1 /* SPDX-License-Identifier: GPL-2.0-only */
2 /*
3  * wmi.h - ACPI WMI interface
4  *
5  * Copyright (c) 2015 Andrew Lutomirski
6  */
7 
8 #ifndef _LINUX_WMI_H
9 #define _LINUX_WMI_H
10 
11 #include <linux/device.h>
12 #include <linux/acpi.h>
13 #include <linux/mod_devicetable.h>
14 
15 /**
16  * struct wmi_device - WMI device structure
17  * @dev: Device associated with this WMI device
18  * @setable: True for devices implementing the Set Control Method
19  * @driver_override: Driver name to force a match; do not set directly,
20  *		     because core frees it; use driver_set_override() to
21  *		     set or clear it.
22  *
23  * This represents WMI devices discovered by the WMI driver core.
24  */
25 struct wmi_device {
26 	struct device dev;
27 	bool setable;
28 	const char *driver_override;
29 };
30 
31 /**
32  * to_wmi_device() - Helper macro to cast a device to a wmi_device
33  * @device: device struct
34  *
35  * Cast a struct device to a struct wmi_device.
36  */
37 #define to_wmi_device(device)	container_of_const(device, struct wmi_device, dev)
38 
39 extern acpi_status wmidev_evaluate_method(struct wmi_device *wdev,
40 					  u8 instance, u32 method_id,
41 					  const struct acpi_buffer *in,
42 					  struct acpi_buffer *out);
43 
44 extern union acpi_object *wmidev_block_query(struct wmi_device *wdev,
45 					     u8 instance);
46 
47 acpi_status wmidev_block_set(struct wmi_device *wdev, u8 instance, const struct acpi_buffer *in);
48 
49 u8 wmidev_instance_count(struct wmi_device *wdev);
50 
51 /**
52  * struct wmi_driver - WMI driver structure
53  * @driver: Driver model structure
54  * @id_table: List of WMI GUIDs supported by this driver
55  * @no_notify_data: Driver supports WMI events which provide no event data
56  * @no_singleton: Driver can be instantiated multiple times
57  * @probe: Callback for device binding
58  * @remove: Callback for device unbinding
59  * @shutdown: Callback for device shutdown
60  * @notify: Callback for receiving WMI events
61  *
62  * This represents WMI drivers which handle WMI devices.
63  */
64 struct wmi_driver {
65 	struct device_driver driver;
66 	const struct wmi_device_id *id_table;
67 	bool no_notify_data;
68 	bool no_singleton;
69 
70 	int (*probe)(struct wmi_device *wdev, const void *context);
71 	void (*remove)(struct wmi_device *wdev);
72 	void (*shutdown)(struct wmi_device *wdev);
73 	void (*notify)(struct wmi_device *device, union acpi_object *data);
74 };
75 
76 /**
77  * to_wmi_driver() - Helper macro to cast a driver to a wmi_driver
78  * @drv: driver struct
79  *
80  * Cast a struct device_driver to a struct wmi_driver.
81  */
82 #define to_wmi_driver(drv)	container_of_const(drv, struct wmi_driver, driver)
83 
84 extern int __must_check __wmi_driver_register(struct wmi_driver *driver,
85 					      struct module *owner);
86 extern void wmi_driver_unregister(struct wmi_driver *driver);
87 
88 /**
89  * wmi_driver_register() - Helper macro to register a WMI driver
90  * @driver: wmi_driver struct
91  *
92  * Helper macro for registering a WMI driver. It automatically passes
93  * THIS_MODULE to the underlying function.
94  */
95 #define wmi_driver_register(driver) __wmi_driver_register((driver), THIS_MODULE)
96 
97 /**
98  * module_wmi_driver() - Helper macro to register/unregister a WMI driver
99  * @__wmi_driver: wmi_driver struct
100  *
101  * Helper macro for WMI drivers which do not do anything special in module
102  * init/exit. This eliminates a lot of boilerplate. Each module may only
103  * use this macro once, and calling it replaces module_init() and module_exit().
104  */
105 #define module_wmi_driver(__wmi_driver) \
106 	module_driver(__wmi_driver, wmi_driver_register, \
107 		      wmi_driver_unregister)
108 
109 #endif
110