359 int (*dev_uevent)(struct device *dev, struct kobj_uevent_env *env); 360 char *(*devnode)(struct device *dev, umode_t *mode); 361 362 void (*class_release)(struct class *class); 363 void (*dev_release)(struct device *dev); 364 365 int (*suspend)(struct device *dev, pm_message_t state); 366 int (*resume)(struct device *dev); 367 368 const struct kobj_ns_type_operations *ns_type; 369 const void *(*namespace)(struct device *dev); 370 371 const struct dev_pm_ops *pm; 372 373 struct subsys_private *p; 374 }; 375 376 struct class_dev_iter { 377 struct klist_iter ki; 378 const struct device_type *type; 379 }; 380 381 extern struct kobject *sysfs_dev_block_kobj; 382 extern struct kobject *sysfs_dev_char_kobj; 383 extern int __must_check __class_register(struct class *class, 384 struct lock_class_key *key); 385 extern void class_unregister(struct class *class); 386 387 /* This is a #define to keep the compiler from merging different 388 * instances of the __key variable */ 389 #define class_register(class) \ 390 ({ \ 391 static struct lock_class_key __key; \ 392 __class_register(class, &__key); \ 393 }) 394 395 struct class_compat; 396 struct class_compat *class_compat_register(const char *name); 397 void class_compat_unregister(struct class_compat *cls); 398 int class_compat_create_link(struct class_compat *cls, struct device *dev, 399 struct device *device_link); 400 void class_compat_remove_link(struct class_compat *cls, struct device *dev, 401 struct device *device_link); 402 403 extern void class_dev_iter_init(struct class_dev_iter *iter, 404 struct class *class, 405 struct device *start, 406 const struct device_type *type); 407 extern struct device *class_dev_iter_next(struct class_dev_iter *iter); 408 extern void class_dev_iter_exit(struct class_dev_iter *iter); 409 410 extern int class_for_each_device(struct class *class, struct device *start, 411 void *data, 412 int (*fn)(struct device *dev, void *data)); 413 extern struct device *class_find_device(struct class *class, 414 struct device *start, const void *data, 415 int (*match)(struct device *, const void *)); 416 417 struct class_attribute { 418 struct attribute attr; 419 ssize_t (*show)(struct class *class, struct class_attribute *attr, 420 char *buf); 421 ssize_t (*store)(struct class *class, struct class_attribute *attr, 422 const char *buf, size_t count); 423 }; 424 425 #define CLASS_ATTR(_name, _mode, _show, _store) \ 426 struct class_attribute class_attr_##_name = __ATTR(_name, _mode, _show, _store) 427 #define CLASS_ATTR_RW(_name) \ 428 struct class_attribute class_attr_##_name = __ATTR_RW(_name) 429 #define CLASS_ATTR_RO(_name) \ 430 struct class_attribute class_attr_##_name = __ATTR_RO(_name) 431 432 extern int __must_check class_create_file_ns(struct class *class, 433 const struct class_attribute *attr, 434 const void *ns); 435 extern void class_remove_file_ns(struct class *class, 436 const struct class_attribute *attr, 437 const void *ns); 438 439 static inline int __must_check class_create_file(struct class *class, 440 const struct class_attribute *attr) 441 { 442 return class_create_file_ns(class, attr, NULL); 443 } 444 445 static inline void class_remove_file(struct class *class, 446 const struct class_attribute *attr) 447 { 448 return class_remove_file_ns(class, attr, NULL); 449 } 450 451 /* Simple class attribute that is just a static string */ 452 struct class_attribute_string { 453 struct class_attribute attr; 454 char *str; 455 }; 456 457 /* Currently read-only only */ 458 #define _CLASS_ATTR_STRING(_name, _mode, _str) \ 459 { __ATTR(_name, _mode, show_class_attr_string, NULL), _str } 460 #define CLASS_ATTR_STRING(_name, _mode, _str) \ 461 struct class_attribute_string class_attr_##_name = \ 462 _CLASS_ATTR_STRING(_name, _mode, _str) 463 464 extern ssize_t show_class_attr_string(struct class *class, struct class_attribute *attr, 465 char *buf); 466 467 struct class_interface { 468 struct list_head node; 469 struct class *class; 470 471 int (*add_dev) (struct device *, struct class_interface *); 472 void (*remove_dev) (struct device *, struct class_interface *); 473 }; 474 475 extern int __must_check class_interface_register(struct class_interface *); 476 extern void class_interface_unregister(struct class_interface *); 477 478 extern struct class * __must_check __class_create(struct module *owner, 479 const char *name, 480 struct lock_class_key *key); 481 extern void class_destroy(struct class *cls); 482 483 /* This is a #define to keep the compiler from merging different 484 * instances of the __key variable */ 485 #define class_create(owner, name) \ 486 ({ \ 487 static struct lock_class_key __key; \ 488 __class_create(owner, name, &__key); \ 489 }) 490 491 /* 492 * The type of device, "struct device" is embedded in. A class 493 * or bus can contain devices of different types 494 * like "partitions" and "disks", "mouse" and "event". 495 * This identifies the device type and carries type-specific 496 * information, equivalent to the kobj_type of a kobject. 497 * If "name" is specified, the uevent will contain it in 498 * the DEVTYPE variable. 499 */ 500 struct device_type { 501 const char *name; 502 const struct attribute_group **groups; 503 int (*uevent)(struct device *dev, struct kobj_uevent_env *env); 504 char *(*devnode)(struct device *dev, umode_t *mode, 505 kuid_t *uid, kgid_t *gid); 506 void (*release)(struct device *dev); 507 508 const struct dev_pm_ops *pm; 509 }; 510 511 /* interface for exporting device attributes */ 512 struct device_attribute { 513 struct attribute attr; 514 ssize_t (*show)(struct device *dev, struct device_attribute *attr, 515 char *buf); 516 ssize_t (*store)(struct device *dev, struct device_attribute *attr, 517 const char *buf, size_t count); 518 }; 519 520 struct dev_ext_attribute { 521 struct device_attribute attr; 522 void *var; 523 }; 524 525 ssize_t device_show_ulong(struct device *dev, struct device_attribute *attr, 526 char *buf); 527 ssize_t device_store_ulong(struct device *dev, struct device_attribute *attr, 528 const char *buf, size_t count); 529 ssize_t device_show_int(struct device *dev, struct device_attribute *attr, 530 char *buf); 531 ssize_t device_store_int(struct device *dev, struct device_attribute *attr, 532 const char *buf, size_t count); 533 ssize_t device_show_bool(struct device *dev, struct device_attribute *attr, 534 char *buf); 535 ssize_t device_store_bool(struct device *dev, struct device_attribute *attr, 536 const char *buf, size_t count); 537 538 #define DEVICE_ATTR(_name, _mode, _show, _store) \ 539 struct device_attribute dev_attr_##_name = __ATTR(_name, _mode, _show, _store) 540 #define DEVICE_ATTR_RW(_name) \ 541 struct device_attribute dev_attr_##_name = __ATTR_RW(_name) 542 #define DEVICE_ATTR_RO(_name) \ 543 struct device_attribute dev_attr_##_name = __ATTR_RO(_name) 544 #define DEVICE_ATTR_WO(_name) \ 545 struct device_attribute dev_attr_##_name = __ATTR_WO(_name) 546 #define DEVICE_ULONG_ATTR(_name, _mode, _var) \ 547 struct dev_ext_attribute dev_attr_##_name = \ 548 { __ATTR(_name, _mode, device_show_ulong, device_store_ulong), &(_var) } 549 #define DEVICE_INT_ATTR(_name, _mode, _var) \ 550 struct dev_ext_attribute dev_attr_##_name = \ 551 { __ATTR(_name, _mode, device_show_int, device_store_int), &(_var) } 552 #define DEVICE_BOOL_ATTR(_name, _mode, _var) \ 553 struct dev_ext_attribute dev_attr_##_name = \ 554 { __ATTR(_name, _mode, device_show_bool, device_store_bool), &(_var) } 555 #define DEVICE_ATTR_IGNORE_LOCKDEP(_name, _mode, _show, _store) \ 556 struct device_attribute dev_attr_##_name = \ 557 __ATTR_IGNORE_LOCKDEP(_name, _mode, _show, _store) 558 559 extern int device_create_file(struct device *device, 560 const struct device_attribute *entry); 561 extern void device_remove_file(struct device *dev, 562 const struct device_attribute *attr); 563 extern int __must_check device_create_bin_file(struct device *dev, 564 const struct bin_attribute *attr); 565 extern void device_remove_bin_file(struct device *dev, 566 const struct bin_attribute *attr); 567 extern int device_schedule_callback_owner(struct device *dev, 568 void (*func)(struct device *dev), struct module *owner); 569 570 /* This is a macro to avoid include problems with THIS_MODULE */ 571 #define device_schedule_callback(dev, func) \ 572 device_schedule_callback_owner(dev, func, THIS_MODULE) 573 574 /* device resource management */ 575 typedef void (*dr_release_t)(struct device *dev, void *res); 576 typedef int (*dr_match_t)(struct device *dev, void *res, void *match_data); 577 578 #ifdef CONFIG_DEBUG_DEVRES 579 extern void *__devres_alloc(dr_release_t release, size_t size, gfp_t gfp, 580 const char *name); 581 #define devres_alloc(release, size, gfp) \ 582 __devres_alloc(release, size, gfp, #release) 583 #else 584 extern void *devres_alloc(dr_release_t release, size_t size, gfp_t gfp); 585 #endif 586 extern void devres_for_each_res(struct device *dev, dr_release_t release, 587 dr_match_t match, void *match_data, 588 void (*fn)(struct device *, void *, void *), 589 void *data); 590 extern void devres_free(void *res); 591 extern void devres_add(struct device *dev, void *res); 592 extern void *devres_find(struct device *dev, dr_release_t release, 593 dr_match_t match, void *match_data); 594 extern void *devres_get(struct device *dev, void *new_res, 595 dr_match_t match, void *match_data); 596 extern void *devres_remove(struct device *dev, dr_release_t release, 597 dr_match_t match, void *match_data); 598 extern int devres_destroy(struct device *dev, dr_release_t release, 599 dr_match_t match, void *match_data); 600 extern int devres_release(struct device *dev, dr_release_t release, 601 dr_match_t match, void *match_data); 602 603 /* devres group */ 604 extern void * __must_check devres_open_group(struct device *dev, void *id, 605 gfp_t gfp); 606 extern void devres_close_group(struct device *dev, void *id); 607 extern void devres_remove_group(struct device *dev, void *id); 608 extern int devres_release_group(struct device *dev, void *id); 609 610 /* managed devm_k.alloc/kfree for device drivers */ 611 extern void *devm_kmalloc(struct device *dev, size_t size, gfp_t gfp); 612 static inline void *devm_kzalloc(struct device *dev, size_t size, gfp_t gfp) 613 { 614 return devm_kmalloc(dev, size, gfp | __GFP_ZERO); 615 } 616 static inline void *devm_kmalloc_array(struct device *dev, 617 size_t n, size_t size, gfp_t flags) 618 { 619 if (size != 0 && n > SIZE_MAX / size) 620 return NULL; 621 return devm_kmalloc(dev, n * size, flags); 622 } 623 static inline void *devm_kcalloc(struct device *dev, 624 size_t n, size_t size, gfp_t flags) 625 { 626 return devm_kmalloc_array(dev, n, size, flags | __GFP_ZERO); 627 } 628 extern void devm_kfree(struct device *dev, void *p); 629 630 void __iomem *devm_ioremap_resource(struct device *dev, struct resource *res); 631 void __iomem *devm_request_and_ioremap(struct device *dev, 632 struct resource *res); 633 634 /* allows to add/remove a custom action to devres stack */ 635 int devm_add_action(struct device *dev, void (*action)(void *), void *data); 636 void devm_remove_action(struct device *dev, void (*action)(void *), void *data); 637 638 struct device_dma_parameters { 639 /* 640 * a low level driver may set these to teach IOMMU code about 641 * sg limitations. 642 */ 643 unsigned int max_segment_size; 644 unsigned long segment_boundary_mask; 645 }; 646 647 struct acpi_device; 648 649 struct acpi_dev_node { 650 #ifdef CONFIG_ACPI 651 struct acpi_device *companion; 652 #endif 653 }; 654 655 /** 656 * struct device - The basic device structure 657 * @parent: The device's "parent" device, the device to which it is attached. 658 * In most cases, a parent device is some sort of bus or host 659 * controller. If parent is NULL, the device, is a top-level device, 660 * which is not usually what you want. 661 * @p: Holds the private data of the driver core portions of the device. 662 * See the comment of the struct device_private for detail. 663 * @kobj: A top-level, abstract class from which other classes are derived. 664 * @init_name: Initial name of the device. 665 * @type: The type of device. 666 * This identifies the device type and carries type-specific 667 * information. 668 * @mutex: Mutex to synchronize calls to its driver. 669 * @bus: Type of bus device is on. 670 * @driver: Which driver has allocated this 671 * @platform_data: Platform data specific to the device. 672 * Example: For devices on custom boards, as typical of embedded 673 * and SOC based hardware, Linux often uses platform_data to point 674 * to board-specific structures describing devices and how they 675 * are wired. That can include what ports are available, chip 676 * variants, which GPIO pins act in what additional roles, and so 677 * on. This shrinks the "Board Support Packages" (BSPs) and 678 * minimizes board-specific #ifdefs in drivers. 679 * @power: For device power management. 680 * See Documentation/power/devices.txt for details. 681 * @pm_domain: Provide callbacks that are executed during system suspend, 682 * hibernation, system resume and during runtime PM transitions 683 * along with subsystem-level and driver-level callbacks. 684 * @pins: For device pin management. 685 * See Documentation/pinctrl.txt for details. 686 * @numa_node: NUMA node this device is close to. 687 * @dma_mask: Dma mask (if dma'ble device). 688 * @coherent_dma_mask: Like dma_mask, but for alloc_coherent mapping as not all 689 * hardware supports 64-bit addresses for consistent allocations 690 * such descriptors. 691 * @dma_parms: A low level driver may set these to teach IOMMU code about 692 * segment limitations. 693 * @dma_pools: Dma pools (if dma'ble device). 694 * @dma_mem: Internal for coherent mem override. 695 * @cma_area: Contiguous memory area for dma allocations 696 * @archdata: For arch-specific additions. 697 * @of_node: Associated device tree node. 698 * @acpi_node: Associated ACPI device node. 699 * @devt: For creating the sysfs "dev". 700 * @id: device instance 701 * @devres_lock: Spinlock to protect the resource of the device. 702 * @devres_head: The resources list of the device. 703 * @knode_class: The node used to add the device to the class list. 704 * @class: The class of the device. 705 * @groups: Optional attribute groups. 706 * @release: Callback to free the device after all references have 707 * gone away. This should be set by the allocator of the 708 * device (i.e. the bus driver that discovered the device). 709 * @iommu_group: IOMMU group the device belongs to. 710 * 711 * @offline_disabled: If set, the device is permanently online. 712 * @offline: Set after successful invocation of bus type's .offline(). 713 * 714 * At the lowest level, every device in a Linux system is represented by an 715 * instance of struct device. The device structure contains the information 716 * that the device model core needs to model the system. Most subsystems, 717 * however, track additional information about the devices they host. As a 718 * result, it is rare for devices to be represented by bare device structures; 719 * instead, that structure, like kobject structures, is usually embedded within 720 * a higher-level representation of the device. 721 */ 722 struct device { 723 struct device *parent; 724 725 struct device_private *p; 726 727 struct kobject kobj; 728 const char *init_name; /* initial name of the device */ 729 const struct device_type *type; 730 731 struct mutex mutex; /* mutex to synchronize calls to 732 * its driver. 733 */ 734 735 struct bus_type *bus; /* type of bus device is on */ 736 struct device_driver *driver; /* which driver has allocated this 737 device */ 738 void *platform_data; /* Platform specific data, device 739 core doesn't touch it */ 740 struct dev_pm_info power; 741 struct dev_pm_domain *pm_domain; 742 743 #ifdef CONFIG_PINCTRL 744 struct dev_pin_info *pins; 745 #endif 746 747 #ifdef CONFIG_NUMA 748 int numa_node; /* NUMA node this device is close to */ 749 #endif 750 u64 *dma_mask; /* dma mask (if dma'able device) */ 751 u64 coherent_dma_mask;/* Like dma_mask, but for 752 alloc_coherent mappings as 753 not all hardware supports 754 64 bit addresses for consistent 755 allocations such descriptors. */ 756 757 struct device_dma_parameters *dma_parms; 758 759 struct list_head dma_pools; /* dma pools (if dma'ble) */ 760 761 struct dma_coherent_mem *dma_mem; /* internal for coherent mem 762 override */ 763 #ifdef CONFIG_DMA_CMA 764 struct cma *cma_area; /* contiguous memory area for dma 765 allocations */ 766 #endif 767 /* arch specific additions */ 768 struct dev_archdata archdata; 769 770 struct device_node *of_node; /* associated device tree node */ 771 struct acpi_dev_node acpi_node; /* associated ACPI device node */ 772 773 dev_t devt; /* dev_t, creates the sysfs "dev" */ 774 u32 id; /* device instance */ 775 776 spinlock_t devres_lock; 777 struct list_head devres_head; 778 779 struct klist_node knode_class; 780 struct class *class; 781 const struct attribute_group **groups; /* optional groups */ 782 783 void (*release)(struct device *dev); 784 struct iommu_group *iommu_group; 785 786 bool offline_disabled:1; 787 bool offline:1; 788 }; 789 790 static inline struct device *kobj_to_dev(struct kobject *kobj) 791 { 792 return container_of(kobj, struct device, kobj); 793 } 794 795 /* Get the wakeup routines, which depend on struct device */ 796 #include <linux/pm_wakeup.h> 797 798 static inline const char *dev_name(const struct device *dev) 799 { 800 /* Use the init name until the kobject becomes available */ 801 if (dev->init_name) 802 return dev->init_name; 803 804 return kobject_name(&dev->kobj); 805 } 806 807 extern __printf(2, 3) 808 int dev_set_name(struct device *dev, const char *name, ...); 809 810 #ifdef CONFIG_NUMA 811 static inline int dev_to_node(struct device *dev) 812 { 813 return dev->numa_node; 814 } 815 static inline void set_dev_node(struct device *dev, int node) 816 { 817 dev->numa_node = node; 818 } 819 #else 820 static inline int dev_to_node(struct device *dev) 821 { 822 return -1; 823 } 824 static inline void set_dev_node(struct device *dev, int node) 825 { 826 } 827 #endif 828 829 static inline struct pm_subsys_data *dev_to_psd(struct device *dev) 830 { 831 return dev ? dev->power.subsys_data : NULL; 832 } 833 834 static inline unsigned int dev_get_uevent_suppress(const struct device *dev) 835 { 836 return dev->kobj.uevent_suppress; 837 } 838 839 static inline void dev_set_uevent_suppress(struct device *dev, int val) 840 { 841 dev->kobj.uevent_suppress = val; 842 } 843 844 static inline int device_is_registered(struct device *dev) 845 { 846 return dev->kobj.state_in_sysfs; 847 } 848 849 static inline void device_enable_async_suspend(struct device *dev) 850 { 851 if (!dev->power.is_prepared) 852 dev->power.async_suspend = true; 853 } 854 855 static inline void device_disable_async_suspend(struct device *dev) 856 { 857 if (!dev->power.is_prepared) 858 dev->power.async_suspend = false; 859 } 860 861 static inline bool device_async_suspend_enabled(struct device *dev) 862 { 863 return !!dev->power.async_suspend; 864 } 865 866 static inline void pm_suspend_ignore_children(struct device *dev, bool enable) 867 { 868 dev->power.ignore_children = enable; 869 } 870 871 static inline void dev_pm_syscore_device(struct device *dev, bool val) 872 { 873 #ifdef CONFIG_PM_SLEEP 874 dev->power.syscore = val; 875 #endif 876 } 877 878 static inline void device_lock(struct device *dev) 879 { 880 mutex_lock(&dev->mutex); 881 } 882 883 static inline int device_trylock(struct device *dev) 884 { 885 return mutex_trylock(&dev->mutex); 886 } 887 888 static inline void device_unlock(struct device *dev) 889 { 890 mutex_unlock(&dev->mutex); 891 } 892 893 void driver_init(void); 894 895 /* 896 * High level routines for use by the bus drivers 897 */ 898 extern int __must_check device_register(struct device *dev); 899 extern void device_unregister(struct device *dev); 900 extern void device_initialize(struct device *dev); 901 extern int __must_check device_add(struct device *dev); 902 extern void device_del(struct device *dev); 903 extern int device_for_each_child(struct device *dev, void *data, 904 int (*fn)(struct device *dev, void *data)); 905 extern struct device *device_find_child(struct device *dev, void *data, 906 int (*match)(struct device *dev, void *data)); 907 extern int device_rename(struct device *dev, const char *new_name); 908 extern int device_move(struct device *dev, struct device *new_parent, 909 enum dpm_order dpm_order); 910 extern const char *device_get_devnode(struct device *dev, 911 umode_t *mode, kuid_t *uid, kgid_t *gid, 912 const char **tmp); 913 extern void *dev_get_drvdata(const struct device *dev); 914 extern int dev_set_drvdata(struct device *dev, void *data); 915 916 static inline bool device_supports_offline(struct device *dev) 917 { 918 return dev->bus && dev->bus->offline && dev->bus->online; 919 } 920 921 extern void lock_device_hotplug(void); 922 extern void unlock_device_hotplug(void); 923 extern int lock_device_hotplug_sysfs(void); 924 extern int device_offline(struct device *dev); 925 extern int device_online(struct device *dev); 926 /* 927 * Root device objects for grouping under /sys/devices 928 */ 929 extern struct device *__root_device_register(const char *name, 930 struct module *owner); 931 932 /* 933 * This is a macro to avoid include problems with THIS_MODULE, 934 * just as per what is done for device_schedule_callback() above. 935 */ 936 #define root_device_register(name) \ 937 __root_device_register(name, THIS_MODULE) 938 939 extern void root_device_unregister(struct device *root); 940 941 static inline void *dev_get_platdata(const struct device *dev) 942 { 943 return dev->platform_data; 944 } 945 946 /* 947 * Manual binding of a device to driver. See drivers/base/bus.c 948 * for information on use. 949 */ 950 extern int __must_check device_bind_driver(struct device *dev); 951 extern void device_release_driver(struct device *dev); 952 extern int __must_check device_attach(struct device *dev); 953 extern int __must_check driver_attach(struct device_driver *drv); 954 extern int __must_check device_reprobe(struct device *dev); 955 956 /* 957 * Easy functions for dynamically creating devices on the fly 958 */ 959 extern struct device *device_create_vargs(struct class *cls, 960 struct device *parent, 961 dev_t devt, 962 void *drvdata, 963 const char *fmt, 964 va_list vargs); 965 extern __printf(5, 6) 966 struct device *device_create(struct class *cls, struct device *parent, 967 dev_t devt, void *drvdata, 968 const char *fmt, ...); 969 extern __printf(6, 7) 970 struct device *device_create_with_groups(struct class *cls, 971 struct device *parent, dev_t devt, void *drvdata, 972 const struct attribute_group **groups, 973 const char *fmt, ...); 974 extern void device_destroy(struct class *cls, dev_t devt); 975 976 /* 977 * Platform "fixup" functions - allow the platform to have their say 978 * about devices and actions that the general device layer doesn't 979 * know about. 980 */ 981 /* Notify platform of device discovery */ 982 extern int (*platform_notify)(struct device *dev); 983 984 extern int (*platform_notify_remove)(struct device *dev); 985 986 987 /* 988 * get_device - atomically increment the reference count for the device. 989 * 990 */ 991 extern struct device *get_device(struct device *dev); 992 extern void put_device(struct device *dev); 993 994 #ifdef CONFIG_DEVTMPFS 995 extern int devtmpfs_create_node(struct device *dev); 996 extern int devtmpfs_delete_node(struct device *dev); 997 extern int devtmpfs_mount(const char *mntdir); 998 #else 999 static inline int devtmpfs_create_node(struct device *dev) { return 0; } 1000 static inline int devtmpfs_delete_node(struct device *dev) { return 0; } 1001 static inline int devtmpfs_mount(const char *mountpoint) { return 0; } 1002 #endif 1003 1004 /* drivers/base/power/shutdown.c */ 1005 extern void device_shutdown(void); 1006 1007 /* debugging and troubleshooting/diagnostic helpers. */ 1008 extern const char *dev_driver_string(const struct device *dev); 1009 1010 1011 #ifdef CONFIG_PRINTK 1012 1013 extern __printf(3, 0) 1014 int dev_vprintk_emit(int level, const struct device *dev, 1015 const char *fmt, va_list args); 1016 extern __printf(3, 4) 1017 int dev_printk_emit(int level, const struct device *dev, const char *fmt, ...); 1018 1019 extern __printf(3, 4) 1020 int dev_printk(const char *level, const struct device *dev, 1021 const char *fmt, ...); 1022 extern __printf(2, 3) 1023 int dev_emerg(const struct device *dev, const char *fmt, ...); 1024 extern __printf(2, 3) 1025 int dev_alert(const struct device *dev, const char *fmt, ...); 1026 extern __printf(2, 3) 1027 int dev_crit(const struct device *dev, const char *fmt, ...); 1028 extern __printf(2, 3) 1029 int dev_err(const struct device *dev, const char *fmt, ...); 1030 extern __printf(2, 3) 1031 int dev_warn(const struct device *dev, const char *fmt, ...); 1032 extern __printf(2, 3) 1033 int dev_notice(const struct device *dev, const char *fmt, ...); 1034 extern __printf(2, 3) 1035 int _dev_info(const struct device *dev, const char *fmt, ...); 1036 1037 #else 1038 1039 static inline __printf(3, 0) 1040 int dev_vprintk_emit(int level, const struct device *dev, 1041 const char *fmt, va_list args) 1042 { return 0; } 1043 static inline __printf(3, 4) 1044 int dev_printk_emit(int level, const struct device *dev, const char *fmt, ...) 1045 { return 0; } 1046 1047 static inline int __dev_printk(const char *level, const struct device *dev, 1048 struct va_format *vaf) 1049 { return 0; } 1050 static inline __printf(3, 4) 1051 int dev_printk(const char *level, const struct device *dev, 1052 const char *fmt, ...) 1053 { return 0; } 1054 1055 static inline __printf(2, 3) 1056 int dev_emerg(const struct device *dev, const char *fmt, ...) 1057 { return 0; } 1058 static inline __printf(2, 3) 1059 int dev_crit(const struct device *dev, const char *fmt, ...) 1060 { return 0; } 1061 static inline __printf(2, 3) 1062 int dev_alert(const struct device *dev, const char *fmt, ...) 1063 { return 0; } 1064 static inline __printf(2, 3) 1065 int dev_err(const struct device *dev, const char *fmt, ...) 1066 { return 0; } 1067 static inline __printf(2, 3) 1068 int dev_warn(const struct device *dev, const char *fmt, ...) 1069 { return 0; } 1070 static inline __printf(2, 3) 1071 int dev_notice(const struct device *dev, const char *fmt, ...) 1072 { return 0; } 1073 static inline __printf(2, 3) 1074 int _dev_info(const struct device *dev, const char *fmt, ...) 1075 { return 0; } 1076 1077 #endif 1078 1079 /* 1080 * Stupid hackaround for existing uses of non-printk uses dev_info 1081 * 1082 * Note that the definition of dev_info below is actually _dev_info 1083 * and a macro is used to avoid redefining dev_info 1084 */ 1085 1086 #define dev_info(dev, fmt, arg...) _dev_info(dev, fmt, ##arg) 1087 1088 #if defined(CONFIG_DYNAMIC_DEBUG) 1089 #define dev_dbg(dev, format, ...) \ 1090 do { \ 1091 dynamic_dev_dbg(dev, format, ##__VA_ARGS__); \ 1092 } while (0) 1093 #elif defined(DEBUG) 1094 #define dev_dbg(dev, format, arg...) \ 1095 dev_printk(KERN_DEBUG, dev, format, ##arg) 1096 #else 1097 #define dev_dbg(dev, format, arg...) \ 1098 ({ \ 1099 if (0) \ 1100 dev_printk(KERN_DEBUG, dev, format, ##arg); \ 1101 0; \ 1102 }) 1103 #endif 1104 1105 #define dev_level_ratelimited(dev_level, dev, fmt, ...) \ 1106 do { \ 1107 static DEFINE_RATELIMIT_STATE(_rs, \ 1108 DEFAULT_RATELIMIT_INTERVAL, \ 1109 DEFAULT_RATELIMIT_BURST); \ 1110 if (__ratelimit(&_rs)) \ 1111 dev_level(dev, fmt, ##__VA_ARGS__); \ 1112 } while (0) 1113 1114 #define dev_emerg_ratelimited(dev, fmt, ...) \ 1115 dev_level_ratelimited(dev_emerg, dev, fmt, ##__VA_ARGS__) 1116 #define dev_alert_ratelimited(dev, fmt, ...) \ 1117 dev_level_ratelimited(dev_alert, dev, fmt, ##__VA_ARGS__) 1118 #define dev_crit_ratelimited(dev, fmt, ...) \ 1119 dev_level_ratelimited(dev_crit, dev, fmt, ##__VA_ARGS__) 1120 #define dev_err_ratelimited(dev, fmt, ...) \ 1121 dev_level_ratelimited(dev_err, dev, fmt, ##__VA_ARGS__) 1122 #define dev_warn_ratelimited(dev, fmt, ...) \ 1123 dev_level_ratelimited(dev_warn, dev, fmt, ##__VA_ARGS__) 1124 #define dev_notice_ratelimited(dev, fmt, ...) \ 1125 dev_level_ratelimited(dev_notice, dev, fmt, ##__VA_ARGS__) 1126 #define dev_info_ratelimited(dev, fmt, ...) \ 1127 dev_level_ratelimited(dev_info, dev, fmt, ##__VA_ARGS__) 1128 #if defined(CONFIG_DYNAMIC_DEBUG) 1129 /* descriptor check is first to prevent flooding with "callbacks suppressed" */ 1130 #define dev_dbg_ratelimited(dev, fmt, ...) \ 1131 do { \ 1132 static DEFINE_RATELIMIT_STATE(_rs, \ 1133 DEFAULT_RATELIMIT_INTERVAL, \ 1134 DEFAULT_RATELIMIT_BURST); \ 1135 DEFINE_DYNAMIC_DEBUG_METADATA(descriptor, fmt); \ 1136 if (unlikely(descriptor.flags & _DPRINTK_FLAGS_PRINT) && \ 1137 __ratelimit(&_rs)) \ 1138 __dynamic_dev_dbg(&descriptor, dev, fmt, \ 1139 ##__VA_ARGS__); \ 1140 } while (0) 1141 #elif defined(DEBUG) 1142 #define dev_dbg_ratelimited(dev, fmt, ...) \ 1143 do { \ 1144 static DEFINE_RATELIMIT_STATE(_rs, \ 1145 DEFAULT_RATELIMIT_INTERVAL, \ 1146 DEFAULT_RATELIMIT_BURST); \ 1147 if (__ratelimit(&_rs)) \ 1148 dev_printk(KERN_DEBUG, dev, fmt, ##__VA_ARGS__); \ 1149 } while (0) 1150 #else 1151 #define dev_dbg_ratelimited(dev, fmt, ...) \ 1152 no_printk(KERN_DEBUG pr_fmt(fmt), ##__VA_ARGS__) 1153 #endif 1154 1155 #ifdef VERBOSE_DEBUG 1156 #define dev_vdbg dev_dbg 1157 #else 1158 #define dev_vdbg(dev, format, arg...) \ 1159 ({ \ 1160 if (0) \ 1161 dev_printk(KERN_DEBUG, dev, format, ##arg); \ 1162 0; \ 1163 }) 1164 #endif 1165 1166 /* 1167 * dev_WARN*() acts like dev_printk(), but with the key difference of 1168 * using WARN/WARN_ONCE to include file/line information and a backtrace. 1169 */ 1170 #define dev_WARN(dev, format, arg...) \ 1171 WARN(1, "%s %s: " format, dev_driver_string(dev), dev_name(dev), ## arg); 1172 1173 #define dev_WARN_ONCE(dev, condition, format, arg...) \ 1174 WARN_ONCE(condition, "%s %s: " format, \ 1175 dev_driver_string(dev), dev_name(dev), ## arg) 1176 1177 /* Create alias, so I can be autoloaded. */ 1178 #define MODULE_ALIAS_CHARDEV(major,minor) \ 1179 MODULE_ALIAS("char-major-" __stringify(major) "-" __stringify(minor)) 1180 #define MODULE_ALIAS_CHARDEV_MAJOR(major) \ 1181 MODULE_ALIAS("char-major-" __stringify(major) "-*") 1182 1183 #ifdef CONFIG_SYSFS_DEPRECATED 1184 extern long sysfs_deprecated; 1185 #else 1186 #define sysfs_deprecated 0 1187 #endif 1188 1189 /** 1190 * module_driver() - Helper macro for drivers that don't do anything 1191 * special in module init/exit. This eliminates a lot of boilerplate. 1192 * Each module may only use this macro once, and calling it replaces 1193 * module_init() and module_exit(). 1194 * 1195 * @__driver: driver name 1196 * @__register: register function for this driver type 1197 * @__unregister: unregister function for this driver type 1198 * @...: Additional arguments to be passed to __register and __unregister. 1199 * 1200 * Use this macro to construct bus specific macros for registering 1201 * drivers, and do not use it on its own. 1202 */ 1203 #define module_driver(__driver, __register, __unregister, ...) \ 1204 static int __init __driver##_init(void) \ 1205 { \ 1206 return __register(&(__driver) , ##__VA_ARGS__); \ 1207 } \ 1208 module_init(__driver##_init); \ 1209 static void __exit __driver##_exit(void) \ 1210 { \ 1211 __unregister(&(__driver) , ##__VA_ARGS__); \ 1212 } \ 1213 module_exit(__driver##_exit); 1214 1215 #endif /* _DEVICE_H_ */ 1216