1/*
2 * Toshiba Bluetooth Enable Driver
3 *
4 * Copyright (C) 2009 Jes Sorensen <Jes.Sorensen@gmail.com>
5 *
6 * Thanks to Matthew Garrett for background info on ACPI innards which
7 * normal people aren't meant to understand :-)
8 *
9 * This program is free software; you can redistribute it and/or modify
10 * it under the terms of the GNU General Public License version 2 as
11 * published by the Free Software Foundation.
12 *
13 * Note the Toshiba Bluetooth RFKill switch seems to be a strange
14 * fish. It only provides a BT event when the switch is flipped to
15 * the 'on' position. When flipping it to 'off', the USB device is
16 * simply pulled away underneath us, without any BT event being
17 * delivered.
18 */
19
20#define pr_fmt(fmt) KBUILD_MODNAME ": " fmt
21
22#include <linux/kernel.h>
23#include <linux/module.h>
24#include <linux/init.h>
25#include <linux/types.h>
26#include <acpi/acpi_bus.h>
27#include <acpi/acpi_drivers.h>
28
29MODULE_AUTHOR("Jes Sorensen <Jes.Sorensen@gmail.com>");
30MODULE_DESCRIPTION("Toshiba Laptop ACPI Bluetooth Enable Driver");
31MODULE_LICENSE("GPL");
32
33
34static int toshiba_bt_rfkill_add(struct acpi_device *device);
35static int toshiba_bt_rfkill_remove(struct acpi_device *device, int type);
36static void toshiba_bt_rfkill_notify(struct acpi_device *device, u32 event);
37static int toshiba_bt_resume(struct acpi_device *device);
38
39static const struct acpi_device_id bt_device_ids[] = {
40	{ "TOS6205", 0},
41	{ "", 0},
42};
43MODULE_DEVICE_TABLE(acpi, bt_device_ids);
44
45static struct acpi_driver toshiba_bt_rfkill_driver = {
46	.name =		"Toshiba BT",
47	.class =	"Toshiba",
48	.ids =		bt_device_ids,
49	.ops =		{
50				.add =		toshiba_bt_rfkill_add,
51				.remove =	toshiba_bt_rfkill_remove,
52				.notify =	toshiba_bt_rfkill_notify,
53				.resume =	toshiba_bt_resume,
54			},
55	.owner = 	THIS_MODULE,
56};
57
58
59static int toshiba_bluetooth_enable(acpi_handle handle)
60{
61	acpi_status res1, res2;
62	u64 result;
63
64	/*
65	 * Query ACPI to verify RFKill switch is set to 'on'.
66	 * If not, we return silently, no need to report it as
67	 * an error.
68	 */
69	res1 = acpi_evaluate_integer(handle, "BTST", NULL, &result);
70	if (ACPI_FAILURE(res1))
71		return res1;
72	if (!(result & 0x01))
73		return 0;
74
75	pr_info("Re-enabling Toshiba Bluetooth\n");
76	res1 = acpi_evaluate_object(handle, "AUSB", NULL, NULL);
77	res2 = acpi_evaluate_object(handle, "BTPO", NULL, NULL);
78	if (!ACPI_FAILURE(res1) || !ACPI_FAILURE(res2))
79		return 0;
80
81	pr_warn("Failed to re-enable Toshiba Bluetooth\n");
82
83	return -ENODEV;
84}
85
86static void toshiba_bt_rfkill_notify(struct acpi_device *device, u32 event)
87{
88	toshiba_bluetooth_enable(device->handle);
89}
90
91static int toshiba_bt_resume(struct acpi_device *device)
92{
93	return toshiba_bluetooth_enable(device->handle);
94}
95
96static int toshiba_bt_rfkill_add(struct acpi_device *device)
97{
98	acpi_status status;
99	u64 bt_present;
100	int result = -ENODEV;
101
102	/*
103	 * Some Toshiba laptops may have a fake TOS6205 device in
104	 * their ACPI BIOS, so query the _STA method to see if there
105	 * is really anything there, before trying to enable it.
106	 */
107	status = acpi_evaluate_integer(device->handle, "_STA", NULL,
108				       &bt_present);
109
110	if (!ACPI_FAILURE(status) && bt_present) {
111		pr_info("Detected Toshiba ACPI Bluetooth device - "
112			"installing RFKill handler\n");
113		result = toshiba_bluetooth_enable(device->handle);
114	}
115
116	return result;
117}
118
119static int __init toshiba_bt_rfkill_init(void)
120{
121	int result;
122
123	result = acpi_bus_register_driver(&toshiba_bt_rfkill_driver);
124	if (result < 0) {
125		ACPI_DEBUG_PRINT((ACPI_DB_ERROR,
126				  "Error registering driver\n"));
127		return result;
128	}
129
130	return 0;
131}
132
133static int toshiba_bt_rfkill_remove(struct acpi_device *device, int type)
134{
135	/* clean up */
136	return 0;
137}
138
139static void __exit toshiba_bt_rfkill_exit(void)
140{
141	acpi_bus_unregister_driver(&toshiba_bt_rfkill_driver);
142}
143
144module_init(toshiba_bt_rfkill_init);
145module_exit(toshiba_bt_rfkill_exit);
146