Open Source Summit Europe 2025

WiFi is a cornerstone of modern connectivity, and Linux powers countless devices that rely on seamless wireless communication. But how does a WiFi driver actually work within the Linux kernel? In this talk, we will explore the process of supporting a Wifi device in Linux, focusing on its integration with the mac80211 and cfg80211 subsystems. We’ll cover key aspects such as hardware initialization, packet transmission, regulatory compliance, power management, and more. Additionally, we’ll discuss how userspace tools like iw, hostapd, and wpa_supplicant interact with kernel drivers via nl80211. By the end of this session, attendees will have a better understanding of the Linux WiFi stack and the skills needed to develop, debug, and extend WiFi drivers effectively, whether they want to implement a new one or improve an existing one.