// SPDX-License-Identifier: GPL-2.0-only
/******************************************************************************
 *
 * Copyright(c) 2003 - 2014 Intel Corporation. All rights reserved.
 *
 * Portions of this file are derived from the ipw3945 project, as well
 * as portions of the ieee80211 subsystem header files.
 *
 * Contact Information:
 *  Intel Linux Wireless <linuxwifi@intel.com>
 * Intel Corporation, 5200 N.E. Elam Young Parkway, Hillsboro, OR 97124-6497
 *
 *****************************************************************************/
#include <linux/etherdevice.h>
#include <net/mac80211.h>
#include "iwl-trans.h"
#include "dev.h"
#include "agn.h"

const u8 iwl_bcast_addr[ETH_ALEN] = { 0xFF, 0xFF, 0xFF, 0xFF, 0xFF, 0xFF };

static int iwl_sta_ucode_activate(struct iwl_priv *priv, u8 sta_id)
{
        lockdep_assert_held(&priv->sta_lock);

        if (sta_id >= IWLAGN_STATION_COUNT) {
                IWL_ERR(priv, "invalid sta_id %u\n", sta_id);
                return -EINVAL;
        }
        if (!(priv->stations[sta_id].used & IWL_STA_DRIVER_ACTIVE))
                IWL_ERR(priv, "ACTIVATE a non DRIVER active station id %u "
                        "addr %pM\n",
                        sta_id, priv->stations[sta_id].sta.sta.addr);

        if (priv->stations[sta_id].used & IWL_STA_UCODE_ACTIVE) {
                IWL_DEBUG_ASSOC(priv,
                                "STA id %u addr %pM already present in uCode "
                                "(according to driver)\n",
                                sta_id, priv->stations[sta_id].sta.sta.addr);
        } else {
                priv->stations[sta_id].used |= IWL_STA_UCODE_ACTIVE;
                IWL_DEBUG_ASSOC(priv, "Added STA id %u addr %pM to uCode\n",
                                sta_id, priv->stations[sta_id].sta.sta.addr);
        }
        return 0;
}

static void iwl_process_add_sta_resp(struct iwl_priv *priv,
                                     struct iwl_rx_packet *pkt)
{
        struct iwl_add_sta_resp *add_sta_resp = (void *)pkt->data;

        IWL_DEBUG_INFO(priv, "Processing response for adding station\n");

        spin_lock_bh(&priv->sta_lock);

        switch (add_sta_resp->status) {
        case ADD_STA_SUCCESS_MSK:
                IWL_DEBUG_INFO(priv, "REPLY_ADD_STA PASSED\n");
                break;
        case ADD_STA_NO_ROOM_IN_TABLE:
                IWL_ERR(priv, "Adding station failed, no room in table.\n");
                break;
        case ADD_STA_NO_BLOCK_ACK_RESOURCE:
                IWL_ERR(priv,
                        "Adding station failed, no block ack resource.\n");
                break;
        case ADD_STA_MODIFY_NON_EXIST_STA:
                IWL_ERR(priv, "Attempting to modify non-existing station\n");
                break;
        default:
                IWL_DEBUG_ASSOC(priv, "Received REPLY_ADD_STA:(0x%08X)\n",
                                add_sta_resp->status);
                break;
        }

        spin_unlock_bh(&priv->sta_lock);
}

void iwl_add_sta_callback(struct iwl_priv *priv, struct iwl_rx_cmd_buffer *rxb)
{
        struct iwl_rx_packet *pkt = rxb_addr(rxb);

        iwl_process_add_sta_resp(priv, pkt);
}

int iwl_send_add_sta(struct iwl_priv *priv,
                     struct iwl_addsta_cmd *sta, u8 flags)
{
        int ret = 0;
        struct iwl_host_cmd cmd = {
                .id = REPLY_ADD_STA,
                .flags = flags,
                .data = { sta, },
                .len = { sizeof(*sta), },
        };
        u8 sta_id __maybe_unused = sta->sta.sta_id;
        struct iwl_rx_packet *pkt;
        struct iwl_add_sta_resp *add_sta_resp;

        IWL_DEBUG_INFO(priv, "Adding sta %u (%pM) %ssynchronously\n",
                       sta_id, sta->sta.addr, flags & CMD_ASYNC ?  "a" : "");

        if (!(flags & CMD_ASYNC)) {
                cmd.flags |= CMD_WANT_SKB;
                might_sleep();
        }

        ret = iwl_dvm_send_cmd(priv, &cmd);

        if (ret || (flags & CMD_ASYNC))
                return ret;

        pkt = cmd.resp_pkt;
        add_sta_resp = (void *)pkt->data;

        /* debug messages are printed in the handler */
        if (add_sta_resp->status == ADD_STA_SUCCESS_MSK) {
                spin_lock_bh(&priv->sta_lock);
                ret = iwl_sta_ucode_activate(priv, sta_id);
                spin_unlock_bh(&priv->sta_lock);
        } else {
                ret = -EIO;
        }

        iwl_free_resp(&cmd);

        return ret;
}

bool iwl_is_ht40_tx_allowed(struct iwl_priv *priv,
                            struct iwl_rxon_context *ctx,
                            struct ieee80211_sta *sta)
{
        if (!ctx->ht.enabled || !ctx->ht.is_40mhz)
                return false;

#ifdef CONFIG_IWLWIFI_DEBUGFS
        if (priv->disable_ht40)
                return false;
#endif

        /* special case for RXON */
        if (!sta)
                return true;

        return sta->bandwidth >= IEEE80211_STA_RX_BW_40;
}

static void iwl_sta_calc_ht_flags(struct iwl_priv *priv,
                                  struct ieee80211_sta *sta,
                                  struct iwl_rxon_context *ctx,
                                  __le32 *flags, __le32 *mask)
{
        struct ieee80211_sta_ht_cap *sta_ht_inf = &sta->ht_cap;

        *mask = STA_FLG_RTS_MIMO_PROT_MSK |
                STA_FLG_MIMO_DIS_MSK |
                STA_FLG_HT40_EN_MSK |
                STA_FLG_MAX_AGG_SIZE_MSK |
                STA_FLG_AGG_MPDU_DENSITY_MSK;
        *flags = 0;

        if (!sta || !sta_ht_inf->ht_supported)
                return;

        IWL_DEBUG_INFO(priv, "STA %pM SM PS mode: %s\n",
                        sta->addr,
                        (sta->smps_mode == IEEE80211_SMPS_STATIC) ?
                        "static" :
                        (sta->smps_mode == IEEE80211_SMPS_DYNAMIC) ?
                        "dynamic" : "disabled");

        switch (sta->smps_mode) {
        case IEEE80211_SMPS_STATIC:
                *flags |= STA_FLG_MIMO_DIS_MSK;
                break;
        case IEEE80211_SMPS_DYNAMIC:
                *flags |= STA_FLG_RTS_MIMO_PROT_MSK;
                break;
        case IEEE80211_SMPS_OFF:
                break;
        default:
                IWL_WARN(priv, "Invalid MIMO PS mode %d\n", sta->smps_mode);
                break;
        }

        *flags |= cpu_to_le32(
                (u32)sta_ht_inf->ampdu_factor << STA_FLG_MAX_AGG_SIZE_POS);

        *flags |= cpu_to_le32(
                (u32)sta_ht_inf->ampdu_density << STA_FLG_AGG_MPDU_DENSITY_POS);

        if (iwl_is_ht40_tx_allowed(priv, ctx, sta))
                *flags |= STA_FLG_HT40_EN_MSK;
}

int iwl_sta_update_ht(struct iwl_priv *priv, struct iwl_rxon_context *ctx,
                      struct ieee80211_sta *sta)
{
        u8 sta_id = iwl_sta_id(sta);
        __le32 flags, mask;
        struct iwl_addsta_cmd cmd;

        if (WARN_ON_ONCE(sta_id == IWL_INVALID_STATION))
                return -EINVAL;

        iwl_sta_calc_ht_flags(priv, sta, ctx, &flags, &mask);

        spin_lock_bh(&priv->sta_lock);
        priv->stations[sta_id].sta.station_flags &= ~mask;
        priv->stations[sta_id].sta.station_flags |= flags;
        spin_unlock_bh(&priv->sta_lock);

        memset(&cmd, 0, sizeof(cmd));
        cmd.mode = STA_CONTROL_MODIFY_MSK;
        cmd.station_flags_msk = mask;
        cmd.station_flags = flags;
        cmd.sta.sta_id = sta_id;

        return iwl_send_add_sta(priv, &cmd, 0);
}

static void iwl_set_ht_add_station(struct iwl_priv *priv, u8 index,
                                   struct ieee80211_sta *sta,
                                   struct iwl_rxon_context *ctx)
{
        __le32 flags, mask;

        iwl_sta_calc_ht_flags(priv, sta, ctx, &flags, &mask);

        lockdep_assert_held(&priv->sta_lock);
        priv->stations[index].sta.station_flags &= ~mask;
        priv->stations[index].sta.station_flags |= flags;
}

/**
 * iwl_prep_station - Prepare station information for addition
 *
 * should be called with sta_lock held
 */
u8 iwl_prep_station(struct iwl_priv *priv, struct iwl_rxon_context *ctx,
                    const u8 *addr, bool is_ap, struct ieee80211_sta *sta)
{
        struct iwl_station_entry *station;
        int i;
        u8 sta_id = IWL_INVALID_STATION;

        if (is_ap)
                sta_id = ctx->ap_sta_id;
        else if (is_broadcast_ether_addr(addr))
                sta_id = ctx->bcast_sta_id;
        else
                for (i = IWL_STA_ID; i < IWLAGN_STATION_COUNT; i++) {
                        if (ether_addr_equal(priv->stations[i].sta.sta.addr,
                                             addr)) {
                                sta_id = i;
                                break;
                        }

                        if (!priv->stations[i].used &&
                            sta_id == IWL_INVALID_STATION)
                                sta_id = i;
                }

        /*
         * These two conditions have the same outcome, but keep them
         * separate
         */
        if (unlikely(sta_id == IWL_INVALID_STATION))
                return sta_id;

        /*
         * uCode is not able to deal with multiple requests to add a
         * station. Keep track if one is in progress so that we do not send
         * another.
         */
        if (priv->stations[sta_id].used & IWL_STA_UCODE_INPROGRESS) {
                IWL_DEBUG_INFO(priv, "STA %d already in process of being "
                               "added.\n", sta_id);
                return sta_id;
        }

        if ((priv->stations[sta_id].used & IWL_STA_DRIVER_ACTIVE) &&
            (priv->stations[sta_id].used & IWL_STA_UCODE_ACTIVE) &&
            ether_addr_equal(priv->stations[sta_id].sta.sta.addr, addr)) {
                IWL_DEBUG_ASSOC(priv, "STA %d (%pM) already added, not "
                                "adding again.\n", sta_id, addr);
                return sta_id;
        }

        station = &priv->stations[sta_id];
        station->used = IWL_STA_DRIVER_ACTIVE;
        IWL_DEBUG_ASSOC(priv, "Add STA to driver ID %d: %pM\n",
                        sta_id, addr);
        priv->num_stations++;

        /* Set up the REPLY_ADD_STA command to send to device */
        memset(&station->sta, 0, sizeof(struct iwl_addsta_cmd));
        memcpy(station->sta.sta.addr, addr, ETH_ALEN);
        station->sta.mode = 0;
        station->sta.sta.sta_id = sta_id;
        station->sta.station_flags = ctx->station_flags;
        station->ctxid = ctx->ctxid;

        if (sta) {
                struct iwl_station_priv *sta_priv;

                sta_priv = (void *)sta->drv_priv;
                sta_priv->ctx = ctx;
        }

        /*
         * OK to call unconditionally, since local stations (IBSS BSSID
         * STA and broadcast STA) pass in a NULL sta, and mac80211
         * doesn't allow HT IBSS.
         */
        iwl_set_ht_add_station(priv, sta_id, sta, ctx);

        return sta_id;

}

#define STA_WAIT_TIMEOUT (HZ/2)

/**
 * iwl_add_station_common -
 */
int iwl_add_station_common(struct iwl_priv *priv, struct iwl_rxon_context *ctx,
                           const u8 *addr, bool is_ap,
                           struct ieee80211_sta *sta, u8 *sta_id_r)
{
        int ret = 0;
        u8 sta_id;
        struct iwl_addsta_cmd sta_cmd;

        *sta_id_r = 0;
        spin_lock_bh(&priv->sta_lock);
        sta_id = iwl_prep_station(priv, ctx, addr, is_ap, sta);
        if (sta_id == IWL_INVALID_STATION) {
                IWL_ERR(priv, "Unable to prepare station %pM for addition\n",
                        addr);
                spin_unlock_bh(&priv->sta_lock);
                return -EINVAL;
        }

        /*
         * uCode is not able to deal with multiple requests to add a
         * station. Keep track if one is in progress so that we do not send
         * another.
         */
        if (priv->stations[sta_id].used & IWL_STA_UCODE_INPROGRESS) {
                IWL_DEBUG_INFO(priv, "STA %d already in process of being "
                               "added.\n", sta_id);
                spin_unlock_bh(&priv->sta_lock);
                return -EEXIST;
        }

        if ((priv->stations[sta_id].used & IWL_STA_DRIVER_ACTIVE) &&
            (priv->stations[sta_id].used & IWL_STA_UCODE_ACTIVE)) {
                IWL_DEBUG_ASSOC(priv, "STA %d (%pM) already added, not "
                                "adding again.\n", sta_id, addr);
                spin_unlock_bh(&priv->sta_lock);
                return -EEXIST;
        }

        priv->stations[sta_id].used |= IWL_STA_UCODE_INPROGRESS;
        memcpy(&sta_cmd, &priv->stations[sta_id].sta,
               sizeof(struct iwl_addsta_cmd));
        spin_unlock_bh(&priv->sta_lock);

        /* Add station to device's station table */
        ret = iwl_send_add_sta(priv, &sta_cmd, 0);
        if (ret) {
                spin_lock_bh(&priv->sta_lock);
                IWL_ERR(priv, "Adding station %pM failed.\n",
                        priv->stations[sta_id].sta.sta.addr);
                priv->stations[sta_id].used &= ~IWL_STA_DRIVER_ACTIVE;
                priv->stations[sta_id].used &= ~IWL_STA_UCODE_INPROGRESS;
                spin_unlock_bh(&priv->sta_lock);
        }
        *sta_id_r = sta_id;
        return ret;
}

/**
 * iwl_sta_ucode_deactivate - deactivate ucode status for a station
 */
static void iwl_sta_ucode_deactivate(struct iwl_priv *priv, u8 sta_id)
{
        lockdep_assert_held(&priv->sta_lock);

        /* Ucode must be active and driver must be non active */
        if ((priv->stations[sta_id].used &
             (IWL_STA_UCODE_ACTIVE | IWL_STA_DRIVER_ACTIVE)) !=
              IWL_STA_UCODE_ACTIVE)
                IWL_ERR(priv, "removed non active STA %u\n", sta_id);

        priv->stations[sta_id].used &= ~IWL_STA_UCODE_ACTIVE;

        memset(&priv->stations[sta_id], 0, sizeof(struct iwl_station_entry));
        IWL_DEBUG_ASSOC(priv, "Removed STA %u\n", sta_id);
}

static int iwl_send_remove_station(struct iwl_priv *priv,
                                   const u8 *addr, int sta_id,
                                   bool temporary)
{
        struct iwl_rx_packet *pkt;
        int ret;
        struct iwl_rem_sta_cmd rm_sta_cmd;
        struct iwl_rem_sta_resp *rem_sta_resp;

        struct iwl_host_cmd cmd = {
                .id = REPLY_REMOVE_STA,
                .len = { sizeof(struct iwl_rem_sta_cmd), },
                .data = { &rm_sta_cmd, },
        };

        memset(&rm_sta_cmd, 0, sizeof(rm_sta_cmd));
        rm_sta_cmd.num_sta = 1;
        memcpy(&rm_sta_cmd.addr, addr, ETH_ALEN);

        cmd.flags |= CMD_WANT_SKB;

        ret = iwl_dvm_send_cmd(priv, &cmd);

        if (ret)
                return ret;

        pkt = cmd.resp_pkt;
        rem_sta_resp = (void *)pkt->data;

        switch (rem_sta_resp->status) {
        case REM_STA_SUCCESS_MSK:
                if (!temporary) {
                        spin_lock_bh(&priv->sta_lock);
                        iwl_sta_ucode_deactivate(priv, sta_id);
                        spin_unlock_bh(&priv->sta_lock);
                }
                IWL_DEBUG_ASSOC(priv, "REPLY_REMOVE_STA PASSED\n");
                break;
        default:
                ret = -EIO;
                IWL_ERR(priv, "REPLY_REMOVE_STA failed\n");
                break;
        }

        iwl_free_resp(&cmd);

        return ret;
}

/**
 * iwl_remove_station - Remove driver's knowledge of station.
 */
int iwl_remove_station(struct iwl_priv *priv, const u8 sta_id,
                       const u8 *addr)
{
        u8 tid;

        if (!iwl_is_ready(priv)) {
                IWL_DEBUG_INFO(priv,
                        "Unable to remove station %pM, device not ready.\n",
                        addr);
                /*
                 * It is typical for stations to be removed when we are
                 * going down. Return success since device will be down
                 * soon anyway
                 */
                return 0;
        }

        IWL_DEBUG_ASSOC(priv, "Removing STA from driver:%d  %pM\n",
                        sta_id, addr);

        if (WARN_ON(sta_id == IWL_INVALID_STATION))
                return -EINVAL;

        spin_lock_bh(&priv->sta_lock);

        if (!(priv->stations[sta_id].used & IWL_STA_DRIVER_ACTIVE)) {
                IWL_DEBUG_INFO(priv, "Removing %pM but non DRIVER active\n",
                                addr);
                goto out_err;
        }

        if (!(priv->stations[sta_id].used & IWL_STA_UCODE_ACTIVE)) {
                IWL_DEBUG_INFO(priv, "Removing %pM but non UCODE active\n",
                                addr);
                goto out_err;
        }

        if (priv->stations[sta_id].used & IWL_STA_LOCAL) {
                kfree(priv->stations[sta_id].lq);
                priv->stations[sta_id].lq = NULL;
        }

        for (tid = 0; tid < IWL_MAX_TID_COUNT; tid++)
                memset(&priv->tid_data[sta_id][tid], 0,
                        sizeof(priv->tid_data[sta_id][tid]));

        priv->stations[sta_id].used &= ~IWL_STA_DRIVER_ACTIVE;

        priv->num_stations--;

        if (WARN_ON(priv->num_stations < 0))
                priv->num_stations = 0;

        spin_unlock_bh(&priv->sta_lock);

        return iwl_send_remove_station(priv, addr, sta_id, false);
out_err:
        spin_unlock_bh(&priv->sta_lock);
        return -EINVAL;
}

void iwl_deactivate_station(struct iwl_priv *priv, const u8 sta_id,
                            const u8 *addr)
{
        u8 tid;

        if (!iwl_is_ready(priv)) {
                IWL_DEBUG_INFO(priv,
                        "Unable to remove station %pM, device not ready.\n",
                        addr);
                return;
        }

        IWL_DEBUG_ASSOC(priv, "Deactivating STA: %pM (%d)\n", addr, sta_id);

        if (WARN_ON_ONCE(sta_id == IWL_INVALID_STATION))
                return;

        spin_lock_bh(&priv->sta_lock);

        WARN_ON_ONCE(!(priv->stations[sta_id].used & IWL_STA_DRIVER_ACTIVE));

        for (tid = 0; tid < IWL_MAX_TID_COUNT; tid++)
                memset(&priv->tid_data[sta_id][tid], 0,
                        sizeof(priv->tid_data[sta_id][tid]));

        priv->stations[sta_id].used &= ~IWL_STA_DRIVER_ACTIVE;
        priv->stations[sta_id].used &= ~IWL_STA_UCODE_INPROGRESS;

        priv->num_stations--;

        if (WARN_ON_ONCE(priv->num_stations < 0))
                priv->num_stations = 0;

        spin_unlock_bh(&priv->sta_lock);
}

static void iwl_sta_fill_lq(struct iwl_priv *priv, struct iwl_rxon_context *ctx,
                            u8 sta_id, struct iwl_link_quality_cmd *link_cmd)
{
        int i, r;
        u32 rate_flags = 0;
        __le32 rate_n_flags;

        lockdep_assert_held(&priv->mutex);

        memset(link_cmd, 0, sizeof(*link_cmd));

        /* Set up the rate scaling to start at selected rate, fall back
         * all the way down to 1M in IEEE order, and then spin on 1M */
        if (priv->band == NL80211_BAND_5GHZ)
                r = IWL_RATE_6M_INDEX;
        else if (ctx && ctx->vif && ctx->vif->p2p)
                r = IWL_RATE_6M_INDEX;
        else
                r = IWL_RATE_1M_INDEX;

        if (r >= IWL_FIRST_CCK_RATE && r <= IWL_LAST_CCK_RATE)
                rate_flags |= RATE_MCS_CCK_MSK;

        rate_flags |= first_antenna(priv->nvm_data->valid_tx_ant) <<
                                RATE_MCS_ANT_POS;
        rate_n_flags = iwl_hw_set_rate_n_flags(iwl_rates[r].plcp, rate_flags);
        for (i = 0; i < LINK_QUAL_MAX_RETRY_NUM; i++)
                link_cmd->rs_table[i].rate_n_flags = rate_n_flags;

        link_cmd->general_params.single_stream_ant_msk =
                        first_antenna(priv->nvm_data->valid_tx_ant);

        link_cmd->general_params.dual_stream_ant_msk =
                priv->nvm_data->valid_tx_ant &
                ~first_antenna(priv->nvm_data->valid_tx_ant);
        if (!link_cmd->general_params.dual_stream_ant_msk) {
                link_cmd->general_params.dual_stream_ant_msk = ANT_AB;
        } else if (num_of_ant(priv->nvm_data->valid_tx_ant) == 2) {
                link_cmd->general_params.dual_stream_ant_msk =
                        priv->nvm_data->valid_tx_ant;
        }

        link_cmd->agg_params.agg_dis_start_th =
                LINK_QUAL_AGG_DISABLE_START_DEF;
        link_cmd->agg_params.agg_time_limit =
                cpu_to_le16(LINK_QUAL_AGG_TIME_LIMIT_DEF);

        link_cmd->sta_id = sta_id;
}

/**
 * iwl_clear_ucode_stations - clear ucode station table bits
 *
 * This function clears all the bits in the driver indicating
 * which stations are active in the ucode. Call when something
 * other than explicit station management would cause this in
 * the ucode, e.g. unassociated RXON.
 */
void iwl_clear_ucode_stations(struct iwl_priv *priv,
                              struct iwl_rxon_context *ctx)
{
        int i;
        bool cleared = false;

        IWL_DEBUG_INFO(priv, "Clearing ucode stations in driver\n");

        spin_lock_bh(&priv->sta_lock);
        for (i = 0; i < IWLAGN_STATION_COUNT; i++) {
                if (ctx && ctx->ctxid != priv->stations[i].ctxid)
                        continue;

                if (priv->stations[i].used & IWL_STA_UCODE_ACTIVE) {
                        IWL_DEBUG_INFO(priv,
                                "Clearing ucode active for station %d\n", i);
                        priv->stations[i].used &= ~IWL_STA_UCODE_ACTIVE;
                        cleared = true;
                }
        }
        spin_unlock_bh(&priv->sta_lock);

        if (!cleared)
                IWL_DEBUG_INFO(priv,
                               "No active stations found to be cleared\n");
}

/**
 * iwl_restore_stations() - Restore driver known stations to device
 *
 * All stations considered active by driver, but not present in ucode, is
 * restored.
 *
 * Function sleeps.
 */
void iwl_restore_stations(struct iwl_priv *priv, struct iwl_rxon_context *ctx)
{
        struct iwl_addsta_cmd sta_cmd;
        static const struct iwl_link_quality_cmd zero_lq = {};
        struct iwl_link_quality_cmd lq;
        int i;
        bool found = false;
        int ret;
        bool send_lq;

        if (!iwl_is_ready(priv)) {
                IWL_DEBUG_INFO(priv,
                               "Not ready yet, not restoring any stations.\n");
                return;
        }

        IWL_DEBUG_ASSOC(priv, "Restoring all known stations ... start.\n");
        spin_lock_bh(&priv->sta_lock);
        for (i = 0; i < IWLAGN_STATION_COUNT; i++) {
                if (ctx->ctxid != priv->stations[i].ctxid)
                        continue;
                if ((priv->stations[i].used & IWL_STA_DRIVER_ACTIVE) &&
                            !(priv->stations[i].used & IWL_STA_UCODE_ACTIVE)) {
                        IWL_DEBUG_ASSOC(priv, "Restoring sta %pM\n",
                                        priv->stations[i].sta.sta.addr);
                        priv->stations[i].sta.mode = 0;
                        priv->stations[i].used |= IWL_STA_UCODE_INPROGRESS;
                        found = true;
                }
        }

        for (i = 0; i < IWLAGN_STATION_COUNT; i++) {
                if ((priv->stations[i].used & IWL_STA_UCODE_INPROGRESS)) {
                        memcpy(&sta_cmd, &priv->stations[i].sta,
                               sizeof(struct iwl_addsta_cmd));
                        send_lq = false;
                        if (priv->stations[i].lq) {
                                if (priv->wowlan)
                                        iwl_sta_fill_lq(priv, ctx, i, &lq);
                                else
                                        memcpy(&lq, priv->stations[i].lq,
                                               sizeof(struct iwl_link_quality_cmd));

                                if (memcmp(&lq, &zero_lq, sizeof(lq)))
                                        send_lq = true;
                        }
                        spin_unlock_bh(&priv->sta_lock);
                        ret = iwl_send_add_sta(priv, &sta_cmd, 0);
                        if (ret) {
                                spin_lock_bh(&priv->sta_lock);
                                IWL_ERR(priv, "Adding station %pM failed.\n",
                                        priv->stations[i].sta.sta.addr);
                                priv->stations[i].used &=
                                                ~IWL_STA_DRIVER_ACTIVE;
                                priv->stations[i].used &=
                                                ~IWL_STA_UCODE_INPROGRESS;
                                continue;
                        }
                        /*
                         * Rate scaling has already been initialized, send
                         * current LQ command
                         */
                        if (send_lq)
                                iwl_send_lq_cmd(priv, ctx, &lq, 0, true);
                        spin_lock_bh(&priv->sta_lock);
                        priv->stations[i].used &= ~IWL_STA_UCODE_INPROGRESS;
                }
        }

        spin_unlock_bh(&priv->sta_lock);
        if (!found)
                IWL_DEBUG_INFO(priv, "Restoring all known stations .... "
                        "no stations to be restored.\n");
        else
                IWL_DEBUG_INFO(priv, "Restoring all known stations .... "
                        "complete.\n");
}

int iwl_get_free_ucode_key_offset(struct iwl_priv *priv)
{
        int i;

        for (i = 0; i < priv->sta_key_max_num; i++)
                if (!test_and_set_bit(i, &priv->ucode_key_table))
                        return i;

        return WEP_INVALID_OFFSET;
}

void iwl_dealloc_bcast_stations(struct iwl_priv *priv)
{
        int i;

        spin_lock_bh(&priv->sta_lock);
        for (i = 0; i < IWLAGN_STATION_COUNT; i++) {
                if (!(priv->stations[i].used & IWL_STA_BCAST))
                        continue;

                priv->stations[i].used &= ~IWL_STA_UCODE_ACTIVE;
                priv->num_stations--;
                if (WARN_ON(priv->num_stations < 0))
                        priv->num_stations = 0;
                kfree(priv->stations[i].lq);
                priv->stations[i].lq = NULL;
        }
        spin_unlock_bh(&priv->sta_lock);
}

#ifdef CONFIG_IWLWIFI_DEBUG
static void iwl_dump_lq_cmd(struct iwl_priv *priv,
                           struct iwl_link_quality_cmd *lq)
{
        int i;
        IWL_DEBUG_RATE(priv, "lq station id 0x%x\n", lq->sta_id);
        IWL_DEBUG_RATE(priv, "lq ant 0x%X 0x%X\n",
                       lq->general_params.single_stream_ant_msk,
                       lq->general_params.dual_stream_ant_msk);

        for (i = 0; i < LINK_QUAL_MAX_RETRY_NUM; i++)
                IWL_DEBUG_RATE(priv, "lq index %d 0x%X\n",
                               i, lq->rs_table[i].rate_n_flags);
}
#else
static inline void iwl_dump_lq_cmd(struct iwl_priv *priv,
                                   struct iwl_link_quality_cmd *lq)
{
}
#endif

/**
 * is_lq_table_valid() - Test one aspect of LQ cmd for validity
 *
 * It sometimes happens when a HT rate has been in use and we
 * loose connectivity with AP then mac80211 will first tell us that the
 * current channel is not HT anymore before removing the station. In such a
 * scenario the RXON flags will be updated to indicate we are not
 * communicating HT anymore, but the LQ command may still contain HT rates.
 * Test for this to prevent driver from sending LQ command between the time
 * RXON flags are updated and when LQ command is updated.
 */
static bool is_lq_table_valid(struct iwl_priv *priv,
                              struct iwl_rxon_context *ctx,
                              struct iwl_link_quality_cmd *lq)
{
        int i;

        if (ctx->ht.enabled)
                return true;

        IWL_DEBUG_INFO(priv, "Channel %u is not an HT channel\n",
                       ctx->active.channel);
        for (i = 0; i < LINK_QUAL_MAX_RETRY_NUM; i++) {
                if (le32_to_cpu(lq->rs_table[i].rate_n_flags) &
                    RATE_MCS_HT_MSK) {
                        IWL_DEBUG_INFO(priv,
                                       "index %d of LQ expects HT channel\n",
                                       i);
                        return false;
                }
        }
        return true;
}

/**
 * iwl_send_lq_cmd() - Send link quality command
 * @init: This command is sent as part of station initialization right
 *        after station has been added.
 *
 * The link quality command is sent as the last step of station creation.
 * This is the special case in which init is set and we call a callback in
 * this case to clear the state indicating that station creation is in
 * progress.
 */
int iwl_send_lq_cmd(struct iwl_priv *priv, struct iwl_rxon_context *ctx,
                    struct iwl_link_quality_cmd *lq, u8 flags, bool init)
{
        int ret = 0;
        struct iwl_host_cmd cmd = {
                .id = REPLY_TX_LINK_QUALITY_CMD,
                .len = { sizeof(struct iwl_link_quality_cmd), },
                .flags = flags,
                .data = { lq, },
        };

        if (WARN_ON(lq->sta_id == IWL_INVALID_STATION))
                return -EINVAL;


        spin_lock_bh(&priv->sta_lock);
        if (!(priv->stations[lq->sta_id].used & IWL_STA_DRIVER_ACTIVE)) {
                spin_unlock_bh(&priv->sta_lock);
                return -EINVAL;
        }
        spin_unlock_bh(&priv->sta_lock);

        iwl_dump_lq_cmd(priv, lq);
        if (WARN_ON(init && (cmd.flags & CMD_ASYNC)))
                return -EINVAL;

        if (is_lq_table_valid(priv, ctx, lq))
                ret = iwl_dvm_send_cmd(priv, &cmd);
        else
                ret = -EINVAL;

        if (cmd.flags & CMD_ASYNC)
                return ret;

        if (init) {
                IWL_DEBUG_INFO(priv, "init LQ command complete, "
                               "clearing sta addition status for sta %d\n",
                               lq->sta_id);
                spin_lock_bh(&priv->sta_lock);
                priv->stations[lq->sta_id].used &= ~IWL_STA_UCODE_INPROGRESS;
                spin_unlock_bh(&priv->sta_lock);
        }
        return ret;
}


static struct iwl_link_quality_cmd *
iwl_sta_alloc_lq(struct iwl_priv *priv, struct iwl_rxon_context *ctx,
                 u8 sta_id)
{
        struct iwl_link_quality_cmd *link_cmd;

        link_cmd = kzalloc(sizeof(struct iwl_link_quality_cmd), GFP_KERNEL);
        if (!link_cmd) {
                IWL_ERR(priv, "Unable to allocate memory for LQ cmd.\n");
                return NULL;
        }

        iwl_sta_fill_lq(priv, ctx, sta_id, link_cmd);

        return link_cmd;
}

/*
 * iwlagn_add_bssid_station - Add the special IBSS BSSID station
 *
 * Function sleeps.
 */
int iwlagn_add_bssid_station(struct iwl_priv *priv,
                             struct iwl_rxon_context *ctx,
                             const u8 *addr, u8 *sta_id_r)
{
        int ret;
        u8 sta_id;
        struct iwl_link_quality_cmd *link_cmd;

        if (sta_id_r)
                *sta_id_r = IWL_INVALID_STATION;

        ret = iwl_add_station_common(priv, ctx, addr, 0, NULL, &sta_id);
        if (ret) {
                IWL_ERR(priv, "Unable to add station %pM\n", addr);
                return ret;
        }

        if (sta_id_r)
                *sta_id_r = sta_id;

        spin_lock_bh(&priv->sta_lock);
        priv->stations[sta_id].used |= IWL_STA_LOCAL;
        spin_unlock_bh(&priv->sta_lock);

        /* Set up default rate scaling table in device's station table */
        link_cmd = iwl_sta_alloc_lq(priv, ctx, sta_id);
        if (!link_cmd) {
                IWL_ERR(priv,
                        "Unable to initialize rate scaling for station %pM.\n",
                        addr);
                return -ENOMEM;
        }

        ret = iwl_send_lq_cmd(priv, ctx, link_cmd, 0, true);
        if (ret)
                IWL_ERR(priv, "Link quality command failed (%d)\n", ret);

        spin_lock_bh(&priv->sta_lock);
        priv->stations[sta_id].lq = link_cmd;
        spin_unlock_bh(&priv->sta_lock);

        return 0;
}

/*
 * static WEP keys
 *
 * For each context, the device has a table of 4 static WEP keys
 * (one for each key index) that is updated with the following
 * commands.
 */

static int iwl_send_static_wepkey_cmd(struct iwl_priv *priv,
                                      struct iwl_rxon_context *ctx,
                                      bool send_if_empty)
{
        int i, not_empty = 0;
        u8 buff[sizeof(struct iwl_wep_cmd) +
                sizeof(struct iwl_wep_key) * WEP_KEYS_MAX];
        struct iwl_wep_cmd *wep_cmd = (struct iwl_wep_cmd *)buff;
        size_t cmd_size  = sizeof(struct iwl_wep_cmd);
        struct iwl_host_cmd cmd = {
                .id = ctx->wep_key_cmd,
                .data = { wep_cmd, },
        };

        might_sleep();

        memset(wep_cmd, 0, cmd_size +
                        (sizeof(struct iwl_wep_key) * WEP_KEYS_MAX));

        for (i = 0; i < WEP_KEYS_MAX ; i++) {
                wep_cmd->key[i].key_index = i;
                if (ctx->wep_keys[i].key_size) {
                        wep_cmd->key[i].key_offset = i;
                        not_empty = 1;
                } else {
                        wep_cmd->key[i].key_offset = WEP_INVALID_OFFSET;
                }

                wep_cmd->key[i].key_size = ctx->wep_keys[i].key_size;
                memcpy(&wep_cmd->key[i].key[3], ctx->wep_keys[i].key,
                                ctx->wep_keys[i].key_size);
        }

        wep_cmd->global_key_type = WEP_KEY_WEP_TYPE;
        wep_cmd->num_keys = WEP_KEYS_MAX;

        cmd_size += sizeof(struct iwl_wep_key) * WEP_KEYS_MAX;

        cmd.len[0] = cmd_size;

        if (not_empty || send_if_empty)
                return iwl_dvm_send_cmd(priv, &cmd);
        else
                return 0;
}

int iwl_restore_default_wep_keys(struct iwl_priv *priv,
                                 struct iwl_rxon_context *ctx)
{
        lockdep_assert_held(&priv->mutex);

        return iwl_send_static_wepkey_cmd(priv, ctx, false);
}

int iwl_remove_default_wep_key(struct iwl_priv *priv,
                               struct iwl_rxon_context *ctx,
                               struct ieee80211_key_conf *keyconf)
{
        int ret;

        lockdep_assert_held(&priv->mutex);

        IWL_DEBUG_WEP(priv, "Removing default WEP key: idx=%d\n",
                      keyconf->keyidx);

        memset(&ctx->wep_keys[keyconf->keyidx], 0, sizeof(ctx->wep_keys[0]));
        if (iwl_is_rfkill(priv)) {
                IWL_DEBUG_WEP(priv,
                        "Not sending REPLY_WEPKEY command due to RFKILL.\n");
                /* but keys in device are clear anyway so return success */
                return 0;
        }
        ret = iwl_send_static_wepkey_cmd(priv, ctx, 1);
        IWL_DEBUG_WEP(priv, "Remove default WEP key: idx=%d ret=%d\n",
                      keyconf->keyidx, ret);

        return ret;
}

int iwl_set_default_wep_key(struct iwl_priv *priv,
                            struct iwl_rxon_context *ctx,
                            struct ieee80211_key_conf *keyconf)
{
        int ret;

        lockdep_assert_held(&priv->mutex);

        if (keyconf->keylen != WEP_KEY_LEN_128 &&
            keyconf->keylen != WEP_KEY_LEN_64) {
                IWL_DEBUG_WEP(priv,
                              "Bad WEP key length %d\n", keyconf->keylen);
                return -EINVAL;
        }

        keyconf->hw_key_idx = IWLAGN_HW_KEY_DEFAULT;

        ctx->wep_keys[keyconf->keyidx].key_size = keyconf->keylen;
        memcpy(&ctx->wep_keys[keyconf->keyidx].key, &keyconf->key,
                                                        keyconf->keylen);

        ret = iwl_send_static_wepkey_cmd(priv, ctx, false);
        IWL_DEBUG_WEP(priv, "Set default WEP key: len=%d idx=%d ret=%d\n",
                keyconf->keylen, keyconf->keyidx, ret);

        return ret;
}

/*
 * dynamic (per-station) keys
 *
 * The dynamic keys are a little more complicated. The device has
 * a key cache of up to STA_KEY_MAX_NUM/STA_KEY_MAX_NUM_PAN keys.
 * These are linked to stations by a table that contains an index
 * into the key table for each station/key index/{mcast,unicast},
 * i.e. it's basically an array of pointers like this:
 *      key_offset_t key_mapping[NUM_STATIONS][4][2];
 * (it really works differently, but you can think of it as such)
 *
 * The key uploading and linking happens in the same command, the
 * add station command with STA_MODIFY_KEY_MASK.
 */

static u8 iwlagn_key_sta_id(struct iwl_priv *priv,
                            struct ieee80211_vif *vif,
                            struct ieee80211_sta *sta)
{
        struct iwl_vif_priv *vif_priv = (void *)vif->drv_priv;

        if (sta)
                return iwl_sta_id(sta);

        /*
         * The device expects GTKs for station interfaces to be
         * installed as GTKs for the AP station. If we have no
         * station ID, then use the ap_sta_id in that case.
         */
        if (vif->type == NL80211_IFTYPE_STATION && vif_priv->ctx)
                return vif_priv->ctx->ap_sta_id;

        return IWL_INVALID_STATION;
}

static int iwlagn_send_sta_key(struct iwl_priv *priv,
                               struct ieee80211_key_conf *keyconf,
                               u8 sta_id, u32 tkip_iv32, u16 *tkip_p1k,
                               u32 cmd_flags)
{
        __le16 key_flags;
        struct iwl_addsta_cmd sta_cmd;
        int i;

        spin_lock_bh(&priv->sta_lock);
        memcpy(&sta_cmd, &priv->stations[sta_id].sta, sizeof(sta_cmd));
        spin_unlock_bh(&priv->sta_lock);

        key_flags = cpu_to_le16(keyconf->keyidx << STA_KEY_FLG_KEYID_POS);
        key_flags |= STA_KEY_FLG_MAP_KEY_MSK;

        switch (keyconf->cipher) {
        case WLAN_CIPHER_SUITE_CCMP:
                key_flags |= STA_KEY_FLG_CCMP;
                memcpy(sta_cmd.key.key, keyconf->key, keyconf->keylen);
                break;
        case WLAN_CIPHER_SUITE_TKIP:
                key_flags |= STA_KEY_FLG_TKIP;
                sta_cmd.key.tkip_rx_tsc_byte2 = tkip_iv32;
                for (i = 0; i < 5; i++)
                        sta_cmd.key.tkip_rx_ttak[i] = cpu_to_le16(tkip_p1k[i]);
                memcpy(sta_cmd.key.key, keyconf->key, keyconf->keylen);
                break;
        case WLAN_CIPHER_SUITE_WEP104:
                key_flags |= STA_KEY_FLG_KEY_SIZE_MSK;
                /* fall through */
        case WLAN_CIPHER_SUITE_WEP40:
                key_flags |= STA_KEY_FLG_WEP;
                memcpy(&sta_cmd.key.key[3], keyconf->key, keyconf->keylen);
                break;
        default:
                WARN_ON(1);
                return -EINVAL;
        }

        if (!(keyconf->flags & IEEE80211_KEY_FLAG_PAIRWISE))
                key_flags |= STA_KEY_MULTICAST_MSK;

        /* key pointer (offset) */
        sta_cmd.key.key_offset = keyconf->hw_key_idx;

        sta_cmd.key.key_flags = key_flags;
        sta_cmd.mode = STA_CONTROL_MODIFY_MSK;
        sta_cmd.sta.modify_mask = STA_MODIFY_KEY_MASK;

        return iwl_send_add_sta(priv, &sta_cmd, cmd_flags);
}

void iwl_update_tkip_key(struct iwl_priv *priv,
                         struct ieee80211_vif *vif,
                         struct ieee80211_key_conf *keyconf,
                         struct ieee80211_sta *sta, u32 iv32, u16 *phase1key)
{
        u8 sta_id = iwlagn_key_sta_id(priv, vif, sta);

        if (sta_id == IWL_INVALID_STATION)
                return;

        if (iwl_scan_cancel(priv)) {
                /* cancel scan failed, just live w/ bad key and rely
                   briefly on SW decryption */
                return;
        }

        iwlagn_send_sta_key(priv, keyconf, sta_id,
                            iv32, phase1key, CMD_ASYNC);
}

int iwl_remove_dynamic_key(struct iwl_priv *priv,
                           struct iwl_rxon_context *ctx,
                           struct ieee80211_key_conf *keyconf,
                           struct ieee80211_sta *sta)
{
        struct iwl_addsta_cmd sta_cmd;
        u8 sta_id = iwlagn_key_sta_id(priv, ctx->vif, sta);
        __le16 key_flags;

        /* if station isn't there, neither is the key */
        if (sta_id == IWL_INVALID_STATION)
                return -ENOENT;

        spin_lock_bh(&priv->sta_lock);
        memcpy(&sta_cmd, &priv->stations[sta_id].sta, sizeof(sta_cmd));
        if (!(priv->stations[sta_id].used & IWL_STA_UCODE_ACTIVE))
                sta_id = IWL_INVALID_STATION;
        spin_unlock_bh(&priv->sta_lock);

        if (sta_id == IWL_INVALID_STATION)
                return 0;

        lockdep_assert_held(&priv->mutex);

        ctx->key_mapping_keys--;

        IWL_DEBUG_WEP(priv, "Remove dynamic key: idx=%d sta=%d\n",
                      keyconf->keyidx, sta_id);

        if (!test_and_clear_bit(keyconf->hw_key_idx, &priv->ucode_key_table))
                IWL_ERR(priv, "offset %d not used in uCode key table.\n",
                        keyconf->hw_key_idx);

        key_flags = cpu_to_le16(keyconf->keyidx << STA_KEY_FLG_KEYID_POS);
        key_flags |= STA_KEY_FLG_MAP_KEY_MSK | STA_KEY_FLG_NO_ENC |
                     STA_KEY_FLG_INVALID;

        if (!(keyconf->flags & IEEE80211_KEY_FLAG_PAIRWISE))
                key_flags |= STA_KEY_MULTICAST_MSK;

        sta_cmd.key.key_flags = key_flags;
        sta_cmd.key.key_offset = keyconf->hw_key_idx;
        sta_cmd.sta.modify_mask = STA_MODIFY_KEY_MASK;
        sta_cmd.mode = STA_CONTROL_MODIFY_MSK;

        return iwl_send_add_sta(priv, &sta_cmd, 0);
}

int iwl_set_dynamic_key(struct iwl_priv *priv,
                        struct iwl_rxon_context *ctx,
                        struct ieee80211_key_conf *keyconf,
                        struct ieee80211_sta *sta)
{
        struct ieee80211_key_seq seq;
        u16 p1k[5];
        int ret;
        u8 sta_id = iwlagn_key_sta_id(priv, ctx->vif, sta);
        const u8 *addr;

        if (sta_id == IWL_INVALID_STATION)
                return -EINVAL;

        lockdep_assert_held(&priv->mutex);

        keyconf->hw_key_idx = iwl_get_free_ucode_key_offset(priv);
        if (keyconf->hw_key_idx == WEP_INVALID_OFFSET)
                return -ENOSPC;

        ctx->key_mapping_keys++;

        switch (keyconf->cipher) {
        case WLAN_CIPHER_SUITE_TKIP:
                if (sta)
                        addr = sta->addr;
                else /* station mode case only */
                        addr = ctx->active.bssid_addr;

                /* pre-fill phase 1 key into device cache */
                ieee80211_get_key_rx_seq(keyconf, 0, &seq);
                ieee80211_get_tkip_rx_p1k(keyconf, addr, seq.tkip.iv32, p1k);
                ret = iwlagn_send_sta_key(priv, keyconf, sta_id,
                                          seq.tkip.iv32, p1k, 0);
                break;
        case WLAN_CIPHER_SUITE_CCMP:
        case WLAN_CIPHER_SUITE_WEP40:
        case WLAN_CIPHER_SUITE_WEP104:
                ret = iwlagn_send_sta_key(priv, keyconf, sta_id,
                                          0, NULL, 0);
                break;
        default:
                IWL_ERR(priv, "Unknown cipher %x\n", keyconf->cipher);
                ret = -EINVAL;
        }

        if (ret) {
                ctx->key_mapping_keys--;
                clear_bit(keyconf->hw_key_idx, &priv->ucode_key_table);
        }

        IWL_DEBUG_WEP(priv, "Set dynamic key: cipher=%x len=%d idx=%d sta=%pM ret=%d\n",
                      keyconf->cipher, keyconf->keylen, keyconf->keyidx,
                      sta ? sta->addr : NULL, ret);

        return ret;
}

/**
 * iwlagn_alloc_bcast_station - add broadcast station into driver's station table.
 *
 * This adds the broadcast station into the driver's station table
 * and marks it driver active, so that it will be restored to the
 * device at the next best time.
 */
int iwlagn_alloc_bcast_station(struct iwl_priv *priv,
                               struct iwl_rxon_context *ctx)
{
        struct iwl_link_quality_cmd *link_cmd;
        u8 sta_id;

        spin_lock_bh(&priv->sta_lock);
        sta_id = iwl_prep_station(priv, ctx, iwl_bcast_addr, false, NULL);
        if (sta_id == IWL_INVALID_STATION) {
                IWL_ERR(priv, "Unable to prepare broadcast station\n");
                spin_unlock_bh(&priv->sta_lock);

                return -EINVAL;
        }

        priv->stations[sta_id].used |= IWL_STA_DRIVER_ACTIVE;
        priv->stations[sta_id].used |= IWL_STA_BCAST;
        spin_unlock_bh(&priv->sta_lock);

        link_cmd = iwl_sta_alloc_lq(priv, ctx, sta_id);
        if (!link_cmd) {
                IWL_ERR(priv,
                        "Unable to initialize rate scaling for bcast station.\n");
                return -ENOMEM;
        }

        spin_lock_bh(&priv->sta_lock);
        priv->stations[sta_id].lq = link_cmd;
        spin_unlock_bh(&priv->sta_lock);

        return 0;
}

/**
 * iwl_update_bcast_station - update broadcast station's LQ command
 *
 * Only used by iwlagn. Placed here to have all bcast station management
 * code together.
 */
int iwl_update_bcast_station(struct iwl_priv *priv,
                             struct iwl_rxon_context *ctx)
{
        struct iwl_link_quality_cmd *link_cmd;
        u8 sta_id = ctx->bcast_sta_id;

        link_cmd = iwl_sta_alloc_lq(priv, ctx, sta_id);
        if (!link_cmd) {
                IWL_ERR(priv, "Unable to initialize rate scaling for bcast station.\n");
                return -ENOMEM;
        }

        spin_lock_bh(&priv->sta_lock);
        if (priv->stations[sta_id].lq)
                kfree(priv->stations[sta_id].lq);
        else
                IWL_DEBUG_INFO(priv, "Bcast station rate scaling has not been initialized yet.\n");
        priv->stations[sta_id].lq = link_cmd;
        spin_unlock_bh(&priv->sta_lock);

        return 0;
}

int iwl_update_bcast_stations(struct iwl_priv *priv)
{
        struct iwl_rxon_context *ctx;
        int ret = 0;

        for_each_context(priv, ctx) {
                ret = iwl_update_bcast_station(priv, ctx);
                if (ret)
                        break;
        }

        return ret;
}

/**
 * iwl_sta_tx_modify_enable_tid - Enable Tx for this TID in station table
 */
int iwl_sta_tx_modify_enable_tid(struct iwl_priv *priv, int sta_id, int tid)
{
        struct iwl_addsta_cmd sta_cmd;

        lockdep_assert_held(&priv->mutex);

        /* Remove "disable" flag, to enable Tx for this TID */
        spin_lock_bh(&priv->sta_lock);
        priv->stations[sta_id].sta.sta.modify_mask = STA_MODIFY_TID_DISABLE_TX;
        priv->stations[sta_id].sta.tid_disable_tx &= cpu_to_le16(~(1 << tid));
        priv->stations[sta_id].sta.mode = STA_CONTROL_MODIFY_MSK;
        memcpy(&sta_cmd, &priv->stations[sta_id].sta, sizeof(struct iwl_addsta_cmd));
        spin_unlock_bh(&priv->sta_lock);

        return iwl_send_add_sta(priv, &sta_cmd, 0);
}

int iwl_sta_rx_agg_start(struct iwl_priv *priv, struct ieee80211_sta *sta,
                         int tid, u16 ssn)
{
        int sta_id;
        struct iwl_addsta_cmd sta_cmd;

        lockdep_assert_held(&priv->mutex);

        sta_id = iwl_sta_id(sta);
        if (sta_id == IWL_INVALID_STATION)
                return -ENXIO;

        spin_lock_bh(&priv->sta_lock);
        priv->stations[sta_id].sta.station_flags_msk = 0;
        priv->stations[sta_id].sta.sta.modify_mask = STA_MODIFY_ADDBA_TID_MSK;
        priv->stations[sta_id].sta.add_immediate_ba_tid = (u8)tid;
        priv->stations[sta_id].sta.add_immediate_ba_ssn = cpu_to_le16(ssn);
        priv->stations[sta_id].sta.mode = STA_CONTROL_MODIFY_MSK;
        memcpy(&sta_cmd, &priv->stations[sta_id].sta, sizeof(struct iwl_addsta_cmd));
        spin_unlock_bh(&priv->sta_lock);

        return iwl_send_add_sta(priv, &sta_cmd, 0);
}

int iwl_sta_rx_agg_stop(struct iwl_priv *priv, struct ieee80211_sta *sta,
                        int tid)
{
        int sta_id;
        struct iwl_addsta_cmd sta_cmd;

        lockdep_assert_held(&priv->mutex);

        sta_id = iwl_sta_id(sta);
        if (sta_id == IWL_INVALID_STATION) {
                IWL_ERR(priv, "Invalid station for AGG tid %d\n", tid);
                return -ENXIO;
        }

        spin_lock_bh(&priv->sta_lock);
        priv->stations[sta_id].sta.station_flags_msk = 0;
        priv->stations[sta_id].sta.sta.modify_mask = STA_MODIFY_DELBA_TID_MSK;
        priv->stations[sta_id].sta.remove_immediate_ba_tid = (u8)tid;
        priv->stations[sta_id].sta.mode = STA_CONTROL_MODIFY_MSK;
        memcpy(&sta_cmd, &priv->stations[sta_id].sta, sizeof(struct iwl_addsta_cmd));
        spin_unlock_bh(&priv->sta_lock);

        return iwl_send_add_sta(priv, &sta_cmd, 0);
}



void iwl_sta_modify_sleep_tx_count(struct iwl_priv *priv, int sta_id, int cnt)
{
        struct iwl_addsta_cmd cmd = {
                .mode = STA_CONTROL_MODIFY_MSK,
                .station_flags = STA_FLG_PWR_SAVE_MSK,
                .station_flags_msk = STA_FLG_PWR_SAVE_MSK,
                .sta.sta_id = sta_id,
                .sta.modify_mask = STA_MODIFY_SLEEP_TX_COUNT_MSK,
                .sleep_tx_count = cpu_to_le16(cnt),
        };

        iwl_send_add_sta(priv, &cmd, CMD_ASYNC);
}