LXR linux/drivers/platform/x86/toshiba

   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