/*
 * Copyright (c) 2008-2011 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/nl80211.h>
#include <linux/delay.h>
#include "ath9k.h"
#include "btcoex.h"

static void ath9k_set_assoc_state(struct ath_softc *sc,
                                  struct ieee80211_vif *vif);

u8 ath9k_parse_mpdudensity(u8 mpdudensity)
{
        /*
         * 802.11n D2.0 defined values for "Minimum MPDU Start Spacing":
         *   0 for no restriction
         *   1 for 1/4 us
         *   2 for 1/2 us
         *   3 for 1 us
         *   4 for 2 us
         *   5 for 4 us
         *   6 for 8 us
         *   7 for 16 us
         */
        switch (mpdudensity) {
        case 0:
                return 0;
        case 1:
        case 2:
        case 3:
                /* Our lower layer calculations limit our precision to
                   1 microsecond */
                return 1;
        case 4:
                return 2;
        case 5:
                return 4;
        case 6:
                return 8;
        case 7:
                return 16;
        default:
                return 0;
        }
}

static bool ath9k_has_pending_frames(struct ath_softc *sc, struct ath_txq *txq)
{
        bool pending = false;

        spin_lock_bh(&txq->axq_lock);

        if (txq->axq_depth || !list_empty(&txq->axq_acq))
                pending = true;

        spin_unlock_bh(&txq->axq_lock);
        return pending;
}

static bool ath9k_setpower(struct ath_softc *sc, enum ath9k_power_mode mode)
{
        unsigned long flags;
        bool ret;

        spin_lock_irqsave(&sc->sc_pm_lock, flags);
        ret = ath9k_hw_setpower(sc->sc_ah, mode);
        spin_unlock_irqrestore(&sc->sc_pm_lock, flags);

        return ret;
}

void ath9k_ps_wakeup(struct ath_softc *sc)
{
        struct ath_common *common = ath9k_hw_common(sc->sc_ah);
        unsigned long flags;
        enum ath9k_power_mode power_mode;

        spin_lock_irqsave(&sc->sc_pm_lock, flags);
        if (++sc->ps_usecount != 1)
                goto unlock;

        power_mode = sc->sc_ah->power_mode;
        ath9k_hw_setpower(sc->sc_ah, ATH9K_PM_AWAKE);

        /*
         * While the hardware is asleep, the cycle counters contain no
         * useful data. Better clear them now so that they don't mess up
         * survey data results.
         */
        if (power_mode != ATH9K_PM_AWAKE) {
                spin_lock(&common->cc_lock);
                ath_hw_cycle_counters_update(common);
                memset(&common->cc_survey, 0, sizeof(common->cc_survey));
                memset(&common->cc_ani, 0, sizeof(common->cc_ani));
                spin_unlock(&common->cc_lock);
        }

 unlock:
        spin_unlock_irqrestore(&sc->sc_pm_lock, flags);
}

void ath9k_ps_restore(struct ath_softc *sc)
{
        struct ath_common *common = ath9k_hw_common(sc->sc_ah);
        enum ath9k_power_mode mode;
        unsigned long flags;
        bool reset;

        spin_lock_irqsave(&sc->sc_pm_lock, flags);
        if (--sc->ps_usecount != 0)
                goto unlock;

        if (sc->ps_idle) {
                ath9k_hw_setrxabort(sc->sc_ah, 1);
                ath9k_hw_stopdmarecv(sc->sc_ah, &reset);
                mode = ATH9K_PM_FULL_SLEEP;
        } else if (sc->ps_enabled &&
                   !(sc->ps_flags & (PS_WAIT_FOR_BEACON |
                                     PS_WAIT_FOR_CAB |
                                     PS_WAIT_FOR_PSPOLL_DATA |
                                     PS_WAIT_FOR_TX_ACK |
                                     PS_WAIT_FOR_ANI))) {
                mode = ATH9K_PM_NETWORK_SLEEP;
                if (ath9k_hw_btcoex_is_enabled(sc->sc_ah))
                        ath9k_btcoex_stop_gen_timer(sc);
        } else {
                goto unlock;
        }

        spin_lock(&common->cc_lock);
        ath_hw_cycle_counters_update(common);
        spin_unlock(&common->cc_lock);

        ath9k_hw_setpower(sc->sc_ah, mode);

 unlock:
        spin_unlock_irqrestore(&sc->sc_pm_lock, flags);
}

static void __ath_cancel_work(struct ath_softc *sc)
{
        cancel_work_sync(&sc->paprd_work);
        cancel_work_sync(&sc->hw_check_work);
        cancel_delayed_work_sync(&sc->tx_complete_work);
        cancel_delayed_work_sync(&sc->hw_pll_work);

#ifdef CONFIG_ATH9K_BTCOEX_SUPPORT
        if (ath9k_hw_mci_is_enabled(sc->sc_ah))
                cancel_work_sync(&sc->mci_work);
#endif
}

static void ath_cancel_work(struct ath_softc *sc)
{
        __ath_cancel_work(sc);
        cancel_work_sync(&sc->hw_reset_work);
}

static void ath_restart_work(struct ath_softc *sc)
{
        ieee80211_queue_delayed_work(sc->hw, &sc->tx_complete_work, 0);

        if (AR_SREV_9340(sc->sc_ah) || AR_SREV_9330(sc->sc_ah))
                ieee80211_queue_delayed_work(sc->hw, &sc->hw_pll_work,
                                     msecs_to_jiffies(ATH_PLL_WORK_INTERVAL));

        ath_start_rx_poll(sc, 3);
        ath_start_ani(sc);
}

static bool ath_prepare_reset(struct ath_softc *sc)
{
        struct ath_hw *ah = sc->sc_ah;
        bool ret = true;

        ieee80211_stop_queues(sc->hw);

        sc->hw_busy_count = 0;
        ath_stop_ani(sc);
        del_timer_sync(&sc->rx_poll_timer);

        ath9k_hw_disable_interrupts(ah);

        if (!ath_drain_all_txq(sc))
                ret = false;

        if (!ath_stoprecv(sc))
                ret = false;

        return ret;
}

static bool ath_complete_reset(struct ath_softc *sc, bool start)
{
        struct ath_hw *ah = sc->sc_ah;
        struct ath_common *common = ath9k_hw_common(ah);
        unsigned long flags;

        if (ath_startrecv(sc) != 0) {
                ath_err(common, "Unable to restart recv logic\n");
                return false;
        }

        ath9k_cmn_update_txpow(ah, sc->curtxpow,
                               sc->config.txpowlimit, &sc->curtxpow);

        clear_bit(SC_OP_HW_RESET, &sc->sc_flags);
        ath9k_hw_set_interrupts(ah);
        ath9k_hw_enable_interrupts(ah);

        if (!(sc->hw->conf.flags & IEEE80211_CONF_OFFCHANNEL) && start) {
                if (!test_bit(SC_OP_BEACONS, &sc->sc_flags))
                        goto work;

                if (ah->opmode == NL80211_IFTYPE_STATION &&
                    test_bit(SC_OP_PRIM_STA_VIF, &sc->sc_flags)) {
                        spin_lock_irqsave(&sc->sc_pm_lock, flags);
                        sc->ps_flags |= PS_BEACON_SYNC | PS_WAIT_FOR_BEACON;
                        spin_unlock_irqrestore(&sc->sc_pm_lock, flags);
                } else {
                        ath9k_set_beacon(sc);
                }
        work:
                ath_restart_work(sc);
        }

        if ((ah->caps.hw_caps & ATH9K_HW_CAP_ANT_DIV_COMB) && sc->ant_rx != 3)
                ath_ant_comb_update(sc);

        ieee80211_wake_queues(sc->hw);

        return true;
}

static int ath_reset_internal(struct ath_softc *sc, struct ath9k_channel *hchan)
{
        struct ath_hw *ah = sc->sc_ah;
        struct ath_common *common = ath9k_hw_common(ah);
        struct ath9k_hw_cal_data *caldata = NULL;
        bool fastcc = true;
        int r;

        __ath_cancel_work(sc);

        tasklet_disable(&sc->intr_tq);
        spin_lock_bh(&sc->sc_pcu_lock);

        if (!(sc->hw->conf.flags & IEEE80211_CONF_OFFCHANNEL)) {
                fastcc = false;
                caldata = &sc->caldata;
        }

        if (!hchan) {
                fastcc = false;
                hchan = ah->curchan;
        }

        if (!ath_prepare_reset(sc))
                fastcc = false;

        ath_dbg(common, CONFIG, "Reset to %u MHz, HT40: %d fastcc: %d\n",
                hchan->channel, IS_CHAN_HT40(hchan), fastcc);

        r = ath9k_hw_reset(ah, hchan, caldata, fastcc);
        if (r) {
                ath_err(common,
                        "Unable to reset channel, reset status %d\n", r);

                ath9k_hw_enable_interrupts(ah);
                ath9k_queue_reset(sc, RESET_TYPE_BB_HANG);

                goto out;
        }

        if (ath9k_hw_mci_is_enabled(sc->sc_ah) &&
            (sc->hw->conf.flags & IEEE80211_CONF_OFFCHANNEL))
                ath9k_mci_set_txpower(sc, true, false);

        if (!ath_complete_reset(sc, true))
                r = -EIO;

out:
        spin_unlock_bh(&sc->sc_pcu_lock);
        tasklet_enable(&sc->intr_tq);

        return r;
}


/*
 * Set/change channels.  If the channel is really being changed, it's done
 * by reseting the chip.  To accomplish this we must first cleanup any pending
 * DMA, then restart stuff.
*/
static int ath_set_channel(struct ath_softc *sc, struct ieee80211_hw *hw,
                    struct ath9k_channel *hchan)
{
        int r;

        if (test_bit(SC_OP_INVALID, &sc->sc_flags))
                return -EIO;

        r = ath_reset_internal(sc, hchan);

        return r;
}

static void ath_node_attach(struct ath_softc *sc, struct ieee80211_sta *sta,
                            struct ieee80211_vif *vif)
{
        struct ath_node *an;
        an = (struct ath_node *)sta->drv_priv;

        an->sc = sc;
        an->sta = sta;
        an->vif = vif;

        ath_tx_node_init(sc, an);

        if (sta->ht_cap.ht_supported) {
                an->maxampdu = 1 << (IEEE80211_HT_MAX_AMPDU_FACTOR +
                                     sta->ht_cap.ampdu_factor);
                an->mpdudensity = ath9k_parse_mpdudensity(sta->ht_cap.ampdu_density);
        }
}

static void ath_node_detach(struct ath_softc *sc, struct ieee80211_sta *sta)
{
        struct ath_node *an = (struct ath_node *)sta->drv_priv;
        ath_tx_node_cleanup(sc, an);
}

void ath9k_tasklet(unsigned long data)
{
        struct ath_softc *sc = (struct ath_softc *)data;
        struct ath_hw *ah = sc->sc_ah;
        struct ath_common *common = ath9k_hw_common(ah);
        enum ath_reset_type type;
        unsigned long flags;
        u32 status = sc->intrstatus;
        u32 rxmask;

        ath9k_ps_wakeup(sc);
        spin_lock(&sc->sc_pcu_lock);

        if ((status & ATH9K_INT_FATAL) ||
            (status & ATH9K_INT_BB_WATCHDOG)) {

                if (status & ATH9K_INT_FATAL)
                        type = RESET_TYPE_FATAL_INT;
                else
                        type = RESET_TYPE_BB_WATCHDOG;

                ath9k_queue_reset(sc, type);
                goto out;
        }

        spin_lock_irqsave(&sc->sc_pm_lock, flags);
        if ((status & ATH9K_INT_TSFOOR) && sc->ps_enabled) {
                /*
                 * TSF sync does not look correct; remain awake to sync with
                 * the next Beacon.
                 */
                ath_dbg(common, PS, "TSFOOR - Sync with next Beacon\n");
                sc->ps_flags |= PS_WAIT_FOR_BEACON | PS_BEACON_SYNC;
        }
        spin_unlock_irqrestore(&sc->sc_pm_lock, flags);

        if (ah->caps.hw_caps & ATH9K_HW_CAP_EDMA)
                rxmask = (ATH9K_INT_RXHP | ATH9K_INT_RXLP | ATH9K_INT_RXEOL |
                          ATH9K_INT_RXORN);
        else
                rxmask = (ATH9K_INT_RX | ATH9K_INT_RXEOL | ATH9K_INT_RXORN);

        if (status & rxmask) {
                /* Check for high priority Rx first */
                if ((ah->caps.hw_caps & ATH9K_HW_CAP_EDMA) &&
                    (status & ATH9K_INT_RXHP))
                        ath_rx_tasklet(sc, 0, true);

                ath_rx_tasklet(sc, 0, false);
        }

        if (status & ATH9K_INT_TX) {
                if (ah->caps.hw_caps & ATH9K_HW_CAP_EDMA)
                        ath_tx_edma_tasklet(sc);
                else
                        ath_tx_tasklet(sc);
        }

        ath9k_btcoex_handle_interrupt(sc, status);

out:
        /* re-enable hardware interrupt */
        ath9k_hw_enable_interrupts(ah);

        spin_unlock(&sc->sc_pcu_lock);
        ath9k_ps_restore(sc);
}

irqreturn_t ath_isr(int irq, void *dev)
{
#define SCHED_INTR (                            \
                ATH9K_INT_FATAL |               \
                ATH9K_INT_BB_WATCHDOG |         \
                ATH9K_INT_RXORN |               \
                ATH9K_INT_RXEOL |               \
                ATH9K_INT_RX |                  \
                ATH9K_INT_RXLP |                \
                ATH9K_INT_RXHP |                \
                ATH9K_INT_TX |                  \
                ATH9K_INT_BMISS |               \
                ATH9K_INT_CST |                 \
                ATH9K_INT_TSFOOR |              \
                ATH9K_INT_GENTIMER |            \
                ATH9K_INT_MCI)

        struct ath_softc *sc = dev;
        struct ath_hw *ah = sc->sc_ah;
        struct ath_common *common = ath9k_hw_common(ah);
        enum ath9k_int status;
        bool sched = false;

        /*
         * The hardware is not ready/present, don't
         * touch anything. Note this can happen early
         * on if the IRQ is shared.
         */
        if (test_bit(SC_OP_INVALID, &sc->sc_flags))
                return IRQ_NONE;

        /* shared irq, not for us */

        if (!ath9k_hw_intrpend(ah))
                return IRQ_NONE;

        if (test_bit(SC_OP_HW_RESET, &sc->sc_flags)) {
                ath9k_hw_kill_interrupts(ah);
                return IRQ_HANDLED;
        }

        /*
         * Figure out the reason(s) for the interrupt.  Note
         * that the hal returns a pseudo-ISR that may include
         * bits we haven't explicitly enabled so we mask the
         * value to insure we only process bits we requested.
         */
        ath9k_hw_getisr(ah, &status);   /* NB: clears ISR too */
        status &= ah->imask;    /* discard unasked-for bits */

        /*
         * If there are no status bits set, then this interrupt was not
         * for me (should have been caught above).
         */
        if (!status)
                return IRQ_NONE;

        /* Cache the status */
        sc->intrstatus = status;

        if (status & SCHED_INTR)
                sched = true;

        /*
         * If a FATAL or RXORN interrupt is received, we have to reset the
         * chip immediately.
         */
        if ((status & ATH9K_INT_FATAL) || ((status & ATH9K_INT_RXORN) &&
            !(ah->caps.hw_caps & ATH9K_HW_CAP_EDMA)))
                goto chip_reset;

        if ((ah->caps.hw_caps & ATH9K_HW_CAP_EDMA) &&
            (status & ATH9K_INT_BB_WATCHDOG)) {

                spin_lock(&common->cc_lock);
                ath_hw_cycle_counters_update(common);
                ar9003_hw_bb_watchdog_dbg_info(ah);
                spin_unlock(&common->cc_lock);

                goto chip_reset;
        }
#ifdef CONFIG_PM_SLEEP
        if (status & ATH9K_INT_BMISS) {
                if (atomic_read(&sc->wow_sleep_proc_intr) == 0) {
                        ath_dbg(common, ANY, "during WoW we got a BMISS\n");
                        atomic_inc(&sc->wow_got_bmiss_intr);
                        atomic_dec(&sc->wow_sleep_proc_intr);
                }
        }
#endif
        if (status & ATH9K_INT_SWBA)
                tasklet_schedule(&sc->bcon_tasklet);

        if (status & ATH9K_INT_TXURN)
                ath9k_hw_updatetxtriglevel(ah, true);

        if (status & ATH9K_INT_RXEOL) {
                ah->imask &= ~(ATH9K_INT_RXEOL | ATH9K_INT_RXORN);
                ath9k_hw_set_interrupts(ah);
        }

        if (!(ah->caps.hw_caps & ATH9K_HW_CAP_AUTOSLEEP))
                if (status & ATH9K_INT_TIM_TIMER) {
                        if (ATH_DBG_WARN_ON_ONCE(sc->ps_idle))
                                goto chip_reset;
                        /* Clear RxAbort bit so that we can
                         * receive frames */
                        ath9k_setpower(sc, ATH9K_PM_AWAKE);
                        spin_lock(&sc->sc_pm_lock);
                        ath9k_hw_setrxabort(sc->sc_ah, 0);
                        sc->ps_flags |= PS_WAIT_FOR_BEACON;
                        spin_unlock(&sc->sc_pm_lock);
                }

chip_reset:

        ath_debug_stat_interrupt(sc, status);

        if (sched) {
                /* turn off every interrupt */
                ath9k_hw_disable_interrupts(ah);
                tasklet_schedule(&sc->intr_tq);
        }

        return IRQ_HANDLED;

#undef SCHED_INTR
}

static int ath_reset(struct ath_softc *sc)
{
        int i, r;

        ath9k_ps_wakeup(sc);

        r = ath_reset_internal(sc, NULL);

        for (i = 0; i < ATH9K_NUM_TX_QUEUES; i++) {
                if (!ATH_TXQ_SETUP(sc, i))
                        continue;

                spin_lock_bh(&sc->tx.txq[i].axq_lock);
                ath_txq_schedule(sc, &sc->tx.txq[i]);
                spin_unlock_bh(&sc->tx.txq[i].axq_lock);
        }

        ath9k_ps_restore(sc);

        return r;
}

void ath9k_queue_reset(struct ath_softc *sc, enum ath_reset_type type)
{
#ifdef CONFIG_ATH9K_DEBUGFS
        RESET_STAT_INC(sc, type);
#endif
        set_bit(SC_OP_HW_RESET, &sc->sc_flags);
        ieee80211_queue_work(sc->hw, &sc->hw_reset_work);
}

void ath_reset_work(struct work_struct *work)
{
        struct ath_softc *sc = container_of(work, struct ath_softc, hw_reset_work);

        ath_reset(sc);
}

/**********************/
/* mac80211 callbacks */
/**********************/

static int ath9k_start(struct ieee80211_hw *hw)
{
        struct ath_softc *sc = hw->priv;
        struct ath_hw *ah = sc->sc_ah;
        struct ath_common *common = ath9k_hw_common(ah);
        struct ieee80211_channel *curchan = hw->conf.chandef.chan;
        struct ath9k_channel *init_channel;
        int r;

        ath_dbg(common, CONFIG,
                "Starting driver with initial channel: %d MHz\n",
                curchan->center_freq);

        ath9k_ps_wakeup(sc);
        mutex_lock(&sc->mutex);

        init_channel = ath9k_cmn_get_curchannel(hw, ah);

        /* Reset SERDES registers */
        ath9k_hw_configpcipowersave(ah, false);

        /*
         * The basic interface to setting the hardware in a good
         * state is ``reset''.  On return the hardware is known to
         * be powered up and with interrupts disabled.  This must
         * be followed by initialization of the appropriate bits
         * and then setup of the interrupt mask.
         */
        spin_lock_bh(&sc->sc_pcu_lock);

        atomic_set(&ah->intr_ref_cnt, -1);

        r = ath9k_hw_reset(ah, init_channel, ah->caldata, false);
        if (r) {
                ath_err(common,
                        "Unable to reset hardware; reset status %d (freq %u MHz)\n",
                        r, curchan->center_freq);
                ah->reset_power_on = false;
        }

        /* Setup our intr mask. */
        ah->imask = ATH9K_INT_TX | ATH9K_INT_RXEOL |
                    ATH9K_INT_RXORN | ATH9K_INT_FATAL |
                    ATH9K_INT_GLOBAL;

        if (ah->caps.hw_caps & ATH9K_HW_CAP_EDMA)
                ah->imask |= ATH9K_INT_RXHP |
                             ATH9K_INT_RXLP |
                             ATH9K_INT_BB_WATCHDOG;
        else
                ah->imask |= ATH9K_INT_RX;

        ah->imask |= ATH9K_INT_GTT;

        if (ah->caps.hw_caps & ATH9K_HW_CAP_HT)
                ah->imask |= ATH9K_INT_CST;

        ath_mci_enable(sc);

        clear_bit(SC_OP_INVALID, &sc->sc_flags);
        sc->sc_ah->is_monitoring = false;

        if (!ath_complete_reset(sc, false))
                ah->reset_power_on = false;

        if (ah->led_pin >= 0) {
                ath9k_hw_cfg_output(ah, ah->led_pin,
                                    AR_GPIO_OUTPUT_MUX_AS_OUTPUT);
                ath9k_hw_set_gpio(ah, ah->led_pin, 0);
        }

        /*
         * Reset key cache to sane defaults (all entries cleared) instead of
         * semi-random values after suspend/resume.
         */
        ath9k_cmn_init_crypto(sc->sc_ah);

        spin_unlock_bh(&sc->sc_pcu_lock);

        mutex_unlock(&sc->mutex);

        ath9k_ps_restore(sc);

        return 0;
}

static void ath9k_tx(struct ieee80211_hw *hw,
                     struct ieee80211_tx_control *control,
                     struct sk_buff *skb)
{
        struct ath_softc *sc = hw->priv;
        struct ath_common *common = ath9k_hw_common(sc->sc_ah);
        struct ath_tx_control txctl;
        struct ieee80211_hdr *hdr = (struct ieee80211_hdr *) skb->data;
        unsigned long flags;

        if (sc->ps_enabled) {
                /*
                 * mac80211 does not set PM field for normal data frames, so we
                 * need to update that based on the current PS mode.
                 */
                if (ieee80211_is_data(hdr->frame_control) &&
                    !ieee80211_is_nullfunc(hdr->frame_control) &&
                    !ieee80211_has_pm(hdr->frame_control)) {
                        ath_dbg(common, PS,
                                "Add PM=1 for a TX frame while in PS mode\n");
                        hdr->frame_control |= cpu_to_le16(IEEE80211_FCTL_PM);
                }
        }

        if (unlikely(sc->sc_ah->power_mode == ATH9K_PM_NETWORK_SLEEP)) {
                /*
                 * We are using PS-Poll and mac80211 can request TX while in
                 * power save mode. Need to wake up hardware for the TX to be
                 * completed and if needed, also for RX of buffered frames.
                 */
                ath9k_ps_wakeup(sc);
                spin_lock_irqsave(&sc->sc_pm_lock, flags);
                if (!(sc->sc_ah->caps.hw_caps & ATH9K_HW_CAP_AUTOSLEEP))
                        ath9k_hw_setrxabort(sc->sc_ah, 0);
                if (ieee80211_is_pspoll(hdr->frame_control)) {
                        ath_dbg(common, PS,
                                "Sending PS-Poll to pick a buffered frame\n");
                        sc->ps_flags |= PS_WAIT_FOR_PSPOLL_DATA;
                } else {
                        ath_dbg(common, PS, "Wake up to complete TX\n");
                        sc->ps_flags |= PS_WAIT_FOR_TX_ACK;
                }
                /*
                 * The actual restore operation will happen only after
                 * the ps_flags bit is cleared. We are just dropping
                 * the ps_usecount here.
                 */
                spin_unlock_irqrestore(&sc->sc_pm_lock, flags);
                ath9k_ps_restore(sc);
        }

        /*
         * Cannot tx while the hardware is in full sleep, it first needs a full
         * chip reset to recover from that
         */
        if (unlikely(sc->sc_ah->power_mode == ATH9K_PM_FULL_SLEEP)) {
                ath_err(common, "TX while HW is in FULL_SLEEP mode\n");
                goto exit;
        }

        memset(&txctl, 0, sizeof(struct ath_tx_control));
        txctl.txq = sc->tx.txq_map[skb_get_queue_mapping(skb)];
        txctl.sta = control->sta;

        ath_dbg(common, XMIT, "transmitting packet, skb: %p\n", skb);

        if (ath_tx_start(hw, skb, &txctl) != 0) {
                ath_dbg(common, XMIT, "TX failed\n");
                TX_STAT_INC(txctl.txq->axq_qnum, txfailed);
                goto exit;
        }

        return;
exit:
        ieee80211_free_txskb(hw, skb);
}

static void ath9k_stop(struct ieee80211_hw *hw)
{
        struct ath_softc *sc = hw->priv;
        struct ath_hw *ah = sc->sc_ah;
        struct ath_common *common = ath9k_hw_common(ah);
        bool prev_idle;

        mutex_lock(&sc->mutex);

        ath_cancel_work(sc);
        del_timer_sync(&sc->rx_poll_timer);

        if (test_bit(SC_OP_INVALID, &sc->sc_flags)) {
                ath_dbg(common, ANY, "Device not present\n");
                mutex_unlock(&sc->mutex);
                return;
        }

        /* Ensure HW is awake when we try to shut it down. */
        ath9k_ps_wakeup(sc);

        spin_lock_bh(&sc->sc_pcu_lock);

        /* prevent tasklets to enable interrupts once we disable them */
        ah->imask &= ~ATH9K_INT_GLOBAL;

        /* make sure h/w will not generate any interrupt
         * before setting the invalid flag. */
        ath9k_hw_disable_interrupts(ah);

        spin_unlock_bh(&sc->sc_pcu_lock);

        /* we can now sync irq and kill any running tasklets, since we already
         * disabled interrupts and not holding a spin lock */
        synchronize_irq(sc->irq);
        tasklet_kill(&sc->intr_tq);
        tasklet_kill(&sc->bcon_tasklet);

        prev_idle = sc->ps_idle;
        sc->ps_idle = true;

        spin_lock_bh(&sc->sc_pcu_lock);

        if (ah->led_pin >= 0) {
                ath9k_hw_set_gpio(ah, ah->led_pin, 1);
                ath9k_hw_cfg_gpio_input(ah, ah->led_pin);
        }

        ath_prepare_reset(sc);

        if (sc->rx.frag) {
                dev_kfree_skb_any(sc->rx.frag);
                sc->rx.frag = NULL;
        }

        if (!ah->curchan)
                ah->curchan = ath9k_cmn_get_curchannel(hw, ah);

        ath9k_hw_reset(ah, ah->curchan, ah->caldata, false);
        ath9k_hw_phy_disable(ah);

        ath9k_hw_configpcipowersave(ah, true);

        spin_unlock_bh(&sc->sc_pcu_lock);

        ath9k_ps_restore(sc);

        set_bit(SC_OP_INVALID, &sc->sc_flags);
        sc->ps_idle = prev_idle;

        mutex_unlock(&sc->mutex);

        ath_dbg(common, CONFIG, "Driver halt\n");
}

bool ath9k_uses_beacons(int type)
{
        switch (type) {
        case NL80211_IFTYPE_AP:
        case NL80211_IFTYPE_ADHOC:
        case NL80211_IFTYPE_MESH_POINT:
                return true;
        default:
                return false;
        }
}

static void ath9k_vif_iter(void *data, u8 *mac, struct ieee80211_vif *vif)
{
        struct ath9k_vif_iter_data *iter_data = data;
        int i;

        if (iter_data->has_hw_macaddr) {
                for (i = 0; i < ETH_ALEN; i++)
                        iter_data->mask[i] &=
                                ~(iter_data->hw_macaddr[i] ^ mac[i]);
        } else {
                memcpy(iter_data->hw_macaddr, mac, ETH_ALEN);
                iter_data->has_hw_macaddr = true;
        }

        switch (vif->type) {
        case NL80211_IFTYPE_AP:
                iter_data->naps++;
                break;
        case NL80211_IFTYPE_STATION:
                iter_data->nstations++;
                break;
        case NL80211_IFTYPE_ADHOC:
                iter_data->nadhocs++;
                break;
        case NL80211_IFTYPE_MESH_POINT:
                iter_data->nmeshes++;
                break;
        case NL80211_IFTYPE_WDS:
                iter_data->nwds++;
                break;
        default:
                break;
        }
}

static void ath9k_sta_vif_iter(void *data, u8 *mac, struct ieee80211_vif *vif)
{
        struct ath_softc *sc = data;
        struct ath_vif *avp = (void *)vif->drv_priv;

        if (vif->type != NL80211_IFTYPE_STATION)
                return;

        if (avp->primary_sta_vif)
                ath9k_set_assoc_state(sc, vif);
}

/* Called with sc->mutex held. */
void ath9k_calculate_iter_data(struct ieee80211_hw *hw,
                               struct ieee80211_vif *vif,
                               struct ath9k_vif_iter_data *iter_data)
{
        struct ath_softc *sc = hw->priv;
        struct ath_hw *ah = sc->sc_ah;
        struct ath_common *common = ath9k_hw_common(ah);

        /*
         * Use the hardware MAC address as reference, the hardware uses it
         * together with the BSSID mask when matching addresses.
         */
        memset(iter_data, 0, sizeof(*iter_data));
        memset(&iter_data->mask, 0xff, ETH_ALEN);

        if (vif)
                ath9k_vif_iter(iter_data, vif->addr, vif);

        /* Get list of all active MAC addresses */
        ieee80211_iterate_active_interfaces_atomic(
                sc->hw, IEEE80211_IFACE_ITER_RESUME_ALL,
                ath9k_vif_iter, iter_data);

        memcpy(common->macaddr, iter_data->hw_macaddr, ETH_ALEN);
}

/* Called with sc->mutex held. */
static void ath9k_calculate_summary_state(struct ieee80211_hw *hw,
                                          struct ieee80211_vif *vif)
{
        struct ath_softc *sc = hw->priv;
        struct ath_hw *ah = sc->sc_ah;
        struct ath_common *common = ath9k_hw_common(ah);
        struct ath9k_vif_iter_data iter_data;
        enum nl80211_iftype old_opmode = ah->opmode;

        ath9k_calculate_iter_data(hw, vif, &iter_data);

        memcpy(common->bssidmask, iter_data.mask, ETH_ALEN);
        ath_hw_setbssidmask(common);

        if (iter_data.naps > 0) {
                ath9k_hw_set_tsfadjust(ah, true);
                ah->opmode = NL80211_IFTYPE_AP;
        } else {
                ath9k_hw_set_tsfadjust(ah, false);

                if (iter_data.nmeshes)
                        ah->opmode = NL80211_IFTYPE_MESH_POINT;
                else if (iter_data.nwds)
                        ah->opmode = NL80211_IFTYPE_AP;
                else if (iter_data.nadhocs)
                        ah->opmode = NL80211_IFTYPE_ADHOC;
                else
                        ah->opmode = NL80211_IFTYPE_STATION;
        }

        ath9k_hw_setopmode(ah);

        if ((iter_data.nstations + iter_data.nadhocs + iter_data.nmeshes) > 0)
                ah->imask |= ATH9K_INT_TSFOOR;
        else
                ah->imask &= ~ATH9K_INT_TSFOOR;

        ath9k_hw_set_interrupts(ah);

        /*
         * If we are changing the opmode to STATION,
         * a beacon sync needs to be done.
         */
        if (ah->opmode == NL80211_IFTYPE_STATION &&
            old_opmode == NL80211_IFTYPE_AP &&
            test_bit(SC_OP_PRIM_STA_VIF, &sc->sc_flags)) {
                ieee80211_iterate_active_interfaces_atomic(
                        sc->hw, IEEE80211_IFACE_ITER_RESUME_ALL,
                        ath9k_sta_vif_iter, sc);
        }
}

static int ath9k_add_interface(struct ieee80211_hw *hw,
                               struct ieee80211_vif *vif)
{
        struct ath_softc *sc = hw->priv;
        struct ath_hw *ah = sc->sc_ah;
        struct ath_common *common = ath9k_hw_common(ah);

        mutex_lock(&sc->mutex);

        ath_dbg(common, CONFIG, "Attach a VIF of type: %d\n", vif->type);
        sc->nvifs++;

        ath9k_ps_wakeup(sc);
        ath9k_calculate_summary_state(hw, vif);
        ath9k_ps_restore(sc);

        if (ath9k_uses_beacons(vif->type))
                ath9k_beacon_assign_slot(sc, vif);

        mutex_unlock(&sc->mutex);
        return 0;
}

static int ath9k_change_interface(struct ieee80211_hw *hw,
                                  struct ieee80211_vif *vif,
                                  enum nl80211_iftype new_type,
                                  bool p2p)
{
        struct ath_softc *sc = hw->priv;
        struct ath_common *common = ath9k_hw_common(sc->sc_ah);

        ath_dbg(common, CONFIG, "Change Interface\n");
        mutex_lock(&sc->mutex);

        if (ath9k_uses_beacons(vif->type))
                ath9k_beacon_remove_slot(sc, vif);

        vif->type = new_type;
        vif->p2p = p2p;

        ath9k_ps_wakeup(sc);
        ath9k_calculate_summary_state(hw, vif);
        ath9k_ps_restore(sc);

        if (ath9k_uses_beacons(vif->type))
                ath9k_beacon_assign_slot(sc, vif);

        mutex_unlock(&sc->mutex);
        return 0;
}

static void ath9k_remove_interface(struct ieee80211_hw *hw,
                                   struct ieee80211_vif *vif)
{
        struct ath_softc *sc = hw->priv;
        struct ath_common *common = ath9k_hw_common(sc->sc_ah);

        ath_dbg(common, CONFIG, "Detach Interface\n");

        mutex_lock(&sc->mutex);

        sc->nvifs--;

        if (ath9k_uses_beacons(vif->type))
                ath9k_beacon_remove_slot(sc, vif);

        ath9k_ps_wakeup(sc);
        ath9k_calculate_summary_state(hw, NULL);
        ath9k_ps_restore(sc);

        mutex_unlock(&sc->mutex);
}

static void ath9k_enable_ps(struct ath_softc *sc)
{
        struct ath_hw *ah = sc->sc_ah;
        struct ath_common *common = ath9k_hw_common(ah);

        sc->ps_enabled = true;
        if (!(ah->caps.hw_caps & ATH9K_HW_CAP_AUTOSLEEP)) {
                if ((ah->imask & ATH9K_INT_TIM_TIMER) == 0) {
                        ah->imask |= ATH9K_INT_TIM_TIMER;
                        ath9k_hw_set_interrupts(ah);
                }
                ath9k_hw_setrxabort(ah, 1);
        }
        ath_dbg(common, PS, "PowerSave enabled\n");
}

static void ath9k_disable_ps(struct ath_softc *sc)
{
        struct ath_hw *ah = sc->sc_ah;
        struct ath_common *common = ath9k_hw_common(ah);

        sc->ps_enabled = false;
        ath9k_hw_setpower(ah, ATH9K_PM_AWAKE);
        if (!(ah->caps.hw_caps & ATH9K_HW_CAP_AUTOSLEEP)) {
                ath9k_hw_setrxabort(ah, 0);
                sc->ps_flags &= ~(PS_WAIT_FOR_BEACON |
                                  PS_WAIT_FOR_CAB |
                                  PS_WAIT_FOR_PSPOLL_DATA |
                                  PS_WAIT_FOR_TX_ACK);
                if (ah->imask & ATH9K_INT_TIM_TIMER) {
                        ah->imask &= ~ATH9K_INT_TIM_TIMER;
                        ath9k_hw_set_interrupts(ah);
                }
        }
        ath_dbg(common, PS, "PowerSave disabled\n");
}

void ath9k_spectral_scan_trigger(struct ieee80211_hw *hw)
{
        struct ath_softc *sc = hw->priv;
        struct ath_hw *ah = sc->sc_ah;
        struct ath_common *common = ath9k_hw_common(ah);
        u32 rxfilter;

        if (!ath9k_hw_ops(ah)->spectral_scan_trigger) {
                ath_err(common, "spectrum analyzer not implemented on this hardware\n");
                return;
        }

        ath9k_ps_wakeup(sc);
        rxfilter = ath9k_hw_getrxfilter(ah);
        ath9k_hw_setrxfilter(ah, rxfilter |
                                 ATH9K_RX_FILTER_PHYRADAR |
                                 ATH9K_RX_FILTER_PHYERR);

        /* TODO: usually this should not be neccesary, but for some reason
         * (or in some mode?) the trigger must be called after the
         * configuration, otherwise the register will have its values reset
         * (on my ar9220 to value 0x01002310)
         */
        ath9k_spectral_scan_config(hw, sc->spectral_mode);
        ath9k_hw_ops(ah)->spectral_scan_trigger(ah);
        ath9k_ps_restore(sc);
}

int ath9k_spectral_scan_config(struct ieee80211_hw *hw,
                               enum spectral_mode spectral_mode)
{
        struct ath_softc *sc = hw->priv;
        struct ath_hw *ah = sc->sc_ah;
        struct ath_common *common = ath9k_hw_common(ah);

        if (!ath9k_hw_ops(ah)->spectral_scan_trigger) {
                ath_err(common, "spectrum analyzer not implemented on this hardware\n");
                return -1;
        }

        switch (spectral_mode) {
        case SPECTRAL_DISABLED:
                sc->spec_config.enabled = 0;
                break;
        case SPECTRAL_BACKGROUND:
                /* send endless samples.
                 * TODO: is this really useful for "background"?
                 */
                sc->spec_config.endless = 1;
                sc->spec_config.enabled = 1;
                break;
        case SPECTRAL_CHANSCAN:
        case SPECTRAL_MANUAL:
                sc->spec_config.endless = 0;
                sc->spec_config.enabled = 1;
                break;
        default:
                return -1;
        }

        ath9k_ps_wakeup(sc);
        ath9k_hw_ops(ah)->spectral_scan_config(ah, &sc->spec_config);
        ath9k_ps_restore(sc);

        sc->spectral_mode = spectral_mode;

        return 0;
}

static int ath9k_config(struct ieee80211_hw *hw, u32 changed)
{
        struct ath_softc *sc = hw->priv;
        struct ath_hw *ah = sc->sc_ah;
        struct ath_common *common = ath9k_hw_common(ah);
        struct ieee80211_conf *conf = &hw->conf;
        bool reset_channel = false;

        ath9k_ps_wakeup(sc);
        mutex_lock(&sc->mutex);

        if (changed & IEEE80211_CONF_CHANGE_IDLE) {
                sc->ps_idle = !!(conf->flags & IEEE80211_CONF_IDLE);
                if (sc->ps_idle) {
                        ath_cancel_work(sc);
                        ath9k_stop_btcoex(sc);
                } else {
                        ath9k_start_btcoex(sc);
                        /*
                         * The chip needs a reset to properly wake up from
                         * full sleep
                         */
                        reset_channel = ah->chip_fullsleep;
                }
        }

        /*
         * We just prepare to enable PS. We have to wait until our AP has
         * ACK'd our null data frame to disable RX otherwise we'll ignore
         * those ACKs and end up retransmitting the same null data frames.
         * IEEE80211_CONF_CHANGE_PS is only passed by mac80211 for STA mode.
         */
        if (changed & IEEE80211_CONF_CHANGE_PS) {
                unsigned long flags;
                spin_lock_irqsave(&sc->sc_pm_lock, flags);
                if (conf->flags & IEEE80211_CONF_PS)
                        ath9k_enable_ps(sc);
                else
                        ath9k_disable_ps(sc);
                spin_unlock_irqrestore(&sc->sc_pm_lock, flags);
        }

        if (changed & IEEE80211_CONF_CHANGE_MONITOR) {
                if (conf->flags & IEEE80211_CONF_MONITOR) {
                        ath_dbg(common, CONFIG, "Monitor mode is enabled\n");
                        sc->sc_ah->is_monitoring = true;
                } else {
                        ath_dbg(common, CONFIG, "Monitor mode is disabled\n");
                        sc->sc_ah->is_monitoring = false;
                }
        }

        if ((changed & IEEE80211_CONF_CHANGE_CHANNEL) || reset_channel) {
                struct ieee80211_channel *curchan = hw->conf.chandef.chan;
                enum nl80211_channel_type channel_type =
                        cfg80211_get_chandef_type(&conf->chandef);
                int pos = curchan->hw_value;
                int old_pos = -1;
                unsigned long flags;

                if (ah->curchan)
                        old_pos = ah->curchan - &ah->channels[0];

                ath_dbg(common, CONFIG, "Set channel: %d MHz type: %d\n",
                        curchan->center_freq, channel_type);

                /* update survey stats for the old channel before switching */
                spin_lock_irqsave(&common->cc_lock, flags);
                ath_update_survey_stats(sc);
                spin_unlock_irqrestore(&common->cc_lock, flags);

                ath9k_cmn_update_ichannel(&sc->sc_ah->channels[pos],
                                          curchan, channel_type);

                /*
                 * If the operating channel changes, change the survey in-use flags
                 * along with it.
                 * Reset the survey data for the new channel, unless we're switching
                 * back to the operating channel from an off-channel operation.
                 */
                if (!(hw->conf.flags & IEEE80211_CONF_OFFCHANNEL) &&
                    sc->cur_survey != &sc->survey[pos]) {

                        if (sc->cur_survey)
                                sc->cur_survey->filled &= ~SURVEY_INFO_IN_USE;

                        sc->cur_survey = &sc->survey[pos];

                        memset(sc->cur_survey, 0, sizeof(struct survey_info));
                        sc->cur_survey->filled |= SURVEY_INFO_IN_USE;
                } else if (!(sc->survey[pos].filled & SURVEY_INFO_IN_USE)) {
                        memset(&sc->survey[pos], 0, sizeof(struct survey_info));
                }

                if (ath_set_channel(sc, hw, &sc->sc_ah->channels[pos]) < 0) {
                        ath_err(common, "Unable to set channel\n");
                        mutex_unlock(&sc->mutex);
                        ath9k_ps_restore(sc);
                        return -EINVAL;
                }

                /*
                 * The most recent snapshot of channel->noisefloor for the old
                 * channel is only available after the hardware reset. Copy it to
                 * the survey stats now.
                 */
                if (old_pos >= 0)
                        ath_update_survey_nf(sc, old_pos);

                /*
                 * Enable radar pulse detection if on a DFS channel. Spectral
                 * scanning and radar detection can not be used concurrently.
                 */
                if (hw->conf.radar_enabled) {
                        u32 rxfilter;

                        /* set HW specific DFS configuration */
                        ath9k_hw_set_radar_params(ah);
                        rxfilter = ath9k_hw_getrxfilter(ah);
                        rxfilter |= ATH9K_RX_FILTER_PHYRADAR |
                                    ATH9K_RX_FILTER_PHYERR;
                        ath9k_hw_setrxfilter(ah, rxfilter);
                        ath_dbg(common, DFS, "DFS enabled at freq %d\n",
                                curchan->center_freq);
                } else {
                        /* perform spectral scan if requested. */
                        if (test_bit(SC_OP_SCANNING, &sc->sc_flags) &&
                            sc->spectral_mode == SPECTRAL_CHANSCAN)
                                ath9k_spectral_scan_trigger(hw);
                }
        }

        if (changed & IEEE80211_CONF_CHANGE_POWER) {
                ath_dbg(common, CONFIG, "Set power: %d\n", conf->power_level);
                sc->config.txpowlimit = 2 * conf->power_level;
                ath9k_cmn_update_txpow(ah, sc->curtxpow,
                                       sc->config.txpowlimit, &sc->curtxpow);
        }

        mutex_unlock(&sc->mutex);
        ath9k_ps_restore(sc);

        return 0;
}

#define SUPPORTED_FILTERS                       \
        (FIF_PROMISC_IN_BSS |                   \
        FIF_ALLMULTI |                          \
        FIF_CONTROL |                           \
        FIF_PSPOLL |                            \
        FIF_OTHER_BSS |                         \
        FIF_BCN_PRBRESP_PROMISC |               \
        FIF_PROBE_REQ |                         \
        FIF_FCSFAIL)

/* FIXME: sc->sc_full_reset ? */
static void ath9k_configure_filter(struct ieee80211_hw *hw,
                                   unsigned int changed_flags,
                                   unsigned int *total_flags,
                                   u64 multicast)
{
        struct ath_softc *sc = hw->priv;
        u32 rfilt;

        changed_flags &= SUPPORTED_FILTERS;
        *total_flags &= SUPPORTED_FILTERS;

        sc->rx.rxfilter = *total_flags;
        ath9k_ps_wakeup(sc);
        rfilt = ath_calcrxfilter(sc);
        ath9k_hw_setrxfilter(sc->sc_ah, rfilt);
        ath9k_ps_restore(sc);

        ath_dbg(ath9k_hw_common(sc->sc_ah), CONFIG, "Set HW RX filter: 0x%x\n",
                rfilt);
}

static int ath9k_sta_add(struct ieee80211_hw *hw,
                         struct ieee80211_vif *vif,
                         struct ieee80211_sta *sta)
{
        struct ath_softc *sc = hw->priv;
        struct ath_common *common = ath9k_hw_common(sc->sc_ah);
        struct ath_node *an = (struct ath_node *) sta->drv_priv;
        struct ieee80211_key_conf ps_key = { };
        int key;

        ath_node_attach(sc, sta, vif);

        if (vif->type != NL80211_IFTYPE_AP &&
            vif->type != NL80211_IFTYPE_AP_VLAN)
                return 0;

        key = ath_key_config(common, vif, sta, &ps_key);
        if (key > 0)
                an->ps_key = key;

        return 0;
}

static void ath9k_del_ps_key(struct ath_softc *sc,
                             struct ieee80211_vif *vif,
                             struct ieee80211_sta *sta)
{
        struct ath_common *common = ath9k_hw_common(sc->sc_ah);
        struct ath_node *an = (struct ath_node *) sta->drv_priv;
        struct ieee80211_key_conf ps_key = { .hw_key_idx = an->ps_key };

        if (!an->ps_key)
            return;

        ath_key_delete(common, &ps_key);
        an->ps_key = 0;
}

static int ath9k_sta_remove(struct ieee80211_hw *hw,
                            struct ieee80211_vif *vif,
                            struct ieee80211_sta *sta)
{
        struct ath_softc *sc = hw->priv;

        ath9k_del_ps_key(sc, vif, sta);
        ath_node_detach(sc, sta);

        return 0;
}

static void ath9k_sta_notify(struct ieee80211_hw *hw,
                         struct ieee80211_vif *vif,
                         enum sta_notify_cmd cmd,
                         struct ieee80211_sta *sta)
{
        struct ath_softc *sc = hw->priv;
        struct ath_node *an = (struct ath_node *) sta->drv_priv;

        if (!sta->ht_cap.ht_supported)
                return;

        switch (cmd) {
        case STA_NOTIFY_SLEEP:
                an->sleeping = true;
                ath_tx_aggr_sleep(sta, sc, an);
                break;
        case STA_NOTIFY_AWAKE:
                an->sleeping = false;
                ath_tx_aggr_wakeup(sc, an);
                break;
        }
}

static int ath9k_conf_tx(struct ieee80211_hw *hw,
                         struct ieee80211_vif *vif, u16 queue,
                         const struct ieee80211_tx_queue_params *params)
{
        struct ath_softc *sc = hw->priv;
        struct ath_common *common = ath9k_hw_common(sc->sc_ah);
        struct ath_txq *txq;
        struct ath9k_tx_queue_info qi;
        int ret = 0;

        if (queue >= IEEE80211_NUM_ACS)
                return 0;

        txq = sc->tx.txq_map[queue];

        ath9k_ps_wakeup(sc);
        mutex_lock(&sc->mutex);

        memset(&qi, 0, sizeof(struct ath9k_tx_queue_info));

        qi.tqi_aifs = params->aifs;
        qi.tqi_cwmin = params->cw_min;
        qi.tqi_cwmax = params->cw_max;
        qi.tqi_burstTime = params->txop * 32;

        ath_dbg(common, CONFIG,
                "Configure tx [queue/halq] [%d/%d], aifs: %d, cw_min: %d, cw_max: %d, txop: %d\n",
                queue, txq->axq_qnum, params->aifs, params->cw_min,
                params->cw_max, params->txop);

        ath_update_max_aggr_framelen(sc, queue, qi.tqi_burstTime);
        ret = ath_txq_update(sc, txq->axq_qnum, &qi);
        if (ret)
                ath_err(common, "TXQ Update failed\n");

        mutex_unlock(&sc->mutex);
        ath9k_ps_restore(sc);

        return ret;
}

static int ath9k_set_key(struct ieee80211_hw *hw,
                         enum set_key_cmd cmd,
                         struct ieee80211_vif *vif,
                         struct ieee80211_sta *sta,
                         struct ieee80211_key_conf *key)
{
        struct ath_softc *sc = hw->priv;
        struct ath_common *common = ath9k_hw_common(sc->sc_ah);
        int ret = 0;

        if (ath9k_modparam_nohwcrypt)
                return -ENOSPC;

        if ((vif->type == NL80211_IFTYPE_ADHOC ||
             vif->type == NL80211_IFTYPE_MESH_POINT) &&
            (key->cipher == WLAN_CIPHER_SUITE_TKIP ||
             key->cipher == WLAN_CIPHER_SUITE_CCMP) &&
            !(key->flags & IEEE80211_KEY_FLAG_PAIRWISE)) {
                /*
                 * For now, disable hw crypto for the RSN IBSS group keys. This
                 * could be optimized in the future to use a modified key cache
                 * design to support per-STA RX GTK, but until that gets
                 * implemented, use of software crypto for group addressed
                 * frames is a acceptable to allow RSN IBSS to be used.
                 */
                return -EOPNOTSUPP;
        }

        mutex_lock(&sc->mutex);
        ath9k_ps_wakeup(sc);
        ath_dbg(common, CONFIG, "Set HW Key\n");

        switch (cmd) {
        case SET_KEY:
                if (sta)
                        ath9k_del_ps_key(sc, vif, sta);

                ret = ath_key_config(common, vif, sta, key);
                if (ret >= 0) {
                        key->hw_key_idx = ret;
                        /* push IV and Michael MIC generation to stack */
                        key->flags |= IEEE80211_KEY_FLAG_GENERATE_IV;
                        if (key->cipher == WLAN_CIPHER_SUITE_TKIP)
                                key->flags |= IEEE80211_KEY_FLAG_GENERATE_MMIC;
                        if (sc->sc_ah->sw_mgmt_crypto &&
                            key->cipher == WLAN_CIPHER_SUITE_CCMP)
                                key->flags |= IEEE80211_KEY_FLAG_SW_MGMT_TX;
                        ret = 0;
                }
                break;
        case DISABLE_KEY:
                ath_key_delete(common, key);
                break;
        default:
                ret = -EINVAL;
        }

        ath9k_ps_restore(sc);
        mutex_unlock(&sc->mutex);

        return ret;
}

static void ath9k_set_assoc_state(struct ath_softc *sc,
                                  struct ieee80211_vif *vif)
{
        struct ath_common *common = ath9k_hw_common(sc->sc_ah);
        struct ath_vif *avp = (void *)vif->drv_priv;
        struct ieee80211_bss_conf *bss_conf = &vif->bss_conf;
        unsigned long flags;

        set_bit(SC_OP_PRIM_STA_VIF, &sc->sc_flags);
        avp->primary_sta_vif = true;

        /*
         * Set the AID, BSSID and do beacon-sync only when
         * the HW opmode is STATION.
         *
         * But the primary bit is set above in any case.
         */
        if (sc->sc_ah->opmode != NL80211_IFTYPE_STATION)
                return;

        memcpy(common->curbssid, bss_conf->bssid, ETH_ALEN);
        common->curaid = bss_conf->aid;
        ath9k_hw_write_associd(sc->sc_ah);

        sc->last_rssi = ATH_RSSI_DUMMY_MARKER;
        sc->sc_ah->stats.avgbrssi = ATH_RSSI_DUMMY_MARKER;

        spin_lock_irqsave(&sc->sc_pm_lock, flags);
        sc->ps_flags |= PS_BEACON_SYNC | PS_WAIT_FOR_BEACON;
        spin_unlock_irqrestore(&sc->sc_pm_lock, flags);

        if (ath9k_hw_mci_is_enabled(sc->sc_ah))
                ath9k_mci_update_wlan_channels(sc, false);

        ath_dbg(common, CONFIG,
                "Primary Station interface: %pM, BSSID: %pM\n",
                vif->addr, common->curbssid);
}

static void ath9k_bss_assoc_iter(void *data, u8 *mac, struct ieee80211_vif *vif)
{
        struct ath_softc *sc = data;
        struct ieee80211_bss_conf *bss_conf = &vif->bss_conf;

        if (test_bit(SC_OP_PRIM_STA_VIF, &sc->sc_flags))
                return;

        if (bss_conf->assoc)
                ath9k_set_assoc_state(sc, vif);
}

static void ath9k_bss_info_changed(struct ieee80211_hw *hw,
                                   struct ieee80211_vif *vif,
                                   struct ieee80211_bss_conf *bss_conf,
                                   u32 changed)
{
#define CHECK_ANI                               \
        (BSS_CHANGED_ASSOC |                    \
         BSS_CHANGED_IBSS |                     \
         BSS_CHANGED_BEACON_ENABLED)

        struct ath_softc *sc = hw->priv;
        struct ath_hw *ah = sc->sc_ah;
        struct ath_common *common = ath9k_hw_common(ah);
        struct ath_vif *avp = (void *)vif->drv_priv;
        int slottime;

        ath9k_ps_wakeup(sc);
        mutex_lock(&sc->mutex);

        if (changed & BSS_CHANGED_ASSOC) {
                ath_dbg(common, CONFIG, "BSSID %pM Changed ASSOC %d\n",
                        bss_conf->bssid, bss_conf->assoc);

                if (avp->primary_sta_vif && !bss_conf->assoc) {
                        clear_bit(SC_OP_PRIM_STA_VIF, &sc->sc_flags);
                        avp->primary_sta_vif = false;

                        if (ah->opmode == NL80211_IFTYPE_STATION)
                                clear_bit(SC_OP_BEACONS, &sc->sc_flags);
                }

                ieee80211_iterate_active_interfaces_atomic(
                        sc->hw, IEEE80211_IFACE_ITER_RESUME_ALL,
                        ath9k_bss_assoc_iter, sc);

                if (!test_bit(SC_OP_PRIM_STA_VIF, &sc->sc_flags) &&
                    ah->opmode == NL80211_IFTYPE_STATION) {
                        memset(common->curbssid, 0, ETH_ALEN);
                        common->curaid = 0;
                        ath9k_hw_write_associd(sc->sc_ah);
                        if (ath9k_hw_mci_is_enabled(sc->sc_ah))
                                ath9k_mci_update_wlan_channels(sc, true);
                }
        }

        if (changed & BSS_CHANGED_IBSS) {
                memcpy(common->curbssid, bss_conf->bssid, ETH_ALEN);
                common->curaid = bss_conf->aid;
                ath9k_hw_write_associd(sc->sc_ah);
        }

        if ((changed & BSS_CHANGED_BEACON_ENABLED) ||
            (changed & BSS_CHANGED_BEACON_INT)) {
                if (ah->opmode == NL80211_IFTYPE_AP &&
                    bss_conf->enable_beacon)
                        ath9k_set_tsfadjust(sc, vif);
                if (ath9k_allow_beacon_config(sc, vif))
                        ath9k_beacon_config(sc, vif, changed);
        }

        if (changed & BSS_CHANGED_ERP_SLOT) {
                if (bss_conf->use_short_slot)
                        slottime = 9;
                else
                        slottime = 20;
                if (vif->type == NL80211_IFTYPE_AP) {
                        /*
                         * Defer update, so that connected stations can adjust
                         * their settings at the same time.
                         * See beacon.c for more details
                         */
                        sc->beacon.slottime = slottime;
                        sc->beacon.updateslot = UPDATE;
                } else {
                        ah->slottime = slottime;
                        ath9k_hw_init_global_settings(ah);
                }
        }

        if (changed & CHECK_ANI)
                ath_check_ani(sc);

        mutex_unlock(&sc->mutex);
        ath9k_ps_restore(sc);

#undef CHECK_ANI
}

static u64 ath9k_get_tsf(struct ieee80211_hw *hw, struct ieee80211_vif *vif)
{
        struct ath_softc *sc = hw->priv;
        u64 tsf;

        mutex_lock(&sc->mutex);
        ath9k_ps_wakeup(sc);
        tsf = ath9k_hw_gettsf64(sc->sc_ah);
        ath9k_ps_restore(sc);
        mutex_unlock(&sc->mutex);

        return tsf;
}

static void ath9k_set_tsf(struct ieee80211_hw *hw,
                          struct ieee80211_vif *vif,
                          u64 tsf)
{
        struct ath_softc *sc = hw->priv;

        mutex_lock(&sc->mutex);
        ath9k_ps_wakeup(sc);
        ath9k_hw_settsf64(sc->sc_ah, tsf);
        ath9k_ps_restore(sc);
        mutex_unlock(&sc->mutex);
}

static void ath9k_reset_tsf(struct ieee80211_hw *hw, struct ieee80211_vif *vif)
{
        struct ath_softc *sc = hw->priv;

        mutex_lock(&sc->mutex);

        ath9k_ps_wakeup(sc);
        ath9k_hw_reset_tsf(sc->sc_ah);
        ath9k_ps_restore(sc);

        mutex_unlock(&sc->mutex);
}

static int ath9k_ampdu_action(struct ieee80211_hw *hw,
                              struct ieee80211_vif *vif,
                              enum ieee80211_ampdu_mlme_action action,
                              struct ieee80211_sta *sta,
                              u16 tid, u16 *ssn, u8 buf_size)
{
        struct ath_softc *sc = hw->priv;
        bool flush = false;
        int ret = 0;

        mutex_lock(&sc->mutex);

        switch (action) {
        case IEEE80211_AMPDU_RX_START:
                break;
        case IEEE80211_AMPDU_RX_STOP:
                break;
        case IEEE80211_AMPDU_TX_START:
                ath9k_ps_wakeup(sc);
                ret = ath_tx_aggr_start(sc, sta, tid, ssn);
                if (!ret)
                        ieee80211_start_tx_ba_cb_irqsafe(vif, sta->addr, tid);
                ath9k_ps_restore(sc);
                break;
        case IEEE80211_AMPDU_TX_STOP_FLUSH:
        case IEEE80211_AMPDU_TX_STOP_FLUSH_CONT:
                flush = true;
        case IEEE80211_AMPDU_TX_STOP_CONT:
                ath9k_ps_wakeup(sc);
                ath_tx_aggr_stop(sc, sta, tid);
                if (!flush)
                        ieee80211_stop_tx_ba_cb_irqsafe(vif, sta->addr, tid);
                ath9k_ps_restore(sc);
                break;
        case IEEE80211_AMPDU_TX_OPERATIONAL:
                ath9k_ps_wakeup(sc);
                ath_tx_aggr_resume(sc, sta, tid);
                ath9k_ps_restore(sc);
                break;
        default:
                ath_err(ath9k_hw_common(sc->sc_ah), "Unknown AMPDU action\n");
        }

        mutex_unlock(&sc->mutex);

        return ret;
}

static int ath9k_get_survey(struct ieee80211_hw *hw, int idx,
                             struct survey_info *survey)
{
        struct ath_softc *sc = hw->priv;
        struct ath_common *common = ath9k_hw_common(sc->sc_ah);
        struct ieee80211_supported_band *sband;
        struct ieee80211_channel *chan;
        unsigned long flags;
        int pos;

        spin_lock_irqsave(&common->cc_lock, flags);
        if (idx == 0)
                ath_update_survey_stats(sc);

        sband = hw->wiphy->bands[IEEE80211_BAND_2GHZ];
        if (sband && idx >= sband->n_channels) {
                idx -= sband->n_channels;
                sband = NULL;
        }

        if (!sband)
                sband = hw->wiphy->bands[IEEE80211_BAND_5GHZ];

        if (!sband || idx >= sband->n_channels) {
                spin_unlock_irqrestore(&common->cc_lock, flags);
                return -ENOENT;
        }

        chan = &sband->channels[idx];
        pos = chan->hw_value;
        memcpy(survey, &sc->survey[pos], sizeof(*survey));
        survey->channel = chan;
        spin_unlock_irqrestore(&common->cc_lock, flags);

        return 0;
}

static void ath9k_set_coverage_class(struct ieee80211_hw *hw, u8 coverage_class)
{
        struct ath_softc *sc = hw->priv;
        struct ath_hw *ah = sc->sc_ah;

        mutex_lock(&sc->mutex);
        ah->coverage_class = coverage_class;

        ath9k_ps_wakeup(sc);
        ath9k_hw_init_global_settings(ah);
        ath9k_ps_restore(sc);

        mutex_unlock(&sc->mutex);
}

static void ath9k_flush(struct ieee80211_hw *hw, u32 queues, bool drop)
{
        struct ath_softc *sc = hw->priv;
        struct ath_hw *ah = sc->sc_ah;
        struct ath_common *common = ath9k_hw_common(ah);
        int timeout = 200; /* ms */
        int i, j;
        bool drain_txq;

        mutex_lock(&sc->mutex);
        cancel_delayed_work_sync(&sc->tx_complete_work);

        if (ah->ah_flags & AH_UNPLUGGED) {
                ath_dbg(common, ANY, "Device has been unplugged!\n");
                mutex_unlock(&sc->mutex);
                return;
        }

        if (test_bit(SC_OP_INVALID, &sc->sc_flags)) {
                ath_dbg(common, ANY, "Device not present\n");
                mutex_unlock(&sc->mutex);
                return;
        }

        for (j = 0; j < timeout; j++) {
                bool npend = false;

                if (j)
                        usleep_range(1000, 2000);

                for (i = 0; i < ATH9K_NUM_TX_QUEUES; i++) {
                        if (!ATH_TXQ_SETUP(sc, i))
                                continue;

                        npend = ath9k_has_pending_frames(sc, &sc->tx.txq[i]);

                        if (npend)
                                break;
                }

                if (!npend)
                    break;
        }

        if (drop) {
                ath9k_ps_wakeup(sc);
                spin_lock_bh(&sc->sc_pcu_lock);
                drain_txq = ath_drain_all_txq(sc);
                spin_unlock_bh(&sc->sc_pcu_lock);

                if (!drain_txq)
                        ath_reset(sc);

                ath9k_ps_restore(sc);
                ieee80211_wake_queues(hw);
        }

        ieee80211_queue_delayed_work(hw, &sc->tx_complete_work, 0);
        mutex_unlock(&sc->mutex);
}

static bool ath9k_tx_frames_pending(struct ieee80211_hw *hw)
{
        struct ath_softc *sc = hw->priv;
        int i;

        for (i = 0; i < ATH9K_NUM_TX_QUEUES; i++) {
                if (!ATH_TXQ_SETUP(sc, i))
                        continue;

                if (ath9k_has_pending_frames(sc, &sc->tx.txq[i]))
                        return true;
        }
        return false;
}

static int ath9k_tx_last_beacon(struct ieee80211_hw *hw)
{
        struct ath_softc *sc = hw->priv;
        struct ath_hw *ah = sc->sc_ah;
        struct ieee80211_vif *vif;
        struct ath_vif *avp;
        struct ath_buf *bf;
        struct ath_tx_status ts;
        bool edma = !!(ah->caps.hw_caps & ATH9K_HW_CAP_EDMA);
        int status;

        vif = sc->beacon.bslot[0];
        if (!vif)
                return 0;

        if (!vif->bss_conf.enable_beacon)
                return 0;

        avp = (void *)vif->drv_priv;

        if (!sc->beacon.tx_processed && !edma) {
                tasklet_disable(&sc->bcon_tasklet);

                bf = avp->av_bcbuf;
                if (!bf || !bf->bf_mpdu)
                        goto skip;

                status = ath9k_hw_txprocdesc(ah, bf->bf_desc, &ts);
                if (status == -EINPROGRESS)
                        goto skip;

                sc->beacon.tx_processed = true;
                sc->beacon.tx_last = !(ts.ts_status & ATH9K_TXERR_MASK);

skip:
                tasklet_enable(&sc->bcon_tasklet);
        }

        return sc->beacon.tx_last;
}

static int ath9k_get_stats(struct ieee80211_hw *hw,
                           struct ieee80211_low_level_stats *stats)
{
        struct ath_softc *sc = hw->priv;
        struct ath_hw *ah = sc->sc_ah;
        struct ath9k_mib_stats *mib_stats = &ah->ah_mibStats;

        stats->dot11ACKFailureCount = mib_stats->ackrcv_bad;
        stats->dot11RTSFailureCount = mib_stats->rts_bad;
        stats->dot11FCSErrorCount = mib_stats->fcs_bad;
        stats->dot11RTSSuccessCount = mib_stats->rts_good;
        return 0;
}

static u32 fill_chainmask(u32 cap, u32 new)
{
        u32 filled = 0;
        int i;

        for (i = 0; cap && new; i++, cap >>= 1) {
                if (!(cap & BIT(0)))
                        continue;

                if (new & BIT(0))
                        filled |= BIT(i);

                new >>= 1;
        }

        return filled;
}

static bool validate_antenna_mask(struct ath_hw *ah, u32 val)
{
        if (AR_SREV_9300_20_OR_LATER(ah))
                return true;

        switch (val & 0x7) {
        case 0x1:
        case 0x3:
        case 0x7:
                return true;
        case 0x2:
                return (ah->caps.rx_chainmask == 1);
        default:
                return false;
        }
}

static int ath9k_set_antenna(struct ieee80211_hw *hw, u32 tx_ant, u32 rx_ant)
{
        struct ath_softc *sc = hw->priv;
        struct ath_hw *ah = sc->sc_ah;

        if (ah->caps.rx_chainmask != 1)
                rx_ant |= tx_ant;

        if (!validate_antenna_mask(ah, rx_ant) || !tx_ant)
                return -EINVAL;

        sc->ant_rx = rx_ant;
        sc->ant_tx = tx_ant;

        if (ah->caps.rx_chainmask == 1)
                return 0;

        /* AR9100 runs into calibration issues if not all rx chains are enabled */
        if (AR_SREV_9100(ah))
                ah->rxchainmask = 0x7;
        else
                ah->rxchainmask = fill_chainmask(ah->caps.rx_chainmask, rx_ant);

        ah->txchainmask = fill_chainmask(ah->caps.tx_chainmask, tx_ant);
        ath9k_reload_chainmask_settings(sc);

        return 0;
}

static int ath9k_get_antenna(struct ieee80211_hw *hw, u32 *tx_ant, u32 *rx_ant)
{
        struct ath_softc *sc = hw->priv;

        *tx_ant = sc->ant_tx;
        *rx_ant = sc->ant_rx;
        return 0;
}

#ifdef CONFIG_PM_SLEEP

static void ath9k_wow_map_triggers(struct ath_softc *sc,
                                   struct cfg80211_wowlan *wowlan,
                                   u32 *wow_triggers)
{
        if (wowlan->disconnect)
                *wow_triggers |= AH_WOW_LINK_CHANGE |
                                 AH_WOW_BEACON_MISS;
        if (wowlan->magic_pkt)
                *wow_triggers |= AH_WOW_MAGIC_PATTERN_EN;

        if (wowlan->n_patterns)
                *wow_triggers |= AH_WOW_USER_PATTERN_EN;

        sc->wow_enabled = *wow_triggers;

}

static void ath9k_wow_add_disassoc_deauth_pattern(struct ath_softc *sc)
{
        struct ath_hw *ah = sc->sc_ah;
        struct ath_common *common = ath9k_hw_common(ah);

        int pattern_count = 0;
        int i, byte_cnt;
        u8 dis_deauth_pattern[MAX_PATTERN_SIZE];
        u8 dis_deauth_mask[MAX_PATTERN_SIZE];

        memset(dis_deauth_pattern, 0, MAX_PATTERN_SIZE);
        memset(dis_deauth_mask, 0, MAX_PATTERN_SIZE);

        /*
         * Create Dissassociate / Deauthenticate packet filter
         *
         *     2 bytes        2 byte    6 bytes   6 bytes  6 bytes
         *  +--------------+----------+---------+--------+--------+----
         *  + Frame Control+ Duration +   DA    +  SA    +  BSSID +
         *  +--------------+----------+---------+--------+--------+----
         *
         * The above is the management frame format for disassociate/
         * deauthenticate pattern, from this we need to match the first byte
         * of 'Frame Control' and DA, SA, and BSSID fields
         * (skipping 2nd byte of FC and Duration feild.
         *
         * Disassociate pattern
         * --------------------
         * Frame control = 00 00 1010
         * DA, SA, BSSID = x:x:x:x:x:x
         * Pattern will be A0000000 | x:x:x:x:x:x | x:x:x:x:x:x
         *                          | x:x:x:x:x:x  -- 22 bytes
         *
         * Deauthenticate pattern
         * ----------------------
         * Frame control = 00 00 1100
         * DA, SA, BSSID = x:x:x:x:x:x
         * Pattern will be C0000000 | x:x:x:x:x:x | x:x:x:x:x:x
         *                          | x:x:x:x:x:x  -- 22 bytes
         */

        /* Create Disassociate Pattern first */

        byte_cnt = 0;

        /* Fill out the mask with all FF's */

        for (i = 0; i < MAX_PATTERN_MASK_SIZE; i++)
                dis_deauth_mask[i] = 0xff;

        /* copy the first byte of frame control field */
        dis_deauth_pattern[byte_cnt] = 0xa0;
        byte_cnt++;

        /* skip 2nd byte of frame control and Duration field */
        byte_cnt += 3;

        /*
         * need not match the destination mac address, it can be a broadcast
         * mac address or an unicast to this station
         */
        byte_cnt += 6;

        /* copy the source mac address */
        memcpy((dis_deauth_pattern + byte_cnt), common->curbssid, ETH_ALEN);

        byte_cnt += 6;

        /* copy the bssid, its same as the source mac address */

        memcpy((dis_deauth_pattern + byte_cnt), common->curbssid, ETH_ALEN);

        /* Create Disassociate pattern mask */

        dis_deauth_mask[0] = 0xfe;
        dis_deauth_mask[1] = 0x03;
        dis_deauth_mask[2] = 0xc0;

        ath_dbg(common, WOW, "Adding disassoc/deauth patterns for WoW\n");

        ath9k_hw_wow_apply_pattern(ah, dis_deauth_pattern, dis_deauth_mask,
                                   pattern_count, byte_cnt);

        pattern_count++;
        /*
         * for de-authenticate pattern, only the first byte of the frame
         * control field gets changed from 0xA0 to 0xC0
         */
        dis_deauth_pattern[0] = 0xC0;

        ath9k_hw_wow_apply_pattern(ah, dis_deauth_pattern, dis_deauth_mask,
                                   pattern_count, byte_cnt);

}

static void ath9k_wow_add_pattern(struct ath_softc *sc,
                                  struct cfg80211_wowlan *wowlan)
{
        struct ath_hw *ah = sc->sc_ah;
        struct ath9k_wow_pattern *wow_pattern = NULL;
        struct cfg80211_wowlan_trig_pkt_pattern *patterns = wowlan->patterns;
        int mask_len;
        s8 i = 0;

        if (!wowlan->n_patterns)
                return;

        /*
         * Add the new user configured patterns
         */
        for (i = 0; i < wowlan->n_patterns; i++) {

                wow_pattern = kzalloc(sizeof(*wow_pattern), GFP_KERNEL);

                if (!wow_pattern)
                        return;

                /*
                 * TODO: convert the generic user space pattern to
                 * appropriate chip specific/802.11 pattern.
                 */

                mask_len = DIV_ROUND_UP(wowlan->patterns[i].pattern_len, 8);
                memset(wow_pattern->pattern_bytes, 0, MAX_PATTERN_SIZE);
                memset(wow_pattern->mask_bytes, 0, MAX_PATTERN_SIZE);
                memcpy(wow_pattern->pattern_bytes, patterns[i].pattern,
                       patterns[i].pattern_len);
                memcpy(wow_pattern->mask_bytes, patterns[i].mask, mask_len);
                wow_pattern->pattern_len = patterns[i].pattern_len;

                /*
                 * just need to take care of deauth and disssoc pattern,
                 * make sure we don't overwrite them.
                 */

                ath9k_hw_wow_apply_pattern(ah, wow_pattern->pattern_bytes,
                                           wow_pattern->mask_bytes,
                                           i + 2,
                                           wow_pattern->pattern_len);
                kfree(wow_pattern);

        }

}

static int ath9k_suspend(struct ieee80211_hw *hw,
                         struct cfg80211_wowlan *wowlan)
{
        struct ath_softc *sc = hw->priv;
        struct ath_hw *ah = sc->sc_ah;
        struct ath_common *common = ath9k_hw_common(ah);
        u32 wow_triggers_enabled = 0;
        int ret = 0;

        mutex_lock(&sc->mutex);

        ath_cancel_work(sc);
        ath_stop_ani(sc);
        del_timer_sync(&sc->rx_poll_timer);

        if (test_bit(SC_OP_INVALID, &sc->sc_flags)) {
                ath_dbg(common, ANY, "Device not present\n");
                ret = -EINVAL;
                goto fail_wow;
        }

        if (WARN_ON(!wowlan)) {
                ath_dbg(common, WOW, "None of the WoW triggers enabled\n");
                ret = -EINVAL;
                goto fail_wow;
        }

        if (!device_can_wakeup(sc->dev)) {
                ath_dbg(common, WOW, "device_can_wakeup failed, WoW is not enabled\n");
                ret = 1;
                goto fail_wow;
        }

        /*
         * none of the sta vifs are associated
         * and we are not currently handling multivif
         * cases, for instance we have to seperately
         * configure 'keep alive frame' for each
         * STA.
         */

        if (!test_bit(SC_OP_PRIM_STA_VIF, &sc->sc_flags)) {
                ath_dbg(common, WOW, "None of the STA vifs are associated\n");
                ret = 1;
                goto fail_wow;
        }

        if (sc->nvifs > 1) {
                ath_dbg(common, WOW, "WoW for multivif is not yet supported\n");
                ret = 1;
                goto fail_wow;
        }

        ath9k_wow_map_triggers(sc, wowlan, &wow_triggers_enabled);

        ath_dbg(common, WOW, "WoW triggers enabled 0x%x\n",
                wow_triggers_enabled);

        ath9k_ps_wakeup(sc);

        ath9k_stop_btcoex(sc);

        /*
         * Enable wake up on recieving disassoc/deauth
         * frame by default.
         */
        ath9k_wow_add_disassoc_deauth_pattern(sc);

        if (wow_triggers_enabled & AH_WOW_USER_PATTERN_EN)
                ath9k_wow_add_pattern(sc, wowlan);

        spin_lock_bh(&sc->sc_pcu_lock);
        /*
         * To avoid false wake, we enable beacon miss interrupt only
         * when we go to sleep. We save the current interrupt mask
         * so we can restore it after the system wakes up
         */
        sc->wow_intr_before_sleep = ah->imask;
        ah->imask &= ~ATH9K_INT_GLOBAL;
        ath9k_hw_disable_interrupts(ah);
        ah->imask = ATH9K_INT_BMISS | ATH9K_INT_GLOBAL;
        ath9k_hw_set_interrupts(ah);
        ath9k_hw_enable_interrupts(ah);

        spin_unlock_bh(&sc->sc_pcu_lock);

        /*
         * we can now sync irq and kill any running tasklets, since we already
         * disabled interrupts and not holding a spin lock
         */
        synchronize_irq(sc->irq);
        tasklet_kill(&sc->intr_tq);

        ath9k_hw_wow_enable(ah, wow_triggers_enabled);

        ath9k_ps_restore(sc);
        ath_dbg(common, ANY, "WoW enabled in ath9k\n");
        atomic_inc(&sc->wow_sleep_proc_intr);

fail_wow:
        mutex_unlock(&sc->mutex);
        return ret;
}

static int ath9k_resume(struct ieee80211_hw *hw)
{
        struct ath_softc *sc = hw->priv;
        struct ath_hw *ah = sc->sc_ah;
        struct ath_common *common = ath9k_hw_common(ah);
        u32 wow_status;

        mutex_lock(&sc->mutex);

        ath9k_ps_wakeup(sc);

        spin_lock_bh(&sc->sc_pcu_lock);

        ath9k_hw_disable_interrupts(ah);
        ah->imask = sc->wow_intr_before_sleep;
        ath9k_hw_set_interrupts(ah);
        ath9k_hw_enable_interrupts(ah);

        spin_unlock_bh(&sc->sc_pcu_lock);

        wow_status = ath9k_hw_wow_wakeup(ah);

        if (atomic_read(&sc->wow_got_bmiss_intr) == 0) {
                /*
                 * some devices may not pick beacon miss
                 * as the reason they woke up so we add
                 * that here for that shortcoming.
                 */
                wow_status |= AH_WOW_BEACON_MISS;
                atomic_dec(&sc->wow_got_bmiss_intr);
                ath_dbg(common, ANY, "Beacon miss interrupt picked up during WoW sleep\n");
        }

        atomic_dec(&sc->wow_sleep_proc_intr);

        if (wow_status) {
                ath_dbg(common, ANY, "Waking up due to WoW triggers %s with WoW status = %x\n",
                        ath9k_hw_wow_event_to_string(wow_status), wow_status);
        }

        ath_restart_work(sc);
        ath9k_start_btcoex(sc);

        ath9k_ps_restore(sc);
        mutex_unlock(&sc->mutex);

        return 0;
}

static void ath9k_set_wakeup(struct ieee80211_hw *hw, bool enabled)
{
        struct ath_softc *sc = hw->priv;

        mutex_lock(&sc->mutex);
        device_init_wakeup(sc->dev, 1);
        device_set_wakeup_enable(sc->dev, enabled);
        mutex_unlock(&sc->mutex);
}

#endif
static void ath9k_sw_scan_start(struct ieee80211_hw *hw)
{
        struct ath_softc *sc = hw->priv;
        set_bit(SC_OP_SCANNING, &sc->sc_flags);
}

static void ath9k_sw_scan_complete(struct ieee80211_hw *hw)
{
        struct ath_softc *sc = hw->priv;
        clear_bit(SC_OP_SCANNING, &sc->sc_flags);
}

struct ieee80211_ops ath9k_ops = {
        .tx                 = ath9k_tx,
        .start              = ath9k_start,
        .stop               = ath9k_stop,
        .add_interface      = ath9k_add_interface,
        .change_interface   = ath9k_change_interface,
        .remove_interface   = ath9k_remove_interface,
        .config             = ath9k_config,
        .configure_filter   = ath9k_configure_filter,
        .sta_add            = ath9k_sta_add,
        .sta_remove         = ath9k_sta_remove,
        .sta_notify         = ath9k_sta_notify,
        .conf_tx            = ath9k_conf_tx,
        .bss_info_changed   = ath9k_bss_info_changed,
        .set_key            = ath9k_set_key,
        .get_tsf            = ath9k_get_tsf,
        .set_tsf            = ath9k_set_tsf,
        .reset_tsf          = ath9k_reset_tsf,
        .ampdu_action       = ath9k_ampdu_action,
        .get_survey         = ath9k_get_survey,
        .rfkill_poll        = ath9k_rfkill_poll_state,
        .set_coverage_class = ath9k_set_coverage_class,
        .flush              = ath9k_flush,
        .tx_frames_pending  = ath9k_tx_frames_pending,
        .tx_last_beacon     = ath9k_tx_last_beacon,
        .release_buffered_frames = ath9k_release_buffered_frames,
        .get_stats          = ath9k_get_stats,
        .set_antenna        = ath9k_set_antenna,
        .get_antenna        = ath9k_get_antenna,

#ifdef CONFIG_PM_SLEEP
        .suspend            = ath9k_suspend,
        .resume             = ath9k_resume,
        .set_wakeup         = ath9k_set_wakeup,
#endif

#ifdef CONFIG_ATH9K_DEBUGFS
        .get_et_sset_count  = ath9k_get_et_sset_count,
        .get_et_stats       = ath9k_get_et_stats,
        .get_et_strings     = ath9k_get_et_strings,
#endif

#if defined(CONFIG_MAC80211_DEBUGFS) && defined(CONFIG_ATH9K_DEBUGFS)
        .sta_add_debugfs    = ath9k_sta_add_debugfs,
        .sta_remove_debugfs = ath9k_sta_remove_debugfs,
#endif
        .sw_scan_start      = ath9k_sw_scan_start,
        .sw_scan_complete   = ath9k_sw_scan_complete,
};