We have a popular solution that is using ADV7610/12 as HDMI input, recently facing HDCP 1.x issue with Amazon Fire TV. I tried on our EVAL-ADV7612-7511 board and can easily reproduce the issue by following steps:
1. power-on Fire TV and plugged into the EVAL board input port_A
2. power-on EVAL board and wait it to initialize
3. I can observed DDC activity between FireTV and ADV7612 using a Quantum Data 980 in pass-through mode that after reading back BKSV ok, writing AKSV, An, FireTV will keep reading Ri=0000 and entered a loop of this (Read BKSV, Write AKSV, An, read Ri), now even I unplug FireTV and plug-in an OK source like a BD player that previous worked with EVAL board will also with ends up with same loop. I read back Ri value using AVES software, it is also all zero.
If I plug the Fire TV later after EVAL board is powered up and stable, this problem won't happen
Thanks in advance