[MAC80211]: implement ERP info change notifications

zd1211rw and bcm43xx are interested in being notified when ERP IE conditions
change, so that they can reprogram a register which affects how control frames
are transmitted.

This patch adds an interface similar to the one that can be found in softmac.

Signed-off-by: Daniel Drake <dsd@gentoo.org>
Signed-off-by: Jiri Benc <jbenc@suse.cz>
Signed-off-by: John W. Linville <linville@tuxdriver.com>

5 files changed, 51 insertions, 10 deletions

diff --git a/include/net/mac80211.h b/include/net/mac80211.h
index 3282038a1510..e503cd37f82e 100644
--- a/include/net/mac80211.h
+++ b/include/net/mac80211.h
@@ -697,6 +697,14 @@ struct ieee80211_ops {
         void (*sta_table_notification)(struct ieee80211_hw *hw,
                                        int num_sta);
 
+        /* Handle ERP IE change notifications. Must be atomic. */
+        void (*erp_ie_changed)(struct ieee80211_hw *hw, u8 changes,
+                               int cts_protection, int preamble);
+
+        /* Flags for the erp_ie_changed changes parameter */
+#define IEEE80211_ERP_CHANGE_PROTECTION (1<<0) /* protection flag changed */
+#define IEEE80211_ERP_CHANGE_PREAMBLE (1<<1) /* barker preamble mode changed */
+
         /* Configure TX queue parameters (EDCF (aifs, cw_min, cw_max),
          * bursting) for a hardware TX queue.
          * queue = IEEE80211_TX_QUEUE_*.
diff --git a/net/mac80211/ieee80211.c b/net/mac80211/ieee80211.c
index f811a260ee9c..4715a9525918 100644
--- a/net/mac80211/ieee80211.c
+++ b/net/mac80211/ieee80211.c
@@ -464,8 +464,10 @@ static int ieee80211_open(struct net_device *dev)
         if (sdata->type == IEEE80211_IF_TYPE_MNTR) {
                 local->monitors++;
                 local->hw.conf.flags |= IEEE80211_CONF_RADIOTAP;
-        } else
+        } else {
                 ieee80211_if_config(dev);
+                ieee80211_reset_erp_info(dev);
+        }
 
         if (sdata->type == IEEE80211_IF_TYPE_STA &&
             !local->user_space_mlme)
@@ -748,6 +750,27 @@ int ieee80211_hw_config(struct ieee80211_local *local)
         return ret;
 }
 
+void ieee80211_erp_info_change_notify(struct net_device *dev, u8 changes)
+{
+        struct ieee80211_local *local = wdev_priv(dev->ieee80211_ptr);
+        struct ieee80211_sub_if_data *sdata = IEEE80211_DEV_TO_SUB_IF(dev);
+        if (local->ops->erp_ie_changed)
+                local->ops->erp_ie_changed(local_to_hw(local), changes,
+                                           sdata->use_protection,
+                                           !sdata->short_preamble);
+}
+
+void ieee80211_reset_erp_info(struct net_device *dev)
+{
+        struct ieee80211_sub_if_data *sdata = IEEE80211_DEV_TO_SUB_IF(dev);
+
+        sdata->short_preamble = 0;
+        sdata->use_protection = 0;
+        ieee80211_erp_info_change_notify(dev,
+                                         IEEE80211_ERP_CHANGE_PROTECTION |
+                                         IEEE80211_ERP_CHANGE_PREAMBLE);
+}
+
 struct dev_mc_list *ieee80211_get_mc_list_item(struct ieee80211_hw *hw,
                                                struct dev_mc_list *prev,
                                                void **ptr)
diff --git a/net/mac80211/ieee80211_i.h b/net/mac80211/ieee80211_i.h
index b0af6e9f5319..cc9999cd089c 100644
--- a/net/mac80211/ieee80211_i.h
+++ b/net/mac80211/ieee80211_i.h
@@ -788,6 +788,8 @@ struct sta_info * ieee80211_ibss_add_sta(struct net_device *dev,
                                          u8 *addr);
 int ieee80211_sta_deauthenticate(struct net_device *dev, u16 reason);
 int ieee80211_sta_disassociate(struct net_device *dev, u16 reason);
+void ieee80211_erp_info_change_notify(struct net_device *dev, u8 changes);
+void ieee80211_reset_erp_info(struct net_device *dev);
 
 /* ieee80211_iface.c */
 int ieee80211_if_add(struct net_device *dev, const char *name,
diff --git a/net/mac80211/ieee80211_ioctl.c b/net/mac80211/ieee80211_ioctl.c
index 8292431ac48f..1fde214faecb 100644
--- a/net/mac80211/ieee80211_ioctl.c
+++ b/net/mac80211/ieee80211_ioctl.c
@@ -1054,17 +1054,21 @@ static int ieee80211_ioctl_prism2_param(struct net_device *dev,
                 break;
 
         case PRISM2_PARAM_CTS_PROTECT_ERP_FRAMES:
-                if (sdata->type != IEEE80211_IF_TYPE_AP)
+                if (sdata->type == IEEE80211_IF_TYPE_AP) {
+                        sdata->use_protection = !!value;
+                        ieee80211_erp_info_change_notify(dev, IEEE80211_ERP_CHANGE_PROTECTION);
+                } else {
                         ret = -ENOENT;
-                else
-                        sdata->use_protection = value;
+                }
                 break;
 
         case PRISM2_PARAM_PREAMBLE:
-                if (sdata->type != IEEE80211_IF_TYPE_AP)
+                if (sdata->type != IEEE80211_IF_TYPE_AP) {
+                        sdata->short_preamble = !!value;
+                        ieee80211_erp_info_change_notify(dev, IEEE80211_ERP_CHANGE_PREAMBLE);
+                } else {
                         ret = -ENOENT;
-                else
-                        sdata->short_preamble = value;
+                }
                 break;
 
         case PRISM2_PARAM_STAT_TIME:
diff --git a/net/mac80211/ieee80211_sta.c b/net/mac80211/ieee80211_sta.c
index 0f5f8131bd71..33414f160538 100644
--- a/net/mac80211/ieee80211_sta.c
+++ b/net/mac80211/ieee80211_sta.c
@@ -319,6 +319,7 @@ static void ieee80211_handle_erp_ie(struct net_device *dev, u8 erp_value)
         struct ieee80211_if_sta *ifsta = &sdata->u.sta;
         int use_protection = (erp_value & WLAN_ERP_USE_PROTECTION) != 0;
         int preamble_mode = (erp_value & WLAN_ERP_BARKER_PREAMBLE) != 0;
+        u8 changes = 0;
 
         if (use_protection != sdata->use_protection) {
                 if (net_ratelimit()) {
@@ -329,6 +330,7 @@ static void ieee80211_handle_erp_ie(struct net_device *dev, u8 erp_value)
                                MAC_ARG(ifsta->bssid));
                 }
                 sdata->use_protection = use_protection;
+                changes |= IEEE80211_ERP_CHANGE_PROTECTION;
         }
 
         if (!preamble_mode != sdata->short_preamble) {
@@ -341,7 +343,11 @@ static void ieee80211_handle_erp_ie(struct net_device *dev, u8 erp_value)
                                MAC_ARG(ifsta->bssid));
                 }
                 sdata->short_preamble = !preamble_mode;
+                changes |= IEEE80211_ERP_CHANGE_PREAMBLE;
         }
+
+        if (changes)
+                ieee80211_erp_info_change_notify(dev, changes);
 }
 
 
@@ -400,7 +406,6 @@ static void ieee80211_set_associated(struct net_device *dev,
                                      struct ieee80211_if_sta *ifsta, int assoc)
 {
         union iwreq_data wrqu;
-        struct ieee80211_sub_if_data *sdata = IEEE80211_DEV_TO_SUB_IF(dev);
 
         if (ifsta->associated == assoc)
                 return;
@@ -428,8 +433,7 @@ static void ieee80211_set_associated(struct net_device *dev,
                 ieee80211_sta_send_associnfo(dev, ifsta);
         } else {
                 netif_carrier_off(dev);
-                sdata->short_preamble = 0;
-                sdata->use_protection = 0;
+                ieee80211_reset_erp_info(dev);
                 memset(wrqu.ap_addr.sa_data, 0, ETH_ALEN);
         }
         wrqu.ap_addr.sa_family = ARPHRD_ETHER;