CAC question: DFS -> non-dfs -> DFS

2 messages, 2 authors, 2021-08-29 · open the first message on its own page

CAC question: DFS -> non-dfs -> DFS

From: Ben Greear <hidden>
Date: 2021-08-20 16:43:57

Hello,

While poking at the MTK driver and trying to fix some CAC bugs in it,
I noticed the following:

Select ch 100, which enables DFS CAC logic.  Wait for that to finish.
Then select CH 36 (disable DFS)
Then select ch 100 again, and the chandef->chan->dfs_state is set back to 0
which I think means we must do CAC again.

I was expecting in this case that the DFS state would be set to NL80211_DFS_AVAILABLE
instead, since CAC just passed a few minutes prior?

Thanks,
Ben

-- 
Ben Greear [off-list ref]
Candela Technologies Inc  http://www.candelatech.com

Re: CAC question: DFS -> non-dfs -> DFS

From: Janusz Dziedzic <hidden>
Date: 2021-08-29 17:56:36

pt., 20 sie 2021 o 18:45 Ben Greear [off-list ref] napisał(a):
Hello,

While poking at the MTK driver and trying to fix some CAC bugs in it,
I noticed the following:

Select ch 100, which enables DFS CAC logic.  Wait for that to finish.
Then select CH 36 (disable DFS)
Then select ch 100 again, and the chandef->chan->dfs_state is set back to 0
which I think means we must do CAC again.

I was expecting in this case that the DFS state would be set to NL80211_DFS_AVAILABLE
instead, since CAC just passed a few minutes prior?
This depends on DFS region (country).
EU allow preCAC - once you pass CAC then you can switch to other
channel and - the old one will be DFS_AVAILABLE - no need to do CAC
again.
All other regions don't allow preCAC - so each channel switch will
clear DFS_AVAILABLE and require CAC again.

BR
Janusz
Keyboard shortcuts
hback out one level
jnext message in thread
kprevious message in thread
ldrill in
Escclose help / fold thread tree
?toggle this help