11 files changed, 159 insertions, 3 deletions

diff --git a/drivers/net/wireless/rt2x00/rt2500usb.c b/drivers/net/wireless/rt2x00/rt2500usb.c
index 0b7888d43f37..009323e6c20f 100644
--- a/drivers/net/wireless/rt2x00/rt2500usb.c
+++ b/drivers/net/wireless/rt2x00/rt2500usb.c
@@ -1736,6 +1736,7 @@ static int rt2500usb_probe_hw(struct rt2x00_dev *rt2x00dev)
 		__set_bit(CONFIG_SUPPORT_HW_CRYPTO, &rt2x00dev->flags);
 		__set_bit(DRIVER_REQUIRE_COPY_IV, &rt2x00dev->flags);
 	}
+	__set_bit(DRIVER_SUPPORT_WATCHDOG, &rt2x00dev->flags);
 
 	/*
 	 * Set the rssi offset.
@@ -1772,6 +1773,7 @@ static const struct rt2x00lib_ops rt2500usb_rt2x00_ops = {
 	.rfkill_poll		= rt2500usb_rfkill_poll,
 	.link_stats		= rt2500usb_link_stats,
 	.reset_tuner		= rt2500usb_reset_tuner,
+	.watchdog		= rt2x00usb_watchdog,
 	.write_tx_desc		= rt2500usb_write_tx_desc,
 	.write_beacon		= rt2500usb_write_beacon,
 	.get_tx_data_len	= rt2500usb_get_tx_data_len,
diff --git a/drivers/net/wireless/rt2x00/rt2800usb.c b/drivers/net/wireless/rt2x00/rt2800usb.c
index e4ab4db66ca0..5aa7563155cd 100644
--- a/drivers/net/wireless/rt2x00/rt2800usb.c
+++ b/drivers/net/wireless/rt2x00/rt2800usb.c
@@ -633,6 +633,7 @@ static int rt2800usb_probe_hw(struct rt2x00_dev *rt2x00dev)
 	if (!modparam_nohwcrypt)
 		__set_bit(CONFIG_SUPPORT_HW_CRYPTO, &rt2x00dev->flags);
 	__set_bit(DRIVER_SUPPORT_LINK_TUNING, &rt2x00dev->flags);
+	__set_bit(DRIVER_SUPPORT_WATCHDOG, &rt2x00dev->flags);
 
 	/*
 	 * Set the rssi offset.
@@ -655,6 +656,7 @@ static const struct rt2x00lib_ops rt2800usb_rt2x00_ops = {
 	.link_stats		= rt2800_link_stats,
 	.reset_tuner		= rt2800_reset_tuner,
 	.link_tuner		= rt2800_link_tuner,
+	.watchdog		= rt2x00usb_watchdog,
 	.write_tx_desc		= rt2800usb_write_tx_desc,
 	.write_tx_data		= rt2800usb_write_tx_data,
 	.write_beacon		= rt2800_write_beacon,
diff --git a/drivers/net/wireless/rt2x00/rt2x00.h b/drivers/net/wireless/rt2x00/rt2x00.h
index bf5e3f37e705..97b6261fee4f 100644
--- a/drivers/net/wireless/rt2x00/rt2x00.h
+++ b/drivers/net/wireless/rt2x00/rt2x00.h
@@ -332,6 +332,11 @@ struct link {
 	 * Work structure for scheduling periodic link tuning.
 	 */
 	struct delayed_work work;
+
+	/*
+	 * Work structure for scheduling periodic watchdog monitoring.
+	 */
+	struct delayed_work watchdog_work;
 };
 
 /*
@@ -543,6 +548,7 @@ struct rt2x00lib_ops {
 			     struct link_qual *qual);
 	void (*link_tuner) (struct rt2x00_dev *rt2x00dev,
 			    struct link_qual *qual, const u32 count);
+	void (*watchdog) (struct rt2x00_dev *rt2x00dev);
 
 	/*
 	 * TX control handlers
@@ -648,6 +654,7 @@ enum rt2x00_flags {
 	DRIVER_SUPPORT_CONTROL_FILTERS,
 	DRIVER_SUPPORT_CONTROL_FILTER_PSPOLL,
 	DRIVER_SUPPORT_LINK_TUNING,
+	DRIVER_SUPPORT_WATCHDOG,
 
 	/*
 	 * Driver configuration
diff --git a/drivers/net/wireless/rt2x00/rt2x00dev.c b/drivers/net/wireless/rt2x00/rt2x00dev.c
index 12ee7bdedd02..0906e14b347f 100644
--- a/drivers/net/wireless/rt2x00/rt2x00dev.c
+++ b/drivers/net/wireless/rt2x00/rt2x00dev.c
@@ -70,6 +70,11 @@ int rt2x00lib_enable_radio(struct rt2x00_dev *rt2x00dev)
 	rt2x00lib_toggle_rx(rt2x00dev, STATE_RADIO_RX_ON);
 
 	/*
+	 * Start watchdog monitoring.
+	 */
+	rt2x00link_start_watchdog(rt2x00dev);
+
+	/*
 	 * Start the TX queues.
 	 */
 	ieee80211_wake_queues(rt2x00dev->hw);
@@ -89,6 +94,11 @@ void rt2x00lib_disable_radio(struct rt2x00_dev *rt2x00dev)
 	rt2x00queue_stop_queues(rt2x00dev);
 
 	/*
+	 * Stop watchdog monitoring.
+	 */
+	rt2x00link_stop_watchdog(rt2x00dev);
+
+	/*
 	 * Disable RX.
 	 */
 	rt2x00lib_toggle_rx(rt2x00dev, STATE_RADIO_RX_OFF);
diff --git a/drivers/net/wireless/rt2x00/rt2x00lib.h b/drivers/net/wireless/rt2x00/rt2x00lib.h
index ed27de1de57b..dc5c6574aaf4 100644
--- a/drivers/net/wireless/rt2x00/rt2x00lib.h
+++ b/drivers/net/wireless/rt2x00/rt2x00lib.h
@@ -30,6 +30,7 @@
 /*
  * Interval defines
  */
+#define WATCHDOG_INTERVAL	round_jiffies_relative(HZ)
 #define LINK_TUNE_INTERVAL	round_jiffies_relative(HZ)
 
 /*
@@ -257,11 +258,30 @@ void rt2x00link_stop_tuner(struct rt2x00_dev *rt2x00dev);
 void rt2x00link_reset_tuner(struct rt2x00_dev *rt2x00dev, bool antenna);
 
 /**
- * rt2x00link_register - Initialize link tuning functionality
+ * rt2x00link_start_watchdog - Start periodic watchdog monitoring
  * @rt2x00dev: Pointer to &struct rt2x00_dev.
  *
- * Initialize work structure and all link tuning related
- * parameters. This will not start the link tuning process itself.
+ * This start the watchdog periodic work, this work will
+ *be executed periodically until &rt2x00link_stop_watchdog has
+ * been called.
+ */
+void rt2x00link_start_watchdog(struct rt2x00_dev *rt2x00dev);
+
+/**
+ * rt2x00link_stop_watchdog - Stop periodic watchdog monitoring
+ * @rt2x00dev: Pointer to &struct rt2x00_dev.
+ *
+ * After this function completed the watchdog monitoring will not
+ * be running until &rt2x00link_start_watchdog is called.
+ */
+void rt2x00link_stop_watchdog(struct rt2x00_dev *rt2x00dev);
+
+/**
+ * rt2x00link_register - Initialize link tuning & watchdog functionality
+ * @rt2x00dev: Pointer to &struct rt2x00_dev.
+ *
+ * Initialize work structure and all link tuning and watchdog related
+ * parameters. This will not start the periodic work itself.
  */
 void rt2x00link_register(struct rt2x00_dev *rt2x00dev);
 
diff --git a/drivers/net/wireless/rt2x00/rt2x00link.c b/drivers/net/wireless/rt2x00/rt2x00link.c
index 9acfc5c70389..666cef3f8472 100644
--- a/drivers/net/wireless/rt2x00/rt2x00link.c
+++ b/drivers/net/wireless/rt2x00/rt2x00link.c
@@ -407,7 +407,45 @@ static void rt2x00link_tuner(struct work_struct *work)
 					     &link->work, LINK_TUNE_INTERVAL);
 }
 
+void rt2x00link_start_watchdog(struct rt2x00_dev *rt2x00dev)
+{
+	struct link *link = &rt2x00dev->link;
+
+	if (!test_bit(DEVICE_STATE_PRESENT, &rt2x00dev->flags) ||
+	    !test_bit(DRIVER_SUPPORT_WATCHDOG, &rt2x00dev->flags))
+		return;
+
+	ieee80211_queue_delayed_work(rt2x00dev->hw,
+				     &link->watchdog_work, WATCHDOG_INTERVAL);
+}
+
+void rt2x00link_stop_watchdog(struct rt2x00_dev *rt2x00dev)
+{
+	cancel_delayed_work_sync(&rt2x00dev->link.watchdog_work);
+}
+
+static void rt2x00link_watchdog(struct work_struct *work)
+{
+	struct rt2x00_dev *rt2x00dev =
+	    container_of(work, struct rt2x00_dev, link.watchdog_work.work);
+	struct link *link = &rt2x00dev->link;
+
+	/*
+	 * When the radio is shutting down we should
+	 * immediately cease the watchdog monitoring.
+	 */
+	if (!test_bit(DEVICE_STATE_ENABLED_RADIO, &rt2x00dev->flags))
+		return;
+
+	rt2x00dev->ops->lib->watchdog(rt2x00dev);
+
+	if (test_bit(DEVICE_STATE_PRESENT, &rt2x00dev->flags))
+		ieee80211_queue_delayed_work(rt2x00dev->hw,
+					     &link->watchdog_work, WATCHDOG_INTERVAL);
+}
+
 void rt2x00link_register(struct rt2x00_dev *rt2x00dev)
 {
+	INIT_DELAYED_WORK(&rt2x00dev->link.watchdog_work, rt2x00link_watchdog);
 	INIT_DELAYED_WORK(&rt2x00dev->link.work, rt2x00link_tuner);
 }
diff --git a/drivers/net/wireless/rt2x00/rt2x00queue.c b/drivers/net/wireless/rt2x00/rt2x00queue.c
index 5097fe0f9f51..a3401d301058 100644
--- a/drivers/net/wireless/rt2x00/rt2x00queue.c
+++ b/drivers/net/wireless/rt2x00/rt2x00queue.c
@@ -688,9 +688,11 @@ void rt2x00queue_index_inc(struct data_queue *queue, enum queue_index index)
 
 	if (index == Q_INDEX) {
 		queue->length++;
+		queue->last_index = jiffies;
 	} else if (index == Q_INDEX_DONE) {
 		queue->length--;
 		queue->count++;
+		queue->last_index_done = jiffies;
 	}
 
 	spin_unlock_irqrestore(&queue->lock, irqflags);
@@ -704,6 +706,8 @@ static void rt2x00queue_reset(struct data_queue *queue)
 
 	queue->count = 0;
 	queue->length = 0;
+	queue->last_index = jiffies;
+	queue->last_index_done = jiffies;
 	memset(queue->index, 0, sizeof(queue->index));
 
 	spin_unlock_irqrestore(&queue->lock, irqflags);
diff --git a/drivers/net/wireless/rt2x00/rt2x00queue.h b/drivers/net/wireless/rt2x00/rt2x00queue.h
index bd54f55a8cb9..191e7775a9c0 100644
--- a/drivers/net/wireless/rt2x00/rt2x00queue.h
+++ b/drivers/net/wireless/rt2x00/rt2x00queue.h
@@ -446,6 +446,8 @@ struct data_queue {
 	enum data_queue_qid qid;
 
 	spinlock_t lock;
+	unsigned long last_index;
+	unsigned long last_index_done;
 	unsigned int count;
 	unsigned short limit;
 	unsigned short threshold;
@@ -599,6 +601,15 @@ static inline int rt2x00queue_threshold(struct data_queue *queue)
 }
 
 /**
+ * rt2x00queue_timeout - Check if a timeout occured for this queue
+ * @queue: Queue to check.
+ */
+static inline int rt2x00queue_timeout(struct data_queue *queue)
+{
+	return time_after(queue->last_index, queue->last_index_done + (HZ / 10));
+}
+
+/**
  * _rt2x00_desc_read - Read a word from the hardware descriptor.
  * @desc: Base descriptor address
  * @word: Word index from where the descriptor should be read.
diff --git a/drivers/net/wireless/rt2x00/rt2x00usb.c b/drivers/net/wireless/rt2x00/rt2x00usb.c
index a22837c560fd..ff3a36622d1b 100644
--- a/drivers/net/wireless/rt2x00/rt2x00usb.c
+++ b/drivers/net/wireless/rt2x00/rt2x00usb.c
@@ -292,6 +292,56 @@ void rt2x00usb_kill_tx_queue(struct rt2x00_dev *rt2x00dev,
 }
 EXPORT_SYMBOL_GPL(rt2x00usb_kill_tx_queue);
 
+static void rt2x00usb_watchdog_reset_tx(struct data_queue *queue)
+{
+	struct queue_entry_priv_usb *entry_priv;
+	unsigned short threshold = queue->threshold;
+
+	WARNING(queue->rt2x00dev, "TX queue %d timed out, invoke reset", queue->qid);
+
+	/*
+	 * Temporarily disable the TX queue, this will force mac80211
+	 * to use the other queues until this queue has been restored.
+	 *
+	 * Set the queue threshold to the queue limit. This prevents the
+	 * queue from being enabled during the txdone handler.
+	 */
+	queue->threshold = queue->limit;
+	ieee80211_stop_queue(queue->rt2x00dev->hw, queue->qid);
+
+	/*
+	 * Reset all currently uploaded TX frames.
+	 */
+	while (!rt2x00queue_empty(queue)) {
+		entry_priv = rt2x00queue_get_entry(queue, Q_INDEX_DONE)->priv_data;
+		usb_kill_urb(entry_priv->urb);
+
+		/*
+		 * We need a short delay here to wait for
+		 * the URB to be canceled and invoked the tx_done handler.
+		 */
+		udelay(200);
+	}
+
+	/*
+	 * The queue has been reset, and mac80211 is allowed to use the
+	 * queue again.
+	 */
+	queue->threshold = threshold;
+	ieee80211_wake_queue(queue->rt2x00dev->hw, queue->qid);
+}
+
+void rt2x00usb_watchdog(struct rt2x00_dev *rt2x00dev)
+{
+	struct data_queue *queue;
+
+	tx_queue_for_each(rt2x00dev, queue) {
+		if (rt2x00queue_timeout(queue))
+			rt2x00usb_watchdog_reset_tx(queue);
+	}
+}
+EXPORT_SYMBOL_GPL(rt2x00usb_watchdog);
+
 /*
  * RX data handlers.
  */
diff --git a/drivers/net/wireless/rt2x00/rt2x00usb.h b/drivers/net/wireless/rt2x00/rt2x00usb.h
index 2b7a1889e72f..d3d3ddc40875 100644
--- a/drivers/net/wireless/rt2x00/rt2x00usb.h
+++ b/drivers/net/wireless/rt2x00/rt2x00usb.h
@@ -399,6 +399,16 @@ void rt2x00usb_kick_tx_queue(struct rt2x00_dev *rt2x00dev,
 void rt2x00usb_kill_tx_queue(struct rt2x00_dev *rt2x00dev,
 			      const enum data_queue_qid qid);
 
+/**
+ * rt2x00usb_watchdog - Watchdog for USB communication
+ * @rt2x00dev: Pointer to &struct rt2x00_dev
+ *
+ * Check the health of the USB communication and determine
+ * if timeouts have occured. If this is the case, this function
+ * will reset all communication to restore functionality again.
+ */
+void rt2x00usb_watchdog(struct rt2x00_dev *rt2x00dev);
+
 /*
  * Device initialization handlers.
  */
diff --git a/drivers/net/wireless/rt2x00/rt73usb.c b/drivers/net/wireless/rt2x00/rt73usb.c
index 9ea6a672d4e2..cad07b69c53e 100644
--- a/drivers/net/wireless/rt2x00/rt73usb.c
+++ b/drivers/net/wireless/rt2x00/rt73usb.c
@@ -2136,6 +2136,7 @@ static int rt73usb_probe_hw(struct rt2x00_dev *rt2x00dev)
 	if (!modparam_nohwcrypt)
 		__set_bit(CONFIG_SUPPORT_HW_CRYPTO, &rt2x00dev->flags);
 	__set_bit(DRIVER_SUPPORT_LINK_TUNING, &rt2x00dev->flags);
+	__set_bit(DRIVER_SUPPORT_WATCHDOG, &rt2x00dev->flags);
 
 	/*
 	 * Set the rssi offset.
@@ -2251,6 +2252,7 @@ static const struct rt2x00lib_ops rt73usb_rt2x00_ops = {
 	.link_stats		= rt73usb_link_stats,
 	.reset_tuner		= rt73usb_reset_tuner,
 	.link_tuner		= rt73usb_link_tuner,
+	.watchdog		= rt2x00usb_watchdog,
 	.write_tx_desc		= rt73usb_write_tx_desc,
 	.write_beacon		= rt73usb_write_beacon,
 	.get_tx_data_len	= rt73usb_get_tx_data_len,