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 <linux/acpi.h>
27 
28 MODULE_AUTHOR("Jes Sorensen <Jes.Sorensen@gmail.com>");
29 MODULE_DESCRIPTION("Toshiba Laptop ACPI Bluetooth Enable Driver");
30 MODULE_LICENSE("GPL");
31 
32 static int toshiba_bt_rfkill_add(struct acpi_device *device);
33 static int toshiba_bt_rfkill_remove(struct acpi_device *device);
34 static void toshiba_bt_rfkill_notify(struct acpi_device *device, u32 event);
35 
36 static const struct acpi_device_id bt_device_ids[] = {
37 	{ "TOS6205", 0},
38 	{ "", 0},
39 };
40 MODULE_DEVICE_TABLE(acpi, bt_device_ids);
41 
42 #ifdef CONFIG_PM_SLEEP
43 static int toshiba_bt_resume(struct device *dev);
44 #endif
45 static SIMPLE_DEV_PM_OPS(toshiba_bt_pm, NULL, toshiba_bt_resume);
46 
47 static struct acpi_driver toshiba_bt_rfkill_driver = {
48 	.name =		"Toshiba BT",
49 	.class =	"Toshiba",
50 	.ids =		bt_device_ids,
51 	.ops =		{
52 				.add =		toshiba_bt_rfkill_add,
53 				.remove =	toshiba_bt_rfkill_remove,
54 				.notify =	toshiba_bt_rfkill_notify,
55 			},
56 	.owner = 	THIS_MODULE,
57 	.drv.pm =	&toshiba_bt_pm,
58 };
59 
60 
61 static int toshiba_bluetooth_enable(acpi_handle handle)
62 {
63 	acpi_status res1, res2;
64 	u64 result;
65 
66 	/*
67 	 * Query ACPI to verify RFKill switch is set to 'on'.
68 	 * If not, we return silently, no need to report it as
69 	 * an error.
70 	 */
71 	res1 = acpi_evaluate_integer(handle, "BTST", NULL, &result);
72 	if (ACPI_FAILURE(res1))
73 		return res1;
74 	if (!(result & 0x01))
75 		return 0;
76 
77 	pr_info("Re-enabling Toshiba Bluetooth\n");
78 	res1 = acpi_evaluate_object(handle, "AUSB", NULL, NULL);
79 	res2 = acpi_evaluate_object(handle, "BTPO", NULL, NULL);
80 	if (!ACPI_FAILURE(res1) || !ACPI_FAILURE(res2))
81 		return 0;
82 
83 	pr_warn("Failed to re-enable Toshiba Bluetooth\n");
84 
85 	return -ENODEV;
86 }
87 
88 static void toshiba_bt_rfkill_notify(struct acpi_device *device, u32 event)
89 {
90 	toshiba_bluetooth_enable(device->handle);
91 }
92 
93 #ifdef CONFIG_PM_SLEEP
94 static int toshiba_bt_resume(struct device *dev)
95 {
96 	return toshiba_bluetooth_enable(to_acpi_device(dev)->handle);
97 }
98 #endif
99 
100 static int toshiba_bt_rfkill_add(struct acpi_device *device)
101 {
102 	acpi_status status;
103 	u64 bt_present;
104 	int result = -ENODEV;
105 
106 	/*
107 	 * Some Toshiba laptops may have a fake TOS6205 device in
108 	 * their ACPI BIOS, so query the _STA method to see if there
109 	 * is really anything there, before trying to enable it.
110 	 */
111 	status = acpi_evaluate_integer(device->handle, "_STA", NULL,
112 				       &bt_present);
113 
114 	if (!ACPI_FAILURE(status) && bt_present) {
115 		pr_info("Detected Toshiba ACPI Bluetooth device - "
116 			"installing RFKill handler\n");
117 		result = toshiba_bluetooth_enable(device->handle);
118 	}
119 
120 	return result;
121 }
122 
123 static int toshiba_bt_rfkill_remove(struct acpi_device *device)
124 {
125 	/* clean up */
126 	return 0;
127 }
128 
129 module_acpi_driver(toshiba_bt_rfkill_driver);
130