mac80211: make tx() operation return void

[deliverable/linux.git] / drivers / net / wireless / ath / ath5k / mac80211-ops.c

/*-
 * Copyright (c) 2002-2005 Sam Leffler, Errno Consulting
 * Copyright (c) 2004-2005 Atheros Communications, Inc.
 * Copyright (c) 2006 Devicescape Software, Inc.
 * Copyright (c) 2007 Jiri Slaby <jirislaby@gmail.com>
 * Copyright (c) 2007 Luis R. Rodriguez <mcgrof@winlab.rutgers.edu>
 * Copyright (c) 2010 Bruno Randolf <br1@einfach.org>
 *
 * All rights reserved.
 *
 * Redistribution and use in source and binary forms, with or without
 * modification, are permitted provided that the following conditions
 * are met:
 * 1. Redistributions of source code must retain the above copyright
 *    notice, this list of conditions and the following disclaimer,
 *    without modification.
 * 2. Redistributions in binary form must reproduce at minimum a disclaimer
 *    similar to the "NO WARRANTY" disclaimer below ("Disclaimer") and any
 *    redistribution must be conditioned upon including a substantially
 *    similar Disclaimer requirement for further binary redistribution.
 * 3. Neither the names of the above-listed copyright holders nor the names
 *    of any contributors may be used to endorse or promote products derived
 *    from this software without specific prior written permission.
 *
 * Alternatively, this software may be distributed under the terms of the
 * GNU General Public License ("GPL") version 2 as published by the Free
 * Software Foundation.
 *
 * NO WARRANTY
 * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
 * ``AS IS'' AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
 * LIMITED TO, THE IMPLIED WARRANTIES OF NONINFRINGEMENT, MERCHANTIBILITY
 * AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL
 * THE COPYRIGHT HOLDERS OR CONTRIBUTORS BE LIABLE FOR SPECIAL, EXEMPLARY,
 * OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF
 * SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
 * INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER
 * IN CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
 * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF
 * THE POSSIBILITY OF SUCH DAMAGES.
 *
 */

#include <asm/unaligned.h>

#include "base.h"
#include "reg.h"

extern int ath5k_modparam_nohwcrypt;

/********************\
* Mac80211 functions *
\********************/

static void
ath5k_tx(struct ieee80211_hw *hw, struct sk_buff *skb)
{
        struct ath5k_softc *sc = hw->priv;
        u16 qnum = skb_get_queue_mapping(skb);

        if (WARN_ON(qnum >= sc->ah->ah_capabilities.cap_queues.q_tx_num)) {
                dev_kfree_skb_any(skb);
                return;
        }

        ath5k_tx_queue(hw, skb, &sc->txqs[qnum]);
}


static int
ath5k_start(struct ieee80211_hw *hw)
{
        return ath5k_init_hw(hw->priv);
}


static void
ath5k_stop(struct ieee80211_hw *hw)
{
        ath5k_stop_hw(hw->priv);
}


static int
ath5k_add_interface(struct ieee80211_hw *hw, struct ieee80211_vif *vif)
{
        struct ath5k_softc *sc = hw->priv;
        int ret;
        struct ath5k_vif *avf = (void *)vif->drv_priv;

        mutex_lock(&sc->lock);

        if ((vif->type == NL80211_IFTYPE_AP ||
             vif->type == NL80211_IFTYPE_ADHOC)
            && (sc->num_ap_vifs + sc->num_adhoc_vifs) >= ATH_BCBUF) {
                ret = -ELNRNG;
                goto end;
        }

        /* Don't allow other interfaces if one ad-hoc is configured.
         * TODO: Fix the problems with ad-hoc and multiple other interfaces.
         * We would need to operate the HW in ad-hoc mode to allow TSF updates
         * for the IBSS, but this breaks with additional AP or STA interfaces
         * at the moment. */
        if (sc->num_adhoc_vifs ||
            (sc->nvifs && vif->type == NL80211_IFTYPE_ADHOC)) {
                ATH5K_ERR(sc, "Only one single ad-hoc interface is allowed.\n");
                ret = -ELNRNG;
                goto end;
        }

        switch (vif->type) {
        case NL80211_IFTYPE_AP:
        case NL80211_IFTYPE_STATION:
        case NL80211_IFTYPE_ADHOC:
        case NL80211_IFTYPE_MESH_POINT:
                avf->opmode = vif->type;
                break;
        default:
                ret = -EOPNOTSUPP;
                goto end;
        }

        sc->nvifs++;
        ATH5K_DBG(sc, ATH5K_DEBUG_MODE, "add interface mode %d\n", avf->opmode);

        /* Assign the vap/adhoc to a beacon xmit slot. */
        if ((avf->opmode == NL80211_IFTYPE_AP) ||
            (avf->opmode == NL80211_IFTYPE_ADHOC) ||
            (avf->opmode == NL80211_IFTYPE_MESH_POINT)) {
                int slot;

                WARN_ON(list_empty(&sc->bcbuf));
                avf->bbuf = list_first_entry(&sc->bcbuf, struct ath5k_buf,
                                             list);
                list_del(&avf->bbuf->list);

                avf->bslot = 0;
                for (slot = 0; slot < ATH_BCBUF; slot++) {
                        if (!sc->bslot[slot]) {
                                avf->bslot = slot;
                                break;
                        }
                }
                BUG_ON(sc->bslot[avf->bslot] != NULL);
                sc->bslot[avf->bslot] = vif;
                if (avf->opmode == NL80211_IFTYPE_AP)
                        sc->num_ap_vifs++;
                else if (avf->opmode == NL80211_IFTYPE_ADHOC)
                        sc->num_adhoc_vifs++;
        }

        /* Any MAC address is fine, all others are included through the
         * filter.
         */
        memcpy(&sc->lladdr, vif->addr, ETH_ALEN);
        ath5k_hw_set_lladdr(sc->ah, vif->addr);

        memcpy(&avf->lladdr, vif->addr, ETH_ALEN);

        ath5k_mode_setup(sc, vif);

        ret = 0;
end:
        mutex_unlock(&sc->lock);
        return ret;
}


static void
ath5k_remove_interface(struct ieee80211_hw *hw,
                       struct ieee80211_vif *vif)
{
        struct ath5k_softc *sc = hw->priv;
        struct ath5k_vif *avf = (void *)vif->drv_priv;
        unsigned int i;

        mutex_lock(&sc->lock);
        sc->nvifs--;

        if (avf->bbuf) {
                ath5k_txbuf_free_skb(sc, avf->bbuf);
                list_add_tail(&avf->bbuf->list, &sc->bcbuf);
                for (i = 0; i < ATH_BCBUF; i++) {
                        if (sc->bslot[i] == vif) {
                                sc->bslot[i] = NULL;
                                break;
                        }
                }
                avf->bbuf = NULL;
        }
        if (avf->opmode == NL80211_IFTYPE_AP)
                sc->num_ap_vifs--;
        else if (avf->opmode == NL80211_IFTYPE_ADHOC)
                sc->num_adhoc_vifs--;

        ath5k_update_bssid_mask_and_opmode(sc, NULL);
        mutex_unlock(&sc->lock);
}


/*
 * TODO: Phy disable/diversity etc
 */
static int
ath5k_config(struct ieee80211_hw *hw, u32 changed)
{
        struct ath5k_softc *sc = hw->priv;
        struct ath5k_hw *ah = sc->ah;
        struct ieee80211_conf *conf = &hw->conf;
        int ret = 0;
        int i;

        mutex_lock(&sc->lock);

        if (changed & IEEE80211_CONF_CHANGE_CHANNEL) {
                ret = ath5k_chan_set(sc, conf->channel);
                if (ret < 0)
                        goto unlock;
        }

        if ((changed & IEEE80211_CONF_CHANGE_POWER) &&
        (sc->power_level != conf->power_level)) {
                sc->power_level = conf->power_level;

                /* Half dB steps */
                ath5k_hw_set_txpower_limit(ah, (conf->power_level * 2));
        }

        if (changed & IEEE80211_CONF_CHANGE_RETRY_LIMITS) {
                ah->ah_retry_long = conf->long_frame_max_tx_count;
                ah->ah_retry_short = conf->short_frame_max_tx_count;

                for (i = 0; i < ah->ah_capabilities.cap_queues.q_tx_num; i++)
                        ath5k_hw_set_tx_retry_limits(ah, i);
        }

        /* TODO:
         * 1) Move this on config_interface and handle each case
         * separately eg. when we have only one STA vif, use
         * AR5K_ANTMODE_SINGLE_AP
         *
         * 2) Allow the user to change antenna mode eg. when only
         * one antenna is present
         *
         * 3) Allow the user to set default/tx antenna when possible
         *
         * 4) Default mode should handle 90% of the cases, together
         * with fixed a/b and single AP modes we should be able to
         * handle 99%. Sectored modes are extreme cases and i still
         * haven't found a usage for them. If we decide to support them,
         * then we must allow the user to set how many tx antennas we
         * have available
         */
        ath5k_hw_set_antenna_mode(ah, ah->ah_ant_mode);

unlock:
        mutex_unlock(&sc->lock);
        return ret;
}


static void
ath5k_bss_info_changed(struct ieee80211_hw *hw, struct ieee80211_vif *vif,
                       struct ieee80211_bss_conf *bss_conf, u32 changes)
{
        struct ath5k_vif *avf = (void *)vif->drv_priv;
        struct ath5k_softc *sc = hw->priv;
        struct ath5k_hw *ah = sc->ah;
        struct ath_common *common = ath5k_hw_common(ah);
        unsigned long flags;

        mutex_lock(&sc->lock);

        if (changes & BSS_CHANGED_BSSID) {
                /* Cache for later use during resets */
                memcpy(common->curbssid, bss_conf->bssid, ETH_ALEN);
                common->curaid = 0;
                ath5k_hw_set_bssid(ah);
                mmiowb();
        }

        if (changes & BSS_CHANGED_BEACON_INT)
                sc->bintval = bss_conf->beacon_int;

        if (changes & BSS_CHANGED_ASSOC) {
                avf->assoc = bss_conf->assoc;
                if (bss_conf->assoc)
                        sc->assoc = bss_conf->assoc;
                else
                        sc->assoc = ath_any_vif_assoc(sc);

                if (sc->opmode == NL80211_IFTYPE_STATION)
                        set_beacon_filter(hw, sc->assoc);
                ath5k_hw_set_ledstate(sc->ah, sc->assoc ?
                        AR5K_LED_ASSOC : AR5K_LED_INIT);
                if (bss_conf->assoc) {
                        ATH5K_DBG(sc, ATH5K_DEBUG_ANY,
                                  "Bss Info ASSOC %d, bssid: %pM\n",
                                  bss_conf->aid, common->curbssid);
                        common->curaid = bss_conf->aid;
                        ath5k_hw_set_bssid(ah);
                        /* Once ANI is available you would start it here */
                }
        }

        if (changes & BSS_CHANGED_BEACON) {
                spin_lock_irqsave(&sc->block, flags);
                ath5k_beacon_update(hw, vif);
                spin_unlock_irqrestore(&sc->block, flags);
        }

        if (changes & BSS_CHANGED_BEACON_ENABLED)
                sc->enable_beacon = bss_conf->enable_beacon;

        if (changes & (BSS_CHANGED_BEACON | BSS_CHANGED_BEACON_ENABLED |
                       BSS_CHANGED_BEACON_INT))
                ath5k_beacon_config(sc);

        mutex_unlock(&sc->lock);
}


static u64
ath5k_prepare_multicast(struct ieee80211_hw *hw,
                        struct netdev_hw_addr_list *mc_list)
{
        u32 mfilt[2], val;
        u8 pos;
        struct netdev_hw_addr *ha;

        mfilt[0] = 0;
        mfilt[1] = 1;

        netdev_hw_addr_list_for_each(ha, mc_list) {
                /* calculate XOR of eight 6-bit values */
                val = get_unaligned_le32(ha->addr + 0);
                pos = (val >> 18) ^ (val >> 12) ^ (val >> 6) ^ val;
                val = get_unaligned_le32(ha->addr + 3);
                pos ^= (val >> 18) ^ (val >> 12) ^ (val >> 6) ^ val;
                pos &= 0x3f;
                mfilt[pos / 32] |= (1 << (pos % 32));
                /* XXX: we might be able to just do this instead,
                * but not sure, needs testing, if we do use this we'd
                * neet to inform below to not reset the mcast */
                /* ath5k_hw_set_mcast_filterindex(ah,
                 *      ha->addr[5]); */
        }

        return ((u64)(mfilt[1]) << 32) | mfilt[0];
}


/*
 * o always accept unicast, broadcast, and multicast traffic
 * o multicast traffic for all BSSIDs will be enabled if mac80211
 *   says it should be
 * o maintain current state of phy ofdm or phy cck error reception.
 *   If the hardware detects any of these type of errors then
 *   ath5k_hw_get_rx_filter() will pass to us the respective
 *   hardware filters to be able to receive these type of frames.
 * o probe request frames are accepted only when operating in
 *   hostap, adhoc, or monitor modes
 * o enable promiscuous mode according to the interface state
 * o accept beacons:
 *   - when operating in adhoc mode so the 802.11 layer creates
 *     node table entries for peers,
 *   - when operating in station mode for collecting rssi data when
 *     the station is otherwise quiet, or
 *   - when scanning
 */
static void
ath5k_configure_filter(struct ieee80211_hw *hw, unsigned int changed_flags,
                       unsigned int *new_flags, u64 multicast)
{
#define SUPPORTED_FIF_FLAGS \
        (FIF_PROMISC_IN_BSS |  FIF_ALLMULTI | FIF_FCSFAIL | \
        FIF_PLCPFAIL | FIF_CONTROL | FIF_OTHER_BSS | \
        FIF_BCN_PRBRESP_PROMISC)

        struct ath5k_softc *sc = hw->priv;
        struct ath5k_hw *ah = sc->ah;
        u32 mfilt[2], rfilt;

        mutex_lock(&sc->lock);

        mfilt[0] = multicast;
        mfilt[1] = multicast >> 32;

        /* Only deal with supported flags */
        changed_flags &= SUPPORTED_FIF_FLAGS;
        *new_flags &= SUPPORTED_FIF_FLAGS;

        /* If HW detects any phy or radar errors, leave those filters on.
         * Also, always enable Unicast, Broadcasts and Multicast
         * XXX: move unicast, bssid broadcasts and multicast to mac80211 */
        rfilt = (ath5k_hw_get_rx_filter(ah) & (AR5K_RX_FILTER_PHYERR)) |
                (AR5K_RX_FILTER_UCAST | AR5K_RX_FILTER_BCAST |
                AR5K_RX_FILTER_MCAST);

        if (changed_flags & (FIF_PROMISC_IN_BSS | FIF_OTHER_BSS)) {
                if (*new_flags & FIF_PROMISC_IN_BSS)
                        __set_bit(ATH_STAT_PROMISC, sc->status);
                else
                        __clear_bit(ATH_STAT_PROMISC, sc->status);
        }

        if (test_bit(ATH_STAT_PROMISC, sc->status))
                rfilt |= AR5K_RX_FILTER_PROM;

        /* Note, AR5K_RX_FILTER_MCAST is already enabled */
        if (*new_flags & FIF_ALLMULTI) {
                mfilt[0] =  ~0;
                mfilt[1] =  ~0;
        }

        /* This is the best we can do */
        if (*new_flags & (FIF_FCSFAIL | FIF_PLCPFAIL))
                rfilt |= AR5K_RX_FILTER_PHYERR;

        /* FIF_BCN_PRBRESP_PROMISC really means to enable beacons
        * and probes for any BSSID */
        if ((*new_flags & FIF_BCN_PRBRESP_PROMISC) || (sc->nvifs > 1))
                rfilt |= AR5K_RX_FILTER_BEACON;

        /* FIF_CONTROL doc says that if FIF_PROMISC_IN_BSS is not
         * set we should only pass on control frames for this
         * station. This needs testing. I believe right now this
         * enables *all* control frames, which is OK.. but
         * but we should see if we can improve on granularity */
        if (*new_flags & FIF_CONTROL)
                rfilt |= AR5K_RX_FILTER_CONTROL;

        /* Additional settings per mode -- this is per ath5k */

        /* XXX move these to mac80211, and add a beacon IFF flag to mac80211 */

        switch (sc->opmode) {
        case NL80211_IFTYPE_MESH_POINT:
                rfilt |= AR5K_RX_FILTER_CONTROL |
                         AR5K_RX_FILTER_BEACON |
                         AR5K_RX_FILTER_PROBEREQ |
                         AR5K_RX_FILTER_PROM;
                break;
        case NL80211_IFTYPE_AP:
        case NL80211_IFTYPE_ADHOC:
                rfilt |= AR5K_RX_FILTER_PROBEREQ |
                         AR5K_RX_FILTER_BEACON;
                break;
        case NL80211_IFTYPE_STATION:
                if (sc->assoc)
                        rfilt |= AR5K_RX_FILTER_BEACON;
        default:
                break;
        }

        /* Set filters */
        ath5k_hw_set_rx_filter(ah, rfilt);

        /* Set multicast bits */
        ath5k_hw_set_mcast_filter(ah, mfilt[0], mfilt[1]);
        /* Set the cached hw filter flags, this will later actually
         * be set in HW */
        sc->filter_flags = rfilt;

        mutex_unlock(&sc->lock);
}


static int
ath5k_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 ath5k_softc *sc = hw->priv;
        struct ath5k_hw *ah = sc->ah;
        struct ath_common *common = ath5k_hw_common(ah);
        int ret = 0;

        if (ath5k_modparam_nohwcrypt)
                return -EOPNOTSUPP;

        switch (key->cipher) {
        case WLAN_CIPHER_SUITE_WEP40:
        case WLAN_CIPHER_SUITE_WEP104:
        case WLAN_CIPHER_SUITE_TKIP:
                break;
        case WLAN_CIPHER_SUITE_CCMP:
                if (common->crypt_caps & ATH_CRYPT_CAP_CIPHER_AESCCM)
                        break;
                return -EOPNOTSUPP;
        default:
                WARN_ON(1);
                return -EINVAL;
        }

        mutex_lock(&sc->lock);

        switch (cmd) {
        case SET_KEY:
                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 (key->cipher == WLAN_CIPHER_SUITE_CCMP)
                                key->flags |= IEEE80211_KEY_FLAG_SW_MGMT;
                        ret = 0;
                }
                break;
        case DISABLE_KEY:
                ath_key_delete(common, key);
                break;
        default:
                ret = -EINVAL;
        }

        mmiowb();
        mutex_unlock(&sc->lock);
        return ret;
}


static void
ath5k_sw_scan_start(struct ieee80211_hw *hw)
{
        struct ath5k_softc *sc = hw->priv;
        if (!sc->assoc)
                ath5k_hw_set_ledstate(sc->ah, AR5K_LED_SCAN);
}


static void
ath5k_sw_scan_complete(struct ieee80211_hw *hw)
{
        struct ath5k_softc *sc = hw->priv;
        ath5k_hw_set_ledstate(sc->ah, sc->assoc ?
                AR5K_LED_ASSOC : AR5K_LED_INIT);
}


static int
ath5k_get_stats(struct ieee80211_hw *hw,
                struct ieee80211_low_level_stats *stats)
{
        struct ath5k_softc *sc = hw->priv;

        /* Force update */
        ath5k_hw_update_mib_counters(sc->ah);

        stats->dot11ACKFailureCount = sc->stats.ack_fail;
        stats->dot11RTSFailureCount = sc->stats.rts_fail;
        stats->dot11RTSSuccessCount = sc->stats.rts_ok;
        stats->dot11FCSErrorCount = sc->stats.fcs_error;

        return 0;
}


static int
ath5k_conf_tx(struct ieee80211_hw *hw, u16 queue,
              const struct ieee80211_tx_queue_params *params)
{
        struct ath5k_softc *sc = hw->priv;
        struct ath5k_hw *ah = sc->ah;
        struct ath5k_txq_info qi;
        int ret = 0;

        if (queue >= ah->ah_capabilities.cap_queues.q_tx_num)
                return 0;

        mutex_lock(&sc->lock);

        ath5k_hw_get_tx_queueprops(ah, queue, &qi);

        qi.tqi_aifs = params->aifs;
        qi.tqi_cw_min = params->cw_min;
        qi.tqi_cw_max = params->cw_max;
        qi.tqi_burst_time = params->txop;

        ATH5K_DBG(sc, ATH5K_DEBUG_ANY,
                  "Configure tx [queue %d],  "
                  "aifs: %d, cw_min: %d, cw_max: %d, txop: %d\n",
                  queue, params->aifs, params->cw_min,
                  params->cw_max, params->txop);

        if (ath5k_hw_set_tx_queueprops(ah, queue, &qi)) {
                ATH5K_ERR(sc,
                          "Unable to update hardware queue %u!\n", queue);
                ret = -EIO;
        } else
                ath5k_hw_reset_tx_queue(ah, queue);

        mutex_unlock(&sc->lock);

        return ret;
}


static u64
ath5k_get_tsf(struct ieee80211_hw *hw)
{
        struct ath5k_softc *sc = hw->priv;

        return ath5k_hw_get_tsf64(sc->ah);
}


static void
ath5k_set_tsf(struct ieee80211_hw *hw, u64 tsf)
{
        struct ath5k_softc *sc = hw->priv;

        ath5k_hw_set_tsf64(sc->ah, tsf);
}


static void
ath5k_reset_tsf(struct ieee80211_hw *hw)
{
        struct ath5k_softc *sc = hw->priv;

        /*
         * in IBSS mode we need to update the beacon timers too.
         * this will also reset the TSF if we call it with 0
         */
        if (sc->opmode == NL80211_IFTYPE_ADHOC)
                ath5k_beacon_update_timers(sc, 0);
        else
                ath5k_hw_reset_tsf(sc->ah);
}


static int
ath5k_get_survey(struct ieee80211_hw *hw, int idx, struct survey_info *survey)
{
        struct ath5k_softc *sc = hw->priv;
        struct ieee80211_conf *conf = &hw->conf;
        struct ath_common *common = ath5k_hw_common(sc->ah);
        struct ath_cycle_counters *cc = &common->cc_survey;
        unsigned int div = common->clockrate * 1000;

        if (idx != 0)
                return -ENOENT;

        spin_lock_bh(&common->cc_lock);
        ath_hw_cycle_counters_update(common);
        if (cc->cycles > 0) {
                sc->survey.channel_time += cc->cycles / div;
                sc->survey.channel_time_busy += cc->rx_busy / div;
                sc->survey.channel_time_rx += cc->rx_frame / div;
                sc->survey.channel_time_tx += cc->tx_frame / div;
        }
        memset(cc, 0, sizeof(*cc));
        spin_unlock_bh(&common->cc_lock);

        memcpy(survey, &sc->survey, sizeof(*survey));

        survey->channel = conf->channel;
        survey->noise = sc->ah->ah_noise_floor;
        survey->filled = SURVEY_INFO_NOISE_DBM |
                        SURVEY_INFO_CHANNEL_TIME |
                        SURVEY_INFO_CHANNEL_TIME_BUSY |
                        SURVEY_INFO_CHANNEL_TIME_RX |
                        SURVEY_INFO_CHANNEL_TIME_TX;

        return 0;
}


/**
 * ath5k_set_coverage_class - Set IEEE 802.11 coverage class
 *
 * @hw: struct ieee80211_hw pointer
 * @coverage_class: IEEE 802.11 coverage class number
 *
 * Mac80211 callback. Sets slot time, ACK timeout and CTS timeout for given
 * coverage class. The values are persistent, they are restored after device
 * reset.
 */
static void
ath5k_set_coverage_class(struct ieee80211_hw *hw, u8 coverage_class)
{
        struct ath5k_softc *sc = hw->priv;

        mutex_lock(&sc->lock);
        ath5k_hw_set_coverage_class(sc->ah, coverage_class);
        mutex_unlock(&sc->lock);
}


static int
ath5k_set_antenna(struct ieee80211_hw *hw, u32 tx_ant, u32 rx_ant)
{
        struct ath5k_softc *sc = hw->priv;

        if (tx_ant == 1 && rx_ant == 1)
                ath5k_hw_set_antenna_mode(sc->ah, AR5K_ANTMODE_FIXED_A);
        else if (tx_ant == 2 && rx_ant == 2)
                ath5k_hw_set_antenna_mode(sc->ah, AR5K_ANTMODE_FIXED_B);
        else if ((tx_ant & 3) == 3 && (rx_ant & 3) == 3)
                ath5k_hw_set_antenna_mode(sc->ah, AR5K_ANTMODE_DEFAULT);
        else
                return -EINVAL;
        return 0;
}


static int
ath5k_get_antenna(struct ieee80211_hw *hw, u32 *tx_ant, u32 *rx_ant)
{
        struct ath5k_softc *sc = hw->priv;

        switch (sc->ah->ah_ant_mode) {
        case AR5K_ANTMODE_FIXED_A:
                *tx_ant = 1; *rx_ant = 1; break;
        case AR5K_ANTMODE_FIXED_B:
                *tx_ant = 2; *rx_ant = 2; break;
        case AR5K_ANTMODE_DEFAULT:
                *tx_ant = 3; *rx_ant = 3; break;
        }
        return 0;
}


const struct ieee80211_ops ath5k_hw_ops = {
        .tx                     = ath5k_tx,
        .start                  = ath5k_start,
        .stop                   = ath5k_stop,
        .add_interface          = ath5k_add_interface,
        /* .change_interface    = not implemented */
        .remove_interface       = ath5k_remove_interface,
        .config                 = ath5k_config,
        .bss_info_changed       = ath5k_bss_info_changed,
        .prepare_multicast      = ath5k_prepare_multicast,
        .configure_filter       = ath5k_configure_filter,
        /* .set_tim             = not implemented */
        .set_key                = ath5k_set_key,
        /* .update_tkip_key     = not implemented */
        /* .hw_scan             = not implemented */
        .sw_scan_start          = ath5k_sw_scan_start,
        .sw_scan_complete       = ath5k_sw_scan_complete,
        .get_stats              = ath5k_get_stats,
        /* .get_tkip_seq        = not implemented */
        /* .set_frag_threshold  = not implemented */
        /* .set_rts_threshold   = not implemented */
        /* .sta_add             = not implemented */
        /* .sta_remove          = not implemented */
        /* .sta_notify          = not implemented */
        .conf_tx                = ath5k_conf_tx,
        .get_tsf                = ath5k_get_tsf,
        .set_tsf                = ath5k_set_tsf,
        .reset_tsf              = ath5k_reset_tsf,
        /* .tx_last_beacon      = not implemented */
        /* .ampdu_action        = not needed */
        .get_survey             = ath5k_get_survey,
        .set_coverage_class     = ath5k_set_coverage_class,
        /* .rfkill_poll         = not implemented */
        /* .flush               = not implemented */
        /* .channel_switch      = not implemented */
        /* .napi_poll           = not implemented */
        .set_antenna            = ath5k_set_antenna,
        .get_antenna            = ath5k_get_antenna,
};