From USB.org:
The USB Billboard Device Class definition describes the methods used to communicate the AUM supported by a Device Container to a host system. This includes string descriptors that can be used to provide support details in a human-readable format.
This specification does not describe the functionality/methodology by which the Device Container shall switch to an AUM. An example of a Device Container that shall support this class is one that supports PCIe over the USB Type-C connector.
So essentially there my be no need for a device driver as it appears in the device manager, this simply is used provide information about functions that are available. Don't fall for the use suspect website that claim to have
From: Silicon Labs:
There are 2 main functions in Type-c. One is power negotiation, 2nd is alternate mode.
The USB Billboard Device Class definition describes the methods used to communicate the Alternate Modes supported by a Device Container to a host system. This includes string descriptors that can be used to provide support details in a human-readable format.
If a device fails to successfully enter an Alternate Mode within tAMETimeout then the device shall minimally expose a USB 2.0 interface (USB Billboard Device Class) that is powered by VBUS for popping-up message window to the user.
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