I need to be able to disable HDCP on the input side (Rx) of a ADV7623. I need to be able to do this in order to force a source device to output copy free video so it can be sent to a display device downstream of the ADV7623 that does not support HDCP. I have to do this on command from an outside controller that will tell me when to disable or enable HDCP on the input. For this application its OK if all the input ports are effected by this setting, I don't need to be able to enable/disable HDCP on a per port basis (it would be nice to know how to do this if possible).
The source device I am dealing with here is a Laptop computer. When first connected to the input of a ADV7623 it will attempt to authenticate with it. If successful it will stay authenticated regardless of whether it is providing any protected content (like playing a movie) or not. However, if it is connected to a device that it fails to authenticate with (or perhaps it does not find the Rx responding to any of the HDCP register reads via the DDC, not sure exactly how it makes its decision here), it will provide unprotected video and will blank the screen or portions of the screen that might be playing protected content (like a movie).