ATAng support for reading from register on ATAREQUEST command?

I am trying to develop a program that will allow modifications to the Host Protected Area settings and one of the commands (READ NATIVE MAX ADDRESS) returns the native max address back in the register (LBA high, low, mid).

I have been looking at the smartmontools project for pointers on how to write this code and according to that source, this is not possible yet with ATAng.  There is a comment in their code that another command (ATA_CMD_READ_REG) patch has been submitted to ATAng, but it does not appear to have made it into any of the latest sources.

Can anyone offer any information on this?

Thanks,
-Matt