Wikipedia
HostAP
HostAP is one of the most popular IEEE 802.11 device drivers for Linux. It works with cards using the Conexant (formerly Intersil) Prism 2/2.5/3 chipset and support Host AP mode, which allows a WLAN card to perform all the functions of a wireless access point.
The driver code was written by Jouni Malinen, hired by Atheros in 2008, and was included into the main kernel tree in Linux 2.6.14