Most allinone PC's and bluetooth keyboard / mouse sets which include a
bluetooth dongle, ship with a so called HID proxying bluetooth HCI.
The HID proxying makes the keyboard / mouse show up as regular USB HID
devices (after connecting using the connect button on the device + keyboard),
which makes them work without requiring any manual configuration.
The bluez-hid2hci package contains the hid2hci utility and udev rules to
automatically switch supported Bluetooth devices into regular HCI mode.
Install this package if you want to use the bluetooth function of the HCI
with other bluetooth devices like for example a mobile phone.
Note that after installing this package you will first need to pair your
bluetooth keyboard and mouse with the bluetooth adapter before you can use
them again. Since you cannot use your bluetooth keyboard and mouse until
they are paired, this will require the use of a regular (wired) USB keyboard