drivers/platform/x86/toshiba_bluetooth.c

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