xref: /linux-6.15/include/linux/device.h (revision fbcdaa19)
1 // SPDX-License-Identifier: GPL-2.0
2 /*
3  * device.h - generic, centralized driver model
4  *
5  * Copyright (c) 2001-2003 Patrick Mochel <[email protected]>
6  * Copyright (c) 2004-2009 Greg Kroah-Hartman <[email protected]>
7  * Copyright (c) 2008-2009 Novell Inc.
8  *
9  * See Documentation/driver-api/driver-model/ for more information.
10  */
11 
12 #ifndef _DEVICE_H_
13 #define _DEVICE_H_
14 
15 #include <linux/dev_printk.h>
16 #include <linux/energy_model.h>
17 #include <linux/ioport.h>
18 #include <linux/kobject.h>
19 #include <linux/klist.h>
20 #include <linux/list.h>
21 #include <linux/lockdep.h>
22 #include <linux/compiler.h>
23 #include <linux/types.h>
24 #include <linux/mutex.h>
25 #include <linux/pm.h>
26 #include <linux/atomic.h>
27 #include <linux/uidgid.h>
28 #include <linux/gfp.h>
29 #include <linux/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 
35 struct device;
36 struct device_private;
37 struct device_driver;
38 struct driver_private;
39 struct module;
40 struct class;
41 struct subsys_private;
42 struct device_node;
43 struct fwnode_handle;
44 struct iommu_ops;
45 struct iommu_group;
46 struct dev_pin_info;
47 struct dev_iommu;
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  */
62 struct 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 
70 int subsys_interface_register(struct subsys_interface *sif);
71 void subsys_interface_unregister(struct subsys_interface *sif);
72 
73 int subsys_system_register(struct bus_type *subsys,
74 			   const struct attribute_group **groups);
75 int 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  */
87 struct 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 */
99 struct 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 
107 struct dev_ext_attribute {
108 	struct device_attribute attr;
109 	void *var;
110 };
111 
112 ssize_t device_show_ulong(struct device *dev, struct device_attribute *attr,
113 			  char *buf);
114 ssize_t device_store_ulong(struct device *dev, struct device_attribute *attr,
115 			   const char *buf, size_t count);
116 ssize_t device_show_int(struct device *dev, struct device_attribute *attr,
117 			char *buf);
118 ssize_t device_store_int(struct device *dev, struct device_attribute *attr,
119 			 const char *buf, size_t count);
120 ssize_t device_show_bool(struct device *dev, struct device_attribute *attr,
121 			char *buf);
122 ssize_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 
153 int device_create_file(struct device *device,
154 		       const struct device_attribute *entry);
155 void device_remove_file(struct device *dev,
156 			const struct device_attribute *attr);
157 bool device_remove_file_self(struct device *dev,
158 			     const struct device_attribute *attr);
159 int __must_check device_create_bin_file(struct device *dev,
160 					const struct bin_attribute *attr);
161 void device_remove_bin_file(struct device *dev,
162 			    const struct bin_attribute *attr);
163 
164 /* device resource management */
165 typedef void (*dr_release_t)(struct device *dev, void *res);
166 typedef int (*dr_match_t)(struct device *dev, void *res, void *match_data);
167 
168 #ifdef CONFIG_DEBUG_DEVRES
169 void *__devres_alloc_node(dr_release_t release, size_t size, gfp_t gfp,
170 			  int nid, const char *name) __malloc;
171 #define devres_alloc(release, size, gfp) \
172 	__devres_alloc_node(release, size, gfp, NUMA_NO_NODE, #release)
173 #define devres_alloc_node(release, size, gfp, nid) \
174 	__devres_alloc_node(release, size, gfp, nid, #release)
175 #else
176 void *devres_alloc_node(dr_release_t release, size_t size,
177 			gfp_t gfp, int nid) __malloc;
178 static inline void *devres_alloc(dr_release_t release, size_t size, gfp_t gfp)
179 {
180 	return devres_alloc_node(release, size, gfp, NUMA_NO_NODE);
181 }
182 #endif
183 
184 void devres_for_each_res(struct device *dev, dr_release_t release,
185 			 dr_match_t match, void *match_data,
186 			 void (*fn)(struct device *, void *, void *),
187 			 void *data);
188 void devres_free(void *res);
189 void devres_add(struct device *dev, void *res);
190 void *devres_find(struct device *dev, dr_release_t release,
191 		  dr_match_t match, void *match_data);
192 void *devres_get(struct device *dev, void *new_res,
193 		 dr_match_t match, void *match_data);
194 void *devres_remove(struct device *dev, dr_release_t release,
195 		    dr_match_t match, void *match_data);
196 int devres_destroy(struct device *dev, dr_release_t release,
197 		   dr_match_t match, void *match_data);
198 int devres_release(struct device *dev, dr_release_t release,
199 		   dr_match_t match, void *match_data);
200 
201 /* devres group */
202 void * __must_check devres_open_group(struct device *dev, void *id, gfp_t gfp);
203 void devres_close_group(struct device *dev, void *id);
204 void devres_remove_group(struct device *dev, void *id);
205 int devres_release_group(struct device *dev, void *id);
206 
207 /* managed devm_k.alloc/kfree for device drivers */
208 void *devm_kmalloc(struct device *dev, size_t size, gfp_t gfp) __malloc;
209 void *devm_krealloc(struct device *dev, void *ptr, size_t size,
210 		    gfp_t gfp) __must_check;
211 __printf(3, 0) char *devm_kvasprintf(struct device *dev, gfp_t gfp,
212 				     const char *fmt, va_list ap) __malloc;
213 __printf(3, 4) char *devm_kasprintf(struct device *dev, gfp_t gfp,
214 				    const char *fmt, ...) __malloc;
215 static inline void *devm_kzalloc(struct device *dev, size_t size, gfp_t gfp)
216 {
217 	return devm_kmalloc(dev, size, gfp | __GFP_ZERO);
218 }
219 static inline void *devm_kmalloc_array(struct device *dev,
220 				       size_t n, size_t size, gfp_t flags)
221 {
222 	size_t bytes;
223 
224 	if (unlikely(check_mul_overflow(n, size, &bytes)))
225 		return NULL;
226 
227 	return devm_kmalloc(dev, bytes, flags);
228 }
229 static inline void *devm_kcalloc(struct device *dev,
230 				 size_t n, size_t size, gfp_t flags)
231 {
232 	return devm_kmalloc_array(dev, n, size, flags | __GFP_ZERO);
233 }
234 void devm_kfree(struct device *dev, const void *p);
235 char *devm_kstrdup(struct device *dev, const char *s, gfp_t gfp) __malloc;
236 const char *devm_kstrdup_const(struct device *dev, const char *s, gfp_t gfp);
237 void *devm_kmemdup(struct device *dev, const void *src, size_t len, gfp_t gfp);
238 
239 unsigned long devm_get_free_pages(struct device *dev,
240 				  gfp_t gfp_mask, unsigned int order);
241 void devm_free_pages(struct device *dev, unsigned long addr);
242 
243 void __iomem *devm_ioremap_resource(struct device *dev,
244 				    const struct resource *res);
245 void __iomem *devm_ioremap_resource_wc(struct device *dev,
246 				       const struct resource *res);
247 
248 void __iomem *devm_of_iomap(struct device *dev,
249 			    struct device_node *node, int index,
250 			    resource_size_t *size);
251 
252 /* allows to add/remove a custom action to devres stack */
253 int devm_add_action(struct device *dev, void (*action)(void *), void *data);
254 void devm_remove_action(struct device *dev, void (*action)(void *), void *data);
255 void devm_release_action(struct device *dev, void (*action)(void *), void *data);
256 
257 static inline int devm_add_action_or_reset(struct device *dev,
258 					   void (*action)(void *), void *data)
259 {
260 	int ret;
261 
262 	ret = devm_add_action(dev, action, data);
263 	if (ret)
264 		action(data);
265 
266 	return ret;
267 }
268 
269 /**
270  * devm_alloc_percpu - Resource-managed alloc_percpu
271  * @dev: Device to allocate per-cpu memory for
272  * @type: Type to allocate per-cpu memory for
273  *
274  * Managed alloc_percpu. Per-cpu memory allocated with this function is
275  * automatically freed on driver detach.
276  *
277  * RETURNS:
278  * Pointer to allocated memory on success, NULL on failure.
279  */
280 #define devm_alloc_percpu(dev, type)      \
281 	((typeof(type) __percpu *)__devm_alloc_percpu((dev), sizeof(type), \
282 						      __alignof__(type)))
283 
284 void __percpu *__devm_alloc_percpu(struct device *dev, size_t size,
285 				   size_t align);
286 void devm_free_percpu(struct device *dev, void __percpu *pdata);
287 
288 struct device_dma_parameters {
289 	/*
290 	 * a low level driver may set these to teach IOMMU code about
291 	 * sg limitations.
292 	 */
293 	unsigned int max_segment_size;
294 	unsigned long segment_boundary_mask;
295 };
296 
297 /**
298  * enum device_link_state - Device link states.
299  * @DL_STATE_NONE: The presence of the drivers is not being tracked.
300  * @DL_STATE_DORMANT: None of the supplier/consumer drivers is present.
301  * @DL_STATE_AVAILABLE: The supplier driver is present, but the consumer is not.
302  * @DL_STATE_CONSUMER_PROBE: The consumer is probing (supplier driver present).
303  * @DL_STATE_ACTIVE: Both the supplier and consumer drivers are present.
304  * @DL_STATE_SUPPLIER_UNBIND: The supplier driver is unbinding.
305  */
306 enum device_link_state {
307 	DL_STATE_NONE = -1,
308 	DL_STATE_DORMANT = 0,
309 	DL_STATE_AVAILABLE,
310 	DL_STATE_CONSUMER_PROBE,
311 	DL_STATE_ACTIVE,
312 	DL_STATE_SUPPLIER_UNBIND,
313 };
314 
315 /*
316  * Device link flags.
317  *
318  * STATELESS: The core will not remove this link automatically.
319  * AUTOREMOVE_CONSUMER: Remove the link automatically on consumer driver unbind.
320  * PM_RUNTIME: If set, the runtime PM framework will use this link.
321  * RPM_ACTIVE: Run pm_runtime_get_sync() on the supplier during link creation.
322  * AUTOREMOVE_SUPPLIER: Remove the link automatically on supplier driver unbind.
323  * AUTOPROBE_CONSUMER: Probe consumer driver automatically after supplier binds.
324  * MANAGED: The core tracks presence of supplier/consumer drivers (internal).
325  * SYNC_STATE_ONLY: Link only affects sync_state() behavior.
326  */
327 #define DL_FLAG_STATELESS		BIT(0)
328 #define DL_FLAG_AUTOREMOVE_CONSUMER	BIT(1)
329 #define DL_FLAG_PM_RUNTIME		BIT(2)
330 #define DL_FLAG_RPM_ACTIVE		BIT(3)
331 #define DL_FLAG_AUTOREMOVE_SUPPLIER	BIT(4)
332 #define DL_FLAG_AUTOPROBE_CONSUMER	BIT(5)
333 #define DL_FLAG_MANAGED			BIT(6)
334 #define DL_FLAG_SYNC_STATE_ONLY		BIT(7)
335 
336 /**
337  * enum dl_dev_state - Device driver presence tracking information.
338  * @DL_DEV_NO_DRIVER: There is no driver attached to the device.
339  * @DL_DEV_PROBING: A driver is probing.
340  * @DL_DEV_DRIVER_BOUND: The driver has been bound to the device.
341  * @DL_DEV_UNBINDING: The driver is unbinding from the device.
342  */
343 enum dl_dev_state {
344 	DL_DEV_NO_DRIVER = 0,
345 	DL_DEV_PROBING,
346 	DL_DEV_DRIVER_BOUND,
347 	DL_DEV_UNBINDING,
348 };
349 
350 /**
351  * struct dev_links_info - Device data related to device links.
352  * @suppliers: List of links to supplier devices.
353  * @consumers: List of links to consumer devices.
354  * @defer_sync: Hook to global list of devices that have deferred sync_state.
355  * @status: Driver status information.
356  */
357 struct dev_links_info {
358 	struct list_head suppliers;
359 	struct list_head consumers;
360 	struct list_head defer_sync;
361 	enum dl_dev_state status;
362 };
363 
364 /**
365  * struct device - The basic device structure
366  * @parent:	The device's "parent" device, the device to which it is attached.
367  * 		In most cases, a parent device is some sort of bus or host
368  * 		controller. If parent is NULL, the device, is a top-level device,
369  * 		which is not usually what you want.
370  * @p:		Holds the private data of the driver core portions of the device.
371  * 		See the comment of the struct device_private for detail.
372  * @kobj:	A top-level, abstract class from which other classes are derived.
373  * @init_name:	Initial name of the device.
374  * @type:	The type of device.
375  * 		This identifies the device type and carries type-specific
376  * 		information.
377  * @mutex:	Mutex to synchronize calls to its driver.
378  * @lockdep_mutex: An optional debug lock that a subsystem can use as a
379  * 		peer lock to gain localized lockdep coverage of the device_lock.
380  * @bus:	Type of bus device is on.
381  * @driver:	Which driver has allocated this
382  * @platform_data: Platform data specific to the device.
383  * 		Example: For devices on custom boards, as typical of embedded
384  * 		and SOC based hardware, Linux often uses platform_data to point
385  * 		to board-specific structures describing devices and how they
386  * 		are wired.  That can include what ports are available, chip
387  * 		variants, which GPIO pins act in what additional roles, and so
388  * 		on.  This shrinks the "Board Support Packages" (BSPs) and
389  * 		minimizes board-specific #ifdefs in drivers.
390  * @driver_data: Private pointer for driver specific info.
391  * @links:	Links to suppliers and consumers of this device.
392  * @power:	For device power management.
393  *		See Documentation/driver-api/pm/devices.rst for details.
394  * @pm_domain:	Provide callbacks that are executed during system suspend,
395  * 		hibernation, system resume and during runtime PM transitions
396  * 		along with subsystem-level and driver-level callbacks.
397  * @em_pd:	device's energy model performance domain
398  * @pins:	For device pin management.
399  *		See Documentation/driver-api/pinctl.rst for details.
400  * @msi_list:	Hosts MSI descriptors
401  * @msi_domain: The generic MSI domain this device is using.
402  * @numa_node:	NUMA node this device is close to.
403  * @dma_ops:    DMA mapping operations for this device.
404  * @dma_mask:	Dma mask (if dma'ble device).
405  * @coherent_dma_mask: Like dma_mask, but for alloc_coherent mapping as not all
406  * 		hardware supports 64-bit addresses for consistent allocations
407  * 		such descriptors.
408  * @bus_dma_limit: Limit of an upstream bridge or bus which imposes a smaller
409  *		DMA limit than the device itself supports.
410  * @dma_range_map: map for DMA memory ranges relative to that of RAM
411  * @dma_parms:	A low level driver may set these to teach IOMMU code about
412  * 		segment limitations.
413  * @dma_pools:	Dma pools (if dma'ble device).
414  * @dma_mem:	Internal for coherent mem override.
415  * @cma_area:	Contiguous memory area for dma allocations
416  * @archdata:	For arch-specific additions.
417  * @of_node:	Associated device tree node.
418  * @fwnode:	Associated device node supplied by platform firmware.
419  * @devt:	For creating the sysfs "dev".
420  * @id:		device instance
421  * @devres_lock: Spinlock to protect the resource of the device.
422  * @devres_head: The resources list of the device.
423  * @knode_class: The node used to add the device to the class list.
424  * @class:	The class of the device.
425  * @groups:	Optional attribute groups.
426  * @release:	Callback to free the device after all references have
427  * 		gone away. This should be set by the allocator of the
428  * 		device (i.e. the bus driver that discovered the device).
429  * @iommu_group: IOMMU group the device belongs to.
430  * @iommu:	Per device generic IOMMU runtime data
431  *
432  * @offline_disabled: If set, the device is permanently online.
433  * @offline:	Set after successful invocation of bus type's .offline().
434  * @of_node_reused: Set if the device-tree node is shared with an ancestor
435  *              device.
436  * @state_synced: The hardware state of this device has been synced to match
437  *		  the software state of this device by calling the driver/bus
438  *		  sync_state() callback.
439  * @dma_coherent: this particular device is dma coherent, even if the
440  *		architecture supports non-coherent devices.
441  * @dma_ops_bypass: If set to %true then the dma_ops are bypassed for the
442  *		streaming DMA operations (->map_* / ->unmap_* / ->sync_*),
443  *		and optionall (if the coherent mask is large enough) also
444  *		for dma allocations.  This flag is managed by the dma ops
445  *		instance from ->dma_supported.
446  *
447  * At the lowest level, every device in a Linux system is represented by an
448  * instance of struct device. The device structure contains the information
449  * that the device model core needs to model the system. Most subsystems,
450  * however, track additional information about the devices they host. As a
451  * result, it is rare for devices to be represented by bare device structures;
452  * instead, that structure, like kobject structures, is usually embedded within
453  * a higher-level representation of the device.
454  */
455 struct device {
456 	struct kobject kobj;
457 	struct device		*parent;
458 
459 	struct device_private	*p;
460 
461 	const char		*init_name; /* initial name of the device */
462 	const struct device_type *type;
463 
464 	struct bus_type	*bus;		/* type of bus device is on */
465 	struct device_driver *driver;	/* which driver has allocated this
466 					   device */
467 	void		*platform_data;	/* Platform specific data, device
468 					   core doesn't touch it */
469 	void		*driver_data;	/* Driver data, set and get with
470 					   dev_set_drvdata/dev_get_drvdata */
471 #ifdef CONFIG_PROVE_LOCKING
472 	struct mutex		lockdep_mutex;
473 #endif
474 	struct mutex		mutex;	/* mutex to synchronize calls to
475 					 * its driver.
476 					 */
477 
478 	struct dev_links_info	links;
479 	struct dev_pm_info	power;
480 	struct dev_pm_domain	*pm_domain;
481 
482 #ifdef CONFIG_ENERGY_MODEL
483 	struct em_perf_domain	*em_pd;
484 #endif
485 
486 #ifdef CONFIG_GENERIC_MSI_IRQ_DOMAIN
487 	struct irq_domain	*msi_domain;
488 #endif
489 #ifdef CONFIG_PINCTRL
490 	struct dev_pin_info	*pins;
491 #endif
492 #ifdef CONFIG_GENERIC_MSI_IRQ
493 	struct list_head	msi_list;
494 #endif
495 #ifdef CONFIG_DMA_OPS
496 	const struct dma_map_ops *dma_ops;
497 #endif
498 	u64		*dma_mask;	/* dma mask (if dma'able device) */
499 	u64		coherent_dma_mask;/* Like dma_mask, but for
500 					     alloc_coherent mappings as
501 					     not all hardware supports
502 					     64 bit addresses for consistent
503 					     allocations such descriptors. */
504 	u64		bus_dma_limit;	/* upstream dma constraint */
505 	const struct bus_dma_region *dma_range_map;
506 
507 	struct device_dma_parameters *dma_parms;
508 
509 	struct list_head	dma_pools;	/* dma pools (if dma'ble) */
510 
511 #ifdef CONFIG_DMA_DECLARE_COHERENT
512 	struct dma_coherent_mem	*dma_mem; /* internal for coherent mem
513 					     override */
514 #endif
515 #ifdef CONFIG_DMA_CMA
516 	struct cma *cma_area;		/* contiguous memory area for dma
517 					   allocations */
518 #endif
519 	/* arch specific additions */
520 	struct dev_archdata	archdata;
521 
522 	struct device_node	*of_node; /* associated device tree node */
523 	struct fwnode_handle	*fwnode; /* firmware device node */
524 
525 #ifdef CONFIG_NUMA
526 	int		numa_node;	/* NUMA node this device is close to */
527 #endif
528 	dev_t			devt;	/* dev_t, creates the sysfs "dev" */
529 	u32			id;	/* device instance */
530 
531 	spinlock_t		devres_lock;
532 	struct list_head	devres_head;
533 
534 	struct class		*class;
535 	const struct attribute_group **groups;	/* optional groups */
536 
537 	void	(*release)(struct device *dev);
538 	struct iommu_group	*iommu_group;
539 	struct dev_iommu	*iommu;
540 
541 	bool			offline_disabled:1;
542 	bool			offline:1;
543 	bool			of_node_reused:1;
544 	bool			state_synced:1;
545 #if defined(CONFIG_ARCH_HAS_SYNC_DMA_FOR_DEVICE) || \
546     defined(CONFIG_ARCH_HAS_SYNC_DMA_FOR_CPU) || \
547     defined(CONFIG_ARCH_HAS_SYNC_DMA_FOR_CPU_ALL)
548 	bool			dma_coherent:1;
549 #endif
550 #ifdef CONFIG_DMA_OPS_BYPASS
551 	bool			dma_ops_bypass : 1;
552 #endif
553 };
554 
555 /**
556  * struct device_link - Device link representation.
557  * @supplier: The device on the supplier end of the link.
558  * @s_node: Hook to the supplier device's list of links to consumers.
559  * @consumer: The device on the consumer end of the link.
560  * @c_node: Hook to the consumer device's list of links to suppliers.
561  * @link_dev: device used to expose link details in sysfs
562  * @status: The state of the link (with respect to the presence of drivers).
563  * @flags: Link flags.
564  * @rpm_active: Whether or not the consumer device is runtime-PM-active.
565  * @kref: Count repeated addition of the same link.
566  * @rcu_head: An RCU head to use for deferred execution of SRCU callbacks.
567  * @supplier_preactivated: Supplier has been made active before consumer probe.
568  */
569 struct device_link {
570 	struct device *supplier;
571 	struct list_head s_node;
572 	struct device *consumer;
573 	struct list_head c_node;
574 	struct device link_dev;
575 	enum device_link_state status;
576 	u32 flags;
577 	refcount_t rpm_active;
578 	struct kref kref;
579 #ifdef CONFIG_SRCU
580 	struct rcu_head rcu_head;
581 #endif
582 	bool supplier_preactivated; /* Owned by consumer probe. */
583 };
584 
585 static inline struct device *kobj_to_dev(struct kobject *kobj)
586 {
587 	return container_of(kobj, struct device, kobj);
588 }
589 
590 /**
591  * device_iommu_mapped - Returns true when the device DMA is translated
592  *			 by an IOMMU
593  * @dev: Device to perform the check on
594  */
595 static inline bool device_iommu_mapped(struct device *dev)
596 {
597 	return (dev->iommu_group != NULL);
598 }
599 
600 /* Get the wakeup routines, which depend on struct device */
601 #include <linux/pm_wakeup.h>
602 
603 static inline const char *dev_name(const struct device *dev)
604 {
605 	/* Use the init name until the kobject becomes available */
606 	if (dev->init_name)
607 		return dev->init_name;
608 
609 	return kobject_name(&dev->kobj);
610 }
611 
612 __printf(2, 3) int dev_set_name(struct device *dev, const char *name, ...);
613 
614 #ifdef CONFIG_NUMA
615 static inline int dev_to_node(struct device *dev)
616 {
617 	return dev->numa_node;
618 }
619 static inline void set_dev_node(struct device *dev, int node)
620 {
621 	dev->numa_node = node;
622 }
623 #else
624 static inline int dev_to_node(struct device *dev)
625 {
626 	return NUMA_NO_NODE;
627 }
628 static inline void set_dev_node(struct device *dev, int node)
629 {
630 }
631 #endif
632 
633 static inline struct irq_domain *dev_get_msi_domain(const struct device *dev)
634 {
635 #ifdef CONFIG_GENERIC_MSI_IRQ_DOMAIN
636 	return dev->msi_domain;
637 #else
638 	return NULL;
639 #endif
640 }
641 
642 static inline void dev_set_msi_domain(struct device *dev, struct irq_domain *d)
643 {
644 #ifdef CONFIG_GENERIC_MSI_IRQ_DOMAIN
645 	dev->msi_domain = d;
646 #endif
647 }
648 
649 static inline void *dev_get_drvdata(const struct device *dev)
650 {
651 	return dev->driver_data;
652 }
653 
654 static inline void dev_set_drvdata(struct device *dev, void *data)
655 {
656 	dev->driver_data = data;
657 }
658 
659 static inline struct pm_subsys_data *dev_to_psd(struct device *dev)
660 {
661 	return dev ? dev->power.subsys_data : NULL;
662 }
663 
664 static inline unsigned int dev_get_uevent_suppress(const struct device *dev)
665 {
666 	return dev->kobj.uevent_suppress;
667 }
668 
669 static inline void dev_set_uevent_suppress(struct device *dev, int val)
670 {
671 	dev->kobj.uevent_suppress = val;
672 }
673 
674 static inline int device_is_registered(struct device *dev)
675 {
676 	return dev->kobj.state_in_sysfs;
677 }
678 
679 static inline void device_enable_async_suspend(struct device *dev)
680 {
681 	if (!dev->power.is_prepared)
682 		dev->power.async_suspend = true;
683 }
684 
685 static inline void device_disable_async_suspend(struct device *dev)
686 {
687 	if (!dev->power.is_prepared)
688 		dev->power.async_suspend = false;
689 }
690 
691 static inline bool device_async_suspend_enabled(struct device *dev)
692 {
693 	return !!dev->power.async_suspend;
694 }
695 
696 static inline bool device_pm_not_required(struct device *dev)
697 {
698 	return dev->power.no_pm;
699 }
700 
701 static inline void device_set_pm_not_required(struct device *dev)
702 {
703 	dev->power.no_pm = true;
704 }
705 
706 static inline void dev_pm_syscore_device(struct device *dev, bool val)
707 {
708 #ifdef CONFIG_PM_SLEEP
709 	dev->power.syscore = val;
710 #endif
711 }
712 
713 static inline void dev_pm_set_driver_flags(struct device *dev, u32 flags)
714 {
715 	dev->power.driver_flags = flags;
716 }
717 
718 static inline bool dev_pm_test_driver_flags(struct device *dev, u32 flags)
719 {
720 	return !!(dev->power.driver_flags & flags);
721 }
722 
723 static inline void device_lock(struct device *dev)
724 {
725 	mutex_lock(&dev->mutex);
726 }
727 
728 static inline int device_lock_interruptible(struct device *dev)
729 {
730 	return mutex_lock_interruptible(&dev->mutex);
731 }
732 
733 static inline int device_trylock(struct device *dev)
734 {
735 	return mutex_trylock(&dev->mutex);
736 }
737 
738 static inline void device_unlock(struct device *dev)
739 {
740 	mutex_unlock(&dev->mutex);
741 }
742 
743 static inline void device_lock_assert(struct device *dev)
744 {
745 	lockdep_assert_held(&dev->mutex);
746 }
747 
748 static inline struct device_node *dev_of_node(struct device *dev)
749 {
750 	if (!IS_ENABLED(CONFIG_OF) || !dev)
751 		return NULL;
752 	return dev->of_node;
753 }
754 
755 static inline bool dev_has_sync_state(struct device *dev)
756 {
757 	if (!dev)
758 		return false;
759 	if (dev->driver && dev->driver->sync_state)
760 		return true;
761 	if (dev->bus && dev->bus->sync_state)
762 		return true;
763 	return false;
764 }
765 
766 /*
767  * High level routines for use by the bus drivers
768  */
769 int __must_check device_register(struct device *dev);
770 void device_unregister(struct device *dev);
771 void device_initialize(struct device *dev);
772 int __must_check device_add(struct device *dev);
773 void device_del(struct device *dev);
774 int device_for_each_child(struct device *dev, void *data,
775 			  int (*fn)(struct device *dev, void *data));
776 int device_for_each_child_reverse(struct device *dev, void *data,
777 				  int (*fn)(struct device *dev, void *data));
778 struct device *device_find_child(struct device *dev, void *data,
779 				 int (*match)(struct device *dev, void *data));
780 struct device *device_find_child_by_name(struct device *parent,
781 					 const char *name);
782 int device_rename(struct device *dev, const char *new_name);
783 int device_move(struct device *dev, struct device *new_parent,
784 		enum dpm_order dpm_order);
785 int device_change_owner(struct device *dev, kuid_t kuid, kgid_t kgid);
786 const char *device_get_devnode(struct device *dev, umode_t *mode, kuid_t *uid,
787 			       kgid_t *gid, const char **tmp);
788 int device_is_dependent(struct device *dev, void *target);
789 
790 static inline bool device_supports_offline(struct device *dev)
791 {
792 	return dev->bus && dev->bus->offline && dev->bus->online;
793 }
794 
795 void lock_device_hotplug(void);
796 void unlock_device_hotplug(void);
797 int lock_device_hotplug_sysfs(void);
798 int device_offline(struct device *dev);
799 int device_online(struct device *dev);
800 void set_primary_fwnode(struct device *dev, struct fwnode_handle *fwnode);
801 void set_secondary_fwnode(struct device *dev, struct fwnode_handle *fwnode);
802 void device_set_of_node_from_dev(struct device *dev, const struct device *dev2);
803 
804 static inline int dev_num_vf(struct device *dev)
805 {
806 	if (dev->bus && dev->bus->num_vf)
807 		return dev->bus->num_vf(dev);
808 	return 0;
809 }
810 
811 /*
812  * Root device objects for grouping under /sys/devices
813  */
814 struct device *__root_device_register(const char *name, struct module *owner);
815 
816 /* This is a macro to avoid include problems with THIS_MODULE */
817 #define root_device_register(name) \
818 	__root_device_register(name, THIS_MODULE)
819 
820 void root_device_unregister(struct device *root);
821 
822 static inline void *dev_get_platdata(const struct device *dev)
823 {
824 	return dev->platform_data;
825 }
826 
827 /*
828  * Manual binding of a device to driver. See drivers/base/bus.c
829  * for information on use.
830  */
831 int __must_check device_bind_driver(struct device *dev);
832 void device_release_driver(struct device *dev);
833 int  __must_check device_attach(struct device *dev);
834 int __must_check driver_attach(struct device_driver *drv);
835 void device_initial_probe(struct device *dev);
836 int __must_check device_reprobe(struct device *dev);
837 
838 bool device_is_bound(struct device *dev);
839 
840 /*
841  * Easy functions for dynamically creating devices on the fly
842  */
843 __printf(5, 6) struct device *
844 device_create(struct class *cls, struct device *parent, dev_t devt,
845 	      void *drvdata, const char *fmt, ...);
846 __printf(6, 7) struct device *
847 device_create_with_groups(struct class *cls, struct device *parent, dev_t devt,
848 			  void *drvdata, const struct attribute_group **groups,
849 			  const char *fmt, ...);
850 void device_destroy(struct class *cls, dev_t devt);
851 
852 int __must_check device_add_groups(struct device *dev,
853 				   const struct attribute_group **groups);
854 void device_remove_groups(struct device *dev,
855 			  const struct attribute_group **groups);
856 
857 static inline int __must_check device_add_group(struct device *dev,
858 					const struct attribute_group *grp)
859 {
860 	const struct attribute_group *groups[] = { grp, NULL };
861 
862 	return device_add_groups(dev, groups);
863 }
864 
865 static inline void device_remove_group(struct device *dev,
866 				       const struct attribute_group *grp)
867 {
868 	const struct attribute_group *groups[] = { grp, NULL };
869 
870 	return device_remove_groups(dev, groups);
871 }
872 
873 int __must_check devm_device_add_groups(struct device *dev,
874 					const struct attribute_group **groups);
875 void devm_device_remove_groups(struct device *dev,
876 			       const struct attribute_group **groups);
877 int __must_check devm_device_add_group(struct device *dev,
878 				       const struct attribute_group *grp);
879 void devm_device_remove_group(struct device *dev,
880 			      const struct attribute_group *grp);
881 
882 /*
883  * Platform "fixup" functions - allow the platform to have their say
884  * about devices and actions that the general device layer doesn't
885  * know about.
886  */
887 /* Notify platform of device discovery */
888 extern int (*platform_notify)(struct device *dev);
889 
890 extern int (*platform_notify_remove)(struct device *dev);
891 
892 
893 /*
894  * get_device - atomically increment the reference count for the device.
895  *
896  */
897 struct device *get_device(struct device *dev);
898 void put_device(struct device *dev);
899 bool kill_device(struct device *dev);
900 
901 #ifdef CONFIG_DEVTMPFS
902 int devtmpfs_mount(void);
903 #else
904 static inline int devtmpfs_mount(void) { return 0; }
905 #endif
906 
907 /* drivers/base/power/shutdown.c */
908 void device_shutdown(void);
909 
910 /* debugging and troubleshooting/diagnostic helpers. */
911 const char *dev_driver_string(const struct device *dev);
912 
913 /* Device links interface. */
914 struct device_link *device_link_add(struct device *consumer,
915 				    struct device *supplier, u32 flags);
916 void device_link_del(struct device_link *link);
917 void device_link_remove(void *consumer, struct device *supplier);
918 void device_links_supplier_sync_state_pause(void);
919 void device_links_supplier_sync_state_resume(void);
920 
921 extern __printf(3, 4)
922 int dev_err_probe(const struct device *dev, int err, const char *fmt, ...);
923 
924 /* Create alias, so I can be autoloaded. */
925 #define MODULE_ALIAS_CHARDEV(major,minor) \
926 	MODULE_ALIAS("char-major-" __stringify(major) "-" __stringify(minor))
927 #define MODULE_ALIAS_CHARDEV_MAJOR(major) \
928 	MODULE_ALIAS("char-major-" __stringify(major) "-*")
929 
930 #ifdef CONFIG_SYSFS_DEPRECATED
931 extern long sysfs_deprecated;
932 #else
933 #define sysfs_deprecated 0
934 #endif
935 
936 #endif /* _DEVICE_H_ */
937