b43: Fix some MAC locking

This fixes some locking w.r.t. the lower MAC (firmware).
It also removes a lot of ancient IRQ-locking that's not needed anymore.
We simply suspend the MAC. That's easier and causes less trouble.
Signed-off-by: Michael Buesch <mb@bu3sch.de>
Signed-off-by: John W. Linville <linville@tuxdriver.com>

drivers/net/wireless/b43/main.c

@@ -3324,7 +3324,6 @@ static int b43_op_config(struct ieee80211_hw *hw, u32 changed)
 	unsigned long flags;
 	int antenna;
 	int err = 0;
-	u32 savedirqs;
 
 	mutex_lock(&wl->mutex);
 
@@ -3335,24 +3334,14 @@ static int b43_op_config(struct ieee80211_hw *hw, u32 changed)
 	dev = wl->current_dev;
 	phy = &dev->phy;
 
+	b43_mac_suspend(dev);
+
 	if (changed & IEEE80211_CONF_CHANGE_RETRY_LIMITS)
 		b43_set_retry_limits(dev, conf->short_frame_max_tx_count,
 					  conf->long_frame_max_tx_count);
 	changed &= ~IEEE80211_CONF_CHANGE_RETRY_LIMITS;
 	if (!changed)
-		goto out_unlock_mutex;
-
-	/* Disable IRQs while reconfiguring the device.
-	 * This makes it possible to drop the spinlock throughout
-	 * the reconfiguration process. */
-	spin_lock_irqsave(&wl->irq_lock, flags);
-	if (b43_status(dev) < B43_STAT_STARTED) {
-		spin_unlock_irqrestore(&wl->irq_lock, flags);
-		goto out_unlock_mutex;
-	}
-	savedirqs = b43_interrupt_disable(dev, B43_IRQ_ALL);
-	spin_unlock_irqrestore(&wl->irq_lock, flags);
-	b43_synchronize_irq(dev);
+		goto out_mac_enable;
 
 	/* Switch to the requested channel.
 	 * The firmware takes care of races with the TX handler. */
@@ -3399,11 +3388,9 @@ static int b43_op_config(struct ieee80211_hw *hw, u32 changed)
 		}
 	}
 
-	spin_lock_irqsave(&wl->irq_lock, flags);
-	b43_interrupt_enable(dev, savedirqs);
-	mmiowb();
-	spin_unlock_irqrestore(&wl->irq_lock, flags);
-      out_unlock_mutex:
+out_mac_enable:
+	b43_mac_enable(dev);
+out_unlock_mutex:
 	mutex_unlock(&wl->mutex);
 
 	return err;
@@ -3461,27 +3448,12 @@ static void b43_op_bss_info_changed(struct ieee80211_hw *hw,
 {
 	struct b43_wl *wl = hw_to_b43_wl(hw);
 	struct b43_wldev *dev;
-	struct b43_phy *phy;
-	unsigned long flags;
-	u32 savedirqs;
 
 	mutex_lock(&wl->mutex);
 
 	dev = wl->current_dev;
-	phy = &dev->phy;
-
-	/* Disable IRQs while reconfiguring the device.
-	 * This makes it possible to drop the spinlock throughout
-	 * the reconfiguration process. */
-	spin_lock_irqsave(&wl->irq_lock, flags);
-	if (b43_status(dev) < B43_STAT_STARTED) {
-		spin_unlock_irqrestore(&wl->irq_lock, flags);
+	if (!dev || b43_status(dev) < B43_STAT_STARTED)
 		goto out_unlock_mutex;
-	}
-	savedirqs = b43_interrupt_disable(dev, B43_IRQ_ALL);
-	spin_unlock_irqrestore(&wl->irq_lock, flags);
-	b43_synchronize_irq(dev);
-
 	b43_mac_suspend(dev);
 
 	if (changed & BSS_CHANGED_BASIC_RATES)
@@ -3495,13 +3467,7 @@ static void b43_op_bss_info_changed(struct ieee80211_hw *hw,
 	}
 
 	b43_mac_enable(dev);
-
-	spin_lock_irqsave(&wl->irq_lock, flags);
-	b43_interrupt_enable(dev, savedirqs);
-	/* XXX: why? */
-	mmiowb();
-	spin_unlock_irqrestore(&wl->irq_lock, flags);
- out_unlock_mutex:
+out_unlock_mutex:
 	mutex_unlock(&wl->mutex);
 
 	return;

drivers/net/wireless/b43/phy_common.c

@@ -178,13 +178,27 @@ void b43_phy_unlock(struct b43_wldev *dev)
 		b43_power_saving_ctl_bits(dev, 0);
 }
 
+static inline void assert_mac_suspended(struct b43_wldev *dev)
+{
+	if (!B43_DEBUG)
+		return;
+	if ((b43_status(dev) >= B43_STAT_INITIALIZED) &&
+	    (dev->mac_suspended <= 0)) {
+		b43dbg(dev->wl, "PHY/RADIO register access with "
+		       "enabled MAC.\n");
+		dump_stack();
+	}
+}
+
 u16 b43_radio_read(struct b43_wldev *dev, u16 reg)
 {
+	assert_mac_suspended(dev);
 	return dev->phy.ops->radio_read(dev, reg);
 }
 
 void b43_radio_write(struct b43_wldev *dev, u16 reg, u16 value)
 {
+	assert_mac_suspended(dev);
 	dev->phy.ops->radio_write(dev, reg, value);
 }
 
@@ -208,11 +222,13 @@ void b43_radio_maskset(struct b43_wldev *dev, u16 offset, u16 mask, u16 set)
 
 u16 b43_phy_read(struct b43_wldev *dev, u16 reg)
 {
+	assert_mac_suspended(dev);
 	return dev->phy.ops->phy_read(dev, reg);
 }
 
 void b43_phy_write(struct b43_wldev *dev, u16 reg, u16 value)
 {
+	assert_mac_suspended(dev);
 	dev->phy.ops->phy_write(dev, reg, value);
 }
 

drivers/net/wireless/b43/phy_g.c

@@ -3047,6 +3047,8 @@ static void b43_gphy_op_adjust_txpower(struct b43_wldev *dev)
 	int rfatt, bbatt;
 	u8 tx_control;
 
+	b43_mac_suspend(dev);
+
 	spin_lock_irq(&dev->wl->irq_lock);
 
 	/* Calculate the new attenuation values. */
@@ -3103,6 +3105,8 @@ static void b43_gphy_op_adjust_txpower(struct b43_wldev *dev)
 			  gphy->tx_control);
 	b43_radio_unlock(dev);
 	b43_phy_unlock(dev);
+
+	b43_mac_enable(dev);
 }
 
 static enum b43_txpwr_result b43_gphy_op_recalc_txpower(struct b43_wldev *dev,
@@ -3215,9 +3219,9 @@ static void b43_gphy_op_pwork_15sec(struct b43_wldev *dev)
 	struct b43_phy *phy = &dev->phy;
 	struct b43_phy_g *gphy = phy->g;
 
+	b43_mac_suspend(dev);
 	//TODO: update_aci_moving_average
 	if (gphy->aci_enable && gphy->aci_wlan_automatic) {
-		b43_mac_suspend(dev);
 		if (!gphy->aci_enable && 1 /*TODO: not scanning? */ ) {
 			if (0 /*TODO: bunch of conditions */ ) {
 				phy->ops->interf_mitigation(dev,
@@ -3227,12 +3231,12 @@ static void b43_gphy_op_pwork_15sec(struct b43_wldev *dev)
 			   if (/*(aci_average > 1000) &&*/ !b43_gphy_aci_scan(dev))
 				phy->ops->interf_mitigation(dev, B43_INTERFMODE_NONE);
 		}
-		b43_mac_enable(dev);
 	} else if (gphy->interfmode == B43_INTERFMODE_NONWLAN &&
 		   phy->rev == 1) {
 		//TODO: implement rev1 workaround
 	}
 	b43_lo_g_maintanance_work(dev);
+	b43_mac_enable(dev);
 }
 
 static void b43_gphy_op_pwork_60sec(struct b43_wldev *dev)