linux/include/linux/device.h
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   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/ioport.h>
  17#include <linux/kobject.h>
  18#include <linux/klist.h>
  19#include <linux/list.h>
  20#include <linux/lockdep.h>
  21#include <linux/compiler.h>
  22#include <linux/types.h>
  23#include <linux/mutex.h>
  24#include <linux/pm.h>
  25#include <linux/atomic.h>
  26#include <linux/uidgid.h>
  27#include <linux/gfp.h>
  28#include <linux/overflow.h>
  29#include <linux/device/bus.h>
  30#include <linux/device/class.h>
  31#include <linux/device/driver.h>
  32#include <asm/device.h>
  33
  34struct device;
  35struct device_private;
  36struct device_driver;
  37struct driver_private;
  38struct module;
  39struct class;
  40struct subsys_private;
  41struct device_node;
  42struct fwnode_handle;
  43struct iommu_ops;
  44struct iommu_group;
  45struct iommu_fwspec;
  46struct dev_pin_info;
  47struct iommu_param;
  48
  49/**
  50 * struct subsys_interface - interfaces to device functions
  51 * @name:       name of the device function
  52 * @subsys:     subsytem of the devices to attach to
  53 * @node:       the list of functions registered at the subsystem
  54 * @add_dev:    device hookup to device function handler
  55 * @remove_dev: device hookup to device function handler
  56 *
  57 * Simple interfaces attached to a subsystem. Multiple interfaces can
  58 * attach to a subsystem and its devices. Unlike drivers, they do not
  59 * exclusively claim or control devices. Interfaces usually represent
  60 * a specific functionality of a subsystem/class of devices.
  61 */
  62struct subsys_interface {
  63        const char *name;
  64        struct bus_type *subsys;
  65        struct list_head node;
  66        int (*add_dev)(struct device *dev, struct subsys_interface *sif);
  67        void (*remove_dev)(struct device *dev, struct subsys_interface *sif);
  68};
  69
  70int subsys_interface_register(struct subsys_interface *sif);
  71void subsys_interface_unregister(struct subsys_interface *sif);
  72
  73int subsys_system_register(struct bus_type *subsys,
  74                           const struct attribute_group **groups);
  75int subsys_virtual_register(struct bus_type *subsys,
  76                            const struct attribute_group **groups);
  77
  78/*
  79 * The type of device, "struct device" is embedded in. A class
  80 * or bus can contain devices of different types
  81 * like "partitions" and "disks", "mouse" and "event".
  82 * This identifies the device type and carries type-specific
  83 * information, equivalent to the kobj_type of a kobject.
  84 * If "name" is specified, the uevent will contain it in
  85 * the DEVTYPE variable.
  86 */
  87struct device_type {
  88        const char *name;
  89        const struct attribute_group **groups;
  90        int (*uevent)(struct device *dev, struct kobj_uevent_env *env);
  91        char *(*devnode)(struct device *dev, umode_t *mode,
  92                         kuid_t *uid, kgid_t *gid);
  93        void (*release)(struct device *dev);
  94
  95        const struct dev_pm_ops *pm;
  96};
  97
  98/* interface for exporting device attributes */
  99struct device_attribute {
 100        struct attribute        attr;
 101        ssize_t (*show)(struct device *dev, struct device_attribute *attr,
 102                        char *buf);
 103        ssize_t (*store)(struct device *dev, struct device_attribute *attr,
 104                         const char *buf, size_t count);
 105};
 106
 107struct dev_ext_attribute {
 108        struct device_attribute attr;
 109        void *var;
 110};
 111
 112ssize_t device_show_ulong(struct device *dev, struct device_attribute *attr,
 113                          char *buf);
 114ssize_t device_store_ulong(struct device *dev, struct device_attribute *attr,
 115                           const char *buf, size_t count);
 116ssize_t device_show_int(struct device *dev, struct device_attribute *attr,
 117                        char *buf);
 118ssize_t device_store_int(struct device *dev, struct device_attribute *attr,
 119                         const char *buf, size_t count);
 120ssize_t device_show_bool(struct device *dev, struct device_attribute *attr,
 121                        char *buf);
 122ssize_t device_store_bool(struct device *dev, struct device_attribute *attr,
 123                         const char *buf, size_t count);
 124
 125#define DEVICE_ATTR(_name, _mode, _show, _store) \
 126        struct device_attribute dev_attr_##_name = __ATTR(_name, _mode, _show, _store)
 127#define DEVICE_ATTR_PREALLOC(_name, _mode, _show, _store) \
 128        struct device_attribute dev_attr_##_name = \
 129                __ATTR_PREALLOC(_name, _mode, _show, _store)
 130#define DEVICE_ATTR_RW(_name) \
 131        struct device_attribute dev_attr_##_name = __ATTR_RW(_name)
 132#define DEVICE_ATTR_RO(_name) \
 133        struct device_attribute dev_attr_##_name = __ATTR_RO(_name)
 134#define DEVICE_ATTR_WO(_name) \
 135        struct device_attribute dev_attr_##_name = __ATTR_WO(_name)
 136#define DEVICE_ULONG_ATTR(_name, _mode, _var) \
 137        struct dev_ext_attribute dev_attr_##_name = \
 138                { __ATTR(_name, _mode, device_show_ulong, device_store_ulong), &(_var) }
 139#define DEVICE_INT_ATTR(_name, _mode, _var) \
 140        struct dev_ext_attribute dev_attr_##_name = \
 141                { __ATTR(_name, _mode, device_show_int, device_store_int), &(_var) }
 142#define DEVICE_BOOL_ATTR(_name, _mode, _var) \
 143        struct dev_ext_attribute dev_attr_##_name = \
 144                { __ATTR(_name, _mode, device_show_bool, device_store_bool), &(_var) }
 145#define DEVICE_ATTR_IGNORE_LOCKDEP(_name, _mode, _show, _store) \
 146        struct device_attribute dev_attr_##_name =              \
 147                __ATTR_IGNORE_LOCKDEP(_name, _mode, _show, _store)
 148
 149extern int device_create_file(struct device *device,
 150                              const struct device_attribute *entry);
 151extern void device_remove_file(struct device *dev,
 152                               const struct device_attribute *attr);
 153extern bool device_remove_file_self(struct device *dev,
 154                                    const struct device_attribute *attr);
 155extern int __must_check device_create_bin_file(struct device *dev,
 156                                        const struct bin_attribute *attr);
 157extern void device_remove_bin_file(struct device *dev,
 158                                   const struct bin_attribute *attr);
 159
 160/* device resource management */
 161typedef void (*dr_release_t)(struct device *dev, void *res);
 162typedef int (*dr_match_t)(struct device *dev, void *res, void *match_data);
 163
 164#ifdef CONFIG_DEBUG_DEVRES
 165extern void *__devres_alloc_node(dr_release_t release, size_t size, gfp_t gfp,
 166                                 int nid, const char *name) __malloc;
 167#define devres_alloc(release, size, gfp) \
 168        __devres_alloc_node(release, size, gfp, NUMA_NO_NODE, #release)
 169#define devres_alloc_node(release, size, gfp, nid) \
 170        __devres_alloc_node(release, size, gfp, nid, #release)
 171#else
 172extern void *devres_alloc_node(dr_release_t release, size_t size, gfp_t gfp,
 173                               int nid) __malloc;
 174static inline void *devres_alloc(dr_release_t release, size_t size, gfp_t gfp)
 175{
 176        return devres_alloc_node(release, size, gfp, NUMA_NO_NODE);
 177}
 178#endif
 179
 180extern void devres_for_each_res(struct device *dev, dr_release_t release,
 181                                dr_match_t match, void *match_data,
 182                                void (*fn)(struct device *, void *, void *),
 183                                void *data);
 184extern void devres_free(void *res);
 185extern void devres_add(struct device *dev, void *res);
 186extern void *devres_find(struct device *dev, dr_release_t release,
 187                         dr_match_t match, void *match_data);
 188extern void *devres_get(struct device *dev, void *new_res,
 189                        dr_match_t match, void *match_data);
 190extern void *devres_remove(struct device *dev, dr_release_t release,
 191                           dr_match_t match, void *match_data);
 192extern int devres_destroy(struct device *dev, dr_release_t release,
 193                          dr_match_t match, void *match_data);
 194extern int devres_release(struct device *dev, dr_release_t release,
 195                          dr_match_t match, void *match_data);
 196
 197/* devres group */
 198extern void * __must_check devres_open_group(struct device *dev, void *id,
 199                                             gfp_t gfp);
 200extern void devres_close_group(struct device *dev, void *id);
 201extern void devres_remove_group(struct device *dev, void *id);
 202extern int devres_release_group(struct device *dev, void *id);
 203
 204/* managed devm_k.alloc/kfree for device drivers */
 205extern void *devm_kmalloc(struct device *dev, size_t size, gfp_t gfp) __malloc;
 206extern __printf(3, 0)
 207char *devm_kvasprintf(struct device *dev, gfp_t gfp, const char *fmt,
 208                      va_list ap) __malloc;
 209extern __printf(3, 4)
 210char *devm_kasprintf(struct device *dev, gfp_t gfp, const char *fmt, ...) __malloc;
 211static inline void *devm_kzalloc(struct device *dev, size_t size, gfp_t gfp)
 212{
 213        return devm_kmalloc(dev, size, gfp | __GFP_ZERO);
 214}
 215static inline void *devm_kmalloc_array(struct device *dev,
 216                                       size_t n, size_t size, gfp_t flags)
 217{
 218        size_t bytes;
 219
 220        if (unlikely(check_mul_overflow(n, size, &bytes)))
 221                return NULL;
 222
 223        return devm_kmalloc(dev, bytes, flags);
 224}
 225static inline void *devm_kcalloc(struct device *dev,
 226                                 size_t n, size_t size, gfp_t flags)
 227{
 228        return devm_kmalloc_array(dev, n, size, flags | __GFP_ZERO);
 229}
 230extern void devm_kfree(struct device *dev, const void *p);
 231extern char *devm_kstrdup(struct device *dev, const char *s, gfp_t gfp) __malloc;
 232extern const char *devm_kstrdup_const(struct device *dev,
 233                                      const char *s, gfp_t gfp);
 234extern void *devm_kmemdup(struct device *dev, const void *src, size_t len,
 235                          gfp_t gfp);
 236
 237extern unsigned long devm_get_free_pages(struct device *dev,
 238                                         gfp_t gfp_mask, unsigned int order);
 239extern void devm_free_pages(struct device *dev, unsigned long addr);
 240
 241void __iomem *devm_ioremap_resource(struct device *dev,
 242                                    const struct resource *res);
 243void __iomem *devm_ioremap_resource_wc(struct device *dev,
 244                                       const struct resource *res);
 245
 246void __iomem *devm_of_iomap(struct device *dev,
 247                            struct device_node *node, int index,
 248                            resource_size_t *size);
 249
 250/* allows to add/remove a custom action to devres stack */
 251int devm_add_action(struct device *dev, void (*action)(void *), void *data);
 252void devm_remove_action(struct device *dev, void (*action)(void *), void *data);
 253void devm_release_action(struct device *dev, void (*action)(void *), void *data);
 254
 255static inline int devm_add_action_or_reset(struct device *dev,
 256                                           void (*action)(void *), void *data)
 257{
 258        int ret;
 259
 260        ret = devm_add_action(dev, action, data);
 261        if (ret)
 262                action(data);
 263
 264        return ret;
 265}
 266
 267/**
 268 * devm_alloc_percpu - Resource-managed alloc_percpu
 269 * @dev: Device to allocate per-cpu memory for
 270 * @type: Type to allocate per-cpu memory for
 271 *
 272 * Managed alloc_percpu. Per-cpu memory allocated with this function is
 273 * automatically freed on driver detach.
 274 *
 275 * RETURNS:
 276 * Pointer to allocated memory on success, NULL on failure.
 277 */
 278#define devm_alloc_percpu(dev, type)      \
 279        ((typeof(type) __percpu *)__devm_alloc_percpu((dev), sizeof(type), \
 280                                                      __alignof__(type)))
 281
 282void __percpu *__devm_alloc_percpu(struct device *dev, size_t size,
 283                                   size_t align);
 284void devm_free_percpu(struct device *dev, void __percpu *pdata);
 285
 286struct device_dma_parameters {
 287        /*
 288         * a low level driver may set these to teach IOMMU code about
 289         * sg limitations.
 290         */
 291        unsigned int max_segment_size;
 292        unsigned long segment_boundary_mask;
 293};
 294
 295/**
 296 * struct device_connection - Device Connection Descriptor
 297 * @fwnode: The device node of the connected device
 298 * @endpoint: The names of the two devices connected together
 299 * @id: Unique identifier for the connection
 300 * @list: List head, private, for internal use only
 301 *
 302 * NOTE: @fwnode is not used together with @endpoint. @fwnode is used when
 303 * platform firmware defines the connection. When the connection is registered
 304 * with device_connection_add() @endpoint is used instead.
 305 */
 306struct device_connection {
 307        struct fwnode_handle    *fwnode;
 308        const char              *endpoint[2];
 309        const char              *id;
 310        struct list_head        list;
 311};
 312
 313typedef void *(*devcon_match_fn_t)(struct device_connection *con, int ep,
 314                                   void *data);
 315
 316void *fwnode_connection_find_match(struct fwnode_handle *fwnode,
 317                                   const char *con_id, void *data,
 318                                   devcon_match_fn_t match);
 319void *device_connection_find_match(struct device *dev, const char *con_id,
 320                                   void *data, devcon_match_fn_t match);
 321
 322struct device *device_connection_find(struct device *dev, const char *con_id);
 323
 324void device_connection_add(struct device_connection *con);
 325void device_connection_remove(struct device_connection *con);
 326
 327/**
 328 * device_connections_add - Add multiple device connections at once
 329 * @cons: Zero terminated array of device connection descriptors
 330 */
 331static inline void device_connections_add(struct device_connection *cons)
 332{
 333        struct device_connection *c;
 334
 335        for (c = cons; c->endpoint[0]; c++)
 336                device_connection_add(c);
 337}
 338
 339/**
 340 * device_connections_remove - Remove multiple device connections at once
 341 * @cons: Zero terminated array of device connection descriptors
 342 */
 343static inline void device_connections_remove(struct device_connection *cons)
 344{
 345        struct device_connection *c;
 346
 347        for (c = cons; c->endpoint[0]; c++)
 348                device_connection_remove(c);
 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 */
 360enum 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 */
 381#define DL_FLAG_STATELESS               BIT(0)
 382#define DL_FLAG_AUTOREMOVE_CONSUMER     BIT(1)
 383#define DL_FLAG_PM_RUNTIME              BIT(2)
 384#define DL_FLAG_RPM_ACTIVE              BIT(3)
 385#define DL_FLAG_AUTOREMOVE_SUPPLIER     BIT(4)
 386#define DL_FLAG_AUTOPROBE_CONSUMER      BIT(5)
 387#define DL_FLAG_MANAGED                 BIT(6)
 388#define DL_FLAG_SYNC_STATE_ONLY         BIT(7)
 389
 390/**
 391 * struct device_link - Device link representation.
 392 * @supplier: The device on the supplier end of the link.
 393 * @s_node: Hook to the supplier device's list of links to consumers.
 394 * @consumer: The device on the consumer end of the link.
 395 * @c_node: Hook to the consumer device's list of links to suppliers.
 396 * @status: The state of the link (with respect to the presence of drivers).
 397 * @flags: Link flags.
 398 * @rpm_active: Whether or not the consumer device is runtime-PM-active.
 399 * @kref: Count repeated addition of the same link.
 400 * @rcu_head: An RCU head to use for deferred execution of SRCU callbacks.
 401 * @supplier_preactivated: Supplier has been made active before consumer probe.
 402 */
 403struct device_link {
 404        struct device *supplier;
 405        struct list_head s_node;
 406        struct device *consumer;
 407        struct list_head c_node;
 408        enum device_link_state status;
 409        u32 flags;
 410        refcount_t rpm_active;
 411        struct kref kref;
 412#ifdef CONFIG_SRCU
 413        struct rcu_head rcu_head;
 414#endif
 415        bool supplier_preactivated; /* Owned by consumer probe. */
 416};
 417
 418/**
 419 * enum dl_dev_state - Device driver presence tracking information.
 420 * @DL_DEV_NO_DRIVER: There is no driver attached to the device.
 421 * @DL_DEV_PROBING: A driver is probing.
 422 * @DL_DEV_DRIVER_BOUND: The driver has been bound to the device.
 423 * @DL_DEV_UNBINDING: The driver is unbinding from the device.
 424 */
 425enum dl_dev_state {
 426        DL_DEV_NO_DRIVER = 0,
 427        DL_DEV_PROBING,
 428        DL_DEV_DRIVER_BOUND,
 429        DL_DEV_UNBINDING,
 430};
 431
 432/**
 433 * struct dev_links_info - Device data related to device links.
 434 * @suppliers: List of links to supplier devices.
 435 * @consumers: List of links to consumer devices.
 436 * @needs_suppliers: Hook to global list of devices waiting for suppliers.
 437 * @defer_sync: Hook to global list of devices that have deferred sync_state.
 438 * @need_for_probe: If needs_suppliers is on a list, this indicates if the
 439 *                  suppliers are needed for probe or not.
 440 * @status: Driver status information.
 441 */
 442struct dev_links_info {
 443        struct list_head suppliers;
 444        struct list_head consumers;
 445        struct list_head needs_suppliers;
 446        struct list_head defer_sync;
 447        bool need_for_probe;
 448        enum dl_dev_state status;
 449};
 450
 451/**
 452 * struct device - The basic device structure
 453 * @parent:     The device's "parent" device, the device to which it is attached.
 454 *              In most cases, a parent device is some sort of bus or host
 455 *              controller. If parent is NULL, the device, is a top-level device,
 456 *              which is not usually what you want.
 457 * @p:          Holds the private data of the driver core portions of the device.
 458 *              See the comment of the struct device_private for detail.
 459 * @kobj:       A top-level, abstract class from which other classes are derived.
 460 * @init_name:  Initial name of the device.
 461 * @type:       The type of device.
 462 *              This identifies the device type and carries type-specific
 463 *              information.
 464 * @mutex:      Mutex to synchronize calls to its driver.
 465 * @lockdep_mutex: An optional debug lock that a subsystem can use as a
 466 *              peer lock to gain localized lockdep coverage of the device_lock.
 467 * @bus:        Type of bus device is on.
 468 * @driver:     Which driver has allocated this
 469 * @platform_data: Platform data specific to the device.
 470 *              Example: For devices on custom boards, as typical of embedded
 471 *              and SOC based hardware, Linux often uses platform_data to point
 472 *              to board-specific structures describing devices and how they
 473 *              are wired.  That can include what ports are available, chip
 474 *              variants, which GPIO pins act in what additional roles, and so
 475 *              on.  This shrinks the "Board Support Packages" (BSPs) and
 476 *              minimizes board-specific #ifdefs in drivers.
 477 * @driver_data: Private pointer for driver specific info.
 478 * @links:      Links to suppliers and consumers of this device.
 479 * @power:      For device power management.
 480 *              See Documentation/driver-api/pm/devices.rst for details.
 481 * @pm_domain:  Provide callbacks that are executed during system suspend,
 482 *              hibernation, system resume and during runtime PM transitions
 483 *              along with subsystem-level and driver-level callbacks.
 484 * @pins:       For device pin management.
 485 *              See Documentation/driver-api/pinctl.rst for details.
 486 * @msi_list:   Hosts MSI descriptors
 487 * @msi_domain: The generic MSI domain this device is using.
 488 * @numa_node:  NUMA node this device is close to.
 489 * @dma_ops:    DMA mapping operations for this device.
 490 * @dma_mask:   Dma mask (if dma'ble device).
 491 * @coherent_dma_mask: Like dma_mask, but for alloc_coherent mapping as not all
 492 *              hardware supports 64-bit addresses for consistent allocations
 493 *              such descriptors.
 494 * @bus_dma_limit: Limit of an upstream bridge or bus which imposes a smaller
 495 *              DMA limit than the device itself supports.
 496 * @dma_pfn_offset: offset of DMA memory range relatively of RAM
 497 * @dma_parms:  A low level driver may set these to teach IOMMU code about
 498 *              segment limitations.
 499 * @dma_pools:  Dma pools (if dma'ble device).
 500 * @dma_mem:    Internal for coherent mem override.
 501 * @cma_area:   Contiguous memory area for dma allocations
 502 * @archdata:   For arch-specific additions.
 503 * @of_node:    Associated device tree node.
 504 * @fwnode:     Associated device node supplied by platform firmware.
 505 * @devt:       For creating the sysfs "dev".
 506 * @id:         device instance
 507 * @devres_lock: Spinlock to protect the resource of the device.
 508 * @devres_head: The resources list of the device.
 509 * @knode_class: The node used to add the device to the class list.
 510 * @class:      The class of the device.
 511 * @groups:     Optional attribute groups.
 512 * @release:    Callback to free the device after all references have
 513 *              gone away. This should be set by the allocator of the
 514 *              device (i.e. the bus driver that discovered the device).
 515 * @iommu_group: IOMMU group the device belongs to.
 516 * @iommu_fwspec: IOMMU-specific properties supplied by firmware.
 517 * @iommu_param: Per device generic IOMMU runtime data
 518 *
 519 * @offline_disabled: If set, the device is permanently online.
 520 * @offline:    Set after successful invocation of bus type's .offline().
 521 * @of_node_reused: Set if the device-tree node is shared with an ancestor
 522 *              device.
 523 * @state_synced: The hardware state of this device has been synced to match
 524 *                the software state of this device by calling the driver/bus
 525 *                sync_state() callback.
 526 * @dma_coherent: this particular device is dma coherent, even if the
 527 *              architecture supports non-coherent devices.
 528 *
 529 * At the lowest level, every device in a Linux system is represented by an
 530 * instance of struct device. The device structure contains the information
 531 * that the device model core needs to model the system. Most subsystems,
 532 * however, track additional information about the devices they host. As a
 533 * result, it is rare for devices to be represented by bare device structures;
 534 * instead, that structure, like kobject structures, is usually embedded within
 535 * a higher-level representation of the device.
 536 */
 537struct device {
 538        struct kobject kobj;
 539        struct device           *parent;
 540
 541        struct device_private   *p;
 542
 543        const char              *init_name; /* initial name of the device */
 544        const struct device_type *type;
 545
 546        struct bus_type *bus;           /* type of bus device is on */
 547        struct device_driver *driver;   /* which driver has allocated this
 548                                           device */
 549        void            *platform_data; /* Platform specific data, device
 550                                           core doesn't touch it */
 551        void            *driver_data;   /* Driver data, set and get with
 552                                           dev_set_drvdata/dev_get_drvdata */
 553#ifdef CONFIG_PROVE_LOCKING
 554        struct mutex            lockdep_mutex;
 555#endif
 556        struct mutex            mutex;  /* mutex to synchronize calls to
 557                                         * its driver.
 558                                         */
 559
 560        struct dev_links_info   links;
 561        struct dev_pm_info      power;
 562        struct dev_pm_domain    *pm_domain;
 563
 564#ifdef CONFIG_GENERIC_MSI_IRQ_DOMAIN
 565        struct irq_domain       *msi_domain;
 566#endif
 567#ifdef CONFIG_PINCTRL
 568        struct dev_pin_info     *pins;
 569#endif
 570#ifdef CONFIG_GENERIC_MSI_IRQ
 571        struct list_head        msi_list;
 572#endif
 573
 574        const struct dma_map_ops *dma_ops;
 575        u64             *dma_mask;      /* dma mask (if dma'able device) */
 576        u64             coherent_dma_mask;/* Like dma_mask, but for
 577                                             alloc_coherent mappings as
 578                                             not all hardware supports
 579                                             64 bit addresses for consistent
 580                                             allocations such descriptors. */
 581        u64             bus_dma_limit;  /* upstream dma constraint */
 582        unsigned long   dma_pfn_offset;
 583
 584        struct device_dma_parameters *dma_parms;
 585
 586        struct list_head        dma_pools;      /* dma pools (if dma'ble) */
 587
 588#ifdef CONFIG_DMA_DECLARE_COHERENT
 589        struct dma_coherent_mem *dma_mem; /* internal for coherent mem
 590                                             override */
 591#endif
 592#ifdef CONFIG_DMA_CMA
 593        struct cma *cma_area;           /* contiguous memory area for dma
 594                                           allocations */
 595#endif
 596        /* arch specific additions */
 597        struct dev_archdata     archdata;
 598
 599        struct device_node      *of_node; /* associated device tree node */
 600        struct fwnode_handle    *fwnode; /* firmware device node */
 601
 602#ifdef CONFIG_NUMA
 603        int             numa_node;      /* NUMA node this device is close to */
 604#endif
 605        dev_t                   devt;   /* dev_t, creates the sysfs "dev" */
 606        u32                     id;     /* device instance */
 607
 608        spinlock_t              devres_lock;
 609        struct list_head        devres_head;
 610
 611        struct class            *class;
 612        const struct attribute_group **groups;  /* optional groups */
 613
 614        void    (*release)(struct device *dev);
 615        struct iommu_group      *iommu_group;
 616        struct iommu_fwspec     *iommu_fwspec;
 617        struct iommu_param      *iommu_param;
 618
 619        bool                    offline_disabled:1;
 620        bool                    offline:1;
 621        bool                    of_node_reused:1;
 622        bool                    state_synced:1;
 623#if defined(CONFIG_ARCH_HAS_SYNC_DMA_FOR_DEVICE) || \
 624    defined(CONFIG_ARCH_HAS_SYNC_DMA_FOR_CPU) || \
 625    defined(CONFIG_ARCH_HAS_SYNC_DMA_FOR_CPU_ALL)
 626        bool                    dma_coherent:1;
 627#endif
 628};
 629
 630static inline struct device *kobj_to_dev(struct kobject *kobj)
 631{
 632        return container_of(kobj, struct device, kobj);
 633}
 634
 635/**
 636 * device_iommu_mapped - Returns true when the device DMA is translated
 637 *                       by an IOMMU
 638 * @dev: Device to perform the check on
 639 */
 640static inline bool device_iommu_mapped(struct device *dev)
 641{
 642        return (dev->iommu_group != NULL);
 643}
 644
 645/* Get the wakeup routines, which depend on struct device */
 646#include <linux/pm_wakeup.h>
 647
 648static inline const char *dev_name(const struct device *dev)
 649{
 650        /* Use the init name until the kobject becomes available */
 651        if (dev->init_name)
 652                return dev->init_name;
 653
 654        return kobject_name(&dev->kobj);
 655}
 656
 657extern __printf(2, 3)
 658int dev_set_name(struct device *dev, const char *name, ...);
 659
 660#ifdef CONFIG_NUMA
 661static inline int dev_to_node(struct device *dev)
 662{
 663        return dev->numa_node;
 664}
 665static inline void set_dev_node(struct device *dev, int node)
 666{
 667        dev->numa_node = node;
 668}
 669#else
 670static inline int dev_to_node(struct device *dev)
 671{
 672        return NUMA_NO_NODE;
 673}
 674static inline void set_dev_node(struct device *dev, int node)
 675{
 676}
 677#endif
 678
 679static inline struct irq_domain *dev_get_msi_domain(const struct device *dev)
 680{
 681#ifdef CONFIG_GENERIC_MSI_IRQ_DOMAIN
 682        return dev->msi_domain;
 683#else
 684        return NULL;
 685#endif
 686}
 687
 688static inline void dev_set_msi_domain(struct device *dev, struct irq_domain *d)
 689{
 690#ifdef CONFIG_GENERIC_MSI_IRQ_DOMAIN
 691        dev->msi_domain = d;
 692#endif
 693}
 694
 695static inline void *dev_get_drvdata(const struct device *dev)
 696{
 697        return dev->driver_data;
 698}
 699
 700static inline void dev_set_drvdata(struct device *dev, void *data)
 701{
 702        dev->driver_data = data;
 703}
 704
 705static inline struct pm_subsys_data *dev_to_psd(struct device *dev)
 706{
 707        return dev ? dev->power.subsys_data : NULL;
 708}
 709
 710static inline unsigned int dev_get_uevent_suppress(const struct device *dev)
 711{
 712        return dev->kobj.uevent_suppress;
 713}
 714
 715static inline void dev_set_uevent_suppress(struct device *dev, int val)
 716{
 717        dev->kobj.uevent_suppress = val;
 718}
 719
 720static inline int device_is_registered(struct device *dev)
 721{
 722        return dev->kobj.state_in_sysfs;
 723}
 724
 725static inline void device_enable_async_suspend(struct device *dev)
 726{
 727        if (!dev->power.is_prepared)
 728                dev->power.async_suspend = true;
 729}
 730
 731static inline void device_disable_async_suspend(struct device *dev)
 732{
 733        if (!dev->power.is_prepared)
 734                dev->power.async_suspend = false;
 735}
 736
 737static inline bool device_async_suspend_enabled(struct device *dev)
 738{
 739        return !!dev->power.async_suspend;
 740}
 741
 742static inline bool device_pm_not_required(struct device *dev)
 743{
 744        return dev->power.no_pm;
 745}
 746
 747static inline void device_set_pm_not_required(struct device *dev)
 748{
 749        dev->power.no_pm = true;
 750}
 751
 752static inline void dev_pm_syscore_device(struct device *dev, bool val)
 753{
 754#ifdef CONFIG_PM_SLEEP
 755        dev->power.syscore = val;
 756#endif
 757}
 758
 759static inline void dev_pm_set_driver_flags(struct device *dev, u32 flags)
 760{
 761        dev->power.driver_flags = flags;
 762}
 763
 764static inline bool dev_pm_test_driver_flags(struct device *dev, u32 flags)
 765{
 766        return !!(dev->power.driver_flags & flags);
 767}
 768
 769static inline void device_lock(struct device *dev)
 770{
 771        mutex_lock(&dev->mutex);
 772}
 773
 774static inline int device_lock_interruptible(struct device *dev)
 775{
 776        return mutex_lock_interruptible(&dev->mutex);
 777}
 778
 779static inline int device_trylock(struct device *dev)
 780{
 781        return mutex_trylock(&dev->mutex);
 782}
 783
 784static inline void device_unlock(struct device *dev)
 785{
 786        mutex_unlock(&dev->mutex);
 787}
 788
 789static inline void device_lock_assert(struct device *dev)
 790{
 791        lockdep_assert_held(&dev->mutex);
 792}
 793
 794static inline struct device_node *dev_of_node(struct device *dev)
 795{
 796        if (!IS_ENABLED(CONFIG_OF) || !dev)
 797                return NULL;
 798        return dev->of_node;
 799}
 800
 801static inline bool dev_has_sync_state(struct device *dev)
 802{
 803        if (!dev)
 804                return false;
 805        if (dev->driver && dev->driver->sync_state)
 806                return true;
 807        if (dev->bus && dev->bus->sync_state)
 808                return true;
 809        return false;
 810}
 811
 812/*
 813 * High level routines for use by the bus drivers
 814 */
 815extern int __must_check device_register(struct device *dev);
 816extern void device_unregister(struct device *dev);
 817extern void device_initialize(struct device *dev);
 818extern int __must_check device_add(struct device *dev);
 819extern void device_del(struct device *dev);
 820extern int device_for_each_child(struct device *dev, void *data,
 821                     int (*fn)(struct device *dev, void *data));
 822extern int device_for_each_child_reverse(struct device *dev, void *data,
 823                     int (*fn)(struct device *dev, void *data));
 824extern struct device *device_find_child(struct device *dev, void *data,
 825                                int (*match)(struct device *dev, void *data));
 826extern struct device *device_find_child_by_name(struct device *parent,
 827                                                const char *name);
 828extern int device_rename(struct device *dev, const char *new_name);
 829extern int device_move(struct device *dev, struct device *new_parent,
 830                       enum dpm_order dpm_order);
 831extern const char *device_get_devnode(struct device *dev,
 832                                      umode_t *mode, kuid_t *uid, kgid_t *gid,
 833                                      const char **tmp);
 834
 835static inline bool device_supports_offline(struct device *dev)
 836{
 837        return dev->bus && dev->bus->offline && dev->bus->online;
 838}
 839
 840extern void lock_device_hotplug(void);
 841extern void unlock_device_hotplug(void);
 842extern int lock_device_hotplug_sysfs(void);
 843extern int device_offline(struct device *dev);
 844extern int device_online(struct device *dev);
 845extern void set_primary_fwnode(struct device *dev, struct fwnode_handle *fwnode);
 846extern void set_secondary_fwnode(struct device *dev, struct fwnode_handle *fwnode);
 847void device_set_of_node_from_dev(struct device *dev, const struct device *dev2);
 848
 849static inline int dev_num_vf(struct device *dev)
 850{
 851        if (dev->bus && dev->bus->num_vf)
 852                return dev->bus->num_vf(dev);
 853        return 0;
 854}
 855
 856/*
 857 * Root device objects for grouping under /sys/devices
 858 */
 859extern struct device *__root_device_register(const char *name,
 860                                             struct module *owner);
 861
 862/* This is a macro to avoid include problems with THIS_MODULE */
 863#define root_device_register(name) \
 864        __root_device_register(name, THIS_MODULE)
 865
 866extern void root_device_unregister(struct device *root);
 867
 868static inline void *dev_get_platdata(const struct device *dev)
 869{
 870        return dev->platform_data;
 871}
 872
 873/*
 874 * Manual binding of a device to driver. See drivers/base/bus.c
 875 * for information on use.
 876 */
 877extern int __must_check device_bind_driver(struct device *dev);
 878extern void device_release_driver(struct device *dev);
 879extern int  __must_check device_attach(struct device *dev);
 880extern int __must_check driver_attach(struct device_driver *drv);
 881extern void device_initial_probe(struct device *dev);
 882extern int __must_check device_reprobe(struct device *dev);
 883
 884extern bool device_is_bound(struct device *dev);
 885
 886/*
 887 * Easy functions for dynamically creating devices on the fly
 888 */
 889extern __printf(5, 0)
 890struct device *device_create_vargs(struct class *cls, struct device *parent,
 891                                   dev_t devt, void *drvdata,
 892                                   const char *fmt, va_list vargs);
 893extern __printf(5, 6)
 894struct device *device_create(struct class *cls, struct device *parent,
 895                             dev_t devt, void *drvdata,
 896                             const char *fmt, ...);
 897extern __printf(6, 7)
 898struct device *device_create_with_groups(struct class *cls,
 899                             struct device *parent, dev_t devt, void *drvdata,
 900                             const struct attribute_group **groups,
 901                             const char *fmt, ...);
 902extern void device_destroy(struct class *cls, dev_t devt);
 903
 904extern int __must_check device_add_groups(struct device *dev,
 905                                        const struct attribute_group **groups);
 906extern void device_remove_groups(struct device *dev,
 907                                 const struct attribute_group **groups);
 908
 909static inline int __must_check device_add_group(struct device *dev,
 910                                        const struct attribute_group *grp)
 911{
 912        const struct attribute_group *groups[] = { grp, NULL };
 913
 914        return device_add_groups(dev, groups);
 915}
 916
 917static inline void device_remove_group(struct device *dev,
 918                                       const struct attribute_group *grp)
 919{
 920        const struct attribute_group *groups[] = { grp, NULL };
 921
 922        return device_remove_groups(dev, groups);
 923}
 924
 925extern int __must_check devm_device_add_groups(struct device *dev,
 926                                        const struct attribute_group **groups);
 927extern void devm_device_remove_groups(struct device *dev,
 928                                      const struct attribute_group **groups);
 929extern int __must_check devm_device_add_group(struct device *dev,
 930                                        const struct attribute_group *grp);
 931extern void devm_device_remove_group(struct device *dev,
 932                                     const struct attribute_group *grp);
 933
 934/*
 935 * Platform "fixup" functions - allow the platform to have their say
 936 * about devices and actions that the general device layer doesn't
 937 * know about.
 938 */
 939/* Notify platform of device discovery */
 940extern int (*platform_notify)(struct device *dev);
 941
 942extern int (*platform_notify_remove)(struct device *dev);
 943
 944
 945/*
 946 * get_device - atomically increment the reference count for the device.
 947 *
 948 */
 949extern struct device *get_device(struct device *dev);
 950extern void put_device(struct device *dev);
 951extern bool kill_device(struct device *dev);
 952
 953#ifdef CONFIG_DEVTMPFS
 954extern int devtmpfs_mount(void);
 955#else
 956static inline int devtmpfs_mount(void) { return 0; }
 957#endif
 958
 959/* drivers/base/power/shutdown.c */
 960extern void device_shutdown(void);
 961
 962/* debugging and troubleshooting/diagnostic helpers. */
 963extern const char *dev_driver_string(const struct device *dev);
 964
 965/* Device links interface. */
 966struct device_link *device_link_add(struct device *consumer,
 967                                    struct device *supplier, u32 flags);
 968void device_link_del(struct device_link *link);
 969void device_link_remove(void *consumer, struct device *supplier);
 970void device_links_supplier_sync_state_pause(void);
 971void device_links_supplier_sync_state_resume(void);
 972
 973/* Create alias, so I can be autoloaded. */
 974#define MODULE_ALIAS_CHARDEV(major,minor) \
 975        MODULE_ALIAS("char-major-" __stringify(major) "-" __stringify(minor))
 976#define MODULE_ALIAS_CHARDEV_MAJOR(major) \
 977        MODULE_ALIAS("char-major-" __stringify(major) "-*")
 978
 979#ifdef CONFIG_SYSFS_DEPRECATED
 980extern long sysfs_deprecated;
 981#else
 982#define sysfs_deprecated 0
 983#endif
 984
 985#endif /* _DEVICE_H_ */
 986