ddc —
VESA Display Data Channel V2 devices
The ddc driver provides support for accessing the VESA
  Display Data Channel Version 2 supported by many video displays.
The ddc device appeared in NetBSD
  4.0.
This driver does not provide any mechanism for access from user applications.
  Its only use at this point is to provide a means for framebuffer device
  drivers to query monitor description data (EDID) using a specialized in-kernel
  API. No support for sending control commands to display devices is provided.