diff --git a/drivers/net/wireless/ath/carl9170/main.c b/drivers/net/wireless/ath/carl9170/main.c
index ef82751722e0bd4ae45c50ad18e705cee755222d..f293b3ff475628a389c1337df81d24cb3b3b5640 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 f1dc040065646c5ec9d15068a084ff22d00eb656..d3cc776d2d34c0cf8e4824339f62da8e08b21957 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 fa43c0d6abe295aa96428c4b27e3c6d1737542c1..8e5c5c5ce06fdd0fbef9c5a5cb0e233810cd807b 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 7a27e00c513ac4afe82c7f090170ce89bb585925..398b6ca4a9c558d449a38d0c4bfacdcaaff3bc61 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 466f4b45dd94fdf72517d60a5a71e5ba8bbc9daf..8e6040998ba6e43b1eaabeb430bbec93239418b4 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 2f50be7eea09d03929599c50cafa08147b7877d5..5ce0b6b6e1824babdfe63321c2e17b0554d495ee 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 d79b9cd72fc5fbe20df062752dc4ebb5e5153227..a5dba67bbe0b431eb0efce617bd4004b4d45b3cc 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 7519018ff71af2844241f43697a1926f54122def..1c74512697f0590d3772733b1730d1d9888d804a 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);