1 // SPDX-License-Identifier: GPL-2.0
3 * device.h - generic, centralized driver model
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.
9 * See Documentation/driver-api/driver-model/ for more information.
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>
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>
36 struct device_private;
38 struct driver_private;
41 struct subsys_private;
48 struct msi_device_data;
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
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.
63 struct subsys_interface {
65 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);
71 int subsys_interface_register(struct subsys_interface *sif);
72 void subsys_interface_unregister(struct subsys_interface *sif);
74 int subsys_system_register(struct bus_type *subsys,
75 const struct attribute_group **groups);
76 int subsys_virtual_register(struct bus_type *subsys,
77 const struct attribute_group **groups);
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.
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);
96 const struct dev_pm_ops *pm;
100 * struct device_attribute - Interface for exporting device attributes.
101 * @attr: sysfs attribute definition.
102 * @show: Show handler.
103 * @store: Store handler.
105 struct device_attribute {
106 struct attribute attr;
107 ssize_t (*show)(struct device *dev, struct device_attribute *attr,
109 ssize_t (*store)(struct device *dev, struct device_attribute *attr,
110 const char *buf, size_t count);
114 * struct dev_ext_attribute - Exported device attribute with extra context.
115 * @attr: Exported device attribute.
116 * @var: Pointer to context.
118 struct dev_ext_attribute {
119 struct device_attribute attr;
123 ssize_t device_show_ulong(struct device *dev, struct device_attribute *attr,
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,
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,
133 ssize_t device_store_bool(struct device *dev, struct device_attribute *attr,
134 const char *buf, size_t count);
137 * DEVICE_ATTR - Define a device attribute.
138 * @_name: Attribute name.
140 * @_show: Show handler. Optional, but mandatory if attribute is readable.
141 * @_store: Store handler. Optional, but mandatory if attribute is writable.
143 * Convenience macro for defining a struct device_attribute.
145 * For example, ``DEVICE_ATTR(foo, 0644, foo_show, foo_store);`` expands to:
149 * struct device_attribute dev_attr_foo = {
150 * .attr = { .name = "foo", .mode = 0644 },
152 * .store = foo_store,
155 #define DEVICE_ATTR(_name, _mode, _show, _store) \
156 struct device_attribute dev_attr_##_name = __ATTR(_name, _mode, _show, _store)
159 * DEVICE_ATTR_PREALLOC - Define a preallocated device attribute.
160 * @_name: Attribute name.
162 * @_show: Show handler. Optional, but mandatory if attribute is readable.
163 * @_store: Store handler. Optional, but mandatory if attribute is writable.
165 * Like DEVICE_ATTR(), but ``SYSFS_PREALLOC`` is set on @_mode.
167 #define DEVICE_ATTR_PREALLOC(_name, _mode, _show, _store) \
168 struct device_attribute dev_attr_##_name = \
169 __ATTR_PREALLOC(_name, _mode, _show, _store)
172 * DEVICE_ATTR_RW - Define a read-write device attribute.
173 * @_name: Attribute name.
175 * Like DEVICE_ATTR(), but @_mode is 0644, @_show is <_name>_show,
176 * and @_store is <_name>_store.
178 #define DEVICE_ATTR_RW(_name) \
179 struct device_attribute dev_attr_##_name = __ATTR_RW(_name)
182 * DEVICE_ATTR_ADMIN_RW - Define an admin-only read-write device attribute.
183 * @_name: Attribute name.
185 * Like DEVICE_ATTR_RW(), but @_mode is 0600.
187 #define DEVICE_ATTR_ADMIN_RW(_name) \
188 struct device_attribute dev_attr_##_name = __ATTR_RW_MODE(_name, 0600)
191 * DEVICE_ATTR_RO - Define a readable device attribute.
192 * @_name: Attribute name.
194 * Like DEVICE_ATTR(), but @_mode is 0444 and @_show is <_name>_show.
196 #define DEVICE_ATTR_RO(_name) \
197 struct device_attribute dev_attr_##_name = __ATTR_RO(_name)
200 * DEVICE_ATTR_ADMIN_RO - Define an admin-only readable device attribute.
201 * @_name: Attribute name.
203 * Like DEVICE_ATTR_RO(), but @_mode is 0400.
205 #define DEVICE_ATTR_ADMIN_RO(_name) \
206 struct device_attribute dev_attr_##_name = __ATTR_RO_MODE(_name, 0400)
209 * DEVICE_ATTR_WO - Define an admin-only writable device attribute.
210 * @_name: Attribute name.
212 * Like DEVICE_ATTR(), but @_mode is 0200 and @_store is <_name>_store.
214 #define DEVICE_ATTR_WO(_name) \
215 struct device_attribute dev_attr_##_name = __ATTR_WO(_name)
218 * DEVICE_ULONG_ATTR - Define a device attribute backed by an unsigned long.
219 * @_name: Attribute name.
221 * @_var: Identifier of unsigned long.
223 * Like DEVICE_ATTR(), but @_show and @_store are automatically provided
224 * such that reads and writes to the attribute from userspace affect @_var.
226 #define DEVICE_ULONG_ATTR(_name, _mode, _var) \
227 struct dev_ext_attribute dev_attr_##_name = \
228 { __ATTR(_name, _mode, device_show_ulong, device_store_ulong), &(_var) }
231 * DEVICE_INT_ATTR - Define a device attribute backed by an int.
232 * @_name: Attribute name.
234 * @_var: Identifier of int.
236 * Like DEVICE_ULONG_ATTR(), but @_var is an int.
238 #define DEVICE_INT_ATTR(_name, _mode, _var) \
239 struct dev_ext_attribute dev_attr_##_name = \
240 { __ATTR(_name, _mode, device_show_int, device_store_int), &(_var) }
243 * DEVICE_BOOL_ATTR - Define a device attribute backed by a bool.
244 * @_name: Attribute name.
246 * @_var: Identifier of bool.
248 * Like DEVICE_ULONG_ATTR(), but @_var is a bool.
250 #define DEVICE_BOOL_ATTR(_name, _mode, _var) \
251 struct dev_ext_attribute dev_attr_##_name = \
252 { __ATTR(_name, _mode, device_show_bool, device_store_bool), &(_var) }
254 #define DEVICE_ATTR_IGNORE_LOCKDEP(_name, _mode, _show, _store) \
255 struct device_attribute dev_attr_##_name = \
256 __ATTR_IGNORE_LOCKDEP(_name, _mode, _show, _store)
258 int device_create_file(struct device *device,
259 const struct device_attribute *entry);
260 void device_remove_file(struct device *dev,
261 const struct device_attribute *attr);
262 bool device_remove_file_self(struct device *dev,
263 const struct device_attribute *attr);
264 int __must_check device_create_bin_file(struct device *dev,
265 const struct bin_attribute *attr);
266 void device_remove_bin_file(struct device *dev,
267 const struct bin_attribute *attr);
269 /* device resource management */
270 typedef void (*dr_release_t)(struct device *dev, void *res);
271 typedef int (*dr_match_t)(struct device *dev, void *res, void *match_data);
273 void *__devres_alloc_node(dr_release_t release, size_t size, gfp_t gfp,
274 int nid, const char *name) __malloc;
275 #define devres_alloc(release, size, gfp) \
276 __devres_alloc_node(release, size, gfp, NUMA_NO_NODE, #release)
277 #define devres_alloc_node(release, size, gfp, nid) \
278 __devres_alloc_node(release, size, gfp, nid, #release)
280 void devres_for_each_res(struct device *dev, dr_release_t release,
281 dr_match_t match, void *match_data,
282 void (*fn)(struct device *, void *, void *),
284 void devres_free(void *res);
285 void devres_add(struct device *dev, void *res);
286 void *devres_find(struct device *dev, dr_release_t release,
287 dr_match_t match, void *match_data);
288 void *devres_get(struct device *dev, void *new_res,
289 dr_match_t match, void *match_data);
290 void *devres_remove(struct device *dev, dr_release_t release,
291 dr_match_t match, void *match_data);
292 int devres_destroy(struct device *dev, dr_release_t release,
293 dr_match_t match, void *match_data);
294 int devres_release(struct device *dev, dr_release_t release,
295 dr_match_t match, void *match_data);
298 void * __must_check devres_open_group(struct device *dev, void *id, gfp_t gfp);
299 void devres_close_group(struct device *dev, void *id);
300 void devres_remove_group(struct device *dev, void *id);
301 int devres_release_group(struct device *dev, void *id);
303 /* managed devm_k.alloc/kfree for device drivers */
304 void *devm_kmalloc(struct device *dev, size_t size, gfp_t gfp) __alloc_size(2);
305 void *devm_krealloc(struct device *dev, void *ptr, size_t size,
306 gfp_t gfp) __must_check __realloc_size(3);
307 __printf(3, 0) char *devm_kvasprintf(struct device *dev, gfp_t gfp,
308 const char *fmt, va_list ap) __malloc;
309 __printf(3, 4) char *devm_kasprintf(struct device *dev, gfp_t gfp,
310 const char *fmt, ...) __malloc;
311 static inline void *devm_kzalloc(struct device *dev, size_t size, gfp_t gfp)
313 return devm_kmalloc(dev, size, gfp | __GFP_ZERO);
315 static inline void *devm_kmalloc_array(struct device *dev,
316 size_t n, size_t size, gfp_t flags)
320 if (unlikely(check_mul_overflow(n, size, &bytes)))
323 return devm_kmalloc(dev, bytes, flags);
325 static inline void *devm_kcalloc(struct device *dev,
326 size_t n, size_t size, gfp_t flags)
328 return devm_kmalloc_array(dev, n, size, flags | __GFP_ZERO);
330 static inline __realloc_size(3, 4) void * __must_check
331 devm_krealloc_array(struct device *dev, void *p, size_t new_n, size_t new_size, gfp_t flags)
335 if (unlikely(check_mul_overflow(new_n, new_size, &bytes)))
338 return devm_krealloc(dev, p, bytes, flags);
341 void devm_kfree(struct device *dev, const void *p);
342 char *devm_kstrdup(struct device *dev, const char *s, gfp_t gfp) __malloc;
343 const char *devm_kstrdup_const(struct device *dev, const char *s, gfp_t gfp);
344 void *devm_kmemdup(struct device *dev, const void *src, size_t len, gfp_t gfp)
347 unsigned long devm_get_free_pages(struct device *dev,
348 gfp_t gfp_mask, unsigned int order);
349 void devm_free_pages(struct device *dev, unsigned long addr);
351 void __iomem *devm_ioremap_resource(struct device *dev,
352 const struct resource *res);
353 void __iomem *devm_ioremap_resource_wc(struct device *dev,
354 const struct resource *res);
356 void __iomem *devm_of_iomap(struct device *dev,
357 struct device_node *node, int index,
358 resource_size_t *size);
360 /* allows to add/remove a custom action to devres stack */
361 void devm_remove_action(struct device *dev, void (*action)(void *), void *data);
362 void devm_release_action(struct device *dev, void (*action)(void *), void *data);
364 int __devm_add_action(struct device *dev, void (*action)(void *), void *data, const char *name);
365 #define devm_add_action(release, action, data) \
366 __devm_add_action(release, action, data, #action)
368 static inline int __devm_add_action_or_reset(struct device *dev, void (*action)(void *),
369 void *data, const char *name)
373 ret = __devm_add_action(dev, action, data, name);
379 #define devm_add_action_or_reset(release, action, data) \
380 __devm_add_action_or_reset(release, action, data, #action)
383 * devm_alloc_percpu - Resource-managed alloc_percpu
384 * @dev: Device to allocate per-cpu memory for
385 * @type: Type to allocate per-cpu memory for
387 * Managed alloc_percpu. Per-cpu memory allocated with this function is
388 * automatically freed on driver detach.
391 * Pointer to allocated memory on success, NULL on failure.
393 #define devm_alloc_percpu(dev, type) \
394 ((typeof(type) __percpu *)__devm_alloc_percpu((dev), sizeof(type), \
397 void __percpu *__devm_alloc_percpu(struct device *dev, size_t size,
399 void devm_free_percpu(struct device *dev, void __percpu *pdata);
401 struct device_dma_parameters {
403 * a low level driver may set these to teach IOMMU code about
406 unsigned int max_segment_size;
407 unsigned int min_align_mask;
408 unsigned long segment_boundary_mask;
412 * enum device_link_state - Device link states.
413 * @DL_STATE_NONE: The presence of the drivers is not being tracked.
414 * @DL_STATE_DORMANT: None of the supplier/consumer drivers is present.
415 * @DL_STATE_AVAILABLE: The supplier driver is present, but the consumer is not.
416 * @DL_STATE_CONSUMER_PROBE: The consumer is probing (supplier driver present).
417 * @DL_STATE_ACTIVE: Both the supplier and consumer drivers are present.
418 * @DL_STATE_SUPPLIER_UNBIND: The supplier driver is unbinding.
420 enum device_link_state {
422 DL_STATE_DORMANT = 0,
424 DL_STATE_CONSUMER_PROBE,
426 DL_STATE_SUPPLIER_UNBIND,
432 * STATELESS: The core will not remove this link automatically.
433 * AUTOREMOVE_CONSUMER: Remove the link automatically on consumer driver unbind.
434 * PM_RUNTIME: If set, the runtime PM framework will use this link.
435 * RPM_ACTIVE: Run pm_runtime_get_sync() on the supplier during link creation.
436 * AUTOREMOVE_SUPPLIER: Remove the link automatically on supplier driver unbind.
437 * AUTOPROBE_CONSUMER: Probe consumer driver automatically after supplier binds.
438 * MANAGED: The core tracks presence of supplier/consumer drivers (internal).
439 * SYNC_STATE_ONLY: Link only affects sync_state() behavior.
440 * INFERRED: Inferred from data (eg: firmware) and not from driver actions.
442 #define DL_FLAG_STATELESS BIT(0)
443 #define DL_FLAG_AUTOREMOVE_CONSUMER BIT(1)
444 #define DL_FLAG_PM_RUNTIME BIT(2)
445 #define DL_FLAG_RPM_ACTIVE BIT(3)
446 #define DL_FLAG_AUTOREMOVE_SUPPLIER BIT(4)
447 #define DL_FLAG_AUTOPROBE_CONSUMER BIT(5)
448 #define DL_FLAG_MANAGED BIT(6)
449 #define DL_FLAG_SYNC_STATE_ONLY BIT(7)
450 #define DL_FLAG_INFERRED BIT(8)
451 #define DL_FLAG_CYCLE BIT(9)
454 * enum dl_dev_state - Device driver presence tracking information.
455 * @DL_DEV_NO_DRIVER: There is no driver attached to the device.
456 * @DL_DEV_PROBING: A driver is probing.
457 * @DL_DEV_DRIVER_BOUND: The driver has been bound to the device.
458 * @DL_DEV_UNBINDING: The driver is unbinding from the device.
461 DL_DEV_NO_DRIVER = 0,
468 * enum device_removable - Whether the device is removable. The criteria for a
469 * device to be classified as removable is determined by its subsystem or bus.
470 * @DEVICE_REMOVABLE_NOT_SUPPORTED: This attribute is not supported for this
472 * @DEVICE_REMOVABLE_UNKNOWN: Device location is Unknown.
473 * @DEVICE_FIXED: Device is not removable by the user.
474 * @DEVICE_REMOVABLE: Device is removable by the user.
476 enum device_removable {
477 DEVICE_REMOVABLE_NOT_SUPPORTED = 0, /* must be 0 */
478 DEVICE_REMOVABLE_UNKNOWN,
484 * struct dev_links_info - Device data related to device links.
485 * @suppliers: List of links to supplier devices.
486 * @consumers: List of links to consumer devices.
487 * @defer_sync: Hook to global list of devices that have deferred sync_state.
488 * @status: Driver status information.
490 struct dev_links_info {
491 struct list_head suppliers;
492 struct list_head consumers;
493 struct list_head defer_sync;
494 enum dl_dev_state status;
498 * struct dev_msi_info - Device data related to MSI
499 * @domain: The MSI interrupt domain associated to the device
500 * @data: Pointer to MSI device data
502 struct dev_msi_info {
503 #ifdef CONFIG_GENERIC_MSI_IRQ
504 struct irq_domain *domain;
505 struct msi_device_data *data;
510 * enum device_physical_location_panel - Describes which panel surface of the
511 * system's housing the device connection point resides on.
512 * @DEVICE_PANEL_TOP: Device connection point is on the top panel.
513 * @DEVICE_PANEL_BOTTOM: Device connection point is on the bottom panel.
514 * @DEVICE_PANEL_LEFT: Device connection point is on the left panel.
515 * @DEVICE_PANEL_RIGHT: Device connection point is on the right panel.
516 * @DEVICE_PANEL_FRONT: Device connection point is on the front panel.
517 * @DEVICE_PANEL_BACK: Device connection point is on the back panel.
518 * @DEVICE_PANEL_UNKNOWN: The panel with device connection point is unknown.
520 enum device_physical_location_panel {
527 DEVICE_PANEL_UNKNOWN,
531 * enum device_physical_location_vertical_position - Describes vertical
532 * position of the device connection point on the panel surface.
533 * @DEVICE_VERT_POS_UPPER: Device connection point is at upper part of panel.
534 * @DEVICE_VERT_POS_CENTER: Device connection point is at center part of panel.
535 * @DEVICE_VERT_POS_LOWER: Device connection point is at lower part of panel.
537 enum device_physical_location_vertical_position {
538 DEVICE_VERT_POS_UPPER,
539 DEVICE_VERT_POS_CENTER,
540 DEVICE_VERT_POS_LOWER,
544 * enum device_physical_location_horizontal_position - Describes horizontal
545 * position of the device connection point on the panel surface.
546 * @DEVICE_HORI_POS_LEFT: Device connection point is at left part of panel.
547 * @DEVICE_HORI_POS_CENTER: Device connection point is at center part of panel.
548 * @DEVICE_HORI_POS_RIGHT: Device connection point is at right part of panel.
550 enum device_physical_location_horizontal_position {
551 DEVICE_HORI_POS_LEFT,
552 DEVICE_HORI_POS_CENTER,
553 DEVICE_HORI_POS_RIGHT,
557 * struct device_physical_location - Device data related to physical location
558 * of the device connection point.
559 * @panel: Panel surface of the system's housing that the device connection
561 * @vertical_position: Vertical position of the device connection point within
563 * @horizontal_position: Horizontal position of the device connection point
565 * @dock: Set if the device connection point resides in a docking station or
567 * @lid: Set if this device connection point resides on the lid of laptop
570 struct device_physical_location {
571 enum device_physical_location_panel panel;
572 enum device_physical_location_vertical_position vertical_position;
573 enum device_physical_location_horizontal_position horizontal_position;
579 * struct device - The basic device structure
580 * @parent: The device's "parent" device, the device to which it is attached.
581 * In most cases, a parent device is some sort of bus or host
582 * controller. If parent is NULL, the device, is a top-level device,
583 * which is not usually what you want.
584 * @p: Holds the private data of the driver core portions of the device.
585 * See the comment of the struct device_private for detail.
586 * @kobj: A top-level, abstract class from which other classes are derived.
587 * @init_name: Initial name of the device.
588 * @type: The type of device.
589 * This identifies the device type and carries type-specific
591 * @mutex: Mutex to synchronize calls to its driver.
592 * @bus: Type of bus device is on.
593 * @driver: Which driver has allocated this
594 * @platform_data: Platform data specific to the device.
595 * Example: For devices on custom boards, as typical of embedded
596 * and SOC based hardware, Linux often uses platform_data to point
597 * to board-specific structures describing devices and how they
598 * are wired. That can include what ports are available, chip
599 * variants, which GPIO pins act in what additional roles, and so
600 * on. This shrinks the "Board Support Packages" (BSPs) and
601 * minimizes board-specific #ifdefs in drivers.
602 * @driver_data: Private pointer for driver specific info.
603 * @links: Links to suppliers and consumers of this device.
604 * @power: For device power management.
605 * See Documentation/driver-api/pm/devices.rst for details.
606 * @pm_domain: Provide callbacks that are executed during system suspend,
607 * hibernation, system resume and during runtime PM transitions
608 * along with subsystem-level and driver-level callbacks.
609 * @em_pd: device's energy model performance domain
610 * @pins: For device pin management.
611 * See Documentation/driver-api/pin-control.rst for details.
612 * @msi: MSI related data
613 * @numa_node: NUMA node this device is close to.
614 * @dma_ops: DMA mapping operations for this device.
615 * @dma_mask: Dma mask (if dma'ble device).
616 * @coherent_dma_mask: Like dma_mask, but for alloc_coherent mapping as not all
617 * hardware supports 64-bit addresses for consistent allocations
619 * @bus_dma_limit: Limit of an upstream bridge or bus which imposes a smaller
620 * DMA limit than the device itself supports.
621 * @dma_range_map: map for DMA memory ranges relative to that of RAM
622 * @dma_parms: A low level driver may set these to teach IOMMU code about
623 * segment limitations.
624 * @dma_pools: Dma pools (if dma'ble device).
625 * @dma_mem: Internal for coherent mem override.
626 * @cma_area: Contiguous memory area for dma allocations
627 * @dma_io_tlb_mem: Pointer to the swiotlb pool used. Not for driver use.
628 * @archdata: For arch-specific additions.
629 * @of_node: Associated device tree node.
630 * @fwnode: Associated device node supplied by platform firmware.
631 * @devt: For creating the sysfs "dev".
632 * @id: device instance
633 * @devres_lock: Spinlock to protect the resource of the device.
634 * @devres_head: The resources list of the device.
635 * @knode_class: The node used to add the device to the class list.
636 * @class: The class of the device.
637 * @groups: Optional attribute groups.
638 * @release: Callback to free the device after all references have
639 * gone away. This should be set by the allocator of the
640 * device (i.e. the bus driver that discovered the device).
641 * @iommu_group: IOMMU group the device belongs to.
642 * @iommu: Per device generic IOMMU runtime data
643 * @physical_location: Describes physical location of the device connection
644 * point in the system housing.
645 * @removable: Whether the device can be removed from the system. This
646 * should be set by the subsystem / bus driver that discovered
649 * @offline_disabled: If set, the device is permanently online.
650 * @offline: Set after successful invocation of bus type's .offline().
651 * @of_node_reused: Set if the device-tree node is shared with an ancestor
653 * @state_synced: The hardware state of this device has been synced to match
654 * the software state of this device by calling the driver/bus
655 * sync_state() callback.
656 * @can_match: The device has matched with a driver at least once or it is in
657 * a bus (like AMBA) which can't check for matching drivers until
658 * other devices probe successfully.
659 * @dma_coherent: this particular device is dma coherent, even if the
660 * architecture supports non-coherent devices.
661 * @dma_ops_bypass: If set to %true then the dma_ops are bypassed for the
662 * streaming DMA operations (->map_* / ->unmap_* / ->sync_*),
663 * and optionall (if the coherent mask is large enough) also
664 * for dma allocations. This flag is managed by the dma ops
665 * instance from ->dma_supported.
667 * At the lowest level, every device in a Linux system is represented by an
668 * instance of struct device. The device structure contains the information
669 * that the device model core needs to model the system. Most subsystems,
670 * however, track additional information about the devices they host. As a
671 * result, it is rare for devices to be represented by bare device structures;
672 * instead, that structure, like kobject structures, is usually embedded within
673 * a higher-level representation of the device.
677 struct device *parent;
679 struct device_private *p;
681 const char *init_name; /* initial name of the device */
682 const struct device_type *type;
684 const struct bus_type *bus; /* type of bus device is on */
685 struct device_driver *driver; /* which driver has allocated this
687 void *platform_data; /* Platform specific data, device
688 core doesn't touch it */
689 void *driver_data; /* Driver data, set and get with
690 dev_set_drvdata/dev_get_drvdata */
691 struct mutex mutex; /* mutex to synchronize calls to
695 struct dev_links_info links;
696 struct dev_pm_info power;
697 struct dev_pm_domain *pm_domain;
699 #ifdef CONFIG_ENERGY_MODEL
700 struct em_perf_domain *em_pd;
703 #ifdef CONFIG_PINCTRL
704 struct dev_pin_info *pins;
706 struct dev_msi_info msi;
707 #ifdef CONFIG_DMA_OPS
708 const struct dma_map_ops *dma_ops;
710 u64 *dma_mask; /* dma mask (if dma'able device) */
711 u64 coherent_dma_mask;/* Like dma_mask, but for
712 alloc_coherent mappings as
713 not all hardware supports
714 64 bit addresses for consistent
715 allocations such descriptors. */
716 u64 bus_dma_limit; /* upstream dma constraint */
717 const struct bus_dma_region *dma_range_map;
719 struct device_dma_parameters *dma_parms;
721 struct list_head dma_pools; /* dma pools (if dma'ble) */
723 #ifdef CONFIG_DMA_DECLARE_COHERENT
724 struct dma_coherent_mem *dma_mem; /* internal for coherent mem
727 #ifdef CONFIG_DMA_CMA
728 struct cma *cma_area; /* contiguous memory area for dma
731 #ifdef CONFIG_SWIOTLB
732 struct io_tlb_mem *dma_io_tlb_mem;
734 /* arch specific additions */
735 struct dev_archdata archdata;
737 struct device_node *of_node; /* associated device tree node */
738 struct fwnode_handle *fwnode; /* firmware device node */
741 int numa_node; /* NUMA node this device is close to */
743 dev_t devt; /* dev_t, creates the sysfs "dev" */
744 u32 id; /* device instance */
746 spinlock_t devres_lock;
747 struct list_head devres_head;
749 const struct class *class;
750 const struct attribute_group **groups; /* optional groups */
752 void (*release)(struct device *dev);
753 struct iommu_group *iommu_group;
754 struct dev_iommu *iommu;
756 struct device_physical_location *physical_location;
758 enum device_removable removable;
760 bool offline_disabled:1;
762 bool of_node_reused:1;
765 #if defined(CONFIG_ARCH_HAS_SYNC_DMA_FOR_DEVICE) || \
766 defined(CONFIG_ARCH_HAS_SYNC_DMA_FOR_CPU) || \
767 defined(CONFIG_ARCH_HAS_SYNC_DMA_FOR_CPU_ALL)
770 #ifdef CONFIG_DMA_OPS_BYPASS
771 bool dma_ops_bypass : 1;
776 * struct device_link - Device link representation.
777 * @supplier: The device on the supplier end of the link.
778 * @s_node: Hook to the supplier device's list of links to consumers.
779 * @consumer: The device on the consumer end of the link.
780 * @c_node: Hook to the consumer device's list of links to suppliers.
781 * @link_dev: device used to expose link details in sysfs
782 * @status: The state of the link (with respect to the presence of drivers).
783 * @flags: Link flags.
784 * @rpm_active: Whether or not the consumer device is runtime-PM-active.
785 * @kref: Count repeated addition of the same link.
786 * @rm_work: Work structure used for removing the link.
787 * @supplier_preactivated: Supplier has been made active before consumer probe.
790 struct device *supplier;
791 struct list_head s_node;
792 struct device *consumer;
793 struct list_head c_node;
794 struct device link_dev;
795 enum device_link_state status;
797 refcount_t rpm_active;
799 struct work_struct rm_work;
800 bool supplier_preactivated; /* Owned by consumer probe. */
803 #define kobj_to_dev(__kobj) container_of_const(__kobj, struct device, kobj)
806 * device_iommu_mapped - Returns true when the device DMA is translated
808 * @dev: Device to perform the check on
810 static inline bool device_iommu_mapped(struct device *dev)
812 return (dev->iommu_group != NULL);
815 /* Get the wakeup routines, which depend on struct device */
816 #include <linux/pm_wakeup.h>
819 * dev_name - Return a device's name.
820 * @dev: Device with name to get.
821 * Return: The kobject name of the device, or its initial name if unavailable.
823 static inline const char *dev_name(const struct device *dev)
825 /* Use the init name until the kobject becomes available */
827 return dev->init_name;
829 return kobject_name(&dev->kobj);
833 * dev_bus_name - Return a device's bus/class name, if at all possible
834 * @dev: struct device to get the bus/class name of
836 * Will return the name of the bus/class the device is attached to. If it is
837 * not attached to a bus/class, an empty string will be returned.
839 static inline const char *dev_bus_name(const struct device *dev)
841 return dev->bus ? dev->bus->name : (dev->class ? dev->class->name : "");
844 __printf(2, 3) int dev_set_name(struct device *dev, const char *name, ...);
847 static inline int dev_to_node(struct device *dev)
849 return dev->numa_node;
851 static inline void set_dev_node(struct device *dev, int node)
853 dev->numa_node = node;
856 static inline int dev_to_node(struct device *dev)
860 static inline void set_dev_node(struct device *dev, int node)
865 static inline struct irq_domain *dev_get_msi_domain(const struct device *dev)
867 #ifdef CONFIG_GENERIC_MSI_IRQ
868 return dev->msi.domain;
874 static inline void dev_set_msi_domain(struct device *dev, struct irq_domain *d)
876 #ifdef CONFIG_GENERIC_MSI_IRQ
881 static inline void *dev_get_drvdata(const struct device *dev)
883 return dev->driver_data;
886 static inline void dev_set_drvdata(struct device *dev, void *data)
888 dev->driver_data = data;
891 static inline struct pm_subsys_data *dev_to_psd(struct device *dev)
893 return dev ? dev->power.subsys_data : NULL;
896 static inline unsigned int dev_get_uevent_suppress(const struct device *dev)
898 return dev->kobj.uevent_suppress;
901 static inline void dev_set_uevent_suppress(struct device *dev, int val)
903 dev->kobj.uevent_suppress = val;
906 static inline int device_is_registered(struct device *dev)
908 return dev->kobj.state_in_sysfs;
911 static inline void device_enable_async_suspend(struct device *dev)
913 if (!dev->power.is_prepared)
914 dev->power.async_suspend = true;
917 static inline void device_disable_async_suspend(struct device *dev)
919 if (!dev->power.is_prepared)
920 dev->power.async_suspend = false;
923 static inline bool device_async_suspend_enabled(struct device *dev)
925 return !!dev->power.async_suspend;
928 static inline bool device_pm_not_required(struct device *dev)
930 return dev->power.no_pm;
933 static inline void device_set_pm_not_required(struct device *dev)
935 dev->power.no_pm = true;
938 static inline void dev_pm_syscore_device(struct device *dev, bool val)
940 #ifdef CONFIG_PM_SLEEP
941 dev->power.syscore = val;
945 static inline void dev_pm_set_driver_flags(struct device *dev, u32 flags)
947 dev->power.driver_flags = flags;
950 static inline bool dev_pm_test_driver_flags(struct device *dev, u32 flags)
952 return !!(dev->power.driver_flags & flags);
955 static inline void device_lock(struct device *dev)
957 mutex_lock(&dev->mutex);
960 static inline int device_lock_interruptible(struct device *dev)
962 return mutex_lock_interruptible(&dev->mutex);
965 static inline int device_trylock(struct device *dev)
967 return mutex_trylock(&dev->mutex);
970 static inline void device_unlock(struct device *dev)
972 mutex_unlock(&dev->mutex);
975 static inline void device_lock_assert(struct device *dev)
977 lockdep_assert_held(&dev->mutex);
980 static inline struct device_node *dev_of_node(struct device *dev)
982 if (!IS_ENABLED(CONFIG_OF) || !dev)
987 static inline bool dev_has_sync_state(struct device *dev)
991 if (dev->driver && dev->driver->sync_state)
993 if (dev->bus && dev->bus->sync_state)
998 static inline void dev_set_removable(struct device *dev,
999 enum device_removable removable)
1001 dev->removable = removable;
1004 static inline bool dev_is_removable(struct device *dev)
1006 return dev->removable == DEVICE_REMOVABLE;
1009 static inline bool dev_removable_is_valid(struct device *dev)
1011 return dev->removable != DEVICE_REMOVABLE_NOT_SUPPORTED;
1015 * High level routines for use by the bus drivers
1017 int __must_check device_register(struct device *dev);
1018 void device_unregister(struct device *dev);
1019 void device_initialize(struct device *dev);
1020 int __must_check device_add(struct device *dev);
1021 void device_del(struct device *dev);
1022 int device_for_each_child(struct device *dev, void *data,
1023 int (*fn)(struct device *dev, void *data));
1024 int device_for_each_child_reverse(struct device *dev, void *data,
1025 int (*fn)(struct device *dev, void *data));
1026 struct device *device_find_child(struct device *dev, void *data,
1027 int (*match)(struct device *dev, void *data));
1028 struct device *device_find_child_by_name(struct device *parent,
1030 struct device *device_find_any_child(struct device *parent);
1032 int device_rename(struct device *dev, const char *new_name);
1033 int device_move(struct device *dev, struct device *new_parent,
1034 enum dpm_order dpm_order);
1035 int device_change_owner(struct device *dev, kuid_t kuid, kgid_t kgid);
1036 int device_is_dependent(struct device *dev, void *target);
1038 static inline bool device_supports_offline(struct device *dev)
1040 return dev->bus && dev->bus->offline && dev->bus->online;
1043 #define __device_lock_set_class(dev, name, key) \
1045 struct device *__d2 __maybe_unused = dev; \
1046 lock_set_class(&__d2->mutex.dep_map, name, key, 0, _THIS_IP_); \
1050 * device_lock_set_class - Specify a temporary lock class while a device
1051 * is attached to a driver
1052 * @dev: device to modify
1053 * @key: lock class key data
1055 * This must be called with the device_lock() already held, for example
1056 * from driver ->probe(). Take care to only override the default
1057 * lockdep_no_validate class.
1059 #ifdef CONFIG_LOCKDEP
1060 #define device_lock_set_class(dev, key) \
1062 struct device *__d = dev; \
1063 dev_WARN_ONCE(__d, !lockdep_match_class(&__d->mutex, \
1064 &__lockdep_no_validate__), \
1065 "overriding existing custom lock class\n"); \
1066 __device_lock_set_class(__d, #key, key); \
1069 #define device_lock_set_class(dev, key) __device_lock_set_class(dev, #key, key)
1073 * device_lock_reset_class - Return a device to the default lockdep novalidate state
1074 * @dev: device to modify
1076 * This must be called with the device_lock() already held, for example
1077 * from driver ->remove().
1079 #define device_lock_reset_class(dev) \
1081 struct device *__d __maybe_unused = dev; \
1082 lock_set_novalidate_class(&__d->mutex.dep_map, "&dev->mutex", \
1086 void lock_device_hotplug(void);
1087 void unlock_device_hotplug(void);
1088 int lock_device_hotplug_sysfs(void);
1089 int device_offline(struct device *dev);
1090 int device_online(struct device *dev);
1091 void set_primary_fwnode(struct device *dev, struct fwnode_handle *fwnode);
1092 void set_secondary_fwnode(struct device *dev, struct fwnode_handle *fwnode);
1093 void device_set_of_node_from_dev(struct device *dev, const struct device *dev2);
1094 void device_set_node(struct device *dev, struct fwnode_handle *fwnode);
1096 static inline int dev_num_vf(struct device *dev)
1098 if (dev->bus && dev->bus->num_vf)
1099 return dev->bus->num_vf(dev);
1104 * Root device objects for grouping under /sys/devices
1106 struct device *__root_device_register(const char *name, struct module *owner);
1108 /* This is a macro to avoid include problems with THIS_MODULE */
1109 #define root_device_register(name) \
1110 __root_device_register(name, THIS_MODULE)
1112 void root_device_unregister(struct device *root);
1114 static inline void *dev_get_platdata(const struct device *dev)
1116 return dev->platform_data;
1120 * Manual binding of a device to driver. See drivers/base/bus.c
1121 * for information on use.
1123 int __must_check device_driver_attach(struct device_driver *drv,
1124 struct device *dev);
1125 int __must_check device_bind_driver(struct device *dev);
1126 void device_release_driver(struct device *dev);
1127 int __must_check device_attach(struct device *dev);
1128 int __must_check driver_attach(struct device_driver *drv);
1129 void device_initial_probe(struct device *dev);
1130 int __must_check device_reprobe(struct device *dev);
1132 bool device_is_bound(struct device *dev);
1135 * Easy functions for dynamically creating devices on the fly
1137 __printf(5, 6) struct device *
1138 device_create(const struct class *cls, struct device *parent, dev_t devt,
1139 void *drvdata, const char *fmt, ...);
1140 __printf(6, 7) struct device *
1141 device_create_with_groups(const struct class *cls, struct device *parent, dev_t devt,
1142 void *drvdata, const struct attribute_group **groups,
1143 const char *fmt, ...);
1144 void device_destroy(const struct class *cls, dev_t devt);
1146 int __must_check device_add_groups(struct device *dev,
1147 const struct attribute_group **groups);
1148 void device_remove_groups(struct device *dev,
1149 const struct attribute_group **groups);
1151 static inline int __must_check device_add_group(struct device *dev,
1152 const struct attribute_group *grp)
1154 const struct attribute_group *groups[] = { grp, NULL };
1156 return device_add_groups(dev, groups);
1159 static inline void device_remove_group(struct device *dev,
1160 const struct attribute_group *grp)
1162 const struct attribute_group *groups[] = { grp, NULL };
1164 return device_remove_groups(dev, groups);
1167 int __must_check devm_device_add_groups(struct device *dev,
1168 const struct attribute_group **groups);
1169 int __must_check devm_device_add_group(struct device *dev,
1170 const struct attribute_group *grp);
1173 * Platform "fixup" functions - allow the platform to have their say
1174 * about devices and actions that the general device layer doesn't
1177 /* Notify platform of device discovery */
1178 extern int (*platform_notify)(struct device *dev);
1180 extern int (*platform_notify_remove)(struct device *dev);
1184 * get_device - atomically increment the reference count for the device.
1187 struct device *get_device(struct device *dev);
1188 void put_device(struct device *dev);
1189 bool kill_device(struct device *dev);
1191 #ifdef CONFIG_DEVTMPFS
1192 int devtmpfs_mount(void);
1194 static inline int devtmpfs_mount(void) { return 0; }
1197 /* drivers/base/power/shutdown.c */
1198 void device_shutdown(void);
1200 /* debugging and troubleshooting/diagnostic helpers. */
1201 const char *dev_driver_string(const struct device *dev);
1203 /* Device links interface. */
1204 struct device_link *device_link_add(struct device *consumer,
1205 struct device *supplier, u32 flags);
1206 void device_link_del(struct device_link *link);
1207 void device_link_remove(void *consumer, struct device *supplier);
1208 void device_links_supplier_sync_state_pause(void);
1209 void device_links_supplier_sync_state_resume(void);
1211 __printf(3, 4) int dev_err_probe(const struct device *dev, int err, const char *fmt, ...);
1213 /* Create alias, so I can be autoloaded. */
1214 #define MODULE_ALIAS_CHARDEV(major,minor) \
1215 MODULE_ALIAS("char-major-" __stringify(major) "-" __stringify(minor))
1216 #define MODULE_ALIAS_CHARDEV_MAJOR(major) \
1217 MODULE_ALIAS("char-major-" __stringify(major) "-*")
1219 #endif /* _DEVICE_H_ */