I’ve worked on kernel projects before but today marks the day I submitted a patch myself. I cannot take full or even half credit for it because it is a backport of a driver from Linux 2.6 for Sierra Wireless modems.

Even though that might sound simple it still took me quite a bit of work to get it to work properly due to the subtle changes in the underlying USB stack. I had to struggle quite a bit with some nasty instabilities related to interrupts which in the end turned out to be double frees on 2.4 but not on 2.6

My LKML submission is available at: http://marc.info/?l=linux-usb&m=126392883122598&w=2
The patch is available from my site since apparently GMail botched some of the lines: http://www.dholm.com/files/sierra-2.4_1.7.16-1.patch

Apparently 2.4 only accepts stability and security patches these days so I don’t think it will get merged but if someone ever needs it the work has already been done. We are running it on uClinux 2.4.26 but the patch was made against 2.4.37.

If you ever need to graft two git repositories, i.e. you want to restore history from your previous VCS, “Using git to stitch together a broken subversion repository” is a good starting point. Git is amazing when it comes two this task but in my opinion it is poorly documented at best.

A presentation on Google Wave which is Google’s next gen communications platform.

“Uncle Bob” talks about what it means to be a software developer.

Rob Pike presents the concurrency model in his Newsqueak programming language using channels. This is a very interesting concept but in the Newsqueak implementation it is probably only suitable for high level application programming.

Computer Architecture: A Quantitative Approach by John L. Hennessy & David Pattersson

For quite a while I’ve wanted to know more about the inner workings of CPUs in order to better understand why certain things are the way they are, endianess for instance. I posed the question on what book to get on the subject over at Stack Overflow and one of the recommendations was “Computer Architecture: A Quantative Approach” which arrived today.

The book is rather heavy and the kind of book where you’d like to have a professor condence the important parts for you but it contains the important sections that I was looking for such as pipelining and caches.

Update:

Machine Language for Beginners by Richard Mansfield

I forgot to mention that I also ordered a copy of “Machine Language for Beginners” which is an introduction to assembly programming on the 6502. This is a classic book and it’s available online for free (linked through the cover image above).

The book is bound by a steel spiral like the one you find in standard writing pads and I’m quite afraid to damage it considering the paper is somewhat aged so chances are I will leave my copy be and read the online version instead.

At work we have some tooling done in .NET but like all compiled languages it is highly inflexible when you need to quickly hack up a simple tool for a one time job. After hearing my coworker rave about Python I decided to slowly transition to it in order to add the missing flexibility. A couple of days ago I needed to upgrade on of the tools which was in an especially poor state so as an excercise I started doing it in Python.

Originally I thought it would take me too long to come up with something useful but one thing led to another and all of a sudden I had an application which by far surpassed the poorly implemented one. I had my Python code in a separate Git repository from our tooling repository since I didn’t really expect it to turn into something useful but now I realized that the value of the new tool really warranted it to be imported and to superceed the old one. The problem I was faced with now was how to import my Git repo into the central tooling repo without losing its history.

After spending a while googling and just getting hits on how to use git-cvs or git-svn to “import” or “merge” your existing cvs/svn repo into a shiny new Git repo I decided to go to #git for some local help. There the user Ilari pointed me to in the right direction which was to use a Git subtree merge strategy. Googling that I immediately found “How to use the subtree merge strategy” which was precisely the solution I was looking for!

So far I have not found a single use case that I needed which Git doesn’t already cover.

This is a very touching story about and by Ron Avitzur when he was working on Graphing Calculator for Mac OS. Makes you wish you were actually there.

Yet another load of books arrived on Friday last week.

Zen and the Art of Motorcycle Maintenance by Robert M. Pirsig

A philosophical book on the concepts of quality. This books is very highly regarded in the software industry so I decided I better read it. It is about a motorcycle journey made by the author, his son and two friends during which he contemplates on various philosophical topics.

I’ve read through a few chapters so far and I must say that it is beautifully written and if you are like me you will probably want to get a motorcycle after reading this.

The Mythical Man-Month by Frederick P. Brooks

Another book seen as a must read by software developers. It covers topics on managing software projects and is organized as a series of essays based on the authors real-life experience from working at IBM on the System/360 and later OS/360 projects.

If you are in the software industry you have most likely heard about this book before.

Core Memory: A Visual Survey of Vintage Computers by John Alderman et. al.

Core Memory is a beautiful coffee table book which presents the reader with beautiful photographs of various vintage computers along with brief summaries. It covers such machines as ENIAC, the Apollo guidance computer and the all too famous Commodore 64.

So far I have only flicked through a couple of pages but the photographs are beautiful and high res. If you share my passion for vintage computers this book is a must.

Mazda 626 and Mx-6 Ford Probe Automotive Repair Manual by Jay Storer et. al.

It’s your run of the mill Haynes manual so it should need little introduction. I have a tugging sound somewhere in the steering system of my Mazda 626  so I decided to get the manual in order to make my life easier when fixing it.