// SPDX-License-Identifier: GPL-2.0/* * The driver-specific portions of the driver model * * Copyright (c) 2001-2003 Patrick Mochel <mochel@osdl.org> * Copyright (c) 2004-2009 Greg Kroah-Hartman <gregkh@suse.de> * Copyright (c) 2008-2009 Novell Inc. * Copyright (c) 2012-2019 Greg Kroah-Hartman <gregkh@linuxfoundation.org> * Copyright (c) 2012-2019 Linux Foundation * * See Documentation/driver-api/driver-model/ for more information. */ #ifndef _DEVICE_DRIVER_H_#define _DEVICE_DRIVER_H_ #include <linux/kobject.h>#include <linux/klist.h>#include <linux/pm.h>#include <linux/device/bus.h>#include <linux/module.h> /** * enum probe_type - device driver probe type to try *	Device drivers may opt in for special handling of their *	respective probe routines. This tells the core what to *	expect and prefer. * * @PROBE_DEFAULT_STRATEGY: Used by drivers that work equally well *	whether probed synchronously or asynchronously. * @PROBE_PREFER_ASYNCHRONOUS: Drivers for "slow" devices which *	probing order is not essential for booting the system may *	opt into executing their probes asynchronously. * @PROBE_FORCE_SYNCHRONOUS: Use this to annotate drivers that need *	their probe routines to run synchronously with driver and *	device registration (with the exception of -EPROBE_DEFER *	handling - re-probing always ends up being done asynchronously). * * Note that the end goal is to switch the kernel to use asynchronous * probing by default, so annotating drivers with * %PROBE_PREFER_ASYNCHRONOUS is a temporary measure that allows us * to speed up boot process while we are validating the rest of the * drivers. */enum probe_type {	PROBE_DEFAULT_STRATEGY,	PROBE_PREFER_ASYNCHRONOUS,	PROBE_FORCE_SYNCHRONOUS,}; /** * struct device_driver - The basic device driver structure * @name:	Name of the device driver. * @bus:	The bus which the device of this driver belongs to. * @owner:	The module owner. * @mod_name:	Used for built-in modules. * @suppress_bind_attrs: Disables bind/unbind via sysfs. * @probe_type:	Type of the probe (synchronous or asynchronous) to use. * @of_match_table: The open firmware table. * @acpi_match_table: The ACPI match table. * @probe:	Called to query the existence of a specific device, *		whether this driver can work with it, and bind the driver *		to a specific device. * @sync_state:	Called to sync device state to software state after all the *		state tracking consumers linked to this device (present at *		the time of late_initcall) have successfully bound to a *		driver. If the device has no consumers, this function will *		be called at late_initcall_sync level. If the device has *		consumers that are never bound to a driver, this function *		will never get called until they do. * @remove:	Called when the device is removed from the system to *		unbind a device from this driver. * @shutdown:	Called at shut-down time to quiesce the device. * @suspend:	Called to put the device to sleep mode. Usually to a *		low power state. * @resume:	Called to bring a device from sleep mode. * @groups:	Default attributes that get created by the driver core *		automatically. * @dev_groups:	Additional attributes attached to device instance once *		it is bound to the driver. * @pm:		Power management operations of the device which matched *		this driver. * @coredump:	Called when sysfs entry is written to. The device driver *		is expected to call the dev_coredump API resulting in a *		uevent. * @p:		Driver core's private data, no one other than the driver *		core can touch this. * * The device driver-model tracks all of the drivers known to the system. * The main reason for this tracking is to enable the driver core to match * up drivers with new devices. Once drivers are known objects within the * system, however, a number of other things become possible. Device drivers * can export information and configuration variables that are independent * of any specific device. */struct device_driver {	const char		*name;	struct bus_type		*bus; 	struct module		*owner;	const char		*mod_name;	/* used for built-in modules */ 	bool suppress_bind_attrs;	/* disables bind/unbind via sysfs */	enum probe_type probe_type; 	const struct of_device_id	*of_match_table;	const struct acpi_device_id	*acpi_match_table; 	int (*probe) (struct device *dev);	void (*sync_state)(struct device *dev);	int (*remove) (struct device *dev);	void (*shutdown) (struct device *dev);	int (*suspend) (struct device *dev, pm_message_t state);	int (*resume) (struct device *dev);	const struct attribute_group **groups;	const struct attribute_group **dev_groups; 	const struct dev_pm_ops *pm;	void (*coredump) (struct device *dev); 	struct driver_private *p;};  extern int __must_check driver_register(struct device_driver *drv);extern void driver_unregister(struct device_driver *drv); extern struct device_driver *driver_find(const char *name,					 struct bus_type *bus);extern int driver_probe_done(void);extern void wait_for_device_probe(void);void __init wait_for_init_devices_probe(void); /* sysfs interface for exporting driver attributes */ struct driver_attribute {	struct attribute attr;	ssize_t (*show)(struct device_driver *driver, char *buf);	ssize_t (*store)(struct device_driver *driver, const char *buf,			 size_t count);}; #define DRIVER_ATTR_RW(_name) \	struct driver_attribute driver_attr_##_name = __ATTR_RW(_name)#define DRIVER_ATTR_RO(_name) \	struct driver_attribute driver_attr_##_name = __ATTR_RO(_name)#define DRIVER_ATTR_WO(_name) \	struct driver_attribute driver_attr_##_name = __ATTR_WO(_name) extern int __must_check driver_create_file(struct device_driver *driver,					const struct driver_attribute *attr);extern void driver_remove_file(struct device_driver *driver,			       const struct driver_attribute *attr); int driver_set_override(struct device *dev, const char **override,			const char *s, size_t len);extern int __must_check driver_for_each_device(struct device_driver *drv,					       struct device *start,					       void *data,					       int (*fn)(struct device *dev,							 void *));struct device *driver_find_device(struct device_driver *drv,				  struct device *start, const void *data,				  int (*match)(struct device *dev, const void *data)); /** * driver_find_device_by_name - device iterator for locating a particular device * of a specific name. * @drv: the driver we're iterating * @name: name of the device to match */static inline struct device *driver_find_device_by_name(struct device_driver *drv,							const char *name){	return driver_find_device(drv, NULL, name, device_match_name);} /** * driver_find_device_by_of_node- device iterator for locating a particular device * by of_node pointer. * @drv: the driver we're iterating * @np: of_node pointer to match. */static inline struct device *driver_find_device_by_of_node(struct device_driver *drv,			      const struct device_node *np){	return driver_find_device(drv, NULL, np, device_match_of_node);} /** * driver_find_device_by_fwnode- device iterator for locating a particular device * by fwnode pointer. * @drv: the driver we're iterating * @fwnode: fwnode pointer to match. */static inline struct device *driver_find_device_by_fwnode(struct device_driver *drv,			     const struct fwnode_handle *fwnode){	return driver_find_device(drv, NULL, fwnode, device_match_fwnode);} /** * driver_find_device_by_devt- device iterator for locating a particular device * by devt. * @drv: the driver we're iterating * @devt: devt pointer to match. */static inline struct device *driver_find_device_by_devt(struct device_driver *drv,							dev_t devt){	return driver_find_device(drv, NULL, &devt, device_match_devt);} static inline struct device *driver_find_next_device(struct device_driver *drv,						     struct device *start){	return driver_find_device(drv, start, NULL, device_match_any);} #ifdef CONFIG_ACPI/** * driver_find_device_by_acpi_dev : device iterator for locating a particular * device matching the ACPI_COMPANION device. * @drv: the driver we're iterating * @adev: ACPI_COMPANION device to match. */static inline struct device *driver_find_device_by_acpi_dev(struct device_driver *drv,			       const struct acpi_device *adev){	return driver_find_device(drv, NULL, adev, device_match_acpi_dev);}#elsestatic inline struct device *driver_find_device_by_acpi_dev(struct device_driver *drv, const void *adev){	return NULL;}#endif extern int driver_deferred_probe_timeout;void driver_deferred_probe_add(struct device *dev);int driver_deferred_probe_check_state(struct device *dev);void driver_init(void); /** * module_driver() - Helper macro for drivers that don't do anything * special in module init/exit. This eliminates a lot of boilerplate. * Each module may only use this macro once, and calling it replaces * module_init() and module_exit(). * * @__driver: driver name * @__register: register function for this driver type * @__unregister: unregister function for this driver type * @...: Additional arguments to be passed to __register and __unregister. * * Use this macro to construct bus specific macros for registering * drivers, and do not use it on its own. */#define module_driver(__driver, __register, __unregister, ...) \static int __init __driver##_init(void) \{ \	return __register(&(__driver) , ##__VA_ARGS__); \} \module_init(__driver##_init); \static void __exit __driver##_exit(void) \{ \	__unregister(&(__driver) , ##__VA_ARGS__); \} \module_exit(__driver##_exit); /** * builtin_driver() - Helper macro for drivers that don't do anything * special in init and have no exit. This eliminates some boilerplate. * Each driver may only use this macro once, and calling it replaces * device_initcall (or in some cases, the legacy __initcall).  This is * meant to be a direct parallel of module_driver() above but without * the __exit stuff that is not used for builtin cases. * * @__driver: driver name * @__register: register function for this driver type * @...: Additional arguments to be passed to __register * * Use this macro to construct bus specific macros for registering * drivers, and do not use it on its own. */#define builtin_driver(__driver, __register, ...) \static int __init __driver##_init(void) \{ \	return __register(&(__driver) , ##__VA_ARGS__); \} \device_initcall(__driver##_init); #endif	/* _DEVICE_DRIVER_H_ */