Thanks cxz.I will check this source code(I am most interested in the kernel and all modules).A newer package SDK1224 (2013) can be found from here
The mirror for the old package SDK0809 (2013) doesn't work anymore.
Here is a new mirror. ( Thanks b0joker ! )
Source code packages for tablets having newer SOCs like 7029b/7021/gs702C are much more common.
They also contain files for our old 7029/gs702a. Here is one way to search them.
Source code of the kernel is incomplete! 80