[LAD] Novation launchpad midi driver

Christian krampenschiesser at freenet.de
Fri Apr 30 09:20:51 UTC 2010

Although my provider's spam filter still blocks linux audio mails, I'm 
happy to announce my novation launchpad midi driver.

It is not a driver in the common sense, but a user space usb application 
which offers a midi out and in to write and receive launchpad midi messages.
On my distribution(gentoo) I needed to add myself to the usb group to 
run this application.

Download it from: http://krampenschiesser.de/launchpadd-0.1.tar.bz2

I know the dependencies are quite fat(boost) but this driver is part of 
my sequencer application, and I just want to give launchpad owners the 
possibility to use their pad.

boost >= 1.41 (need threads, signals2, foreach)
To build the whole stuff you need cmake(>=2.6).

$ tar -xjf launchpadd-0.1.tar.bz2
$ cmake
$ make
$ sudo make install
$ launchpadmidid

To uninstall use :
$ xargs rm < install_manifest.txt

I would be very happy to get some feedback from the users and developers.
Coming from the Java world this is my first(finished) project in c++ and c.
And I didn't know anything about USB before...
So if there is a developer who has got a good knowledge of c/c++ or usb 
interrupt transfers it would be great if he could have a look at the 
code, especially the method handleWriteTransfer in LaunchpadImpl(.cpp) 
is a point where I'm not that sure about the interrupt handling(although 
it works as it is right now).

If there's anyone using this application on a kernel <=2.6.27 please 
inform me(as the polling changed with this version).

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