8 files changed, 63 insertions, 43 deletions

diff --git a/drivers/net/wireless/ath/carl9170/main.c b/drivers/net/wireless/ath/carl9170/main.c
index ef82751722e0..f293b3ff4756 100644
--- a/drivers/net/wireless/ath/carl9170/main.c
+++ b/drivers/net/wireless/ath/carl9170/main.c
@@ -1853,7 +1853,7 @@ void *carl9170_alloc(size_t priv_size)
                      IEEE80211_HW_REPORTS_TX_ACK_STATUS |
                      IEEE80211_HW_SUPPORTS_PS |
                      IEEE80211_HW_PS_NULLFUNC_STACK |
-                     IEEE80211_HW_NEED_DTIM_PERIOD |
+                     IEEE80211_HW_NEED_DTIM_BEFORE_ASSOC |
                      IEEE80211_HW_SIGNAL_DBM;
 
         if (!modparam_noht) {
diff --git a/drivers/net/wireless/iwlegacy/4965-mac.c b/drivers/net/wireless/iwlegacy/4965-mac.c
index f1dc04006564..d3cc776d2d34 100644
--- a/drivers/net/wireless/iwlegacy/4965-mac.c
+++ b/drivers/net/wireless/iwlegacy/4965-mac.c
@@ -5711,7 +5711,7 @@ il4965_mac_setup_register(struct il_priv *il, u32 max_probe_length)
         /* Tell mac80211 our characteristics */
         hw->flags =
             IEEE80211_HW_SIGNAL_DBM | IEEE80211_HW_AMPDU_AGGREGATION |
-            IEEE80211_HW_NEED_DTIM_PERIOD | IEEE80211_HW_SPECTRUM_MGMT |
+            IEEE80211_HW_NEED_DTIM_BEFORE_ASSOC | IEEE80211_HW_SPECTRUM_MGMT |
             IEEE80211_HW_REPORTS_TX_ACK_STATUS | IEEE80211_HW_SUPPORTS_PS |
             IEEE80211_HW_SUPPORTS_DYNAMIC_PS;
         if (il->cfg->sku & IL_SKU_N)
diff --git a/drivers/net/wireless/iwlwifi/dvm/mac80211.c b/drivers/net/wireless/iwlwifi/dvm/mac80211.c
index fa43c0d6abe2..8e5c5c5ce06f 100644
--- a/drivers/net/wireless/iwlwifi/dvm/mac80211.c
+++ b/drivers/net/wireless/iwlwifi/dvm/mac80211.c
@@ -145,7 +145,7 @@ int iwlagn_mac_setup_register(struct iwl_priv *priv,
         /* Tell mac80211 our characteristics */
         hw->flags = IEEE80211_HW_SIGNAL_DBM |
                     IEEE80211_HW_AMPDU_AGGREGATION |
-                    IEEE80211_HW_NEED_DTIM_PERIOD |
+                    IEEE80211_HW_NEED_DTIM_BEFORE_ASSOC |
                     IEEE80211_HW_SPECTRUM_MGMT |
                     IEEE80211_HW_REPORTS_TX_ACK_STATUS |
                     IEEE80211_HW_QUEUE_CONTROL |
diff --git a/include/net/mac80211.h b/include/net/mac80211.h
index 7a27e00c513a..398b6ca4a9c5 100644
--- a/include/net/mac80211.h
+++ b/include/net/mac80211.h
@@ -208,6 +208,8 @@ struct ieee80211_chanctx_conf {
  * @BSS_CHANGED_TXPOWER: TX power setting changed for this interface
  * @BSS_CHANGED_P2P_PS: P2P powersave settings (CTWindow, opportunistic PS)
  *      changed (currently only in P2P client mode, GO mode will be later)
+ * @BSS_CHANGED_DTIM_PERIOD: the DTIM period value was changed (set when
+ *      it becomes valid, managed mode only)
  */
 enum ieee80211_bss_change {
         BSS_CHANGED_ASSOC               = 1<<0,
@@ -230,6 +232,7 @@ enum ieee80211_bss_change {
         BSS_CHANGED_PS                  = 1<<17,
         BSS_CHANGED_TXPOWER             = 1<<18,
         BSS_CHANGED_P2P_PS              = 1<<19,
+        BSS_CHANGED_DTIM_PERIOD         = 1<<20,
 
         /* when adding here, make sure to change ieee80211_reconfig */
 };
@@ -271,9 +274,8 @@ enum ieee80211_rssi_event {
  *      if the hardware cannot handle this it must set the
  *      IEEE80211_HW_2GHZ_SHORT_SLOT_INCAPABLE hardware flag
  * @dtim_period: num of beacons before the next DTIM, for beaconing,
- *      valid in station mode only while @assoc is true and if also
- *      requested by %IEEE80211_HW_NEED_DTIM_PERIOD (cf. also hw conf
- *      @ps_dtim_period)
+ *      valid in station mode only if after the driver was notified
+ *      with the %BSS_CHANGED_DTIM_PERIOD flag, will be non-zero then.
  * @sync_tsf: last beacon's/probe response's TSF timestamp (could be old
  *      as it may have been received during scanning long ago)
  * @sync_device_ts: the device timestamp corresponding to the sync_tsf,
@@ -1328,9 +1330,9 @@ struct ieee80211_tx_control {
  *      When this flag is set, signaling beacon-loss will cause an immediate
  *      change to disassociated state.
  *
- * @IEEE80211_HW_NEED_DTIM_PERIOD:
- *      This device needs to know the DTIM period for the BSS before
- *      associating.
+ * @IEEE80211_HW_NEED_DTIM_BEFORE_ASSOC:
+ *      This device needs to get data from beacon before association (i.e.
+ *      dtim_period).
  *
  * @IEEE80211_HW_SUPPORTS_PER_STA_GTK: The device's crypto engine supports
  *      per-station GTKs as used by IBSS RSN or during fast transition. If
@@ -1375,7 +1377,7 @@ enum ieee80211_hw_flags {
         IEEE80211_HW_2GHZ_SHORT_PREAMBLE_INCAPABLE      = 1<<4,
         IEEE80211_HW_SIGNAL_UNSPEC                      = 1<<5,
         IEEE80211_HW_SIGNAL_DBM                         = 1<<6,
-        IEEE80211_HW_NEED_DTIM_PERIOD                   = 1<<7,
+        IEEE80211_HW_NEED_DTIM_BEFORE_ASSOC             = 1<<7,
         IEEE80211_HW_SPECTRUM_MGMT                      = 1<<8,
         IEEE80211_HW_AMPDU_AGGREGATION                  = 1<<9,
         IEEE80211_HW_SUPPORTS_PS                        = 1<<10,
diff --git a/net/mac80211/debugfs.c b/net/mac80211/debugfs.c
index 466f4b45dd94..8e6040998ba6 100644
--- a/net/mac80211/debugfs.c
+++ b/net/mac80211/debugfs.c
@@ -121,8 +121,8 @@ static ssize_t hwflags_read(struct file *file, char __user *user_buf,
                 sf += snprintf(buf + sf, mxln - sf, "SIGNAL_UNSPEC\n");
         if (local->hw.flags & IEEE80211_HW_SIGNAL_DBM)
                 sf += snprintf(buf + sf, mxln - sf, "SIGNAL_DBM\n");
-        if (local->hw.flags & IEEE80211_HW_NEED_DTIM_PERIOD)
-                sf += snprintf(buf + sf, mxln - sf, "NEED_DTIM_PERIOD\n");
+        if (local->hw.flags & IEEE80211_HW_NEED_DTIM_BEFORE_ASSOC)
+                sf += snprintf(buf + sf, mxln - sf, "NEED_DTIM_BEFORE_ASSOC\n");
         if (local->hw.flags & IEEE80211_HW_SPECTRUM_MGMT)
                 sf += snprintf(buf + sf, mxln - sf, "SPECTRUM_MGMT\n");
         if (local->hw.flags & IEEE80211_HW_AMPDU_AGGREGATION)
diff --git a/net/mac80211/ieee80211_i.h b/net/mac80211/ieee80211_i.h
index 2f50be7eea09..5ce0b6b6e182 100644
--- a/net/mac80211/ieee80211_i.h
+++ b/net/mac80211/ieee80211_i.h
@@ -399,7 +399,7 @@ struct ieee80211_mgd_assoc_data {
         u8 ssid_len;
         u8 supp_rates_len;
         bool wmm, uapsd;
-        bool have_beacon;
+        bool have_beacon, need_beacon;
         bool synced;
 
         u8 ap_ht_param;
diff --git a/net/mac80211/mlme.c b/net/mac80211/mlme.c
index d79b9cd72fc5..a5dba67bbe0b 100644
--- a/net/mac80211/mlme.c
+++ b/net/mac80211/mlme.c
@@ -1445,7 +1445,7 @@ static void ieee80211_set_associated(struct ieee80211_sub_if_data *sdata,
 
         ieee80211_led_assoc(local, 1);
 
-        if (local->hw.flags & IEEE80211_HW_NEED_DTIM_PERIOD) {
+        if (sdata->u.mgd.assoc_data->have_beacon) {
                 /*
                  * If the AP is buggy we may get here with no DTIM period
                  * known, so assume it's 1 which is the only safe assumption
@@ -1453,6 +1453,7 @@ static void ieee80211_set_associated(struct ieee80211_sub_if_data *sdata,
                  * probably just won't work at all.
                  */
                 bss_conf->dtim_period = sdata->u.mgd.dtim_period ?: 1;
+                bss_info_changed |= BSS_CHANGED_DTIM_PERIOD;
         } else {
                 bss_conf->dtim_period = 0;
         }
@@ -2548,13 +2549,14 @@ static void ieee80211_rx_mgmt_beacon(struct ieee80211_sub_if_data *sdata,
         chan = chanctx_conf->def.chan;
         rcu_read_unlock();
 
-        if (ifmgd->assoc_data && !ifmgd->assoc_data->have_beacon &&
+        if (ifmgd->assoc_data && ifmgd->assoc_data->need_beacon &&
             ether_addr_equal(mgmt->bssid, ifmgd->assoc_data->bss->bssid)) {
                 ieee802_11_parse_elems(mgmt->u.beacon.variable,
                                        len - baselen, &elems);
 
                 ieee80211_rx_bss_info(sdata, mgmt, len, rx_status, &elems);
                 ifmgd->assoc_data->have_beacon = true;
+                ifmgd->assoc_data->need_beacon = false;
                 /* continue assoc process */
                 ifmgd->assoc_data->timeout = jiffies;
                 run_again(ifmgd, ifmgd->assoc_data->timeout);
@@ -2711,6 +2713,19 @@ static void ieee80211_rx_mgmt_beacon(struct ieee80211_sub_if_data *sdata,
                                      elems.wmm_param_len))
                 changed |= BSS_CHANGED_QOS;
 
+        /*
+         * If we haven't had a beacon before, tell the driver about the
+         * DTIM period now.
+         */
+        if (!bss_conf->dtim_period) {
+                /* a few bogus AP send dtim_period = 0 or no TIM IE */
+                if (elems.tim)
+                        bss_conf->dtim_period = elems.tim->dtim_period ?: 1;
+                else
+                        bss_conf->dtim_period = 1;
+                changed |= BSS_CHANGED_DTIM_PERIOD;
+        }
+
         if (elems.erp_info && elems.erp_info_len >= 1) {
                 erp_valid = true;
                 erp_value = elems.erp_info[0];
@@ -2989,7 +3004,8 @@ void ieee80211_sta_work(struct ieee80211_sub_if_data *sdata)
 
         if (ifmgd->assoc_data &&
             time_after(jiffies, ifmgd->assoc_data->timeout)) {
-                if (!ifmgd->assoc_data->have_beacon ||
+                if ((ifmgd->assoc_data->need_beacon &&
+                     !ifmgd->assoc_data->have_beacon) ||
                     ieee80211_do_assoc(sdata)) {
                         u8 bssid[ETH_ALEN];
 
@@ -3776,6 +3792,7 @@ int ieee80211_mgd_assoc(struct ieee80211_sub_if_data *sdata,
         struct ieee80211_if_managed *ifmgd = &sdata->u.mgd;
         struct ieee80211_bss *bss = (void *)req->bss->priv;
         struct ieee80211_mgd_assoc_data *assoc_data;
+        const struct cfg80211_bss_ies *beacon_ies;
         struct ieee80211_supported_band *sband;
         const u8 *ssidie, *ht_ie, *vht_ie;
         int i, err;
@@ -3941,38 +3958,35 @@ int ieee80211_mgd_assoc(struct ieee80211_sub_if_data *sdata,
         if (err)
                 goto err_clear;
 
-        if (sdata->local->hw.flags & IEEE80211_HW_NEED_DTIM_PERIOD) {
-                const struct cfg80211_bss_ies *beacon_ies;
+        rcu_read_lock();
+        beacon_ies = rcu_dereference(req->bss->beacon_ies);
 
-                rcu_read_lock();
-                beacon_ies = rcu_dereference(req->bss->beacon_ies);
-                if (!beacon_ies) {
-                        /*
-                         * Wait up to one beacon interval ...
-                         * should this be more if we miss one?
-                         */
-                        sdata_info(sdata, "waiting for beacon from %pM\n",
-                                   ifmgd->bssid);
-                        assoc_data->timeout =
-                                TU_TO_EXP_TIME(req->bss->beacon_interval);
-                } else {
-                        const u8 *tim_ie = cfg80211_find_ie(WLAN_EID_TIM,
-                                                            beacon_ies->data,
-                                                            beacon_ies->len);
-                        if (tim_ie && tim_ie[1] >=
-                                        sizeof(struct ieee80211_tim_ie)) {
-                                const struct ieee80211_tim_ie *tim;
-                                tim = (void *)(tim_ie + 2);
-                                ifmgd->dtim_period = tim->dtim_period;
-                        }
-                        assoc_data->have_beacon = true;
-                        assoc_data->timeout = jiffies;
+        if (sdata->local->hw.flags & IEEE80211_HW_NEED_DTIM_BEFORE_ASSOC &&
+            !beacon_ies) {
+                /*
+                 * Wait up to one beacon interval ...
+                 * should this be more if we miss one?
+                 */
+                sdata_info(sdata, "waiting for beacon from %pM\n",
+                           ifmgd->bssid);
+                assoc_data->timeout = TU_TO_EXP_TIME(req->bss->beacon_interval);
+                assoc_data->need_beacon = true;
+        } else if (beacon_ies) {
+                const u8 *tim_ie = cfg80211_find_ie(WLAN_EID_TIM,
+                                                    beacon_ies->data,
+                                                    beacon_ies->len);
+                if (tim_ie && tim_ie[1] >= sizeof(struct ieee80211_tim_ie)) {
+                        const struct ieee80211_tim_ie *tim;
+                        tim = (void *)(tim_ie + 2);
+                        ifmgd->dtim_period = tim->dtim_period;
                 }
-                rcu_read_unlock();
-        } else {
                 assoc_data->have_beacon = true;
                 assoc_data->timeout = jiffies;
+        } else {
+                assoc_data->timeout = jiffies;
         }
+        rcu_read_unlock();
+
         run_again(ifmgd, assoc_data->timeout);
 
         if (bss->corrupt_data) {
diff --git a/net/mac80211/util.c b/net/mac80211/util.c
index 7519018ff71a..1c74512697f0 100644
--- a/net/mac80211/util.c
+++ b/net/mac80211/util.c
@@ -1538,6 +1538,10 @@ int ieee80211_reconfig(struct ieee80211_local *local)
                         changed |= BSS_CHANGED_ASSOC |
                                    BSS_CHANGED_ARP_FILTER |
                                    BSS_CHANGED_PS;
+
+                        if (sdata->u.mgd.dtim_period)
+                                changed |= BSS_CHANGED_DTIM_PERIOD;
+
                         mutex_lock(&sdata->u.mgd.mtx);
                         ieee80211_bss_info_change_notify(sdata, changed);
                         mutex_unlock(&sdata->u.mgd.mtx);