cfg80211 is the Linux wireless LAN (802.11) configuration API. Enable this if you have a wireless device. For more information refer to documentation on the wireless wiki: http://wireless.kernel.org/en/developers/Documentation/cfg80211 When built as a module it will be called cfg80211.
The nl80211 testmode command helps implementing things like factory calibration or validation tools for wireless chips. Select this option ONLY for kernels that are specifically built for such purposes. Debugging tools that are supposed to end up in the hands of users should better be implemented with debugfs. Say N.
This option enables some additional warnings that help cfg80211 developers and driver developers, but that can trigger due to races with userspace. For example, when a driver reports that it was disconnected from the AP, but the user disconnects manually at the same time, the warning might trigger spuriously due to races. Say Y only if you are developing cfg80211 or a driver based on it (or mac80211).
You can enable this if you want to debug regulatory changes. For more information on cfg80211 regulatory refer to the wireless wiki: http://wireless.kernel.org/en/developers/Regulatory If unsure, say N.
This option enables powersave mode by default. If this causes your applications to misbehave you should fix your applications instead -- they need to register their network latency requirement, see Documentation/power/pm_qos_interface.txt.
You can enable this if you want to debugfs entries for cfg80211. If unsure, say N.
This option generates an internal data structure representing the wireless regulatory rules described in net/wireless/db.txt and includes code to query that database. This is an alternative to using CRDA for defining regulatory rules for the kernel. For details see: http://wireless.kernel.org/en/developers/Regulatory Most distributions have a CRDA package. So if unsure, say N.
Enable this option if you need old userspace for wireless extensions with cfg80211-based drivers.
This option enables the deprecated wireless statistics files in /sys/class/net/*/wireless/. The same information is available via the ioctls as well. Say Y if you have programs using it, like old versions of hal.
This options enables a library of common routines used by IEEE802.11 wireless LAN drivers. Drivers should select this themselves if needed. Say Y if you want this built into your kernel.
You can enable this if you want verbose debugging messages from lib80211. If unsure, say N.