Re: [PATCH v2 3/5] mac80211: check if HT40+/- is allowed before sending assoc

["Luis R. Rodriguez" <lrodriguez@atheros.com>]

On Tue, Apr 07, 2009 at 03:11:11AM -0700, Johannes Berg wrote:
> On Mon, 2009-04-06 at 16:15 -0400, Luis R. Rodriguez wrote:
> > We weren't checking this at all.
> > 
> > Signed-off-by: Luis R. Rodriguez <lrodriguez@atheros.com>
> > ---
> >  net/mac80211/ht.c |    8 ++++++--
> >  1 files changed, 6 insertions(+), 2 deletions(-)
> > 
> > diff --git a/net/mac80211/ht.c b/net/mac80211/ht.c
> > index 4e3c72f..967367c 100644
> > --- a/net/mac80211/ht.c
> > +++ b/net/mac80211/ht.c
> > @@ -122,10 +122,14 @@ u32 ieee80211_enable_ht(struct ieee80211_sub_if_data *sdata,
> >  		    (hti->ht_param & IEEE80211_HT_PARAM_CHAN_WIDTH_ANY)) {
> >  			switch(hti->ht_param & IEEE80211_HT_PARAM_CHA_SEC_OFFSET) {
> >  			case IEEE80211_HT_PARAM_CHA_SEC_ABOVE:
> > -				channel_type = NL80211_CHAN_HT40PLUS;
> > +				if (!(local->hw.conf.channel->flags &
> > +				    IEEE80211_CHAN_NO_HT40PLUS))
> > +					channel_type = NL80211_CHAN_HT40PLUS;
> 
> This patch is not sufficient -- you also need to modify
> ieee80211_send_assoc. Otherwise we end up telling the AP that we support
> HT40, but tuning the hardware to HT20.

Like this?

                switch (ht_info->ht_param & IEEE80211_HT_PARAM_CHA_SEC_OFFSET) {
                case IEEE80211_HT_PARAM_CHA_SEC_ABOVE:
                        if (flags & IEEE80211_CHAN_NO_HT40PLUS) {
                                cap &= ~IEEE80211_HT_CAP_SUP_WIDTH_20_40;
                                cap &= ~IEEE80211_HT_CAP_SGI_40;
                        }
                        break;
                case IEEE80211_HT_PARAM_CHA_SEC_BELOW:
                        if (flags & IEEE80211_CHAN_NO_HT40MINUS) {
                                cap &= ~IEEE80211_HT_CAP_SUP_WIDTH_20_40;
                                cap &= ~IEEE80211_HT_CAP_SGI_40;
                        }
                    
  Luis