From 0aaffa9b9699894aab3266195a529baf9f96ac29 Mon Sep 17 00:00:00 2001 From: Johannes Berg Date: Wed, 5 May 2010 15:28:27 +0200 Subject: mac80211: improve HT channel handling Currently, when one interface switches HT mode, all others will follow along. This is clearly undesirable, since the new one might switch to no-HT while another one is operating in HT. Address this issue by keeping track of the HT mode per interface, and allowing only changes that are compatible, i.e. switching into HT40+ is not possible when another interface is in HT40-, in that case the second one needs to fall back to HT20. Also, to allow drivers to know what's going on, store the per-interface HT mode (channel type) in the virtual interface's bss_conf. Signed-off-by: Johannes Berg Signed-off-by: John W. Linville --- net/mac80211/chan.c | 70 +++++++++++++++++++++++++++++++++++++++++++++++++++++ 1 file changed, 70 insertions(+) (limited to 'net/mac80211/chan.c') diff --git a/net/mac80211/chan.c b/net/mac80211/chan.c index 08f3832..5d218c5 100644 --- a/net/mac80211/chan.c +++ b/net/mac80211/chan.c @@ -2,6 +2,7 @@ * mac80211 - channel management */ +#include #include "ieee80211_i.h" enum ieee80211_chan_mode @@ -55,3 +56,72 @@ ieee80211_get_channel_mode(struct ieee80211_local *local, return mode; } + +bool ieee80211_set_channel_type(struct ieee80211_local *local, + struct ieee80211_sub_if_data *sdata, + enum nl80211_channel_type chantype) +{ + struct ieee80211_sub_if_data *tmp; + enum nl80211_channel_type superchan = NL80211_CHAN_NO_HT; + bool result; + + mutex_lock(&local->iflist_mtx); + + list_for_each_entry(tmp, &local->interfaces, list) { + if (tmp == sdata) + continue; + + if (!ieee80211_sdata_running(tmp)) + continue; + + switch (tmp->vif.bss_conf.channel_type) { + case NL80211_CHAN_NO_HT: + case NL80211_CHAN_HT20: + superchan = tmp->vif.bss_conf.channel_type; + break; + case NL80211_CHAN_HT40PLUS: + WARN_ON(superchan == NL80211_CHAN_HT40MINUS); + superchan = NL80211_CHAN_HT40PLUS; + break; + case NL80211_CHAN_HT40MINUS: + WARN_ON(superchan == NL80211_CHAN_HT40PLUS); + superchan = NL80211_CHAN_HT40MINUS; + break; + } + } + + switch (superchan) { + case NL80211_CHAN_NO_HT: + case NL80211_CHAN_HT20: + /* + * allow any change that doesn't go to no-HT + * (if it already is no-HT no change is needed) + */ + if (chantype == NL80211_CHAN_NO_HT) + break; + superchan = chantype; + break; + case NL80211_CHAN_HT40PLUS: + case NL80211_CHAN_HT40MINUS: + /* allow smaller bandwidth and same */ + if (chantype == NL80211_CHAN_NO_HT) + break; + if (chantype == NL80211_CHAN_HT20) + break; + if (superchan == chantype) + break; + result = false; + goto out; + } + + local->_oper_channel_type = superchan; + + if (sdata) + sdata->vif.bss_conf.channel_type = chantype; + + result = true; + out: + mutex_unlock(&local->iflist_mtx); + + return result; +} -- cgit v1.1