Updated from R9.2 to R10.4 on Mx51-BBG system. Used UART2 (ttymxc1) for serial communication to proprietary HW. Tx works fine but absolutely no Rx.
Analysis indicates that ttymxc1 is now owned by gps - where in 9.2 it was bluetooth, not sure this means diddly-squat. mx51_babbage.c file calls correct IOMUX from all I can see.
Not sure if this is a Kernel or Android issue or some service is grabbing the incoming data so my app sees nothing....
Been beating on this for several days and hope that someone out there has encountered a similar issue and could point the way.