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
 28MODULE_AUTHOR("Azael Avalos");
 29MODULE_DESCRIPTION("Toshiba WMI Hotkey Driver");
 30MODULE_LICENSE("GPL");
 31
 32#define TOSHIBA_WMI_EVENT_GUID	"59142400-C6A3-40FA-BADB-8A2652834100"
 33
 34MODULE_ALIAS("wmi:"TOSHIBA_WMI_EVENT_GUID);
 35
 36static struct input_dev *toshiba_wmi_input_dev;
 37
 38static 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
 44static 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
 66static 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
106static 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
113static 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
131static void __exit toshiba_wmi_exit(void)
132{
133	if (wmi_has_guid(TOSHIBA_WMI_EVENT_GUID))
134		toshiba_wmi_input_destroy();
135}
136
137module_init(toshiba_wmi_init);
138module_exit(toshiba_wmi_exit);