The HDMI 2.1 TX Subsystem driver is responsible for combining the HDCP 1.4 and HDCP 2.3 driver APIs into a single common API for use by the user level application. The common HDCP driver API is able to handle the following HDCP configurations: HDCP 1.4 only, HDCP 2.3 only, and both. When both protocols are enabled, the common HDCP driver ensures that only one is active at any given time.