Fail to connect to FT232R USB UART in user space in NixOS

[ilidur]

Hello, thanks for a great project!

I wanted to see if I can resolve an issue I'm having with running a generic FT232R USB DMX device in user space. I'm running NixOS with the following settings:
user is in dialout group
start `nix-shell -p qlcplus usbutils`

If I run `qlcplus -d 1` it reports the following:

Code: Select all

virtual bool LibFTDIInterface::open() "" usb_open() failed
virtual bool LibFTDIInterface::clearRts() "" USB device unavailable

And in the Inputs I can see an entry for DMX USB, however it has no name (or gibberish) and no S/N.

however if I run exactly the same but with sudo: `sudo qlcplus -d 1`
I get no errors and the device reports as `FT232R USB UART (S/N: redacted)`

my device loads as `crw-rw---- 1 root dialout 188, 0 May 23 00:08 /dev/ttyUSB0`

I did a diff of `udevadm test` and I'm not sure if this is relevant however by running with and without sudo I get the following diff:
`Failed to read $container of PID 1, ignoring: Permission denied`

Is there an easy thing in my config that I missed? I'd like to see if I can write a nix build that has the correct settings and allows qlcplus to run as the user.