1 /*
2  * toshiba_wmi.c - Toshiba WMI Hotkey Driver
3  *
4  * Copyright (C) 2015 Azael Avalos <coproscefalo@gmail.com>
5  *
6  * This program is free software; you can redistribute it and/or modify
7  * it under the terms of the GNU General Public License as published by
8  * the Free Software Foundation; either version 2 of the License, or
9  * (at your option) any later version.
10  *
11  * This program is distributed in the hope that it will be useful,
12  * but WITHOUT ANY WARRANTY; without even the implied warranty of
13  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
14  * GNU General Public License for more details.
15  *
16  */
17 
18 #define pr_fmt(fmt) KBUILD_MODNAME ": " fmt
19 
20 #include <linux/kernel.h>
21 #include <linux/module.h>
22 #include <linux/init.h>
23 #include <linux/types.h>
24 #include <linux/acpi.h>
25 #include <linux/input.h>
26 #include <linux/input/sparse-keymap.h>
27 #include <linux/dmi.h>
28 
29 MODULE_AUTHOR("Azael Avalos");
30 MODULE_DESCRIPTION("Toshiba WMI Hotkey Driver");
31 MODULE_LICENSE("GPL");
32 
33 #define WMI_EVENT_GUID	"59142400-C6A3-40FA-BADB-8A2652834100"
34 
35 MODULE_ALIAS("wmi:"WMI_EVENT_GUID);
36 
37 static struct input_dev *toshiba_wmi_input_dev;
38 
39 static const struct key_entry toshiba_wmi_keymap[] __initconst = {
40 	/* TODO: Add keymap values once found... */
41 	/*{ KE_KEY, 0x00, { KEY_ } },*/
42 	{ KE_END, 0 }
43 };
44 
45 static void toshiba_wmi_notify(u32 value, void *context)
46 {
47 	struct acpi_buffer response = { ACPI_ALLOCATE_BUFFER, NULL };
48 	union acpi_object *obj;
49 	acpi_status status;
50 
51 	status = wmi_get_event_data(value, &response);
52 	if (ACPI_FAILURE(status)) {
53 		pr_err("Bad event status 0x%x\n", status);
54 		return;
55 	}
56 
57 	obj = (union acpi_object *)response.pointer;
58 	if (!obj)
59 		return;
60 
61 	/* TODO: Add proper checks once we have data */
62 	pr_debug("Unknown event received, obj type %x\n", obj->type);
63 
64 	kfree(response.pointer);
65 }
66 
67 static const struct dmi_system_id toshiba_wmi_dmi_table[] __initconst = {
68 	{
69 		.ident = "Toshiba laptop",
70 		.matches = {
71 			DMI_MATCH(DMI_SYS_VENDOR, "TOSHIBA"),
72 		},
73 	},
74 	{}
75 };
76 
77 static int __init toshiba_wmi_input_setup(void)
78 {
79 	acpi_status status;
80 	int err;
81 
82 	toshiba_wmi_input_dev = input_allocate_device();
83 	if (!toshiba_wmi_input_dev)
84 		return -ENOMEM;
85 
86 	toshiba_wmi_input_dev->name = "Toshiba WMI hotkeys";
87 	toshiba_wmi_input_dev->phys = "wmi/input0";
88 	toshiba_wmi_input_dev->id.bustype = BUS_HOST;
89 
90 	err = sparse_keymap_setup(toshiba_wmi_input_dev,
91 				  toshiba_wmi_keymap, NULL);
92 	if (err)
93 		goto err_free_dev;
94 
95 	status = wmi_install_notify_handler(WMI_EVENT_GUID,
96 					    toshiba_wmi_notify, NULL);
97 	if (ACPI_FAILURE(status)) {
98 		err = -EIO;
99 		goto err_free_dev;
100 	}
101 
102 	err = input_register_device(toshiba_wmi_input_dev);
103 	if (err)
104 		goto err_remove_notifier;
105 
106 	return 0;
107 
108  err_remove_notifier:
109 	wmi_remove_notify_handler(WMI_EVENT_GUID);
110  err_free_dev:
111 	input_free_device(toshiba_wmi_input_dev);
112 	return err;
113 }
114 
115 static void toshiba_wmi_input_destroy(void)
116 {
117 	wmi_remove_notify_handler(WMI_EVENT_GUID);
118 	input_unregister_device(toshiba_wmi_input_dev);
119 }
120 
121 static int __init toshiba_wmi_init(void)
122 {
123 	int ret;
124 
125 	if (!wmi_has_guid(WMI_EVENT_GUID) ||
126 	    !dmi_check_system(toshiba_wmi_dmi_table))
127 		return -ENODEV;
128 
129 	ret = toshiba_wmi_input_setup();
130 	if (ret) {
131 		pr_err("Failed to setup input device\n");
132 		return ret;
133 	}
134 
135 	pr_info("Toshiba WMI Hotkey Driver\n");
136 
137 	return 0;
138 }
139 
140 static void __exit toshiba_wmi_exit(void)
141 {
142 	if (wmi_has_guid(WMI_EVENT_GUID))
143 		toshiba_wmi_input_destroy();
144 }
145 
146 module_init(toshiba_wmi_init);
147 module_exit(toshiba_wmi_exit);
148