summaryrefslogtreecommitdiffstats
path: root/drivers/platform/x86/toshiba_bluetooth.c
blob: 24980076336223147fb179979256be03b6c1e99a (plain)
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
202
203
204
/*
 * Toshiba Bluetooth Enable Driver
 *
 * Copyright (C) 2009 Jes Sorensen <Jes.Sorensen@gmail.com>
 * Copyright (C) 2015 Azael Avalos <coproscefalo@gmail.com>
 *
 * Thanks to Matthew Garrett for background info on ACPI innards which
 * normal people aren't meant to understand :-)
 *
 * This program is free software; you can redistribute it and/or modify
 * it under the terms of the GNU General Public License version 2 as
 * published by the Free Software Foundation.
 *
 * Note the Toshiba Bluetooth RFKill switch seems to be a strange
 * fish. It only provides a BT event when the switch is flipped to
 * the 'on' position. When flipping it to 'off', the USB device is
 * simply pulled away underneath us, without any BT event being
 * delivered.
 */

#define pr_fmt(fmt) KBUILD_MODNAME ": " fmt

#include <linux/kernel.h>
#include <linux/module.h>
#include <linux/init.h>
#include <linux/types.h>
#include <linux/acpi.h>

#define BT_KILLSWITCH_MASK	0x01
#define BT_PLUGGED_MASK		0x40
#define BT_POWER_MASK		0x80

MODULE_AUTHOR("Jes Sorensen <Jes.Sorensen@gmail.com>");
MODULE_DESCRIPTION("Toshiba Laptop ACPI Bluetooth Enable Driver");
MODULE_LICENSE("GPL");

static int toshiba_bt_rfkill_add(struct acpi_device *device);
static int toshiba_bt_rfkill_remove(struct acpi_device *device);
static void toshiba_bt_rfkill_notify(struct acpi_device *device, u32 event);

static const struct acpi_device_id bt_device_ids[] = {
	{ "TOS6205", 0},
	{ "", 0},
};
MODULE_DEVICE_TABLE(acpi, bt_device_ids);

#ifdef CONFIG_PM_SLEEP
static int toshiba_bt_resume(struct device *dev);
#endif
static SIMPLE_DEV_PM_OPS(toshiba_bt_pm, NULL, toshiba_bt_resume);

static struct acpi_driver toshiba_bt_rfkill_driver = {
	.name =		"Toshiba BT",
	.class =	"Toshiba",
	.ids =		bt_device_ids,
	.ops =		{
				.add =		toshiba_bt_rfkill_add,
				.remove =	toshiba_bt_rfkill_remove,
				.notify =	toshiba_bt_rfkill_notify,
			},
	.owner = 	THIS_MODULE,
	.drv.pm =	&toshiba_bt_pm,
};

static int toshiba_bluetooth_present(acpi_handle handle)
{
	acpi_status result;
	u64 bt_present;

	/*
	 * Some Toshiba laptops may have a fake TOS6205 device in
	 * their ACPI BIOS, so query the _STA method to see if there
	 * is really anything there.
	 */
	result = acpi_evaluate_integer(handle, "_STA", NULL, &bt_present);
	if (ACPI_FAILURE(result)) {
		pr_err("ACPI call to query Bluetooth presence failed");
		return -ENXIO;
	} else if (!bt_present) {
		pr_info("Bluetooth device not present\n");
		return -ENODEV;
	}

	return 0;
}

static int toshiba_bluetooth_status(acpi_handle handle)
{
	acpi_status result;
	u64 status;

	result = acpi_evaluate_integer(handle, "BTST", NULL, &status);
	if (ACPI_FAILURE(result)) {
		pr_err("Could not get Bluetooth device status\n");
		return -ENXIO;
	}

	pr_info("Bluetooth status %llu\n", status);

	return status;
}

static int toshiba_bluetooth_enable(acpi_handle handle)
{
	acpi_status result;
	bool killswitch;
	bool powered;
	bool plugged;
	int status;

	/*
	 * Query ACPI to verify RFKill switch is set to 'on'.
	 * If not, we return silently, no need to report it as
	 * an error.
	 */
	status = toshiba_bluetooth_status(handle);
	if (status < 0)
		return status;

	killswitch = (status & BT_KILLSWITCH_MASK) ? true : false;
	powered = (status & BT_POWER_MASK) ? true : false;
	plugged = (status & BT_PLUGGED_MASK) ? true : false;

	if (!killswitch)
		return 0;
	/*
	 * This check ensures to only enable the device if it is powered
	 * off or detached, as some recent devices somehow pass the killswitch
	 * test, causing a loop enabling/disabling the device, see bug 93911.
	 */
	if (powered || plugged)
		return 0;

	result = acpi_evaluate_object(handle, "AUSB", NULL, NULL);
	if (ACPI_FAILURE(result)) {
		pr_err("Could not attach USB Bluetooth device\n");
		return -ENXIO;
	}

	result = acpi_evaluate_object(handle, "BTPO", NULL, NULL);
	if (ACPI_FAILURE(result)) {
		pr_err("Could not power ON Bluetooth device\n");
		return -ENXIO;
	}

	return 0;
}

static int toshiba_bluetooth_disable(acpi_handle handle)
{
	acpi_status result;

	result = acpi_evaluate_object(handle, "BTPF", NULL, NULL);
	if (ACPI_FAILURE(result)) {
		pr_err("Could not power OFF Bluetooth device\n");
		return -ENXIO;
	}

	result = acpi_evaluate_object(handle, "DUSB", NULL, NULL);
	if (ACPI_FAILURE(result)) {
		pr_err("Could not detach USB Bluetooth device\n");
		return -ENXIO;
	}

	return 0;
}

static void toshiba_bt_rfkill_notify(struct acpi_device *device, u32 event)
{
	toshiba_bluetooth_enable(device->handle);
}

#ifdef CONFIG_PM_SLEEP
static int toshiba_bt_resume(struct device *dev)
{
	return toshiba_bluetooth_enable(to_acpi_device(dev)->handle);
}
#endif

static int toshiba_bt_rfkill_add(struct acpi_device *device)
{
	int result;

	result = toshiba_bluetooth_present(device->handle);
	if (result)
		return result;

	pr_info("Toshiba ACPI Bluetooth device driver\n");

	/* Enable the BT device */
	result = toshiba_bluetooth_enable(device->handle);
	if (result)
		return result;

	return result;
}

static int toshiba_bt_rfkill_remove(struct acpi_device *device)
{
	/* clean up */
	return toshiba_bluetooth_disable(device->handle);
}

module_acpi_driver(toshiba_bt_rfkill_driver);