1 | // SPDX-License-Identifier: GPL-2.0 |
2 | /* |
3 | * The driver-specific portions of the driver model |
4 | * |
5 | * Copyright (c) 2001-2003 Patrick Mochel <mochel@osdl.org> |
6 | * Copyright (c) 2004-2009 Greg Kroah-Hartman <gregkh@suse.de> |
7 | * Copyright (c) 2008-2009 Novell Inc. |
8 | * Copyright (c) 2012-2019 Greg Kroah-Hartman <gregkh@linuxfoundation.org> |
9 | * Copyright (c) 2012-2019 Linux Foundation |
10 | * |
11 | * See Documentation/driver-api/driver-model/ for more information. |
12 | */ |
13 | |
14 | #ifndef _DEVICE_DRIVER_H_ |
15 | #define _DEVICE_DRIVER_H_ |
16 | |
17 | #include <linux/kobject.h> |
18 | #include <linux/klist.h> |
19 | #include <linux/pm.h> |
20 | #include <linux/device/bus.h> |
21 | #include <linux/module.h> |
22 | |
23 | /** |
24 | * enum probe_type - device driver probe type to try |
25 | * Device drivers may opt in for special handling of their |
26 | * respective probe routines. This tells the core what to |
27 | * expect and prefer. |
28 | * |
29 | * @PROBE_DEFAULT_STRATEGY: Used by drivers that work equally well |
30 | * whether probed synchronously or asynchronously. |
31 | * @PROBE_PREFER_ASYNCHRONOUS: Drivers for "slow" devices which |
32 | * probing order is not essential for booting the system may |
33 | * opt into executing their probes asynchronously. |
34 | * @PROBE_FORCE_SYNCHRONOUS: Use this to annotate drivers that need |
35 | * their probe routines to run synchronously with driver and |
36 | * device registration (with the exception of -EPROBE_DEFER |
37 | * handling - re-probing always ends up being done asynchronously). |
38 | * |
39 | * Note that the end goal is to switch the kernel to use asynchronous |
40 | * probing by default, so annotating drivers with |
41 | * %PROBE_PREFER_ASYNCHRONOUS is a temporary measure that allows us |
42 | * to speed up boot process while we are validating the rest of the |
43 | * drivers. |
44 | */ |
45 | enum probe_type { |
46 | PROBE_DEFAULT_STRATEGY, |
47 | PROBE_PREFER_ASYNCHRONOUS, |
48 | PROBE_FORCE_SYNCHRONOUS, |
49 | }; |
50 | |
51 | /** |
52 | * struct device_driver - The basic device driver structure |
53 | * @name: Name of the device driver. |
54 | * @bus: The bus which the device of this driver belongs to. |
55 | * @owner: The module owner. |
56 | * @mod_name: Used for built-in modules. |
57 | * @suppress_bind_attrs: Disables bind/unbind via sysfs. |
58 | * @probe_type: Type of the probe (synchronous or asynchronous) to use. |
59 | * @of_match_table: The open firmware table. |
60 | * @acpi_match_table: The ACPI match table. |
61 | * @probe: Called to query the existence of a specific device, |
62 | * whether this driver can work with it, and bind the driver |
63 | * to a specific device. |
64 | * @sync_state: Called to sync device state to software state after all the |
65 | * state tracking consumers linked to this device (present at |
66 | * the time of late_initcall) have successfully bound to a |
67 | * driver. If the device has no consumers, this function will |
68 | * be called at late_initcall_sync level. If the device has |
69 | * consumers that are never bound to a driver, this function |
70 | * will never get called until they do. |
71 | * @remove: Called when the device is removed from the system to |
72 | * unbind a device from this driver. |
73 | * @shutdown: Called at shut-down time to quiesce the device. |
74 | * @suspend: Called to put the device to sleep mode. Usually to a |
75 | * low power state. |
76 | * @resume: Called to bring a device from sleep mode. |
77 | * @groups: Default attributes that get created by the driver core |
78 | * automatically. |
79 | * @dev_groups: Additional attributes attached to device instance once |
80 | * it is bound to the driver. |
81 | * @pm: Power management operations of the device which matched |
82 | * this driver. |
83 | * @coredump: Called when sysfs entry is written to. The device driver |
84 | * is expected to call the dev_coredump API resulting in a |
85 | * uevent. |
86 | * @p: Driver core's private data, no one other than the driver |
87 | * core can touch this. |
88 | * |
89 | * The device driver-model tracks all of the drivers known to the system. |
90 | * The main reason for this tracking is to enable the driver core to match |
91 | * up drivers with new devices. Once drivers are known objects within the |
92 | * system, however, a number of other things become possible. Device drivers |
93 | * can export information and configuration variables that are independent |
94 | * of any specific device. |
95 | */ |
96 | struct device_driver { |
97 | const char *name; |
98 | const struct bus_type *bus; |
99 | |
100 | struct module *owner; |
101 | const char *mod_name; /* used for built-in modules */ |
102 | |
103 | bool suppress_bind_attrs; /* disables bind/unbind via sysfs */ |
104 | enum probe_type probe_type; |
105 | |
106 | const struct of_device_id *of_match_table; |
107 | const struct acpi_device_id *acpi_match_table; |
108 | |
109 | int (*probe) (struct device *dev); |
110 | void (*sync_state)(struct device *dev); |
111 | int (*remove) (struct device *dev); |
112 | void (*shutdown) (struct device *dev); |
113 | int (*suspend) (struct device *dev, pm_message_t state); |
114 | int (*resume) (struct device *dev); |
115 | const struct attribute_group **groups; |
116 | const struct attribute_group **dev_groups; |
117 | |
118 | const struct dev_pm_ops *pm; |
119 | void (*coredump) (struct device *dev); |
120 | |
121 | struct driver_private *p; |
122 | }; |
123 | |
124 | |
125 | int __must_check driver_register(struct device_driver *drv); |
126 | void driver_unregister(struct device_driver *drv); |
127 | |
128 | struct device_driver *driver_find(const char *name, const struct bus_type *bus); |
129 | bool __init driver_probe_done(void); |
130 | void wait_for_device_probe(void); |
131 | void __init wait_for_init_devices_probe(void); |
132 | |
133 | /* sysfs interface for exporting driver attributes */ |
134 | |
135 | struct driver_attribute { |
136 | struct attribute attr; |
137 | ssize_t (*show)(struct device_driver *driver, char *buf); |
138 | ssize_t (*store)(struct device_driver *driver, const char *buf, |
139 | size_t count); |
140 | }; |
141 | |
142 | #define DRIVER_ATTR_RW(_name) \ |
143 | struct driver_attribute driver_attr_##_name = __ATTR_RW(_name) |
144 | #define DRIVER_ATTR_RO(_name) \ |
145 | struct driver_attribute driver_attr_##_name = __ATTR_RO(_name) |
146 | #define DRIVER_ATTR_WO(_name) \ |
147 | struct driver_attribute driver_attr_##_name = __ATTR_WO(_name) |
148 | |
149 | int __must_check driver_create_file(struct device_driver *driver, |
150 | const struct driver_attribute *attr); |
151 | void driver_remove_file(struct device_driver *driver, |
152 | const struct driver_attribute *attr); |
153 | |
154 | int driver_set_override(struct device *dev, const char **override, |
155 | const char *s, size_t len); |
156 | int __must_check driver_for_each_device(struct device_driver *drv, struct device *start, |
157 | void *data, int (*fn)(struct device *dev, void *)); |
158 | struct device *driver_find_device(struct device_driver *drv, |
159 | struct device *start, const void *data, |
160 | int (*match)(struct device *dev, const void *data)); |
161 | |
162 | /** |
163 | * driver_find_device_by_name - device iterator for locating a particular device |
164 | * of a specific name. |
165 | * @drv: the driver we're iterating |
166 | * @name: name of the device to match |
167 | */ |
168 | static inline struct device *driver_find_device_by_name(struct device_driver *drv, |
169 | const char *name) |
170 | { |
171 | return driver_find_device(drv, NULL, data: name, match: device_match_name); |
172 | } |
173 | |
174 | /** |
175 | * driver_find_device_by_of_node- device iterator for locating a particular device |
176 | * by of_node pointer. |
177 | * @drv: the driver we're iterating |
178 | * @np: of_node pointer to match. |
179 | */ |
180 | static inline struct device * |
181 | driver_find_device_by_of_node(struct device_driver *drv, |
182 | const struct device_node *np) |
183 | { |
184 | return driver_find_device(drv, NULL, data: np, match: device_match_of_node); |
185 | } |
186 | |
187 | /** |
188 | * driver_find_device_by_fwnode- device iterator for locating a particular device |
189 | * by fwnode pointer. |
190 | * @drv: the driver we're iterating |
191 | * @fwnode: fwnode pointer to match. |
192 | */ |
193 | static inline struct device * |
194 | driver_find_device_by_fwnode(struct device_driver *drv, |
195 | const struct fwnode_handle *fwnode) |
196 | { |
197 | return driver_find_device(drv, NULL, data: fwnode, match: device_match_fwnode); |
198 | } |
199 | |
200 | /** |
201 | * driver_find_device_by_devt- device iterator for locating a particular device |
202 | * by devt. |
203 | * @drv: the driver we're iterating |
204 | * @devt: devt pointer to match. |
205 | */ |
206 | static inline struct device *driver_find_device_by_devt(struct device_driver *drv, |
207 | dev_t devt) |
208 | { |
209 | return driver_find_device(drv, NULL, data: &devt, match: device_match_devt); |
210 | } |
211 | |
212 | static inline struct device *driver_find_next_device(struct device_driver *drv, |
213 | struct device *start) |
214 | { |
215 | return driver_find_device(drv, start, NULL, match: device_match_any); |
216 | } |
217 | |
218 | #ifdef CONFIG_ACPI |
219 | /** |
220 | * driver_find_device_by_acpi_dev : device iterator for locating a particular |
221 | * device matching the ACPI_COMPANION device. |
222 | * @drv: the driver we're iterating |
223 | * @adev: ACPI_COMPANION device to match. |
224 | */ |
225 | static inline struct device * |
226 | driver_find_device_by_acpi_dev(struct device_driver *drv, |
227 | const struct acpi_device *adev) |
228 | { |
229 | return driver_find_device(drv, NULL, data: adev, match: device_match_acpi_dev); |
230 | } |
231 | #else |
232 | static inline struct device * |
233 | driver_find_device_by_acpi_dev(struct device_driver *drv, const void *adev) |
234 | { |
235 | return NULL; |
236 | } |
237 | #endif |
238 | |
239 | void driver_deferred_probe_add(struct device *dev); |
240 | int driver_deferred_probe_check_state(struct device *dev); |
241 | void driver_init(void); |
242 | |
243 | /** |
244 | * module_driver() - Helper macro for drivers that don't do anything |
245 | * special in module init/exit. This eliminates a lot of boilerplate. |
246 | * Each module may only use this macro once, and calling it replaces |
247 | * module_init() and module_exit(). |
248 | * |
249 | * @__driver: driver name |
250 | * @__register: register function for this driver type |
251 | * @__unregister: unregister function for this driver type |
252 | * @...: Additional arguments to be passed to __register and __unregister. |
253 | * |
254 | * Use this macro to construct bus specific macros for registering |
255 | * drivers, and do not use it on its own. |
256 | */ |
257 | #define module_driver(__driver, __register, __unregister, ...) \ |
258 | static int __init __driver##_init(void) \ |
259 | { \ |
260 | return __register(&(__driver) , ##__VA_ARGS__); \ |
261 | } \ |
262 | module_init(__driver##_init); \ |
263 | static void __exit __driver##_exit(void) \ |
264 | { \ |
265 | __unregister(&(__driver) , ##__VA_ARGS__); \ |
266 | } \ |
267 | module_exit(__driver##_exit); |
268 | |
269 | /** |
270 | * builtin_driver() - Helper macro for drivers that don't do anything |
271 | * special in init and have no exit. This eliminates some boilerplate. |
272 | * Each driver may only use this macro once, and calling it replaces |
273 | * device_initcall (or in some cases, the legacy __initcall). This is |
274 | * meant to be a direct parallel of module_driver() above but without |
275 | * the __exit stuff that is not used for builtin cases. |
276 | * |
277 | * @__driver: driver name |
278 | * @__register: register function for this driver type |
279 | * @...: Additional arguments to be passed to __register |
280 | * |
281 | * Use this macro to construct bus specific macros for registering |
282 | * drivers, and do not use it on its own. |
283 | */ |
284 | #define builtin_driver(__driver, __register, ...) \ |
285 | static int __init __driver##_init(void) \ |
286 | { \ |
287 | return __register(&(__driver) , ##__VA_ARGS__); \ |
288 | } \ |
289 | device_initcall(__driver##_init); |
290 | |
291 | #endif /* _DEVICE_DRIVER_H_ */ |
292 | |