Today, Google Android Team released the source of the latest Ice Cream Sandwich OR Android 4.0. After Ginger bread, the source of HoneyComb is not released to public stating that, HoneyComb is a quick fix to Ginger Bread to work on Tablet. And Google assured that, ICS source will be released as an open source. Good to see Google did it.
The binary driver for different platforms supported by default in the source can found in the following link: http://code.google.com/intl/zh-CN/android/nexus/drivers.html