Category: kernel

* This HOWTO document is placed under the public domain.
* You are free to copy, mirror, link to, or duplicate it.

This HOWTO is mirrored in two places:

* http://www.halibutdepot.org/how_to_build_rt3090_for_ubuntu_lucid/
* http://stat.case.edu/~jrt32/how_to_build_rt3090_for_ubuntu_lucid/

I have an MSI Wind U230 laptop.  The built-in wireless NIC identifies itself
as an "RaLink RT3090 Wireless 802.11n 1T/1R PCIe".  This NIC is not supported
out-of-the-box under Ubuntu 10.04 LTS (Lucid Lynx) because there is no
driver for it in the 2.6.32-22-generic kernel tree.

I searched for a solution and found that other people who are running
Lucid Lynx and using the same unsupported rt3090 NIC are getting it to work
by using the old version of the rt3090 driver packaged by Markus Heberling
in his PPA (https://launchpad.net/~markus-tisoft/+archive/rt3090).

I'm grateful to Markus Heberling for doing all of the hard work
to package RaLink's driver for Ubuntu.  But because his PPA for
the rt3090 has not been updated since Ubuntu 9.10 (Karmic Koala),
and because RaLink has released a newer version 2.3.1.4 that no one
has packaged, I don't feel comfortable relying on the old rt3090
package built for Karmic, even though it does work fine on Lucid.

Below I describe the procedure I used in order to build an rt3090-dkms
package just like the one that Markus Heberling built for Karmic Koala.
The process involves downloading the newest rt3090 driver from RaLink
(version 2.3.1.4 at the time of this writing), applying Markus Heberling's
patches against it, and building a package from the source.

Here is the procedure:

 (1) Install packages required to build packages.
     (a) sudo apt-get install build-essential
     (b) sudo apt-get install devscripts
     (c) sudo apt-get install cdbs

 (2) Define a root directory in which to download files.
     (a) cd /path/to/some/download/directory/
     (b) export DOWNLOAD=`pwd`

 (3) Get the rt3090 drivers from the manufacturer's website.
     (a) Option 1: Use the pre-saved RaLink tarball from
         http://stat.case.edu/~jrt32/how_to_build_rt3090_for_ubuntu_lucid/RT3090_LinuxSTA_V2.3.1.4_20100222.tar.bz2
     (b) Option 2: Download the tarball directly from RaLink:
         Go to http://eng.ralinktech.com.tw/support.php?s=2
     (c) Download the file "RT3090PCIe".
         (RT3090_LinuxSTA_V2.3.1.4_20100222.tar.bz2)

 (4) Get Markus Heberling's Ubuntu-friendly patches against RaLink's driver tarball.
     (a) Option 1: Download a mirrored copy of Markus Heberling's patch:
         http://stat.case.edu/~jrt32/how_to_build_rt3090_for_ubuntu_lucid/rt3090_2.3.1.3-0ubuntu0~ppa1.diff.gz
     (b) Option 2: Download the patches from Markus Heberling's PPA:
         Browse to https://launchpad.net/~markus-tisoft/+archive/rt3090/+packages
     (c) Expand the release "rt3090 - 1:2.3.1.3-0ubuntu0~ppa1".
     (d) Download the patch "rt3090_2.3.1.3-0ubuntu0~ppa1.diff.gz"

 (5) Get my patch to bump the packaged version number to 2.3.1.4 .
     (a) Download this patch:
         http://stat.case.edu/~jrt32/how_to_build_rt3090_for_ubuntu_lucid/rt3090-2.3.1.3-2.3.1.4.diff

 (6) Apply patches against RaLink's drivers.
     (a) Create a staging directory:
         mkdir -p /path/to/some/staging/directory
         cd /path/to/some/staging/directory
         export STAGING=`pwd`

     (b) Extract RaLink's drivers to the staging directory.
         cd $STAGING
         tar xfj $DOWNLOAD/RT3090_LinuxSTA_V2.3.1.4_20100222.tar.bz2
         cd $STAGING/RT3090_LinuxSTA_V2.3.1.4_20100222/

     (c) Apply Markus' patches to the extracted sources.
         cd $STAGING/RT3090_LinuxSTA_V2.3.1.4_20100222/
         gzip -dc $DOWNLOAD/rt3090_2.3.1.3-0ubuntu0~ppa1.diff.gz | patch -p1

     (d) Update the version number from 2.3.1.3 to 2.3.1.4 .
         cd $STAGING/RT3090_LinuxSTA_V2.3.1.4_20100222/
         patch -p1 < $DOWNLOAD/rt3090-2.3.1.3-2.3.1.4.diff

 (7) Build a DKMS-friendly .deb package.
     (a) cd $STAGING/RT3090_LinuxSTA_V2.3.1.4_20100222/
     (b) dpkg-buildpackage -A -sa -us -uc
     (c) An installable .deb package gets created and stored as
         $STAGING/rt3090-dkms_2.3.1.4-0ubuntu0~ppa1_all.deb
     (d) Optional: You may download my pre-built rt3090-dkms package here:
         http://stat.case.edu/~jrt32/how_to_build_rt3090_for_ubuntu_lucid/rt3090-dkms_2.3.1.4-0ubuntu0~ppa1_all.deb

 (8) Install the newly-built package.
     (a) sudo dpkg -i $STAGING/rt3090-dkms_2.3.1.4-0ubuntu0~ppa1_all.deb
     (b) sudo reboot

 (9) Appendix: Automatically rebuilding the module via DKMS.
     Sometimes I switch to a different kernel (such as the one provided
     in the package "linux-rt").  This breaks the wireless NIC because
     the module hasn't yet been built and installed in the new kernel.
     Because we built a DKMS module, we can have it rebuilt automatically
     after we reboot into a new kernel:
     (a) sudo dkms build -m rt3090 -v 2.3.1.4
     (b) sudo dkms install -m rt3090 -v 2.3.1.4