1 // SPDX-License-Identifier: GPL-2.0 2 /* 3 * device.h - generic, centralized driver model 4 * 5 * Copyright (c) 2001-2003 Patrick Mochel <mochel@osdl.org> 6 * Copyright (c) 2004-2009 Greg Kroah-Hartman <gregkh@suse.de> 7 * Copyright (c) 2008-2009 Novell Inc. 8 * 9 * See Documentation/driver-api/driver-model/ for more information. 10 */ 11 12 #ifndef _DEVICE_H_ 13 #define _DEVICE_H_ 14 15 #include <linux/dev_printk.h> 16 #include <linux/energy_model.h> 17 #include <linux/ioport.h> 18 #include <linux/kobject.h> 19 #include <linux/klist.h> 20 #include <linux/list.h> 21 #include <linux/lockdep.h> 22 #include <linux/compiler.h> 23 #include <linux/types.h> 24 #include <linux/mutex.h> 25 #include <linux/pm.h> 26 #include <linux/atomic.h> 27 #include <linux/uidgid.h> 28 #include <linux/gfp.h> 29 #include <linux/overflow.h> 30 #include <linux/device/bus.h> 31 #include <linux/device/class.h> 32 #include <linux/device/driver.h> 33 #include <linux/cleanup.h> 34 #include <asm/device.h> 35 36 struct device; 37 struct device_private; 38 struct device_driver; 39 struct driver_private; 40 struct module; 41 struct class; 42 struct subsys_private; 43 struct device_node; 44 struct fwnode_handle; 45 struct iommu_group; 46 struct dev_pin_info; 47 struct dev_iommu; 48 struct msi_device_data; 49 50 /** 51 * struct subsys_interface - interfaces to device functions 52 * @name: name of the device function 53 * @subsys: subsystem of the devices to attach to 54 * @node: the list of functions registered at the subsystem 55 * @add_dev: device hookup to device function handler 56 * @remove_dev: device hookup to device function handler 57 * 58 * Simple interfaces attached to a subsystem. Multiple interfaces can 59 * attach to a subsystem and its devices. Unlike drivers, they do not 60 * exclusively claim or control devices. Interfaces usually represent 61 * a specific functionality of a subsystem/class of devices. 62 */ 63 struct subsys_interface { 64 const char *name; 65 const struct bus_type *subsys; 66 struct list_head node; 67 int (*add_dev)(struct device *dev, struct subsys_interface *sif); 68 void (*remove_dev)(struct device *dev, struct subsys_interface *sif); 69 }; 70 71 int subsys_interface_register(struct subsys_interface *sif); 72 void subsys_interface_unregister(struct subsys_interface *sif); 73 74 int subsys_system_register(const struct bus_type *subsys, 75 const struct attribute_group **groups); 76 int subsys_virtual_register(const struct bus_type *subsys, 77 const struct attribute_group **groups); 78 79 /* 80 * The type of device, "struct device" is embedded in. A class 81 * or bus can contain devices of different types 82 * like "partitions" and "disks", "mouse" and "event". 83 * This identifies the device type and carries type-specific 84 * information, equivalent to the kobj_type of a kobject. 85 * If "name" is specified, the uevent will contain it in 86 * the DEVTYPE variable. 87 */ 88 struct device_type { 89 const char *name; 90 const struct attribute_group **groups; 91 int (*uevent)(const struct device *dev, struct kobj_uevent_env *env); 92 char *(*devnode)(const struct device *dev, umode_t *mode, 93 kuid_t *uid, kgid_t *gid); 94 void (*release)(struct device *dev); 95 96 const struct dev_pm_ops *pm; 97 }; 98 99 /** 100 * struct device_attribute - Interface for exporting device attributes. 101 * @attr: sysfs attribute definition. 102 * @show: Show handler. 103 * @store: Store handler. 104 */ 105 struct device_attribute { 106 struct attribute attr; 107 ssize_t (*show)(struct device *dev, struct device_attribute *attr, 108 char *buf); 109 ssize_t (*store)(struct device *dev, struct device_attribute *attr, 110 const char *buf, size_t count); 111 }; 112 113 /** 114 * struct dev_ext_attribute - Exported device attribute with extra context. 115 * @attr: Exported device attribute. 116 * @var: Pointer to context. 117 */ 118 struct dev_ext_attribute { 119 struct device_attribute attr; 120 void *var; 121 }; 122 123 ssize_t device_show_ulong(struct device *dev, struct device_attribute *attr, 124 char *buf); 125 ssize_t device_store_ulong(struct device *dev, struct device_attribute *attr, 126 const char *buf, size_t count); 127 ssize_t device_show_int(struct device *dev, struct device_attribute *attr, 128 char *buf); 129 ssize_t device_store_int(struct device *dev, struct device_attribute *attr, 130 const char *buf, size_t count); 131 ssize_t device_show_bool(struct device *dev, struct device_attribute *attr, 132 char *buf); 133 ssize_t device_store_bool(struct device *dev, struct device_attribute *attr, 134 const char *buf, size_t count); 135 ssize_t device_show_string(struct device *dev, struct device_attribute *attr, 136 char *buf); 137 138 /** 139 * DEVICE_ATTR - Define a device attribute. 140 * @_name: Attribute name. 141 * @_mode: File mode. 142 * @_show: Show handler. Optional, but mandatory if attribute is readable. 143 * @_store: Store handler. Optional, but mandatory if attribute is writable. 144 * 145 * Convenience macro for defining a struct device_attribute. 146 * 147 * For example, ``DEVICE_ATTR(foo, 0644, foo_show, foo_store);`` expands to: 148 * 149 * .. code-block:: c 150 * 151 * struct device_attribute dev_attr_foo = { 152 * .attr = { .name = "foo", .mode = 0644 }, 153 * .show = foo_show, 154 * .store = foo_store, 155 * }; 156 */ 157 #define DEVICE_ATTR(_name, _mode, _show, _store) \ 158 struct device_attribute dev_attr_##_name = __ATTR(_name, _mode, _show, _store) 159 160 /** 161 * DEVICE_ATTR_PREALLOC - Define a preallocated device attribute. 162 * @_name: Attribute name. 163 * @_mode: File mode. 164 * @_show: Show handler. Optional, but mandatory if attribute is readable. 165 * @_store: Store handler. Optional, but mandatory if attribute is writable. 166 * 167 * Like DEVICE_ATTR(), but ``SYSFS_PREALLOC`` is set on @_mode. 168 */ 169 #define DEVICE_ATTR_PREALLOC(_name, _mode, _show, _store) \ 170 struct device_attribute dev_attr_##_name = \ 171 __ATTR_PREALLOC(_name, _mode, _show, _store) 172 173 /** 174 * DEVICE_ATTR_RW - Define a read-write device attribute. 175 * @_name: Attribute name. 176 * 177 * Like DEVICE_ATTR(), but @_mode is 0644, @_show is <_name>_show, 178 * and @_store is <_name>_store. 179 */ 180 #define DEVICE_ATTR_RW(_name) \ 181 struct device_attribute dev_attr_##_name = __ATTR_RW(_name) 182 183 /** 184 * DEVICE_ATTR_ADMIN_RW - Define an admin-only read-write device attribute. 185 * @_name: Attribute name. 186 * 187 * Like DEVICE_ATTR_RW(), but @_mode is 0600. 188 */ 189 #define DEVICE_ATTR_ADMIN_RW(_name) \ 190 struct device_attribute dev_attr_##_name = __ATTR_RW_MODE(_name, 0600) 191 192 /** 193 * DEVICE_ATTR_RO - Define a readable device attribute. 194 * @_name: Attribute name. 195 * 196 * Like DEVICE_ATTR(), but @_mode is 0444 and @_show is <_name>_show. 197 */ 198 #define DEVICE_ATTR_RO(_name) \ 199 struct device_attribute dev_attr_##_name = __ATTR_RO(_name) 200 201 /** 202 * DEVICE_ATTR_ADMIN_RO - Define an admin-only readable device attribute. 203 * @_name: Attribute name. 204 * 205 * Like DEVICE_ATTR_RO(), but @_mode is 0400. 206 */ 207 #define DEVICE_ATTR_ADMIN_RO(_name) \ 208 struct device_attribute dev_attr_##_name = __ATTR_RO_MODE(_name, 0400) 209 210 /** 211 * DEVICE_ATTR_WO - Define an admin-only writable device attribute. 212 * @_name: Attribute name. 213 * 214 * Like DEVICE_ATTR(), but @_mode is 0200 and @_store is <_name>_store. 215 */ 216 #define DEVICE_ATTR_WO(_name) \ 217 struct device_attribute dev_attr_##_name = __ATTR_WO(_name) 218 219 /** 220 * DEVICE_ULONG_ATTR - Define a device attribute backed by an unsigned long. 221 * @_name: Attribute name. 222 * @_mode: File mode. 223 * @_var: Identifier of unsigned long. 224 * 225 * Like DEVICE_ATTR(), but @_show and @_store are automatically provided 226 * such that reads and writes to the attribute from userspace affect @_var. 227 */ 228 #define DEVICE_ULONG_ATTR(_name, _mode, _var) \ 229 struct dev_ext_attribute dev_attr_##_name = \ 230 { __ATTR(_name, _mode, device_show_ulong, device_store_ulong), &(_var) } 231 232 /** 233 * DEVICE_INT_ATTR - Define a device attribute backed by an int. 234 * @_name: Attribute name. 235 * @_mode: File mode. 236 * @_var: Identifier of int. 237 * 238 * Like DEVICE_ULONG_ATTR(), but @_var is an int. 239 */ 240 #define DEVICE_INT_ATTR(_name, _mode, _var) \ 241 struct dev_ext_attribute dev_attr_##_name = \ 242 { __ATTR(_name, _mode, device_show_int, device_store_int), &(_var) } 243 244 /** 245 * DEVICE_BOOL_ATTR - Define a device attribute backed by a bool. 246 * @_name: Attribute name. 247 * @_mode: File mode. 248 * @_var: Identifier of bool. 249 * 250 * Like DEVICE_ULONG_ATTR(), but @_var is a bool. 251 */ 252 #define DEVICE_BOOL_ATTR(_name, _mode, _var) \ 253 struct dev_ext_attribute dev_attr_##_name = \ 254 { __ATTR(_name, _mode, device_show_bool, device_store_bool), &(_var) } 255 256 /** 257 * DEVICE_STRING_ATTR_RO - Define a device attribute backed by a r/o string. 258 * @_name: Attribute name. 259 * @_mode: File mode. 260 * @_var: Identifier of string. 261 * 262 * Like DEVICE_ULONG_ATTR(), but @_var is a string. Because the length of the 263 * string allocation is unknown, the attribute must be read-only. 264 */ 265 #define DEVICE_STRING_ATTR_RO(_name, _mode, _var) \ 266 struct dev_ext_attribute dev_attr_##_name = \ 267 { __ATTR(_name, (_mode) & ~0222, device_show_string, NULL), (_var) } 268 269 #define DEVICE_ATTR_IGNORE_LOCKDEP(_name, _mode, _show, _store) \ 270 struct device_attribute dev_attr_##_name = \ 271 __ATTR_IGNORE_LOCKDEP(_name, _mode, _show, _store) 272 273 int device_create_file(struct device *device, 274 const struct device_attribute *entry); 275 void device_remove_file(struct device *dev, 276 const struct device_attribute *attr); 277 bool device_remove_file_self(struct device *dev, 278 const struct device_attribute *attr); 279 int __must_check device_create_bin_file(struct device *dev, 280 const struct bin_attribute *attr); 281 void device_remove_bin_file(struct device *dev, 282 const struct bin_attribute *attr); 283 284 /* device resource management */ 285 typedef void (*dr_release_t)(struct device *dev, void *res); 286 typedef int (*dr_match_t)(struct device *dev, void *res, void *match_data); 287 288 void *__devres_alloc_node(dr_release_t release, size_t size, gfp_t gfp, 289 int nid, const char *name) __malloc; 290 #define devres_alloc(release, size, gfp) \ 291 __devres_alloc_node(release, size, gfp, NUMA_NO_NODE, #release) 292 #define devres_alloc_node(release, size, gfp, nid) \ 293 __devres_alloc_node(release, size, gfp, nid, #release) 294 295 void devres_for_each_res(struct device *dev, dr_release_t release, 296 dr_match_t match, void *match_data, 297 void (*fn)(struct device *, void *, void *), 298 void *data); 299 void devres_free(void *res); 300 void devres_add(struct device *dev, void *res); 301 void *devres_find(struct device *dev, dr_release_t release, 302 dr_match_t match, void *match_data); 303 void *devres_get(struct device *dev, void *new_res, 304 dr_match_t match, void *match_data); 305 void *devres_remove(struct device *dev, dr_release_t release, 306 dr_match_t match, void *match_data); 307 int devres_destroy(struct device *dev, dr_release_t release, 308 dr_match_t match, void *match_data); 309 int devres_release(struct device *dev, dr_release_t release, 310 dr_match_t match, void *match_data); 311 312 /* devres group */ 313 void * __must_check devres_open_group(struct device *dev, void *id, gfp_t gfp); 314 void devres_close_group(struct device *dev, void *id); 315 void devres_remove_group(struct device *dev, void *id); 316 int devres_release_group(struct device *dev, void *id); 317 318 /* managed devm_k.alloc/kfree for device drivers */ 319 void *devm_kmalloc(struct device *dev, size_t size, gfp_t gfp) __alloc_size(2); 320 void *devm_krealloc(struct device *dev, void *ptr, size_t size, 321 gfp_t gfp) __must_check __realloc_size(3); 322 __printf(3, 0) char *devm_kvasprintf(struct device *dev, gfp_t gfp, 323 const char *fmt, va_list ap) __malloc; 324 __printf(3, 4) char *devm_kasprintf(struct device *dev, gfp_t gfp, 325 const char *fmt, ...) __malloc; 326 static inline void *devm_kzalloc(struct device *dev, size_t size, gfp_t gfp) 327 { 328 return devm_kmalloc(dev, size, gfp | __GFP_ZERO); 329 } 330 static inline void *devm_kmalloc_array(struct device *dev, 331 size_t n, size_t size, gfp_t flags) 332 { 333 size_t bytes; 334 335 if (unlikely(check_mul_overflow(n, size, &bytes))) 336 return NULL; 337 338 return devm_kmalloc(dev, bytes, flags); 339 } 340 static inline void *devm_kcalloc(struct device *dev, 341 size_t n, size_t size, gfp_t flags) 342 { 343 return devm_kmalloc_array(dev, n, size, flags | __GFP_ZERO); 344 } 345 static inline __realloc_size(3, 4) void * __must_check 346 devm_krealloc_array(struct device *dev, void *p, size_t new_n, size_t new_size, gfp_t flags) 347 { 348 size_t bytes; 349 350 if (unlikely(check_mul_overflow(new_n, new_size, &bytes))) 351 return NULL; 352 353 return devm_krealloc(dev, p, bytes, flags); 354 } 355 356 void devm_kfree(struct device *dev, const void *p); 357 char *devm_kstrdup(struct device *dev, const char *s, gfp_t gfp) __malloc; 358 const char *devm_kstrdup_const(struct device *dev, const char *s, gfp_t gfp); 359 void *devm_kmemdup(struct device *dev, const void *src, size_t len, gfp_t gfp) 360 __realloc_size(3); 361 362 unsigned long devm_get_free_pages(struct device *dev, 363 gfp_t gfp_mask, unsigned int order); 364 void devm_free_pages(struct device *dev, unsigned long addr); 365 366 #ifdef CONFIG_HAS_IOMEM 367 void __iomem *devm_ioremap_resource(struct device *dev, 368 const struct resource *res); 369 void __iomem *devm_ioremap_resource_wc(struct device *dev, 370 const struct resource *res); 371 372 void __iomem *devm_of_iomap(struct device *dev, 373 struct device_node *node, int index, 374 resource_size_t *size); 375 #else 376 377 static inline 378 void __iomem *devm_ioremap_resource(struct device *dev, 379 const struct resource *res) 380 { 381 return ERR_PTR(-EINVAL); 382 } 383 384 static inline 385 void __iomem *devm_ioremap_resource_wc(struct device *dev, 386 const struct resource *res) 387 { 388 return ERR_PTR(-EINVAL); 389 } 390 391 static inline 392 void __iomem *devm_of_iomap(struct device *dev, 393 struct device_node *node, int index, 394 resource_size_t *size) 395 { 396 return ERR_PTR(-EINVAL); 397 } 398 399 #endif 400 401 /* allows to add/remove a custom action to devres stack */ 402 void devm_remove_action(struct device *dev, void (*action)(void *), void *data); 403 void devm_release_action(struct device *dev, void (*action)(void *), void *data); 404 405 int __devm_add_action(struct device *dev, void (*action)(void *), void *data, const char *name); 406 #define devm_add_action(dev, action, data) \ 407 __devm_add_action(dev, action, data, #action) 408 409 static inline int __devm_add_action_or_reset(struct device *dev, void (*action)(void *), 410 void *data, const char *name) 411 { 412 int ret; 413 414 ret = __devm_add_action(dev, action, data, name); 415 if (ret) 416 action(data); 417 418 return ret; 419 } 420 #define devm_add_action_or_reset(dev, action, data) \ 421 __devm_add_action_or_reset(dev, action, data, #action) 422 423 /** 424 * devm_alloc_percpu - Resource-managed alloc_percpu 425 * @dev: Device to allocate per-cpu memory for 426 * @type: Type to allocate per-cpu memory for 427 * 428 * Managed alloc_percpu. Per-cpu memory allocated with this function is 429 * automatically freed on driver detach. 430 * 431 * RETURNS: 432 * Pointer to allocated memory on success, NULL on failure. 433 */ 434 #define devm_alloc_percpu(dev, type) \ 435 ((typeof(type) __percpu *)__devm_alloc_percpu((dev), sizeof(type), \ 436 __alignof__(type))) 437 438 void __percpu *__devm_alloc_percpu(struct device *dev, size_t size, 439 size_t align); 440 void devm_free_percpu(struct device *dev, void __percpu *pdata); 441 442 struct device_dma_parameters { 443 /* 444 * a low level driver may set these to teach IOMMU code about 445 * sg limitations. 446 */ 447 unsigned int max_segment_size; 448 unsigned int min_align_mask; 449 unsigned long segment_boundary_mask; 450 }; 451 452 /** 453 * enum device_link_state - Device link states. 454 * @DL_STATE_NONE: The presence of the drivers is not being tracked. 455 * @DL_STATE_DORMANT: None of the supplier/consumer drivers is present. 456 * @DL_STATE_AVAILABLE: The supplier driver is present, but the consumer is not. 457 * @DL_STATE_CONSUMER_PROBE: The consumer is probing (supplier driver present). 458 * @DL_STATE_ACTIVE: Both the supplier and consumer drivers are present. 459 * @DL_STATE_SUPPLIER_UNBIND: The supplier driver is unbinding. 460 */ 461 enum device_link_state { 462 DL_STATE_NONE = -1, 463 DL_STATE_DORMANT = 0, 464 DL_STATE_AVAILABLE, 465 DL_STATE_CONSUMER_PROBE, 466 DL_STATE_ACTIVE, 467 DL_STATE_SUPPLIER_UNBIND, 468 }; 469 470 /* 471 * Device link flags. 472 * 473 * STATELESS: The core will not remove this link automatically. 474 * AUTOREMOVE_CONSUMER: Remove the link automatically on consumer driver unbind. 475 * PM_RUNTIME: If set, the runtime PM framework will use this link. 476 * RPM_ACTIVE: Run pm_runtime_get_sync() on the supplier during link creation. 477 * AUTOREMOVE_SUPPLIER: Remove the link automatically on supplier driver unbind. 478 * AUTOPROBE_CONSUMER: Probe consumer driver automatically after supplier binds. 479 * MANAGED: The core tracks presence of supplier/consumer drivers (internal). 480 * SYNC_STATE_ONLY: Link only affects sync_state() behavior. 481 * INFERRED: Inferred from data (eg: firmware) and not from driver actions. 482 */ 483 #define DL_FLAG_STATELESS BIT(0) 484 #define DL_FLAG_AUTOREMOVE_CONSUMER BIT(1) 485 #define DL_FLAG_PM_RUNTIME BIT(2) 486 #define DL_FLAG_RPM_ACTIVE BIT(3) 487 #define DL_FLAG_AUTOREMOVE_SUPPLIER BIT(4) 488 #define DL_FLAG_AUTOPROBE_CONSUMER BIT(5) 489 #define DL_FLAG_MANAGED BIT(6) 490 #define DL_FLAG_SYNC_STATE_ONLY BIT(7) 491 #define DL_FLAG_INFERRED BIT(8) 492 #define DL_FLAG_CYCLE BIT(9) 493 494 /** 495 * enum dl_dev_state - Device driver presence tracking information. 496 * @DL_DEV_NO_DRIVER: There is no driver attached to the device. 497 * @DL_DEV_PROBING: A driver is probing. 498 * @DL_DEV_DRIVER_BOUND: The driver has been bound to the device. 499 * @DL_DEV_UNBINDING: The driver is unbinding from the device. 500 */ 501 enum dl_dev_state { 502 DL_DEV_NO_DRIVER = 0, 503 DL_DEV_PROBING, 504 DL_DEV_DRIVER_BOUND, 505 DL_DEV_UNBINDING, 506 }; 507 508 /** 509 * enum device_removable - Whether the device is removable. The criteria for a 510 * device to be classified as removable is determined by its subsystem or bus. 511 * @DEVICE_REMOVABLE_NOT_SUPPORTED: This attribute is not supported for this 512 * device (default). 513 * @DEVICE_REMOVABLE_UNKNOWN: Device location is Unknown. 514 * @DEVICE_FIXED: Device is not removable by the user. 515 * @DEVICE_REMOVABLE: Device is removable by the user. 516 */ 517 enum device_removable { 518 DEVICE_REMOVABLE_NOT_SUPPORTED = 0, /* must be 0 */ 519 DEVICE_REMOVABLE_UNKNOWN, 520 DEVICE_FIXED, 521 DEVICE_REMOVABLE, 522 }; 523 524 /** 525 * struct dev_links_info - Device data related to device links. 526 * @suppliers: List of links to supplier devices. 527 * @consumers: List of links to consumer devices. 528 * @defer_sync: Hook to global list of devices that have deferred sync_state. 529 * @status: Driver status information. 530 */ 531 struct dev_links_info { 532 struct list_head suppliers; 533 struct list_head consumers; 534 struct list_head defer_sync; 535 enum dl_dev_state status; 536 }; 537 538 /** 539 * struct dev_msi_info - Device data related to MSI 540 * @domain: The MSI interrupt domain associated to the device 541 * @data: Pointer to MSI device data 542 */ 543 struct dev_msi_info { 544 #ifdef CONFIG_GENERIC_MSI_IRQ 545 struct irq_domain *domain; 546 struct msi_device_data *data; 547 #endif 548 }; 549 550 /** 551 * enum device_physical_location_panel - Describes which panel surface of the 552 * system's housing the device connection point resides on. 553 * @DEVICE_PANEL_TOP: Device connection point is on the top panel. 554 * @DEVICE_PANEL_BOTTOM: Device connection point is on the bottom panel. 555 * @DEVICE_PANEL_LEFT: Device connection point is on the left panel. 556 * @DEVICE_PANEL_RIGHT: Device connection point is on the right panel. 557 * @DEVICE_PANEL_FRONT: Device connection point is on the front panel. 558 * @DEVICE_PANEL_BACK: Device connection point is on the back panel. 559 * @DEVICE_PANEL_UNKNOWN: The panel with device connection point is unknown. 560 */ 561 enum device_physical_location_panel { 562 DEVICE_PANEL_TOP, 563 DEVICE_PANEL_BOTTOM, 564 DEVICE_PANEL_LEFT, 565 DEVICE_PANEL_RIGHT, 566 DEVICE_PANEL_FRONT, 567 DEVICE_PANEL_BACK, 568 DEVICE_PANEL_UNKNOWN, 569 }; 570 571 /** 572 * enum device_physical_location_vertical_position - Describes vertical 573 * position of the device connection point on the panel surface. 574 * @DEVICE_VERT_POS_UPPER: Device connection point is at upper part of panel. 575 * @DEVICE_VERT_POS_CENTER: Device connection point is at center part of panel. 576 * @DEVICE_VERT_POS_LOWER: Device connection point is at lower part of panel. 577 */ 578 enum device_physical_location_vertical_position { 579 DEVICE_VERT_POS_UPPER, 580 DEVICE_VERT_POS_CENTER, 581 DEVICE_VERT_POS_LOWER, 582 }; 583 584 /** 585 * enum device_physical_location_horizontal_position - Describes horizontal 586 * position of the device connection point on the panel surface. 587 * @DEVICE_HORI_POS_LEFT: Device connection point is at left part of panel. 588 * @DEVICE_HORI_POS_CENTER: Device connection point is at center part of panel. 589 * @DEVICE_HORI_POS_RIGHT: Device connection point is at right part of panel. 590 */ 591 enum device_physical_location_horizontal_position { 592 DEVICE_HORI_POS_LEFT, 593 DEVICE_HORI_POS_CENTER, 594 DEVICE_HORI_POS_RIGHT, 595 }; 596 597 /** 598 * struct device_physical_location - Device data related to physical location 599 * of the device connection point. 600 * @panel: Panel surface of the system's housing that the device connection 601 * point resides on. 602 * @vertical_position: Vertical position of the device connection point within 603 * the panel. 604 * @horizontal_position: Horizontal position of the device connection point 605 * within the panel. 606 * @dock: Set if the device connection point resides in a docking station or 607 * port replicator. 608 * @lid: Set if this device connection point resides on the lid of laptop 609 * system. 610 */ 611 struct device_physical_location { 612 enum device_physical_location_panel panel; 613 enum device_physical_location_vertical_position vertical_position; 614 enum device_physical_location_horizontal_position horizontal_position; 615 bool dock; 616 bool lid; 617 }; 618 619 /** 620 * struct device - The basic device structure 621 * @parent: The device's "parent" device, the device to which it is attached. 622 * In most cases, a parent device is some sort of bus or host 623 * controller. If parent is NULL, the device, is a top-level device, 624 * which is not usually what you want. 625 * @p: Holds the private data of the driver core portions of the device. 626 * See the comment of the struct device_private for detail. 627 * @kobj: A top-level, abstract class from which other classes are derived. 628 * @init_name: Initial name of the device. 629 * @type: The type of device. 630 * This identifies the device type and carries type-specific 631 * information. 632 * @mutex: Mutex to synchronize calls to its driver. 633 * @bus: Type of bus device is on. 634 * @driver: Which driver has allocated this 635 * @platform_data: Platform data specific to the device. 636 * Example: For devices on custom boards, as typical of embedded 637 * and SOC based hardware, Linux often uses platform_data to point 638 * to board-specific structures describing devices and how they 639 * are wired. That can include what ports are available, chip 640 * variants, which GPIO pins act in what additional roles, and so 641 * on. This shrinks the "Board Support Packages" (BSPs) and 642 * minimizes board-specific #ifdefs in drivers. 643 * @driver_data: Private pointer for driver specific info. 644 * @links: Links to suppliers and consumers of this device. 645 * @power: For device power management. 646 * See Documentation/driver-api/pm/devices.rst for details. 647 * @pm_domain: Provide callbacks that are executed during system suspend, 648 * hibernation, system resume and during runtime PM transitions 649 * along with subsystem-level and driver-level callbacks. 650 * @em_pd: device's energy model performance domain 651 * @pins: For device pin management. 652 * See Documentation/driver-api/pin-control.rst for details. 653 * @msi: MSI related data 654 * @numa_node: NUMA node this device is close to. 655 * @dma_ops: DMA mapping operations for this device. 656 * @dma_mask: Dma mask (if dma'ble device). 657 * @coherent_dma_mask: Like dma_mask, but for alloc_coherent mapping as not all 658 * hardware supports 64-bit addresses for consistent allocations 659 * such descriptors. 660 * @bus_dma_limit: Limit of an upstream bridge or bus which imposes a smaller 661 * DMA limit than the device itself supports. 662 * @dma_range_map: map for DMA memory ranges relative to that of RAM 663 * @dma_parms: A low level driver may set these to teach IOMMU code about 664 * segment limitations. 665 * @dma_pools: Dma pools (if dma'ble device). 666 * @dma_mem: Internal for coherent mem override. 667 * @cma_area: Contiguous memory area for dma allocations 668 * @dma_io_tlb_mem: Software IO TLB allocator. Not for driver use. 669 * @dma_io_tlb_pools: List of transient swiotlb memory pools. 670 * @dma_io_tlb_lock: Protects changes to the list of active pools. 671 * @dma_uses_io_tlb: %true if device has used the software IO TLB. 672 * @archdata: For arch-specific additions. 673 * @of_node: Associated device tree node. 674 * @fwnode: Associated device node supplied by platform firmware. 675 * @devt: For creating the sysfs "dev". 676 * @id: device instance 677 * @devres_lock: Spinlock to protect the resource of the device. 678 * @devres_head: The resources list of the device. 679 * @class: The class of the device. 680 * @groups: Optional attribute groups. 681 * @release: Callback to free the device after all references have 682 * gone away. This should be set by the allocator of the 683 * device (i.e. the bus driver that discovered the device). 684 * @iommu_group: IOMMU group the device belongs to. 685 * @iommu: Per device generic IOMMU runtime data 686 * @physical_location: Describes physical location of the device connection 687 * point in the system housing. 688 * @removable: Whether the device can be removed from the system. This 689 * should be set by the subsystem / bus driver that discovered 690 * the device. 691 * 692 * @offline_disabled: If set, the device is permanently online. 693 * @offline: Set after successful invocation of bus type's .offline(). 694 * @of_node_reused: Set if the device-tree node is shared with an ancestor 695 * device. 696 * @state_synced: The hardware state of this device has been synced to match 697 * the software state of this device by calling the driver/bus 698 * sync_state() callback. 699 * @can_match: The device has matched with a driver at least once or it is in 700 * a bus (like AMBA) which can't check for matching drivers until 701 * other devices probe successfully. 702 * @dma_coherent: this particular device is dma coherent, even if the 703 * architecture supports non-coherent devices. 704 * @dma_ops_bypass: If set to %true then the dma_ops are bypassed for the 705 * streaming DMA operations (->map_* / ->unmap_* / ->sync_*), 706 * and optionall (if the coherent mask is large enough) also 707 * for dma allocations. This flag is managed by the dma ops 708 * instance from ->dma_supported. 709 * @dma_skip_sync: DMA sync operations can be skipped for coherent buffers. 710 * 711 * At the lowest level, every device in a Linux system is represented by an 712 * instance of struct device. The device structure contains the information 713 * that the device model core needs to model the system. Most subsystems, 714 * however, track additional information about the devices they host. As a 715 * result, it is rare for devices to be represented by bare device structures; 716 * instead, that structure, like kobject structures, is usually embedded within 717 * a higher-level representation of the device. 718 */ 719 struct device { 720 struct kobject kobj; 721 struct device *parent; 722 723 struct device_private *p; 724 725 const char *init_name; /* initial name of the device */ 726 const struct device_type *type; 727 728 const struct bus_type *bus; /* type of bus device is on */ 729 struct device_driver *driver; /* which driver has allocated this 730 device */ 731 void *platform_data; /* Platform specific data, device 732 core doesn't touch it */ 733 void *driver_data; /* Driver data, set and get with 734 dev_set_drvdata/dev_get_drvdata */ 735 struct mutex mutex; /* mutex to synchronize calls to 736 * its driver. 737 */ 738 739 struct dev_links_info links; 740 struct dev_pm_info power; 741 struct dev_pm_domain *pm_domain; 742 743 #ifdef CONFIG_ENERGY_MODEL 744 struct em_perf_domain *em_pd; 745 #endif 746 747 #ifdef CONFIG_PINCTRL 748 struct dev_pin_info *pins; 749 #endif 750 struct dev_msi_info msi; 751 #ifdef CONFIG_DMA_OPS 752 const struct dma_map_ops *dma_ops; 753 #endif 754 u64 *dma_mask; /* dma mask (if dma'able device) */ 755 u64 coherent_dma_mask;/* Like dma_mask, but for 756 alloc_coherent mappings as 757 not all hardware supports 758 64 bit addresses for consistent 759 allocations such descriptors. */ 760 u64 bus_dma_limit; /* upstream dma constraint */ 761 const struct bus_dma_region *dma_range_map; 762 763 struct device_dma_parameters *dma_parms; 764 765 struct list_head dma_pools; /* dma pools (if dma'ble) */ 766 767 #ifdef CONFIG_DMA_DECLARE_COHERENT 768 struct dma_coherent_mem *dma_mem; /* internal for coherent mem 769 override */ 770 #endif 771 #ifdef CONFIG_DMA_CMA 772 struct cma *cma_area; /* contiguous memory area for dma 773 allocations */ 774 #endif 775 #ifdef CONFIG_SWIOTLB 776 struct io_tlb_mem *dma_io_tlb_mem; 777 #endif 778 #ifdef CONFIG_SWIOTLB_DYNAMIC 779 struct list_head dma_io_tlb_pools; 780 spinlock_t dma_io_tlb_lock; 781 bool dma_uses_io_tlb; 782 #endif 783 /* arch specific additions */ 784 struct dev_archdata archdata; 785 786 struct device_node *of_node; /* associated device tree node */ 787 struct fwnode_handle *fwnode; /* firmware device node */ 788 789 #ifdef CONFIG_NUMA 790 int numa_node; /* NUMA node this device is close to */ 791 #endif 792 dev_t devt; /* dev_t, creates the sysfs "dev" */ 793 u32 id; /* device instance */ 794 795 spinlock_t devres_lock; 796 struct list_head devres_head; 797 798 const struct class *class; 799 const struct attribute_group **groups; /* optional groups */ 800 801 void (*release)(struct device *dev); 802 struct iommu_group *iommu_group; 803 struct dev_iommu *iommu; 804 805 struct device_physical_location *physical_location; 806 807 enum device_removable removable; 808 809 bool offline_disabled:1; 810 bool offline:1; 811 bool of_node_reused:1; 812 bool state_synced:1; 813 bool can_match:1; 814 #if defined(CONFIG_ARCH_HAS_SYNC_DMA_FOR_DEVICE) || \ 815 defined(CONFIG_ARCH_HAS_SYNC_DMA_FOR_CPU) || \ 816 defined(CONFIG_ARCH_HAS_SYNC_DMA_FOR_CPU_ALL) 817 bool dma_coherent:1; 818 #endif 819 #ifdef CONFIG_DMA_OPS_BYPASS 820 bool dma_ops_bypass : 1; 821 #endif 822 #ifdef CONFIG_DMA_NEED_SYNC 823 bool dma_skip_sync:1; 824 #endif 825 }; 826 827 /** 828 * struct device_link - Device link representation. 829 * @supplier: The device on the supplier end of the link. 830 * @s_node: Hook to the supplier device's list of links to consumers. 831 * @consumer: The device on the consumer end of the link. 832 * @c_node: Hook to the consumer device's list of links to suppliers. 833 * @link_dev: device used to expose link details in sysfs 834 * @status: The state of the link (with respect to the presence of drivers). 835 * @flags: Link flags. 836 * @rpm_active: Whether or not the consumer device is runtime-PM-active. 837 * @kref: Count repeated addition of the same link. 838 * @rm_work: Work structure used for removing the link. 839 * @supplier_preactivated: Supplier has been made active before consumer probe. 840 */ 841 struct device_link { 842 struct device *supplier; 843 struct list_head s_node; 844 struct device *consumer; 845 struct list_head c_node; 846 struct device link_dev; 847 enum device_link_state status; 848 u32 flags; 849 refcount_t rpm_active; 850 struct kref kref; 851 struct work_struct rm_work; 852 bool supplier_preactivated; /* Owned by consumer probe. */ 853 }; 854 855 #define kobj_to_dev(__kobj) container_of_const(__kobj, struct device, kobj) 856 857 /** 858 * device_iommu_mapped - Returns true when the device DMA is translated 859 * by an IOMMU 860 * @dev: Device to perform the check on 861 */ 862 static inline bool device_iommu_mapped(struct device *dev) 863 { 864 return (dev->iommu_group != NULL); 865 } 866 867 /* Get the wakeup routines, which depend on struct device */ 868 #include <linux/pm_wakeup.h> 869 870 /** 871 * dev_name - Return a device's name. 872 * @dev: Device with name to get. 873 * Return: The kobject name of the device, or its initial name if unavailable. 874 */ 875 static inline const char *dev_name(const struct device *dev) 876 { 877 /* Use the init name until the kobject becomes available */ 878 if (dev->init_name) 879 return dev->init_name; 880 881 return kobject_name(&dev->kobj); 882 } 883 884 /** 885 * dev_bus_name - Return a device's bus/class name, if at all possible 886 * @dev: struct device to get the bus/class name of 887 * 888 * Will return the name of the bus/class the device is attached to. If it is 889 * not attached to a bus/class, an empty string will be returned. 890 */ 891 static inline const char *dev_bus_name(const struct device *dev) 892 { 893 return dev->bus ? dev->bus->name : (dev->class ? dev->class->name : ""); 894 } 895 896 __printf(2, 3) int dev_set_name(struct device *dev, const char *name, ...); 897 898 #ifdef CONFIG_NUMA 899 static inline int dev_to_node(struct device *dev) 900 { 901 return dev->numa_node; 902 } 903 static inline void set_dev_node(struct device *dev, int node) 904 { 905 dev->numa_node = node; 906 } 907 #else 908 static inline int dev_to_node(struct device *dev) 909 { 910 return NUMA_NO_NODE; 911 } 912 static inline void set_dev_node(struct device *dev, int node) 913 { 914 } 915 #endif 916 917 static inline struct irq_domain *dev_get_msi_domain(const struct device *dev) 918 { 919 #ifdef CONFIG_GENERIC_MSI_IRQ 920 return dev->msi.domain; 921 #else 922 return NULL; 923 #endif 924 } 925 926 static inline void dev_set_msi_domain(struct device *dev, struct irq_domain *d) 927 { 928 #ifdef CONFIG_GENERIC_MSI_IRQ 929 dev->msi.domain = d; 930 #endif 931 } 932 933 static inline void *dev_get_drvdata(const struct device *dev) 934 { 935 return dev->driver_data; 936 } 937 938 static inline void dev_set_drvdata(struct device *dev, void *data) 939 { 940 dev->driver_data = data; 941 } 942 943 static inline struct pm_subsys_data *dev_to_psd(struct device *dev) 944 { 945 return dev ? dev->power.subsys_data : NULL; 946 } 947 948 static inline unsigned int dev_get_uevent_suppress(const struct device *dev) 949 { 950 return dev->kobj.uevent_suppress; 951 } 952 953 static inline void dev_set_uevent_suppress(struct device *dev, int val) 954 { 955 dev->kobj.uevent_suppress = val; 956 } 957 958 static inline int device_is_registered(struct device *dev) 959 { 960 return dev->kobj.state_in_sysfs; 961 } 962 963 static inline void device_enable_async_suspend(struct device *dev) 964 { 965 if (!dev->power.is_prepared) 966 dev->power.async_suspend = true; 967 } 968 969 static inline void device_disable_async_suspend(struct device *dev) 970 { 971 if (!dev->power.is_prepared) 972 dev->power.async_suspend = false; 973 } 974 975 static inline bool device_async_suspend_enabled(struct device *dev) 976 { 977 return !!dev->power.async_suspend; 978 } 979 980 static inline bool device_pm_not_required(struct device *dev) 981 { 982 return dev->power.no_pm; 983 } 984 985 static inline void device_set_pm_not_required(struct device *dev) 986 { 987 dev->power.no_pm = true; 988 } 989 990 static inline void dev_pm_syscore_device(struct device *dev, bool val) 991 { 992 #ifdef CONFIG_PM_SLEEP 993 dev->power.syscore = val; 994 #endif 995 } 996 997 static inline void dev_pm_set_driver_flags(struct device *dev, u32 flags) 998 { 999 dev->power.driver_flags = flags; 1000 } 1001 1002 static inline bool dev_pm_test_driver_flags(struct device *dev, u32 flags) 1003 { 1004 return !!(dev->power.driver_flags & flags); 1005 } 1006 1007 static inline void device_lock(struct device *dev) 1008 { 1009 mutex_lock(&dev->mutex); 1010 } 1011 1012 static inline int device_lock_interruptible(struct device *dev) 1013 { 1014 return mutex_lock_interruptible(&dev->mutex); 1015 } 1016 1017 static inline int device_trylock(struct device *dev) 1018 { 1019 return mutex_trylock(&dev->mutex); 1020 } 1021 1022 static inline void device_unlock(struct device *dev) 1023 { 1024 mutex_unlock(&dev->mutex); 1025 } 1026 1027 DEFINE_GUARD(device, struct device *, device_lock(_T), device_unlock(_T)) 1028 1029 static inline void device_lock_assert(struct device *dev) 1030 { 1031 lockdep_assert_held(&dev->mutex); 1032 } 1033 1034 static inline struct device_node *dev_of_node(struct device *dev) 1035 { 1036 if (!IS_ENABLED(CONFIG_OF) || !dev) 1037 return NULL; 1038 return dev->of_node; 1039 } 1040 1041 static inline bool dev_has_sync_state(struct device *dev) 1042 { 1043 if (!dev) 1044 return false; 1045 if (dev->driver && dev->driver->sync_state) 1046 return true; 1047 if (dev->bus && dev->bus->sync_state) 1048 return true; 1049 return false; 1050 } 1051 1052 static inline void dev_set_removable(struct device *dev, 1053 enum device_removable removable) 1054 { 1055 dev->removable = removable; 1056 } 1057 1058 static inline bool dev_is_removable(struct device *dev) 1059 { 1060 return dev->removable == DEVICE_REMOVABLE; 1061 } 1062 1063 static inline bool dev_removable_is_valid(struct device *dev) 1064 { 1065 return dev->removable != DEVICE_REMOVABLE_NOT_SUPPORTED; 1066 } 1067 1068 /* 1069 * High level routines for use by the bus drivers 1070 */ 1071 int __must_check device_register(struct device *dev); 1072 void device_unregister(struct device *dev); 1073 void device_initialize(struct device *dev); 1074 int __must_check device_add(struct device *dev); 1075 void device_del(struct device *dev); 1076 1077 DEFINE_FREE(device_del, struct device *, if (_T) device_del(_T)) 1078 1079 int device_for_each_child(struct device *dev, void *data, 1080 int (*fn)(struct device *dev, void *data)); 1081 int device_for_each_child_reverse(struct device *dev, void *data, 1082 int (*fn)(struct device *dev, void *data)); 1083 struct device *device_find_child(struct device *dev, void *data, 1084 int (*match)(struct device *dev, void *data)); 1085 struct device *device_find_child_by_name(struct device *parent, 1086 const char *name); 1087 struct device *device_find_any_child(struct device *parent); 1088 1089 int device_rename(struct device *dev, const char *new_name); 1090 int device_move(struct device *dev, struct device *new_parent, 1091 enum dpm_order dpm_order); 1092 int device_change_owner(struct device *dev, kuid_t kuid, kgid_t kgid); 1093 1094 static inline bool device_supports_offline(struct device *dev) 1095 { 1096 return dev->bus && dev->bus->offline && dev->bus->online; 1097 } 1098 1099 #define __device_lock_set_class(dev, name, key) \ 1100 do { \ 1101 struct device *__d2 __maybe_unused = dev; \ 1102 lock_set_class(&__d2->mutex.dep_map, name, key, 0, _THIS_IP_); \ 1103 } while (0) 1104 1105 /** 1106 * device_lock_set_class - Specify a temporary lock class while a device 1107 * is attached to a driver 1108 * @dev: device to modify 1109 * @key: lock class key data 1110 * 1111 * This must be called with the device_lock() already held, for example 1112 * from driver ->probe(). Take care to only override the default 1113 * lockdep_no_validate class. 1114 */ 1115 #ifdef CONFIG_LOCKDEP 1116 #define device_lock_set_class(dev, key) \ 1117 do { \ 1118 struct device *__d = dev; \ 1119 dev_WARN_ONCE(__d, !lockdep_match_class(&__d->mutex, \ 1120 &__lockdep_no_validate__), \ 1121 "overriding existing custom lock class\n"); \ 1122 __device_lock_set_class(__d, #key, key); \ 1123 } while (0) 1124 #else 1125 #define device_lock_set_class(dev, key) __device_lock_set_class(dev, #key, key) 1126 #endif 1127 1128 /** 1129 * device_lock_reset_class - Return a device to the default lockdep novalidate state 1130 * @dev: device to modify 1131 * 1132 * This must be called with the device_lock() already held, for example 1133 * from driver ->remove(). 1134 */ 1135 #define device_lock_reset_class(dev) \ 1136 do { \ 1137 struct device *__d __maybe_unused = dev; \ 1138 lock_set_novalidate_class(&__d->mutex.dep_map, "&dev->mutex", \ 1139 _THIS_IP_); \ 1140 } while (0) 1141 1142 void lock_device_hotplug(void); 1143 void unlock_device_hotplug(void); 1144 int lock_device_hotplug_sysfs(void); 1145 int device_offline(struct device *dev); 1146 int device_online(struct device *dev); 1147 void set_primary_fwnode(struct device *dev, struct fwnode_handle *fwnode); 1148 void set_secondary_fwnode(struct device *dev, struct fwnode_handle *fwnode); 1149 void device_set_of_node_from_dev(struct device *dev, const struct device *dev2); 1150 void device_set_node(struct device *dev, struct fwnode_handle *fwnode); 1151 1152 static inline int dev_num_vf(struct device *dev) 1153 { 1154 if (dev->bus && dev->bus->num_vf) 1155 return dev->bus->num_vf(dev); 1156 return 0; 1157 } 1158 1159 /* 1160 * Root device objects for grouping under /sys/devices 1161 */ 1162 struct device *__root_device_register(const char *name, struct module *owner); 1163 1164 /* This is a macro to avoid include problems with THIS_MODULE */ 1165 #define root_device_register(name) \ 1166 __root_device_register(name, THIS_MODULE) 1167 1168 void root_device_unregister(struct device *root); 1169 1170 static inline void *dev_get_platdata(const struct device *dev) 1171 { 1172 return dev->platform_data; 1173 } 1174 1175 /* 1176 * Manual binding of a device to driver. See drivers/base/bus.c 1177 * for information on use. 1178 */ 1179 int __must_check device_driver_attach(struct device_driver *drv, 1180 struct device *dev); 1181 int __must_check device_bind_driver(struct device *dev); 1182 void device_release_driver(struct device *dev); 1183 int __must_check device_attach(struct device *dev); 1184 int __must_check driver_attach(struct device_driver *drv); 1185 void device_initial_probe(struct device *dev); 1186 int __must_check device_reprobe(struct device *dev); 1187 1188 bool device_is_bound(struct device *dev); 1189 1190 /* 1191 * Easy functions for dynamically creating devices on the fly 1192 */ 1193 __printf(5, 6) struct device * 1194 device_create(const struct class *cls, struct device *parent, dev_t devt, 1195 void *drvdata, const char *fmt, ...); 1196 __printf(6, 7) struct device * 1197 device_create_with_groups(const struct class *cls, struct device *parent, dev_t devt, 1198 void *drvdata, const struct attribute_group **groups, 1199 const char *fmt, ...); 1200 void device_destroy(const struct class *cls, dev_t devt); 1201 1202 int __must_check device_add_groups(struct device *dev, 1203 const struct attribute_group **groups); 1204 void device_remove_groups(struct device *dev, 1205 const struct attribute_group **groups); 1206 1207 static inline int __must_check device_add_group(struct device *dev, 1208 const struct attribute_group *grp) 1209 { 1210 const struct attribute_group *groups[] = { grp, NULL }; 1211 1212 return device_add_groups(dev, groups); 1213 } 1214 1215 static inline void device_remove_group(struct device *dev, 1216 const struct attribute_group *grp) 1217 { 1218 const struct attribute_group *groups[] = { grp, NULL }; 1219 1220 return device_remove_groups(dev, groups); 1221 } 1222 1223 int __must_check devm_device_add_group(struct device *dev, 1224 const struct attribute_group *grp); 1225 1226 /* 1227 * get_device - atomically increment the reference count for the device. 1228 * 1229 */ 1230 struct device *get_device(struct device *dev); 1231 void put_device(struct device *dev); 1232 1233 DEFINE_FREE(put_device, struct device *, if (_T) put_device(_T)) 1234 1235 bool kill_device(struct device *dev); 1236 1237 #ifdef CONFIG_DEVTMPFS 1238 int devtmpfs_mount(void); 1239 #else 1240 static inline int devtmpfs_mount(void) { return 0; } 1241 #endif 1242 1243 /* drivers/base/power/shutdown.c */ 1244 void device_shutdown(void); 1245 1246 /* debugging and troubleshooting/diagnostic helpers. */ 1247 const char *dev_driver_string(const struct device *dev); 1248 1249 /* Device links interface. */ 1250 struct device_link *device_link_add(struct device *consumer, 1251 struct device *supplier, u32 flags); 1252 void device_link_del(struct device_link *link); 1253 void device_link_remove(void *consumer, struct device *supplier); 1254 void device_links_supplier_sync_state_pause(void); 1255 void device_links_supplier_sync_state_resume(void); 1256 void device_link_wait_removal(void); 1257 1258 /* Create alias, so I can be autoloaded. */ 1259 #define MODULE_ALIAS_CHARDEV(major,minor) \ 1260 MODULE_ALIAS("char-major-" __stringify(major) "-" __stringify(minor)) 1261 #define MODULE_ALIAS_CHARDEV_MAJOR(major) \ 1262 MODULE_ALIAS("char-major-" __stringify(major) "-*") 1263 1264 #endif /* _DEVICE_H_ */ 1265