Does anyone know the application/use of "wpa_driver_nl80211_remain_on_channel" API call present in nl80211 driver?
Does it function analogues to monitor mode in wifi??
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The remain on channel feature is used for implementing WiFi Peer-to-Peer (P2P) in Linux, see Linux Wireless wiki and slides from a talk by Johannes Berg held at the Linux Plumbers Conference 2010.
To my understanding, it simply instructs the lower layers to stay on the given channel at least for the given amount of time to make the reception of frames possible that do not belong to the current session between client and access point but are exchanged to set-up a P2P link.
In contrast, monitor mode is a feature that allows to receive all 802.11 frames received by the hardware no matter if they are addressed to the device and no matter which type they are of. The received frames are not mangled by the mac80211 stack and are passed to the userspace in their original 802.11 format. This feature is used (among other things) for diagnostic purposes.
Consequently, I would say that remain on channel and monitor mode are entirely distinct features. They may be used together e.g. to capture 802.11 frames on a particular channel and prevent the lower layers from switching away from this channel.
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