mac80211: introduce hw config change flags

This makes mac80211 notify the driver which configuration
actually changed, e.g. channel etc.

No driver changes, this is just plumbing, driver authors are
expected to act on this if they want to.

Also remove the HW CONFIG debug printk, it's incorrect, often
we configure something else.

Signed-off-by: Johannes Berg <johannes@sipsolutions.net>
Signed-off-by: John W. Linville <linville@tuxdriver.com>

7 files changed, 56 insertions, 32 deletions

diff --git a/net/mac80211/cfg.c b/net/mac80211/cfg.c
index a5dea61..8ea3090 100644
--- a/net/mac80211/cfg.c
+++ b/net/mac80211/cfg.c
@@ -394,7 +394,8 @@ static int ieee80211_config_beacon(struct ieee80211_sub_if_data *sdata,
 	 */
 	if (params->interval) {
 		sdata->local->hw.conf.beacon_int = params->interval;
-		ieee80211_hw_config(sdata->local);
+		ieee80211_hw_config(sdata->local,
+				    IEEE80211_CONF_CHANGE_BEACON_INTERVAL);
 		/*
 		 * We updated some parameter so if below bails out
 		 * it's not an error.
diff --git a/net/mac80211/ieee80211_i.h b/net/mac80211/ieee80211_i.h
index 8801583..1deb787 100644
--- a/net/mac80211/ieee80211_i.h
+++ b/net/mac80211/ieee80211_i.h
@@ -875,7 +875,7 @@ static inline int ieee80211_bssid_match(const u8 *raddr, const u8 *addr)
 }
 
 
-int ieee80211_hw_config(struct ieee80211_local *local);
+int ieee80211_hw_config(struct ieee80211_local *local, u32 changed);
 int ieee80211_if_config(struct ieee80211_sub_if_data *sdata, u32 changed);
 void ieee80211_tx_set_protected(struct ieee80211_tx_data *tx);
 void ieee80211_bss_info_change_notify(struct ieee80211_sub_if_data *sdata,
diff --git a/net/mac80211/iface.c b/net/mac80211/iface.c
index 8336fee..df28c5f 100644
--- a/net/mac80211/iface.c
+++ b/net/mac80211/iface.c
@@ -65,7 +65,7 @@ static int ieee80211_open(struct net_device *dev)
 	struct ieee80211_if_init_conf conf;
 	u32 changed = 0;
 	int res;
-	bool need_hw_reconfig = 0;
+	u32 hw_reconf_flags = 0;
 	u8 null_addr[ETH_ALEN] = {0};
 
 	/* fail early if user set an invalid address */
@@ -152,7 +152,8 @@ static int ieee80211_open(struct net_device *dev)
 			res = local->ops->start(local_to_hw(local));
 		if (res)
 			goto err_del_bss;
-		need_hw_reconfig = 1;
+		/* we're brought up, everything changes */
+		hw_reconf_flags = ~0;
 		ieee80211_led_radio(local, local->hw.conf.radio_enabled);
 	}
 
@@ -198,8 +199,10 @@ static int ieee80211_open(struct net_device *dev)
 
 		/* must be before the call to ieee80211_configure_filter */
 		local->monitors++;
-		if (local->monitors == 1)
+		if (local->monitors == 1) {
 			local->hw.conf.flags |= IEEE80211_CONF_RADIOTAP;
+			hw_reconf_flags |= IEEE80211_CONF_CHANGE_RADIOTAP;
+		}
 
 		if (sdata->u.mntr_flags & MONITOR_FLAG_FCSFAIL)
 			local->fif_fcsfail++;
@@ -279,8 +282,8 @@ static int ieee80211_open(struct net_device *dev)
 		atomic_inc(&local->iff_promiscs);
 
 	local->open_count++;
-	if (need_hw_reconfig) {
-		ieee80211_hw_config(local);
+	if (hw_reconf_flags) {
+		ieee80211_hw_config(local, hw_reconf_flags);
 		/*
 		 * set default queue parameters so drivers don't
 		 * need to initialise the hardware if the hardware
@@ -322,6 +325,7 @@ static int ieee80211_stop(struct net_device *dev)
 	struct ieee80211_local *local = sdata->local;
 	struct ieee80211_if_init_conf conf;
 	struct sta_info *sta;
+	u32 hw_reconf_flags = 0;
 
 	/*
 	 * Stop TX on this interface first.
@@ -405,8 +409,10 @@ static int ieee80211_stop(struct net_device *dev)
 		}
 
 		local->monitors--;
-		if (local->monitors == 0)
+		if (local->monitors == 0) {
 			local->hw.conf.flags &= ~IEEE80211_CONF_RADIOTAP;
+			hw_reconf_flags |= IEEE80211_CONF_CHANGE_RADIOTAP;
+		}
 
 		if (sdata->u.mntr_flags & MONITOR_FLAG_FCSFAIL)
 			local->fif_fcsfail--;
@@ -504,8 +510,15 @@ static int ieee80211_stop(struct net_device *dev)
 
 		tasklet_disable(&local->tx_pending_tasklet);
 		tasklet_disable(&local->tasklet);
+
+		/* no reconfiguring after stop! */
+		hw_reconf_flags = 0;
 	}
 
+	/* do after stop to avoid reconfiguring when we stop anyway */
+	if (hw_reconf_flags)
+		ieee80211_hw_config(local, hw_reconf_flags);
+
 	return 0;
 }
 
diff --git a/net/mac80211/main.c b/net/mac80211/main.c
index 07f8127..c936017 100644
--- a/net/mac80211/main.c
+++ b/net/mac80211/main.c
@@ -197,31 +197,34 @@ int ieee80211_if_config(struct ieee80211_sub_if_data *sdata, u32 changed)
 					    &sdata->vif, &conf);
 }
 
-int ieee80211_hw_config(struct ieee80211_local *local)
+int ieee80211_hw_config(struct ieee80211_local *local, u32 changed)
 {
 	struct ieee80211_channel *chan;
 	int ret = 0;
+	int power;
 
 	if (local->sw_scanning)
 		chan = local->scan_channel;
 	else
 		chan = local->oper_channel;
 
-	local->hw.conf.channel = chan;
+	if (chan != local->hw.conf.channel) {
+		local->hw.conf.channel = chan;
+		changed |= IEEE80211_CONF_CHANGE_CHANNEL;
+	}
+
 
 	if (!local->hw.conf.power_level)
-		local->hw.conf.power_level = chan->max_power;
+		power = chan->max_power;
 	else
-		local->hw.conf.power_level = min(chan->max_power,
-					       local->hw.conf.power_level);
-
-#ifdef CONFIG_MAC80211_VERBOSE_DEBUG
-	printk(KERN_DEBUG "%s: HW CONFIG: freq=%d\n",
-	       wiphy_name(local->hw.wiphy), chan->center_freq);
-#endif
+		power = min(chan->max_power, local->hw.conf.power_level);
+	if (local->hw.conf.power_level != power) {
+		changed |= IEEE80211_CONF_CHANGE_POWER;
+		local->hw.conf.power_level = power;
+	}
 
-	if (local->open_count) {
-		ret = local->ops->config(local_to_hw(local), &local->hw.conf);
+	if (changed && local->open_count) {
+		ret = local->ops->config(local_to_hw(local), changed);
 		/*
 		 * HW reconfiguration should never fail, the driver has told
 		 * us what it can support so it should live up to that promise.
@@ -672,7 +675,7 @@ struct ieee80211_hw *ieee80211_alloc_hw(size_t priv_data_len,
 	local->fragmentation_threshold = IEEE80211_MAX_FRAG_THRESHOLD;
 	local->short_retry_limit = 7;
 	local->long_retry_limit = 4;
-	local->hw.conf.radio_enabled = 1;
+	local->hw.conf.radio_enabled = true;
 
 	INIT_LIST_HEAD(&local->interfaces);
 
diff --git a/net/mac80211/scan.c b/net/mac80211/scan.c
index 0989b1c..7372d7a 100644
--- a/net/mac80211/scan.c
+++ b/net/mac80211/scan.c
@@ -448,12 +448,17 @@ void ieee80211_scan_completed(struct ieee80211_hw *hw)
 
 	if (local->hw_scanning) {
 		local->hw_scanning = false;
-		ieee80211_hw_config(local);
+		/*
+		 * Somebody might have requested channel change during scan
+		 * that we won't have acted upon, try now. ieee80211_hw_config
+		 * will set the flag based on actual changes.
+		 */
+		ieee80211_hw_config(local, 0);
 		goto done;
 	}
 
 	local->sw_scanning = false;
-	ieee80211_hw_config(local);
+	ieee80211_hw_config(local, IEEE80211_CONF_CHANGE_CHANNEL);
 
 	netif_tx_lock_bh(local->mdev);
 	netif_addr_lock(local->mdev);
@@ -540,7 +545,8 @@ void ieee80211_scan_work(struct work_struct *work)
 
 		if (!skip) {
 			local->scan_channel = chan;
-			if (ieee80211_hw_config(local))
+			if (ieee80211_hw_config(local,
+						IEEE80211_CONF_CHANGE_CHANNEL))
 				skip = 1;
 		}
 
diff --git a/net/mac80211/util.c b/net/mac80211/util.c
index 9941a60..3288c3d 100644
--- a/net/mac80211/util.c
+++ b/net/mac80211/util.c
@@ -645,7 +645,8 @@ int ieee80211_set_freq(struct ieee80211_sub_if_data *sdata, int freqMHz)
 		if (local->sw_scanning || local->hw_scanning)
 			ret = 0;
 		else
-			ret = ieee80211_hw_config(local);
+			ret = ieee80211_hw_config(
+				local, IEEE80211_CONF_CHANGE_CHANNEL);
 
 		rate_control_clear(local);
 	}
diff --git a/net/mac80211/wext.c b/net/mac80211/wext.c
index a3af151..94c4b35 100644
--- a/net/mac80211/wext.c
+++ b/net/mac80211/wext.c
@@ -656,7 +656,7 @@ static int ieee80211_ioctl_siwtxpower(struct net_device *dev,
 				      union iwreq_data *data, char *extra)
 {
 	struct ieee80211_local *local = wdev_priv(dev->ieee80211_ptr);
-	bool need_reconfig = 0;
+	u32 reconf_flags = 0;
 	int new_power_level;
 
 	if ((data->txpower.flags & IW_TXPOW_TYPE) != IW_TXPOW_DBM)
@@ -680,17 +680,17 @@ static int ieee80211_ioctl_siwtxpower(struct net_device *dev,
 
 	if (local->hw.conf.power_level != new_power_level) {
 		local->hw.conf.power_level = new_power_level;
-		need_reconfig = 1;
+		reconf_flags |= IEEE80211_CONF_CHANGE_POWER;
 	}
 
 	if (local->hw.conf.radio_enabled != !(data->txpower.disabled)) {
 		local->hw.conf.radio_enabled = !(data->txpower.disabled);
-		need_reconfig = 1;
+		reconf_flags |= IEEE80211_CONF_CHANGE_RADIO_ENABLED;
 		ieee80211_led_radio(local, local->hw.conf.radio_enabled);
 	}
 
-	if (need_reconfig)
-		ieee80211_hw_config(local);
+	if (reconf_flags)
+		ieee80211_hw_config(local, reconf_flags);
 
 	return 0;
 }
@@ -976,7 +976,7 @@ static int ieee80211_ioctl_siwpower(struct net_device *dev,
 
 	if (wrq->disabled) {
 		conf->flags &= ~IEEE80211_CONF_PS;
-		return ieee80211_hw_config(local);
+		return ieee80211_hw_config(local, IEEE80211_CONF_CHANGE_PS);
 	}
 
 	switch (wrq->flags & IW_POWER_MODE) {
@@ -989,7 +989,7 @@ static int ieee80211_ioctl_siwpower(struct net_device *dev,
 		return -EINVAL;
 	}
 
-	return ieee80211_hw_config(local);
+	return ieee80211_hw_config(local, IEEE80211_CONF_CHANGE_PS);
 }
 
 static int ieee80211_ioctl_giwpower(struct net_device *dev,