I'm happy to take requests for specific drivers to be written, but there are a few things I ask for:
1) You MUST send me a copy of the protocol documentation. I simply don't have the time to reverse engineer protocols.
2) Ideally I need access to the device for development and testing. This could be a loan or a donation
If this isn't possible, then at the very least you must have full time access to the device. Testing is by far the most time consuming part of the development cycle.
3) Don't expect a driver within 24 hours. It takes time!
4) The more information you provide about the device the better. A direct link to the product documentation on the manufacturer's website is a good start.