I occasionally use the following script to add bluetooth keyboards to my systems, it adds it at a system level, rather than a user level, which seems to make things work right from the boot, and my keyboard(s) are usable from the login prompt.
As written, you'll need bash (v4.0+ hopefully) and the bluez package, which supplies the bluez-simple-agent, bluez-test-device, bluez-test-input programs.
Most of the code below is to implement a list to allow you to choose which device, it really just boils down to the last 6 (non-comment) lines, if you know your BT MAC Address, you can replace all the choice stuff with a static assignment.
#!/bin/bash
#
# L Nix <[email protected]>
# setup-bt-kb : allow choosing & pairing a bluetooth keyboard from the console
#
declare -a addrlist
#
while [ 1 ]; do
echo -n "Scanning for Bluetooth devices ... "
readarray -n 10 -O 0 -t addrlist < <(hcitool scan|grep -v "^Scanning"|sed -e "s/^[ \t]//g" -e "s/\t/ /g" | head -n 9)
echo
echo
length=${#addrlist[@]}
a=1
while [ ${a} -le ${length} ]; do
echo "$a) ${addrlist[$a-1]}"
a=$((a + 1))
done
echo
while [ 1 ]; do
if [ ${length} -gt 0 ]; then
echo -n "Choose (1-${length}), or "
fi
echo -n "'R' to rescan: "
read -n 1 REPLY
echo
case ${REPLY} in
Q)
# just quit
exit 0
;;
[0rR])
echo
REPLY=0
break
;;
[123456789])
if [ ${REPLY} -le ${length} ]; then
echo "Got ${REPLY}"
break
fi
;;
*)
;;
esac
done
if [ ${REPLY} -gt 0 ]; then
break
fi
done
#
device=${addrlist[${REPLY}-1]}
#
BTADDR=${device/% *}
BTNAME=${device/#??:??:??:??:??:?? }
#
echo "selecting '${BTNAME}' at ${BTADDR}"
#
echo "Pairing with ${BTNAME} (Generally '0000')"
bluez-simple-agent hci0 ${BTADDR}
#
echo "Setting trust level with ${BTNAME}"
bluez-test-device trusted ${BTADDR} yes
#
echo "Connecting to ${BTNAME}"
bluez-test-input connect ${BTADDR}
#
echo "Completed"