/**
 * Copyright (c) 2014 Redpine Signals 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/etherdevice.h>
#include "rsi_debugfs.h"
#include "rsi_mgmt.h"
#include "rsi_common.h"

static const struct ieee80211_channel rsi_2ghz_channels[] = {
        { .band = NL80211_BAND_2GHZ, .center_freq = 2412,
          .hw_value = 1 }, /* Channel 1 */
        { .band = NL80211_BAND_2GHZ, .center_freq = 2417,
          .hw_value = 2 }, /* Channel 2 */
        { .band = NL80211_BAND_2GHZ, .center_freq = 2422,
          .hw_value = 3 }, /* Channel 3 */
        { .band = NL80211_BAND_2GHZ, .center_freq = 2427,
          .hw_value = 4 }, /* Channel 4 */
        { .band = NL80211_BAND_2GHZ, .center_freq = 2432,
          .hw_value = 5 }, /* Channel 5 */
        { .band = NL80211_BAND_2GHZ, .center_freq = 2437,
          .hw_value = 6 }, /* Channel 6 */
        { .band = NL80211_BAND_2GHZ, .center_freq = 2442,
          .hw_value = 7 }, /* Channel 7 */
        { .band = NL80211_BAND_2GHZ, .center_freq = 2447,
          .hw_value = 8 }, /* Channel 8 */
        { .band = NL80211_BAND_2GHZ, .center_freq = 2452,
          .hw_value = 9 }, /* Channel 9 */
        { .band = NL80211_BAND_2GHZ, .center_freq = 2457,
          .hw_value = 10 }, /* Channel 10 */
        { .band = NL80211_BAND_2GHZ, .center_freq = 2462,
          .hw_value = 11 }, /* Channel 11 */
        { .band = NL80211_BAND_2GHZ, .center_freq = 2467,
          .hw_value = 12 }, /* Channel 12 */
        { .band = NL80211_BAND_2GHZ, .center_freq = 2472,
          .hw_value = 13 }, /* Channel 13 */
        { .band = NL80211_BAND_2GHZ, .center_freq = 2484,
          .hw_value = 14 }, /* Channel 14 */
};

static const struct ieee80211_channel rsi_5ghz_channels[] = {
        { .band = NL80211_BAND_5GHZ, .center_freq = 5180,
          .hw_value = 36,  }, /* Channel 36 */
        { .band = NL80211_BAND_5GHZ, .center_freq = 5200,
          .hw_value = 40, }, /* Channel 40 */
        { .band = NL80211_BAND_5GHZ, .center_freq = 5220,
          .hw_value = 44, }, /* Channel 44 */
        { .band = NL80211_BAND_5GHZ, .center_freq = 5240,
          .hw_value = 48, }, /* Channel 48 */
        { .band = NL80211_BAND_5GHZ, .center_freq = 5260,
          .hw_value = 52, }, /* Channel 52 */
        { .band = NL80211_BAND_5GHZ, .center_freq = 5280,
          .hw_value = 56, }, /* Channel 56 */
        { .band = NL80211_BAND_5GHZ, .center_freq = 5300,
          .hw_value = 60, }, /* Channel 60 */
        { .band = NL80211_BAND_5GHZ, .center_freq = 5320,
          .hw_value = 64, }, /* Channel 64 */
        { .band = NL80211_BAND_5GHZ, .center_freq = 5500,
          .hw_value = 100, }, /* Channel 100 */
        { .band = NL80211_BAND_5GHZ, .center_freq = 5520,
          .hw_value = 104, }, /* Channel 104 */
        { .band = NL80211_BAND_5GHZ, .center_freq = 5540,
          .hw_value = 108, }, /* Channel 108 */
        { .band = NL80211_BAND_5GHZ, .center_freq = 5560,
          .hw_value = 112, }, /* Channel 112 */
        { .band = NL80211_BAND_5GHZ, .center_freq = 5580,
          .hw_value = 116, }, /* Channel 116 */
        { .band = NL80211_BAND_5GHZ, .center_freq = 5600,
          .hw_value = 120, }, /* Channel 120 */
        { .band = NL80211_BAND_5GHZ, .center_freq = 5620,
          .hw_value = 124, }, /* Channel 124 */
        { .band = NL80211_BAND_5GHZ, .center_freq = 5640,
          .hw_value = 128, }, /* Channel 128 */
        { .band = NL80211_BAND_5GHZ, .center_freq = 5660,
          .hw_value = 132, }, /* Channel 132 */
        { .band = NL80211_BAND_5GHZ, .center_freq = 5680,
          .hw_value = 136, }, /* Channel 136 */
        { .band = NL80211_BAND_5GHZ, .center_freq = 5700,
          .hw_value = 140, }, /* Channel 140 */
        { .band = NL80211_BAND_5GHZ, .center_freq = 5745,
          .hw_value = 149, }, /* Channel 149 */
        { .band = NL80211_BAND_5GHZ, .center_freq = 5765,
          .hw_value = 153, }, /* Channel 153 */
        { .band = NL80211_BAND_5GHZ, .center_freq = 5785,
          .hw_value = 157, }, /* Channel 157 */
        { .band = NL80211_BAND_5GHZ, .center_freq = 5805,
          .hw_value = 161, }, /* Channel 161 */
        { .band = NL80211_BAND_5GHZ, .center_freq = 5825,
          .hw_value = 165, }, /* Channel 165 */
};

struct ieee80211_rate rsi_rates[12] = {
        { .bitrate = STD_RATE_01  * 5, .hw_value = RSI_RATE_1 },
        { .bitrate = STD_RATE_02  * 5, .hw_value = RSI_RATE_2 },
        { .bitrate = STD_RATE_5_5 * 5, .hw_value = RSI_RATE_5_5 },
        { .bitrate = STD_RATE_11  * 5, .hw_value = RSI_RATE_11 },
        { .bitrate = STD_RATE_06  * 5, .hw_value = RSI_RATE_6 },
        { .bitrate = STD_RATE_09  * 5, .hw_value = RSI_RATE_9 },
        { .bitrate = STD_RATE_12  * 5, .hw_value = RSI_RATE_12 },
        { .bitrate = STD_RATE_18  * 5, .hw_value = RSI_RATE_18 },
        { .bitrate = STD_RATE_24  * 5, .hw_value = RSI_RATE_24 },
        { .bitrate = STD_RATE_36  * 5, .hw_value = RSI_RATE_36 },
        { .bitrate = STD_RATE_48  * 5, .hw_value = RSI_RATE_48 },
        { .bitrate = STD_RATE_54  * 5, .hw_value = RSI_RATE_54 },
};

const u16 rsi_mcsrates[8] = {
        RSI_RATE_MCS0, RSI_RATE_MCS1, RSI_RATE_MCS2, RSI_RATE_MCS3,
        RSI_RATE_MCS4, RSI_RATE_MCS5, RSI_RATE_MCS6, RSI_RATE_MCS7
};

/**
 * rsi_is_cipher_wep() -  This function determines if the cipher is WEP or not.
 * @common: Pointer to the driver private structure.
 *
 * Return: If cipher type is WEP, a value of 1 is returned, else 0.
 */

bool rsi_is_cipher_wep(struct rsi_common *common)
{
        if (((common->secinfo.gtk_cipher == WLAN_CIPHER_SUITE_WEP104) ||
             (common->secinfo.gtk_cipher == WLAN_CIPHER_SUITE_WEP40)) &&
            (!common->secinfo.ptk_cipher))
                return true;
        else
                return false;
}

/**
 * rsi_register_rates_channels() - This function registers channels and rates.
 * @adapter: Pointer to the adapter structure.
 * @band: Operating band to be set.
 *
 * Return: None.
 */
static void rsi_register_rates_channels(struct rsi_hw *adapter, int band)
{
        struct ieee80211_supported_band *sbands = &adapter->sbands[band];
        void *channels = NULL;

        if (band == NL80211_BAND_2GHZ) {
                channels = kmalloc(sizeof(rsi_2ghz_channels), GFP_KERNEL);
                memcpy(channels,
                       rsi_2ghz_channels,
                       sizeof(rsi_2ghz_channels));
                sbands->band = NL80211_BAND_2GHZ;
                sbands->n_channels = ARRAY_SIZE(rsi_2ghz_channels);
                sbands->bitrates = rsi_rates;
                sbands->n_bitrates = ARRAY_SIZE(rsi_rates);
        } else {
                channels = kmalloc(sizeof(rsi_5ghz_channels), GFP_KERNEL);
                memcpy(channels,
                       rsi_5ghz_channels,
                       sizeof(rsi_5ghz_channels));
                sbands->band = NL80211_BAND_5GHZ;
                sbands->n_channels = ARRAY_SIZE(rsi_5ghz_channels);
                sbands->bitrates = &rsi_rates[4];
                sbands->n_bitrates = ARRAY_SIZE(rsi_rates) - 4;
        }

        sbands->channels = channels;

        memset(&sbands->ht_cap, 0, sizeof(struct ieee80211_sta_ht_cap));
        sbands->ht_cap.ht_supported = true;
        sbands->ht_cap.cap = (IEEE80211_HT_CAP_SUP_WIDTH_20_40 |
                              IEEE80211_HT_CAP_SGI_20 |
                              IEEE80211_HT_CAP_SGI_40);
        sbands->ht_cap.ampdu_factor = IEEE80211_HT_MAX_AMPDU_16K;
        sbands->ht_cap.ampdu_density = IEEE80211_HT_MPDU_DENSITY_NONE;
        sbands->ht_cap.mcs.rx_mask[0] = 0xff;
        sbands->ht_cap.mcs.tx_params = IEEE80211_HT_MCS_TX_DEFINED;
        /* sbands->ht_cap.mcs.rx_highest = 0x82; */
}

/**
 * rsi_mac80211_detach() - This function is used to de-initialize the
 *                         Mac80211 stack.
 * @adapter: Pointer to the adapter structure.
 *
 * Return: None.
 */
void rsi_mac80211_detach(struct rsi_hw *adapter)
{
        struct ieee80211_hw *hw = adapter->hw;

        if (hw) {
                ieee80211_stop_queues(hw);
                ieee80211_unregister_hw(hw);
                ieee80211_free_hw(hw);
        }

        rsi_remove_dbgfs(adapter);
}
EXPORT_SYMBOL_GPL(rsi_mac80211_detach);

/**
 * rsi_indicate_tx_status() - This function indicates the transmit status.
 * @adapter: Pointer to the adapter structure.
 * @skb: Pointer to the socket buffer structure.
 * @status: Status
 *
 * Return: None.
 */
void rsi_indicate_tx_status(struct rsi_hw *adapter,
                            struct sk_buff *skb,
                            int status)
{
        struct ieee80211_tx_info *info = IEEE80211_SKB_CB(skb);

        memset(info->driver_data, 0, IEEE80211_TX_INFO_DRIVER_DATA_SIZE);

        if (!status)
                info->flags |= IEEE80211_TX_STAT_ACK;

        ieee80211_tx_status_irqsafe(adapter->hw, skb);
}

/**
 * rsi_mac80211_tx() - This is the handler that 802.11 module calls for each
 *                     transmitted frame.SKB contains the buffer starting
 *                     from the IEEE 802.11 header.
 * @hw: Pointer to the ieee80211_hw structure.
 * @control: Pointer to the ieee80211_tx_control structure
 * @skb: Pointer to the socket buffer structure.
 *
 * Return: None
 */
static void rsi_mac80211_tx(struct ieee80211_hw *hw,
                            struct ieee80211_tx_control *control,
                            struct sk_buff *skb)
{
        struct rsi_hw *adapter = hw->priv;
        struct rsi_common *common = adapter->priv;

        rsi_core_xmit(common, skb);
}

/**
 * rsi_mac80211_start() - This is first handler that 802.11 module calls, since
 *                        the driver init is complete by then, just
 *                        returns success.
 * @hw: Pointer to the ieee80211_hw structure.
 *
 * Return: 0 as success.
 */
static int rsi_mac80211_start(struct ieee80211_hw *hw)
{
        struct rsi_hw *adapter = hw->priv;
        struct rsi_common *common = adapter->priv;

        mutex_lock(&common->mutex);
        common->iface_down = false;
        mutex_unlock(&common->mutex);

        return 0;
}

/**
 * rsi_mac80211_stop() - This is the last handler that 802.11 module calls.
 * @hw: Pointer to the ieee80211_hw structure.
 *
 * Return: None.
 */
static void rsi_mac80211_stop(struct ieee80211_hw *hw)
{
        struct rsi_hw *adapter = hw->priv;
        struct rsi_common *common = adapter->priv;

        mutex_lock(&common->mutex);
        common->iface_down = true;
        mutex_unlock(&common->mutex);
}

/**
 * rsi_mac80211_add_interface() - This function is called when a netdevice
 *                                attached to the hardware is enabled.
 * @hw: Pointer to the ieee80211_hw structure.
 * @vif: Pointer to the ieee80211_vif structure.
 *
 * Return: ret: 0 on success, negative error code on failure.
 */
static int rsi_mac80211_add_interface(struct ieee80211_hw *hw,
                                      struct ieee80211_vif *vif)
{
        struct rsi_hw *adapter = hw->priv;
        struct rsi_common *common = adapter->priv;
        int ret = -EOPNOTSUPP;

        mutex_lock(&common->mutex);
        switch (vif->type) {
        case NL80211_IFTYPE_STATION:
                if (!adapter->sc_nvifs) {
                        ++adapter->sc_nvifs;
                        adapter->vifs[0] = vif;
                        ret = rsi_set_vap_capabilities(common, STA_OPMODE);
                }
                break;
        default:
                rsi_dbg(ERR_ZONE,
                        "%s: Interface type %d not supported\n", __func__,
                        vif->type);
        }
        mutex_unlock(&common->mutex);

        return ret;
}

/**
 * rsi_mac80211_remove_interface() - This function notifies driver that an
 *                                   interface is going down.
 * @hw: Pointer to the ieee80211_hw structure.
 * @vif: Pointer to the ieee80211_vif structure.
 *
 * Return: None.
 */
static void rsi_mac80211_remove_interface(struct ieee80211_hw *hw,
                                          struct ieee80211_vif *vif)
{
        struct rsi_hw *adapter = hw->priv;
        struct rsi_common *common = adapter->priv;

        mutex_lock(&common->mutex);
        if (vif->type == NL80211_IFTYPE_STATION)
                adapter->sc_nvifs--;

        if (!memcmp(adapter->vifs[0], vif, sizeof(struct ieee80211_vif)))
                adapter->vifs[0] = NULL;
        mutex_unlock(&common->mutex);
}

/**
 * rsi_channel_change() - This function is a performs the checks
 *                        required for changing a channel and sets
 *                        the channel accordingly.
 * @hw: Pointer to the ieee80211_hw structure.
 *
 * Return: 0 on success, negative error code on failure.
 */
static int rsi_channel_change(struct ieee80211_hw *hw)
{
        struct rsi_hw *adapter = hw->priv;
        struct rsi_common *common = adapter->priv;
        int status = -EOPNOTSUPP;
        struct ieee80211_channel *curchan = hw->conf.chandef.chan;
        u16 channel = curchan->hw_value;
        struct ieee80211_bss_conf *bss = &adapter->vifs[0]->bss_conf;

        rsi_dbg(INFO_ZONE,
                "%s: Set channel: %d MHz type: %d channel_no %d\n",
                __func__, curchan->center_freq,
                curchan->flags, channel);

        if (bss->assoc) {
                if (!common->hw_data_qs_blocked &&
                    (rsi_get_connected_channel(adapter) != channel)) {
                        rsi_dbg(INFO_ZONE, "blk data q %d\n", channel);
                        if (!rsi_send_block_unblock_frame(common, true))
                                common->hw_data_qs_blocked = true;
                }
        }

        status = rsi_band_check(common);
        if (!status)
                status = rsi_set_channel(adapter->priv, channel);

        if (bss->assoc) {
                if (common->hw_data_qs_blocked &&
                    (rsi_get_connected_channel(adapter) == channel)) {
                        rsi_dbg(INFO_ZONE, "unblk data q %d\n", channel);
                        if (!rsi_send_block_unblock_frame(common, false))
                                common->hw_data_qs_blocked = false;
                }
        } else {
                if (common->hw_data_qs_blocked) {
                        rsi_dbg(INFO_ZONE, "unblk data q %d\n", channel);
                        if (!rsi_send_block_unblock_frame(common, false))
                                common->hw_data_qs_blocked = false;
                }
        }

        return status;
}

/**
 * rsi_mac80211_config() - This function is a handler for configuration
 *                         requests. The stack calls this function to
 *                         change hardware configuration, e.g., channel.
 * @hw: Pointer to the ieee80211_hw structure.
 * @changed: Changed flags set.
 *
 * Return: 0 on success, negative error code on failure.
 */
static int rsi_mac80211_config(struct ieee80211_hw *hw,
                               u32 changed)
{
        struct rsi_hw *adapter = hw->priv;
        struct rsi_common *common = adapter->priv;
        int status = -EOPNOTSUPP;

        mutex_lock(&common->mutex);

        if (changed & IEEE80211_CONF_CHANGE_CHANNEL)
                status = rsi_channel_change(hw);

        mutex_unlock(&common->mutex);

        return status;
}

/**
 * rsi_get_connected_channel() - This function is used to get the current
 *                               connected channel number.
 * @adapter: Pointer to the adapter structure.
 *
 * Return: Current connected AP's channel number is returned.
 */
u16 rsi_get_connected_channel(struct rsi_hw *adapter)
{
        struct ieee80211_vif *vif = adapter->vifs[0];
        if (vif) {
                struct ieee80211_bss_conf *bss = &vif->bss_conf;
                struct ieee80211_channel *channel = bss->chandef.chan;
                return channel->hw_value;
        }

        return 0;
}

/**
 * rsi_mac80211_bss_info_changed() - This function is a handler for config
 *                                   requests related to BSS parameters that
 *                                   may vary during BSS's lifespan.
 * @hw: Pointer to the ieee80211_hw structure.
 * @vif: Pointer to the ieee80211_vif structure.
 * @bss_conf: Pointer to the ieee80211_bss_conf structure.
 * @changed: Changed flags set.
 *
 * Return: None.
 */
static void rsi_mac80211_bss_info_changed(struct ieee80211_hw *hw,
                                          struct ieee80211_vif *vif,
                                          struct ieee80211_bss_conf *bss_conf,
                                          u32 changed)
{
        struct rsi_hw *adapter = hw->priv;
        struct rsi_common *common = adapter->priv;

        mutex_lock(&common->mutex);
        if (changed & BSS_CHANGED_ASSOC) {
                rsi_dbg(INFO_ZONE, "%s: Changed Association status: %d\n",
                        __func__, bss_conf->assoc);
                rsi_inform_bss_status(common,
                                      bss_conf->assoc,
                                      bss_conf->bssid,
                                      bss_conf->qos,
                                      bss_conf->aid);
        }

        if (changed & BSS_CHANGED_CQM) {
                common->cqm_info.last_cqm_event_rssi = 0;
                common->cqm_info.rssi_thold = bss_conf->cqm_rssi_thold;
                common->cqm_info.rssi_hyst = bss_conf->cqm_rssi_hyst;
                rsi_dbg(INFO_ZONE, "RSSI throld & hysteresis are: %d %d\n",
                        common->cqm_info.rssi_thold,
                        common->cqm_info.rssi_hyst);
        }
        mutex_unlock(&common->mutex);
}

/**
 * rsi_mac80211_conf_filter() - This function configure the device's RX filter.
 * @hw: Pointer to the ieee80211_hw structure.
 * @changed: Changed flags set.
 * @total_flags: Total initial flags set.
 * @multicast: Multicast.
 *
 * Return: None.
 */
static void rsi_mac80211_conf_filter(struct ieee80211_hw *hw,
                                     u32 changed_flags,
                                     u32 *total_flags,
                                     u64 multicast)
{
        /* Not doing much here as of now */
        *total_flags &= RSI_SUPP_FILTERS;
}

/**
 * rsi_mac80211_conf_tx() - This function configures TX queue parameters
 *                          (EDCF (aifs, cw_min, cw_max), bursting)
 *                          for a hardware TX queue.
 * @hw: Pointer to the ieee80211_hw structure
 * @vif: Pointer to the ieee80211_vif structure.
 * @queue: Queue number.
 * @params: Pointer to ieee80211_tx_queue_params structure.
 *
 * Return: 0 on success, negative error code on failure.
 */
static int rsi_mac80211_conf_tx(struct ieee80211_hw *hw,
                                struct ieee80211_vif *vif, u16 queue,
                                const struct ieee80211_tx_queue_params *params)
{
        struct rsi_hw *adapter = hw->priv;
        struct rsi_common *common = adapter->priv;
        u8 idx = 0;

        if (queue >= IEEE80211_NUM_ACS)
                return 0;

        rsi_dbg(INFO_ZONE,
                "%s: Conf queue %d, aifs: %d, cwmin: %d cwmax: %d, txop: %d\n",
                __func__, queue, params->aifs,
                params->cw_min, params->cw_max, params->txop);

        mutex_lock(&common->mutex);
        /* Map into the way the f/w expects */
        switch (queue) {
        case IEEE80211_AC_VO:
                idx = VO_Q;
                break;
        case IEEE80211_AC_VI:
                idx = VI_Q;
                break;
        case IEEE80211_AC_BE:
                idx = BE_Q;
                break;
        case IEEE80211_AC_BK:
                idx = BK_Q;
                break;
        default:
                idx = BE_Q;
                break;
        }

        memcpy(&common->edca_params[idx],
               params,
               sizeof(struct ieee80211_tx_queue_params));
        mutex_unlock(&common->mutex);

        return 0;
}

/**
 * rsi_hal_key_config() - This function loads the keys into the firmware.
 * @hw: Pointer to the ieee80211_hw structure.
 * @vif: Pointer to the ieee80211_vif structure.
 * @key: Pointer to the ieee80211_key_conf structure.
 *
 * Return: status: 0 on success, -1 on failure.
 */
static int rsi_hal_key_config(struct ieee80211_hw *hw,
                              struct ieee80211_vif *vif,
                              struct ieee80211_key_conf *key)
{
        struct rsi_hw *adapter = hw->priv;
        int status;
        u8 key_type;

        if (key->flags & IEEE80211_KEY_FLAG_PAIRWISE)
                key_type = RSI_PAIRWISE_KEY;
        else
                key_type = RSI_GROUP_KEY;

        rsi_dbg(ERR_ZONE, "%s: Cipher 0x%x key_type: %d key_len: %d\n",
                __func__, key->cipher, key_type, key->keylen);

        if ((key->cipher == WLAN_CIPHER_SUITE_WEP104) ||
            (key->cipher == WLAN_CIPHER_SUITE_WEP40)) {
                status = rsi_hal_load_key(adapter->priv,
                                          key->key,
                                          key->keylen,
                                          RSI_PAIRWISE_KEY,
                                          key->keyidx,
                                          key->cipher);
                if (status)
                        return status;
        }
        return rsi_hal_load_key(adapter->priv,
                                key->key,
                                key->keylen,
                                key_type,
                                key->keyidx,
                                key->cipher);
}

/**
 * rsi_mac80211_set_key() - This function sets type of key to be loaded.
 * @hw: Pointer to the ieee80211_hw structure.
 * @cmd: enum set_key_cmd.
 * @vif: Pointer to the ieee80211_vif structure.
 * @sta: Pointer to the ieee80211_sta structure.
 * @key: Pointer to the ieee80211_key_conf structure.
 *
 * Return: status: 0 on success, negative error code on failure.
 */
static int rsi_mac80211_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 rsi_hw *adapter = hw->priv;
        struct rsi_common *common = adapter->priv;
        struct security_info *secinfo = &common->secinfo;
        int status;

        mutex_lock(&common->mutex);
        switch (cmd) {
        case SET_KEY:
                secinfo->security_enable = true;
                status = rsi_hal_key_config(hw, vif, key);
                if (status) {
                        mutex_unlock(&common->mutex);
                        return status;
                }

                if (key->flags & IEEE80211_KEY_FLAG_PAIRWISE)
                        secinfo->ptk_cipher = key->cipher;
                else
                        secinfo->gtk_cipher = key->cipher;

                key->hw_key_idx = key->keyidx;
                key->flags |= IEEE80211_KEY_FLAG_GENERATE_IV;

                rsi_dbg(ERR_ZONE, "%s: RSI set_key\n", __func__);
                break;

        case DISABLE_KEY:
                secinfo->security_enable = false;
                rsi_dbg(ERR_ZONE, "%s: RSI del key\n", __func__);
                memset(key, 0, sizeof(struct ieee80211_key_conf));
                status = rsi_hal_key_config(hw, vif, key);
                break;

        default:
                status = -EOPNOTSUPP;
                break;
        }

        mutex_unlock(&common->mutex);
        return status;
}

/**
 * rsi_mac80211_ampdu_action() - This function selects the AMPDU action for
 *                               the corresponding mlme_action flag and
 *                               informs the f/w regarding this.
 * @hw: Pointer to the ieee80211_hw structure.
 * @vif: Pointer to the ieee80211_vif structure.
 * @params: Pointer to A-MPDU action parameters
 *
 * Return: status: 0 on success, negative error code on failure.
 */
static int rsi_mac80211_ampdu_action(struct ieee80211_hw *hw,
                                     struct ieee80211_vif *vif,
                                     struct ieee80211_ampdu_params *params)
{
        int status = -EOPNOTSUPP;
        struct rsi_hw *adapter = hw->priv;
        struct rsi_common *common = adapter->priv;
        u16 seq_no = 0;
        u8 ii = 0;
        struct ieee80211_sta *sta = params->sta;
        enum ieee80211_ampdu_mlme_action action = params->action;
        u16 tid = params->tid;
        u16 *ssn = &params->ssn;
        u8 buf_size = params->buf_size;

        for (ii = 0; ii < RSI_MAX_VIFS; ii++) {
                if (vif == adapter->vifs[ii])
                        break;
        }

        mutex_lock(&common->mutex);
        rsi_dbg(INFO_ZONE, "%s: AMPDU action %d called\n", __func__, action);
        if (ssn != NULL)
                seq_no = *ssn;

        switch (action) {
        case IEEE80211_AMPDU_RX_START:
                status = rsi_send_aggregation_params_frame(common,
                                                           tid,
                                                           seq_no,
                                                           buf_size,
                                                           STA_RX_ADDBA_DONE);
                break;

        case IEEE80211_AMPDU_RX_STOP:
                status = rsi_send_aggregation_params_frame(common,
                                                           tid,
                                                           0,
                                                           buf_size,
                                                           STA_RX_DELBA);
                break;

        case IEEE80211_AMPDU_TX_START:
                common->vif_info[ii].seq_start = seq_no;
                ieee80211_start_tx_ba_cb_irqsafe(vif, sta->addr, tid);
                status = 0;
                break;

        case IEEE80211_AMPDU_TX_STOP_CONT:
        case IEEE80211_AMPDU_TX_STOP_FLUSH:
        case IEEE80211_AMPDU_TX_STOP_FLUSH_CONT:
                status = rsi_send_aggregation_params_frame(common,
                                                           tid,
                                                           seq_no,
                                                           buf_size,
                                                           STA_TX_DELBA);
                if (!status)
                        ieee80211_stop_tx_ba_cb_irqsafe(vif, sta->addr, tid);
                break;

        case IEEE80211_AMPDU_TX_OPERATIONAL:
                status = rsi_send_aggregation_params_frame(common,
                                                           tid,
                                                           common->vif_info[ii]
                                                                .seq_start,
                                                           buf_size,
                                                           STA_TX_ADDBA_DONE);
                break;

        default:
                rsi_dbg(ERR_ZONE, "%s: Uknown AMPDU action\n", __func__);
                break;
        }

        mutex_unlock(&common->mutex);
        return status;
}

/**
 * rsi_mac80211_set_rts_threshold() - This function sets rts threshold value.
 * @hw: Pointer to the ieee80211_hw structure.
 * @value: Rts threshold value.
 *
 * Return: 0 on success.
 */
static int rsi_mac80211_set_rts_threshold(struct ieee80211_hw *hw,
                                          u32 value)
{
        struct rsi_hw *adapter = hw->priv;
        struct rsi_common *common = adapter->priv;

        mutex_lock(&common->mutex);
        common->rts_threshold = value;
        mutex_unlock(&common->mutex);

        return 0;
}

/**
 * rsi_mac80211_set_rate_mask() - This function sets bitrate_mask to be used.
 * @hw: Pointer to the ieee80211_hw structure
 * @vif: Pointer to the ieee80211_vif structure.
 * @mask: Pointer to the cfg80211_bitrate_mask structure.
 *
 * Return: 0 on success.
 */
static int rsi_mac80211_set_rate_mask(struct ieee80211_hw *hw,
                                      struct ieee80211_vif *vif,
                                      const struct cfg80211_bitrate_mask *mask)
{
        struct rsi_hw *adapter = hw->priv;
        struct rsi_common *common = adapter->priv;
        enum nl80211_band band = hw->conf.chandef.chan->band;

        mutex_lock(&common->mutex);
        common->fixedrate_mask[band] = 0;

        if (mask->control[band].legacy == 0xfff) {
                common->fixedrate_mask[band] =
                        (mask->control[band].ht_mcs[0] << 12);
        } else {
                common->fixedrate_mask[band] =
                        mask->control[band].legacy;
        }
        mutex_unlock(&common->mutex);

        return 0;
}

/**
 * rsi_perform_cqm() - This function performs cqm.
 * @common: Pointer to the driver private structure.
 * @bssid: pointer to the bssid.
 * @rssi: RSSI value.
 */
static void rsi_perform_cqm(struct rsi_common *common,
                            u8 *bssid,
                            s8 rssi)
{
        struct rsi_hw *adapter = common->priv;
        s8 last_event = common->cqm_info.last_cqm_event_rssi;
        int thold = common->cqm_info.rssi_thold;
        u32 hyst = common->cqm_info.rssi_hyst;
        enum nl80211_cqm_rssi_threshold_event event;

        if (rssi < thold && (last_event == 0 || rssi < (last_event - hyst)))
                event = NL80211_CQM_RSSI_THRESHOLD_EVENT_LOW;
        else if (rssi > thold &&
                 (last_event == 0 || rssi > (last_event + hyst)))
                event = NL80211_CQM_RSSI_THRESHOLD_EVENT_HIGH;
        else
                return;

        common->cqm_info.last_cqm_event_rssi = rssi;
        rsi_dbg(INFO_ZONE, "CQM: Notifying event: %d\n", event);
        ieee80211_cqm_rssi_notify(adapter->vifs[0], event, GFP_KERNEL);

        return;
}

/**
 * rsi_fill_rx_status() - This function fills rx status in
 *                        ieee80211_rx_status structure.
 * @hw: Pointer to the ieee80211_hw structure.
 * @skb: Pointer to the socket buffer structure.
 * @common: Pointer to the driver private structure.
 * @rxs: Pointer to the ieee80211_rx_status structure.
 *
 * Return: None.
 */
static void rsi_fill_rx_status(struct ieee80211_hw *hw,
                               struct sk_buff *skb,
                               struct rsi_common *common,
                               struct ieee80211_rx_status *rxs)
{
        struct ieee80211_bss_conf *bss = &common->priv->vifs[0]->bss_conf;
        struct ieee80211_tx_info *info = IEEE80211_SKB_CB(skb);
        struct skb_info *rx_params = (struct skb_info *)info->driver_data;
        struct ieee80211_hdr *hdr;
        char rssi = rx_params->rssi;
        u8 hdrlen = 0;
        u8 channel = rx_params->channel;
        s32 freq;

        hdr = ((struct ieee80211_hdr *)(skb->data));
        hdrlen = ieee80211_hdrlen(hdr->frame_control);

        memset(info, 0, sizeof(struct ieee80211_tx_info));

        rxs->signal = -(rssi);

        rxs->band = common->band;

        freq = ieee80211_channel_to_frequency(channel, rxs->band);

        if (freq)
                rxs->freq = freq;

        if (ieee80211_has_protected(hdr->frame_control)) {
                if (rsi_is_cipher_wep(common)) {
                        memmove(skb->data + 4, skb->data, hdrlen);
                        skb_pull(skb, 4);
                } else {
                        memmove(skb->data + 8, skb->data, hdrlen);
                        skb_pull(skb, 8);
                        rxs->flag |= RX_FLAG_MMIC_STRIPPED;
                }
                rxs->flag |= RX_FLAG_DECRYPTED;
                rxs->flag |= RX_FLAG_IV_STRIPPED;
        }

        /* CQM only for connected AP beacons, the RSSI is a weighted avg */
        if (bss->assoc && !(memcmp(bss->bssid, hdr->addr2, ETH_ALEN))) {
                if (ieee80211_is_beacon(hdr->frame_control))
                        rsi_perform_cqm(common, hdr->addr2, rxs->signal);
        }

        return;
}

/**
 * rsi_indicate_pkt_to_os() - This function sends recieved packet to mac80211.
 * @common: Pointer to the driver private structure.
 * @skb: Pointer to the socket buffer structure.
 *
 * Return: None.
 */
void rsi_indicate_pkt_to_os(struct rsi_common *common,
                            struct sk_buff *skb)
{
        struct rsi_hw *adapter = common->priv;
        struct ieee80211_hw *hw = adapter->hw;
        struct ieee80211_rx_status *rx_status = IEEE80211_SKB_RXCB(skb);

        if ((common->iface_down) || (!adapter->sc_nvifs)) {
                dev_kfree_skb(skb);
                return;
        }

        /* filling in the ieee80211_rx_status flags */
        rsi_fill_rx_status(hw, skb, common, rx_status);

        ieee80211_rx_irqsafe(hw, skb);
}

static void rsi_set_min_rate(struct ieee80211_hw *hw,
                             struct ieee80211_sta *sta,
                             struct rsi_common *common)
{
        u8 band = hw->conf.chandef.chan->band;
        u8 ii;
        u32 rate_bitmap;
        bool matched = false;

        common->bitrate_mask[band] = sta->supp_rates[band];

        rate_bitmap = (common->fixedrate_mask[band] & sta->supp_rates[band]);

        if (rate_bitmap & 0xfff) {
                /* Find out the min rate */
                for (ii = 0; ii < ARRAY_SIZE(rsi_rates); ii++) {
                        if (rate_bitmap & BIT(ii)) {
                                common->min_rate = rsi_rates[ii].hw_value;
                                matched = true;
                                break;
                        }
                }
        }

        common->vif_info[0].is_ht = sta->ht_cap.ht_supported;

        if ((common->vif_info[0].is_ht) && (rate_bitmap >> 12)) {
                for (ii = 0; ii < ARRAY_SIZE(rsi_mcsrates); ii++) {
                        if ((rate_bitmap >> 12) & BIT(ii)) {
                                common->min_rate = rsi_mcsrates[ii];
                                matched = true;
                                break;
                        }
                }
        }

        if (!matched)
                common->min_rate = 0xffff;
}

/**
 * rsi_mac80211_sta_add() - This function notifies driver about a peer getting
 *                          connected.
 * @hw: pointer to the ieee80211_hw structure.
 * @vif: Pointer to the ieee80211_vif structure.
 * @sta: Pointer to the ieee80211_sta structure.
 *
 * Return: 0 on success, -1 on failure.
 */
static int rsi_mac80211_sta_add(struct ieee80211_hw *hw,
                                struct ieee80211_vif *vif,
                                struct ieee80211_sta *sta)
{
        struct rsi_hw *adapter = hw->priv;
        struct rsi_common *common = adapter->priv;

        mutex_lock(&common->mutex);

        rsi_set_min_rate(hw, sta, common);

        if ((sta->ht_cap.cap & IEEE80211_HT_CAP_SGI_20) ||
            (sta->ht_cap.cap & IEEE80211_HT_CAP_SGI_40)) {
                common->vif_info[0].sgi = true;
        }

        if (sta->ht_cap.ht_supported)
                ieee80211_start_tx_ba_session(sta, 0, 0);

        mutex_unlock(&common->mutex);

        return 0;
}

/**
 * rsi_mac80211_sta_remove() - This function notifies driver about a peer
 *                             getting disconnected.
 * @hw: Pointer to the ieee80211_hw structure.
 * @vif: Pointer to the ieee80211_vif structure.
 * @sta: Pointer to the ieee80211_sta structure.
 *
 * Return: 0 on success, -1 on failure.
 */
static int rsi_mac80211_sta_remove(struct ieee80211_hw *hw,
                                   struct ieee80211_vif *vif,
                                   struct ieee80211_sta *sta)
{
        struct rsi_hw *adapter = hw->priv;
        struct rsi_common *common = adapter->priv;

        mutex_lock(&common->mutex);

        /* Resetting all the fields to default values */
        common->bitrate_mask[NL80211_BAND_2GHZ] = 0;
        common->bitrate_mask[NL80211_BAND_5GHZ] = 0;
        common->min_rate = 0xffff;
        common->vif_info[0].is_ht = false;
        common->vif_info[0].sgi = false;
        common->vif_info[0].seq_start = 0;
        common->secinfo.ptk_cipher = 0;
        common->secinfo.gtk_cipher = 0;
        mutex_unlock(&common->mutex);

        return 0;
}

static struct ieee80211_ops mac80211_ops = {
        .tx = rsi_mac80211_tx,
        .start = rsi_mac80211_start,
        .stop = rsi_mac80211_stop,
        .add_interface = rsi_mac80211_add_interface,
        .remove_interface = rsi_mac80211_remove_interface,
        .config = rsi_mac80211_config,
        .bss_info_changed = rsi_mac80211_bss_info_changed,
        .conf_tx = rsi_mac80211_conf_tx,
        .configure_filter = rsi_mac80211_conf_filter,
        .set_key = rsi_mac80211_set_key,
        .set_rts_threshold = rsi_mac80211_set_rts_threshold,
        .set_bitrate_mask = rsi_mac80211_set_rate_mask,
        .ampdu_action = rsi_mac80211_ampdu_action,
        .sta_add = rsi_mac80211_sta_add,
        .sta_remove = rsi_mac80211_sta_remove,
};

/**
 * rsi_mac80211_attach() - This function is used to initialize Mac80211 stack.
 * @common: Pointer to the driver private structure.
 *
 * Return: 0 on success, -1 on failure.
 */
int rsi_mac80211_attach(struct rsi_common *common)
{
        int status = 0;
        struct ieee80211_hw *hw = NULL;
        struct wiphy *wiphy = NULL;
        struct rsi_hw *adapter = common->priv;
        u8 addr_mask[ETH_ALEN] = {0x0, 0x0, 0x0, 0x0, 0x0, 0x3};

        rsi_dbg(INIT_ZONE, "%s: Performing mac80211 attach\n", __func__);

        hw = ieee80211_alloc_hw(sizeof(struct rsi_hw), &mac80211_ops);
        if (!hw) {
                rsi_dbg(ERR_ZONE, "%s: ieee80211 hw alloc failed\n", __func__);
                return -ENOMEM;
        }

        wiphy = hw->wiphy;

        SET_IEEE80211_DEV(hw, adapter->device);

        hw->priv = adapter;
        adapter->hw = hw;

        ieee80211_hw_set(hw, SIGNAL_DBM);
        ieee80211_hw_set(hw, HAS_RATE_CONTROL);
        ieee80211_hw_set(hw, AMPDU_AGGREGATION);

        hw->queues = MAX_HW_QUEUES;
        hw->extra_tx_headroom = RSI_NEEDED_HEADROOM;

        hw->max_rates = 1;
        hw->max_rate_tries = MAX_RETRIES;

        hw->max_tx_aggregation_subframes = 6;
        rsi_register_rates_channels(adapter, NL80211_BAND_2GHZ);
        rsi_register_rates_channels(adapter, NL80211_BAND_5GHZ);
        hw->rate_control_algorithm = "AARF";

        SET_IEEE80211_PERM_ADDR(hw, common->mac_addr);
        ether_addr_copy(hw->wiphy->addr_mask, addr_mask);

        wiphy->interface_modes = BIT(NL80211_IFTYPE_STATION);
        wiphy->signal_type = CFG80211_SIGNAL_TYPE_MBM;
        wiphy->retry_short = RETRY_SHORT;
        wiphy->retry_long  = RETRY_LONG;
        wiphy->frag_threshold = IEEE80211_MAX_FRAG_THRESHOLD;
        wiphy->rts_threshold = IEEE80211_MAX_RTS_THRESHOLD;
        wiphy->flags = 0;

        wiphy->available_antennas_rx = 1;
        wiphy->available_antennas_tx = 1;
        wiphy->bands[NL80211_BAND_2GHZ] =
                &adapter->sbands[NL80211_BAND_2GHZ];
        wiphy->bands[NL80211_BAND_5GHZ] =
                &adapter->sbands[NL80211_BAND_5GHZ];

        status = ieee80211_register_hw(hw);
        if (status)
                return status;

        return rsi_init_dbgfs(adapter);
}