About this issue : "DM6437 VPFE hang/crash after long run",
this issue is caused by one of the GPIO(pin[40] configured as CCDC mode YI4) unable to get input signal(always get 0),
but after we configure this pin to GPIO output mode than re-configure to CCDC mode, the problem can be solved,
what will cause this kind of problem and how to avoid it, thanks.