Book Review: Embedded Android

This is the review of the book, 'Embedded Android' by Karim Yaghmour, which is an essential reference for any developer doing customization of android platform. As I am an application and a device developer primarily when it comes to android or embedded device management respectively, I read this book as a novice attempting to glean some understanding of the android internals.





The first thing that struck me was the updated nature of the book wrt the android ecosystem and how some of the mystifying concepts of android were explained, like the comparison between gnu linux and its kernal and of dalvik with java and the algorithms employed by the OS for optimizing constrained resource devices. The next involved Karim taking me on a guided tour to the different parts of android that I did not imagined such as building and customization of the android SDK itself and custom roms for headless devices.

Make no mistake, this is not a book for android application development, or its native counterpart but explains you part-by-part about the different aspects involved in development of the android project.

Book contents

The book starts with the introduction of the android project's history and its differences with classical open source projects. It then dives deep into the internals of the android OS covering the architecture and comparing it with linux. It then covers dalvik and system services.
The next couple of chapters focus entirely on the android open source project and involves building of various components of the project. The build system of android is also discussed and compared with conventional makefile based systems. One considerable mention is the presence of build recipes and hacks that give more insight about what is being covered.
Hardware and popular systems are covered next and development on different boards and SOCs are covered in this chapter which is followed up by a thorough discussion of the filesystem, components as well as commonly used tools.
Finally the book discusses the android framework where different utilities, extension into support of newer hardware, components, services and parts of the android OS is covered.

The appendixes cover portions such as legacy user-space and adding support for new hardware as well as customizing the default lists of packages. The default init.rc files are also provided alongwith informative links to various websites that cover the latest in the topics that are covered in the book.

While I cannot honestly comment the usability of the book from an android modder/image customizer's point of view, in general I found the book to be of great use and armed with my preexisting knowledge of android development and linux, I was able to understand the topics very well.

Disclaimer: This book was provided to me by Oreilly as part of their blogger review program.

Repairing your problematic display drivers

I am sharing a recent experience with my laptop. It is a MSI CR-500 that houses an Nvidia GeForce 8200m G graphics card. In previous Ubuntu(11.04 and earlier) versions, the stock graphics driver resulted in suboptimal displays and compiz and other desktop polishing tools were not able to be installed.

Out of habit, I tried to install a custom Nvidia binary driver into my newly installed Ubuntu 12.04 last week but the graphics driver failed to install correctly. The newer linux kernal did not allow my exsiting drivers to install so had to download a newly released driver. Undaunted, I tried installing a new driver, but it failed and my graphics display manager went kaput.

To get the things back, I simply reinstalled the Ubuntu and got my settings back. Here's what I did:

Booted off 12.04 livecd/pen drive

• In install option window, went to manual drive partitioning option
• Selected the partition containing the 12.04 and set its mount point to /
• Did not select the format disk option – to retain my earlier settings and installations.

It gave me a warning specifying deletion of files.

The OS got restored in 20 minutes and I was good to go!

NOTE : Nothing much got deleted as I was having a fairly new OS with not much loaded components. Surprisingly, the java7 unzipped at /usr/local/lib was untouched, but the scala installed at /home/sumit was removed.

PC Gaming on Linux

Many people consider Linux as a serious OS for computing, but there is a fun aspect to it that is not really known as there is no marketing done for these games. However, for a moderate gamer, linux platform is satisfying especially if you are looking for playing games for your amusement without going too heavy on your wallet. Linux has also improved on the UI front considerably as now we can have some seriously GPU intensive graphics through out of box programs like compiz.

Cool 3D Desktop with Compiz

Those looking for a quick solution can use http://live.linux-gamers.net that allows you to create and start gaming from the live CD/USB directly.

In addition to the point and click games(like card based games),  you can have some serious fun with 3D games that PC gamers have become familiar with. Be it a fast paced action game like AssaultCube or a racing game like TuxKart, there are options for everyone.

TuxKart  : Funny racing game

AssaultCube : Fast paced action, a la Quake3 style

Thanks to ID software's initiative of providing a linux binary(and their stand on DirectX framework), we can install and play a game like DOOM3 on Linux http://sites.google.com/site/lgmscripts/scripts/games/doom-3 (which is definitively on my TODO list:)

There are certain caveats to this excercise too. Since my laptop has a Nvidia GeForce 8200MG card, I had to use a non open source binary driver as the cannonical one was not working well on Ubuntu. If you consider the freedom and the non presence of any cost/license, it forms a good overall personal entertainment package.