The HP lt4132 LTEHSPA+ 4G Module is a Mini PCIE Module not recognized by u3g and doesn't expose the virtual serial port it should.
The Device identifier (0x03f0 : HP, 0xa31d : lt4132) is not present in
The usb_modeswitching is working but there doesn't seem to be the recognition from the driver to enable the modem.
usb_modeswitch -v 0x03f0 -p 0xa31d -u 3
This device is a rebranded Huawei ME906s-158 that is itself supported.
So here is the output of the usbconfig :
How-To-Repeat: Just plug the PCIe modem into the machine.
Have a look at existing commits for adding new devices:
Created attachment 197759 [details]
usbdevs ID patch
Created attachment 197760 [details]
u3g support patch
So, it might seem weird that a non standard huawei init method, but from what I could've gathered, this modem and ME909 share this quirk.