Modem Firmware Upgrade - Modem Busy - USB Issues

[biketool]

https://github.com/the-modem-distro/pine...k/releases

It has been suggested that upgrading the firmware on the modem can help Bookworm users get GPS working.
There is no mention in the troubleshooting if I cant even pass the AT commands as it shows the port busy.
I am running a 3/32gb upgrade board PP.

Code:

mobian@mobian:~$ echo -ne "AT+QFASTBOOT\r" > /dev/ttyUSB2
-bash: /dev/ttyUSB2: Device or resource busy

If I recall correctly and from https://github.com/the-modem-distro/pine...issues/135 you need to run this from a root shell, so run 'sudo su' to enter root shell and then it should work.

tried that now too, I am not a master of the functional differences between sudoing and running as su but it has almost never been important to my work

Code:

mobian@mobian:~$ sudo su
[sudo] password for mobian:
root@mobian:/home/mobian# sudo echo -ne "AT+QFASTBOOT\r" > /dev/ttyUSB2
root@mobian:/home/mobian# fastboot flash modem NON-HLOS.ubi && fastboot reboot
< waiting for any device >

I also tried ADB as below from https://github.com/the-modem-distro/pine...LASHING.md

Code:

mobian@mobian:~$ sudo adb reboot bootloader
* daemon not running; starting now at tcp:5037
* daemon started successfully
error: no devices/emulators found

same result as above when run as root