How to select an active daughterboard and antenna on USRP devices in srsRAN?

[HrantH-yan]

I want to use a different (not default) active RF front (daughterboard & antenna) for my application and I'm wondering how to specify it (Using UHD driver)? I thought it is possible to specify it in configuration file, in the "args" that we pass to UHD, but I don't know if it is possible, because in UHD examples this is done differently (calling a special function that does the job, and it doesn't get it's argument from "args").

Here's the link to that example in UHD (quick search to that special function "set_rx_subdev_spec")
https://github.com/EttusResearch/uhd/blob/master/host/examples/rx_ascii_art_dft.cpp#L82

[HrantH-yan]

I've debugged the source code, and found out that in srsRAN_4G/lib/src/phy/rf/rf_uhd_generic.h there is a function in line 53, that calls the uhd function usrp->set_rx_subdev_spec(string), (this is how uhd sets the dboard).

After tracing this function, i found out that in srsRAN_4G/lib/src/phy/rf/rf_uhd_imp.cc in line 604 lies the function that eventually will call
usrp->set_rx_subdev_spec(string) (the function from above). here's how the device is called int rf_uhd_open(char* args, void** h)

But nothing calls rf_uhd_open() in the whole repo, so the daughterboard cannot be selected. Is this a bug? Or maybe there is another way that srsRAN uses to call this function?