The Android kernel code is now removed from the Linux kernel, as of the 2.6.33 kernel release, as reported on the Linux kernel monkey log.

what happened with the Android kernel code that caused it to be deleted? According the Linux kernel monkey log Google didn't seem to care about the code anymore, so it was removed. Code in the staging tree needs to be worked on to be merged to the main kernel tree, or it will be deleted.

Here's a quote from the blog:

The Android kernel code is more than just the few weird drivers that were in the drivers/staging/android subdirectory 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.

This means that any drivers written for Android hardware platforms, can not get merged into the main kernel tree because they have dependencies on code that only lives in Google's kernel tree, causing it to fail to build in the kernel.org tree.

Because of this, Google has now prevented a large chunk of hardware drivers and platform code from ever getting merged into the main kernel tree. Effectively creating a kernel branch that a number of different vendors are now relying on.

Now branches in the Linux kernel source tree are fine and they happen with every distro release. But this is much worse. Because Google doesn't have their code merged into the mainline, these companies creating drivers and platform code are locked out from ever contributing it back to the kernel community. The kernel community has for years been telling these companies to get their code merged, so that they can take advantage of the security fixes, and handle the rapid API churn automatically. And these companies have listened, as is shown by the larger number of companies contributing to the kernel every release.

But now they are stuck. Companies with Android-specific platform and drivers can not contribute upstream, which causes these companies a much larger maintenance and development cycle.


You can read the complete article here.