Hi,
We were using Nordic HAL for FEM modules to drive our PA/LNA using nRF52840 on zephyr (no NCS). It was only a basic configuration, where the PA and LNA pins were selected using simple_gpio library present on hal_nordic module with calls to nrf_fem_interface_configuration_get() and nrf_fem_interface_configuration_set() control functions.
With introduction of opensource MPSL on v2.5.0, I couldn't find the control function on the MPSL or anywhere on hal_nordic module, and the old functions were removed. It seems that nrfxlib used by nRF Connect SDK provides a proprietary (compiled) MPSL library. This could explain the "opensource" name on the SL folder on hal_nordic. Links: 1, 2.
Does Nordic pretends to bring back support to FEM control function on zephyr through its MPSL opensource or any other module/library? The hal for FEM on nrf52840 involves a lot of details, e.g. PPI, timers, interrupts, etc and... it was already there before zephyr v2.5.0, working fine.
Thanks!
Best,
There are no plans to provide FEM support in opensource implementation.