When a device is connected to the server host, jsfw will notice it and assign it to one of the client which will in turn create a virtual device based on it.
The code can theoretically support any kind of device (mouse, keyboard, joystick...) but is artificially limited to PS4 controllers (see `hid.c::filter_event`), because the hidraw interface used to set additional device state (led color, flashing, rumble) only works with them. This could be easily edited tho (see `hid.c::apply_controller_state`, `net.h::MessageControllerState`, `net.c::{msg_serialize, msg_deserialize}` and `client.c::JControllerState`). To set the controller state from the client write the json state to the fifo (by default `/tmp/jsfw_fifo`).