drivers/bluetooth/Config.help

CONFIG_BLUEZ_HCIUART
  Bluetooth HCI UART driver.
  This driver is required if you want to use Bluetooth devices with
  serial port interface.

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

CONFIG_BLUEZ_HCIUSB
  Bluetooth HCI USB driver.
  This driver is required if you want to use Bluetooth devices with
  USB interface.

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

CONFIG_BLUEZ_HCIVHCI
  Bluetooth Virtual HCI device driver.
  This driver is required if you want to use HCI Emulation software.

  Say Y here to compile support for virtual HCI devices into the
  kernel or say M to compile it as module (hci_vhci.o).