+/**
+ * DOC: mac80211 software tx queueing
+ *
+ * mac80211 provides an optional intermediate queueing implementation designed
+ * to allow the driver to keep hardware queues short and provide some fairness
+ * between different stations/interfaces.
+ * In this model, the driver pulls data frames from the mac80211 queue instead
+ * of letting mac80211 push them via drv_tx().
+ * Other frames (e.g. control or management) are still pushed using drv_tx().
+ *
+ * Drivers indicate that they use this model by implementing the .wake_tx_queue
+ * driver operation.
+ *
+ * Intermediate queues (struct ieee80211_txq) are kept per-sta per-tid, with a
+ * single per-vif queue for multicast data frames.
+ *
+ * The driver is expected to initialize its private per-queue data for stations
+ * and interfaces in the .add_interface and .sta_add ops.
+ *
+ * The driver can't access the queue directly. To dequeue a frame, it calls
+ * ieee80211_tx_dequeue(). Whenever mac80211 adds a new frame to a queue, it
+ * calls the .wake_tx_queue driver op.
+ *
+ * For AP powersave TIM handling, the driver only needs to indicate if it has
+ * buffered packets in the driver specific data structures by calling
+ * ieee80211_sta_set_buffered(). For frames buffered in the ieee80211_txq
+ * struct, mac80211 sets the appropriate TIM PVB bits and calls
+ * .release_buffered_frames().
+ * In that callback the driver is therefore expected to release its own
+ * buffered frames and afterwards also frames from the ieee80211_txq (obtained
+ * via the usual ieee80211_tx_dequeue).
+ */
+