1 // SPDX-License-Identifier: GPL-2.0 2 /* 3 * device.h - generic, centralized driver model 4 * 5 * Copyright (c) 2001-2003 Patrick Mochel <[email protected]> 6 * Copyright (c) 2004-2009 Greg Kroah-Hartman <[email protected]> 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/device/bus.h> 30 #include <linux/device/class.h> 31 #include <linux/device/devres.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 /* allows to add/remove a custom action to devres stack */ 285 int devm_remove_action_nowarn(struct device *dev, void (*action)(void *), void *data); 286 287 /** 288 * devm_remove_action() - removes previously added custom action 289 * @dev: Device that owns the action 290 * @action: Function implementing the action 291 * @data: Pointer to data passed to @action implementation 292 * 293 * Removes instance of @action previously added by devm_add_action(). 294 * Both action and data should match one of the existing entries. 295 */ 296 static inline 297 void devm_remove_action(struct device *dev, void (*action)(void *), void *data) 298 { 299 WARN_ON(devm_remove_action_nowarn(dev, action, data)); 300 } 301 302 void devm_release_action(struct device *dev, void (*action)(void *), void *data); 303 304 int __devm_add_action(struct device *dev, void (*action)(void *), void *data, const char *name); 305 #define devm_add_action(dev, action, data) \ 306 __devm_add_action(dev, action, data, #action) 307 308 static inline int __devm_add_action_or_reset(struct device *dev, void (*action)(void *), 309 void *data, const char *name) 310 { 311 int ret; 312 313 ret = __devm_add_action(dev, action, data, name); 314 if (ret) 315 action(data); 316 317 return ret; 318 } 319 #define devm_add_action_or_reset(dev, action, data) \ 320 __devm_add_action_or_reset(dev, action, data, #action) 321 322 /** 323 * devm_alloc_percpu - Resource-managed alloc_percpu 324 * @dev: Device to allocate per-cpu memory for 325 * @type: Type to allocate per-cpu memory for 326 * 327 * Managed alloc_percpu. Per-cpu memory allocated with this function is 328 * automatically freed on driver detach. 329 * 330 * RETURNS: 331 * Pointer to allocated memory on success, NULL on failure. 332 */ 333 #define devm_alloc_percpu(dev, type) \ 334 ((typeof(type) __percpu *)__devm_alloc_percpu((dev), sizeof(type), \ 335 __alignof__(type))) 336 337 void __percpu *__devm_alloc_percpu(struct device *dev, size_t size, 338 size_t align); 339 void devm_free_percpu(struct device *dev, void __percpu *pdata); 340 341 struct device_dma_parameters { 342 /* 343 * a low level driver may set these to teach IOMMU code about 344 * sg limitations. 345 */ 346 unsigned int max_segment_size; 347 unsigned int min_align_mask; 348 unsigned long segment_boundary_mask; 349 }; 350 351 /** 352 * enum device_link_state - Device link states. 353 * @DL_STATE_NONE: The presence of the drivers is not being tracked. 354 * @DL_STATE_DORMANT: None of the supplier/consumer drivers is present. 355 * @DL_STATE_AVAILABLE: The supplier driver is present, but the consumer is not. 356 * @DL_STATE_CONSUMER_PROBE: The consumer is probing (supplier driver present). 357 * @DL_STATE_ACTIVE: Both the supplier and consumer drivers are present. 358 * @DL_STATE_SUPPLIER_UNBIND: The supplier driver is unbinding. 359 */ 360 enum device_link_state { 361 DL_STATE_NONE = -1, 362 DL_STATE_DORMANT = 0, 363 DL_STATE_AVAILABLE, 364 DL_STATE_CONSUMER_PROBE, 365 DL_STATE_ACTIVE, 366 DL_STATE_SUPPLIER_UNBIND, 367 }; 368 369 /* 370 * Device link flags. 371 * 372 * STATELESS: The core will not remove this link automatically. 373 * AUTOREMOVE_CONSUMER: Remove the link automatically on consumer driver unbind. 374 * PM_RUNTIME: If set, the runtime PM framework will use this link. 375 * RPM_ACTIVE: Run pm_runtime_get_sync() on the supplier during link creation. 376 * AUTOREMOVE_SUPPLIER: Remove the link automatically on supplier driver unbind. 377 * AUTOPROBE_CONSUMER: Probe consumer driver automatically after supplier binds. 378 * MANAGED: The core tracks presence of supplier/consumer drivers (internal). 379 * SYNC_STATE_ONLY: Link only affects sync_state() behavior. 380 * INFERRED: Inferred from data (eg: firmware) and not from driver actions. 381 */ 382 #define DL_FLAG_STATELESS BIT(0) 383 #define DL_FLAG_AUTOREMOVE_CONSUMER BIT(1) 384 #define DL_FLAG_PM_RUNTIME BIT(2) 385 #define DL_FLAG_RPM_ACTIVE BIT(3) 386 #define DL_FLAG_AUTOREMOVE_SUPPLIER BIT(4) 387 #define DL_FLAG_AUTOPROBE_CONSUMER BIT(5) 388 #define DL_FLAG_MANAGED BIT(6) 389 #define DL_FLAG_SYNC_STATE_ONLY BIT(7) 390 #define DL_FLAG_INFERRED BIT(8) 391 #define DL_FLAG_CYCLE BIT(9) 392 393 /** 394 * enum dl_dev_state - Device driver presence tracking information. 395 * @DL_DEV_NO_DRIVER: There is no driver attached to the device. 396 * @DL_DEV_PROBING: A driver is probing. 397 * @DL_DEV_DRIVER_BOUND: The driver has been bound to the device. 398 * @DL_DEV_UNBINDING: The driver is unbinding from the device. 399 */ 400 enum dl_dev_state { 401 DL_DEV_NO_DRIVER = 0, 402 DL_DEV_PROBING, 403 DL_DEV_DRIVER_BOUND, 404 DL_DEV_UNBINDING, 405 }; 406 407 /** 408 * enum device_removable - Whether the device is removable. The criteria for a 409 * device to be classified as removable is determined by its subsystem or bus. 410 * @DEVICE_REMOVABLE_NOT_SUPPORTED: This attribute is not supported for this 411 * device (default). 412 * @DEVICE_REMOVABLE_UNKNOWN: Device location is Unknown. 413 * @DEVICE_FIXED: Device is not removable by the user. 414 * @DEVICE_REMOVABLE: Device is removable by the user. 415 */ 416 enum device_removable { 417 DEVICE_REMOVABLE_NOT_SUPPORTED = 0, /* must be 0 */ 418 DEVICE_REMOVABLE_UNKNOWN, 419 DEVICE_FIXED, 420 DEVICE_REMOVABLE, 421 }; 422 423 /** 424 * struct dev_links_info - Device data related to device links. 425 * @suppliers: List of links to supplier devices. 426 * @consumers: List of links to consumer devices. 427 * @defer_sync: Hook to global list of devices that have deferred sync_state. 428 * @status: Driver status information. 429 */ 430 struct dev_links_info { 431 struct list_head suppliers; 432 struct list_head consumers; 433 struct list_head defer_sync; 434 enum dl_dev_state status; 435 }; 436 437 /** 438 * struct dev_msi_info - Device data related to MSI 439 * @domain: The MSI interrupt domain associated to the device 440 * @data: Pointer to MSI device data 441 */ 442 struct dev_msi_info { 443 #ifdef CONFIG_GENERIC_MSI_IRQ 444 struct irq_domain *domain; 445 struct msi_device_data *data; 446 #endif 447 }; 448 449 /** 450 * enum device_physical_location_panel - Describes which panel surface of the 451 * system's housing the device connection point resides on. 452 * @DEVICE_PANEL_TOP: Device connection point is on the top panel. 453 * @DEVICE_PANEL_BOTTOM: Device connection point is on the bottom panel. 454 * @DEVICE_PANEL_LEFT: Device connection point is on the left panel. 455 * @DEVICE_PANEL_RIGHT: Device connection point is on the right panel. 456 * @DEVICE_PANEL_FRONT: Device connection point is on the front panel. 457 * @DEVICE_PANEL_BACK: Device connection point is on the back panel. 458 * @DEVICE_PANEL_UNKNOWN: The panel with device connection point is unknown. 459 */ 460 enum device_physical_location_panel { 461 DEVICE_PANEL_TOP, 462 DEVICE_PANEL_BOTTOM, 463 DEVICE_PANEL_LEFT, 464 DEVICE_PANEL_RIGHT, 465 DEVICE_PANEL_FRONT, 466 DEVICE_PANEL_BACK, 467 DEVICE_PANEL_UNKNOWN, 468 }; 469 470 /** 471 * enum device_physical_location_vertical_position - Describes vertical 472 * position of the device connection point on the panel surface. 473 * @DEVICE_VERT_POS_UPPER: Device connection point is at upper part of panel. 474 * @DEVICE_VERT_POS_CENTER: Device connection point is at center part of panel. 475 * @DEVICE_VERT_POS_LOWER: Device connection point is at lower part of panel. 476 */ 477 enum device_physical_location_vertical_position { 478 DEVICE_VERT_POS_UPPER, 479 DEVICE_VERT_POS_CENTER, 480 DEVICE_VERT_POS_LOWER, 481 }; 482 483 /** 484 * enum device_physical_location_horizontal_position - Describes horizontal 485 * position of the device connection point on the panel surface. 486 * @DEVICE_HORI_POS_LEFT: Device connection point is at left part of panel. 487 * @DEVICE_HORI_POS_CENTER: Device connection point is at center part of panel. 488 * @DEVICE_HORI_POS_RIGHT: Device connection point is at right part of panel. 489 */ 490 enum device_physical_location_horizontal_position { 491 DEVICE_HORI_POS_LEFT, 492 DEVICE_HORI_POS_CENTER, 493 DEVICE_HORI_POS_RIGHT, 494 }; 495 496 /** 497 * struct device_physical_location - Device data related to physical location 498 * of the device connection point. 499 * @panel: Panel surface of the system's housing that the device connection 500 * point resides on. 501 * @vertical_position: Vertical position of the device connection point within 502 * the panel. 503 * @horizontal_position: Horizontal position of the device connection point 504 * within the panel. 505 * @dock: Set if the device connection point resides in a docking station or 506 * port replicator. 507 * @lid: Set if this device connection point resides on the lid of laptop 508 * system. 509 */ 510 struct device_physical_location { 511 enum device_physical_location_panel panel; 512 enum device_physical_location_vertical_position vertical_position; 513 enum device_physical_location_horizontal_position horizontal_position; 514 bool dock; 515 bool lid; 516 }; 517 518 /** 519 * struct device - The basic device structure 520 * @parent: The device's "parent" device, the device to which it is attached. 521 * In most cases, a parent device is some sort of bus or host 522 * controller. If parent is NULL, the device, is a top-level device, 523 * which is not usually what you want. 524 * @p: Holds the private data of the driver core portions of the device. 525 * See the comment of the struct device_private for detail. 526 * @kobj: A top-level, abstract class from which other classes are derived. 527 * @init_name: Initial name of the device. 528 * @type: The type of device. 529 * This identifies the device type and carries type-specific 530 * information. 531 * @mutex: Mutex to synchronize calls to its driver. 532 * @bus: Type of bus device is on. 533 * @driver: Which driver has allocated this 534 * @platform_data: Platform data specific to the device. 535 * Example: For devices on custom boards, as typical of embedded 536 * and SOC based hardware, Linux often uses platform_data to point 537 * to board-specific structures describing devices and how they 538 * are wired. That can include what ports are available, chip 539 * variants, which GPIO pins act in what additional roles, and so 540 * on. This shrinks the "Board Support Packages" (BSPs) and 541 * minimizes board-specific #ifdefs in drivers. 542 * @driver_data: Private pointer for driver specific info. 543 * @links: Links to suppliers and consumers of this device. 544 * @power: For device power management. 545 * See Documentation/driver-api/pm/devices.rst for details. 546 * @pm_domain: Provide callbacks that are executed during system suspend, 547 * hibernation, system resume and during runtime PM transitions 548 * along with subsystem-level and driver-level callbacks. 549 * @em_pd: device's energy model performance domain 550 * @pins: For device pin management. 551 * See Documentation/driver-api/pin-control.rst for details. 552 * @msi: MSI related data 553 * @numa_node: NUMA node this device is close to. 554 * @dma_ops: DMA mapping operations for this device. 555 * @dma_mask: Dma mask (if dma'ble device). 556 * @coherent_dma_mask: Like dma_mask, but for alloc_coherent mapping as not all 557 * hardware supports 64-bit addresses for consistent allocations 558 * such descriptors. 559 * @bus_dma_limit: Limit of an upstream bridge or bus which imposes a smaller 560 * DMA limit than the device itself supports. 561 * @dma_range_map: map for DMA memory ranges relative to that of RAM 562 * @dma_parms: A low level driver may set these to teach IOMMU code about 563 * segment limitations. 564 * @dma_pools: Dma pools (if dma'ble device). 565 * @dma_mem: Internal for coherent mem override. 566 * @cma_area: Contiguous memory area for dma allocations 567 * @dma_io_tlb_mem: Software IO TLB allocator. Not for driver use. 568 * @dma_io_tlb_pools: List of transient swiotlb memory pools. 569 * @dma_io_tlb_lock: Protects changes to the list of active pools. 570 * @dma_uses_io_tlb: %true if device has used the software IO TLB. 571 * @archdata: For arch-specific additions. 572 * @of_node: Associated device tree node. 573 * @fwnode: Associated device node supplied by platform firmware. 574 * @devt: For creating the sysfs "dev". 575 * @id: device instance 576 * @devres_lock: Spinlock to protect the resource of the device. 577 * @devres_head: The resources list of the device. 578 * @class: The class of the device. 579 * @groups: Optional attribute groups. 580 * @release: Callback to free the device after all references have 581 * gone away. This should be set by the allocator of the 582 * device (i.e. the bus driver that discovered the device). 583 * @iommu_group: IOMMU group the device belongs to. 584 * @iommu: Per device generic IOMMU runtime data 585 * @physical_location: Describes physical location of the device connection 586 * point in the system housing. 587 * @removable: Whether the device can be removed from the system. This 588 * should be set by the subsystem / bus driver that discovered 589 * the device. 590 * 591 * @offline_disabled: If set, the device is permanently online. 592 * @offline: Set after successful invocation of bus type's .offline(). 593 * @of_node_reused: Set if the device-tree node is shared with an ancestor 594 * device. 595 * @state_synced: The hardware state of this device has been synced to match 596 * the software state of this device by calling the driver/bus 597 * sync_state() callback. 598 * @can_match: The device has matched with a driver at least once or it is in 599 * a bus (like AMBA) which can't check for matching drivers until 600 * other devices probe successfully. 601 * @dma_coherent: this particular device is dma coherent, even if the 602 * architecture supports non-coherent devices. 603 * @dma_ops_bypass: If set to %true then the dma_ops are bypassed for the 604 * streaming DMA operations (->map_* / ->unmap_* / ->sync_*), 605 * and optionall (if the coherent mask is large enough) also 606 * for dma allocations. This flag is managed by the dma ops 607 * instance from ->dma_supported. 608 * @dma_skip_sync: DMA sync operations can be skipped for coherent buffers. 609 * @dma_iommu: Device is using default IOMMU implementation for DMA and 610 * doesn't rely on dma_ops structure. 611 * 612 * At the lowest level, every device in a Linux system is represented by an 613 * instance of struct device. The device structure contains the information 614 * that the device model core needs to model the system. Most subsystems, 615 * however, track additional information about the devices they host. As a 616 * result, it is rare for devices to be represented by bare device structures; 617 * instead, that structure, like kobject structures, is usually embedded within 618 * a higher-level representation of the device. 619 */ 620 struct device { 621 struct kobject kobj; 622 struct device *parent; 623 624 struct device_private *p; 625 626 const char *init_name; /* initial name of the device */ 627 const struct device_type *type; 628 629 const struct bus_type *bus; /* type of bus device is on */ 630 struct device_driver *driver; /* which driver has allocated this 631 device */ 632 void *platform_data; /* Platform specific data, device 633 core doesn't touch it */ 634 void *driver_data; /* Driver data, set and get with 635 dev_set_drvdata/dev_get_drvdata */ 636 struct mutex mutex; /* mutex to synchronize calls to 637 * its driver. 638 */ 639 640 struct dev_links_info links; 641 struct dev_pm_info power; 642 struct dev_pm_domain *pm_domain; 643 644 #ifdef CONFIG_ENERGY_MODEL 645 struct em_perf_domain *em_pd; 646 #endif 647 648 #ifdef CONFIG_PINCTRL 649 struct dev_pin_info *pins; 650 #endif 651 struct dev_msi_info msi; 652 #ifdef CONFIG_ARCH_HAS_DMA_OPS 653 const struct dma_map_ops *dma_ops; 654 #endif 655 u64 *dma_mask; /* dma mask (if dma'able device) */ 656 u64 coherent_dma_mask;/* Like dma_mask, but for 657 alloc_coherent mappings as 658 not all hardware supports 659 64 bit addresses for consistent 660 allocations such descriptors. */ 661 u64 bus_dma_limit; /* upstream dma constraint */ 662 const struct bus_dma_region *dma_range_map; 663 664 struct device_dma_parameters *dma_parms; 665 666 struct list_head dma_pools; /* dma pools (if dma'ble) */ 667 668 #ifdef CONFIG_DMA_DECLARE_COHERENT 669 struct dma_coherent_mem *dma_mem; /* internal for coherent mem 670 override */ 671 #endif 672 #ifdef CONFIG_DMA_CMA 673 struct cma *cma_area; /* contiguous memory area for dma 674 allocations */ 675 #endif 676 #ifdef CONFIG_SWIOTLB 677 struct io_tlb_mem *dma_io_tlb_mem; 678 #endif 679 #ifdef CONFIG_SWIOTLB_DYNAMIC 680 struct list_head dma_io_tlb_pools; 681 spinlock_t dma_io_tlb_lock; 682 bool dma_uses_io_tlb; 683 #endif 684 /* arch specific additions */ 685 struct dev_archdata archdata; 686 687 struct device_node *of_node; /* associated device tree node */ 688 struct fwnode_handle *fwnode; /* firmware device node */ 689 690 #ifdef CONFIG_NUMA 691 int numa_node; /* NUMA node this device is close to */ 692 #endif 693 dev_t devt; /* dev_t, creates the sysfs "dev" */ 694 u32 id; /* device instance */ 695 696 spinlock_t devres_lock; 697 struct list_head devres_head; 698 699 const struct class *class; 700 const struct attribute_group **groups; /* optional groups */ 701 702 void (*release)(struct device *dev); 703 struct iommu_group *iommu_group; 704 struct dev_iommu *iommu; 705 706 struct device_physical_location *physical_location; 707 708 enum device_removable removable; 709 710 bool offline_disabled:1; 711 bool offline:1; 712 bool of_node_reused:1; 713 bool state_synced:1; 714 bool can_match:1; 715 #if defined(CONFIG_ARCH_HAS_SYNC_DMA_FOR_DEVICE) || \ 716 defined(CONFIG_ARCH_HAS_SYNC_DMA_FOR_CPU) || \ 717 defined(CONFIG_ARCH_HAS_SYNC_DMA_FOR_CPU_ALL) 718 bool dma_coherent:1; 719 #endif 720 #ifdef CONFIG_DMA_OPS_BYPASS 721 bool dma_ops_bypass : 1; 722 #endif 723 #ifdef CONFIG_DMA_NEED_SYNC 724 bool dma_skip_sync:1; 725 #endif 726 #ifdef CONFIG_IOMMU_DMA 727 bool dma_iommu:1; 728 #endif 729 }; 730 731 /** 732 * struct device_link - Device link representation. 733 * @supplier: The device on the supplier end of the link. 734 * @s_node: Hook to the supplier device's list of links to consumers. 735 * @consumer: The device on the consumer end of the link. 736 * @c_node: Hook to the consumer device's list of links to suppliers. 737 * @link_dev: device used to expose link details in sysfs 738 * @status: The state of the link (with respect to the presence of drivers). 739 * @flags: Link flags. 740 * @rpm_active: Whether or not the consumer device is runtime-PM-active. 741 * @kref: Count repeated addition of the same link. 742 * @rm_work: Work structure used for removing the link. 743 * @supplier_preactivated: Supplier has been made active before consumer probe. 744 */ 745 struct device_link { 746 struct device *supplier; 747 struct list_head s_node; 748 struct device *consumer; 749 struct list_head c_node; 750 struct device link_dev; 751 enum device_link_state status; 752 u32 flags; 753 refcount_t rpm_active; 754 struct kref kref; 755 struct work_struct rm_work; 756 bool supplier_preactivated; /* Owned by consumer probe. */ 757 }; 758 759 #define kobj_to_dev(__kobj) container_of_const(__kobj, struct device, kobj) 760 761 /** 762 * device_iommu_mapped - Returns true when the device DMA is translated 763 * by an IOMMU 764 * @dev: Device to perform the check on 765 */ 766 static inline bool device_iommu_mapped(struct device *dev) 767 { 768 return (dev->iommu_group != NULL); 769 } 770 771 /* Get the wakeup routines, which depend on struct device */ 772 #include <linux/pm_wakeup.h> 773 774 /** 775 * dev_name - Return a device's name. 776 * @dev: Device with name to get. 777 * Return: The kobject name of the device, or its initial name if unavailable. 778 */ 779 static inline const char *dev_name(const struct device *dev) 780 { 781 /* Use the init name until the kobject becomes available */ 782 if (dev->init_name) 783 return dev->init_name; 784 785 return kobject_name(&dev->kobj); 786 } 787 788 /** 789 * dev_bus_name - Return a device's bus/class name, if at all possible 790 * @dev: struct device to get the bus/class name of 791 * 792 * Will return the name of the bus/class the device is attached to. If it is 793 * not attached to a bus/class, an empty string will be returned. 794 */ 795 static inline const char *dev_bus_name(const struct device *dev) 796 { 797 return dev->bus ? dev->bus->name : (dev->class ? dev->class->name : ""); 798 } 799 800 __printf(2, 3) int dev_set_name(struct device *dev, const char *name, ...); 801 802 #ifdef CONFIG_NUMA 803 static inline int dev_to_node(struct device *dev) 804 { 805 return dev->numa_node; 806 } 807 static inline void set_dev_node(struct device *dev, int node) 808 { 809 dev->numa_node = node; 810 } 811 #else 812 static inline int dev_to_node(struct device *dev) 813 { 814 return NUMA_NO_NODE; 815 } 816 static inline void set_dev_node(struct device *dev, int node) 817 { 818 } 819 #endif 820 821 static inline struct irq_domain *dev_get_msi_domain(const struct device *dev) 822 { 823 #ifdef CONFIG_GENERIC_MSI_IRQ 824 return dev->msi.domain; 825 #else 826 return NULL; 827 #endif 828 } 829 830 static inline void dev_set_msi_domain(struct device *dev, struct irq_domain *d) 831 { 832 #ifdef CONFIG_GENERIC_MSI_IRQ 833 dev->msi.domain = d; 834 #endif 835 } 836 837 static inline void *dev_get_drvdata(const struct device *dev) 838 { 839 return dev->driver_data; 840 } 841 842 static inline void dev_set_drvdata(struct device *dev, void *data) 843 { 844 dev->driver_data = data; 845 } 846 847 static inline struct pm_subsys_data *dev_to_psd(struct device *dev) 848 { 849 return dev ? dev->power.subsys_data : NULL; 850 } 851 852 static inline unsigned int dev_get_uevent_suppress(const struct device *dev) 853 { 854 return dev->kobj.uevent_suppress; 855 } 856 857 static inline void dev_set_uevent_suppress(struct device *dev, int val) 858 { 859 dev->kobj.uevent_suppress = val; 860 } 861 862 static inline int device_is_registered(struct device *dev) 863 { 864 return dev->kobj.state_in_sysfs; 865 } 866 867 static inline void device_enable_async_suspend(struct device *dev) 868 { 869 if (!dev->power.is_prepared) 870 dev->power.async_suspend = true; 871 } 872 873 static inline void device_disable_async_suspend(struct device *dev) 874 { 875 if (!dev->power.is_prepared) 876 dev->power.async_suspend = false; 877 } 878 879 static inline bool device_async_suspend_enabled(struct device *dev) 880 { 881 return !!dev->power.async_suspend; 882 } 883 884 static inline bool device_pm_not_required(struct device *dev) 885 { 886 return dev->power.no_pm; 887 } 888 889 static inline void device_set_pm_not_required(struct device *dev) 890 { 891 dev->power.no_pm = true; 892 } 893 894 static inline void dev_pm_syscore_device(struct device *dev, bool val) 895 { 896 #ifdef CONFIG_PM_SLEEP 897 dev->power.syscore = val; 898 #endif 899 } 900 901 static inline void dev_pm_set_driver_flags(struct device *dev, u32 flags) 902 { 903 dev->power.driver_flags = flags; 904 } 905 906 static inline bool dev_pm_test_driver_flags(struct device *dev, u32 flags) 907 { 908 return !!(dev->power.driver_flags & flags); 909 } 910 911 static inline void device_lock(struct device *dev) 912 { 913 mutex_lock(&dev->mutex); 914 } 915 916 static inline int device_lock_interruptible(struct device *dev) 917 { 918 return mutex_lock_interruptible(&dev->mutex); 919 } 920 921 static inline int device_trylock(struct device *dev) 922 { 923 return mutex_trylock(&dev->mutex); 924 } 925 926 static inline void device_unlock(struct device *dev) 927 { 928 mutex_unlock(&dev->mutex); 929 } 930 931 DEFINE_GUARD(device, struct device *, device_lock(_T), device_unlock(_T)) 932 933 static inline void device_lock_assert(struct device *dev) 934 { 935 lockdep_assert_held(&dev->mutex); 936 } 937 938 static inline bool dev_has_sync_state(struct device *dev) 939 { 940 if (!dev) 941 return false; 942 if (dev->driver && dev->driver->sync_state) 943 return true; 944 if (dev->bus && dev->bus->sync_state) 945 return true; 946 return false; 947 } 948 949 static inline void dev_set_removable(struct device *dev, 950 enum device_removable removable) 951 { 952 dev->removable = removable; 953 } 954 955 static inline bool dev_is_removable(struct device *dev) 956 { 957 return dev->removable == DEVICE_REMOVABLE; 958 } 959 960 static inline bool dev_removable_is_valid(struct device *dev) 961 { 962 return dev->removable != DEVICE_REMOVABLE_NOT_SUPPORTED; 963 } 964 965 /* 966 * High level routines for use by the bus drivers 967 */ 968 int __must_check device_register(struct device *dev); 969 void device_unregister(struct device *dev); 970 void device_initialize(struct device *dev); 971 int __must_check device_add(struct device *dev); 972 void device_del(struct device *dev); 973 974 DEFINE_FREE(device_del, struct device *, if (_T) device_del(_T)) 975 976 int device_for_each_child(struct device *parent, void *data, 977 device_iter_t fn); 978 int device_for_each_child_reverse(struct device *parent, void *data, 979 device_iter_t fn); 980 int device_for_each_child_reverse_from(struct device *parent, 981 struct device *from, void *data, 982 device_iter_t fn); 983 struct device *device_find_child(struct device *parent, const void *data, 984 device_match_t match); 985 /** 986 * device_find_child_by_name - device iterator for locating a child device. 987 * @parent: parent struct device 988 * @name: name of the child device 989 * 990 * This is similar to the device_find_child() function above, but it 991 * returns a reference to a device that has the name @name. 992 * 993 * NOTE: you will need to drop the reference with put_device() after use. 994 */ 995 static inline struct device *device_find_child_by_name(struct device *parent, 996 const char *name) 997 { 998 return device_find_child(parent, name, device_match_name); 999 } 1000 1001 /** 1002 * device_find_any_child - device iterator for locating a child device, if any. 1003 * @parent: parent struct device 1004 * 1005 * This is similar to the device_find_child() function above, but it 1006 * returns a reference to a child device, if any. 1007 * 1008 * NOTE: you will need to drop the reference with put_device() after use. 1009 */ 1010 static inline struct device *device_find_any_child(struct device *parent) 1011 { 1012 return device_find_child(parent, NULL, device_match_any); 1013 } 1014 1015 int device_rename(struct device *dev, const char *new_name); 1016 int device_move(struct device *dev, struct device *new_parent, 1017 enum dpm_order dpm_order); 1018 int device_change_owner(struct device *dev, kuid_t kuid, kgid_t kgid); 1019 1020 static inline bool device_supports_offline(struct device *dev) 1021 { 1022 return dev->bus && dev->bus->offline && dev->bus->online; 1023 } 1024 1025 #define __device_lock_set_class(dev, name, key) \ 1026 do { \ 1027 struct device *__d2 __maybe_unused = dev; \ 1028 lock_set_class(&__d2->mutex.dep_map, name, key, 0, _THIS_IP_); \ 1029 } while (0) 1030 1031 /** 1032 * device_lock_set_class - Specify a temporary lock class while a device 1033 * is attached to a driver 1034 * @dev: device to modify 1035 * @key: lock class key data 1036 * 1037 * This must be called with the device_lock() already held, for example 1038 * from driver ->probe(). Take care to only override the default 1039 * lockdep_no_validate class. 1040 */ 1041 #ifdef CONFIG_LOCKDEP 1042 #define device_lock_set_class(dev, key) \ 1043 do { \ 1044 struct device *__d = dev; \ 1045 dev_WARN_ONCE(__d, !lockdep_match_class(&__d->mutex, \ 1046 &__lockdep_no_validate__), \ 1047 "overriding existing custom lock class\n"); \ 1048 __device_lock_set_class(__d, #key, key); \ 1049 } while (0) 1050 #else 1051 #define device_lock_set_class(dev, key) __device_lock_set_class(dev, #key, key) 1052 #endif 1053 1054 /** 1055 * device_lock_reset_class - Return a device to the default lockdep novalidate state 1056 * @dev: device to modify 1057 * 1058 * This must be called with the device_lock() already held, for example 1059 * from driver ->remove(). 1060 */ 1061 #define device_lock_reset_class(dev) \ 1062 do { \ 1063 struct device *__d __maybe_unused = dev; \ 1064 lock_set_novalidate_class(&__d->mutex.dep_map, "&dev->mutex", \ 1065 _THIS_IP_); \ 1066 } while (0) 1067 1068 void lock_device_hotplug(void); 1069 void unlock_device_hotplug(void); 1070 int lock_device_hotplug_sysfs(void); 1071 int device_offline(struct device *dev); 1072 int device_online(struct device *dev); 1073 1074 void set_primary_fwnode(struct device *dev, struct fwnode_handle *fwnode); 1075 void set_secondary_fwnode(struct device *dev, struct fwnode_handle *fwnode); 1076 void device_set_node(struct device *dev, struct fwnode_handle *fwnode); 1077 void device_set_of_node_from_dev(struct device *dev, const struct device *dev2); 1078 1079 static inline struct device_node *dev_of_node(struct device *dev) 1080 { 1081 if (!IS_ENABLED(CONFIG_OF) || !dev) 1082 return NULL; 1083 return dev->of_node; 1084 } 1085 1086 static inline int dev_num_vf(struct device *dev) 1087 { 1088 if (dev->bus && dev->bus->num_vf) 1089 return dev->bus->num_vf(dev); 1090 return 0; 1091 } 1092 1093 /* 1094 * Root device objects for grouping under /sys/devices 1095 */ 1096 struct device *__root_device_register(const char *name, struct module *owner); 1097 1098 /* This is a macro to avoid include problems with THIS_MODULE */ 1099 #define root_device_register(name) \ 1100 __root_device_register(name, THIS_MODULE) 1101 1102 void root_device_unregister(struct device *root); 1103 1104 static inline void *dev_get_platdata(const struct device *dev) 1105 { 1106 return dev->platform_data; 1107 } 1108 1109 /* 1110 * Manual binding of a device to driver. See drivers/base/bus.c 1111 * for information on use. 1112 */ 1113 int __must_check device_driver_attach(const struct device_driver *drv, 1114 struct device *dev); 1115 int __must_check device_bind_driver(struct device *dev); 1116 void device_release_driver(struct device *dev); 1117 int __must_check device_attach(struct device *dev); 1118 int __must_check driver_attach(const struct device_driver *drv); 1119 void device_initial_probe(struct device *dev); 1120 int __must_check device_reprobe(struct device *dev); 1121 1122 bool device_is_bound(struct device *dev); 1123 1124 /* 1125 * Easy functions for dynamically creating devices on the fly 1126 */ 1127 __printf(5, 6) struct device * 1128 device_create(const struct class *cls, struct device *parent, dev_t devt, 1129 void *drvdata, const char *fmt, ...); 1130 __printf(6, 7) struct device * 1131 device_create_with_groups(const struct class *cls, struct device *parent, dev_t devt, 1132 void *drvdata, const struct attribute_group **groups, 1133 const char *fmt, ...); 1134 void device_destroy(const struct class *cls, dev_t devt); 1135 1136 int __must_check device_add_groups(struct device *dev, 1137 const struct attribute_group **groups); 1138 void device_remove_groups(struct device *dev, 1139 const struct attribute_group **groups); 1140 1141 static inline int __must_check device_add_group(struct device *dev, 1142 const struct attribute_group *grp) 1143 { 1144 const struct attribute_group *groups[] = { grp, NULL }; 1145 1146 return device_add_groups(dev, groups); 1147 } 1148 1149 static inline void device_remove_group(struct device *dev, 1150 const struct attribute_group *grp) 1151 { 1152 const struct attribute_group *groups[] = { grp, NULL }; 1153 1154 return device_remove_groups(dev, groups); 1155 } 1156 1157 int __must_check devm_device_add_group(struct device *dev, 1158 const struct attribute_group *grp); 1159 1160 /* 1161 * get_device - atomically increment the reference count for the device. 1162 * 1163 */ 1164 struct device *get_device(struct device *dev); 1165 void put_device(struct device *dev); 1166 1167 DEFINE_FREE(put_device, struct device *, if (_T) put_device(_T)) 1168 1169 bool kill_device(struct device *dev); 1170 1171 #ifdef CONFIG_DEVTMPFS 1172 int devtmpfs_mount(void); 1173 #else 1174 static inline int devtmpfs_mount(void) { return 0; } 1175 #endif 1176 1177 /* drivers/base/power/shutdown.c */ 1178 void device_shutdown(void); 1179 1180 /* debugging and troubleshooting/diagnostic helpers. */ 1181 const char *dev_driver_string(const struct device *dev); 1182 1183 /* Device links interface. */ 1184 struct device_link *device_link_add(struct device *consumer, 1185 struct device *supplier, u32 flags); 1186 void device_link_del(struct device_link *link); 1187 void device_link_remove(void *consumer, struct device *supplier); 1188 void device_links_supplier_sync_state_pause(void); 1189 void device_links_supplier_sync_state_resume(void); 1190 void device_link_wait_removal(void); 1191 1192 /* Create alias, so I can be autoloaded. */ 1193 #define MODULE_ALIAS_CHARDEV(major,minor) \ 1194 MODULE_ALIAS("char-major-" __stringify(major) "-" __stringify(minor)) 1195 #define MODULE_ALIAS_CHARDEV_MAJOR(major) \ 1196 MODULE_ALIAS("char-major-" __stringify(major) "-*") 1197 1198 #endif /* _DEVICE_H_ */ 1199