Google never opened Android 3.0 (Honeycomb) source code. It was probably because this OS was only meant to be used with tablets and they feared people would try to use it on smartphone.
The good news is that Android 4.0 (ICS) source code will be made available once the Galaxy Nexus ships. Although I’m not sure what license will be used with Android 4.0, that follows exactly the GPL license requirements since you don’t need to release the source code if you don’t provide the binaries.
See Jean-Baptiste Queru (Android Open Source Project ) announcement at https://plus.google.com/112218872649456413744/posts/HB5qQHeNKBQ.
In the meantime, the GPL source files that match the Android 4.0 / r14 SDK have been made available:
- Kernel: https://dl.google.com/dl/android/gpl/android-gpl-kernel-sdk-4.0.1_r1.tgz
- Platform: https://dl.google.com/dl/android/gpl/android-gpl-platform-sdk-arm-4.0.1_r1.tgz
- Dev Tools: https://dl.google.com/dl/android/gpl/android-gpl-tools_r14.tgz
- Extra: https://dl.google.com/dl/android/gpl/android-extra-4.0.1-r14.tgz
Like the Android did for all Honeycomb release, this is NOT the full source tree for Android 4.0 (ICS), these are only the GPL parts that are in the SDK (along with a few associated files), and they’re not enough to build the whole Android 4.0 for a device.