iwlwifi: A-MPDU Tx conform flows to mac80211

This patch alters the current iwlwifi behavior to fit the flows introduced
by the mac80211, mainly queues handling and start/stop call backs flows

Signed-off-by: Ron Rindjunsky <ron.rindjunsky@intel.com>
Signed-off-by: John W. Linville <linville@tuxdriver.com>

4 files changed, 302 insertions, 221 deletions

diff --git a/drivers/net/wireless/iwlwifi/iwl-4965-commands.h b/drivers/net/wireless/iwlwifi/iwl-4965-commands.h
index f3470c896d9a..9edd8abcf570 100644
--- a/drivers/net/wireless/iwlwifi/iwl-4965-commands.h
+++ b/drivers/net/wireless/iwlwifi/iwl-4965-commands.h
@@ -1300,6 +1300,25 @@ struct iwl4965_tx_resp {
         __le32 status;  /* TX status (for aggregation status of 1st frame) */
 } __attribute__ ((packed));
 
+struct agg_tx_status {
+        __le16 status;
+        __le16 sequence;
+} __attribute__ ((packed));
+
+struct iwl4965_tx_resp_agg {
+        u8 frame_count;         /* 1 no aggregation, >1 aggregation */
+        u8 reserved1;
+        u8 failure_rts;
+        u8 failure_frame;
+        __le32 rate_n_flags;
+        __le16 wireless_media_time;
+        __le16 reserved3;
+        __le32 pa_power1;
+        __le32 pa_power2;
+        struct agg_tx_status status;    /* TX status (for aggregation status */
+                                        /* of 1st frame) */
+} __attribute__ ((packed));
+
 /*
  * REPLY_COMPRESSED_BA = 0xc5 (response only, not a command)
  *
@@ -1313,9 +1332,8 @@ struct iwl4965_compressed_ba_resp {
         /* Index of recipient (BA-sending) station in uCode's station table */
         u8 sta_id;
         u8 tid;
-        __le16 ba_seq_ctl;
-        __le32 ba_bitmap0;
-        __le32 ba_bitmap1;
+        __le16 seq_ctl;
+        __le64 bitmap;
         __le16 scd_flow;
         __le16 scd_ssn;
 } __attribute__ ((packed));
diff --git a/drivers/net/wireless/iwlwifi/iwl-4965.c b/drivers/net/wireless/iwlwifi/iwl-4965.c
index 3fc18dc311e9..b315a099d1a0 100644
--- a/drivers/net/wireless/iwlwifi/iwl-4965.c
+++ b/drivers/net/wireless/iwlwifi/iwl-4965.c
@@ -79,6 +79,30 @@ const struct iwl4965_rate_info iwl4965_rates[IWL_RATE_COUNT] = {
         IWL_DECLARE_RATE_INFO(60, 60, 48, INV, 48, INV, 48, INV),/* 60mbps */
 };
 
+#ifdef CONFIG_IWL4965_HT
+
+static const u16 default_tid_to_tx_fifo[] = {
+        IWL_TX_FIFO_AC1,
+        IWL_TX_FIFO_AC0,
+        IWL_TX_FIFO_AC0,
+        IWL_TX_FIFO_AC1,
+        IWL_TX_FIFO_AC2,
+        IWL_TX_FIFO_AC2,
+        IWL_TX_FIFO_AC3,
+        IWL_TX_FIFO_AC3,
+        IWL_TX_FIFO_NONE,
+        IWL_TX_FIFO_NONE,
+        IWL_TX_FIFO_NONE,
+        IWL_TX_FIFO_NONE,
+        IWL_TX_FIFO_NONE,
+        IWL_TX_FIFO_NONE,
+        IWL_TX_FIFO_NONE,
+        IWL_TX_FIFO_NONE,
+        IWL_TX_FIFO_AC3
+};
+
+#endif  /*CONFIG_IWL4965_HT */
+
 static int is_fat_channel(__le32 rxon_flags)
 {
         return (rxon_flags & RXON_FLG_CHANNEL_MODE_PURE_40_MSK) ||
@@ -4185,6 +4209,7 @@ static void iwl4965_set_tx_status(struct iwl4965_priv *priv, int txq_id, int idx
         tx_status->control.tx_rate = rate;
 }
 
+#endif/* CONFIG_IWL4965_HT_AGG */
 
 /**
  * iwl4965_sta_modify_enable_tid_tx - Enable Tx for this TID in station table
@@ -4204,7 +4229,6 @@ static void iwl4965_sta_modify_enable_tid_tx(struct iwl4965_priv *priv,
         iwl4965_send_add_station(priv, &priv->stations[sta_id].sta, CMD_ASYNC);
 }
 
-
 /**
  * iwl4965_tx_status_reply_compressed_ba - Update tx status from block-ack
  *
@@ -4218,10 +4242,11 @@ static int iwl4965_tx_status_reply_compressed_ba(struct iwl4965_priv *priv,
 
 {
         int i, sh, ack;
-        u16 ba_seq_ctl = le16_to_cpu(ba_resp->ba_seq_ctl);
-        u32 bitmap0, bitmap1;
-        u32 resp_bitmap0 = le32_to_cpu(ba_resp->ba_bitmap0);
-        u32 resp_bitmap1 = le32_to_cpu(ba_resp->ba_bitmap1);
+        u16 seq_ctl = le16_to_cpu(ba_resp->seq_ctl);
+        u16 scd_flow = le16_to_cpu(ba_resp->scd_flow);
+        u64 bitmap;
+        int successes = 0;
+        struct ieee80211_tx_status *tx_status;
 
         if (unlikely(!agg->wait_for_ba))  {
                 IWL_ERROR("Received BA when not expected\n");
@@ -4230,17 +4255,15 @@ static int iwl4965_tx_status_reply_compressed_ba(struct iwl4965_priv *priv,
 
         /* Mark that the expected block-ack response arrived */
         agg->wait_for_ba = 0;
-        IWL_DEBUG_TX_REPLY("BA %d %d\n", agg->start_idx, ba_resp->ba_seq_ctl);
+        IWL_DEBUG_TX_REPLY("BA %d %d\n", agg->start_idx, ba_resp->seq_ctl);
 
         /* Calculate shift to align block-ack bits with our Tx window bits */
-        sh = agg->start_idx - SEQ_TO_INDEX(ba_seq_ctl >> 4);
+        sh = agg->start_idx - SEQ_TO_INDEX(seq_ctl>>4);
         if (sh < 0) /* tbw something is wrong with indices */
                 sh += 0x100;
 
         /* don't use 64-bit values for now */
-        bitmap0 = resp_bitmap0 >> sh;
-        bitmap1 = resp_bitmap1 >> sh;
-        bitmap0 |= (resp_bitmap1 & ((1 << sh) | ((1 << sh) - 1))) << (32 - sh);
+        bitmap = le64_to_cpu(ba_resp->bitmap) >> sh;
 
         if (agg->frame_count > (64 - sh)) {
                 IWL_DEBUG_TX_REPLY("more frames than bitmap size");
@@ -4249,23 +4272,106 @@ static int iwl4965_tx_status_reply_compressed_ba(struct iwl4965_priv *priv,
 
         /* check for success or failure according to the
          * transmitted bitmap and block-ack bitmap */
-        bitmap0 &= agg->bitmap0;
-        bitmap1 &= agg->bitmap1;
+        bitmap &= agg->bitmap;
 
         /* For each frame attempted in aggregation,
          * update driver's record of tx frame's status. */
         for (i = 0; i < agg->frame_count ; i++) {
-                int idx = (agg->start_idx + i) & 0xff;
-                ack = bitmap0 & (1 << i);
+                ack = bitmap & (1 << i);
+                successes += !!ack;
                 IWL_DEBUG_TX_REPLY("%s ON i=%d idx=%d raw=%d\n",
-                        ack? "ACK":"NACK", i, idx, agg->start_idx + i);
-                iwl4965_set_tx_status(priv, agg->txq_id, idx, ack, 0,
-                        agg->rate_n_flags);
+                        ack? "ACK":"NACK", i, (agg->start_idx + i) & 0xff,
+                        agg->start_idx + i);
+        }
+
+        tx_status = &priv->txq[scd_flow].txb[agg->start_idx].status;
+        tx_status->flags = IEEE80211_TX_STATUS_ACK;
+        tx_status->retry_count++;
+#ifdef CONFIG_IWL4965_HT_AGG
+        tx_status->flags |= IEEE80211_TX_STATUS_AGG_STATS;
+        tx_status->successes = successes;
+        tx_status->frame_count = agg->frame_count;
+#endif  /* CONFIG_IWL4965_HT_AGG */
+        tx_status->control.tx_rate = agg->rate_n_flags;
+
+        IWL_DEBUG_TX_REPLY("Bitmap %llx\n", bitmap);
+
+        return 0;
+}
+
+/**
+ * iwl4965_tx_queue_stop_scheduler - Stop queue, but keep configuration
+ */
+static void iwl4965_tx_queue_stop_scheduler(struct iwl4965_priv *priv,
+                                            u16 txq_id)
+{
+        /* Simply stop the queue, but don't change any configuration;
+         * the SCD_ACT_EN bit is the write-enable mask for the ACTIVE bit. */
+        iwl4965_write_prph(priv,
+                KDR_SCD_QUEUE_STATUS_BITS(txq_id),
+                (0 << SCD_QUEUE_STTS_REG_POS_ACTIVE)|
+                (1 << SCD_QUEUE_STTS_REG_POS_SCD_ACT_EN));
+}
 
+/**
+ * txq_id must be greater than IWL_BACK_QUEUE_FIRST_ID
+ */
+static int iwl4965_tx_queue_agg_disable(struct iwl4965_priv *priv, u16 txq_id,
+                                        u16 ssn_idx, u8 tx_fifo)
+{
+        if (IWL_BACK_QUEUE_FIRST_ID > txq_id) {
+                IWL_WARNING("queue number too small: %d, must be > %d\n",
+                                txq_id, IWL_BACK_QUEUE_FIRST_ID);
+                return -EINVAL;
         }
 
-        IWL_DEBUG_TX_REPLY("Bitmap %x%x\n", bitmap0, bitmap1);
+        iwl4965_tx_queue_stop_scheduler(priv, txq_id);
+
+        iwl4965_clear_bits_prph(priv, KDR_SCD_QUEUECHAIN_SEL, (1 << txq_id));
+
+        priv->txq[txq_id].q.read_ptr = (ssn_idx & 0xff);
+        priv->txq[txq_id].q.write_ptr = (ssn_idx & 0xff);
+        /* supposes that ssn_idx is valid (!= 0xFFF) */
+        iwl4965_set_wr_ptrs(priv, txq_id, ssn_idx);
+
+        iwl4965_clear_bits_prph(priv, KDR_SCD_INTERRUPT_MASK, (1 << txq_id));
+        iwl4965_txq_ctx_deactivate(priv, txq_id);
+        iwl4965_tx_queue_set_status(priv, &priv->txq[txq_id], tx_fifo, 0);
+
+        return 0;
+}
 
+int iwl4965_check_empty_hw_queue(struct iwl4965_priv *priv, int sta_id,
+                                         u8 tid, int txq_id)
+{
+        struct iwl4965_queue *q = &priv->txq[txq_id].q;
+        u8 *addr = priv->stations[sta_id].sta.sta.addr;
+        struct iwl4965_tid_data *tid_data = &priv->stations[sta_id].tid[tid];
+
+        switch (priv->stations[sta_id].tid[tid].agg.state) {
+        case IWL_EMPTYING_HW_QUEUE_DELBA:
+                /* We are reclaiming the last packet of the */
+                /* aggregated HW queue */
+                if (txq_id  == tid_data->agg.txq_id &&
+                    q->read_ptr == q->write_ptr) {
+                        u16 ssn = SEQ_TO_SN(tid_data->seq_number);
+                        int tx_fifo = default_tid_to_tx_fifo[tid];
+                        IWL_DEBUG_HT("HW queue empty: continue DELBA flow\n");
+                        iwl4965_tx_queue_agg_disable(priv, txq_id,
+                                                     ssn, tx_fifo);
+                        tid_data->agg.state = IWL_AGG_OFF;
+                        ieee80211_stop_tx_ba_cb_irqsafe(priv->hw, addr, tid);
+                }
+                break;
+        case IWL_EMPTYING_HW_QUEUE_ADDBA:
+                /* We are reclaiming the last packet of the queue */
+                if (tid_data->tfds_in_queue == 0) {
+                        IWL_DEBUG_HT("HW queue empty: continue ADDBA flow\n");
+                        tid_data->agg.state = IWL_AGG_ON;
+                        ieee80211_start_tx_ba_cb_irqsafe(priv->hw, addr, tid);
+                }
+                break;
+        }
         return 0;
 }
 
@@ -4293,48 +4399,43 @@ static void iwl4965_rx_reply_compressed_ba(struct iwl4965_priv *priv,
         int index;
         struct iwl4965_tx_queue *txq = NULL;
         struct iwl4965_ht_agg *agg;
+        DECLARE_MAC_BUF(mac);
 
         /* "flow" corresponds to Tx queue */
-        u16 ba_resp_scd_flow = le16_to_cpu(ba_resp->scd_flow);
+        u16 scd_flow = le16_to_cpu(ba_resp->scd_flow);
 
         /* "ssn" is start of block-ack Tx window, corresponds to index
          * (in Tx queue's circular buffer) of first TFD/frame in window */
         u16 ba_resp_scd_ssn = le16_to_cpu(ba_resp->scd_ssn);
 
-        if (ba_resp_scd_flow >= ARRAY_SIZE(priv->txq)) {
+        if (scd_flow >= ARRAY_SIZE(priv->txq)) {
                 IWL_ERROR("BUG_ON scd_flow is bigger than number of queues");
                 return;
         }
 
-        txq = &priv->txq[ba_resp_scd_flow];
+        txq = &priv->txq[scd_flow];
         agg = &priv->stations[ba_resp->sta_id].tid[ba_resp->tid].agg;
 
         /* Find index just before block-ack window */
         index = iwl4965_queue_dec_wrap(ba_resp_scd_ssn & 0xff, txq->q.n_bd);
 
         /* TODO: Need to get this copy more safely - now good for debug */
-/*
-        {
-        DECLARE_MAC_BUF(mac);
+
         IWL_DEBUG_TX_REPLY("REPLY_COMPRESSED_BA [%d]Received from %s, "
                            "sta_id = %d\n",
                            agg->wait_for_ba,
                            print_mac(mac, (u8*) &ba_resp->sta_addr_lo32),
                            ba_resp->sta_id);
-        IWL_DEBUG_TX_REPLY("TID = %d, SeqCtl = %d, bitmap = 0x%X%X, scd_flow = "
+        IWL_DEBUG_TX_REPLY("TID = %d, SeqCtl = %d, bitmap = 0x%llx, scd_flow = "
                            "%d, scd_ssn = %d\n",
                            ba_resp->tid,
-                           ba_resp->ba_seq_ctl,
-                           ba_resp->ba_bitmap1,
-                           ba_resp->ba_bitmap0,
+                           ba_resp->seq_ctl,
+                           ba_resp->bitmap,
                            ba_resp->scd_flow,
                            ba_resp->scd_ssn);
-        IWL_DEBUG_TX_REPLY("DAT start_idx = %d, bitmap = 0x%X%X \n",
+        IWL_DEBUG_TX_REPLY("DAT start_idx = %d, bitmap = 0x%llx \n",
                            agg->start_idx,
-                           agg->bitmap1,
-                           agg->bitmap0);
-        }
-*/
+                           agg->bitmap);
 
         /* Update driver's record of ACK vs. not for each frame in window */
         iwl4965_tx_status_reply_compressed_ba(priv, agg, ba_resp);
@@ -4342,23 +4443,17 @@ static void iwl4965_rx_reply_compressed_ba(struct iwl4965_priv *priv,
         /* Release all TFDs before the SSN, i.e. all TFDs in front of
          * block-ack window (we assume that they've been successfully
          * transmitted ... if not, it's too late anyway). */
-        if (txq->q.read_ptr != (ba_resp_scd_ssn & 0xff))
-                iwl4965_tx_queue_reclaim(priv, ba_resp_scd_flow, index);
-
-}
-
-
-/**
- * iwl4965_tx_queue_stop_scheduler - Stop queue, but keep configuration
- */
-static void iwl4965_tx_queue_stop_scheduler(struct iwl4965_priv *priv, u16 txq_id)
-{
-        /* Simply stop the queue, but don't change any configuration;
-         * the SCD_ACT_EN bit is the write-enable mask for the ACTIVE bit. */
-        iwl4965_write_prph(priv,
-                KDR_SCD_QUEUE_STATUS_BITS(txq_id),
-                (0 << SCD_QUEUE_STTS_REG_POS_ACTIVE)|
-                (1 << SCD_QUEUE_STTS_REG_POS_SCD_ACT_EN));
+        if (txq->q.read_ptr != (ba_resp_scd_ssn & 0xff)) {
+                int freed = iwl4965_tx_queue_reclaim(priv, scd_flow, index);
+                priv->stations[ba_resp->sta_id].
+                        tid[ba_resp->tid].tfds_in_queue -= freed;
+                if (iwl4965_queue_space(&txq->q) > txq->q.low_mark &&
+                        priv->mac80211_registered &&
+                        agg->state != IWL_EMPTYING_HW_QUEUE_DELBA)
+                        ieee80211_wake_queue(priv->hw, scd_flow);
+                iwl4965_check_empty_hw_queue(priv, ba_resp->sta_id,
+                        ba_resp->tid, scd_flow);
+        }
 }
 
 /**
@@ -4388,6 +4483,7 @@ static int iwl4965_tx_queue_set_q2ratid(struct iwl4965_priv *priv, u16 ra_tid,
         return 0;
 }
 
+
 /**
  * iwl4965_tx_queue_agg_enable - Set up & enable aggregation for selected queue
  *
@@ -4455,48 +4551,6 @@ static int iwl4965_tx_queue_agg_enable(struct iwl4965_priv *priv, int txq_id,
         return 0;
 }
 
-/**
- * txq_id must be greater than IWL_BACK_QUEUE_FIRST_ID
- */
-static int iwl4965_tx_queue_agg_disable(struct iwl4965_priv *priv, u16 txq_id,
-                                        u16 ssn_idx, u8 tx_fifo)
-{
-        unsigned long flags;
-        int rc;
-
-        if (IWL_BACK_QUEUE_FIRST_ID > txq_id) {
-                IWL_WARNING("queue number too small: %d, must be > %d\n",
-                                txq_id, IWL_BACK_QUEUE_FIRST_ID);
-                return -EINVAL;
-        }
-
-        spin_lock_irqsave(&priv->lock, flags);
-        rc = iwl4965_grab_nic_access(priv);
-        if (rc) {
-                spin_unlock_irqrestore(&priv->lock, flags);
-                return rc;
-        }
-
-        iwl4965_tx_queue_stop_scheduler(priv, txq_id);
-
-        iwl4965_clear_bits_prph(priv, KDR_SCD_QUEUECHAIN_SEL, (1 << txq_id));
-
-        priv->txq[txq_id].q.read_ptr = (ssn_idx & 0xff);
-        priv->txq[txq_id].q.write_ptr = (ssn_idx & 0xff);
-        /* supposes that ssn_idx is valid (!= 0xFFF) */
-        iwl4965_set_wr_ptrs(priv, txq_id, ssn_idx);
-
-        iwl4965_clear_bits_prph(priv, KDR_SCD_INTERRUPT_MASK, (1 << txq_id));
-        iwl4965_txq_ctx_deactivate(priv, txq_id);
-        iwl4965_tx_queue_set_status(priv, &priv->txq[txq_id], tx_fifo, 0);
-
-        iwl4965_release_nic_access(priv);
-        spin_unlock_irqrestore(&priv->lock, flags);
-
-        return 0;
-}
-
-#endif/* CONFIG_IWL4965_HT_AGG */
 #endif /* CONFIG_IWL4965_HT */
 
 /**
@@ -4730,28 +4784,6 @@ static void iwl4965_sta_modify_del_ba_tid(struct iwl4965_priv *priv,
         iwl4965_send_add_station(priv, &priv->stations[sta_id].sta, CMD_ASYNC);
 }
 
-#ifdef CONFIG_IWL4965_HT_AGG
-
-static const u16 default_tid_to_tx_fifo[] = {
-        IWL_TX_FIFO_AC1,
-        IWL_TX_FIFO_AC0,
-        IWL_TX_FIFO_AC0,
-        IWL_TX_FIFO_AC1,
-        IWL_TX_FIFO_AC2,
-        IWL_TX_FIFO_AC2,
-        IWL_TX_FIFO_AC3,
-        IWL_TX_FIFO_AC3,
-        IWL_TX_FIFO_NONE,
-        IWL_TX_FIFO_NONE,
-        IWL_TX_FIFO_NONE,
-        IWL_TX_FIFO_NONE,
-        IWL_TX_FIFO_NONE,
-        IWL_TX_FIFO_NONE,
-        IWL_TX_FIFO_NONE,
-        IWL_TX_FIFO_NONE,
-        IWL_TX_FIFO_AC3
-};
-
 /*
  * Find first available (lowest unused) Tx Queue, mark it "active".
  * Called only when finding queue for aggregation.
@@ -4768,69 +4800,78 @@ static int iwl4965_txq_ctx_activate_free(struct iwl4965_priv *priv)
         return -1;
 }
 
-int iwl4965_mac_ht_tx_agg_start(struct ieee80211_hw *hw, u8 *da, u16 tid,
-                            u16 *start_seq_num)
+static int iwl4965_mac_ht_tx_agg_start(struct ieee80211_hw *hw, const u8 *da,
+                                       u16 tid, u16 *start_seq_num)
 {
-
         struct iwl4965_priv *priv = hw->priv;
         int sta_id;
         int tx_fifo;
         int txq_id;
         int ssn = -1;
+        int rc = 0;
         unsigned long flags;
         struct iwl4965_tid_data *tid_data;
         DECLARE_MAC_BUF(mac);
 
-        /* Determine Tx DMA/FIFO channel for this Traffic ID */
         if (likely(tid < ARRAY_SIZE(default_tid_to_tx_fifo)))
                 tx_fifo = default_tid_to_tx_fifo[tid];
         else
                 return -EINVAL;
 
-        IWL_WARNING("iwl-AGG iwl4965_mac_ht_tx_agg_start on da=%s"
-                    " tid=%d\n", print_mac(mac, da), tid);
+        IWL_WARNING("%s on da = %s tid = %d\n",
+                        __func__, print_mac(mac, da), tid);
 
-        /* Get index into station table */
         sta_id = iwl4965_hw_find_station(priv, da);
         if (sta_id == IWL_INVALID_STATION)
                 return -ENXIO;
 
-        /* Find available Tx queue for aggregation */
+        if (priv->stations[sta_id].tid[tid].agg.state != IWL_AGG_OFF) {
+                IWL_ERROR("Start AGG when state is not IWL_AGG_OFF !\n");
+                return -ENXIO;
+        }
+
         txq_id = iwl4965_txq_ctx_activate_free(priv);
         if (txq_id == -1)
                 return -ENXIO;
 
         spin_lock_irqsave(&priv->sta_lock, flags);
         tid_data = &priv->stations[sta_id].tid[tid];
-
-        /* Get starting sequence number for 1st frame in block ack window.
-         * We'll use least signif byte as 1st frame's index into Tx queue. */
         ssn = SEQ_TO_SN(tid_data->seq_number);
         tid_data->agg.txq_id = txq_id;
         spin_unlock_irqrestore(&priv->sta_lock, flags);
 
         *start_seq_num = ssn;
-
-        /* Update driver's link quality manager */
-        iwl4965_ba_status(priv, tid, BA_STATUS_ACTIVE);
-
-        /* Set up and enable aggregation for selected Tx queue and FIFO */
-        return iwl4965_tx_queue_agg_enable(priv, txq_id, tx_fifo,
+        rc = iwl4965_tx_queue_agg_enable(priv, txq_id, tx_fifo,
                                            sta_id, tid, ssn);
-}
+        if (rc)
+                return rc;
 
+        rc = 0;
+        if (tid_data->tfds_in_queue == 0) {
+                printk(KERN_ERR "HW queue is empty\n");
+                tid_data->agg.state = IWL_AGG_ON;
+                ieee80211_start_tx_ba_cb_irqsafe(hw, da, tid);
+        } else {
+                IWL_DEBUG_HT("HW queue is NOT empty: %d packets in HW queue\n",
+                                tid_data->tfds_in_queue);
+                tid_data->agg.state = IWL_EMPTYING_HW_QUEUE_ADDBA;
+        }
+        return rc;
+}
 
-int iwl4965_mac_ht_tx_agg_stop(struct ieee80211_hw *hw, u8 *da, u16 tid)
+static int iwl4965_mac_ht_tx_agg_stop(struct ieee80211_hw *hw, const u8 *da,
+                                      u16 tid)
 {
 
         struct iwl4965_priv *priv = hw->priv;
         int tx_fifo_id, txq_id, sta_id, ssn = -1;
         struct iwl4965_tid_data *tid_data;
-        int rc;
+        int rc, write_ptr, read_ptr;
+        unsigned long flags;
         DECLARE_MAC_BUF(mac);
 
         if (!da) {
-                IWL_ERROR("%s: da = NULL\n", __func__);
+                IWL_ERROR("da = NULL\n");
                 return -EINVAL;
         }
 
@@ -4844,33 +4885,44 @@ int iwl4965_mac_ht_tx_agg_stop(struct ieee80211_hw *hw, u8 *da, u16 tid)
         if (sta_id == IWL_INVALID_STATION)
                 return -ENXIO;
 
+        if (priv->stations[sta_id].tid[tid].agg.state != IWL_AGG_ON)
+                IWL_WARNING("Stopping AGG while state not IWL_AGG_ON\n");
+
         tid_data = &priv->stations[sta_id].tid[tid];
         ssn = (tid_data->seq_number & IEEE80211_SCTL_SEQ) >> 4;
         txq_id = tid_data->agg.txq_id;
+        write_ptr = priv->txq[txq_id].q.write_ptr;
+        read_ptr = priv->txq[txq_id].q.read_ptr;
+
+        /* The queue is not empty */
+        if (write_ptr != read_ptr) {
+                IWL_DEBUG_HT("Stopping a non empty AGG HW QUEUE\n");
+                priv->stations[sta_id].tid[tid].agg.state =
+                                IWL_EMPTYING_HW_QUEUE_DELBA;
+                return 0;
+        }
+
+        IWL_DEBUG_HT("HW queue empty\n");;
+        priv->stations[sta_id].tid[tid].agg.state = IWL_AGG_OFF;
 
+        spin_lock_irqsave(&priv->lock, flags);
+        rc = iwl4965_grab_nic_access(priv);
+        if (rc) {
+                spin_unlock_irqrestore(&priv->lock, flags);
+                return rc;
+        }
         rc = iwl4965_tx_queue_agg_disable(priv, txq_id, ssn, tx_fifo_id);
-        /* FIXME: need more safe way to handle error condition */
+        iwl4965_release_nic_access(priv);
+        spin_unlock_irqrestore(&priv->lock, flags);
+
         if (rc)
                 return rc;
 
-        iwl4965_ba_status(priv, tid, BA_STATUS_INITIATOR_DELBA);
-        IWL_DEBUG_INFO("iwl4965_mac_ht_tx_agg_stop on da=%s tid=%d\n",
-                       print_mac(mac, da), tid);
+        ieee80211_stop_tx_ba_cb_irqsafe(priv->hw, da, tid);
 
-        return 0;
-}
-
-
-#endif /* CONFIG_IWL4965_HT_AGG */
-
-int iwl4965_mac_ht_tx_agg_start(struct ieee80211_hw *hw, const u8 *da, u16 tid,
-                                u16 *start_seq_num)
-{
-        return 0;
-}
+        IWL_DEBUG_INFO("iwl4965_mac_ht_tx_agg_stop on da=%s tid=%d\n",
+                        print_mac(mac, da), tid);
 
-int iwl4965_mac_ht_tx_agg_stop(struct ieee80211_hw *hw, const u8 *da, u16 tid)
-{
         return 0;
 }
 
@@ -4924,9 +4976,7 @@ void iwl4965_hw_rx_handler_setup(struct iwl4965_priv *priv)
             iwl4965_rx_missed_beacon_notif;
 
 #ifdef CONFIG_IWL4965_HT
-#ifdef CONFIG_IWL4965_HT_AGG
         priv->rx_handlers[REPLY_COMPRESSED_BA] = iwl4965_rx_reply_compressed_ba;
-#endif /* CONFIG_IWL4965_HT_AGG */
 #endif /* CONFIG_IWL4965_HT */
 }
 
diff --git a/drivers/net/wireless/iwlwifi/iwl-4965.h b/drivers/net/wireless/iwlwifi/iwl-4965.h
index 4992b8a06367..47c7f3ffe369 100644
--- a/drivers/net/wireless/iwlwifi/iwl-4965.h
+++ b/drivers/net/wireless/iwlwifi/iwl-4965.h
@@ -433,7 +433,6 @@ struct iwl4965_rx_queue {
 #define IWL_INVALID_VALUE    -1
 
 #ifdef CONFIG_IWL4965_HT
-#ifdef CONFIG_IWL4965_HT_AGG
 /**
  * struct iwl4965_ht_agg -- aggregation status while waiting for block-ack
  * @txq_id: Tx queue used for Tx attempt
@@ -453,19 +452,22 @@ struct iwl4965_ht_agg {
         u16 frame_count;
         u16 wait_for_ba;
         u16 start_idx;
-        u32 bitmap0;
-        u32 bitmap1;
+        u64 bitmap;
         u32 rate_n_flags;
+#define IWL_AGG_OFF 0
+#define IWL_AGG_ON 1
+#define IWL_EMPTYING_HW_QUEUE_ADDBA 2
+#define IWL_EMPTYING_HW_QUEUE_DELBA 3
+        u8 state;
 };
-#endif /* CONFIG_IWL4965_HT_AGG */
+
 #endif /* CONFIG_IWL4965_HT */
 
 struct iwl4965_tid_data {
         u16 seq_number;
+        u16 tfds_in_queue;
 #ifdef CONFIG_IWL4965_HT
-#ifdef CONFIG_IWL4965_HT_AGG
         struct iwl4965_ht_agg agg;
-#endif  /* CONFIG_IWL4965_HT_AGG */
 #endif /* CONFIG_IWL4965_HT */
 };
 
@@ -743,7 +745,7 @@ extern u8 iwl4965_hw_find_station(struct iwl4965_priv *priv, const u8 *bssid);
 
 extern int iwl4965_hw_channel_switch(struct iwl4965_priv *priv, u16 channel);
 extern int iwl4965_tx_queue_reclaim(struct iwl4965_priv *priv, int txq_id, int index);
-
+extern int iwl4965_queue_space(const struct iwl4965_queue *q);
 struct iwl4965_priv;
 
 /*
@@ -778,6 +780,8 @@ extern void iwl4965_set_ht_add_station(struct iwl4965_priv *priv, u8 index,
 extern int iwl4965_mac_ampdu_action(struct ieee80211_hw *hw,
                                     enum ieee80211_ampdu_mlme_action action,
                                     const u8 *addr, u16 tid, u16 *ssn);
+extern int iwl4965_check_empty_hw_queue(struct iwl4965_priv *priv, int sta_id,
+                                        u8 tid, int txq_id);
 #ifdef CONFIG_IWL4965_HT_AGG
 extern void iwl4965_turn_off_agg(struct iwl4965_priv *priv, u8 tid);
 extern void iwl4965_tl_get_stats(struct iwl4965_priv *priv,
@@ -855,7 +859,7 @@ struct iwl4965_agg_control {
         u32 ba_timeout;
         struct iwl4965_traffic_load traffic_load[TID_MAX_LOAD_COUNT];
 };
-#endif                          /*CONFIG_IWL4965_HT_AGG */
+#endif /*CONFIG_IWL4965_HT_AGG */
 
 struct iwl4965_lq_mngr {
 #ifdef CONFIG_IWL4965_HT_AGG
diff --git a/drivers/net/wireless/iwlwifi/iwl4965-base.c b/drivers/net/wireless/iwlwifi/iwl4965-base.c
index 3f5114f5fe16..16cb990e06fa 100644
--- a/drivers/net/wireless/iwlwifi/iwl4965-base.c
+++ b/drivers/net/wireless/iwlwifi/iwl4965-base.c
@@ -205,7 +205,7 @@ static void iwl4965_print_hex_dump(int level, void *p, u32 len)
  * See more detailed info in iwl-4965-hw.h.
  ***************************************************/
 
-static int iwl4965_queue_space(const struct iwl4965_queue *q)
+int iwl4965_queue_space(const struct iwl4965_queue *q)
 {
         int s = q->read_ptr - q->write_ptr;
 
@@ -2972,11 +2972,10 @@ static int iwl4965_tx_skb(struct iwl4965_priv *priv,
                                 __constant_cpu_to_le16(IEEE80211_SCTL_FRAG));
                 seq_number += 0x10;
 #ifdef CONFIG_IWL4965_HT
-#ifdef CONFIG_IWL4965_HT_AGG
                 /* aggregation is on for this <sta,tid> */
-                if (ctl->flags & IEEE80211_TXCTL_HT_MPDU_AGG)
+                if (ctl->flags & IEEE80211_TXCTL_AMPDU)
                         txq_id = priv->stations[sta_id].tid[tid].agg.txq_id;
-#endif /* CONFIG_IWL4965_HT_AGG */
+                priv->stations[sta_id].tid[tid].tfds_in_queue++;
 #endif /* CONFIG_IWL4965_HT */
         }
 
@@ -3528,10 +3527,10 @@ int iwl4965_tx_queue_reclaim(struct iwl4965_priv *priv, int txq_id, int index)
                 nfreed++;
         }
 
-        if (iwl4965_queue_space(q) > q->low_mark && (txq_id >= 0) &&
+/*      if (iwl4965_queue_space(q) > q->low_mark && (txq_id >= 0) &&
                         (txq_id != IWL_CMD_QUEUE_NUM) &&
                         priv->mac80211_registered)
-                ieee80211_wake_queue(priv->hw, txq_id);
+                ieee80211_wake_queue(priv->hw, txq_id); */
 
 
         return nfreed;
@@ -3550,7 +3549,6 @@ static int iwl4965_is_tx_success(u32 status)
  *
  ******************************************************************************/
 #ifdef CONFIG_IWL4965_HT
-#ifdef CONFIG_IWL4965_HT_AGG
 
 static inline int iwl4965_get_ra_sta_id(struct iwl4965_priv *priv,
                                     struct ieee80211_hdr *hdr)
@@ -3585,11 +3583,11 @@ static inline u32 iwl4965_get_scd_ssn(struct iwl4965_tx_resp *tx_resp)
  */
 static int iwl4965_tx_status_reply_tx(struct iwl4965_priv *priv,
                                       struct iwl4965_ht_agg *agg,
-                                      struct iwl4965_tx_resp *tx_resp,
+                                      struct iwl4965_tx_resp_agg *tx_resp,
                                       u16 start_idx)
 {
-        u32 status;
-        __le32 *frame_status = &tx_resp->status;
+        u16 status;
+        struct agg_tx_status *frame_status = &tx_resp->status;
         struct ieee80211_tx_status *tx_status = NULL;
         struct ieee80211_hdr *hdr = NULL;
         int i, sh;
@@ -3602,26 +3600,25 @@ static int iwl4965_tx_status_reply_tx(struct iwl4965_priv *priv,
         agg->frame_count = tx_resp->frame_count;
         agg->start_idx = start_idx;
         agg->rate_n_flags = le32_to_cpu(tx_resp->rate_n_flags);
-        agg->bitmap0 = agg->bitmap1 = 0;
+        agg->bitmap = 0;
 
         /* # frames attempted by Tx command */
         if (agg->frame_count == 1) {
                 /* Only one frame was attempted; no block-ack will arrive */
-                struct iwl4965_tx_queue *txq ;
-                status = le32_to_cpu(frame_status[0]);
+                status = le16_to_cpu(frame_status[0].status);
+                seq  = le16_to_cpu(frame_status[0].sequence);
+                idx = SEQ_TO_INDEX(seq);
+                txq_id = SEQ_TO_QUEUE(seq);
 
-                txq_id = agg->txq_id;
-                txq = &priv->txq[txq_id];
                 /* FIXME: code repetition */
-                IWL_DEBUG_TX_REPLY("FrameCnt = %d, StartIdx=%d \n",
-                                   agg->frame_count, agg->start_idx);
+                IWL_DEBUG_TX_REPLY("FrameCnt = %d, StartIdx=%d idx=%d\n",
+                                   agg->frame_count, agg->start_idx, idx);
 
-                tx_status = &(priv->txq[txq_id].txb[txq->q.read_ptr].status);
+                tx_status = &(priv->txq[txq_id].txb[idx].status);
                 tx_status->retry_count = tx_resp->failure_frame;
                 tx_status->queue_number = status & 0xff;
-                tx_status->queue_length = tx_resp->bt_kill_count;
-                tx_status->queue_length |= tx_resp->failure_rts;
-
+                tx_status->queue_length = tx_resp->failure_rts;
+                tx_status->control.flags &= ~IEEE80211_TXCTL_AMPDU;
                 tx_status->flags = iwl4965_is_tx_success(status)?
                         IEEE80211_TX_STATUS_ACK : 0;
                 tx_status->control.tx_rate =
@@ -3642,8 +3639,8 @@ static int iwl4965_tx_status_reply_tx(struct iwl4965_priv *priv,
                 /* Construct bit-map of pending frames within Tx window */
                 for (i = 0; i < agg->frame_count; i++) {
                         u16 sc;
-                        status = le32_to_cpu(frame_status[i]);
-                        seq  = status >> 16;
+                        status = le16_to_cpu(frame_status[i].status);
+                        seq  = le16_to_cpu(frame_status[i].sequence);
                         idx = SEQ_TO_INDEX(seq);
                         txq_id = SEQ_TO_QUEUE(seq);
 
@@ -3687,13 +3684,12 @@ static int iwl4965_tx_status_reply_tx(struct iwl4965_priv *priv,
                                            start, (u32)(bitmap & 0xFFFFFFFF));
                 }
 
-                agg->bitmap0 = bitmap & 0xFFFFFFFF;
-                agg->bitmap1 = bitmap >> 32;
+                agg->bitmap = bitmap;
                 agg->start_idx = start;
                 agg->rate_n_flags = le32_to_cpu(tx_resp->rate_n_flags);
-                IWL_DEBUG_TX_REPLY("Frames %d start_idx=%d bitmap=0x%x\n",
+                IWL_DEBUG_TX_REPLY("Frames %d start_idx=%d bitmap=0x%llx\n",
                                    agg->frame_count, agg->start_idx,
-                                   agg->bitmap0);
+                                   agg->bitmap);
 
                 if (bitmap)
                         agg->wait_for_ba = 1;
@@ -3701,7 +3697,6 @@ static int iwl4965_tx_status_reply_tx(struct iwl4965_priv *priv,
         return 0;
 }
 #endif
-#endif
 
 /**
  * iwl4965_rx_reply_tx - Handle standard (non-aggregation) Tx response
@@ -3718,9 +3713,9 @@ static void iwl4965_rx_reply_tx(struct iwl4965_priv *priv,
         struct iwl4965_tx_resp *tx_resp = (void *)&pkt->u.raw[0];
         u32  status = le32_to_cpu(tx_resp->status);
 #ifdef CONFIG_IWL4965_HT
-#ifdef CONFIG_IWL4965_HT_AGG
-        int tid, sta_id;
-#endif
+        int tid = MAX_TID_COUNT, sta_id = IWL_INVALID_STATION;
+        struct ieee80211_hdr *hdr;
+        __le16 *qc;
 #endif
 
         if ((index >= txq->q.n_bd) || (x2_queue_used(&txq->q, index) == 0)) {
@@ -3732,44 +3727,51 @@ static void iwl4965_rx_reply_tx(struct iwl4965_priv *priv,
         }
 
 #ifdef CONFIG_IWL4965_HT
-#ifdef CONFIG_IWL4965_HT_AGG
+        hdr = iwl4965_tx_queue_get_hdr(priv, txq_id, index);
+        qc = ieee80211_get_qos_ctrl(hdr);
+
+        if (qc)
+                tid = le16_to_cpu(*qc) & 0xf;
+
+        sta_id = iwl4965_get_ra_sta_id(priv, hdr);
+        if (txq->sched_retry && unlikely(sta_id == IWL_INVALID_STATION)) {
+                IWL_ERROR("Station not known\n");
+                return;
+        }
+
         if (txq->sched_retry) {
                 const u32 scd_ssn = iwl4965_get_scd_ssn(tx_resp);
-                struct ieee80211_hdr *hdr =
-                        iwl4965_tx_queue_get_hdr(priv, txq_id, index);
                 struct iwl4965_ht_agg *agg = NULL;
-                __le16 *qc = ieee80211_get_qos_ctrl(hdr);
 
-                if (qc == NULL) {
-                        IWL_ERROR("BUG_ON qc is null!!!!\n");
+                if (!qc)
                         return;
-                }
-
-                tid = le16_to_cpu(*qc) & 0xf;
-
-                sta_id = iwl4965_get_ra_sta_id(priv, hdr);
-                if (unlikely(sta_id == IWL_INVALID_STATION)) {
-                        IWL_ERROR("Station not known for\n");
-                        return;
-                }
 
                 agg = &priv->stations[sta_id].tid[tid].agg;
 
-                iwl4965_tx_status_reply_tx(priv, agg, tx_resp, index);
+                iwl4965_tx_status_reply_tx(priv, agg,
+                                (struct iwl4965_tx_resp_agg *)tx_resp, index);
 
                 if ((tx_resp->frame_count == 1) &&
                     !iwl4965_is_tx_success(status)) {
                         /* TODO: send BAR */
                 }
 
-                if ((txq->q.read_ptr != (scd_ssn & 0xff))) {
+                if (txq->q.read_ptr != (scd_ssn & 0xff)) {
+                        int freed;
                         index = iwl4965_queue_dec_wrap(scd_ssn & 0xff, txq->q.n_bd);
                         IWL_DEBUG_TX_REPLY("Retry scheduler reclaim scd_ssn "
                                            "%d index %d\n", scd_ssn , index);
-                        iwl4965_tx_queue_reclaim(priv, txq_id, index);
+                        freed = iwl4965_tx_queue_reclaim(priv, txq_id, index);
+                        priv->stations[sta_id].tid[tid].tfds_in_queue -= freed;
+
+                        if (iwl4965_queue_space(&txq->q) > txq->q.low_mark &&
+                            txq_id >= 0 && priv->mac80211_registered &&
+                            agg->state != IWL_EMPTYING_HW_QUEUE_DELBA)
+                                ieee80211_wake_queue(priv->hw, txq_id);
+
+                        iwl4965_check_empty_hw_queue(priv, sta_id, tid, txq_id);
                 }
         } else {
-#endif /* CONFIG_IWL4965_HT_AGG */
 #endif /* CONFIG_IWL4965_HT */
         tx_status = &(txq->txb[txq->q.read_ptr].status);
 
@@ -3790,12 +3792,21 @@ static void iwl4965_rx_reply_tx(struct iwl4965_priv *priv,
                      tx_resp->failure_frame);
 
         IWL_DEBUG_TX_REPLY("Tx queue reclaim %d\n", index);
-        if (index != -1)
-                iwl4965_tx_queue_reclaim(priv, txq_id, index);
+        if (index != -1) {
+                int freed = iwl4965_tx_queue_reclaim(priv, txq_id, index);
+#ifdef CONFIG_IWL4965_HT
+                if (tid != MAX_TID_COUNT)
+                        priv->stations[sta_id].tid[tid].tfds_in_queue -= freed;
+                if (iwl4965_queue_space(&txq->q) > txq->q.low_mark &&
+                        (txq_id >= 0) &&
+                        priv->mac80211_registered)
+                        ieee80211_wake_queue(priv->hw, txq_id);
+                if (tid != MAX_TID_COUNT)
+                        iwl4965_check_empty_hw_queue(priv, sta_id, tid, txq_id);
+#endif
+        }
 #ifdef CONFIG_IWL4965_HT
-#ifdef CONFIG_IWL4965_HT_AGG
         }
-#endif /* CONFIG_IWL4965_HT_AGG */
 #endif /* CONFIG_IWL4965_HT */
 
         if (iwl_check_bits(status, TX_ABORT_REQUIRED_MSK))
@@ -9089,10 +9100,8 @@ static int iwl4965_pci_probe(struct pci_dev *pdev, const struct pci_device_id *e
         /* Default value; 4 EDCA QOS priorities */
         hw->queues = 4;
 #ifdef CONFIG_IWL4965_HT
-#ifdef CONFIG_IWL4965_HT_AGG
         /* Enhanced value; more queues, to support 11n aggregation */
         hw->queues = 16;
-#endif /* CONFIG_IWL4965_HT_AGG */
 #endif /* CONFIG_IWL4965_HT */
 
         spin_lock_init(&priv->lock);