nl80211/cfg80211: support VHT channel configuration

Change nl80211 to support specifying a VHT (or HT)
using the control channel frequency (as before) and
new attributes for the channel width and first and
second center frequency. The old channel type is of
course still supported for HT.

Also change the cfg80211 channel definition struct
to support these by adding the relevant fields to
it (and removing the _type field.)

This also adds new helper functions:
 - cfg80211_chandef_create to create a channel def
   struct given the control channel and channel type,
 - cfg80211_chandef_identical to check if two channel
   definitions are identical
 - cfg80211_chandef_compatible to check if the given
   channel definitions are compatible, and return the
   wider of the two

This isn't entirely complete, but that doesn't matter
until we have a driver using it. In particular, it's
missing
 - regulatory checks on the usable bandwidth (if that
   even makes sense)
 - regulatory TX power (database can't deal with it)
 - a proper channel compatibility calculation for the
   new channel types

Signed-off-by: Johannes Berg <johannes.berg@intel.com>

1 files changed, 7 insertions, 6 deletions

diff --git a/net/mac80211/ibss.c b/net/mac80211/ibss.c
index bed616fd97e..5648bbed240 100644
--- a/net/mac80211/ibss.c
+++ b/net/mac80211/ibss.c
@@ -52,6 +52,7 @@ static void __ieee80211_sta_join_ibss(struct ieee80211_sub_if_data *sdata,
 	u32 bss_change;
 	u8 supp_rates[IEEE80211_MAX_SUPP_RATES];
 	struct cfg80211_chan_def chandef;
+	enum nl80211_channel_type chan_type;
 
 	lockdep_assert_held(&ifibss->mtx);
 
@@ -79,13 +80,13 @@ static void __ieee80211_sta_join_ibss(struct ieee80211_sub_if_data *sdata,
 
 	sdata->drop_unencrypted = capability & WLAN_CAPABILITY_PRIVACY ? 1 : 0;
 
-	chandef.chan = chan;
-	chandef._type = ifibss->channel_type;
+	chan_type = ifibss->channel_type;
+	cfg80211_chandef_create(&chandef, chan, chan_type);
 	if (!cfg80211_reg_can_beacon(local->hw.wiphy, &chandef))
-		chandef._type = NL80211_CHAN_HT20;
+		chan_type = NL80211_CHAN_HT20;
 
 	ieee80211_vif_release_channel(sdata);
-	if (ieee80211_vif_use_channel(sdata, chan, chandef._type,
+	if (ieee80211_vif_use_channel(sdata, chan, chan_type,
 				      ifibss->fixed_channel ?
 					IEEE80211_CHANCTX_SHARED :
 					IEEE80211_CHANCTX_EXCLUSIVE)) {
@@ -159,7 +160,7 @@ static void __ieee80211_sta_join_ibss(struct ieee80211_sub_if_data *sdata,
 		       ifibss->ie, ifibss->ie_len);
 
 	/* add HT capability and information IEs */
-	if (chandef._type != NL80211_CHAN_NO_HT &&
+	if (chan_type != NL80211_CHAN_NO_HT &&
 	    sband->ht_cap.ht_supported) {
 		pos = skb_put(skb, 4 +
 				   sizeof(struct ieee80211_ht_cap) +
@@ -172,7 +173,7 @@ static void __ieee80211_sta_join_ibss(struct ieee80211_sub_if_data *sdata,
 		 * keep them at 0
 		 */
 		pos = ieee80211_ie_build_ht_oper(pos, &sband->ht_cap,
-						 chan, chandef._type, 0);
+						 chan, chan_type, 0);
 	}
 
 	if (local->hw.queues >= IEEE80211_NUM_ACS) {