Mechanism to enable/disable feature at boot

[DoubleVee73]

I am trying to work out how to toggle USB MSC on the rp2 port. I can manually change the MICROPY_HW_USB_MSC value in mpconfig.h but I am looking to enable/disable this feature at boot by reading the value of a pin input. I am developing a product whereby I would like it to present as MSC at boot if a user is pressing a button, to allow a config file to easily be out onto the product. The product then reboots without MSC support but is able to read the config file.

Can I turn this into a variable somehow and if so, what would be a good approach? I am hoping that USB gets further developed in the next release of MP on the rp2 but if I can solve the MSC question I will be able to move forward.

I am trying to move away from the previous prototype that was based on STM32F411 due to supply and cost challenges.