Which specific USB class driver is being used in ADB?

[srinivasan shanmugam]

Dear Android Team,

 I am trying to understand the Linux USB driver stack that is being used currently for ADB usecase, Could anyone please explain, I wanted to know which specific USB class driver (for ex, whether does it is uses serial driver class?),  is being used for ADB usecase.

 

 I have the below understanding that currently that ADB is using ie., as below (But still I am not sure which specific USB class driver does it uses?) , Could any one,  please let me know ?

 

 USB device controller (Hardware) <-> Platform driver (UDC) <-> Gadget driver <-> Composite gadget/UDB core driver <-> Gadget function driver <-> ADB application.

Many Thanks ina dvance,
Srini