Fix Dell XPS 13 Backlight Brightness Not Adjustable And Trackpad Not Working Properly In Ubuntu 12.04 Or 12.10

Sputnik Kernel PPA is an official Canonical Hardware Enablement Team PPA that provides an updated Linux Kernel which fixes some Dell XPS 13 laptop issues on Ubuntu:

• Backlight brightness not adjustable by default on Dell XPS 13 laptops: bug #954661 (this fix may also work for other laptops with Intel graphics processor that are having this issue)
• 'Cypress Trackpad' incorrectly detected as 'ImPS/2 Generic Wheel Mouse' in 'Dell XPS 13 Ultrabook': bug #978807 - the Linux Kernel in the PPA provides experimental Cypress PS/2 Trackpad driver with multi-touch support (for Dell XPS 13 and other laptops with this trackpad).

Besides the issues above, there was another issue which caused Dell XPS 13 and Dell XPS 15 WiFi to be disabled when disabling the Bluetooth (and the other way around) that was fixed both into the kernel available in this PPA and in the Ubuntu 12.04 kernel, but apparently it wasn't fixed for Dell XPS 17 laptops too. To fix it manually, run the following commands in a terminal:

echo "#fix dell wifi/bluetooth:" | sudo tee -a /etc/modprobe.d/blacklist.conf
echo "blacklist dell_laptop" | sudo tee -a /etc/modprobe.d/blacklist.conf

Then, restart the laptop and the WiFi / Bluetooth should work normally.

Install the Sputnik Kernel in Ubuntu 12.04 or 12.10

To add the Sputnik Kernel PPA in Ubuntu 12.04 Precise Pangolin or 12.10 Quantal Quetzal and upgrade the Linux Kernel, use the following commands:

sudo add-apt-repository ppa:canonical-hwe-team/sputnik-kernel
sudo apt-get update
sudo apt-get upgrade

Once the upgrade is complete, restart the laptop.

For Arch Linux users, WebUpd8 reader dcelasun has created a custom kernel that uses these patches: https://aur.archlinux.org/packages.php?ID=60736

If for some reason you want to go back using the Linux Kernel from the official Ubuntu 12.04 / 12.10 repositories, use PPA Purge to purge the Sputnik Kernel PPA:

sudo apt-get install ppa-purge
sudo ppa-purge ppa:canonical-hwe-team/sputnik-kernel

image via pcper.com