An investigation by the Software Freedom Law Center (SFLC) has determined that OpenHAL -- which facilitates Linux wireless connections for LAN cards using Atheros Communications technology -- does not incorporate any elements that might infringe on copyrights held by Atheros.
"Our ultimate goal is to have full support for Atheros devices included in the Linux kernel," said Luis Rodriguez, a developer who works with Linux wireless technology, in a press release issued by SFLC. "By providing legal clearance, the Software Freedom Law Center has helped us get one step closer to making this a reality."
Open source wireless networking has been an ongoing can of worms. As Sune MÃÂ¸lgaard explained in a Linux.com article last February, "Getting wireless networking going under Linux can be a breeze or a hassle, depending on the network card or device you're using. Complicating matters is the fact that, especially for wireless network devices, manufacturers seem either unwilling or legally unable to provide even the most basic information for open source developers as to how the hardware should be operated by drivers."
The MadWifi project has been focused on developing Linux drivers for network cards using Atheros chips. The project had been working with a closed source hardware abstraction layer (HAL) -- "a kernel module that implements an API to present the hardware to the driver" -- from Atheros. OpenHAL is an open source version of a HAL, originally developed by Reyk Floeter for OpenBSD under the name ark5. Last fall, the SFLC completed an assessment of ark5 and vouched for its open source provenance, allowing development to continue unclouded by legal uncertainties.
Following charges earlier this year that OpenHAL contained elements that might infringe Atheros copyrights, MadWifi developers asked the SFLC to investigate. Today's announcement by the organization, which compared the OpenHAL code with the proprietary Atheros code and found no infringement, means MadWifi has been greenlighted to continue working on its Linux port. "The OpenHAL developers can now continue development with legal clarity," said Karen Sandler, an attorney at SFLC which provides pro bono legal assistance to the free and open source software community. They must, however, "continue their work in isolation from Atheros' proprietary code."