driver user space communication in wpa_supplicant

[Dan Williams]

On Tue, 2010-06-29 at 23:57 +0530, sandeep kumar wrote:
> Hi All,
>   When using wext to notify eventts from driver to supplicant.
> What IPC is used for this purpose. If netlink sockets are used, please
> point me to the necessary API for it.

WEXT is an older kernel API that does not support a lot of the newer
features like 802.11n and fine-grained control of association and
scanning.  You probably don't want to use it.

Instead, you want to use nl80211 (the module for communication of WiFi
stuff over netlink)and cfg80211 (implements specific commands using
nl80211 for configuring WiFi devices) in your kernel driver.  The code
for both of these is in net/wireless/ in the kernel sources.

If you base your driver on the mac80211 softmac stack you get all this
for free.  If your driver is more fullmac/thickmac based, there are
various examples of conversions from WEXT to cfg80211 in the kernel
sources, most notably the 'orinoco' and 'rndis_wlan' drivers.

Dan