[PATCH 1/7] rt2x00: Remove usage of deprecated radio_enabled & IEEE80211_CONF_CHANGE_RADIO_ENABLED

[PATCH 1/7] rt2x00: Remove usage of deprecated radio_enabled & IEEE80211_CONF_CHANGE_RADIO_ENABLED

[Ivo van Doorn]

In the config() callback function the fields radio_enabled and
the change flag IEEE80211_CONF_CHANGE_RADIO_ENABLED have been
deprecated. This removes the usage of those fields by improving
antenna change detection in the antenna configuration function.

Signed-off-by: Ivo van Doorn <IvDoorn@gmail.com>
---
 drivers/net/wireless/rt2x00/rt2x00config.c |   22 ++++++++---
 drivers/net/wireless/rt2x00/rt2x00dev.c    |    7 ++++
 drivers/net/wireless/rt2x00/rt2x00link.c   |   12 ++++--
 drivers/net/wireless/rt2x00/rt2x00mac.c    |   54 ++++++++++------------------
 4 files changed, 50 insertions(+), 45 deletions(-)

diff --git a/drivers/net/wireless/rt2x00/rt2x00config.c b/drivers/net/wireless/rt2x00/rt2x00config.c
index 3845316..3501788 100644
--- a/drivers/net/wireless/rt2x00/rt2x00config.c
+++ b/drivers/net/wireless/rt2x00/rt2x00config.c
@@ -124,8 +124,9 @@ enum antenna rt2x00lib_config_antenna_check(enum antenna current_ant,
 }
 
 void rt2x00lib_config_antenna(struct rt2x00_dev *rt2x00dev,
-			      struct antenna_setup ant)
+			      struct antenna_setup config)
 {
+	struct link_ant *ant = &rt2x00dev->link.ant;
 	struct antenna_setup *def = &rt2x00dev->default_ant;
 	struct antenna_setup *active = &rt2x00dev->link.ant.active;
 
@@ -134,14 +135,23 @@ void rt2x00lib_config_antenna(struct rt2x00_dev *rt2x00dev,
 	 * ANTENNA_SW_DIVERSITY state to the driver.
 	 * If that happens, fallback to hardware defaults,
 	 * or our own default.
+	 * If diversity handling is active for a particular antenna,
+	 * we shouldn't overwrite that antenna.
 	 * The calls to rt2x00lib_config_antenna_check()
 	 * might have caused that we restore back to the already
 	 * active setting. If that has happened we can quit.
 	 */
-	ant.rx = rt2x00lib_config_antenna_check(ant.rx, def->rx);
-	ant.tx = rt2x00lib_config_antenna_check(ant.tx, def->tx);
+	if (!(ant->flags & ANTENNA_RX_DIVERSITY))
+		config.rx = rt2x00lib_config_antenna_check(config.rx, def->rx);
+	else
+		config.rx = active->rx;
 
-	if (ant.rx == active->rx && ant.tx == active->tx)
+	if (!(ant->flags & ANTENNA_TX_DIVERSITY))
+		config.tx = rt2x00lib_config_antenna_check(config.tx, def->tx);
+	else
+		config.tx = active->tx;
+
+	if (config.rx == active->rx && config.tx == active->tx)
 		return;
 
 	/*
@@ -156,11 +166,11 @@ void rt2x00lib_config_antenna(struct rt2x00_dev *rt2x00dev,
 	 * The latter is required since we need to recalibrate the
 	 * noise-sensitivity ratio for the new setup.
 	 */
-	rt2x00dev->ops->lib->config_ant(rt2x00dev, &ant);
+	rt2x00dev->ops->lib->config_ant(rt2x00dev, &config);
 
 	rt2x00link_reset_tuner(rt2x00dev, true);
 
-	memcpy(active, &ant, sizeof(ant));
+	memcpy(active, &config, sizeof(config));
 
 	if (test_bit(DEVICE_STATE_ENABLED_RADIO, &rt2x00dev->flags))
 		rt2x00lib_toggle_rx(rt2x00dev, STATE_RADIO_RX_ON_LINK);
diff --git a/drivers/net/wireless/rt2x00/rt2x00dev.c b/drivers/net/wireless/rt2x00/rt2x00dev.c
index db54fcc..e0348cc 100644
--- a/drivers/net/wireless/rt2x00/rt2x00dev.c
+++ b/drivers/net/wireless/rt2x00/rt2x00dev.c
@@ -785,6 +785,13 @@ int rt2x00lib_start(struct rt2x00_dev *rt2x00dev)
 	rt2x00dev->intf_sta_count = 0;
 	rt2x00dev->intf_associated = 0;
 
+	/* Enable the radio */
+	retval = rt2x00lib_enable_radio(rt2x00dev);
+	if (retval) {
+		rt2x00queue_uninitialize(rt2x00dev);
+		return retval;
+	}
+
 	set_bit(DEVICE_STATE_STARTED, &rt2x00dev->flags);
 
 	return 0;
diff --git a/drivers/net/wireless/rt2x00/rt2x00link.c b/drivers/net/wireless/rt2x00/rt2x00link.c
index 9178316..fe951dc 100644
--- a/drivers/net/wireless/rt2x00/rt2x00link.c
+++ b/drivers/net/wireless/rt2x00/rt2x00link.c
@@ -219,6 +219,7 @@ static void rt2x00lib_antenna_diversity_eval(struct rt2x00_dev *rt2x00dev)
 static void rt2x00lib_antenna_diversity(struct rt2x00_dev *rt2x00dev)
 {
 	struct link_ant *ant = &rt2x00dev->link.ant;
+	unsigned int flags = ant->flags;
 
 	/*
 	 * Determine if software diversity is enabled for
@@ -226,13 +227,13 @@ static void rt2x00lib_antenna_diversity(struct rt2x00_dev *rt2x00dev)
 	 * Always perform this check since within the link
 	 * tuner interval the configuration might have changed.
 	 */
-	ant->flags &= ~ANTENNA_RX_DIVERSITY;
-	ant->flags &= ~ANTENNA_TX_DIVERSITY;
+	flags &= ~ANTENNA_RX_DIVERSITY;
+	flags &= ~ANTENNA_TX_DIVERSITY;
 
 	if (rt2x00dev->default_ant.rx == ANTENNA_SW_DIVERSITY)
-		ant->flags |= ANTENNA_RX_DIVERSITY;
+		flags |= ANTENNA_RX_DIVERSITY;
 	if (rt2x00dev->default_ant.tx == ANTENNA_SW_DIVERSITY)
-		ant->flags |= ANTENNA_TX_DIVERSITY;
+		flags |= ANTENNA_TX_DIVERSITY;
 
 	if (!(ant->flags & ANTENNA_RX_DIVERSITY) &&
 	    !(ant->flags & ANTENNA_TX_DIVERSITY)) {
@@ -240,6 +241,9 @@ static void rt2x00lib_antenna_diversity(struct rt2x00_dev *rt2x00dev)
 		return;
 	}
 
+	/* Update flags */
+	ant->flags = flags;
+
 	/*
 	 * If we have only sampled the data over the last period
 	 * we should now harvest the data. Otherwise just evaluate
diff --git a/drivers/net/wireless/rt2x00/rt2x00mac.c b/drivers/net/wireless/rt2x00/rt2x00mac.c
index 81febdf..4164fce 100644
--- a/drivers/net/wireless/rt2x00/rt2x00mac.c
+++ b/drivers/net/wireless/rt2x00/rt2x00mac.c
@@ -338,7 +338,6 @@ int rt2x00mac_config(struct ieee80211_hw *hw, u32 changed)
 {
 	struct rt2x00_dev *rt2x00dev = hw->priv;
 	struct ieee80211_conf *conf = &hw->conf;
-	int status;
 
 	/*
 	 * mac80211 might be calling this function while we are trying
@@ -348,44 +347,29 @@ int rt2x00mac_config(struct ieee80211_hw *hw, u32 changed)
 		return 0;
 
 	/*
-	 * Only change device state when the radio is enabled. It does not
-	 * matter what parameters we have configured when the radio is disabled
-	 * because we won't be able to send or receive anyway. Also note that
-	 * some configuration parameters (e.g. channel and antenna values) can
-	 * only be set when the radio is enabled.
+	 * Some configuration parameters (e.g. channel and antenna values) can
+	 * only be set when the radio is enabled, but do require the RX to
+	 * be off.
 	 */
-	if (conf->radio_enabled) {
-		/* For programming the values, we have to turn RX off */
-		rt2x00lib_toggle_rx(rt2x00dev, STATE_RADIO_RX_OFF);
+	rt2x00lib_toggle_rx(rt2x00dev, STATE_RADIO_RX_OFF);
 
-		/* Enable the radio */
-		status = rt2x00lib_enable_radio(rt2x00dev);
-		if (unlikely(status))
-			return status;
+	/*
+	 * When we've just turned on the radio, we want to reprogram
+	 * everything to ensure a consistent state
+	 */
+	rt2x00lib_config(rt2x00dev, conf, changed);
 
-		/*
-		 * When we've just turned on the radio, we want to reprogram
-		 * everything to ensure a consistent state
-		 */
-		rt2x00lib_config(rt2x00dev, conf, changed);
+	/*
+	 * After the radio has been enabled we need to configure
+	 * the antenna to the default settings. rt2x00lib_config_antenna()
+	 * should determine if any action should be taken based on
+	 * checking if diversity has been enabled or no antenna changes
+	 * have been made since the last configuration change.
+	 */
+	rt2x00lib_config_antenna(rt2x00dev, rt2x00dev->default_ant);
 
-		/*
-		 * The radio was enabled, configure the antenna to the
-		 * default settings, the link tuner will later start
-		 * continue configuring the antenna based on the software
-		 * diversity. But for non-diversity configurations, we need
-		 * to have configured the correct state now.
-		 */
-		if (changed & IEEE80211_CONF_CHANGE_RADIO_ENABLED)
-			rt2x00lib_config_antenna(rt2x00dev,
-						 rt2x00dev->default_ant);
-
-		/* Turn RX back on */
-		rt2x00lib_toggle_rx(rt2x00dev, STATE_RADIO_RX_ON);
-	} else {
-		/* Disable the radio */
-		rt2x00lib_disable_radio(rt2x00dev);
-	}
+	/* Turn RX back on */
+	rt2x00lib_toggle_rx(rt2x00dev, STATE_RADIO_RX_ON);
 
 	return 0;
 }
-- 
1.6.3.3

[PATCH 2/7] rt2x00: Use IEEE80211_TX_CTL_MORE_FRAMES flag

[Ivo van Doorn]

Check the IEEE80211_TX_CTL_MORE_FRAMES flag to help determining
if the DMA queue should be kicked. At the moment this is combined
with the ieee80211_has_morefrags() but we might remove that later.

Signed-off-by: Ivo van Doorn <IvDoorn@gmail.com>
---
 drivers/net/wireless/rt2x00/rt2x00queue.c |    3 ++-
 1 files changed, 2 insertions(+), 1 deletions(-)

diff --git a/drivers/net/wireless/rt2x00/rt2x00queue.c b/drivers/net/wireless/rt2x00/rt2x00queue.c
index 44e5b32..65435c9 100644
--- a/drivers/net/wireless/rt2x00/rt2x00queue.c
+++ b/drivers/net/wireless/rt2x00/rt2x00queue.c
@@ -324,7 +324,8 @@ static void rt2x00queue_create_tx_descriptor(struct queue_entry *entry,
 	/*
 	 * Check if more fragments are pending
 	 */
-	if (ieee80211_has_morefrags(hdr->frame_control)) {
+	if (ieee80211_has_morefrags(hdr->frame_control) ||
+	    (tx_info->flags & IEEE80211_TX_CTL_MORE_FRAMES)) {
 		__set_bit(ENTRY_TXD_BURST, &txdesc->flags);
 		__set_bit(ENTRY_TXD_MORE_FRAG, &txdesc->flags);
 	}
-- 
1.6.3.3

[PATCH 3/7] rt2x00: Align ieee80211 header to 4-byte boundary for PCI devices

[Ivo van Doorn]

Some hardware require the ieee80211 header to be aligned to a
4-byte boundary before mapping it to the DMA. Otherwise some
frames (like beacons) will not be send out correctly by the
device.

Signed-off-by: Ivo van Doorn <IvDoorn@gmail.com>
---
 drivers/net/wireless/rt2x00/rt2x00queue.c |   12 ++++++++++++
 1 files changed, 12 insertions(+), 0 deletions(-)

diff --git a/drivers/net/wireless/rt2x00/rt2x00queue.c b/drivers/net/wireless/rt2x00/rt2x00queue.c
index 65435c9..e67e339 100644
--- a/drivers/net/wireless/rt2x00/rt2x00queue.c
+++ b/drivers/net/wireless/rt2x00/rt2x00queue.c
@@ -453,9 +453,21 @@ int rt2x00queue_write_tx_frame(struct data_queue *queue, struct sk_buff *skb)
 			rt2x00crypto_tx_remove_iv(skb, &txdesc);
 	}
 
+	/*
+	 * When DMA allocation is required we should guarentee to the
+	 * driver that the DMA is aligned to a 4-byte boundary.
+	 * Aligning the header to this boundary can be done by calling
+	 * rt2x00queue_payload_align with the header length of 0.
+	 * However some drivers require L2 padding to pad the payload
+	 * rather then the header. This could be a requirement for
+	 * PCI and USB devices, while header alignment only is valid
+	 * for PCI devices.
+	 */
 	if (test_bit(DRIVER_REQUIRE_L2PAD, &queue->rt2x00dev->flags))
 		rt2x00queue_payload_align(entry->skb, true,
 					  txdesc.header_length);
+	else if (test_bit(DRIVER_REQUIRE_DMA, &queue->rt2x00dev->flags))
+		rt2x00queue_payload_align(entry->skb, false, 0);
 
 	/*
 	 * It could be possible that the queue was corrupted and this
-- 
1.6.3.3

[PATCH 4/7] rt2x00: Fix quality houskeeping for software diversity

[Ivo van Doorn]

From: Lars Ericsson <Lars_Ericsson@telia.com>

Antanna quality statistics is not handled correctly, which leads to
software diversity being shutdown completly.

The main problem is that during antenna diversity statistics can
be reset resulting in loosing the signal strength just before
evaluation.

rssi history is not updated correctly leading to incorrect comparison
material for basing antenna switching on.

Signed-off-by: Lars Ericsson <Lars_Ericsson@telia.com>
Signed-off-by: Ivo van Doorn <IvDoorn@gmail.com>
---
 drivers/net/wireless/rt2x00/rt2x00.h     |   11 ++---
 drivers/net/wireless/rt2x00/rt2x00link.c |   77 +++++++++++++-----------------
 2 files changed, 38 insertions(+), 50 deletions(-)

diff --git a/drivers/net/wireless/rt2x00/rt2x00.h b/drivers/net/wireless/rt2x00/rt2x00.h
index ee9afab..aa3ff0a 100644
--- a/drivers/net/wireless/rt2x00/rt2x00.h
+++ b/drivers/net/wireless/rt2x00/rt2x00.h
@@ -245,14 +245,11 @@ struct link_ant {
 	struct antenna_setup active;
 
 	/*
-	 * RSSI information for the different antennas.
-	 * These statistics are used to determine when
-	 * to switch antenna when using software diversity.
-	 *
-	 *        rssi[0] -> Antenna A RSSI
-	 *        rssi[1] -> Antenna B RSSI
+	 * RSSI history information for the antenna.
+	 * Used to determine when to switch antenna
+	 * when using software diversity.
 	 */
-	int rssi_history[2];
+	int rssi_history;
 
 	/*
 	 * Current RSSI average of the currently active antenna.
diff --git a/drivers/net/wireless/rt2x00/rt2x00link.c b/drivers/net/wireless/rt2x00/rt2x00link.c
index fe951dc..dd68f3a 100644
--- a/drivers/net/wireless/rt2x00/rt2x00link.c
+++ b/drivers/net/wireless/rt2x00/rt2x00link.c
@@ -103,39 +103,21 @@ static int rt2x00link_antenna_get_link_rssi(struct rt2x00_dev *rt2x00dev)
 	return DEFAULT_RSSI;
 }
 
-static int rt2x00link_antenna_get_rssi_history(struct rt2x00_dev *rt2x00dev,
-					       enum antenna antenna)
+static int rt2x00link_antenna_get_rssi_history(struct rt2x00_dev *rt2x00dev)
 {
 	struct link_ant *ant = &rt2x00dev->link.ant;
 
-	if (ant->rssi_history[antenna - ANTENNA_A])
-		return ant->rssi_history[antenna - ANTENNA_A];
+	if (ant->rssi_history)
+		return ant->rssi_history;
 	return DEFAULT_RSSI;
 }
-/* Small wrapper for rt2x00link_antenna_get_rssi_history() */
-#define rt2x00link_antenna_get_rssi_rx_history(__dev) \
-	rt2x00link_antenna_get_rssi_history((__dev), \
-					    (__dev)->link.ant.active.rx)
-#define rt2x00link_antenna_get_rssi_tx_history(__dev) \
-	rt2x00link_antenna_get_rssi_history((__dev), \
-					    (__dev)->link.ant.active.tx)
 
 static void rt2x00link_antenna_update_rssi_history(struct rt2x00_dev *rt2x00dev,
-						   enum antenna antenna,
 						   int rssi)
 {
 	struct link_ant *ant = &rt2x00dev->link.ant;
-	ant->rssi_history[ant->active.rx - ANTENNA_A] = rssi;
+	ant->rssi_history = rssi;
 }
-/* Small wrapper for rt2x00link_antenna_get_rssi_history() */
-#define rt2x00link_antenna_update_rssi_rx_history(__dev, __rssi) \
-	rt2x00link_antenna_update_rssi_history((__dev), \
-					       (__dev)->link.ant.active.rx, \
-					       (__rssi))
-#define rt2x00link_antenna_update_rssi_tx_history(__dev, __rssi) \
-	rt2x00link_antenna_update_rssi_history((__dev), \
-					       (__dev)->link.ant.active.tx, \
-					       (__rssi))
 
 static void rt2x00link_antenna_reset(struct rt2x00_dev *rt2x00dev)
 {
@@ -146,8 +128,10 @@ static void rt2x00lib_antenna_diversity_sample(struct rt2x00_dev *rt2x00dev)
 {
 	struct link_ant *ant = &rt2x00dev->link.ant;
 	struct antenna_setup new_ant;
-	int sample_a = rt2x00link_antenna_get_rssi_history(rt2x00dev, ANTENNA_A);
-	int sample_b = rt2x00link_antenna_get_rssi_history(rt2x00dev, ANTENNA_B);
+	int other_antenna;
+
+	int sample_current = rt2x00link_antenna_get_link_rssi(rt2x00dev);
+	int sample_other = rt2x00link_antenna_get_rssi_history(rt2x00dev);
 
 	memcpy(&new_ant, &ant->active, sizeof(new_ant));
 
@@ -161,17 +145,22 @@ static void rt2x00lib_antenna_diversity_sample(struct rt2x00_dev *rt2x00dev)
 	 * from both antennas. It now is time to determine
 	 * which antenna demonstrated the best performance.
 	 * When we are already on the antenna with the best
-	 * performance, then there really is nothing for us
-	 * left to do.
+	 * performance, just create a good starting point
+	 * for the history and we are done.
 	 */
-	if (sample_a == sample_b)
+	if (sample_current >= sample_other) {
+		rt2x00link_antenna_update_rssi_history(rt2x00dev,
+			sample_current);
 		return;
+	}
+
+	other_antenna = (ant->active.rx == ANTENNA_A) ? ANTENNA_B : ANTENNA_A;
 
 	if (ant->flags & ANTENNA_RX_DIVERSITY)
-		new_ant.rx = (sample_a > sample_b) ? ANTENNA_A : ANTENNA_B;
+		new_ant.rx = other_antenna;
 
 	if (ant->flags & ANTENNA_TX_DIVERSITY)
-		new_ant.tx = (sample_a > sample_b) ? ANTENNA_A : ANTENNA_B;
+		new_ant.tx = other_antenna;
 
 	rt2x00lib_config_antenna(rt2x00dev, new_ant);
 }
@@ -190,8 +179,8 @@ static void rt2x00lib_antenna_diversity_eval(struct rt2x00_dev *rt2x00dev)
 	 * after that update the history with the current value.
 	 */
 	rssi_curr = rt2x00link_antenna_get_link_rssi(rt2x00dev);
-	rssi_old = rt2x00link_antenna_get_rssi_rx_history(rt2x00dev);
-	rt2x00link_antenna_update_rssi_rx_history(rt2x00dev, rssi_curr);
+	rssi_old = rt2x00link_antenna_get_rssi_history(rt2x00dev);
+	rt2x00link_antenna_update_rssi_history(rt2x00dev, rssi_curr);
 
 	/*
 	 * Legacy driver indicates that we should swap antenna's
@@ -216,7 +205,7 @@ static void rt2x00lib_antenna_diversity_eval(struct rt2x00_dev *rt2x00dev)
 	rt2x00lib_config_antenna(rt2x00dev, new_ant);
 }
 
-static void rt2x00lib_antenna_diversity(struct rt2x00_dev *rt2x00dev)
+static bool rt2x00lib_antenna_diversity(struct rt2x00_dev *rt2x00dev)
 {
 	struct link_ant *ant = &rt2x00dev->link.ant;
 	unsigned int flags = ant->flags;
@@ -238,7 +227,7 @@ static void rt2x00lib_antenna_diversity(struct rt2x00_dev *rt2x00dev)
 	if (!(ant->flags & ANTENNA_RX_DIVERSITY) &&
 	    !(ant->flags & ANTENNA_TX_DIVERSITY)) {
 		ant->flags = 0;
-		return;
+		return true;
 	}
 
 	/* Update flags */
@@ -250,10 +239,15 @@ static void rt2x00lib_antenna_diversity(struct rt2x00_dev *rt2x00dev)
 	 * the data. The latter should only be performed once
 	 * every 2 seconds.
 	 */
-	if (ant->flags & ANTENNA_MODE_SAMPLE)
+	if (ant->flags & ANTENNA_MODE_SAMPLE) {
 		rt2x00lib_antenna_diversity_sample(rt2x00dev);
-	else if (rt2x00dev->link.count & 1)
+		return true;
+	} else if (rt2x00dev->link.count & 1) {
 		rt2x00lib_antenna_diversity_eval(rt2x00dev);
+		return true;
+	}
+
+	return false;
 }
 
 void rt2x00link_update_stats(struct rt2x00_dev *rt2x00dev,
@@ -451,15 +445,12 @@ static void rt2x00link_tuner(struct work_struct *work)
 	rt2x00leds_led_quality(rt2x00dev, link->avg_rssi);
 
 	/*
-	 * Evaluate antenna setup, make this the last step since this could
-	 * possibly reset some statistics.
-	 */
-	rt2x00lib_antenna_diversity(rt2x00dev);
-
-	/*
-	 * Reset the quality counters which recounted during each period.
+	 * Evaluate antenna setup, make this the last step when
+	 * rt2x00lib_antenna_diversity made changes the quality
+	 * statistics will be reset.
 	 */
-	rt2x00link_reset_qual(rt2x00dev);
+	if (rt2x00lib_antenna_diversity(rt2x00dev))
+		rt2x00link_reset_qual(rt2x00dev);
 
 	/*
 	 * Increase tuner counter, and reschedule the next link tuner run.
-- 
1.6.3.3

[PATCH 5/7] rt2x00: Fix rounding errors in RSSI average calculation

[Ivo van Doorn]

From: Lars Ericsson <Lars_Ericsson@telia.com>

Small changes in signal level was not detected up by the
MOVING_AVERAGE() due to a rounding error, using 'int' type.

rt2x00lib_antenna_diversity_eval:
rssi:	  -62 -62 -62 -62 -62 -62 -62 -62 -62 -62 -62 -62 -62 -62 -62
rssi_avg: -57 -57 -57 -57 -57 -57 -57 -57 -57 -57 -57 -57 -57 -57 -57

The signal level reported back could be significantly (5dBm)
different from the actual value. A level +3dBm is the same as
double the AP output power.

Signed-off-by: Lars Ericsson <Lars_Ericsson@telia.com>
Signed-off-by: Ivo van Doorn <IvDoorn@gmail.com>
---
 drivers/net/wireless/rt2x00/rt2x00.h     |   15 ++++++-
 drivers/net/wireless/rt2x00/rt2x00link.c |   65 ++++++++++++++++++------------
 2 files changed, 52 insertions(+), 28 deletions(-)

diff --git a/drivers/net/wireless/rt2x00/rt2x00.h b/drivers/net/wireless/rt2x00/rt2x00.h
index aa3ff0a..19ca146 100644
--- a/drivers/net/wireless/rt2x00/rt2x00.h
+++ b/drivers/net/wireless/rt2x00/rt2x00.h
@@ -134,6 +134,17 @@
 				  GET_DURATION(IEEE80211_HEADER + ACK_SIZE, 10) )
 
 /*
+ * Structure for average calculation
+ * The avg field contains the actual average value,
+ * but avg_weight is internally used during calculations
+ * to prevent rounding errors.
+ */
+struct avg_val {
+	int avg;
+	int avg_weight;
+};
+
+/*
  * Chipset identification
  * The chipset on the device is composed of a RT and RF chip.
  * The chipset combination is important for determining device capabilities.
@@ -256,7 +267,7 @@ struct link_ant {
 	 * Similar to the avg_rssi in the link_qual structure
 	 * this value is updated by using the walking average.
 	 */
-	int rssi_ant;
+	struct avg_val rssi_ant;
 };
 
 /*
@@ -285,7 +296,7 @@ struct link {
 	/*
 	 * Currently active average RSSI value
 	 */
-	int avg_rssi;
+	struct avg_val avg_rssi;
 
 	/*
 	 * Currently precalculated percentages of successful
diff --git a/drivers/net/wireless/rt2x00/rt2x00link.c b/drivers/net/wireless/rt2x00/rt2x00link.c
index dd68f3a..c64db0b 100644
--- a/drivers/net/wireless/rt2x00/rt2x00link.c
+++ b/drivers/net/wireless/rt2x00/rt2x00link.c
@@ -46,7 +46,15 @@
 #define DEFAULT_PERCENTAGE	50
 
 /*
- * Small helper macro to work with moving/walking averages.
+ * Small helper macro for percentage calculation
+ * This is a very simple macro with the only catch that it will
+ * produce a default value in case no total value was provided.
+ */
+#define PERCENTAGE(__value, __total) \
+	( (__total) ? (((__value) * 100) / (__total)) : (DEFAULT_PERCENTAGE) )
+
+/*
+ * Helper struct and macro to work with moving/walking averages.
  * When adding a value to the average value the following calculation
  * is needed:
  *
@@ -60,18 +68,28 @@
  * for a few minutes but when the device is moved away from the AP
  * the average will not decrease fast enough to compensate.
  * The walking average compensates this and will move towards
- * the new values correctly allowing a effective link tuning.
+ * the new values correctly allowing a effective link tuning,
+ * the speed of the average moving towards other values depends
+ * on the value for the number of samples. The higher the number
+ * of samples, the slower the average will move.
+ * We use two variables to keep track of the average value to
+ * compensate for the rounding errors. This can be a significant
+ * error (>5dBm) if the factor is too low.
  */
-#define MOVING_AVERAGE(__avg, __val, __samples) \
-	( (((__avg) * ((__samples) - 1)) + (__val)) / (__samples) )
-
-/*
- * Small helper macro for percentage calculation
- * This is a very simple macro with the only catch that it will
- * produce a default value in case no total value was provided.
- */
-#define PERCENTAGE(__value, __total) \
-	( (__total) ? (((__value) * 100) / (__total)) : (DEFAULT_PERCENTAGE) )
+#define AVG_SAMPLES	8
+#define AVG_FACTOR	1000
+#define MOVING_AVERAGE(__avg, __val) \
+({ \
+	struct avg_val __new; \
+	__new.avg_weight = \
+	    (__avg).avg_weight  ? \
+		((((__avg).avg_weight * ((AVG_SAMPLES) - 1)) + \
+		  ((__val) * (AVG_FACTOR))) / \
+		 (AVG_SAMPLES) ) : \
+		((__val) * (AVG_FACTOR)); \
+	__new.avg = __new.avg_weight / (AVG_FACTOR); \
+	__new; \
+})
 
 /*
  * For calculating the Signal quality we have determined
@@ -98,8 +116,8 @@ static int rt2x00link_antenna_get_link_rssi(struct rt2x00_dev *rt2x00dev)
 {
 	struct link_ant *ant = &rt2x00dev->link.ant;
 
-	if (ant->rssi_ant && rt2x00dev->link.qual.rx_success)
-		return ant->rssi_ant;
+	if (ant->rssi_ant.avg && rt2x00dev->link.qual.rx_success)
+		return ant->rssi_ant.avg;
 	return DEFAULT_RSSI;
 }
 
@@ -121,7 +139,8 @@ static void rt2x00link_antenna_update_rssi_history(struct rt2x00_dev *rt2x00dev,
 
 static void rt2x00link_antenna_reset(struct rt2x00_dev *rt2x00dev)
 {
-	rt2x00dev->link.ant.rssi_ant = 0;
+	rt2x00dev->link.ant.rssi_ant.avg = 0;
+	rt2x00dev->link.ant.rssi_ant.avg_weight = 0;
 }
 
 static void rt2x00lib_antenna_diversity_sample(struct rt2x00_dev *rt2x00dev)
@@ -258,8 +277,6 @@ void rt2x00link_update_stats(struct rt2x00_dev *rt2x00dev,
 	struct link_qual *qual = &rt2x00dev->link.qual;
 	struct link_ant *ant = &rt2x00dev->link.ant;
 	struct ieee80211_hdr *hdr = (struct ieee80211_hdr *)skb->data;
-	int avg_rssi = rxdesc->rssi;
-	int ant_rssi = rxdesc->rssi;
 
 	/*
 	 * Frame was received successfully since non-succesfull
@@ -279,16 +296,12 @@ void rt2x00link_update_stats(struct rt2x00_dev *rt2x00dev,
 	/*
 	 * Update global RSSI
 	 */
-	if (link->avg_rssi)
-		avg_rssi = MOVING_AVERAGE(link->avg_rssi, rxdesc->rssi, 8);
-	link->avg_rssi = avg_rssi;
+	link->avg_rssi = MOVING_AVERAGE(link->avg_rssi, rxdesc->rssi);
 
 	/*
 	 * Update antenna RSSI
 	 */
-	if (ant->rssi_ant)
-		ant_rssi = MOVING_AVERAGE(ant->rssi_ant, rxdesc->rssi, 8);
-	ant->rssi_ant = ant_rssi;
+	ant->rssi_ant = MOVING_AVERAGE(ant->rssi_ant, rxdesc->rssi);
 }
 
 static void rt2x00link_precalculate_signal(struct rt2x00_dev *rt2x00dev)
@@ -421,10 +434,10 @@ static void rt2x00link_tuner(struct work_struct *work)
 	 * collect the RSSI data we could use this. Otherwise we
 	 * must fallback to the default RSSI value.
 	 */
-	if (!link->avg_rssi || !qual->rx_success)
+	if (!link->avg_rssi.avg || !qual->rx_success)
 		qual->rssi = DEFAULT_RSSI;
 	else
-		qual->rssi = link->avg_rssi;
+		qual->rssi = link->avg_rssi.avg;
 
 	/*
 	 * Only perform the link tuning when Link tuning
@@ -442,7 +455,7 @@ static void rt2x00link_tuner(struct work_struct *work)
 	/*
 	 * Send a signal to the led to update the led signal strength.
 	 */
-	rt2x00leds_led_quality(rt2x00dev, link->avg_rssi);
+	rt2x00leds_led_quality(rt2x00dev, qual->rssi);
 
 	/*
 	 * Evaluate antenna setup, make this the last step when
-- 
1.6.3.3

[PATCH 6/7] rt2x00: Fix for race condition while update beacon

[Ivo van Doorn]

From: Igor Perminov <igor.perminov@inbox.ru>

The patch "Implement set_tim callback for all drivers" can cause kernel
oops in rt73usb_write_beacon. The oops is caused by one of the following
race conditions:
* In case of two near calls to set_tim: rt2x00lib_beacondone_iter is
cleaning the beacon skb, whereas rt73usb_write_beacon is still using it.
* In case of two near updates of beacon: first as the result of set_tim
and second as the result of a call from an application (e.g. hostapd).
This patch fixes the race condition by rearranging the update logic and
guarding rt2x00_intf->beacon->skb with a mutex.

Signed-off-by: Igor Perminov <igor.perminov@inbox.ru>
Signed-off-by: Ivo van Doorn <IvDoorn@gmail.com>
---
 drivers/net/wireless/rt2x00/rt2x00.h      |    5 +++++
 drivers/net/wireless/rt2x00/rt2x00dev.c   |    7 -------
 drivers/net/wireless/rt2x00/rt2x00mac.c   |    1 +
 drivers/net/wireless/rt2x00/rt2x00queue.c |   15 ++++++++++++++-
 4 files changed, 20 insertions(+), 8 deletions(-)

diff --git a/drivers/net/wireless/rt2x00/rt2x00.h b/drivers/net/wireless/rt2x00/rt2x00.h
index 19ca146..806ef60 100644
--- a/drivers/net/wireless/rt2x00/rt2x00.h
+++ b/drivers/net/wireless/rt2x00/rt2x00.h
@@ -334,6 +334,11 @@ struct rt2x00_intf {
 	u8 bssid[ETH_ALEN];
 
 	/*
+	 * beacon->skb must be protected with the mutex.
+	 */
+	struct mutex beacon_skb_mutex;
+
+	/*
 	 * Entry in the beacon queue which belongs to
 	 * this interface. Each interface has its own
 	 * dedicated beacon entry.
diff --git a/drivers/net/wireless/rt2x00/rt2x00dev.c b/drivers/net/wireless/rt2x00/rt2x00dev.c
index e0348cc..b6676c6 100644
--- a/drivers/net/wireless/rt2x00/rt2x00dev.c
+++ b/drivers/net/wireless/rt2x00/rt2x00dev.c
@@ -186,7 +186,6 @@ static void rt2x00lib_intf_scheduled(struct work_struct *work)
 static void rt2x00lib_beacondone_iter(void *data, u8 *mac,
 				      struct ieee80211_vif *vif)
 {
-	struct rt2x00_dev *rt2x00dev = data;
 	struct rt2x00_intf *intf = vif_to_intf(vif);
 
 	if (vif->type != NL80211_IFTYPE_AP &&
@@ -195,12 +194,6 @@ static void rt2x00lib_beacondone_iter(void *data, u8 *mac,
 	    vif->type != NL80211_IFTYPE_WDS)
 		return;
 
-	/*
-	 * Clean up the beacon skb.
-	 */
-	rt2x00queue_free_skb(rt2x00dev, intf->beacon->skb);
-	intf->beacon->skb = NULL;
-
 	spin_lock(&intf->lock);
 	intf->delayed_flags |= DELAYED_UPDATE_BEACON;
 	spin_unlock(&intf->lock);
diff --git a/drivers/net/wireless/rt2x00/rt2x00mac.c b/drivers/net/wireless/rt2x00/rt2x00mac.c
index 4164fce..74451f9 100644
--- a/drivers/net/wireless/rt2x00/rt2x00mac.c
+++ b/drivers/net/wireless/rt2x00/rt2x00mac.c
@@ -274,6 +274,7 @@ int rt2x00mac_add_interface(struct ieee80211_hw *hw,
 
 	spin_lock_init(&intf->lock);
 	spin_lock_init(&intf->seqlock);
+	mutex_init(&intf->beacon_skb_mutex);
 	intf->beacon = entry;
 
 	if (conf->type == NL80211_IFTYPE_AP)
diff --git a/drivers/net/wireless/rt2x00/rt2x00queue.c b/drivers/net/wireless/rt2x00/rt2x00queue.c
index e67e339..06af823 100644
--- a/drivers/net/wireless/rt2x00/rt2x00queue.c
+++ b/drivers/net/wireless/rt2x00/rt2x00queue.c
@@ -503,14 +503,25 @@ int rt2x00queue_update_beacon(struct rt2x00_dev *rt2x00dev,
 	if (unlikely(!intf->beacon))
 		return -ENOBUFS;
 
+	mutex_lock(&intf->beacon_skb_mutex);
+
+	/*
+	 * Clean up the beacon skb.
+	 */
+	rt2x00queue_free_skb(rt2x00dev, intf->beacon->skb);
+	intf->beacon->skb = NULL;
+
 	if (!enable_beacon) {
 		rt2x00dev->ops->lib->kill_tx_queue(rt2x00dev, QID_BEACON);
+		mutex_unlock(&intf->beacon_skb_mutex);
 		return 0;
 	}
 
 	intf->beacon->skb = ieee80211_beacon_get(rt2x00dev->hw, vif);
-	if (!intf->beacon->skb)
+	if (!intf->beacon->skb) {
+		mutex_unlock(&intf->beacon_skb_mutex);
 		return -ENOMEM;
+	}
 
 	/*
 	 * Copy all TX descriptor information into txdesc,
@@ -548,6 +559,8 @@ int rt2x00queue_update_beacon(struct rt2x00_dev *rt2x00dev,
 	rt2x00dev->ops->lib->write_beacon(intf->beacon);
 	rt2x00dev->ops->lib->kick_tx_queue(rt2x00dev, QID_BEACON);
 
+	mutex_unlock(&intf->beacon_skb_mutex);
+
 	return 0;
 }
 
-- 
1.6.3.3

[PATCH 7/7] [PATCH] rt2x00: FIF_PSPOLL filter flag support

[Ivo van Doorn]

From: Igor Perminov <igor.perminov@inbox.ru>

This patch implements FIF_PSPOLL filter flag support in rt2x00 drivers,
which has been introduced in mac80211 (see
http://marc.info/?l=linux-wireless&m=124897986330807&w=2).

Signed-off-by: Igor Perminov <igor.perminov@inbox.ru>
Signed-off-by: Ivo van Doorn <IvDoorn@gmail.com>
---
 drivers/net/wireless/rt2x00/rt2800usb.c |    9 ++++++++-
 drivers/net/wireless/rt2x00/rt2x00.h    |    2 ++
 drivers/net/wireless/rt2x00/rt2x00mac.c |   17 +++++++++++++++++
 drivers/net/wireless/rt2x00/rt61pci.c   |    8 +++++++-
 drivers/net/wireless/rt2x00/rt73usb.c   |    8 +++++++-
 5 files changed, 41 insertions(+), 3 deletions(-)

diff --git a/drivers/net/wireless/rt2x00/rt2800usb.c b/drivers/net/wireless/rt2x00/rt2800usb.c
index 9efb417..2de0389 100644
--- a/drivers/net/wireless/rt2x00/rt2800usb.c
+++ b/drivers/net/wireless/rt2x00/rt2800usb.c
@@ -518,7 +518,7 @@ static void rt2800usb_config_filter(struct rt2x00_dev *rt2x00dev,
 	rt2x00_set_field32(&reg, RX_FILTER_CFG_DROP_RTS,
 			   !(filter_flags & FIF_CONTROL));
 	rt2x00_set_field32(&reg, RX_FILTER_CFG_DROP_PSPOLL,
-			   !(filter_flags & FIF_CONTROL));
+			   !(filter_flags & FIF_PSPOLL));
 	rt2x00_set_field32(&reg, RX_FILTER_CFG_DROP_BA, 1);
 	rt2x00_set_field32(&reg, RX_FILTER_CFG_DROP_BAR, 0);
 	rt2x00_set_field32(&reg, RX_FILTER_CFG_DROP_CNTL,
@@ -2624,6 +2624,13 @@ static int rt2800usb_probe_hw(struct rt2x00_dev *rt2x00dev)
 		return retval;
 
 	/*
+	 * This device has multiple filters for control frames
+	 * and has a separate filter for PS Poll frames.
+	 */
+	__set_bit(DRIVER_SUPPORT_CONTROL_FILTERS, &rt2x00dev->flags);
+	__set_bit(DRIVER_SUPPORT_CONTROL_FILTER_PSPOLL, &rt2x00dev->flags);
+
+	/*
 	 * This device requires firmware.
 	 */
 	__set_bit(DRIVER_REQUIRE_FIRMWARE, &rt2x00dev->flags);
diff --git a/drivers/net/wireless/rt2x00/rt2x00.h b/drivers/net/wireless/rt2x00/rt2x00.h
index 806ef60..99e8959 100644
--- a/drivers/net/wireless/rt2x00/rt2x00.h
+++ b/drivers/net/wireless/rt2x00/rt2x00.h
@@ -624,6 +624,8 @@ enum rt2x00_flags {
 	 */
 	CONFIG_SUPPORT_HW_BUTTON,
 	CONFIG_SUPPORT_HW_CRYPTO,
+	DRIVER_SUPPORT_CONTROL_FILTERS,
+	DRIVER_SUPPORT_CONTROL_FILTER_PSPOLL,
 
 	/*
 	 * Driver configuration
diff --git a/drivers/net/wireless/rt2x00/rt2x00mac.c b/drivers/net/wireless/rt2x00/rt2x00mac.c
index 74451f9..cb7b6d4 100644
--- a/drivers/net/wireless/rt2x00/rt2x00mac.c
+++ b/drivers/net/wireless/rt2x00/rt2x00mac.c
@@ -392,6 +392,7 @@ void rt2x00mac_configure_filter(struct ieee80211_hw *hw,
 	    FIF_FCSFAIL |
 	    FIF_PLCPFAIL |
 	    FIF_CONTROL |
+	    FIF_PSPOLL |
 	    FIF_OTHER_BSS |
 	    FIF_PROMISC_IN_BSS;
 
@@ -407,6 +408,22 @@ void rt2x00mac_configure_filter(struct ieee80211_hw *hw,
 		*total_flags |= FIF_PROMISC_IN_BSS | FIF_OTHER_BSS;
 
 	/*
+	 * If the device has a single filter for all control frames,
+	 * FIF_CONTROL and FIF_PSPOLL flags imply each other.
+	 * And if the device has more than one filter for control frames
+	 * of different types, but has no a separate filter for PS Poll frames,
+	 * FIF_CONTROL flag implies FIF_PSPOLL.
+	 */
+	if (!test_bit(DRIVER_SUPPORT_CONTROL_FILTERS, &rt2x00dev->flags)) {
+		if (*total_flags & FIF_CONTROL || *total_flags & FIF_PSPOLL)
+			*total_flags |= FIF_CONTROL | FIF_PSPOLL;
+	}
+	if (!test_bit(DRIVER_SUPPORT_CONTROL_FILTER_PSPOLL, &rt2x00dev->flags)) {
+		if (*total_flags & FIF_CONTROL)
+			*total_flags |= FIF_PSPOLL;
+	}
+
+	/*
 	 * Check if there is any work left for us.
 	 */
 	if (rt2x00dev->packet_filter == *total_flags)
diff --git a/drivers/net/wireless/rt2x00/rt61pci.c b/drivers/net/wireless/rt2x00/rt61pci.c
index e20dd74..3447997 100644
--- a/drivers/net/wireless/rt2x00/rt61pci.c
+++ b/drivers/net/wireless/rt2x00/rt61pci.c
@@ -530,7 +530,7 @@ static void rt61pci_config_filter(struct rt2x00_dev *rt2x00dev,
 	rt2x00_set_field32(&reg, TXRX_CSR0_DROP_PHYSICAL,
 			   !(filter_flags & FIF_PLCPFAIL));
 	rt2x00_set_field32(&reg, TXRX_CSR0_DROP_CONTROL,
-			   !(filter_flags & FIF_CONTROL));
+			   !(filter_flags & (FIF_CONTROL | FIF_PSPOLL)));
 	rt2x00_set_field32(&reg, TXRX_CSR0_DROP_NOT_TO_ME,
 			   !(filter_flags & FIF_PROMISC_IN_BSS));
 	rt2x00_set_field32(&reg, TXRX_CSR0_DROP_TO_DS,
@@ -2624,6 +2624,12 @@ static int rt61pci_probe_hw(struct rt2x00_dev *rt2x00dev)
 		return retval;
 
 	/*
+	 * This device has multiple filters for control frames,
+	 * but has no a separate filter for PS Poll frames.
+	 */
+	__set_bit(DRIVER_SUPPORT_CONTROL_FILTERS, &rt2x00dev->flags);
+
+	/*
 	 * This device requires firmware and DMA mapped skbs.
 	 */
 	__set_bit(DRIVER_REQUIRE_FIRMWARE, &rt2x00dev->flags);
diff --git a/drivers/net/wireless/rt2x00/rt73usb.c b/drivers/net/wireless/rt2x00/rt73usb.c
index 4f9b177..4b9955b 100644
--- a/drivers/net/wireless/rt2x00/rt73usb.c
+++ b/drivers/net/wireless/rt2x00/rt73usb.c
@@ -493,7 +493,7 @@ static void rt73usb_config_filter(struct rt2x00_dev *rt2x00dev,
 	rt2x00_set_field32(&reg, TXRX_CSR0_DROP_PHYSICAL,
 			   !(filter_flags & FIF_PLCPFAIL));
 	rt2x00_set_field32(&reg, TXRX_CSR0_DROP_CONTROL,
-			   !(filter_flags & FIF_CONTROL));
+			   !(filter_flags & (FIF_CONTROL | FIF_PSPOLL)));
 	rt2x00_set_field32(&reg, TXRX_CSR0_DROP_NOT_TO_ME,
 			   !(filter_flags & FIF_PROMISC_IN_BSS));
 	rt2x00_set_field32(&reg, TXRX_CSR0_DROP_TO_DS,
@@ -2144,6 +2144,12 @@ static int rt73usb_probe_hw(struct rt2x00_dev *rt2x00dev)
 		return retval;
 
 	/*
+	 * This device has multiple filters for control frames,
+	 * but has no a separate filter for PS Poll frames.
+	 */
+	__set_bit(DRIVER_SUPPORT_CONTROL_FILTERS, &rt2x00dev->flags);
+
+	/*
 	 * This device requires firmware.
 	 */
 	__set_bit(DRIVER_REQUIRE_FIRMWARE, &rt2x00dev->flags);
-- 
1.6.3.3