Android has always been Linux, but for years the Android project went its own way and its code wasn’t merged back into the main Linux tree. Now, much sooner than Linus Torvalds, Linux’s founder and lead developer, had expected, Android has officially merged back into Linux’s mainline.
The fork between Android and Linux all began in the fall of 2010, “Google engineer Patrick Brady stated that Android is not Linux” That was never actually the case. Android has always been Linux at heart.
At the same time though Google did take Android in a direction that wasn’t compatible with the mainstream Linux kernel. As Greg Kroah-Hartman, the maintainer of the stable Linux kernel for the Linux Foundation and head of the Linux Driver Project, wrote in Android and the Linux kernel community, “The Android kernel code is more than just the few weird drivers that were in the drivers/staging/androidsubdirectory in the kernel. In order to get a working Android system, you need the new lock type they have created, as well as hooks in the core system for their security model. In order to write a driver for hardware to work on Android, you need to properly integrate into this new lock, as well as sometimes the bizarre security model. Oh, and then there’s the totally-different framebuffer driver infrastructure as well.” That flew like a lead balloon in Android circles.
This disagreement sprang from several sources. One was that Google’s Android developers had adopted their own way to address power issues with WakeLocks. The other cause, as Google open source engineering manager Chris DiBona pointed out, was that Android’s programmers were so busy working on Android device specifics that they had done a poor job of co-coordinating with the Linux kernel developers.
Source: http://www.zdnet.com/blog/open-source/android-and-linux-re-merge-into-one-operating-system/10625?tag=content;search-results-river















