Bluetooth

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Bluetooth is a standard for the short-range wireless interconnection of cellular phones, computers, and other electronic devices. In Linux, the canonical implementation of the Bluetooth protocol stack is BlueZ.

1 Installation

  1. Install the bluez package, providing the Bluetooth protocol stack.
  2. Install the bluez-utils package, providing the bluetoothctl utility.
  3. The generic Bluetooth driver is the btusb Kernel module. Check whether that module is loaded. If it's not, then load the module manually or reboot.
  4. Start/enable bluetooth.service.
Note:
  • By default the bluetooth daemon will only give out bnep0 devices to users that are a member of the lp group. Make sure to add your user to that group if you intend to connect to a bluetooth tether. You can change the group that is required in the file /usr/share/dbus-1/system.d/bluetooth.conf.
  • Some Bluetooth adapters are bundled with a Wi-Fi card. These require that the Wi-Fi card is firstly enabled (typically a keyboard shortcut on a laptop) in order to make the Bluetooth adapter visible to the kernel.
  • Some Bluetooth cards (e.g. Broadcom) conflict with the network adapter. Thus, you need to make sure that your Bluetooth device get connected before the network service boot.


1.1 Front-ends

1.1.1 Console

  • Pairing a device from the shell with the bluetoothctl utility is one of the simplest and most reliable options. This will be installed already from the bluez-utils package.
Tip: To automate bluetoothctl commands in scripts, commands can be piped into bluetoothctl like so:
 echo -e "<command1>\n<command2>\n" | bluetoothctl
 # or
bluetoothctl -- command

1.1.2 Graphical

The following packages allow for a graphical interface to customize Bluetooth.

  • GNOME Bluetooth
    • gnome-bluetooth provides the back-end
    • gnome-shell provides the status monitor applet
    • gnome-control-center provides the configuration front-end GUI that can be accessed by typing Bluetooth on the Activities overview, or with the gnome-control-center bluetooth command.
    • You can also launch the bluetooth-sendto command directly to send files to a remote device.
    • To receive files, open the Bluetooth settings panel; you can only receive whilst the Bluetooth panel is open.
  • KDE bluedevil - If there is no Bluetooth icon visible in Dolphin and in the system tray, enable it in the system tray options or add a widget. You can configure Bluedevil and detect Bluetooth devices by clicking the icon. An interface is also available from the KDE System Settings.
  • blueberry - Linux Mint's fork of GNOME Bluetooth, which works in all desktop environments. Blueberry does not support receiving files through Obex Object Push.
  • blueman - A full featured GTK Bluetooth manager, which works in all desktop environments.
  • obexftp/obextool = A tool for transferring files to/from any OBEX enabled device.


2 Pairing

Note: Before using the bluetooth device, make sure that it is not blocked by rfkill.

This section describes directly configuring bluez5 via the bluetoothctl CLI, which might not be necessary if you are using an alternative front-end tool (such as GNOME Bluetooth).

The exact procedure depends on the devices involved and their input functionality. What follows is a general outline of pairing a device using bluetoothctl.

Start the bluetoothctl interactive command. Input help to get a list of available commands.

  1. (optional) Select a default controller with select MAC_address.
  2. Enter power on to turn the power to the controller on. It is off by default and will turn off again each reboot, see #Auto power-on after boot.
  3. Enter devices to get the MAC Address of the device with which to pair.
  4. Enter device discovery mode with scan on command if device is not yet on the list.
  5. Turn the agent on with agent on or choose a specific agent: if you press tab twice after agent you should see a list of available agents, e.g. DisplayOnly KeyboardDisplay NoInputNoOutput DisplayYesNo KeyboardOnly off on.
  6. Enter pair MAC_address to do the pairing (tab completion works).
  7. If using a device without a PIN, one may need to manually trust the device before it can reconnect successfully. Enter trust MAC_address to do so.
  8. Enter connect MAC_address to establish a connection.

An example session may look this way:

# bluetoothctl
[NEW] Controller 00:10:20:30:40:50 pi [default]
[bluetooth]# agent KeyboardOnly
Agent registered
[bluetooth]# default-agent
Default agent request successful
[bluetooth]# power on
Changing power on succeeded
[CHG] Controller 00:10:20:30:40:50 Powered: yes
[bluetooth]# scan on
Discovery started
[CHG] Controller 00:10:20:30:40:50 Discovering: yes
[NEW] Device 00:12:34:56:78:90 myLino
[CHG] Device 00:12:34:56:78:90 LegacyPairing: yes
[bluetooth]# pair 00:12:34:56:78:90
Attempting to pair with 00:12:34:56:78:90
[CHG] Device 00:12:34:56:78:90 Connected: yes
[CHG] Device 00:12:34:56:78:90 Connected: no
[CHG] Device 00:12:34:56:78:90 Connected: yes
Request PIN code
[agent] Enter PIN code: 1234
[CHG] Device 00:12:34:56:78:90 Paired: yes
Pairing successful
[CHG] Device 00:12:34:56:78:90 Connected: no
[bluetooth]# connect 00:12:34:56:78:90
Attempting to connect to 00:12:34:56:78:90
[CHG] Device 00:12:34:56:78:90 Connected: yes
Connection successful


3 Configuration

3.1 Auto power-on after boot

By default, your Bluetooth adapter will not power on after a reboot. The former method by using hciconfig hci0 up is deprecated. Now you just need to add the line AutoEnable=true in /etc/bluetooth/main.conf at the bottom in the [Policy] section:

/etc/bluetooth/main.conf
[Policy]
AutoEnable=true


4 Audio

In order to be able to use audio equipment like bluetooth headphones or speakers, you need to install the additional pulseaudio-bluetooth package. With a default PulseAudio installation you should immediately be able to stream audio from a bluetooth device to your speakers.

If you have a system-wide PulseAudio setup make sure the user running the daemon (usually pulse) is in the lp group and you load the bluetooth modules in your PulseAudio config:

/etc/pulse/system.pa
...
load-module module-bluetooth-policy
load-module module-bluetooth-discover
...

Please have a look at the Bluetooth audio article for more information about bluetooth audio and bluetooth headsets.


5 Troubleshooting

This article or section is out of date.
Please help improve the wiki by updating the article and correcting mistakes.
Note: The hciconfig command has been deprecated in bluez5. Replace 'hciconfig' below with newer commands.

5.1 gnome-bluetooth

If you see this when trying to enable receiving files in bluetooth-properties:

Bluetooth OBEX start failed: Invalid path
Bluetooth FTP start failed: Invalid path

Then make sure that the XDG user directories exist.

5.2 Bluetooth USB Dongle

If you are using a USB dongle, you should check that your Bluetooth dongle is recognized. You can do that by running journalctl -f when you have plugged in the USB dongle (or inspecting /var/log/messages.log). It should look something like the following (look out for hci):

Feb 20 15:00:24 hostname kernel: [ 2661.349823] usb 4-1: new full-speed USB device number 3 using uhci_hcd
Feb 20 15:00:24 hostname bluetoothd[4568]: HCI dev 0 registered
Feb 20 15:00:24 hostname bluetoothd[4568]: Listening for HCI events on hci0
Feb 20 15:00:25 hostname bluetoothd[4568]: HCI dev 0 up
Feb 20 15:00:25 hostname bluetoothd[4568]: Adapter /org/bluez/4568/hci0 has been enabled

If you only get the first two lines, you may see that it found the device but you need to bring it up. Example:

hciconfig -a hci0
hci0:	Type: USB
	BD Address: 00:00:00:00:00:00 ACL MTU: 0:0 SCO MTU: 0:0
	DOWN
	RX bytes:0 acl:0 sco:0 events:0 errors:0
        TX bytes:0 acl:0 sco:0 commands:0 errors:
# hciconfig hci0 up
hciconfig -a hci0
hci0:	Type: USB
	BD Address: 00:02:72:C4:7C:06 ACL MTU: 377:10 SCO MTU: 64:8
	UP RUNNING
	RX bytes:348 acl:0 sco:0 events:11 errors:0
        TX bytes:38 acl:0 sco:0 commands:11 errors:0

To verify that the device was detected you can use hcitool which is part of the bluez-utils. You can get a list of available devices and their identifiers and their MAC address by issuing:

$ hcitool dev
Devices:
        hci0	00:1B:DC:0F:DB:40

More detailed information about the device can be retrieved by using hciconfig.

$ hciconfig -a hci0
hci0:   Type: USB
        BD Address: 00:1B:DC:0F:DB:40 ACL MTU: 310:10 SCO MTU: 64:8
        UP RUNNING PSCAN ISCAN
        RX bytes:1226 acl:0 sco:0 events:27 errors:0
        TX bytes:351 acl:0 sco:0 commands:26 errors:0
        Features: 0xff 0xff 0x8f 0xfe 0x9b 0xf9 0x00 0x80
        Packet type: DM1 DM3 DM5 DH1 DH3 DH5 HV1 HV2 HV3
        Link policy: RSWITCH HOLD SNIFF PARK
        Link mode: SLAVE ACCEPT
        Name: 'BlueZ (0)'
        Class: 0x000100
        Service Classes: Unspecified
        Device Class: Computer, Uncategorized
        HCI Ver: 2.0 (0x3) HCI Rev: 0xc5c LMP Ver: 2.0 (0x3) LMP Subver: 0xc5c
        Manufacturer: Cambridge Silicon Radio (10)

5.2.1 Audio devices start to skip at short distance from dongle

If other devices share the same USB host, they can interrupt communication with audio devices. Make sure it is the only device attached to its bus. For example:

$ lsusb
Bus 002 Device 002: ID 0a12:0001 Cambridge Silicon Radio, Ltd Bluetooth Dongle (HCI mode)
Bus 002 Device 001: ID 1d6b:0002 Linux Foundation 2.0 root hub
Bus 001 Device 004: ID 048d:1345 Integrated Technology Express, Inc. Multi Cardreader
Bus 001 Device 003: ID 0424:a700 Standard Microsystems Corp. 2 Port Hub
Bus 001 Device 002: ID 8087:0024 Intel Corp. Integrated Rate Matching Hub
Bus 001 Device 001: ID 1d6b:0002 Linux Foundation 2.0 root hub

5.3 Logitech Bluetooth USB Dongle

There are Logitech dongles (ex. Logitech MX5000) that can work in two modes: Embedded and HCI. In embedded mode dongle emulates a USB device so it seems to your PC that you are using a normal USB mouse/keyoard.

If you hold the little red Button on the USB BT mini-receiver it will enable the other mode. Hold the red button on the BT dongle and plug it into the computer, and after 3-5 seconds of holding the button, the Bluetooth icon will appear in the system tray.

Alternatively, you can install the bluez-hid2hci package. When you connect your Logitech dongle it will automatically switch.

5.4 hcitool scan: Device not found

  • On some laptops (e.g. Dell Studio 15, Lenovo Thinkpad X1) you have to switch the Bluetooth mode from HID to HCI. Install the bluez-hid2hci package, then udev should do this automatically. Alternatively, you can run this command to switch to HCI manually:
# /usr/lib/udev/hid2hci
  • If the device will not show up and you have a Windows operating system on your machine, try booting it and enable the bluetooth adapter from windows.
  • Sometimes also this simple command helps:
# hciconfig hci0 up

5.5 rfkill unblock: Do not unblock

If your device still soft blocked and you run connman, try this:

$ connmanctl enable bluetooth

5.6 My computer is not visible

Cannot discover computer from your phone? Enable PSCAN and ISCAN:

# enable PSCAN and ISCAN
$ hciconfig hci0 piscan
# check it worked
$ hciconfig
hci0:   Type: USB
        BD Address: 00:12:34:56:78:9A ACL MTU: 192:8 SCO MTU: 64:8
        UP RUNNING PSCAN ISCAN
        RX bytes:20425 acl:115 sco:0 events:526 errors:0
        TX bytes:5543 acl:84 sco:0 commands:340 errors:0
Note: Check DiscoverableTimeout and PairableTimeout in /etc/bluetooth/main.conf

Try changing device class in /etc/bluetooth/main.conf as following:

# Default device class. Only the major and minor device class bits are
# considered.
#Class = 0x000100 (from default config)
Class = 0x100100

This was the only solution to make my computer visible for my phone.

5.7 Logitech keyboard does not pair

If you do not get the passkey when you try to pair your Logitech keyboard, type the following command:

# hciconfig hci0 sspmode 0

If after pairing, the keyboard still does not connect, check the output of hcidump -at. If the latter indicates repeatedly connections-disconnections like the following message:

   status 0x00 handle 11 reason 0x13
   Reason: Remote User Terminated Connection

then, the only solution for now is to install bluez v4.

5.8 HSP/HFP profiles

Likewise, bluez5 removed support for the HSP/HFP profiles used by older headset devices; so they may not work out of the box. In order to get those working, you would need to install PulseAudio (>= version 6), or another application that implements HSP/HFP itself.

5.9 Foxconn / Hon Hai / Lite-On Broadcom device

Some of these devices require the firmware to be flashed into the device at boot. The firmware is not provided by Parabola.

5.10 Intel combined wifi and bluetooth cards

If you have difficulty connecting a bluetooth headset and maintaining good downlink speed, try disabling bluetooth coexistence by adding the following line to /etc/modprobe.d/iwlwifi.conf:

/etc/modprobe.d/iwlwifi.conf
options iwlwifi bt_coex_active=0

5.11 Device connects, then disconnects after a few moments

If you see messages like the following in journalctl output, and your device fails to connect or disconnects shortly after connecting:

bluetoothd: Unable to get connect data for Headset Voice gateway: getpeername: Transport endpoint is not connected (107)
bluetoothd: connect error: Connection refused (111)

This may be because you have already paired the device with the same bluetooth adapter while using another operating system. Some devices cannot handle multiple pairings associated with the same MAC address (i.e., bluetooth adapter). You can fix this by re-pairing the device. Start by removing the device:

$ bluetoothctl
[bluetooth]# devices
Device XX:XX:XX:XX:XX:XX My Device
[bluetooth]# remove XX:XX:XX:XX:XX:XX

Then restart bluetooth.service, turn on your bluetooth adapter, make your device discoverable, re-scan for devices, and re-pair your device. Depending on your bluetooth manager, you may need to perform a full reboot in order to re-discover the device.

5.12 Device does not connect with an error in journal

If you see a message like the following in journalctl output while trying to connect to a device:

a2dp-source profile connect failed for 9C:64:40:22:E1:3F: Protocol not available

try installing pulseaudio-bluetooth and restarting PulseAudio. This error can manifest even while using only file transfer.

5.13 Device does not show up in scan

Some devices using bluetooth low energy do not appear when scanning with bluetoothctl, for example the Logitech MX Master. The simplest way I have found to connect them is by installing bluez-utils-compat, then start bluetooth.service and run the following commands:

# bluetoothctl
[NEW] Controller (MAC) myhostname [default]
[bluetooth]# power on
[CHG] Controller (MAC) Class: 0x0c010c
Changing power on succeeded
[CHG] Controller (MAC) Powered: yes
[bluetooth]# scan on
Discovery started
[CHG] Controller (MAC) Discovering: yes

In another terminal:

# hcitool lescan

Wait until your device shows up, then Ctrl+C hcitool. bluetoothctl should now see your device and pair normally.

5.14 Interference between Headphones and Mouse

If you experience audio stuttering while using a bluetooth mouse and keyboard simultaneously, you can try the following:

# hciconfig hci0 lm ACCEPT,MASTER
# hciconfig hci0 lp HOLD,SNIFF,PARK