OSCL-LXR linux-6.0.1/​drivers/​net/​wireless/​ath/​carl9170/​tx.c	Source navigation Diff markup Identifier search General search
	Version: linux-6.0.1 spark-3.0.0 hadoop-3.2.0-src hadoop-3.3.0-src spark-2.4.7 linux-4.15.13 hadoop-2.7.4-src Revert   Change

 /*
  * Atheros CARL9170 driver
  *
  * 802.11 xmit & status routines
  *
  * Copyright 2008, Johannes Berg <johannes@sipsolutions.net>
  * Copyright 2009, 2010, Christian Lamparter <chunkeey@googlemail.com>
  *
  * This program is free software; you can redistribute it and/or modify
  * it under the terms of the GNU General Public License as published by
  * the Free Software Foundation; either version 2 of the License, or
  * (at your option) any later version.
  *
  * This program is distributed in the hope that it will be useful,
  * but WITHOUT ANY WARRANTY; without even the implied warranty of
  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  * GNU General Public License for more details.
  *
  * You should have received a copy of the GNU General Public License
  * along with this program; see the file COPYING.  If not, see
  * http://www.gnu.org/licenses/.
  *
  * This file incorporates work covered by the following copyright and
  * permission notice:
  *    Copyright (c) 2007-2008 Atheros Communications, Inc.
  *
  *    Permission to use, copy, modify, and/or distribute this software for any
  *    purpose with or without fee is hereby granted, provided that the above
  *    copyright notice and this permission notice appear in all copies.
  *
  *    THE SOFTWARE IS PROVIDED "AS IS" AND THE AUTHOR DISCLAIMS ALL WARRANTIES
  *    WITH REGARD TO THIS SOFTWARE INCLUDING ALL IMPLIED WARRANTIES OF
  *    MERCHANTABILITY AND FITNESS. IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR
  *    ANY SPECIAL, DIRECT, INDIRECT, OR CONSEQUENTIAL DAMAGES OR ANY DAMAGES
  *    WHATSOEVER RESULTING FROM LOSS OF USE, DATA OR PROFITS, WHETHER IN AN
  *    ACTION OF CONTRACT, NEGLIGENCE OR OTHER TORTIOUS ACTION, ARISING OUT OF
  *    OR IN CONNECTION WITH THE USE OR PERFORMANCE OF THIS SOFTWARE.
  */
 
 #include <linux/slab.h>
 #include <linux/module.h>
 #include <linux/etherdevice.h>
 #include <net/mac80211.h>
 #include "carl9170.h"
 #include "hw.h"
 #include "cmd.h"
 
 static inline unsigned int __carl9170_get_queue(struct ar9170 *ar,
                         unsigned int queue)
 {
     if (unlikely(modparam_noht)) {
         return queue;
     } else {
         /*
          * This is just another workaround, until
          * someone figures out how to get QoS and
          * AMPDU to play nicely together.
          */
 
         return 2;       /* AC_BE */
     }
 }
 
 static inline unsigned int carl9170_get_queue(struct ar9170 *ar,
                           struct sk_buff *skb)
 {
     return __carl9170_get_queue(ar, skb_get_queue_mapping(skb));
 }
 
 static bool is_mem_full(struct ar9170 *ar)
 {
     return (DIV_ROUND_UP(IEEE80211_MAX_FRAME_LEN, ar->fw.mem_block_size) >
         atomic_read(&ar->mem_free_blocks));
 }
 
 static void carl9170_tx_accounting(struct ar9170 *ar, struct sk_buff *skb)
 {
     int queue, i;
     bool mem_full;
 
     atomic_inc(&ar->tx_total_queued);
 
     queue = skb_get_queue_mapping(skb);
     spin_lock_bh(&ar->tx_stats_lock);
 
     /*
      * The driver has to accept the frame, regardless if the queue is
      * full to the brim, or not. We have to do the queuing internally,
      * since mac80211 assumes that a driver which can operate with
      * aggregated frames does not reject frames for this reason.
      */
     ar->tx_stats[queue].len++;
     ar->tx_stats[queue].count++;
 
     mem_full = is_mem_full(ar);
     for (i = 0; i < ar->hw->queues; i++) {
         if (mem_full || ar->tx_stats[i].len >= ar->tx_stats[i].limit) {
             ieee80211_stop_queue(ar->hw, i);
             ar->queue_stop_timeout[i] = jiffies;
         }
     }
 
     spin_unlock_bh(&ar->tx_stats_lock);
 }
 
 /* needs rcu_read_lock */
 static struct ieee80211_sta *__carl9170_get_tx_sta(struct ar9170 *ar,
                            struct sk_buff *skb)
 {
     struct _carl9170_tx_superframe *super = (void *) skb->data;
     struct ieee80211_hdr *hdr = (void *) super->frame_data;
     struct ieee80211_vif *vif;
     unsigned int vif_id;
 
     vif_id = (super->s.misc & CARL9170_TX_SUPER_MISC_VIF_ID) >>
          CARL9170_TX_SUPER_MISC_VIF_ID_S;
 
     if (WARN_ON_ONCE(vif_id >= AR9170_MAX_VIRTUAL_MAC))
         return NULL;
 
     vif = rcu_dereference(ar->vif_priv[vif_id].vif);
     if (unlikely(!vif))
         return NULL;
 
     /*
      * Normally we should use wrappers like ieee80211_get_DA to get
      * the correct peer ieee80211_sta.
      *
      * But there is a problem with indirect traffic (broadcasts, or
      * data which is designated for other stations) in station mode.
      * The frame will be directed to the AP for distribution and not
      * to the actual destination.
      */
 
     return ieee80211_find_sta(vif, hdr->addr1);
 }
 
 static void carl9170_tx_ps_unblock(struct ar9170 *ar, struct sk_buff *skb)
 {
     struct ieee80211_sta *sta;
     struct carl9170_sta_info *sta_info;
 
     rcu_read_lock();
     sta = __carl9170_get_tx_sta(ar, skb);
     if (unlikely(!sta))
         goto out_rcu;
 
     sta_info = (struct carl9170_sta_info *) sta->drv_priv;
     if (atomic_dec_return(&sta_info->pending_frames) == 0)
         ieee80211_sta_block_awake(ar->hw, sta, false);
 
 out_rcu:
     rcu_read_unlock();
 }
 
 static void carl9170_tx_accounting_free(struct ar9170 *ar, struct sk_buff *skb)
 {
     int queue;
 
     queue = skb_get_queue_mapping(skb);
 
     spin_lock_bh(&ar->tx_stats_lock);
 
     ar->tx_stats[queue].len--;
 
     if (!is_mem_full(ar)) {
         unsigned int i;
         for (i = 0; i < ar->hw->queues; i++) {
             if (ar->tx_stats[i].len >= CARL9170_NUM_TX_LIMIT_SOFT)
                 continue;
 
             if (ieee80211_queue_stopped(ar->hw, i)) {
                 unsigned long tmp;
 
                 tmp = jiffies - ar->queue_stop_timeout[i];
                 if (tmp > ar->max_queue_stop_timeout[i])
                     ar->max_queue_stop_timeout[i] = tmp;
             }
 
             ieee80211_wake_queue(ar->hw, i);
         }
     }
 
     spin_unlock_bh(&ar->tx_stats_lock);
 
     if (atomic_dec_and_test(&ar->tx_total_queued))
         complete(&ar->tx_flush);
 }
 
 static int carl9170_alloc_dev_space(struct ar9170 *ar, struct sk_buff *skb)
 {
     struct _carl9170_tx_superframe *super = (void *) skb->data;
     unsigned int chunks;
     int cookie = -1;
 
     atomic_inc(&ar->mem_allocs);
 
     chunks = DIV_ROUND_UP(skb->len, ar->fw.mem_block_size);
     if (unlikely(atomic_sub_return(chunks, &ar->mem_free_blocks) < 0)) {
         atomic_add(chunks, &ar->mem_free_blocks);
         return -ENOSPC;
     }
 
     spin_lock_bh(&ar->mem_lock);
     cookie = bitmap_find_free_region(ar->mem_bitmap, ar->fw.mem_blocks, 0);
     spin_unlock_bh(&ar->mem_lock);
 
     if (unlikely(cookie < 0)) {
         atomic_add(chunks, &ar->mem_free_blocks);
         return -ENOSPC;
     }
 
     super = (void *) skb->data;
 
     /*
      * Cookie #0 serves two special purposes:
      *  1. The firmware might use it generate BlockACK frames
      *     in responds of an incoming BlockAckReqs.
      *
      *  2. Prevent double-free bugs.
      */
     super->s.cookie = (u8) cookie + 1;
     return 0;
 }
 
 static void carl9170_release_dev_space(struct ar9170 *ar, struct sk_buff *skb)
 {
     struct _carl9170_tx_superframe *super = (void *) skb->data;
     int cookie;
 
     /* make a local copy of the cookie */
     cookie = super->s.cookie;
     /* invalidate cookie */
     super->s.cookie = 0;
 
     /*
      * Do a out-of-bounds check on the cookie:
      *
      *  * cookie "0" is reserved and won't be assigned to any
      *    out-going frame. Internally however, it is used to
      *    mark no longer/un-accounted frames and serves as a
      *    cheap way of preventing frames from being freed
      *    twice by _accident_. NB: There is a tiny race...
      *
      *  * obviously, cookie number is limited by the amount
      *    of available memory blocks, so the number can
      *    never execeed the mem_blocks count.
      */
     if (WARN_ON_ONCE(cookie == 0) ||
         WARN_ON_ONCE(cookie > ar->fw.mem_blocks))
         return;
 
     atomic_add(DIV_ROUND_UP(skb->len, ar->fw.mem_block_size),
            &ar->mem_free_blocks);
 
     spin_lock_bh(&ar->mem_lock);
     bitmap_release_region(ar->mem_bitmap, cookie - 1, 0);
     spin_unlock_bh(&ar->mem_lock);
 }
 
 /* Called from any context */
 static void carl9170_tx_release(struct kref *ref)
 {
     struct ar9170 *ar;
     struct carl9170_tx_info *arinfo;
     struct ieee80211_tx_info *txinfo;
     struct sk_buff *skb;
 
     arinfo = container_of(ref, struct carl9170_tx_info, ref);
     txinfo = container_of((void *) arinfo, struct ieee80211_tx_info,
                   rate_driver_data);
     skb = container_of((void *) txinfo, struct sk_buff, cb);
 
     ar = arinfo->ar;
     if (WARN_ON_ONCE(!ar))
         return;
 
     /*
      * This does not call ieee80211_tx_info_clear_status() because
      * carl9170_tx_fill_rateinfo() has filled the rate information
      * before we get to this point.
      */
     memset_after(&txinfo->status, 0, rates);
 
     if (atomic_read(&ar->tx_total_queued))
         ar->tx_schedule = true;
 
     if (txinfo->flags & IEEE80211_TX_CTL_AMPDU) {
         if (!atomic_read(&ar->tx_ampdu_upload))
             ar->tx_ampdu_schedule = true;
 
         if (txinfo->flags & IEEE80211_TX_STAT_AMPDU) {
             struct _carl9170_tx_superframe *super;
 
             super = (void *)skb->data;
             txinfo->status.ampdu_len = super->s.rix;
             txinfo->status.ampdu_ack_len = super->s.cnt;
         } else if ((txinfo->flags & IEEE80211_TX_STAT_ACK) &&
                !(txinfo->flags & IEEE80211_TX_CTL_REQ_TX_STATUS)) {
             /*
              * drop redundant tx_status reports:
              *
              * 1. ampdu_ack_len of the final tx_status does
              *    include the feedback of this particular frame.
              *
              * 2. tx_status_irqsafe only queues up to 128
              *    tx feedback reports and discards the rest.
              *
              * 3. minstrel_ht is picky, it only accepts
              *    reports of frames with the TX_STATUS_AMPDU flag.
              *
              * 4. mac80211 is not particularly interested in
              *    feedback either [CTL_REQ_TX_STATUS not set]
              */
 
             ieee80211_free_txskb(ar->hw, skb);
             return;
         } else {
             /*
              * Either the frame transmission has failed or
              * mac80211 requested tx status.
              */
         }
     }
 
     skb_pull(skb, sizeof(struct _carl9170_tx_superframe));
     ieee80211_tx_status_irqsafe(ar->hw, skb);
 }
 
 void carl9170_tx_get_skb(struct sk_buff *skb)
 {
     struct carl9170_tx_info *arinfo = (void *)
         (IEEE80211_SKB_CB(skb))->rate_driver_data;
     kref_get(&arinfo->ref);
 }
 
 int carl9170_tx_put_skb(struct sk_buff *skb)
 {
     struct carl9170_tx_info *arinfo = (void *)
         (IEEE80211_SKB_CB(skb))->rate_driver_data;
 
     return kref_put(&arinfo->ref, carl9170_tx_release);
 }
 
 /* Caller must hold the tid_info->lock & rcu_read_lock */
 static void carl9170_tx_shift_bm(struct ar9170 *ar,
     struct carl9170_sta_tid *tid_info, u16 seq)
 {
     u16 off;
 
     off = SEQ_DIFF(seq, tid_info->bsn);
 
     if (WARN_ON_ONCE(off >= CARL9170_BAW_BITS))
         return;
 
     /*
      * Sanity check. For each MPDU we set the bit in bitmap and
      * clear it once we received the tx_status.
      * But if the bit is already cleared then we've been bitten
      * by a bug.
      */
     WARN_ON_ONCE(!test_and_clear_bit(off, tid_info->bitmap));
 
     off = SEQ_DIFF(tid_info->snx, tid_info->bsn);
     if (WARN_ON_ONCE(off >= CARL9170_BAW_BITS))
         return;
 
     if (!bitmap_empty(tid_info->bitmap, off))
         off = find_first_bit(tid_info->bitmap, off);
 
     tid_info->bsn += off;
     tid_info->bsn &= 0x0fff;
 
     bitmap_shift_right(tid_info->bitmap, tid_info->bitmap,
                off, CARL9170_BAW_BITS);
 }
 
 static void carl9170_tx_status_process_ampdu(struct ar9170 *ar,
     struct sk_buff *skb, struct ieee80211_tx_info *txinfo)
 {
     struct _carl9170_tx_superframe *super = (void *) skb->data;
     struct ieee80211_hdr *hdr = (void *) super->frame_data;
     struct ieee80211_sta *sta;
     struct carl9170_sta_info *sta_info;
     struct carl9170_sta_tid *tid_info;
     u8 tid;
 
     if (!(txinfo->flags & IEEE80211_TX_CTL_AMPDU) ||
         txinfo->flags & IEEE80211_TX_CTL_INJECTED)
         return;
 
     rcu_read_lock();
     sta = __carl9170_get_tx_sta(ar, skb);
     if (unlikely(!sta))
         goto out_rcu;
 
     tid = ieee80211_get_tid(hdr);
 
     sta_info = (void *) sta->drv_priv;
     tid_info = rcu_dereference(sta_info->agg[tid]);
     if (!tid_info)
         goto out_rcu;
 
     spin_lock_bh(&tid_info->lock);
     if (likely(tid_info->state >= CARL9170_TID_STATE_IDLE))
         carl9170_tx_shift_bm(ar, tid_info, get_seq_h(hdr));
 
     if (sta_info->stats[tid].clear) {
         sta_info->stats[tid].clear = false;
         sta_info->stats[tid].req = false;
         sta_info->stats[tid].ampdu_len = 0;
         sta_info->stats[tid].ampdu_ack_len = 0;
     }
 
     sta_info->stats[tid].ampdu_len++;
     if (txinfo->status.rates[0].count == 1)
         sta_info->stats[tid].ampdu_ack_len++;
 
     if (!(txinfo->flags & IEEE80211_TX_STAT_ACK))
         sta_info->stats[tid].req = true;
 
     if (super->f.mac_control & cpu_to_le16(AR9170_TX_MAC_IMM_BA)) {
         super->s.rix = sta_info->stats[tid].ampdu_len;
         super->s.cnt = sta_info->stats[tid].ampdu_ack_len;
         txinfo->flags |= IEEE80211_TX_STAT_AMPDU;
         if (sta_info->stats[tid].req)
             txinfo->flags |= IEEE80211_TX_STAT_AMPDU_NO_BACK;
 
         sta_info->stats[tid].clear = true;
     }
     spin_unlock_bh(&tid_info->lock);
 
 out_rcu:
     rcu_read_unlock();
 }
 
 static void carl9170_tx_bar_status(struct ar9170 *ar, struct sk_buff *skb,
     struct ieee80211_tx_info *tx_info)
 {
     struct _carl9170_tx_superframe *super = (void *) skb->data;
     struct ieee80211_bar *bar = (void *) super->frame_data;
 
     /*
      * Unlike all other frames, the status report for BARs does
      * not directly come from the hardware as it is incapable of
      * matching a BA to a previously send BAR.
      * Instead the RX-path will scan for incoming BAs and set the
      * IEEE80211_TX_STAT_ACK if it sees one that was likely
      * caused by a BAR from us.
      */
 
     if (unlikely(ieee80211_is_back_req(bar->frame_control)) &&
        !(tx_info->flags & IEEE80211_TX_STAT_ACK)) {
         struct carl9170_bar_list_entry *entry;
         int queue = skb_get_queue_mapping(skb);
 
         rcu_read_lock();
         list_for_each_entry_rcu(entry, &ar->bar_list[queue], list) {
             if (entry->skb == skb) {
                 spin_lock_bh(&ar->bar_list_lock[queue]);
                 list_del_rcu(&entry->list);
                 spin_unlock_bh(&ar->bar_list_lock[queue]);
                 kfree_rcu(entry, head);
                 goto out;
             }
         }
 
         WARN(1, "bar not found in %d - ra:%pM ta:%pM c:%x ssn:%x\n",
                queue, bar->ra, bar->ta, bar->control,
             bar->start_seq_num);
 out:
         rcu_read_unlock();
     }
 }
 
 void carl9170_tx_status(struct ar9170 *ar, struct sk_buff *skb,
             const bool success)
 {
     struct ieee80211_tx_info *txinfo;
 
     carl9170_tx_accounting_free(ar, skb);
 
     txinfo = IEEE80211_SKB_CB(skb);
 
     carl9170_tx_bar_status(ar, skb, txinfo);
 
     if (success)
         txinfo->flags |= IEEE80211_TX_STAT_ACK;
     else
         ar->tx_ack_failures++;
 
     if (txinfo->flags & IEEE80211_TX_CTL_AMPDU)
         carl9170_tx_status_process_ampdu(ar, skb, txinfo);
 
     carl9170_tx_ps_unblock(ar, skb);
     carl9170_tx_put_skb(skb);
 }
 
 /* This function may be called form any context */
 void carl9170_tx_callback(struct ar9170 *ar, struct sk_buff *skb)
 {
     struct ieee80211_tx_info *txinfo = IEEE80211_SKB_CB(skb);
 
     atomic_dec(&ar->tx_total_pending);
 
     if (txinfo->flags & IEEE80211_TX_CTL_AMPDU)
         atomic_dec(&ar->tx_ampdu_upload);
 
     if (carl9170_tx_put_skb(skb))
         tasklet_hi_schedule(&ar->usb_tasklet);
 }
 
 static struct sk_buff *carl9170_get_queued_skb(struct ar9170 *ar, u8 cookie,
                            struct sk_buff_head *queue)
 {
     struct sk_buff *skb;
 
     spin_lock_bh(&queue->lock);
     skb_queue_walk(queue, skb) {
         struct _carl9170_tx_superframe *txc = (void *) skb->data;
 
         if (txc->s.cookie != cookie)
             continue;
 
         __skb_unlink(skb, queue);
         spin_unlock_bh(&queue->lock);
 
         carl9170_release_dev_space(ar, skb);
         return skb;
     }
     spin_unlock_bh(&queue->lock);
 
     return NULL;
 }
 
 static void carl9170_tx_fill_rateinfo(struct ar9170 *ar, unsigned int rix,
     unsigned int tries, struct ieee80211_tx_info *txinfo)
 {
     unsigned int i;
 
     for (i = 0; i < IEEE80211_TX_MAX_RATES; i++) {
         if (txinfo->status.rates[i].idx < 0)
             break;
 
         if (i == rix) {
             txinfo->status.rates[i].count = tries;
             i++;
             break;
         }
     }
 
     for (; i < IEEE80211_TX_MAX_RATES; i++) {
         txinfo->status.rates[i].idx = -1;
         txinfo->status.rates[i].count = 0;
     }
 }
 
 static void carl9170_check_queue_stop_timeout(struct ar9170 *ar)
 {
     int i;
     struct sk_buff *skb;
     struct ieee80211_tx_info *txinfo;
     struct carl9170_tx_info *arinfo;
     bool restart = false;
 
     for (i = 0; i < ar->hw->queues; i++) {
         spin_lock_bh(&ar->tx_status[i].lock);
 
         skb = skb_peek(&ar->tx_status[i]);
 
         if (!skb)
             goto next;
 
         txinfo = IEEE80211_SKB_CB(skb);
         arinfo = (void *) txinfo->rate_driver_data;
 
         if (time_is_before_jiffies(arinfo->timeout +
             msecs_to_jiffies(CARL9170_QUEUE_STUCK_TIMEOUT)) == true)
             restart = true;
 
 next:
         spin_unlock_bh(&ar->tx_status[i].lock);
     }
 
     if (restart) {
         /*
          * At least one queue has been stuck for long enough.
          * Give the device a kick and hope it gets back to
          * work.
          *
          * possible reasons may include:
          *  - frames got lost/corrupted (bad connection to the device)
          *  - stalled rx processing/usb controller hiccups
          *  - firmware errors/bugs
          *  - every bug you can think of.
          *  - all bugs you can't...
          *  - ...
          */
         carl9170_restart(ar, CARL9170_RR_STUCK_TX);
     }
 }
 
 static void carl9170_tx_ampdu_timeout(struct ar9170 *ar)
 {
     struct carl9170_sta_tid *iter;
     struct sk_buff *skb;
     struct ieee80211_tx_info *txinfo;
     struct carl9170_tx_info *arinfo;
     struct ieee80211_sta *sta;
 
     rcu_read_lock();
     list_for_each_entry_rcu(iter, &ar->tx_ampdu_list, list) {
         if (iter->state < CARL9170_TID_STATE_IDLE)
             continue;
 
         spin_lock_bh(&iter->lock);
         skb = skb_peek(&iter->queue);
         if (!skb)
             goto unlock;
 
         txinfo = IEEE80211_SKB_CB(skb);
         arinfo = (void *)txinfo->rate_driver_data;
         if (time_is_after_jiffies(arinfo->timeout +
             msecs_to_jiffies(CARL9170_QUEUE_TIMEOUT)))
             goto unlock;
 
         sta = iter->sta;
         if (WARN_ON(!sta))
             goto unlock;
 
         ieee80211_stop_tx_ba_session(sta, iter->tid);
 unlock:
         spin_unlock_bh(&iter->lock);
 
     }
     rcu_read_unlock();
 }
 
 void carl9170_tx_janitor(struct work_struct *work)
 {
     struct ar9170 *ar = container_of(work, struct ar9170,
                      tx_janitor.work);
     if (!IS_STARTED(ar))
         return;
 
     ar->tx_janitor_last_run = jiffies;
 
     carl9170_check_queue_stop_timeout(ar);
     carl9170_tx_ampdu_timeout(ar);
 
     if (!atomic_read(&ar->tx_total_queued))
         return;
 
     ieee80211_queue_delayed_work(ar->hw, &ar->tx_janitor,
         msecs_to_jiffies(CARL9170_TX_TIMEOUT));
 }
 
 static void __carl9170_tx_process_status(struct ar9170 *ar,
     const uint8_t cookie, const uint8_t info)
 {
     struct sk_buff *skb;
     struct ieee80211_tx_info *txinfo;
     unsigned int r, t, q;
     bool success = true;
 
     q = ar9170_qmap(info & CARL9170_TX_STATUS_QUEUE);
 
     skb = carl9170_get_queued_skb(ar, cookie, &ar->tx_status[q]);
     if (!skb) {
         /*
          * We have lost the race to another thread.
          */
 
         return ;
     }
 
     txinfo = IEEE80211_SKB_CB(skb);
 
     if (!(info & CARL9170_TX_STATUS_SUCCESS))
         success = false;
 
     r = (info & CARL9170_TX_STATUS_RIX) >> CARL9170_TX_STATUS_RIX_S;
     t = (info & CARL9170_TX_STATUS_TRIES) >> CARL9170_TX_STATUS_TRIES_S;
 
     carl9170_tx_fill_rateinfo(ar, r, t, txinfo);
     carl9170_tx_status(ar, skb, success);
 }
 
 void carl9170_tx_process_status(struct ar9170 *ar,
                 const struct carl9170_rsp *cmd)
 {
     unsigned int i;
 
     for (i = 0;  i < cmd->hdr.ext; i++) {
         if (WARN_ON(i > ((cmd->hdr.len / 2) + 1))) {
             print_hex_dump_bytes("UU:", DUMP_PREFIX_NONE,
                          (void *) cmd, cmd->hdr.len + 4);
             break;
         }
 
         __carl9170_tx_process_status(ar, cmd->_tx_status[i].cookie,
                          cmd->_tx_status[i].info);
     }
 }
 
 static void carl9170_tx_rate_tpc_chains(struct ar9170 *ar,
     struct ieee80211_tx_info *info, struct ieee80211_tx_rate *txrate,
     unsigned int *phyrate, unsigned int *tpc, unsigned int *chains)
 {
     struct ieee80211_rate *rate = NULL;
     u8 *txpower;
     unsigned int idx;
 
     idx = txrate->idx;
     *tpc = 0;
     *phyrate = 0;
 
     if (txrate->flags & IEEE80211_TX_RC_MCS) {
         if (txrate->flags & IEEE80211_TX_RC_40_MHZ_WIDTH) {
             /* +1 dBm for HT40 */
             *tpc += 2;
 
             if (info->band == NL80211_BAND_2GHZ)
                 txpower = ar->power_2G_ht40;
             else
                 txpower = ar->power_5G_ht40;
         } else {
             if (info->band == NL80211_BAND_2GHZ)
                 txpower = ar->power_2G_ht20;
             else
                 txpower = ar->power_5G_ht20;
         }
 
         *phyrate = txrate->idx;
         *tpc += txpower[idx & 7];
     } else {
         if (info->band == NL80211_BAND_2GHZ) {
             if (idx < 4)
                 txpower = ar->power_2G_cck;
             else
                 txpower = ar->power_2G_ofdm;
         } else {
             txpower = ar->power_5G_leg;
             idx += 4;
         }
 
         rate = &__carl9170_ratetable[idx];
         *tpc += txpower[(rate->hw_value & 0x30) >> 4];
         *phyrate = rate->hw_value & 0xf;
     }
 
     if (ar->eeprom.tx_mask == 1) {
         *chains = AR9170_TX_PHY_TXCHAIN_1;
     } else {
         if (!(txrate->flags & IEEE80211_TX_RC_MCS) &&
             rate && rate->bitrate >= 360)
             *chains = AR9170_TX_PHY_TXCHAIN_1;
         else
             *chains = AR9170_TX_PHY_TXCHAIN_2;
     }
 
     *tpc = min_t(unsigned int, *tpc, ar->hw->conf.power_level * 2);
 }
 
 static __le32 carl9170_tx_physet(struct ar9170 *ar,
     struct ieee80211_tx_info *info, struct ieee80211_tx_rate *txrate)
 {
     unsigned int power = 0, chains = 0, phyrate = 0;
     __le32 tmp;
 
     tmp = cpu_to_le32(0);
 
     if (txrate->flags & IEEE80211_TX_RC_40_MHZ_WIDTH)
         tmp |= cpu_to_le32(AR9170_TX_PHY_BW_40MHZ <<
             AR9170_TX_PHY_BW_S);
     /* this works because 40 MHz is 2 and dup is 3 */
     if (txrate->flags & IEEE80211_TX_RC_DUP_DATA)
         tmp |= cpu_to_le32(AR9170_TX_PHY_BW_40MHZ_DUP <<
             AR9170_TX_PHY_BW_S);
 
     if (txrate->flags & IEEE80211_TX_RC_SHORT_GI)
         tmp |= cpu_to_le32(AR9170_TX_PHY_SHORT_GI);
 
     if (txrate->flags & IEEE80211_TX_RC_MCS) {
         SET_VAL(AR9170_TX_PHY_MCS, phyrate, txrate->idx);
 
         /* heavy clip control */
         tmp |= cpu_to_le32((txrate->idx & 0x7) <<
             AR9170_TX_PHY_TX_HEAVY_CLIP_S);
 
         tmp |= cpu_to_le32(AR9170_TX_PHY_MOD_HT);
 
         /*
          * green field preamble does not work.
          *
          * if (txrate->flags & IEEE80211_TX_RC_GREEN_FIELD)
          * tmp |= cpu_to_le32(AR9170_TX_PHY_GREENFIELD);
          */
     } else {
         if (info->band == NL80211_BAND_2GHZ) {
             if (txrate->idx <= AR9170_TX_PHY_RATE_CCK_11M)
                 tmp |= cpu_to_le32(AR9170_TX_PHY_MOD_CCK);
             else
                 tmp |= cpu_to_le32(AR9170_TX_PHY_MOD_OFDM);
         } else {
             tmp |= cpu_to_le32(AR9170_TX_PHY_MOD_OFDM);
         }
 
         /*
          * short preamble seems to be broken too.
          *
          * if (txrate->flags & IEEE80211_TX_RC_USE_SHORT_PREAMBLE)
          *  tmp |= cpu_to_le32(AR9170_TX_PHY_SHORT_PREAMBLE);
          */
     }
     carl9170_tx_rate_tpc_chains(ar, info, txrate,
                     &phyrate, &power, &chains);
 
     tmp |= cpu_to_le32(SET_CONSTVAL(AR9170_TX_PHY_MCS, phyrate));
     tmp |= cpu_to_le32(SET_CONSTVAL(AR9170_TX_PHY_TX_PWR, power));
     tmp |= cpu_to_le32(SET_CONSTVAL(AR9170_TX_PHY_TXCHAIN, chains));
     return tmp;
 }
 
 static bool carl9170_tx_rts_check(struct ar9170 *ar,
                   struct ieee80211_tx_rate *rate,
                   bool ampdu, bool multi)
 {
     switch (ar->erp_mode) {
     case CARL9170_ERP_AUTO:
         if (ampdu)
             break;
         fallthrough;
 
     case CARL9170_ERP_MAC80211:
         if (!(rate->flags & IEEE80211_TX_RC_USE_RTS_CTS))
             break;
         fallthrough;
 
     case CARL9170_ERP_RTS:
         if (likely(!multi))
             return true;
         break;
 
     default:
         break;
     }
 
     return false;
 }
 
 static bool carl9170_tx_cts_check(struct ar9170 *ar,
                   struct ieee80211_tx_rate *rate)
 {
     switch (ar->erp_mode) {
     case CARL9170_ERP_AUTO:
     case CARL9170_ERP_MAC80211:
         if (!(rate->flags & IEEE80211_TX_RC_USE_CTS_PROTECT))
             break;
         fallthrough;
 
     case CARL9170_ERP_CTS:
         return true;
 
     default:
         break;
     }
 
     return false;
 }
 
 static void carl9170_tx_get_rates(struct ar9170 *ar,
                   struct ieee80211_vif *vif,
                   struct ieee80211_sta *sta,
                   struct sk_buff *skb)
 {
     struct ieee80211_tx_info *info;
 
     BUILD_BUG_ON(IEEE80211_TX_MAX_RATES < CARL9170_TX_MAX_RATES);
     BUILD_BUG_ON(IEEE80211_TX_MAX_RATES > IEEE80211_TX_RATE_TABLE_SIZE);
 
     info = IEEE80211_SKB_CB(skb);
 
     ieee80211_get_tx_rates(vif, sta, skb,
                    info->control.rates,
                    IEEE80211_TX_MAX_RATES);
 }
 
 static void carl9170_tx_apply_rateset(struct ar9170 *ar,
                       struct ieee80211_tx_info *sinfo,
                       struct sk_buff *skb)
 {
     struct ieee80211_tx_rate *txrate;
     struct ieee80211_tx_info *info;
     struct _carl9170_tx_superframe *txc = (void *) skb->data;
     int i;
     bool ampdu;
     bool no_ack;
 
     info = IEEE80211_SKB_CB(skb);
     ampdu = !!(info->flags & IEEE80211_TX_CTL_AMPDU);
     no_ack = !!(info->flags & IEEE80211_TX_CTL_NO_ACK);
 
     /* Set the rate control probe flag for all (sub-) frames.
      * This is because the TX_STATS_AMPDU flag is only set on
      * the last frame, so it has to be inherited.
      */
     info->flags |= (sinfo->flags & IEEE80211_TX_CTL_RATE_CTRL_PROBE);
 
     /* NOTE: For the first rate, the ERP & AMPDU flags are directly
      * taken from mac_control. For all fallback rate, the firmware
      * updates the mac_control flags from the rate info field.
      */
     for (i = 0; i < CARL9170_TX_MAX_RATES; i++) {
         __le32 phy_set;
 
         txrate = &sinfo->control.rates[i];
         if (txrate->idx < 0)
             break;
 
         phy_set = carl9170_tx_physet(ar, info, txrate);
         if (i == 0) {
             __le16 mac_tmp = cpu_to_le16(0);
 
             /* first rate - part of the hw's frame header */
             txc->f.phy_control = phy_set;
 
             if (ampdu && txrate->flags & IEEE80211_TX_RC_MCS)
                 mac_tmp |= cpu_to_le16(AR9170_TX_MAC_AGGR);
 
             if (carl9170_tx_rts_check(ar, txrate, ampdu, no_ack))
                 mac_tmp |= cpu_to_le16(AR9170_TX_MAC_PROT_RTS);
             else if (carl9170_tx_cts_check(ar, txrate))
                 mac_tmp |= cpu_to_le16(AR9170_TX_MAC_PROT_CTS);
 
             txc->f.mac_control |= mac_tmp;
         } else {
             /* fallback rates are stored in the firmware's
              * retry rate set array.
              */
             txc->s.rr[i - 1] = phy_set;
         }
 
         SET_VAL(CARL9170_TX_SUPER_RI_TRIES, txc->s.ri[i],
             txrate->count);
 
         if (carl9170_tx_rts_check(ar, txrate, ampdu, no_ack))
             txc->s.ri[i] |= (AR9170_TX_MAC_PROT_RTS <<
                 CARL9170_TX_SUPER_RI_ERP_PROT_S);
         else if (carl9170_tx_cts_check(ar, txrate))
             txc->s.ri[i] |= (AR9170_TX_MAC_PROT_CTS <<
                 CARL9170_TX_SUPER_RI_ERP_PROT_S);
 
         if (ampdu && (txrate->flags & IEEE80211_TX_RC_MCS))
             txc->s.ri[i] |= CARL9170_TX_SUPER_RI_AMPDU;
     }
 }
 
 static int carl9170_tx_prepare(struct ar9170 *ar,
                    struct ieee80211_sta *sta,
                    struct sk_buff *skb)
 {
     struct ieee80211_hdr *hdr;
     struct _carl9170_tx_superframe *txc;
     struct carl9170_vif_info *cvif;
     struct ieee80211_tx_info *info;
     struct carl9170_tx_info *arinfo;
     unsigned int hw_queue;
     __le16 mac_tmp;
     u16 len;
 
     BUILD_BUG_ON(sizeof(*arinfo) > sizeof(info->rate_driver_data));
     BUILD_BUG_ON(sizeof(struct _carl9170_tx_superdesc) !=
              CARL9170_TX_SUPERDESC_LEN);
 
     BUILD_BUG_ON(sizeof(struct _ar9170_tx_hwdesc) !=
              AR9170_TX_HWDESC_LEN);
 
     BUILD_BUG_ON(AR9170_MAX_VIRTUAL_MAC >
         ((CARL9170_TX_SUPER_MISC_VIF_ID >>
          CARL9170_TX_SUPER_MISC_VIF_ID_S) + 1));
 
     hw_queue = ar9170_qmap(carl9170_get_queue(ar, skb));
 
     hdr = (void *)skb->data;
     info = IEEE80211_SKB_CB(skb);
     len = skb->len;
 
     /*
      * Note: If the frame was sent through a monitor interface,
      * the ieee80211_vif pointer can be NULL.
      */
     if (likely(info->control.vif))
         cvif = (void *) info->control.vif->drv_priv;
     else
         cvif = NULL;
 
     txc = skb_push(skb, sizeof(*txc));
     memset(txc, 0, sizeof(*txc));
 
     SET_VAL(CARL9170_TX_SUPER_MISC_QUEUE, txc->s.misc, hw_queue);
 
     if (likely(cvif))
         SET_VAL(CARL9170_TX_SUPER_MISC_VIF_ID, txc->s.misc, cvif->id);
 
     if (unlikely(info->flags & IEEE80211_TX_CTL_SEND_AFTER_DTIM))
         txc->s.misc |= CARL9170_TX_SUPER_MISC_CAB;
 
     if (unlikely(info->flags & IEEE80211_TX_CTL_ASSIGN_SEQ))
         txc->s.misc |= CARL9170_TX_SUPER_MISC_ASSIGN_SEQ;
 
     if (unlikely(ieee80211_is_probe_resp(hdr->frame_control)))
         txc->s.misc |= CARL9170_TX_SUPER_MISC_FILL_IN_TSF;
 
     mac_tmp = cpu_to_le16(AR9170_TX_MAC_HW_DURATION |
                   AR9170_TX_MAC_BACKOFF);
     mac_tmp |= cpu_to_le16((hw_queue << AR9170_TX_MAC_QOS_S) &
                    AR9170_TX_MAC_QOS);
 
     if (unlikely(info->flags & IEEE80211_TX_CTL_NO_ACK))
         mac_tmp |= cpu_to_le16(AR9170_TX_MAC_NO_ACK);
 
     if (info->control.hw_key) {
         len += info->control.hw_key->icv_len;
 
         switch (info->control.hw_key->cipher) {
         case WLAN_CIPHER_SUITE_WEP40:
         case WLAN_CIPHER_SUITE_WEP104:
         case WLAN_CIPHER_SUITE_TKIP:
             mac_tmp |= cpu_to_le16(AR9170_TX_MAC_ENCR_RC4);
             break;
         case WLAN_CIPHER_SUITE_CCMP:
             mac_tmp |= cpu_to_le16(AR9170_TX_MAC_ENCR_AES);
             break;
         default:
             WARN_ON(1);
             goto err_out;
         }
     }
 
     if (info->flags & IEEE80211_TX_CTL_AMPDU) {
         unsigned int density, factor;
 
         if (unlikely(!sta || !cvif))
             goto err_out;
 
         factor = min_t(unsigned int, 1u,
                    sta->deflink.ht_cap.ampdu_factor);
         density = sta->deflink.ht_cap.ampdu_density;
 
         if (density) {
             /*
              * Watch out!
              *
              * Otus uses slightly different density values than
              * those from the 802.11n spec.
              */
 
             density = max_t(unsigned int, density + 1, 7u);
         }
 
         SET_VAL(CARL9170_TX_SUPER_AMPDU_DENSITY,
             txc->s.ampdu_settings, density);
 
         SET_VAL(CARL9170_TX_SUPER_AMPDU_FACTOR,
             txc->s.ampdu_settings, factor);
     }
 
     txc->s.len = cpu_to_le16(skb->len);
     txc->f.length = cpu_to_le16(len + FCS_LEN);
     txc->f.mac_control = mac_tmp;
 
     arinfo = (void *)info->rate_driver_data;
     arinfo->timeout = jiffies;
     arinfo->ar = ar;
     kref_init(&arinfo->ref);
     return 0;
 
 err_out:
     skb_pull(skb, sizeof(*txc));
     return -EINVAL;
 }
 
 static void carl9170_set_immba(struct ar9170 *ar, struct sk_buff *skb)
 {
     struct _carl9170_tx_superframe *super;
 
     super = (void *) skb->data;
     super->f.mac_control |= cpu_to_le16(AR9170_TX_MAC_IMM_BA);
 }
 
 static void carl9170_set_ampdu_params(struct ar9170 *ar, struct sk_buff *skb)
 {
     struct _carl9170_tx_superframe *super;
     int tmp;
 
     super = (void *) skb->data;
 
     tmp = (super->s.ampdu_settings & CARL9170_TX_SUPER_AMPDU_DENSITY) <<
         CARL9170_TX_SUPER_AMPDU_DENSITY_S;
 
     /*
      * If you haven't noticed carl9170_tx_prepare has already filled
      * in all ampdu spacing & factor parameters.
      * Now it's the time to check whenever the settings have to be
      * updated by the firmware, or if everything is still the same.
      *
      * There's no sane way to handle different density values with
      * this hardware, so we may as well just do the compare in the
      * driver.
      */
 
     if (tmp != ar->current_density) {
         ar->current_density = tmp;
         super->s.ampdu_settings |=
             CARL9170_TX_SUPER_AMPDU_COMMIT_DENSITY;
     }
 
     tmp = (super->s.ampdu_settings & CARL9170_TX_SUPER_AMPDU_FACTOR) <<
         CARL9170_TX_SUPER_AMPDU_FACTOR_S;
 
     if (tmp != ar->current_factor) {
         ar->current_factor = tmp;
         super->s.ampdu_settings |=
             CARL9170_TX_SUPER_AMPDU_COMMIT_FACTOR;
     }
 }
 
 static void carl9170_tx_ampdu(struct ar9170 *ar)
 {
     struct sk_buff_head agg;
     struct carl9170_sta_tid *tid_info;
     struct sk_buff *skb, *first;
     struct ieee80211_tx_info *tx_info_first;
     unsigned int i = 0, done_ampdus = 0;
     u16 seq, queue, tmpssn;
 
     atomic_inc(&ar->tx_ampdu_scheduler);
     ar->tx_ampdu_schedule = false;
 
     if (atomic_read(&ar->tx_ampdu_upload))
         return;
 
     if (!ar->tx_ampdu_list_len)
         return;
 
     __skb_queue_head_init(&agg);
 
     rcu_read_lock();
     tid_info = rcu_dereference(ar->tx_ampdu_iter);
     if (WARN_ON_ONCE(!tid_info)) {
         rcu_read_unlock();
         return;
     }
 
 retry:
     list_for_each_entry_continue_rcu(tid_info, &ar->tx_ampdu_list, list) {
         i++;
 
         if (tid_info->state < CARL9170_TID_STATE_PROGRESS)
             continue;
 
         queue = TID_TO_WME_AC(tid_info->tid);
 
         spin_lock_bh(&tid_info->lock);
         if (tid_info->state != CARL9170_TID_STATE_XMIT)
             goto processed;
 
         tid_info->counter++;
         first = skb_peek(&tid_info->queue);
         tmpssn = carl9170_get_seq(first);
         seq = tid_info->snx;
 
         if (unlikely(tmpssn != seq)) {
             tid_info->state = CARL9170_TID_STATE_IDLE;
 
             goto processed;
         }
 
         tx_info_first = NULL;
         while ((skb = skb_peek(&tid_info->queue))) {
             /* strict 0, 1, ..., n - 1, n frame sequence order */
             if (unlikely(carl9170_get_seq(skb) != seq))
                 break;
 
             /* don't upload more than AMPDU FACTOR allows. */
             if (unlikely(SEQ_DIFF(tid_info->snx, tid_info->bsn) >=
                 (tid_info->max - 1)))
                 break;
 
             if (!tx_info_first) {
                 carl9170_tx_get_rates(ar, tid_info->vif,
                               tid_info->sta, first);
                 tx_info_first = IEEE80211_SKB_CB(first);
             }
 
             carl9170_tx_apply_rateset(ar, tx_info_first, skb);
 
             atomic_inc(&ar->tx_ampdu_upload);
             tid_info->snx = seq = SEQ_NEXT(seq);
             __skb_unlink(skb, &tid_info->queue);
 
             __skb_queue_tail(&agg, skb);
 
             if (skb_queue_len(&agg) >= CARL9170_NUM_TX_AGG_MAX)
                 break;
         }
 
         if (skb_queue_empty(&tid_info->queue) ||
             carl9170_get_seq(skb_peek(&tid_info->queue)) !=
             tid_info->snx) {
             /* stop TID, if A-MPDU frames are still missing,
              * or whenever the queue is empty.
              */
 
             tid_info->state = CARL9170_TID_STATE_IDLE;
         }
         done_ampdus++;
 
 processed:
         spin_unlock_bh(&tid_info->lock);
 
         if (skb_queue_empty(&agg))
             continue;
 
         /* apply ampdu spacing & factor settings */
         carl9170_set_ampdu_params(ar, skb_peek(&agg));
 
         /* set aggregation push bit */
         carl9170_set_immba(ar, skb_peek_tail(&agg));
 
         spin_lock_bh(&ar->tx_pending[queue].lock);
         skb_queue_splice_tail_init(&agg, &ar->tx_pending[queue]);
         spin_unlock_bh(&ar->tx_pending[queue].lock);
         ar->tx_schedule = true;
     }
     if ((done_ampdus++ == 0) && (i++ == 0))
         goto retry;
 
     rcu_assign_pointer(ar->tx_ampdu_iter, tid_info);
     rcu_read_unlock();
 }
 
 static struct sk_buff *carl9170_tx_pick_skb(struct ar9170 *ar,
                         struct sk_buff_head *queue)
 {
     struct sk_buff *skb;
     struct ieee80211_tx_info *info;
     struct carl9170_tx_info *arinfo;
 
     BUILD_BUG_ON(sizeof(*arinfo) > sizeof(info->rate_driver_data));
 
     spin_lock_bh(&queue->lock);
     skb = skb_peek(queue);
     if (unlikely(!skb))
         goto err_unlock;
 
     if (carl9170_alloc_dev_space(ar, skb))
         goto err_unlock;
 
     __skb_unlink(skb, queue);
     spin_unlock_bh(&queue->lock);
 
     info = IEEE80211_SKB_CB(skb);
     arinfo = (void *) info->rate_driver_data;
 
     arinfo->timeout = jiffies;
     return skb;
 
 err_unlock:
     spin_unlock_bh(&queue->lock);
     return NULL;
 }
 
 void carl9170_tx_drop(struct ar9170 *ar, struct sk_buff *skb)
 {
     struct _carl9170_tx_superframe *super;
     uint8_t q = 0;
 
     ar->tx_dropped++;
 
     super = (void *)skb->data;
     SET_VAL(CARL9170_TX_SUPER_MISC_QUEUE, q,
         ar9170_qmap(carl9170_get_queue(ar, skb)));
     __carl9170_tx_process_status(ar, super->s.cookie, q);
 }
 
 static bool carl9170_tx_ps_drop(struct ar9170 *ar, struct sk_buff *skb)
 {
     struct ieee80211_sta *sta;
     struct carl9170_sta_info *sta_info;
     struct ieee80211_tx_info *tx_info;
 
     rcu_read_lock();
     sta = __carl9170_get_tx_sta(ar, skb);
     if (!sta)
         goto out_rcu;
 
     sta_info = (void *) sta->drv_priv;
     tx_info = IEEE80211_SKB_CB(skb);
 
     if (unlikely(sta_info->sleeping) &&
         !(tx_info->flags & (IEEE80211_TX_CTL_NO_PS_BUFFER |
                 IEEE80211_TX_CTL_CLEAR_PS_FILT))) {
         rcu_read_unlock();
 
         if (tx_info->flags & IEEE80211_TX_CTL_AMPDU)
             atomic_dec(&ar->tx_ampdu_upload);
 
         tx_info->flags |= IEEE80211_TX_STAT_TX_FILTERED;
         carl9170_release_dev_space(ar, skb);
         carl9170_tx_status(ar, skb, false);
         return true;
     }
 
 out_rcu:
     rcu_read_unlock();
     return false;
 }
 
 static void carl9170_bar_check(struct ar9170 *ar, struct sk_buff *skb)
 {
     struct _carl9170_tx_superframe *super = (void *) skb->data;
     struct ieee80211_bar *bar = (void *) super->frame_data;
 
     if (unlikely(ieee80211_is_back_req(bar->frame_control)) &&
         skb->len >= sizeof(struct ieee80211_bar)) {
         struct carl9170_bar_list_entry *entry;
         unsigned int queue = skb_get_queue_mapping(skb);
 
         entry = kmalloc(sizeof(*entry), GFP_ATOMIC);
         if (!WARN_ON_ONCE(!entry)) {
             entry->skb = skb;
             spin_lock_bh(&ar->bar_list_lock[queue]);
             list_add_tail_rcu(&entry->list, &ar->bar_list[queue]);
             spin_unlock_bh(&ar->bar_list_lock[queue]);
         }
     }
 }
 
 static void carl9170_tx(struct ar9170 *ar)
 {
     struct sk_buff *skb;
     unsigned int i, q;
     bool schedule_garbagecollector = false;
 
     ar->tx_schedule = false;
 
     if (unlikely(!IS_STARTED(ar)))
         return;
 
     carl9170_usb_handle_tx_err(ar);
 
     for (i = 0; i < ar->hw->queues; i++) {
         while (!skb_queue_empty(&ar->tx_pending[i])) {
             skb = carl9170_tx_pick_skb(ar, &ar->tx_pending[i]);
             if (unlikely(!skb))
                 break;
 
             if (unlikely(carl9170_tx_ps_drop(ar, skb)))
                 continue;
 
             carl9170_bar_check(ar, skb);
 
             atomic_inc(&ar->tx_total_pending);
 
             q = __carl9170_get_queue(ar, i);
             /*
              * NB: tx_status[i] vs. tx_status[q],
              * TODO: Move into pick_skb or alloc_dev_space.
              */
             skb_queue_tail(&ar->tx_status[q], skb);
 
             /*
              * increase ref count to "2".
              * Ref counting is the easiest way to solve the
              * race between the urb's completion routine:
              *  carl9170_tx_callback
              * and wlan tx status functions:
              *  carl9170_tx_status/janitor.
              */
             carl9170_tx_get_skb(skb);
 
             carl9170_usb_tx(ar, skb);
             schedule_garbagecollector = true;
         }
     }
 
     if (!schedule_garbagecollector)
         return;
 
     ieee80211_queue_delayed_work(ar->hw, &ar->tx_janitor,
         msecs_to_jiffies(CARL9170_TX_TIMEOUT));
 }
 
 static bool carl9170_tx_ampdu_queue(struct ar9170 *ar,
     struct ieee80211_sta *sta, struct sk_buff *skb,
     struct ieee80211_tx_info *txinfo)
 {
     struct carl9170_sta_info *sta_info;
     struct carl9170_sta_tid *agg;
     struct sk_buff *iter;
     u16 tid, seq, qseq, off;
     bool run = false;
 
     tid = carl9170_get_tid(skb);
     seq = carl9170_get_seq(skb);
     sta_info = (void *) sta->drv_priv;
 
     rcu_read_lock();
     agg = rcu_dereference(sta_info->agg[tid]);
 
     if (!agg)
         goto err_unlock_rcu;
 
     spin_lock_bh(&agg->lock);
     if (unlikely(agg->state < CARL9170_TID_STATE_IDLE))
         goto err_unlock;
 
     /* check if sequence is within the BA window */
     if (unlikely(!BAW_WITHIN(agg->bsn, CARL9170_BAW_BITS, seq)))
         goto err_unlock;
 
     if (WARN_ON_ONCE(!BAW_WITHIN(agg->snx, CARL9170_BAW_BITS, seq)))
         goto err_unlock;
 
     off = SEQ_DIFF(seq, agg->bsn);
     if (WARN_ON_ONCE(test_and_set_bit(off, agg->bitmap)))
         goto err_unlock;
 
     if (likely(BAW_WITHIN(agg->hsn, CARL9170_BAW_BITS, seq))) {
         __skb_queue_tail(&agg->queue, skb);
         agg->hsn = seq;
         goto queued;
     }
 
     skb_queue_reverse_walk(&agg->queue, iter) {
         qseq = carl9170_get_seq(iter);
 
         if (BAW_WITHIN(qseq, CARL9170_BAW_BITS, seq)) {
             __skb_queue_after(&agg->queue, iter, skb);
             goto queued;
         }
     }
 
     __skb_queue_head(&agg->queue, skb);
 queued:
 
     if (unlikely(agg->state != CARL9170_TID_STATE_XMIT)) {
         if (agg->snx == carl9170_get_seq(skb_peek(&agg->queue))) {
             agg->state = CARL9170_TID_STATE_XMIT;
             run = true;
         }
     }
 
     spin_unlock_bh(&agg->lock);
     rcu_read_unlock();
 
     return run;
 
 err_unlock:
     spin_unlock_bh(&agg->lock);
 
 err_unlock_rcu:
     rcu_read_unlock();
     txinfo->flags &= ~IEEE80211_TX_CTL_AMPDU;
     carl9170_tx_status(ar, skb, false);
     ar->tx_dropped++;
     return false;
 }
 
 void carl9170_op_tx(struct ieee80211_hw *hw,
             struct ieee80211_tx_control *control,
             struct sk_buff *skb)
 {
     struct ar9170 *ar = hw->priv;
     struct ieee80211_tx_info *info;
     struct ieee80211_sta *sta = control->sta;
     struct ieee80211_vif *vif;
     bool run;
 
     if (unlikely(!IS_STARTED(ar)))
         goto err_free;
 
     info = IEEE80211_SKB_CB(skb);
     vif = info->control.vif;
 
     if (unlikely(carl9170_tx_prepare(ar, sta, skb)))
         goto err_free;
 
     carl9170_tx_accounting(ar, skb);
     /*
      * from now on, one has to use carl9170_tx_status to free
      * all ressouces which are associated with the frame.
      */
 
     if (sta) {
         struct carl9170_sta_info *stai = (void *) sta->drv_priv;
         atomic_inc(&stai->pending_frames);
     }
 
     if (info->flags & IEEE80211_TX_CTL_AMPDU) {
         /* to static code analyzers and reviewers:
          * mac80211 guarantees that a valid "sta"
          * reference is present, if a frame is to
          * be part of an ampdu. Hence any extra
          * sta == NULL checks are redundant in this
          * special case.
          */
         run = carl9170_tx_ampdu_queue(ar, sta, skb, info);
         if (run)
             carl9170_tx_ampdu(ar);
 
     } else {
         unsigned int queue = skb_get_queue_mapping(skb);
 
         carl9170_tx_get_rates(ar, vif, sta, skb);
         carl9170_tx_apply_rateset(ar, info, skb);
         skb_queue_tail(&ar->tx_pending[queue], skb);
     }
 
     carl9170_tx(ar);
     return;
 
 err_free:
     ar->tx_dropped++;
     ieee80211_free_txskb(ar->hw, skb);
 }
 
 void carl9170_tx_scheduler(struct ar9170 *ar)
 {
 
     if (ar->tx_ampdu_schedule)
         carl9170_tx_ampdu(ar);
 
     if (ar->tx_schedule)
         carl9170_tx(ar);
 }
 
 /* caller has to take rcu_read_lock */
 static struct carl9170_vif_info *carl9170_pick_beaconing_vif(struct ar9170 *ar)
 {
     struct carl9170_vif_info *cvif;
     int i = 1;
 
     /* The AR9170 hardware has no fancy beacon queue or some
      * other scheduling mechanism. So, the driver has to make
      * due by setting the two beacon timers (pretbtt and tbtt)
      * once and then swapping the beacon address in the HW's
      * register file each time the pretbtt fires.
      */
 
     cvif = rcu_dereference(ar->beacon_iter);
     if (ar->vifs > 0 && cvif) {
         do {
             list_for_each_entry_continue_rcu(cvif, &ar->vif_list,
                              list) {
                 if (cvif->active && cvif->enable_beacon)
                     goto out;
             }
         } while (ar->beacon_enabled && i--);
 
         /* no entry found in list */
         return NULL;
     }
 
 out:
     RCU_INIT_POINTER(ar->beacon_iter, cvif);
     return cvif;
 }
 
 static bool carl9170_tx_beacon_physet(struct ar9170 *ar, struct sk_buff *skb,
                       u32 *ht1, u32 *plcp)
 {
     struct ieee80211_tx_info *txinfo;
     struct ieee80211_tx_rate *rate;
     unsigned int power, chains;
     bool ht_rate;
 
     txinfo = IEEE80211_SKB_CB(skb);
     rate = &txinfo->control.rates[0];
     ht_rate = !!(txinfo->control.rates[0].flags & IEEE80211_TX_RC_MCS);
     carl9170_tx_rate_tpc_chains(ar, txinfo, rate, plcp, &power, &chains);
 
     *ht1 = AR9170_MAC_BCN_HT1_TX_ANT0;
     if (chains == AR9170_TX_PHY_TXCHAIN_2)
         *ht1 |= AR9170_MAC_BCN_HT1_TX_ANT1;
     SET_VAL(AR9170_MAC_BCN_HT1_PWR_CTRL, *ht1, 7);
     SET_VAL(AR9170_MAC_BCN_HT1_TPC, *ht1, power);
     SET_VAL(AR9170_MAC_BCN_HT1_CHAIN_MASK, *ht1, chains);
 
     if (ht_rate) {
         *ht1 |= AR9170_MAC_BCN_HT1_HT_EN;
         if (rate->flags & IEEE80211_TX_RC_SHORT_GI)
             *plcp |= AR9170_MAC_BCN_HT2_SGI;
 
         if (rate->flags & IEEE80211_TX_RC_40_MHZ_WIDTH) {
             *ht1 |= AR9170_MAC_BCN_HT1_BWC_40M_SHARED;
             *plcp |= AR9170_MAC_BCN_HT2_BW40;
         } else if (rate->flags & IEEE80211_TX_RC_DUP_DATA) {
             *ht1 |= AR9170_MAC_BCN_HT1_BWC_40M_DUP;
             *plcp |= AR9170_MAC_BCN_HT2_BW40;
         }
 
         SET_VAL(AR9170_MAC_BCN_HT2_LEN, *plcp, skb->len + FCS_LEN);
     } else {
         if (*plcp <= AR9170_TX_PHY_RATE_CCK_11M)
             *plcp |= ((skb->len + FCS_LEN) << (3 + 16)) + 0x0400;
         else
             *plcp |= ((skb->len + FCS_LEN) << 16) + 0x0010;
     }
 
     return ht_rate;
 }
 
 int carl9170_update_beacon(struct ar9170 *ar, const bool submit)
 {
     struct sk_buff *skb = NULL;
     struct carl9170_vif_info *cvif;
     __le32 *data, *old = NULL;
     u32 word, ht1, plcp, off, addr, len;
     int i = 0, err = 0;
     bool ht_rate;
 
     rcu_read_lock();
     cvif = carl9170_pick_beaconing_vif(ar);
     if (!cvif)
         goto out_unlock;
 
     skb = ieee80211_beacon_get_tim(ar->hw, carl9170_get_vif(cvif),
                        NULL, NULL, 0);
 
     if (!skb) {
         err = -ENOMEM;
         goto err_free;
     }
 
     spin_lock_bh(&ar->beacon_lock);
     data = (__le32 *)skb->data;
     if (cvif->beacon)
         old = (__le32 *)cvif->beacon->data;
 
     off = cvif->id * AR9170_MAC_BCN_LENGTH_MAX;
     addr = ar->fw.beacon_addr + off;
     len = roundup(skb->len + FCS_LEN, 4);
 
     if ((off + len) > ar->fw.beacon_max_len) {
         if (net_ratelimit()) {
             wiphy_err(ar->hw->wiphy, "beacon does not "
                   "fit into device memory!\n");
         }
         err = -EINVAL;
         goto err_unlock;
     }
 
     if (len > AR9170_MAC_BCN_LENGTH_MAX) {
         if (net_ratelimit()) {
             wiphy_err(ar->hw->wiphy, "no support for beacons "
                 "bigger than %d (yours:%d).\n",
                  AR9170_MAC_BCN_LENGTH_MAX, len);
         }
 
         err = -EMSGSIZE;
         goto err_unlock;
     }
 
     ht_rate = carl9170_tx_beacon_physet(ar, skb, &ht1, &plcp);
 
     carl9170_async_regwrite_begin(ar);
     carl9170_async_regwrite(AR9170_MAC_REG_BCN_HT1, ht1);
     if (ht_rate)
         carl9170_async_regwrite(AR9170_MAC_REG_BCN_HT2, plcp);
     else
         carl9170_async_regwrite(AR9170_MAC_REG_BCN_PLCP, plcp);
 
     for (i = 0; i < DIV_ROUND_UP(skb->len, 4); i++) {
         /*
          * XXX: This accesses beyond skb data for up
          *  to the last 3 bytes!!
          */
 
         if (old && (data[i] == old[i]))
             continue;
 
         word = le32_to_cpu(data[i]);
         carl9170_async_regwrite(addr + 4 * i, word);
     }
     carl9170_async_regwrite_finish();
 
     dev_kfree_skb_any(cvif->beacon);
     cvif->beacon = NULL;
 
     err = carl9170_async_regwrite_result();
     if (!err)
         cvif->beacon = skb;
     spin_unlock_bh(&ar->beacon_lock);
     if (err)
         goto err_free;
 
     if (submit) {
         err = carl9170_bcn_ctrl(ar, cvif->id,
                     CARL9170_BCN_CTRL_CAB_TRIGGER,
                     addr, skb->len + FCS_LEN);
 
         if (err)
             goto err_free;
     }
 out_unlock:
     rcu_read_unlock();
     return 0;
 
 err_unlock:
     spin_unlock_bh(&ar->beacon_lock);
 
 err_free:
     rcu_read_unlock();
     dev_kfree_skb_any(skb);
     return err;
 }

This page was automatically generated by the 2.1.0 LXR engine. The LXR team