Re: [PATCH] mac80211: check if channels allow 80 MHz for VHT probe requests

[Johannes Berg <johannes@sipsolutions.net>]

On Tue, 2014-11-25 at 22:13 +0800, YanBo wrote:

> > But is all of that really the right way? I'm not completely convinced.
> 
> Except set the flag, the HW itself should support this feature, or
> else it also doesn't work, I'd
> send the patch in soon for public review.

Yeah, but is it really the right way to advertise VHT? In the spec, VHT
means you also have 80 MHz support - do you really think you can/will do
80 MHz on 2.4 GHz? Seems like all of this will cause more corner cases.

> >
> > I guess we can make this check conditional for 5GHz when the VHT support
> > lands and is discussed.
> >
> That is sounds good if it only check for 5GHz for what I know CMIIW.

Even on 2.4 GHz it technically isn't enough though - there's enough
spectrum in 2.4 GHz for a single 80 MHz channel; how long until somebody
wants to do *that* for some reason? But the rest of us really doesn't
think that's applicable ...

Anyway, it probably needs mac80211 patches anyway since mlme.c already
disables VHT if you can't do 80 MHz, so I think you should post those as
part of a bigger discussion about how we want to support it and what it
really means etc.

johannes