Greg addresses the NDA issue too, and here are more details about the offer from his blog:
Yes, that's right, the Linux kernel community is offering all companies free Linux driver development. No longer do you have to suffer through all of the different examples in the Linux Device Driver Kit, or pick through the thousands of example drivers in the Linux kernel source tree trying to determine which one is the closest to what you need to do.
All that is needed is some kind of specification that describes how your device works, or the email address of an engineer that is willing to answer questions every once in a while. A few sample devices might be good to have so that debugging doesn't have to be done by email, but if necessary, that can be done.
In return, you will receive a complete and working Linux driver that is added to the main Linux kernel source tree. The driver will be written by some of the members of the Linux kernel developer community (over 1500 strong and growing). This driver will then be automatically included in all Linux distributions, including the "enterprise" ones. It will be automatically kept up to date and working through all Linux kernel API changes. This driver will work with all of the different CPU types supported by Linux, the largest number of CPU types supported by any operating system ever before in the history of computing.
As for support, the driver will be supported through email by the original developers, when they can help out, and by the "enterprise" Linux distributors as part of their service agreements with their customers.
If your company is worried about NDA issues surrounding your device's specifications, we have arranged a program with OSDL/TLF's Tech Board to provide the legal framework where a company can interact with a member of the kernel community in order to properly assure that all needed NDA requirements are fulfilled.
Now your developers will have more time to work on drivers for all of the other operating systems out there, and you can add "supported on Linux" to your product's marketing material.
This offer is in effect for all different types of devices, from USB toys to PCI video devices to high-speed networking cards. If you manufacture it, we can get Linux drivers working for it.