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 
28 MODULE_AUTHOR("Azael Avalos");
29 MODULE_DESCRIPTION("Toshiba WMI Hotkey Driver");
30 MODULE_LICENSE("GPL");
31 
32 #define TOSHIBA_WMI_EVENT_GUID	"59142400-C6A3-40FA-BADB-8A2652834100"
33 
34 MODULE_ALIAS("wmi:"TOSHIBA_WMI_EVENT_GUID);
35 
36 static struct input_dev *toshiba_wmi_input_dev;
37 
38 static const struct key_entry toshiba_wmi_keymap[] __initconst = {
39 	/* TODO: Add keymap values once found... */
40 	/*{ KE_KEY, 0x00, { KEY_ } },*/
41 	{ KE_END, 0 }
42 };
43 
44 static void toshiba_wmi_notify(u32 value, void *context)
45 {
46 	struct acpi_buffer response = { ACPI_ALLOCATE_BUFFER, NULL };
47 	union acpi_object *obj;
48 	acpi_status status;
49 
50 	status = wmi_get_event_data(value, &response);
51 	if (ACPI_FAILURE(status)) {
52 		pr_err("Bad event status 0x%x\n", status);
53 		return;
54 	}
55 
56 	obj = (union acpi_object *)response.pointer;
57 	if (!obj)
58 		return;
59 
60 	/* TODO: Add proper checks once we have data */
61 	pr_debug("Unknown event received, obj type %x\n", obj->type);
62 
63 	kfree(response.pointer);
64 }
65 
66 static int __init toshiba_wmi_input_setup(void)
67 {
68 	acpi_status status;
69 	int err;
70 
71 	toshiba_wmi_input_dev = input_allocate_device();
72 	if (!toshiba_wmi_input_dev)
73 		return -ENOMEM;
74 
75 	toshiba_wmi_input_dev->name = "Toshiba WMI hotkeys";
76 	toshiba_wmi_input_dev->phys = "wmi/input0";
77 	toshiba_wmi_input_dev->id.bustype = BUS_HOST;
78 
79 	err = sparse_keymap_setup(toshiba_wmi_input_dev,
80 				  toshiba_wmi_keymap, NULL);
81 	if (err)
82 		goto err_free_dev;
83 
84 	status = wmi_install_notify_handler(TOSHIBA_WMI_EVENT_GUID,
85 					    toshiba_wmi_notify, NULL);
86 	if (ACPI_FAILURE(status)) {
87 		err = -EIO;
88 		goto err_free_keymap;
89 	}
90 
91 	err = input_register_device(toshiba_wmi_input_dev);
92 	if (err)
93 		goto err_remove_notifier;
94 
95 	return 0;
96 
97  err_remove_notifier:
98 	wmi_remove_notify_handler(TOSHIBA_WMI_EVENT_GUID);
99  err_free_keymap:
100 	sparse_keymap_free(toshiba_wmi_input_dev);
101  err_free_dev:
102 	input_free_device(toshiba_wmi_input_dev);
103 	return err;
104 }
105 
106 static void toshiba_wmi_input_destroy(void)
107 {
108 	wmi_remove_notify_handler(TOSHIBA_WMI_EVENT_GUID);
109 	sparse_keymap_free(toshiba_wmi_input_dev);
110 	input_unregister_device(toshiba_wmi_input_dev);
111 }
112 
113 static int __init toshiba_wmi_init(void)
114 {
115 	int ret;
116 
117 	if (!wmi_has_guid(TOSHIBA_WMI_EVENT_GUID))
118 		return -ENODEV;
119 
120 	ret = toshiba_wmi_input_setup();
121 	if (ret) {
122 		pr_err("Failed to setup input device\n");
123 		return ret;
124 	}
125 
126 	pr_info("Toshiba WMI Hotkey Driver\n");
127 
128 	return 0;
129 }
130 
131 static void __exit toshiba_wmi_exit(void)
132 {
133 	if (wmi_has_guid(TOSHIBA_WMI_EVENT_GUID))
134 		toshiba_wmi_input_destroy();
135 }
136 
137 module_init(toshiba_wmi_init);
138 module_exit(toshiba_wmi_exit);
139