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+ <item>
+ <title>Using modalias info to find packages handling my hardware</title>
+ <link>http://people.skolelinux.org/pere/blog/Using_modalias_info_to_find_packages_handling_my_hardware.html</link>
+ <guid isPermaLink="true">http://people.skolelinux.org/pere/blog/Using_modalias_info_to_find_packages_handling_my_hardware.html</guid>
+ <pubDate>Tue, 15 Jan 2013 08:00:00 +0100</pubDate>
+ <description><p>Yesterday, I wrote about the
+<a href="http://people.skolelinux.org/pere/blog/Modalias_strings___a_practical_way_to_map__stuff__to_hardware.html">modalias
+values provided by the Linux kernel</a> following my hope for
+<a href="http://people.skolelinux.org/pere/blog/Lets_make_hardware_dongles_easier_to_use_in_Debian.html">better
+dongle support in Debian</a>. Using this knowledge, I have tested how
+modalias values attached to package names can be used to map packages
+to hardware. This allow the system to look up and suggest relevant
+packages when I plug in some new hardware into my machine, and replace
+discover and discover-data as the database used to map hardware to
+packages.</p>
+
+<p>I create a modaliases file with entries like the following,
+containing package name, kernel module name (if relevant, otherwise
+the package name) and globs matching the relevant hardware
+modalias.</p>
+
+<p><blockquote>
+Package: package-name
+<br>Modaliases: module(modaliasglob, modaliasglob, modaliasglob)</p>
+</blockquote></p>
+
+<p>It is fairly trivial to write code to find the relevant packages
+for a given modalias value using this file.</p>
+
+<p>An entry like this would suggest the video and picture application
+cheese for many USB web cameras (interface bus class 0E01):</p>
+
+<p><blockquote>
+Package: cheese
+<br>Modaliases: cheese(usb:v*p*d*dc*dsc*dp*ic0Eisc01ip*)</p>
+</blockquote></p>
+
+<p>An entry like this would suggest the pcmciautils package when a
+CardBus bridge (bus class 0607) PCI device is present:</p>
+
+<p><blockquote>
+Package: pcmciautils
+<br>Modaliases: pcmciautils(pci:v*d*sv*sd*bc06sc07i*)
+</blockquote></p>
+
+<p>An entry like this would suggest the package colorhug-client when
+plugging in a ColorHug with USB IDs 04D8:F8DA:</p>
+
+<p><blockquote>
+Package: colorhug-client
+<br>Modaliases: colorhug-client(usb:v04D8pF8DAd*)</p>
+</blockquote></p>
+
+<p>I believe the format is compatible with the format of the Packages
+file in the Debian archive. Ubuntu already uses their Packages file
+to store their mappings from packages to hardware.</p>
+
+<p>By adding a XB-Modaliases: header in debian/control, any .deb can
+announce the hardware it support in a way my prototype understand.
+This allow those publishing packages in an APT source outside the
+Debian archive as well as those backporting packages to make sure the
+hardware mapping are included in the package meta information. I've
+tested such header in the pymissile package, and its modalias mapping
+is working as it should with my prototype. It even made it to Ubuntu
+Raring.</p>
+
+<p>To test if it was possible to look up supported hardware using only
+the shell tools available in the Debian installer, I wrote a shell
+implementation of the lookup code. The idea is to create files for
+each modalias and let the shell do the matching. Please check out and
+try the
+<a href="http://anonscm.debian.org/viewvc/debian-edu/trunk/src/hw-support-handler/hw-support-lookup?view=co">hw-support-lookup</a>
+shell script. It run without any extra dependencies and fetch the
+hardware mappings from the Debian archive and the subversion
+repository where I currently work on my prototype.</p>
+
+<p>When I use it on a machine with a yubikey inserted, it suggest to
+install yubikey-personalization:</p>
+
+<p><blockquote>
+% ./hw-support-lookup
+<br>yubikey-personalization:
+<br>%
+</blockquote></p>
+
+<p>When I run it on my Thinkpad X40 with a PCMCIA/CardBus slot, it
+propose to install the pcmciautils package:</p>
+
+<p><blockquote>
+% ./hw-support-lookup
+<br>pcmciautils
+<br>%
+</blockquote></p>
+
+<p>If you know of any hardware-package mapping that should be added to
+<a href="http://anonscm.debian.org/viewvc/debian-edu/trunk/src/hw-support-handler/modaliases?view=co">my
+database</a>, please tell me about it.</p>
+
+<p>It could be possible to generate several of the mappings between
+packages and hardware. One source would be to look at packages with
+kernel modules, ie packages with *.ko files in /lib/modules/, and
+extract their modalias information. Another would be to look at
+packages with udev rules, ie packages with files in
+/lib/udev/rules.d/, and extract their vendor/model information to
+generate a modalias matching rule. I have not tested any of these to
+see if it work.</p>
+
+<p>If you want to help implementing a system to let us propose what
+packages to install when new hardware is plugged into a Debian
+machine, please send me an email or talk to me on
+<a href="irc://irc.debian.org/%23debian-devel">#debian-devel</a>.</p>
+</description>
+ </item>
+
<item>
<title>Modalias strings - a practical way to map "stuff" to hardware</title>
<link>http://people.skolelinux.org/pere/blog/Modalias_strings___a_practical_way_to_map__stuff__to_hardware.html</link>
</description>
</item>
- <item>
- <title>Ledger - double-entry accounting using text based storage format</title>
- <link>http://people.skolelinux.org/pere/blog/Ledger___double_entry_accounting_using_text_based_storage_format.html</link>
- <guid isPermaLink="true">http://people.skolelinux.org/pere/blog/Ledger___double_entry_accounting_using_text_based_storage_format.html</guid>
- <pubDate>Tue, 18 Dec 2012 23:30:00 +0100</pubDate>
- <description><p>A few days ago I came across
-<a href="http://joeyh.name/blog/entry/hledger/">a blog post from Joey
-Hess</a> describing <a href="http://ledger-cli.org/">ledger</a> and
-hledger, a text based system for double-entry accounting. I found it
-interesting, as I am involved with several organizations where
-accounting is an issue, and I have not really become too friendly with
-the different web based systems we use. I find it hard to find what I
-look for in the menus and even harder try to get sensible data out of
-the systems. Ledger seem different. The accounting data is kept in
-text files that can be stored in a version control system, and there
-
-are at least <a href="https://github.com/ledger/ledger/wiki/Ports">five
-different implementations</a> able to read the format. An example
-entry look like this, and is simple enough that it will be trivial to
-generate entries based on CVS files fetched from the bank:</p>
-
-<blockquote><pre>
-2004-05-27 Book Store
- Expenses:Books $20.00
- Liabilities:Visa
-</pre></blockquote>
-
-<p>The concept seemed interesting enough for me to check it out and
-look for others using it. I found blog posts from
-<a href="http://blog.spang.cc/posts/hledger_rocks_my_world/">Christine
-Spang</a>,
-<a href="http://bugsplat.info/2010-05-23-keeping-finances-with-ledger.html">Pete
-Keen</a>,
-<a href="http://blog.andrewcantino.com/blog/2010/11/06/command-line-accounting-with-ledger-and-reckon/">Andrew
-Cantino</a> and
-<a href="http://blog.iphoting.com/blog/2012/11/29/command-line-double-entry-accounting/">Ronald
-Ip</a> describing how they use it, as well as a post from
-<a href="https://groups.google.com/forum/?fromgroups=#!topic/ledger-cli/r0oWjwbQ9Bo">Bradley
-M. Kuhn</a> at the Software Freedom Conservancy. All seemed like good
-recommendations fitting my need.</p>
-
-<p>The <a href="http://packages.qa.debian.org/l/ledger.html">ledger</a>
-package is available in Debian Squeeze, while the
-<a href="http://packages.qa.debian.org/h/haskell-hledger.html">hledger</a>
-package only is available in Debian Sid. As I use Squeeze, ledger
-seemed the best choice to get started.</p>
-
-<p>To get some real data to test on, I wrote a
-<a href="http://www.nuug.no/tools/lodo2ledger">web scraper</a> for
-<a href="http://www.lodo.no/">LODO</a>, the accounting system used by
-the <a href="http://www.nuug.no/">NUUG</a> association, and started to
-play with the data set. I'm not really deeply into accounting, but I
-am able to get a simple balance and accounting status for example
-using the "<tt>ledger balance</tt>" command. But I will have to
-gather more experience before I know if the ledger way is a good fit
-for the organisations I am involved in.</p>
-</description>
- </item>
-
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