cfg/mac80211: add regulatory classes IE during TDLS setup

Seems Broadcom TDLS peers (Nexus 5, Xperia Z3) refuse to allow TDLS
connection when channel-switching is supported but the regulatory
classes IE is missing from the setup request.
Add a chandef to reg-class translation function to cfg80211 and use it
to add the required IE during setup. For now add only the current
regulatory class as supported - it is enough to resolve the
compatibility issue.

Signed-off-by: Arik Nemtsov <arikx.nemtsov@intel.com>
Signed-off-by: Emmanuel Grumbach <emmanuel.grumbach@intel.com>
Signed-off-by: Johannes Berg <johannes.berg@intel.com>

1 files changed, 21 insertions, 0 deletions

diff --git a/net/mac80211/tdls.c b/net/mac80211/tdls.c
index bc7e4049896f..79ed59acf0d4 100644
--- a/net/mac80211/tdls.c
+++ b/net/mac80211/tdls.c
@@ -136,6 +136,24 @@ ieee80211_tdls_add_supp_channels(struct ieee80211_sub_if_data *sdata,
         *pos = 2 * subband_cnt;
 }
 
+static void ieee80211_tdls_add_oper_classes(struct ieee80211_sub_if_data *sdata,
+                                            struct sk_buff *skb)
+{
+        u8 *pos;
+        u8 op_class;
+
+        if (!ieee80211_chandef_to_operating_class(&sdata->vif.bss_conf.chandef,
+                                                  &op_class))
+                return;
+
+        pos = skb_put(skb, 4);
+        *pos++ = WLAN_EID_SUPPORTED_REGULATORY_CLASSES;
+        *pos++ = 2; /* len */
+
+        *pos++ = op_class;
+        *pos++ = op_class; /* give current operating class as alternate too */
+}
+
 static void ieee80211_tdls_add_bss_coex_ie(struct sk_buff *skb)
 {
         u8 *pos = (void *)skb_put(skb, 3);
@@ -350,6 +368,8 @@ ieee80211_tdls_add_setup_start_ies(struct ieee80211_sub_if_data *sdata,
                 }
         }
 
+        ieee80211_tdls_add_oper_classes(sdata, skb);
+
         /*
          * with TDLS we can switch channels, and HT-caps are not necessarily
          * the same on all bands. The specification limits the setup to a
@@ -786,6 +806,7 @@ ieee80211_tdls_build_mgmt_packet_data(struct ieee80211_sub_if_data *sdata,
                                50 + /* supported channels */
                                3 + /* 40/20 BSS coex */
                                4 + /* AID */
+                               4 + /* oper classes */
                                extra_ies_len +
                                sizeof(struct ieee80211_tdls_lnkie));
         if (!skb)