DMARC-Filter: OpenDMARC Filter v1.3.2 mail.kernel.org A191920C0A
Subject: Re: [PATCH] New functionality for aborting ongoing CAC.
To:     Enrique Giraldo <hgiraldos@gmail.com>
References: <20180925081933.28553-1-enrique.giraldo@galgus.net>
 <57143da1-1569-bd98-70e9-91cdcd89d1b8@broadcom.com>
 <CAEbaMQ+N=hUwXta9NbrBpF3YcoCyUNWB=s3cynp4pzFLuFrmDA@mail.gmail.com>
Cc:     linux-wireless@vger.kernel.org,
        Enrique Giraldo <enrique.giraldo@galgus.net>
From:   Arend van Spriel <arend.vanspriel@broadcom.com>
Message-ID: <1ff1f335-6962-4ace-6b25-562dab939893@broadcom.com>
Date:   Tue, 25 Sep 2018 11:53:34 +0200
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On 9/25/2018 11:28 AM, Enrique Giraldo wrote:
> The main reason is to be able to stop the CAC when you want to make a
> channel switch and the CAC is ongoing. It's true that the radio would
> not pass to the next phase, the behavior is the same as when during
> the CAC a radar event is detected. In the case of aborting, a later
> action is expected, for example, switch to the desired new channel.

So for mac80211 the function ieee80211_dfs_cancel_cac() indeed seems to 
just abort. So what is the scenario here? If user-space sends 
NL80211_CMD_START_AP with DFS channel, a CAC period is started. So you 
are saying you want to do a channel switch? Does it not make sense to 
issue a NL80211_CMD_STOP_AP and then NL80211_CMD_START_AP for the 
desired channel? Maybe the use-case you are looking at is not AP mode, 
but there is no context whatsoever in the commit message so I can only 
guess.

Regards,
Arend