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/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 <asm/device.h>
  34
  35struct device;
  36struct device_private;
  37struct device_driver;
  38struct driver_private;
  39struct module;
  40struct class;
  41struct subsys_private;
  42struct device_node;
  43struct fwnode_handle;
  44struct iommu_ops;
  45struct iommu_group;
  46struct dev_pin_info;
  47struct dev_iommu;
  48
  49/**
  50 * struct subsys_interface - interfaces to device functions
  51 * @name:       name of the device function
  52 * @subsys:     subsystem 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_ADMIN_RW(_name) \
 133        struct device_attribute dev_attr_##_name = __ATTR_RW_MODE(_name, 0600)
 134#define DEVICE_ATTR_RO(_name) \
 135        struct device_attribute dev_attr_##_name = __ATTR_RO(_name)
 136#define DEVICE_ATTR_ADMIN_RO(_name) \
 137        struct device_attribute dev_attr_##_name = __ATTR_RO_MODE(_name, 0400)
 138#define DEVICE_ATTR_WO(_name) \
 139        struct device_attribute dev_attr_##_name = __ATTR_WO(_name)
 140#define DEVICE_ULONG_ATTR(_name, _mode, _var) \
 141        struct dev_ext_attribute dev_attr_##_name = \
 142                { __ATTR(_name, _mode, device_show_ulong, device_store_ulong), &(_var) }
 143#define DEVICE_INT_ATTR(_name, _mode, _var) \
 144        struct dev_ext_attribute dev_attr_##_name = \
 145                { __ATTR(_name, _mode, device_show_int, device_store_int), &(_var) }
 146#define DEVICE_BOOL_ATTR(_name, _mode, _var) \
 147        struct dev_ext_attribute dev_attr_##_name = \
 148                { __ATTR(_name, _mode, device_show_bool, device_store_bool), &(_var) }
 149#define DEVICE_ATTR_IGNORE_LOCKDEP(_name, _mode, _show, _store) \
 150        struct device_attribute dev_attr_##_name =              \
 151                __ATTR_IGNORE_LOCKDEP(_name, _mode, _show, _store)
 152
 153int device_create_file(struct device *device,
 154                       const struct device_attribute *entry);
 155void device_remove_file(struct device *dev,
 156                        const struct device_attribute *attr);
 157bool device_remove_file_self(struct device *dev,
 158                             const struct device_attribute *attr);
 159int __must_check device_create_bin_file(struct device *dev,
 160                                        const struct bin_attribute *attr);
 161void device_remove_bin_file(struct device *dev,
 162                            const struct bin_attribute *attr);
 163
 164/* device resource management */
 165typedef void (*dr_release_t)(struct device *dev, void *res);
 166typedef int (*dr_match_t)(struct device *dev, void *res, void *match_data);
 167
 168void *__devres_alloc_node(dr_release_t release, size_t size, gfp_t gfp,
 169                          int nid, const char *name) __malloc;
 170#define devres_alloc(release, size, gfp) \
 171        __devres_alloc_node(release, size, gfp, NUMA_NO_NODE, #release)
 172#define devres_alloc_node(release, size, gfp, nid) \
 173        __devres_alloc_node(release, size, gfp, nid, #release)
 174
 175void devres_for_each_res(struct device *dev, dr_release_t release,
 176                         dr_match_t match, void *match_data,
 177                         void (*fn)(struct device *, void *, void *),
 178                         void *data);
 179void devres_free(void *res);
 180void devres_add(struct device *dev, void *res);
 181void *devres_find(struct device *dev, dr_release_t release,
 182                  dr_match_t match, void *match_data);
 183void *devres_get(struct device *dev, void *new_res,
 184                 dr_match_t match, void *match_data);
 185void *devres_remove(struct device *dev, dr_release_t release,
 186                    dr_match_t match, void *match_data);
 187int devres_destroy(struct device *dev, dr_release_t release,
 188                   dr_match_t match, void *match_data);
 189int devres_release(struct device *dev, dr_release_t release,
 190                   dr_match_t match, void *match_data);
 191
 192/* devres group */
 193void * __must_check devres_open_group(struct device *dev, void *id, gfp_t gfp);
 194void devres_close_group(struct device *dev, void *id);
 195void devres_remove_group(struct device *dev, void *id);
 196int devres_release_group(struct device *dev, void *id);
 197
 198/* managed devm_k.alloc/kfree for device drivers */
 199void *devm_kmalloc(struct device *dev, size_t size, gfp_t gfp) __malloc;
 200void *devm_krealloc(struct device *dev, void *ptr, size_t size,
 201                    gfp_t gfp) __must_check;
 202__printf(3, 0) char *devm_kvasprintf(struct device *dev, gfp_t gfp,
 203                                     const char *fmt, va_list ap) __malloc;
 204__printf(3, 4) char *devm_kasprintf(struct device *dev, gfp_t gfp,
 205                                    const char *fmt, ...) __malloc;
 206static inline void *devm_kzalloc(struct device *dev, size_t size, gfp_t gfp)
 207{
 208        return devm_kmalloc(dev, size, gfp | __GFP_ZERO);
 209}
 210static inline void *devm_kmalloc_array(struct device *dev,
 211                                       size_t n, size_t size, gfp_t flags)
 212{
 213        size_t bytes;
 214
 215        if (unlikely(check_mul_overflow(n, size, &bytes)))
 216                return NULL;
 217
 218        return devm_kmalloc(dev, bytes, flags);
 219}
 220static inline void *devm_kcalloc(struct device *dev,
 221                                 size_t n, size_t size, gfp_t flags)
 222{
 223        return devm_kmalloc_array(dev, n, size, flags | __GFP_ZERO);
 224}
 225void devm_kfree(struct device *dev, const void *p);
 226char *devm_kstrdup(struct device *dev, const char *s, gfp_t gfp) __malloc;
 227const char *devm_kstrdup_const(struct device *dev, const char *s, gfp_t gfp);
 228void *devm_kmemdup(struct device *dev, const void *src, size_t len, gfp_t gfp);
 229
 230unsigned long devm_get_free_pages(struct device *dev,
 231                                  gfp_t gfp_mask, unsigned int order);
 232void devm_free_pages(struct device *dev, unsigned long addr);
 233
 234void __iomem *devm_ioremap_resource(struct device *dev,
 235                                    const struct resource *res);
 236void __iomem *devm_ioremap_resource_wc(struct device *dev,
 237                                       const struct resource *res);
 238
 239void __iomem *devm_of_iomap(struct device *dev,
 240                            struct device_node *node, int index,
 241                            resource_size_t *size);
 242
 243/* allows to add/remove a custom action to devres stack */
 244int devm_add_action(struct device *dev, void (*action)(void *), void *data);
 245void devm_remove_action(struct device *dev, void (*action)(void *), void *data);
 246void devm_release_action(struct device *dev, void (*action)(void *), void *data);
 247
 248static inline int devm_add_action_or_reset(struct device *dev,
 249                                           void (*action)(void *), void *data)
 250{
 251        int ret;
 252
 253        ret = devm_add_action(dev, action, data);
 254        if (ret)
 255                action(data);
 256
 257        return ret;
 258}
 259
 260/**
 261 * devm_alloc_percpu - Resource-managed alloc_percpu
 262 * @dev: Device to allocate per-cpu memory for
 263 * @type: Type to allocate per-cpu memory for
 264 *
 265 * Managed alloc_percpu. Per-cpu memory allocated with this function is
 266 * automatically freed on driver detach.
 267 *
 268 * RETURNS:
 269 * Pointer to allocated memory on success, NULL on failure.
 270 */
 271#define devm_alloc_percpu(dev, type)      \
 272        ((typeof(type) __percpu *)__devm_alloc_percpu((dev), sizeof(type), \
 273                                                      __alignof__(type)))
 274
 275void __percpu *__devm_alloc_percpu(struct device *dev, size_t size,
 276                                   size_t align);
 277void devm_free_percpu(struct device *dev, void __percpu *pdata);
 278
 279struct device_dma_parameters {
 280        /*
 281         * a low level driver may set these to teach IOMMU code about
 282         * sg limitations.
 283         */
 284        unsigned int max_segment_size;
 285        unsigned int min_align_mask;
 286        unsigned long segment_boundary_mask;
 287};
 288
 289/**
 290 * enum device_link_state - Device link states.
 291 * @DL_STATE_NONE: The presence of the drivers is not being tracked.
 292 * @DL_STATE_DORMANT: None of the supplier/consumer drivers is present.
 293 * @DL_STATE_AVAILABLE: The supplier driver is present, but the consumer is not.
 294 * @DL_STATE_CONSUMER_PROBE: The consumer is probing (supplier driver present).
 295 * @DL_STATE_ACTIVE: Both the supplier and consumer drivers are present.
 296 * @DL_STATE_SUPPLIER_UNBIND: The supplier driver is unbinding.
 297 */
 298enum device_link_state {
 299        DL_STATE_NONE = -1,
 300        DL_STATE_DORMANT = 0,
 301        DL_STATE_AVAILABLE,
 302        DL_STATE_CONSUMER_PROBE,
 303        DL_STATE_ACTIVE,
 304        DL_STATE_SUPPLIER_UNBIND,
 305};
 306
 307/*
 308 * Device link flags.
 309 *
 310 * STATELESS: The core will not remove this link automatically.
 311 * AUTOREMOVE_CONSUMER: Remove the link automatically on consumer driver unbind.
 312 * PM_RUNTIME: If set, the runtime PM framework will use this link.
 313 * RPM_ACTIVE: Run pm_runtime_get_sync() on the supplier during link creation.
 314 * AUTOREMOVE_SUPPLIER: Remove the link automatically on supplier driver unbind.
 315 * AUTOPROBE_CONSUMER: Probe consumer driver automatically after supplier binds.
 316 * MANAGED: The core tracks presence of supplier/consumer drivers (internal).
 317 * SYNC_STATE_ONLY: Link only affects sync_state() behavior.
 318 * INFERRED: Inferred from data (eg: firmware) and not from driver actions.
 319 */
 320#define DL_FLAG_STATELESS               BIT(0)
 321#define DL_FLAG_AUTOREMOVE_CONSUMER     BIT(1)
 322#define DL_FLAG_PM_RUNTIME              BIT(2)
 323#define DL_FLAG_RPM_ACTIVE              BIT(3)
 324#define DL_FLAG_AUTOREMOVE_SUPPLIER     BIT(4)
 325#define DL_FLAG_AUTOPROBE_CONSUMER      BIT(5)
 326#define DL_FLAG_MANAGED                 BIT(6)
 327#define DL_FLAG_SYNC_STATE_ONLY         BIT(7)
 328#define DL_FLAG_INFERRED                BIT(8)
 329
 330/**
 331 * enum dl_dev_state - Device driver presence tracking information.
 332 * @DL_DEV_NO_DRIVER: There is no driver attached to the device.
 333 * @DL_DEV_PROBING: A driver is probing.
 334 * @DL_DEV_DRIVER_BOUND: The driver has been bound to the device.
 335 * @DL_DEV_UNBINDING: The driver is unbinding from the device.
 336 */
 337enum dl_dev_state {
 338        DL_DEV_NO_DRIVER = 0,
 339        DL_DEV_PROBING,
 340        DL_DEV_DRIVER_BOUND,
 341        DL_DEV_UNBINDING,
 342};
 343
 344/**
 345 * enum device_removable - Whether the device is removable. The criteria for a
 346 * device to be classified as removable is determined by its subsystem or bus.
 347 * @DEVICE_REMOVABLE_NOT_SUPPORTED: This attribute is not supported for this
 348 *                                  device (default).
 349 * @DEVICE_REMOVABLE_UNKNOWN:  Device location is Unknown.
 350 * @DEVICE_FIXED: Device is not removable by the user.
 351 * @DEVICE_REMOVABLE: Device is removable by the user.
 352 */
 353enum device_removable {
 354        DEVICE_REMOVABLE_NOT_SUPPORTED = 0, /* must be 0 */
 355        DEVICE_REMOVABLE_UNKNOWN,
 356        DEVICE_FIXED,
 357        DEVICE_REMOVABLE,
 358};
 359
 360/**
 361 * struct dev_links_info - Device data related to device links.
 362 * @suppliers: List of links to supplier devices.
 363 * @consumers: List of links to consumer devices.
 364 * @defer_sync: Hook to global list of devices that have deferred sync_state.
 365 * @status: Driver status information.
 366 */
 367struct dev_links_info {
 368        struct list_head suppliers;
 369        struct list_head consumers;
 370        struct list_head defer_sync;
 371        enum dl_dev_state status;
 372};
 373
 374/**
 375 * struct device - The basic device structure
 376 * @parent:     The device's "parent" device, the device to which it is attached.
 377 *              In most cases, a parent device is some sort of bus or host
 378 *              controller. If parent is NULL, the device, is a top-level device,
 379 *              which is not usually what you want.
 380 * @p:          Holds the private data of the driver core portions of the device.
 381 *              See the comment of the struct device_private for detail.
 382 * @kobj:       A top-level, abstract class from which other classes are derived.
 383 * @init_name:  Initial name of the device.
 384 * @type:       The type of device.
 385 *              This identifies the device type and carries type-specific
 386 *              information.
 387 * @mutex:      Mutex to synchronize calls to its driver.
 388 * @lockdep_mutex: An optional debug lock that a subsystem can use as a
 389 *              peer lock to gain localized lockdep coverage of the device_lock.
 390 * @bus:        Type of bus device is on.
 391 * @driver:     Which driver has allocated this
 392 * @platform_data: Platform data specific to the device.
 393 *              Example: For devices on custom boards, as typical of embedded
 394 *              and SOC based hardware, Linux often uses platform_data to point
 395 *              to board-specific structures describing devices and how they
 396 *              are wired.  That can include what ports are available, chip
 397 *              variants, which GPIO pins act in what additional roles, and so
 398 *              on.  This shrinks the "Board Support Packages" (BSPs) and
 399 *              minimizes board-specific #ifdefs in drivers.
 400 * @driver_data: Private pointer for driver specific info.
 401 * @links:      Links to suppliers and consumers of this device.
 402 * @power:      For device power management.
 403 *              See Documentation/driver-api/pm/devices.rst for details.
 404 * @pm_domain:  Provide callbacks that are executed during system suspend,
 405 *              hibernation, system resume and during runtime PM transitions
 406 *              along with subsystem-level and driver-level callbacks.
 407 * @em_pd:      device's energy model performance domain
 408 * @pins:       For device pin management.
 409 *              See Documentation/driver-api/pin-control.rst for details.
 410 * @msi_lock:   Lock to protect MSI mask cache and mask register
 411 * @msi_list:   Hosts MSI descriptors
 412 * @msi_domain: The generic MSI domain this device is using.
 413 * @numa_node:  NUMA node this device is close to.
 414 * @dma_ops:    DMA mapping operations for this device.
 415 * @dma_mask:   Dma mask (if dma'ble device).
 416 * @coherent_dma_mask: Like dma_mask, but for alloc_coherent mapping as not all
 417 *              hardware supports 64-bit addresses for consistent allocations
 418 *              such descriptors.
 419 * @bus_dma_limit: Limit of an upstream bridge or bus which imposes a smaller
 420 *              DMA limit than the device itself supports.
 421 * @dma_range_map: map for DMA memory ranges relative to that of RAM
 422 * @dma_parms:  A low level driver may set these to teach IOMMU code about
 423 *              segment limitations.
 424 * @dma_pools:  Dma pools (if dma'ble device).
 425 * @dma_mem:    Internal for coherent mem override.
 426 * @cma_area:   Contiguous memory area for dma allocations
 427 * @archdata:   For arch-specific additions.
 428 * @of_node:    Associated device tree node.
 429 * @fwnode:     Associated device node supplied by platform firmware.
 430 * @devt:       For creating the sysfs "dev".
 431 * @id:         device instance
 432 * @devres_lock: Spinlock to protect the resource of the device.
 433 * @devres_head: The resources list of the device.
 434 * @knode_class: The node used to add the device to the class list.
 435 * @class:      The class of the device.
 436 * @groups:     Optional attribute groups.
 437 * @release:    Callback to free the device after all references have
 438 *              gone away. This should be set by the allocator of the
 439 *              device (i.e. the bus driver that discovered the device).
 440 * @iommu_group: IOMMU group the device belongs to.
 441 * @iommu:      Per device generic IOMMU runtime data
 442 * @removable:  Whether the device can be removed from the system. This
 443 *              should be set by the subsystem / bus driver that discovered
 444 *              the device.
 445 *
 446 * @offline_disabled: If set, the device is permanently online.
 447 * @offline:    Set after successful invocation of bus type's .offline().
 448 * @of_node_reused: Set if the device-tree node is shared with an ancestor
 449 *              device.
 450 * @state_synced: The hardware state of this device has been synced to match
 451 *                the software state of this device by calling the driver/bus
 452 *                sync_state() callback.
 453 * @can_match:  The device has matched with a driver at least once or it is in
 454 *              a bus (like AMBA) which can't check for matching drivers until
 455 *              other devices probe successfully.
 456 * @dma_coherent: this particular device is dma coherent, even if the
 457 *              architecture supports non-coherent devices.
 458 * @dma_ops_bypass: If set to %true then the dma_ops are bypassed for the
 459 *              streaming DMA operations (->map_* / ->unmap_* / ->sync_*),
 460 *              and optionall (if the coherent mask is large enough) also
 461 *              for dma allocations.  This flag is managed by the dma ops
 462 *              instance from ->dma_supported.
 463 *
 464 * At the lowest level, every device in a Linux system is represented by an
 465 * instance of struct device. The device structure contains the information
 466 * that the device model core needs to model the system. Most subsystems,
 467 * however, track additional information about the devices they host. As a
 468 * result, it is rare for devices to be represented by bare device structures;
 469 * instead, that structure, like kobject structures, is usually embedded within
 470 * a higher-level representation of the device.
 471 */
 472struct device {
 473        struct kobject kobj;
 474        struct device           *parent;
 475
 476        struct device_private   *p;
 477
 478        const char              *init_name; /* initial name of the device */
 479        const struct device_type *type;
 480
 481        struct bus_type *bus;           /* type of bus device is on */
 482        struct device_driver *driver;   /* which driver has allocated this
 483                                           device */
 484        void            *platform_data; /* Platform specific data, device
 485                                           core doesn't touch it */
 486        void            *driver_data;   /* Driver data, set and get with
 487                                           dev_set_drvdata/dev_get_drvdata */
 488#ifdef CONFIG_PROVE_LOCKING
 489        struct mutex            lockdep_mutex;
 490#endif
 491        struct mutex            mutex;  /* mutex to synchronize calls to
 492                                         * its driver.
 493                                         */
 494
 495        struct dev_links_info   links;
 496        struct dev_pm_info      power;
 497        struct dev_pm_domain    *pm_domain;
 498
 499#ifdef CONFIG_ENERGY_MODEL
 500        struct em_perf_domain   *em_pd;
 501#endif
 502
 503#ifdef CONFIG_GENERIC_MSI_IRQ_DOMAIN
 504        struct irq_domain       *msi_domain;
 505#endif
 506#ifdef CONFIG_PINCTRL
 507        struct dev_pin_info     *pins;
 508#endif
 509#ifdef CONFIG_GENERIC_MSI_IRQ
 510        raw_spinlock_t          msi_lock;
 511        struct list_head        msi_list;
 512#endif
 513#ifdef CONFIG_DMA_OPS
 514        const struct dma_map_ops *dma_ops;
 515#endif
 516        u64             *dma_mask;      /* dma mask (if dma'able device) */
 517        u64             coherent_dma_mask;/* Like dma_mask, but for
 518                                             alloc_coherent mappings as
 519                                             not all hardware supports
 520                                             64 bit addresses for consistent
 521                                             allocations such descriptors. */
 522        u64             bus_dma_limit;  /* upstream dma constraint */
 523        const struct bus_dma_region *dma_range_map;
 524
 525        struct device_dma_parameters *dma_parms;
 526
 527        struct list_head        dma_pools;      /* dma pools (if dma'ble) */
 528
 529#ifdef CONFIG_DMA_DECLARE_COHERENT
 530        struct dma_coherent_mem *dma_mem; /* internal for coherent mem
 531                                             override */
 532#endif
 533#ifdef CONFIG_DMA_CMA
 534        struct cma *cma_area;           /* contiguous memory area for dma
 535                                           allocations */
 536#endif
 537        /* arch specific additions */
 538        struct dev_archdata     archdata;
 539
 540        struct device_node      *of_node; /* associated device tree node */
 541        struct fwnode_handle    *fwnode; /* firmware device node */
 542
 543#ifdef CONFIG_NUMA
 544        int             numa_node;      /* NUMA node this device is close to */
 545#endif
 546        dev_t                   devt;   /* dev_t, creates the sysfs "dev" */
 547        u32                     id;     /* device instance */
 548
 549        spinlock_t              devres_lock;
 550        struct list_head        devres_head;
 551
 552        struct class            *class;
 553        const struct attribute_group **groups;  /* optional groups */
 554
 555        void    (*release)(struct device *dev);
 556        struct iommu_group      *iommu_group;
 557        struct dev_iommu        *iommu;
 558
 559        enum device_removable   removable;
 560
 561        bool                    offline_disabled:1;
 562        bool                    offline:1;
 563        bool                    of_node_reused:1;
 564        bool                    state_synced:1;
 565        bool                    can_match:1;
 566#if defined(CONFIG_ARCH_HAS_SYNC_DMA_FOR_DEVICE) || \
 567    defined(CONFIG_ARCH_HAS_SYNC_DMA_FOR_CPU) || \
 568    defined(CONFIG_ARCH_HAS_SYNC_DMA_FOR_CPU_ALL)
 569        bool                    dma_coherent:1;
 570#endif
 571#ifdef CONFIG_DMA_OPS_BYPASS
 572        bool                    dma_ops_bypass : 1;
 573#endif
 574};
 575
 576/**
 577 * struct device_link - Device link representation.
 578 * @supplier: The device on the supplier end of the link.
 579 * @s_node: Hook to the supplier device's list of links to consumers.
 580 * @consumer: The device on the consumer end of the link.
 581 * @c_node: Hook to the consumer device's list of links to suppliers.
 582 * @link_dev: device used to expose link details in sysfs
 583 * @status: The state of the link (with respect to the presence of drivers).
 584 * @flags: Link flags.
 585 * @rpm_active: Whether or not the consumer device is runtime-PM-active.
 586 * @kref: Count repeated addition of the same link.
 587 * @rm_work: Work structure used for removing the link.
 588 * @supplier_preactivated: Supplier has been made active before consumer probe.
 589 */
 590struct device_link {
 591        struct device *supplier;
 592        struct list_head s_node;
 593        struct device *consumer;
 594        struct list_head c_node;
 595        struct device link_dev;
 596        enum device_link_state status;
 597        u32 flags;
 598        refcount_t rpm_active;
 599        struct kref kref;
 600        struct work_struct rm_work;
 601        bool supplier_preactivated; /* Owned by consumer probe. */
 602};
 603
 604static inline struct device *kobj_to_dev(struct kobject *kobj)
 605{
 606        return container_of(kobj, struct device, kobj);
 607}
 608
 609/**
 610 * device_iommu_mapped - Returns true when the device DMA is translated
 611 *                       by an IOMMU
 612 * @dev: Device to perform the check on
 613 */
 614static inline bool device_iommu_mapped(struct device *dev)
 615{
 616        return (dev->iommu_group != NULL);
 617}
 618
 619/* Get the wakeup routines, which depend on struct device */
 620#include <linux/pm_wakeup.h>
 621
 622static inline const char *dev_name(const struct device *dev)
 623{
 624        /* Use the init name until the kobject becomes available */
 625        if (dev->init_name)
 626                return dev->init_name;
 627
 628        return kobject_name(&dev->kobj);
 629}
 630
 631/**
 632 * dev_bus_name - Return a device's bus/class name, if at all possible
 633 * @dev: struct device to get the bus/class name of
 634 *
 635 * Will return the name of the bus/class the device is attached to.  If it is
 636 * not attached to a bus/class, an empty string will be returned.
 637 */
 638static inline const char *dev_bus_name(const struct device *dev)
 639{
 640        return dev->bus ? dev->bus->name : (dev->class ? dev->class->name : "");
 641}
 642
 643__printf(2, 3) int dev_set_name(struct device *dev, const char *name, ...);
 644
 645#ifdef CONFIG_NUMA
 646static inline int dev_to_node(struct device *dev)
 647{
 648        return dev->numa_node;
 649}
 650static inline void set_dev_node(struct device *dev, int node)
 651{
 652        dev->numa_node = node;
 653}
 654#else
 655static inline int dev_to_node(struct device *dev)
 656{
 657        return NUMA_NO_NODE;
 658}
 659static inline void set_dev_node(struct device *dev, int node)
 660{
 661}
 662#endif
 663
 664static inline struct irq_domain *dev_get_msi_domain(const struct device *dev)
 665{
 666#ifdef CONFIG_GENERIC_MSI_IRQ_DOMAIN
 667        return dev->msi_domain;
 668#else
 669        return NULL;
 670#endif
 671}
 672
 673static inline void dev_set_msi_domain(struct device *dev, struct irq_domain *d)
 674{
 675#ifdef CONFIG_GENERIC_MSI_IRQ_DOMAIN
 676        dev->msi_domain = d;
 677#endif
 678}
 679
 680static inline void *dev_get_drvdata(const struct device *dev)
 681{
 682        return dev->driver_data;
 683}
 684
 685static inline void dev_set_drvdata(struct device *dev, void *data)
 686{
 687        dev->driver_data = data;
 688}
 689
 690static inline struct pm_subsys_data *dev_to_psd(struct device *dev)
 691{
 692        return dev ? dev->power.subsys_data : NULL;
 693}
 694
 695static inline unsigned int dev_get_uevent_suppress(const struct device *dev)
 696{
 697        return dev->kobj.uevent_suppress;
 698}
 699
 700static inline void dev_set_uevent_suppress(struct device *dev, int val)
 701{
 702        dev->kobj.uevent_suppress = val;
 703}
 704
 705static inline int device_is_registered(struct device *dev)
 706{
 707        return dev->kobj.state_in_sysfs;
 708}
 709
 710static inline void device_enable_async_suspend(struct device *dev)
 711{
 712        if (!dev->power.is_prepared)
 713                dev->power.async_suspend = true;
 714}
 715
 716static inline void device_disable_async_suspend(struct device *dev)
 717{
 718        if (!dev->power.is_prepared)
 719                dev->power.async_suspend = false;
 720}
 721
 722static inline bool device_async_suspend_enabled(struct device *dev)
 723{
 724        return !!dev->power.async_suspend;
 725}
 726
 727static inline bool device_pm_not_required(struct device *dev)
 728{
 729        return dev->power.no_pm;
 730}
 731
 732static inline void device_set_pm_not_required(struct device *dev)
 733{
 734        dev->power.no_pm = true;
 735}
 736
 737static inline void dev_pm_syscore_device(struct device *dev, bool val)
 738{
 739#ifdef CONFIG_PM_SLEEP
 740        dev->power.syscore = val;
 741#endif
 742}
 743
 744static inline void dev_pm_set_driver_flags(struct device *dev, u32 flags)
 745{
 746        dev->power.driver_flags = flags;
 747}
 748
 749static inline bool dev_pm_test_driver_flags(struct device *dev, u32 flags)
 750{
 751        return !!(dev->power.driver_flags & flags);
 752}
 753
 754static inline void device_lock(struct device *dev)
 755{
 756        mutex_lock(&dev->mutex);
 757}
 758
 759static inline int device_lock_interruptible(struct device *dev)
 760{
 761        return mutex_lock_interruptible(&dev->mutex);
 762}
 763
 764static inline int device_trylock(struct device *dev)
 765{
 766        return mutex_trylock(&dev->mutex);
 767}
 768
 769static inline void device_unlock(struct device *dev)
 770{
 771        mutex_unlock(&dev->mutex);
 772}
 773
 774static inline void device_lock_assert(struct device *dev)
 775{
 776        lockdep_assert_held(&dev->mutex);
 777}
 778
 779static inline struct device_node *dev_of_node(struct device *dev)
 780{
 781        if (!IS_ENABLED(CONFIG_OF) || !dev)
 782                return NULL;
 783        return dev->of_node;
 784}
 785
 786static inline bool dev_has_sync_state(struct device *dev)
 787{
 788        if (!dev)
 789                return false;
 790        if (dev->driver && dev->driver->sync_state)
 791                return true;
 792        if (dev->bus && dev->bus->sync_state)
 793                return true;
 794        return false;
 795}
 796
 797static inline void dev_set_removable(struct device *dev,
 798                                     enum device_removable removable)
 799{
 800        dev->removable = removable;
 801}
 802
 803static inline bool dev_is_removable(struct device *dev)
 804{
 805        return dev->removable == DEVICE_REMOVABLE;
 806}
 807
 808static inline bool dev_removable_is_valid(struct device *dev)
 809{
 810        return dev->removable != DEVICE_REMOVABLE_NOT_SUPPORTED;
 811}
 812
 813/*
 814 * High level routines for use by the bus drivers
 815 */
 816int __must_check device_register(struct device *dev);
 817void device_unregister(struct device *dev);
 818void device_initialize(struct device *dev);
 819int __must_check device_add(struct device *dev);
 820void device_del(struct device *dev);
 821int device_for_each_child(struct device *dev, void *data,
 822                          int (*fn)(struct device *dev, void *data));
 823int device_for_each_child_reverse(struct device *dev, void *data,
 824                                  int (*fn)(struct device *dev, void *data));
 825struct device *device_find_child(struct device *dev, void *data,
 826                                 int (*match)(struct device *dev, void *data));
 827struct device *device_find_child_by_name(struct device *parent,
 828                                         const char *name);
 829int device_rename(struct device *dev, const char *new_name);
 830int device_move(struct device *dev, struct device *new_parent,
 831                enum dpm_order dpm_order);
 832int device_change_owner(struct device *dev, kuid_t kuid, kgid_t kgid);
 833const char *device_get_devnode(struct device *dev, umode_t *mode, kuid_t *uid,
 834                               kgid_t *gid, const char **tmp);
 835int device_is_dependent(struct device *dev, void *target);
 836
 837static inline bool device_supports_offline(struct device *dev)
 838{
 839        return dev->bus && dev->bus->offline && dev->bus->online;
 840}
 841
 842void lock_device_hotplug(void);
 843void unlock_device_hotplug(void);
 844int lock_device_hotplug_sysfs(void);
 845int device_offline(struct device *dev);
 846int device_online(struct device *dev);
 847void set_primary_fwnode(struct device *dev, struct fwnode_handle *fwnode);
 848void set_secondary_fwnode(struct device *dev, struct fwnode_handle *fwnode);
 849void device_set_of_node_from_dev(struct device *dev, const struct device *dev2);
 850void device_set_node(struct device *dev, struct fwnode_handle *fwnode);
 851
 852static inline int dev_num_vf(struct device *dev)
 853{
 854        if (dev->bus && dev->bus->num_vf)
 855                return dev->bus->num_vf(dev);
 856        return 0;
 857}
 858
 859/*
 860 * Root device objects for grouping under /sys/devices
 861 */
 862struct device *__root_device_register(const char *name, struct module *owner);
 863
 864/* This is a macro to avoid include problems with THIS_MODULE */
 865#define root_device_register(name) \
 866        __root_device_register(name, THIS_MODULE)
 867
 868void root_device_unregister(struct device *root);
 869
 870static inline void *dev_get_platdata(const struct device *dev)
 871{
 872        return dev->platform_data;
 873}
 874
 875/*
 876 * Manual binding of a device to driver. See drivers/base/bus.c
 877 * for information on use.
 878 */
 879int __must_check device_driver_attach(struct device_driver *drv,
 880                                      struct device *dev);
 881int __must_check device_bind_driver(struct device *dev);
 882void device_release_driver(struct device *dev);
 883int  __must_check device_attach(struct device *dev);
 884int __must_check driver_attach(struct device_driver *drv);
 885void device_initial_probe(struct device *dev);
 886int __must_check device_reprobe(struct device *dev);
 887
 888bool device_is_bound(struct device *dev);
 889
 890/*
 891 * Easy functions for dynamically creating devices on the fly
 892 */
 893__printf(5, 6) struct device *
 894device_create(struct class *cls, struct device *parent, dev_t devt,
 895              void *drvdata, const char *fmt, ...);
 896__printf(6, 7) struct device *
 897device_create_with_groups(struct class *cls, struct device *parent, dev_t devt,
 898                          void *drvdata, const struct attribute_group **groups,
 899                          const char *fmt, ...);
 900void device_destroy(struct class *cls, dev_t devt);
 901
 902int __must_check device_add_groups(struct device *dev,
 903                                   const struct attribute_group **groups);
 904void device_remove_groups(struct device *dev,
 905                          const struct attribute_group **groups);
 906
 907static inline int __must_check device_add_group(struct device *dev,
 908                                        const struct attribute_group *grp)
 909{
 910        const struct attribute_group *groups[] = { grp, NULL };
 911
 912        return device_add_groups(dev, groups);
 913}
 914
 915static inline void device_remove_group(struct device *dev,
 916                                       const struct attribute_group *grp)
 917{
 918        const struct attribute_group *groups[] = { grp, NULL };
 919
 920        return device_remove_groups(dev, groups);
 921}
 922
 923int __must_check devm_device_add_groups(struct device *dev,
 924                                        const struct attribute_group **groups);
 925void devm_device_remove_groups(struct device *dev,
 926                               const struct attribute_group **groups);
 927int __must_check devm_device_add_group(struct device *dev,
 928                                       const struct attribute_group *grp);
 929void devm_device_remove_group(struct device *dev,
 930                              const struct attribute_group *grp);
 931
 932/*
 933 * Platform "fixup" functions - allow the platform to have their say
 934 * about devices and actions that the general device layer doesn't
 935 * know about.
 936 */
 937/* Notify platform of device discovery */
 938extern int (*platform_notify)(struct device *dev);
 939
 940extern int (*platform_notify_remove)(struct device *dev);
 941
 942
 943/*
 944 * get_device - atomically increment the reference count for the device.
 945 *
 946 */
 947struct device *get_device(struct device *dev);
 948void put_device(struct device *dev);
 949bool kill_device(struct device *dev);
 950
 951#ifdef CONFIG_DEVTMPFS
 952int devtmpfs_mount(void);
 953#else
 954static inline int devtmpfs_mount(void) { return 0; }
 955#endif
 956
 957/* drivers/base/power/shutdown.c */
 958void device_shutdown(void);
 959
 960/* debugging and troubleshooting/diagnostic helpers. */
 961const char *dev_driver_string(const struct device *dev);
 962
 963/* Device links interface. */
 964struct device_link *device_link_add(struct device *consumer,
 965                                    struct device *supplier, u32 flags);
 966void device_link_del(struct device_link *link);
 967void device_link_remove(void *consumer, struct device *supplier);
 968void device_links_supplier_sync_state_pause(void);
 969void device_links_supplier_sync_state_resume(void);
 970
 971extern __printf(3, 4)
 972int dev_err_probe(const struct device *dev, int err, const char *fmt, ...);
 973
 974/* Create alias, so I can be autoloaded. */
 975#define MODULE_ALIAS_CHARDEV(major,minor) \
 976        MODULE_ALIAS("char-major-" __stringify(major) "-" __stringify(minor))
 977#define MODULE_ALIAS_CHARDEV_MAJOR(major) \
 978        MODULE_ALIAS("char-major-" __stringify(major) "-*")
 979
 980#ifdef CONFIG_SYSFS_DEPRECATED
 981extern long sysfs_deprecated;
 982#else
 983#define sysfs_deprecated 0
 984#endif
 985
 986#endif /* _DEVICE_H_ */
 987