// 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. * @p_cb: Callbacks private to the driver core; no one other than the * driver core is allowed to 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; const 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; struct { /* * Called after remove() and after all devres entries have been * processed. This is a Rust only callback. */ void (*post_unbind_rust)(struct device *dev); } p_cb; }; int __must_check driver_register(struct device_driver *drv); void driver_unregister(struct device_driver *drv); struct device_driver *driver_find(const char *name, const struct bus_type *bus); bool __init driver_probe_done(void); 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) int __must_check driver_create_file(const struct device_driver *driver, const struct driver_attribute *attr); void driver_remove_file(const 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); int __must_check driver_for_each_device(struct device_driver *drv, struct device *start, void *data, device_iter_t fn); struct device *driver_find_device(const struct device_driver *drv, struct device *start, const void *data, device_match_t match); /** * 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(const 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(const 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(const 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(const 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(const struct device_driver *drv, const struct acpi_device *adev) { return driver_find_device(drv, NULL, adev, device_match_acpi_dev); } #else static inline struct device * driver_find_device_by_acpi_dev(const struct device_driver *drv, const void *adev) { return NULL; } #endif 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_ */
