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/compiler_attributes.h> 12 #include <linux/device.h> 13 #include <linux/acpi.h> 14 #include <linux/mod_devicetable.h> 15 #include <linux/types.h> 16 17 /** 18 * struct wmi_device - WMI device structure 19 * @dev: Device associated with this WMI device 20 * @setable: True for devices implementing the Set Control Method 21 * @driver_override: Driver name to force a match; do not set directly, 22 * because core frees it; use driver_set_override() to 23 * set or clear it. 24 * 25 * This represents WMI devices discovered by the WMI driver core. 26 */ 27 struct wmi_device { 28 struct device dev; 29 bool setable; 30 const char *driver_override; 31 }; 32 33 /** 34 * to_wmi_device() - Helper macro to cast a device to a wmi_device 35 * @device: device struct 36 * 37 * Cast a struct device to a struct wmi_device. 38 */ 39 #define to_wmi_device(device) container_of_const(device, struct wmi_device, dev) 40 41 /** 42 * struct wmi_buffer - WMI data buffer 43 * @length: Buffer length in bytes 44 * @data: Pointer to the buffer content 45 * 46 * This structure is used to exchange data with the WMI driver core. 47 */ 48 struct wmi_buffer { 49 size_t length; 50 void *data; 51 }; 52 53 /** 54 * struct wmi_string - WMI string representation 55 * @length: Size of @chars in bytes 56 * @chars: UTF16-LE characters with optional nul termination and padding 57 * 58 * This structure is used when exchanging string data over the WMI interface. 59 */ 60 struct wmi_string { 61 __le16 length; 62 __le16 chars[]; 63 } __packed; 64 65 ssize_t wmi_string_to_utf8s(const struct wmi_string *str, u8 *dst, size_t length); 66 67 ssize_t wmi_string_from_utf8s(struct wmi_string *str, size_t max_chars, const u8 *src, 68 size_t src_length); 69 70 int wmidev_invoke_method(struct wmi_device *wdev, u8 instance, u32 method_id, 71 const struct wmi_buffer *in, struct wmi_buffer *out); 72 73 int wmidev_query_block(struct wmi_device *wdev, u8 instance, struct wmi_buffer *out); 74 75 int wmidev_set_block(struct wmi_device *wdev, u8 instance, const struct wmi_buffer *in); 76 77 acpi_status wmidev_evaluate_method(struct wmi_device *wdev, u8 instance, u32 method_id, 78 const struct acpi_buffer *in, struct acpi_buffer *out); 79 80 union acpi_object *wmidev_block_query(struct wmi_device *wdev, u8 instance); 81 82 acpi_status wmidev_block_set(struct wmi_device *wdev, u8 instance, const struct acpi_buffer *in); 83 84 u8 wmidev_instance_count(struct wmi_device *wdev); 85 86 /** 87 * struct wmi_driver - WMI driver structure 88 * @driver: Driver model structure 89 * @id_table: List of WMI GUIDs supported by this driver 90 * @no_notify_data: Driver supports WMI events which provide no event data 91 * @no_singleton: Driver can be instantiated multiple times 92 * @probe: Callback for device binding 93 * @remove: Callback for device unbinding 94 * @shutdown: Callback for device shutdown 95 * @notify: Callback for receiving WMI events (deprecated) 96 * @notify_new: Callback for receiving WMI events 97 * 98 * This represents WMI drivers which handle WMI devices. The data inside the buffer 99 * passed to the @notify_new callback is guaranteed to be aligned on a 8-byte boundary. 100 */ 101 struct wmi_driver { 102 struct device_driver driver; 103 const struct wmi_device_id *id_table; 104 bool no_notify_data; 105 bool no_singleton; 106 107 int (*probe)(struct wmi_device *wdev, const void *context); 108 void (*remove)(struct wmi_device *wdev); 109 void (*shutdown)(struct wmi_device *wdev); 110 void (*notify)(struct wmi_device *device, union acpi_object *data); 111 void (*notify_new)(struct wmi_device *device, const struct wmi_buffer *data); 112 }; 113 114 /** 115 * to_wmi_driver() - Helper macro to cast a driver to a wmi_driver 116 * @drv: driver struct 117 * 118 * Cast a struct device_driver to a struct wmi_driver. 119 */ 120 #define to_wmi_driver(drv) container_of_const(drv, struct wmi_driver, driver) 121 122 int __must_check __wmi_driver_register(struct wmi_driver *driver, struct module *owner); 123 124 void wmi_driver_unregister(struct wmi_driver *driver); 125 126 /** 127 * wmi_driver_register() - Helper macro to register a WMI driver 128 * @driver: wmi_driver struct 129 * 130 * Helper macro for registering a WMI driver. It automatically passes 131 * THIS_MODULE to the underlying function. 132 */ 133 #define wmi_driver_register(driver) __wmi_driver_register((driver), THIS_MODULE) 134 135 /** 136 * module_wmi_driver() - Helper macro to register/unregister a WMI driver 137 * @__wmi_driver: wmi_driver struct 138 * 139 * Helper macro for WMI drivers which do not do anything special in module 140 * init/exit. This eliminates a lot of boilerplate. Each module may only 141 * use this macro once, and calling it replaces module_init() and module_exit(). 142 */ 143 #define module_wmi_driver(__wmi_driver) \ 144 module_driver(__wmi_driver, wmi_driver_register, \ 145 wmi_driver_unregister) 146 147 #endif 148