Bluetooth HCI UART driver.
This driver is required if you want to use Bluetooth devices with
serial port interface. You will also need this driver if you have
UART based Bluetooth PCMCIA and CF devices like Xircom Credit Card
adapter and BrainBoxes Bluetooth PC Card.

Say Y here to compile support for Bluetooth UART devices into the
kernel or say M to compile it as module (hci_uart).

source code:

drivers/bluetooth/