ath9k

ath9k is the open-source Linux kernel driver for Atheros 802.11n wireless LAN devices. It supports a broad family of Atheros chipsets in the AR92x/AR93x/AR9k series, including PCI and PCIe devices used in laptops and embedded systems. The driver is part of the Linux wireless subsystem and relies on the mac80211 framework to provide common 802.11 functionality.

In terms of features, ath9k implements 802.11a/b/g/n operation with HT20 and HT40 support on compatible hardware, and supports MIMO configurations available on specific chipsets. It provides standard wireless capabilities such as client (station) mode, access point mode (through hostapd), monitor mode, and IBSS/ad-hoc networking. It supports channel and regulatory domain handling, power management, and basic QoS/traffic prioritization via the mac80211 stack.

Firmware and deployment: Some supported devices require a firmware binary to be loaded at runtime; the firmware is typically provided by the distribution or vendor packages and loaded by the kernel as part of device initialization.

Development and maintenance: The driver originated with Atheros Communications (now Qualcomm Atheros) and is maintained by the Linux wireless community as part of the kernel. It has undergone long-term support in mainline kernels, with ongoing updates for stability, performance, and regulatory compliance.

This article describes the driver generally; refer to kernel documentation and vendor hardware notes for exact chipset support and capabilities.