g_audio module : How does it works?

If we enable gadget_only_mode under CONFIG_USB_MUSB_GADGET in our kernel or linux based device. if it will work as a gadget. Gadget means if I connect my device to my system then my device will listed as a gadget or as a sound card. I get confused because if we do enable any driver support in our kernel that module will be loaded when same supported device driver device will be connect. Please help me out we we do enable gadget only module in our kernel then if our device will work as a gadget??