how to use Generic Bluetooth Adapter download host controller's firmware

Question

I need to develop USB windows driver for my bluetooth host controller like the following ( has no supported drivers).

Windows Generic Adapter driver
USB 2.0 interface
USB bluetooth controller(HCI be compatible with windows driver)

windows generic adapter driver(with bthusb.sys) should be used, but it has no firmware download function.  
From windows document: "a vendor-provided INF file is not necessary for Windows 7 because any USB device that has a USB\Class_E0&SubClass_01&Prot_01 hardware ID will install as a Generic Bluetooth Adapter in Windows 7."  

how can I add the download firmware function? thank you