/******************************************************************************
 *
 * 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.
 *
 * This program is free software; you can redistribute it and/or modify it
 * under the terms of version 2 of the GNU General Public License as
 * published by the Free Software Foundation.
 *
 * This program is distributed in the hope that it will be useful, but WITHOUT
 * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
 * FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License for
 * more details.
 *
 * You should have received a copy of the GNU General Public License along with
 * this program; if not, write to the Free Software Foundation, Inc.,
 * 51 Franklin Street, Fifth Floor, Boston, MA 02110, USA
 *
 * The full GNU General Public License is included in this distribution in the
 * file called LICENSE.
 *
 * Contact Information:
 *  Intel Linux Wireless <linuxwifi@intel.com>
 * Intel Corporation, 5200 N.E. Elam Young Parkway, Hillsboro, OR 97124-6497
 *
 *****************************************************************************/
#include <linux/kernel.h>
#include <linux/module.h>
#include <linux/slab.h>
#include <linux/dma-mapping.h>
#include <linux/delay.h>
#include <linux/sched.h>
#include <linux/skbuff.h>
#include <linux/netdevice.h>
#include <linux/etherdevice.h>
#include <linux/if_arp.h>

#include <net/ieee80211_radiotap.h>
#include <net/mac80211.h>

#include <asm/div64.h>

#include "iwl-io.h"
#include "iwl-trans.h"
#include "iwl-op-mode.h"
#include "iwl-modparams.h"

#include "dev.h"
#include "calib.h"
#include "agn.h"

/*****************************************************************************
 *
 * mac80211 entry point functions
 *
 *****************************************************************************/

static const struct ieee80211_iface_limit iwlagn_sta_ap_limits[] = {
        {
                .max = 1,
                .types = BIT(NL80211_IFTYPE_STATION),
        },
        {
                .max = 1,
                .types = BIT(NL80211_IFTYPE_AP),
        },
};

static const struct ieee80211_iface_limit iwlagn_2sta_limits[] = {
        {
                .max = 2,
                .types = BIT(NL80211_IFTYPE_STATION),
        },
};

static const struct ieee80211_iface_combination
iwlagn_iface_combinations_dualmode[] = {
        { .num_different_channels = 1,
          .max_interfaces = 2,
          .beacon_int_infra_match = true,
          .limits = iwlagn_sta_ap_limits,
          .n_limits = ARRAY_SIZE(iwlagn_sta_ap_limits),
        },
        { .num_different_channels = 1,
          .max_interfaces = 2,
          .limits = iwlagn_2sta_limits,
          .n_limits = ARRAY_SIZE(iwlagn_2sta_limits),
        },
};

/*
 * Not a mac80211 entry point function, but it fits in with all the
 * other mac80211 functions grouped here.
 */
int iwlagn_mac_setup_register(struct iwl_priv *priv,
                              const struct iwl_ucode_capabilities *capa)
{
        int ret;
        struct ieee80211_hw *hw = priv->hw;
        struct iwl_rxon_context *ctx;

        hw->rate_control_algorithm = "iwl-agn-rs";

        /* Tell mac80211 our characteristics */
        ieee80211_hw_set(hw, SIGNAL_DBM);
        ieee80211_hw_set(hw, AMPDU_AGGREGATION);
        ieee80211_hw_set(hw, NEED_DTIM_BEFORE_ASSOC);
        ieee80211_hw_set(hw, SPECTRUM_MGMT);
        ieee80211_hw_set(hw, REPORTS_TX_ACK_STATUS);
        ieee80211_hw_set(hw, QUEUE_CONTROL);
        ieee80211_hw_set(hw, SUPPORTS_PS);
        ieee80211_hw_set(hw, SUPPORTS_DYNAMIC_PS);
        ieee80211_hw_set(hw, SUPPORT_FAST_XMIT);
        ieee80211_hw_set(hw, WANT_MONITOR_VIF);

        if (priv->trans->max_skb_frags)
                hw->netdev_features = NETIF_F_HIGHDMA | NETIF_F_SG;

        hw->offchannel_tx_hw_queue = IWL_AUX_QUEUE;
        hw->radiotap_mcs_details |= IEEE80211_RADIOTAP_MCS_HAVE_FMT;

        /*
         * Including the following line will crash some AP's.  This
         * workaround removes the stimulus which causes the crash until
         * the AP software can be fixed.
        hw->max_tx_aggregation_subframes = LINK_QUAL_AGG_FRAME_LIMIT_DEF;
         */

        if (priv->nvm_data->sku_cap_11n_enable)
                hw->wiphy->features |= NL80211_FEATURE_DYNAMIC_SMPS |
                                       NL80211_FEATURE_STATIC_SMPS;

        /*
         * Enable 11w if advertised by firmware and software crypto
         * is not enabled (as the firmware will interpret some mgmt
         * packets, so enabling it with software crypto isn't safe)
         */
        if (priv->fw->ucode_capa.flags & IWL_UCODE_TLV_FLAGS_MFP &&
            !iwlwifi_mod_params.sw_crypto)
                ieee80211_hw_set(hw, MFP_CAPABLE);

        hw->sta_data_size = sizeof(struct iwl_station_priv);
        hw->vif_data_size = sizeof(struct iwl_vif_priv);

        for_each_context(priv, ctx) {
                hw->wiphy->interface_modes |= ctx->interface_modes;
                hw->wiphy->interface_modes |= ctx->exclusive_interface_modes;
        }

        BUILD_BUG_ON(NUM_IWL_RXON_CTX != 2);

        if (hw->wiphy->interface_modes & BIT(NL80211_IFTYPE_AP)) {
                hw->wiphy->iface_combinations =
                        iwlagn_iface_combinations_dualmode;
                hw->wiphy->n_iface_combinations =
                        ARRAY_SIZE(iwlagn_iface_combinations_dualmode);
        }

        hw->wiphy->flags |= WIPHY_FLAG_IBSS_RSN;
        hw->wiphy->regulatory_flags |= REGULATORY_CUSTOM_REG |
                                       REGULATORY_DISABLE_BEACON_HINTS;

#ifdef CONFIG_PM_SLEEP
        if (priv->fw->img[IWL_UCODE_WOWLAN].num_sec &&
            priv->trans->ops->d3_suspend &&
            priv->trans->ops->d3_resume &&
            device_can_wakeup(priv->trans->dev)) {
                priv->wowlan_support.flags = WIPHY_WOWLAN_MAGIC_PKT |
                                             WIPHY_WOWLAN_DISCONNECT |
                                             WIPHY_WOWLAN_EAP_IDENTITY_REQ |
                                             WIPHY_WOWLAN_RFKILL_RELEASE;
                if (!iwlwifi_mod_params.sw_crypto)
                        priv->wowlan_support.flags |=
                                WIPHY_WOWLAN_SUPPORTS_GTK_REKEY |
                                WIPHY_WOWLAN_GTK_REKEY_FAILURE;

                priv->wowlan_support.n_patterns = IWLAGN_WOWLAN_MAX_PATTERNS;
                priv->wowlan_support.pattern_min_len =
                                        IWLAGN_WOWLAN_MIN_PATTERN_LEN;
                priv->wowlan_support.pattern_max_len =
                                        IWLAGN_WOWLAN_MAX_PATTERN_LEN;
                hw->wiphy->wowlan = &priv->wowlan_support;
        }
#endif

        if (iwlwifi_mod_params.power_save)
                hw->wiphy->flags |= WIPHY_FLAG_PS_ON_BY_DEFAULT;
        else
                hw->wiphy->flags &= ~WIPHY_FLAG_PS_ON_BY_DEFAULT;

        hw->wiphy->max_scan_ssids = PROBE_OPTION_MAX;
        /* we create the 802.11 header and a max-length SSID element */
        hw->wiphy->max_scan_ie_len = capa->max_probe_length - 24 - 34;

        /*
         * We don't use all queues: 4 and 9 are unused and any
         * aggregation queue gets mapped down to the AC queue.
         */
        hw->queues = IWLAGN_FIRST_AMPDU_QUEUE;

        hw->max_listen_interval = IWL_CONN_MAX_LISTEN_INTERVAL;

        if (priv->nvm_data->bands[NL80211_BAND_2GHZ].n_channels)
                priv->hw->wiphy->bands[NL80211_BAND_2GHZ] =
                        &priv->nvm_data->bands[NL80211_BAND_2GHZ];
        if (priv->nvm_data->bands[NL80211_BAND_5GHZ].n_channels)
                priv->hw->wiphy->bands[NL80211_BAND_5GHZ] =
                        &priv->nvm_data->bands[NL80211_BAND_5GHZ];

        hw->wiphy->hw_version = priv->trans->hw_id;

        iwl_leds_init(priv);

        ret = ieee80211_register_hw(priv->hw);
        if (ret) {
                IWL_ERR(priv, "Failed to register hw (error %d)\n", ret);
                iwl_leds_exit(priv);
                return ret;
        }
        priv->mac80211_registered = 1;

        return 0;
}

void iwlagn_mac_unregister(struct iwl_priv *priv)
{
        if (!priv->mac80211_registered)
                return;
        iwl_leds_exit(priv);
        ieee80211_unregister_hw(priv->hw);
        priv->mac80211_registered = 0;
}

static int __iwl_up(struct iwl_priv *priv)
{
        struct iwl_rxon_context *ctx;
        int ret;

        lockdep_assert_held(&priv->mutex);

        if (test_bit(STATUS_EXIT_PENDING, &priv->status)) {
                IWL_WARN(priv, "Exit pending; will not bring the NIC up\n");
                return -EIO;
        }

        for_each_context(priv, ctx) {
                ret = iwlagn_alloc_bcast_station(priv, ctx);
                if (ret) {
                        iwl_dealloc_bcast_stations(priv);
                        return ret;
                }
        }

        ret = iwl_trans_start_hw(priv->trans);
        if (ret) {
                IWL_ERR(priv, "Failed to start HW: %d\n", ret);
                goto error;
        }

        ret = iwl_run_init_ucode(priv);
        if (ret) {
                IWL_ERR(priv, "Failed to run INIT ucode: %d\n", ret);
                goto error;
        }

        ret = iwl_trans_start_hw(priv->trans);
        if (ret) {
                IWL_ERR(priv, "Failed to start HW: %d\n", ret);
                goto error;
        }

        ret = iwl_load_ucode_wait_alive(priv, IWL_UCODE_REGULAR);
        if (ret) {
                IWL_ERR(priv, "Failed to start RT ucode: %d\n", ret);
                goto error;
        }

        ret = iwl_alive_start(priv);
        if (ret)
                goto error;
        return 0;

 error:
        set_bit(STATUS_EXIT_PENDING, &priv->status);
        iwl_down(priv);
        clear_bit(STATUS_EXIT_PENDING, &priv->status);

        IWL_ERR(priv, "Unable to initialize device.\n");
        return ret;
}

static int iwlagn_mac_start(struct ieee80211_hw *hw)
{
        struct iwl_priv *priv = IWL_MAC80211_GET_DVM(hw);
        int ret;

        IWL_DEBUG_MAC80211(priv, "enter\n");

        /* we should be verifying the device is ready to be opened */
        mutex_lock(&priv->mutex);
        ret = __iwl_up(priv);
        mutex_unlock(&priv->mutex);
        if (ret)
                return ret;

        IWL_DEBUG_INFO(priv, "Start UP work done.\n");

        /* Now we should be done, and the READY bit should be set. */
        if (WARN_ON(!test_bit(STATUS_READY, &priv->status)))
                ret = -EIO;

        iwlagn_led_enable(priv);

        priv->is_open = 1;
        IWL_DEBUG_MAC80211(priv, "leave\n");
        return 0;
}

static void iwlagn_mac_stop(struct ieee80211_hw *hw)
{
        struct iwl_priv *priv = IWL_MAC80211_GET_DVM(hw);

        IWL_DEBUG_MAC80211(priv, "enter\n");

        if (!priv->is_open)
                return;

        priv->is_open = 0;

        mutex_lock(&priv->mutex);
        iwl_down(priv);
        mutex_unlock(&priv->mutex);

        iwl_cancel_deferred_work(priv);

        flush_workqueue(priv->workqueue);

        IWL_DEBUG_MAC80211(priv, "leave\n");
}

static void iwlagn_mac_set_rekey_data(struct ieee80211_hw *hw,
                                      struct ieee80211_vif *vif,
                                      struct cfg80211_gtk_rekey_data *data)
{
        struct iwl_priv *priv = IWL_MAC80211_GET_DVM(hw);

        if (iwlwifi_mod_params.sw_crypto)
                return;

        IWL_DEBUG_MAC80211(priv, "enter\n");
        mutex_lock(&priv->mutex);

        if (priv->contexts[IWL_RXON_CTX_BSS].vif != vif)
                goto out;

        memcpy(priv->kek, data->kek, NL80211_KEK_LEN);
        memcpy(priv->kck, data->kck, NL80211_KCK_LEN);
        priv->replay_ctr =
                cpu_to_le64(be64_to_cpup((__be64 *)&data->replay_ctr));
        priv->have_rekey_data = true;

 out:
        mutex_unlock(&priv->mutex);
        IWL_DEBUG_MAC80211(priv, "leave\n");
}

#ifdef CONFIG_PM_SLEEP

static int iwlagn_mac_suspend(struct ieee80211_hw *hw,
                              struct cfg80211_wowlan *wowlan)
{
        struct iwl_priv *priv = IWL_MAC80211_GET_DVM(hw);
        struct iwl_rxon_context *ctx = &priv->contexts[IWL_RXON_CTX_BSS];
        int ret;

        if (WARN_ON(!wowlan))
                return -EINVAL;

        IWL_DEBUG_MAC80211(priv, "enter\n");
        mutex_lock(&priv->mutex);

        /* Don't attempt WoWLAN when not associated, tear down instead. */
        if (!ctx->vif || ctx->vif->type != NL80211_IFTYPE_STATION ||
            !iwl_is_associated_ctx(ctx)) {
                ret = 1;
                goto out;
        }

        ret = iwlagn_suspend(priv, wowlan);
        if (ret)
                goto error;

        /* let the ucode operate on its own */
        iwl_write32(priv->trans, CSR_UCODE_DRV_GP1_SET,
                    CSR_UCODE_DRV_GP1_BIT_D3_CFG_COMPLETE);

        iwl_trans_d3_suspend(priv->trans, false, true);

        goto out;

 error:
        priv->wowlan = false;
        iwlagn_prepare_restart(priv);
        ieee80211_restart_hw(priv->hw);
 out:
        mutex_unlock(&priv->mutex);
        IWL_DEBUG_MAC80211(priv, "leave\n");

        return ret;
}

struct iwl_resume_data {
        struct iwl_priv *priv;
        struct iwlagn_wowlan_status *cmd;
        bool valid;
};

static bool iwl_resume_status_fn(struct iwl_notif_wait_data *notif_wait,
                                 struct iwl_rx_packet *pkt, void *data)
{
        struct iwl_resume_data *resume_data = data;
        struct iwl_priv *priv = resume_data->priv;

        if (iwl_rx_packet_payload_len(pkt) != sizeof(*resume_data->cmd)) {
                IWL_ERR(priv, "rx wrong size data\n");
                return true;
        }
        memcpy(resume_data->cmd, pkt->data, sizeof(*resume_data->cmd));
        resume_data->valid = true;

        return true;
}

static int iwlagn_mac_resume(struct ieee80211_hw *hw)
{
        struct iwl_priv *priv = IWL_MAC80211_GET_DVM(hw);
        struct iwl_rxon_context *ctx = &priv->contexts[IWL_RXON_CTX_BSS];
        struct ieee80211_vif *vif;
        u32 base;
        int ret;
        enum iwl_d3_status d3_status;
        struct error_table_start {
                /* cf. struct iwl_error_event_table */
                u32 valid;
                u32 error_id;
        } err_info;
        struct iwl_notification_wait status_wait;
        static const u16 status_cmd[] = {
                REPLY_WOWLAN_GET_STATUS,
        };
        struct iwlagn_wowlan_status status_data = {};
        struct iwl_resume_data resume_data = {
                .priv = priv,
                .cmd = &status_data,
                .valid = false,
        };
        struct cfg80211_wowlan_wakeup wakeup = {
                .pattern_idx = -1,
        };
#ifdef CONFIG_IWLWIFI_DEBUGFS
        const struct fw_img *img;
#endif

        IWL_DEBUG_MAC80211(priv, "enter\n");
        mutex_lock(&priv->mutex);

        /* we'll clear ctx->vif during iwlagn_prepare_restart() */
        vif = ctx->vif;

        ret = iwl_trans_d3_resume(priv->trans, &d3_status, false, true);
        if (ret)
                goto out_unlock;

        if (d3_status != IWL_D3_STATUS_ALIVE) {
                IWL_INFO(priv, "Device was reset during suspend\n");
                goto out_unlock;
        }

        /* uCode is no longer operating by itself */
        iwl_write32(priv->trans, CSR_UCODE_DRV_GP1_CLR,
                    CSR_UCODE_DRV_GP1_BIT_D3_CFG_COMPLETE);

        base = priv->device_pointers.error_event_table;
        if (!iwlagn_hw_valid_rtc_data_addr(base)) {
                IWL_WARN(priv, "Invalid error table during resume!\n");
                goto out_unlock;
        }

        iwl_trans_read_mem_bytes(priv->trans, base,
                                 &err_info, sizeof(err_info));

        if (err_info.valid) {
                IWL_INFO(priv, "error table is valid (%d, 0x%x)\n",
                         err_info.valid, err_info.error_id);
                if (err_info.error_id == RF_KILL_INDICATOR_FOR_WOWLAN) {
                        wakeup.rfkill_release = true;
                        ieee80211_report_wowlan_wakeup(vif, &wakeup,
                                                       GFP_KERNEL);
                }
                goto out_unlock;
        }

#ifdef CONFIG_IWLWIFI_DEBUGFS
        img = &priv->fw->img[IWL_UCODE_WOWLAN];
        if (!priv->wowlan_sram)
                priv->wowlan_sram =
                        kzalloc(img->sec[IWL_UCODE_SECTION_DATA].len,
                                GFP_KERNEL);

        if (priv->wowlan_sram)
                iwl_trans_read_mem(priv->trans, 0x800000,
                                   priv->wowlan_sram,
                                   img->sec[IWL_UCODE_SECTION_DATA].len / 4);
#endif

        /*
         * This is very strange. The GET_STATUS command is sent but the device
         * doesn't reply properly, it seems it doesn't close the RBD so one is
         * always left open ... As a result, we need to send another command
         * and have to reset the driver afterwards. As we need to switch to
         * runtime firmware again that'll happen.
         */

        iwl_init_notification_wait(&priv->notif_wait, &status_wait, status_cmd,
                                   ARRAY_SIZE(status_cmd), iwl_resume_status_fn,
                                   &resume_data);

        iwl_dvm_send_cmd_pdu(priv, REPLY_WOWLAN_GET_STATUS, CMD_ASYNC, 0, NULL);
        iwl_dvm_send_cmd_pdu(priv, REPLY_ECHO, CMD_ASYNC, 0, NULL);
        /* an RBD is left open in the firmware now! */

        ret = iwl_wait_notification(&priv->notif_wait, &status_wait, HZ/5);
        if (ret)
                goto out_unlock;

        if (resume_data.valid && priv->contexts[IWL_RXON_CTX_BSS].vif) {
                u32 reasons = le32_to_cpu(status_data.wakeup_reason);
                struct cfg80211_wowlan_wakeup *wakeup_report;

                IWL_INFO(priv, "WoWLAN wakeup reason(s): 0x%.8x\n", reasons);

                if (reasons) {
                        if (reasons & IWLAGN_WOWLAN_WAKEUP_MAGIC_PACKET)
                                wakeup.magic_pkt = true;
                        if (reasons & IWLAGN_WOWLAN_WAKEUP_PATTERN_MATCH)
                                wakeup.pattern_idx = status_data.pattern_number;
                        if (reasons & (IWLAGN_WOWLAN_WAKEUP_BEACON_MISS |
                                       IWLAGN_WOWLAN_WAKEUP_LINK_CHANGE))
                                wakeup.disconnect = true;
                        if (reasons & IWLAGN_WOWLAN_WAKEUP_GTK_REKEY_FAIL)
                                wakeup.gtk_rekey_failure = true;
                        if (reasons & IWLAGN_WOWLAN_WAKEUP_EAP_IDENT_REQ)
                                wakeup.eap_identity_req = true;
                        if (reasons & IWLAGN_WOWLAN_WAKEUP_4WAY_HANDSHAKE)
                                wakeup.four_way_handshake = true;
                        wakeup_report = &wakeup;
                } else {
                        wakeup_report = NULL;
                }

                ieee80211_report_wowlan_wakeup(vif, wakeup_report, GFP_KERNEL);
        }

        priv->wowlan = false;

        iwlagn_prepare_restart(priv);

        memset((void *)&ctx->active, 0, sizeof(ctx->active));
        iwl_connection_init_rx_config(priv, ctx);
        iwlagn_set_rxon_chain(priv, ctx);

 out_unlock:
        mutex_unlock(&priv->mutex);
        IWL_DEBUG_MAC80211(priv, "leave\n");

        ieee80211_resume_disconnect(vif);

        return 1;
}

static void iwlagn_mac_set_wakeup(struct ieee80211_hw *hw, bool enabled)
{
        struct iwl_priv *priv = IWL_MAC80211_GET_DVM(hw);

        device_set_wakeup_enable(priv->trans->dev, enabled);
}
#endif

static void iwlagn_mac_tx(struct ieee80211_hw *hw,
                          struct ieee80211_tx_control *control,
                          struct sk_buff *skb)
{
        struct iwl_priv *priv = IWL_MAC80211_GET_DVM(hw);

        if (iwlagn_tx_skb(priv, control->sta, skb))
                ieee80211_free_txskb(hw, skb);
}

static void iwlagn_mac_update_tkip_key(struct ieee80211_hw *hw,
                                       struct ieee80211_vif *vif,
                                       struct ieee80211_key_conf *keyconf,
                                       struct ieee80211_sta *sta,
                                       u32 iv32, u16 *phase1key)
{
        struct iwl_priv *priv = IWL_MAC80211_GET_DVM(hw);

        iwl_update_tkip_key(priv, vif, keyconf, sta, iv32, phase1key);
}

static int iwlagn_mac_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 iwl_priv *priv = IWL_MAC80211_GET_DVM(hw);
        struct iwl_vif_priv *vif_priv = (void *)vif->drv_priv;
        struct iwl_rxon_context *ctx = vif_priv->ctx;
        int ret;
        bool is_default_wep_key = false;

        IWL_DEBUG_MAC80211(priv, "enter\n");

        if (iwlwifi_mod_params.sw_crypto) {
                IWL_DEBUG_MAC80211(priv, "leave - hwcrypto disabled\n");
                return -EOPNOTSUPP;
        }

        switch (key->cipher) {
        case WLAN_CIPHER_SUITE_TKIP:
                key->flags |= IEEE80211_KEY_FLAG_GENERATE_MMIC;
                /* fall through */
        case WLAN_CIPHER_SUITE_CCMP:
                key->flags |= IEEE80211_KEY_FLAG_GENERATE_IV;
                break;
        default:
                break;
        }

        /*
         * We could program these keys into the hardware as well, but we
         * don't expect much multicast traffic in IBSS and having keys
         * for more stations is probably more useful.
         *
         * Mark key TX-only and return 0.
         */
        if (vif->type == NL80211_IFTYPE_ADHOC &&
            !(key->flags & IEEE80211_KEY_FLAG_PAIRWISE)) {
                key->hw_key_idx = WEP_INVALID_OFFSET;
                return 0;
        }

        /* If they key was TX-only, accept deletion */
        if (cmd == DISABLE_KEY && key->hw_key_idx == WEP_INVALID_OFFSET)
                return 0;

        mutex_lock(&priv->mutex);
        iwl_scan_cancel_timeout(priv, 100);

        BUILD_BUG_ON(WEP_INVALID_OFFSET == IWLAGN_HW_KEY_DEFAULT);

        /*
         * If we are getting WEP group key and we didn't receive any key mapping
         * so far, we are in legacy wep mode (group key only), otherwise we are
         * in 1X mode.
         * In legacy wep mode, we use another host command to the uCode.
         */
        if ((key->cipher == WLAN_CIPHER_SUITE_WEP40 ||
             key->cipher == WLAN_CIPHER_SUITE_WEP104) && !sta) {
                if (cmd == SET_KEY)
                        is_default_wep_key = !ctx->key_mapping_keys;
                else
                        is_default_wep_key =
                                key->hw_key_idx == IWLAGN_HW_KEY_DEFAULT;
        }


        switch (cmd) {
        case SET_KEY:
                if (is_default_wep_key) {
                        ret = iwl_set_default_wep_key(priv, vif_priv->ctx, key);
                        break;
                }
                ret = iwl_set_dynamic_key(priv, vif_priv->ctx, key, sta);
                if (ret) {
                        /*
                         * can't add key for RX, but we don't need it
                         * in the device for TX so still return 0
                         */
                        ret = 0;
                        key->hw_key_idx = WEP_INVALID_OFFSET;
                }

                IWL_DEBUG_MAC80211(priv, "enable hwcrypto key\n");
                break;
        case DISABLE_KEY:
                if (is_default_wep_key)
                        ret = iwl_remove_default_wep_key(priv, ctx, key);
                else
                        ret = iwl_remove_dynamic_key(priv, ctx, key, sta);

                IWL_DEBUG_MAC80211(priv, "disable hwcrypto key\n");
                break;
        default:
                ret = -EINVAL;
        }

        mutex_unlock(&priv->mutex);
        IWL_DEBUG_MAC80211(priv, "leave\n");

        return ret;
}

static inline bool iwl_enable_rx_ampdu(const struct iwl_cfg *cfg)
{
        if (iwlwifi_mod_params.disable_11n & IWL_DISABLE_HT_RXAGG)
                return false;
        return true;
}

static inline bool iwl_enable_tx_ampdu(const struct iwl_cfg *cfg)
{
        if (iwlwifi_mod_params.disable_11n & IWL_DISABLE_HT_TXAGG)
                return false;
        if (iwlwifi_mod_params.disable_11n & IWL_ENABLE_HT_TXAGG)
                return true;

        /* disabled by default */
        return false;
}

static int iwlagn_mac_ampdu_action(struct ieee80211_hw *hw,
                                   struct ieee80211_vif *vif,
                                   struct ieee80211_ampdu_params *params)
{
        struct iwl_priv *priv = IWL_MAC80211_GET_DVM(hw);
        int ret = -EINVAL;
        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;
        struct iwl_station_priv *sta_priv = (void *) sta->drv_priv;

        IWL_DEBUG_HT(priv, "A-MPDU action on addr %pM tid %d\n",
                     sta->addr, tid);

        if (!(priv->nvm_data->sku_cap_11n_enable))
                return -EACCES;

        IWL_DEBUG_MAC80211(priv, "enter\n");
        mutex_lock(&priv->mutex);

        switch (action) {
        case IEEE80211_AMPDU_RX_START:
                if (!iwl_enable_rx_ampdu(priv->cfg))
                        break;
                IWL_DEBUG_HT(priv, "start Rx\n");
                ret = iwl_sta_rx_agg_start(priv, sta, tid, *ssn);
                break;
        case IEEE80211_AMPDU_RX_STOP:
                IWL_DEBUG_HT(priv, "stop Rx\n");
                ret = iwl_sta_rx_agg_stop(priv, sta, tid);
                break;
        case IEEE80211_AMPDU_TX_START:
                if (!priv->trans->ops->txq_enable)
                        break;
                if (!iwl_enable_tx_ampdu(priv->cfg))
                        break;
                IWL_DEBUG_HT(priv, "start Tx\n");
                ret = iwlagn_tx_agg_start(priv, vif, sta, tid, ssn);
                break;
        case IEEE80211_AMPDU_TX_STOP_FLUSH:
        case IEEE80211_AMPDU_TX_STOP_FLUSH_CONT:
                IWL_DEBUG_HT(priv, "Flush Tx\n");
                ret = iwlagn_tx_agg_flush(priv, vif, sta, tid);
                break;
        case IEEE80211_AMPDU_TX_STOP_CONT:
                IWL_DEBUG_HT(priv, "stop Tx\n");
                ret = iwlagn_tx_agg_stop(priv, vif, sta, tid);
                if ((ret == 0) && (priv->agg_tids_count > 0)) {
                        priv->agg_tids_count--;
                        IWL_DEBUG_HT(priv, "priv->agg_tids_count = %u\n",
                                     priv->agg_tids_count);
                }
                if (!priv->agg_tids_count &&
                    priv->hw_params.use_rts_for_aggregation) {
                        /*
                         * switch off RTS/CTS if it was previously enabled
                         */
                        sta_priv->lq_sta.lq.general_params.flags &=
                                ~LINK_QUAL_FLAGS_SET_STA_TLC_RTS_MSK;
                        iwl_send_lq_cmd(priv, iwl_rxon_ctx_from_vif(vif),
                                        &sta_priv->lq_sta.lq, CMD_ASYNC, false);
                }
                break;
        case IEEE80211_AMPDU_TX_OPERATIONAL:
                ret = iwlagn_tx_agg_oper(priv, vif, sta, tid, buf_size);
                break;
        }
        mutex_unlock(&priv->mutex);
        IWL_DEBUG_MAC80211(priv, "leave\n");
        return ret;
}

static int iwlagn_mac_sta_add(struct ieee80211_hw *hw,
                              struct ieee80211_vif *vif,
                              struct ieee80211_sta *sta)
{
        struct iwl_priv *priv = IWL_MAC80211_GET_DVM(hw);
        struct iwl_station_priv *sta_priv = (void *)sta->drv_priv;
        struct iwl_vif_priv *vif_priv = (void *)vif->drv_priv;
        bool is_ap = vif->type == NL80211_IFTYPE_STATION;
        int ret;
        u8 sta_id;

        IWL_DEBUG_INFO(priv, "proceeding to add station %pM\n",
                        sta->addr);
        sta_priv->sta_id = IWL_INVALID_STATION;

        atomic_set(&sta_priv->pending_frames, 0);
        if (vif->type == NL80211_IFTYPE_AP)
                sta_priv->client = true;

        ret = iwl_add_station_common(priv, vif_priv->ctx, sta->addr,
                                     is_ap, sta, &sta_id);
        if (ret) {
                IWL_ERR(priv, "Unable to add station %pM (%d)\n",
                        sta->addr, ret);
                /* Should we return success if return code is EEXIST ? */
                return ret;
        }

        sta_priv->sta_id = sta_id;

        return 0;
}

static int iwlagn_mac_sta_remove(struct ieee80211_hw *hw,
                                 struct ieee80211_vif *vif,
                                 struct ieee80211_sta *sta)
{
        struct iwl_priv *priv = IWL_MAC80211_GET_DVM(hw);
        struct iwl_station_priv *sta_priv = (void *)sta->drv_priv;
        int ret;

        IWL_DEBUG_INFO(priv, "proceeding to remove station %pM\n", sta->addr);

        if (vif->type == NL80211_IFTYPE_STATION) {
                /*
                 * Station will be removed from device when the RXON
                 * is set to unassociated -- just deactivate it here
                 * to avoid re-programming it.
                 */
                ret = 0;
                iwl_deactivate_station(priv, sta_priv->sta_id, sta->addr);
        } else {
                ret = iwl_remove_station(priv, sta_priv->sta_id, sta->addr);
                if (ret)
                        IWL_DEBUG_QUIET_RFKILL(priv,
                                "Error removing station %pM\n", sta->addr);
        }
        return ret;
}

static int iwlagn_mac_sta_state(struct ieee80211_hw *hw,
                                struct ieee80211_vif *vif,
                                struct ieee80211_sta *sta,
                                enum ieee80211_sta_state old_state,
                                enum ieee80211_sta_state new_state)
{
        struct iwl_priv *priv = IWL_MAC80211_GET_DVM(hw);
        struct iwl_vif_priv *vif_priv = (void *)vif->drv_priv;
        enum {
                NONE, ADD, REMOVE, HT_RATE_INIT, ADD_RATE_INIT,
        } op = NONE;
        int ret;

        IWL_DEBUG_MAC80211(priv, "station %pM state change %d->%d\n",
                           sta->addr, old_state, new_state);

        mutex_lock(&priv->mutex);
        if (vif->type == NL80211_IFTYPE_STATION) {
                if (old_state == IEEE80211_STA_NOTEXIST &&
                    new_state == IEEE80211_STA_NONE)
                        op = ADD;
                else if (old_state == IEEE80211_STA_NONE &&
                         new_state == IEEE80211_STA_NOTEXIST)
                        op = REMOVE;
                else if (old_state == IEEE80211_STA_AUTH &&
                         new_state == IEEE80211_STA_ASSOC)
                        op = HT_RATE_INIT;
        } else {
                if (old_state == IEEE80211_STA_AUTH &&
                    new_state == IEEE80211_STA_ASSOC)
                        op = ADD_RATE_INIT;
                else if (old_state == IEEE80211_STA_ASSOC &&
                         new_state == IEEE80211_STA_AUTH)
                        op = REMOVE;
        }

        switch (op) {
        case ADD:
                ret = iwlagn_mac_sta_add(hw, vif, sta);
                if (ret)
                        break;
                /*
                 * Clear the in-progress flag, the AP station entry was added
                 * but we'll initialize LQ only when we've associated (which
                 * would also clear the in-progress flag). This is necessary
                 * in case we never initialize LQ because association fails.
                 */
                spin_lock_bh(&priv->sta_lock);
                priv->stations[iwl_sta_id(sta)].used &=
                        ~IWL_STA_UCODE_INPROGRESS;
                spin_unlock_bh(&priv->sta_lock);
                break;
        case REMOVE:
                ret = iwlagn_mac_sta_remove(hw, vif, sta);
                break;
        case ADD_RATE_INIT:
                ret = iwlagn_mac_sta_add(hw, vif, sta);
                if (ret)
                        break;
                /* Initialize rate scaling */
                IWL_DEBUG_INFO(priv,
                               "Initializing rate scaling for station %pM\n",
                               sta->addr);
                iwl_rs_rate_init(priv, sta, iwl_sta_id(sta));
                ret = 0;
                break;
        case HT_RATE_INIT:
                /* Initialize rate scaling */
                ret = iwl_sta_update_ht(priv, vif_priv->ctx, sta);
                if (ret)
                        break;
                IWL_DEBUG_INFO(priv,
                               "Initializing rate scaling for station %pM\n",
                               sta->addr);
                iwl_rs_rate_init(priv, sta, iwl_sta_id(sta));
                ret = 0;
                break;
        default:
                ret = 0;
                break;
        }

        /*
         * mac80211 might WARN if we fail, but due the way we
         * (badly) handle hard rfkill, we might fail here
         */
        if (iwl_is_rfkill(priv))
                ret = 0;

        mutex_unlock(&priv->mutex);
        IWL_DEBUG_MAC80211(priv, "leave\n");

        return ret;
}

static void iwlagn_mac_channel_switch(struct ieee80211_hw *hw,
                                      struct ieee80211_vif *vif,
                                      struct ieee80211_channel_switch *ch_switch)
{
        struct iwl_priv *priv = IWL_MAC80211_GET_DVM(hw);
        struct ieee80211_conf *conf = &hw->conf;
        struct ieee80211_channel *channel = ch_switch->chandef.chan;
        struct iwl_ht_config *ht_conf = &priv->current_ht_config;
        /*
         * MULTI-FIXME
         * When we add support for multiple interfaces, we need to
         * revisit this. The channel switch command in the device
         * only affects the BSS context, but what does that really
         * mean? And what if we get a CSA on the second interface?
         * This needs a lot of work.
         */
        struct iwl_rxon_context *ctx = &priv->contexts[IWL_RXON_CTX_BSS];
        u16 ch;

        IWL_DEBUG_MAC80211(priv, "enter\n");

        mutex_lock(&priv->mutex);

        if (iwl_is_rfkill(priv))
                goto out;

        if (test_bit(STATUS_EXIT_PENDING, &priv->status) ||
            test_bit(STATUS_SCANNING, &priv->status) ||
            test_bit(STATUS_CHANNEL_SWITCH_PENDING, &priv->status))
                goto out;

        if (!iwl_is_associated_ctx(ctx))
                goto out;

        if (!priv->lib->set_channel_switch)
                goto out;

        ch = channel->hw_value;
        if (le16_to_cpu(ctx->active.channel) == ch)

                goto out;

        priv->current_ht_config.smps = conf->smps_mode;

        /* Configure HT40 channels */
        switch (cfg80211_get_chandef_type(&ch_switch->chandef)) {
        case NL80211_CHAN_NO_HT:
        case NL80211_CHAN_HT20:
                ctx->ht.is_40mhz = false;
                ctx->ht.extension_chan_offset = IEEE80211_HT_PARAM_CHA_SEC_NONE;
                break;
        case NL80211_CHAN_HT40MINUS:
                ctx->ht.extension_chan_offset = IEEE80211_HT_PARAM_CHA_SEC_BELOW;
                ctx->ht.is_40mhz = true;
                break;
        case NL80211_CHAN_HT40PLUS:
                ctx->ht.extension_chan_offset = IEEE80211_HT_PARAM_CHA_SEC_ABOVE;
                ctx->ht.is_40mhz = true;
                break;
        }

        if ((le16_to_cpu(ctx->staging.channel) != ch))
                ctx->staging.flags = 0;

        iwl_set_rxon_channel(priv, channel, ctx);
        iwl_set_rxon_ht(priv, ht_conf);
        iwl_set_flags_for_band(priv, ctx, channel->band, ctx->vif);

        /*
         * at this point, staging_rxon has the
         * configuration for channel switch
         */
        set_bit(STATUS_CHANNEL_SWITCH_PENDING, &priv->status);
        priv->switch_channel = cpu_to_le16(ch);
        if (priv->lib->set_channel_switch(priv, ch_switch)) {
                clear_bit(STATUS_CHANNEL_SWITCH_PENDING, &priv->status);
                priv->switch_channel = 0;
                ieee80211_chswitch_done(ctx->vif, false);
        }

out:
        mutex_unlock(&priv->mutex);
        IWL_DEBUG_MAC80211(priv, "leave\n");
}

void iwl_chswitch_done(struct iwl_priv *priv, bool is_success)
{
        /*
         * MULTI-FIXME
         * See iwlagn_mac_channel_switch.
         */
        struct iwl_rxon_context *ctx = &priv->contexts[IWL_RXON_CTX_BSS];

        if (test_bit(STATUS_EXIT_PENDING, &priv->status))
                return;

        if (!test_and_clear_bit(STATUS_CHANNEL_SWITCH_PENDING, &priv->status))
                return;

        if (ctx->vif)
                ieee80211_chswitch_done(ctx->vif, is_success);
}

static void iwlagn_configure_filter(struct ieee80211_hw *hw,
                                    unsigned int changed_flags,
                                    unsigned int *total_flags,
                                    u64 multicast)
{
        struct iwl_priv *priv = IWL_MAC80211_GET_DVM(hw);
        __le32 filter_or = 0, filter_nand = 0;
        struct iwl_rxon_context *ctx;

#define CHK(test, flag) do { \
        if (*total_flags & (test))              \
                filter_or |= (flag);            \
        else                                    \
                filter_nand |= (flag);          \
        } while (0)

        IWL_DEBUG_MAC80211(priv, "Enter: changed: 0x%x, total: 0x%x\n",
                        changed_flags, *total_flags);

        CHK(FIF_OTHER_BSS, RXON_FILTER_PROMISC_MSK);
        /* Setting _just_ RXON_FILTER_CTL2HOST_MSK causes FH errors */
        CHK(FIF_CONTROL, RXON_FILTER_CTL2HOST_MSK | RXON_FILTER_PROMISC_MSK);
        CHK(FIF_BCN_PRBRESP_PROMISC, RXON_FILTER_BCON_AWARE_MSK);

#undef CHK

        mutex_lock(&priv->mutex);

        for_each_context(priv, ctx) {
                ctx->staging.filter_flags &= ~filter_nand;
                ctx->staging.filter_flags |= filter_or;

                /*
                 * Not committing directly because hardware can perform a scan,
                 * but we'll eventually commit the filter flags change anyway.
                 */
        }

        mutex_unlock(&priv->mutex);

        /*
         * Receiving all multicast frames is always enabled by the
         * default flags setup in iwl_connection_init_rx_config()
         * since we currently do not support programming multicast
         * filters into the device.
         */
        *total_flags &= FIF_OTHER_BSS | FIF_ALLMULTI |
                        FIF_BCN_PRBRESP_PROMISC | FIF_CONTROL;
}

static void iwlagn_mac_flush(struct ieee80211_hw *hw, struct ieee80211_vif *vif,
                             u32 queues, bool drop)
{
        struct iwl_priv *priv = IWL_MAC80211_GET_DVM(hw);
        u32 scd_queues;

        mutex_lock(&priv->mutex);
        IWL_DEBUG_MAC80211(priv, "enter\n");

        if (test_bit(STATUS_EXIT_PENDING, &priv->status)) {
                IWL_DEBUG_TX(priv, "Aborting flush due to device shutdown\n");
                goto done;
        }
        if (iwl_is_rfkill(priv)) {
                IWL_DEBUG_TX(priv, "Aborting flush due to RF Kill\n");
                goto done;
        }

        scd_queues = BIT(priv->cfg->base_params->num_of_queues) - 1;
        scd_queues &= ~(BIT(IWL_IPAN_CMD_QUEUE_NUM) |
                        BIT(IWL_DEFAULT_CMD_QUEUE_NUM));

        if (drop) {
                IWL_DEBUG_TX_QUEUES(priv, "Flushing SCD queues: 0x%x\n",
                                    scd_queues);
                if (iwlagn_txfifo_flush(priv, scd_queues)) {
                        IWL_ERR(priv, "flush request fail\n");
                        goto done;
                }
        }

        IWL_DEBUG_TX_QUEUES(priv, "wait transmit/flush all frames\n");
        iwl_trans_wait_tx_queue_empty(priv->trans, scd_queues);
done:
        mutex_unlock(&priv->mutex);
        IWL_DEBUG_MAC80211(priv, "leave\n");
}

static void iwlagn_mac_event_callback(struct ieee80211_hw *hw,
                                      struct ieee80211_vif *vif,
                                      const struct ieee80211_event *event)
{
        struct iwl_priv *priv = IWL_MAC80211_GET_DVM(hw);

        if (event->type != RSSI_EVENT)
                return;

        IWL_DEBUG_MAC80211(priv, "enter\n");

        if (priv->lib->bt_params &&
            priv->lib->bt_params->advanced_bt_coexist) {
                if (event->u.rssi.data == RSSI_EVENT_LOW)
                        priv->bt_enable_pspoll = true;
                else if (event->u.rssi.data == RSSI_EVENT_HIGH)
                        priv->bt_enable_pspoll = false;

                queue_work(priv->workqueue, &priv->bt_runtime_config);
        } else {
                IWL_DEBUG_MAC80211(priv, "Advanced BT coex disabled,"
                                "ignoring RSSI callback\n");
        }

        IWL_DEBUG_MAC80211(priv, "leave\n");
}

static int iwlagn_mac_set_tim(struct ieee80211_hw *hw,
                              struct ieee80211_sta *sta, bool set)
{
        struct iwl_priv *priv = IWL_MAC80211_GET_DVM(hw);

        queue_work(priv->workqueue, &priv->beacon_update);

        return 0;
}

static int iwlagn_mac_conf_tx(struct ieee80211_hw *hw,
                              struct ieee80211_vif *vif, u16 queue,
                              const struct ieee80211_tx_queue_params *params)
{
        struct iwl_priv *priv = IWL_MAC80211_GET_DVM(hw);
        struct iwl_vif_priv *vif_priv = (void *)vif->drv_priv;
        struct iwl_rxon_context *ctx = vif_priv->ctx;
        int q;

        if (WARN_ON(!ctx))
                return -EINVAL;

        IWL_DEBUG_MAC80211(priv, "enter\n");

        if (!iwl_is_ready_rf(priv)) {
                IWL_DEBUG_MAC80211(priv, "leave - RF not ready\n");
                return -EIO;
        }

        if (queue >= AC_NUM) {
                IWL_DEBUG_MAC80211(priv, "leave - queue >= AC_NUM %d\n", queue);
                return 0;
        }

        q = AC_NUM - 1 - queue;

        mutex_lock(&priv->mutex);

        ctx->qos_data.def_qos_parm.ac[q].cw_min =
                cpu_to_le16(params->cw_min);
        ctx->qos_data.def_qos_parm.ac[q].cw_max =
                cpu_to_le16(params->cw_max);
        ctx->qos_data.def_qos_parm.ac[q].aifsn = params->aifs;
        ctx->qos_data.def_qos_parm.ac[q].edca_txop =
                        cpu_to_le16((params->txop * 32));

        ctx->qos_data.def_qos_parm.ac[q].reserved1 = 0;

        mutex_unlock(&priv->mutex);

        IWL_DEBUG_MAC80211(priv, "leave\n");
        return 0;
}

static int iwlagn_mac_tx_last_beacon(struct ieee80211_hw *hw)
{
        struct iwl_priv *priv = IWL_MAC80211_GET_DVM(hw);

        return priv->ibss_manager == IWL_IBSS_MANAGER;
}

static int iwl_set_mode(struct iwl_priv *priv, struct iwl_rxon_context *ctx)
{
        iwl_connection_init_rx_config(priv, ctx);

        iwlagn_set_rxon_chain(priv, ctx);

        return iwlagn_commit_rxon(priv, ctx);
}

static int iwl_setup_interface(struct iwl_priv *priv,
                               struct iwl_rxon_context *ctx)
{
        struct ieee80211_vif *vif = ctx->vif;
        int err, ac;

        lockdep_assert_held(&priv->mutex);

        /*
         * This variable will be correct only when there's just
         * a single context, but all code using it is for hardware
         * that supports only one context.
         */
        priv->iw_mode = vif->type;

        ctx->is_active = true;

        err = iwl_set_mode(priv, ctx);
        if (err) {
                if (!ctx->always_active)
                        ctx->is_active = false;
                return err;
        }

        if (priv->lib->bt_params && priv->lib->bt_params->advanced_bt_coexist &&
            vif->type == NL80211_IFTYPE_ADHOC) {
                /*
                 * pretend to have high BT traffic as long as we
                 * are operating in IBSS mode, as this will cause
                 * the rate scaling etc. to behave as intended.
                 */
                priv->bt_traffic_load = IWL_BT_COEX_TRAFFIC_LOAD_HIGH;
        }

        /* set up queue mappings */
        for (ac = 0; ac < IEEE80211_NUM_ACS; ac++)
                vif->hw_queue[ac] = ctx->ac_to_queue[ac];

        if (vif->type == NL80211_IFTYPE_AP)
                vif->cab_queue = ctx->mcast_queue;
        else
                vif->cab_queue = IEEE80211_INVAL_HW_QUEUE;

        return 0;
}

static int iwlagn_mac_add_interface(struct ieee80211_hw *hw,
                                    struct ieee80211_vif *vif)
{
        struct iwl_priv *priv = IWL_MAC80211_GET_DVM(hw);
        struct iwl_vif_priv *vif_priv = (void *)vif->drv_priv;
        struct iwl_rxon_context *tmp, *ctx = NULL;
        int err;
        enum nl80211_iftype viftype = ieee80211_vif_type_p2p(vif);
        bool reset = false;

        IWL_DEBUG_MAC80211(priv, "enter: type %d, addr %pM\n",
                           viftype, vif->addr);

        mutex_lock(&priv->mutex);

        if (!iwl_is_ready_rf(priv)) {
                IWL_WARN(priv, "Try to add interface when device not ready\n");
                err = -EINVAL;
                goto out;
        }

        for_each_context(priv, tmp) {
                u32 possible_modes =
                        tmp->interface_modes | tmp->exclusive_interface_modes;

                if (tmp->vif) {
                        /* On reset we need to add the same interface again */
                        if (tmp->vif == vif) {
                                reset = true;
                                ctx = tmp;
                                break;
                        }

                        /* check if this busy context is exclusive */
                        if (tmp->exclusive_interface_modes &
                                                BIT(tmp->vif->type)) {
                                err = -EINVAL;
                                goto out;
                        }
                        continue;
                }

                if (!(possible_modes & BIT(viftype)))
                        continue;

                /* have maybe usable context w/o interface */
                ctx = tmp;
                break;
        }

        if (!ctx) {
                err = -EOPNOTSUPP;
                goto out;
        }

        vif_priv->ctx = ctx;
        ctx->vif = vif;

        /*
         * In SNIFFER device type, the firmware reports the FCS to
         * the host, rather than snipping it off. Unfortunately,
         * mac80211 doesn't (yet) provide a per-packet flag for
         * this, so that we have to set the hardware flag based
         * on the interfaces added. As the monitor interface can
         * only be present by itself, and will be removed before
         * other interfaces are added, this is safe.
         */
        if (vif->type == NL80211_IFTYPE_MONITOR)
                ieee80211_hw_set(priv->hw, RX_INCLUDES_FCS);
        else
                __clear_bit(IEEE80211_HW_RX_INCLUDES_FCS, priv->hw->flags);

        err = iwl_setup_interface(priv, ctx);
        if (!err || reset)
                goto out;

        ctx->vif = NULL;
        priv->iw_mode = NL80211_IFTYPE_STATION;
 out:
        mutex_unlock(&priv->mutex);

        IWL_DEBUG_MAC80211(priv, "leave\n");
        return err;
}

static void iwl_teardown_interface(struct iwl_priv *priv,
                                   struct ieee80211_vif *vif,
                                   bool mode_change)
{
        struct iwl_rxon_context *ctx = iwl_rxon_ctx_from_vif(vif);

        lockdep_assert_held(&priv->mutex);

        if (priv->scan_vif == vif) {
                iwl_scan_cancel_timeout(priv, 200);
                iwl_force_scan_end(priv);
        }

        if (!mode_change) {
                iwl_set_mode(priv, ctx);
                if (!ctx->always_active)
                        ctx->is_active = false;
        }

        /*
         * When removing the IBSS interface, overwrite the
         * BT traffic load with the stored one from the last
         * notification, if any. If this is a device that
         * doesn't implement this, this has no effect since
         * both values are the same and zero.
         */
        if (vif->type == NL80211_IFTYPE_ADHOC)
                priv->bt_traffic_load = priv->last_bt_traffic_load;
}

static void iwlagn_mac_remove_interface(struct ieee80211_hw *hw,
                              struct ieee80211_vif *vif)
{
        struct iwl_priv *priv = IWL_MAC80211_GET_DVM(hw);
        struct iwl_rxon_context *ctx = iwl_rxon_ctx_from_vif(vif);

        IWL_DEBUG_MAC80211(priv, "enter\n");

        mutex_lock(&priv->mutex);

        WARN_ON(ctx->vif != vif);
        ctx->vif = NULL;

        iwl_teardown_interface(priv, vif, false);

        mutex_unlock(&priv->mutex);

        IWL_DEBUG_MAC80211(priv, "leave\n");

}

static int iwlagn_mac_change_interface(struct ieee80211_hw *hw,
                                       struct ieee80211_vif *vif,
                                       enum nl80211_iftype newtype, bool newp2p)
{
        struct iwl_priv *priv = IWL_MAC80211_GET_DVM(hw);
        struct iwl_rxon_context *ctx, *tmp;
        enum nl80211_iftype newviftype = newtype;
        u32 interface_modes;
        int err;

        IWL_DEBUG_MAC80211(priv, "enter\n");

        newtype = ieee80211_iftype_p2p(newtype, newp2p);

        mutex_lock(&priv->mutex);

        ctx = iwl_rxon_ctx_from_vif(vif);

        /*
         * To simplify this code, only support changes on the
         * BSS context. The PAN context is usually reassigned
         * by creating/removing P2P interfaces anyway.
         */
        if (ctx->ctxid != IWL_RXON_CTX_BSS) {
                err = -EBUSY;
                goto out;
        }

        if (!ctx->vif || !iwl_is_ready_rf(priv)) {
                /*
                 * Huh? But wait ... this can maybe happen when
                 * we're in the middle of a firmware restart!
                 */
                err = -EBUSY;
                goto out;
        }

        /* Check if the switch is supported in the same context */
        interface_modes = ctx->interface_modes | ctx->exclusive_interface_modes;
        if (!(interface_modes & BIT(newtype))) {
                err = -EBUSY;
                goto out;
        }

        if (ctx->exclusive_interface_modes & BIT(newtype)) {
                for_each_context(priv, tmp) {
                        if (ctx == tmp)
                                continue;

                        if (!tmp->is_active)
                                continue;

                        /*
                         * The current mode switch would be exclusive, but
                         * another context is active ... refuse the switch.
                         */
                        err = -EBUSY;
                        goto out;
                }
        }

        /* success */
        iwl_teardown_interface(priv, vif, true);
        vif->type = newviftype;
        vif->p2p = newp2p;
        err = iwl_setup_interface(priv, ctx);
        WARN_ON(err);
        /*
         * We've switched internally, but submitting to the
         * device may have failed for some reason. Mask this
         * error, because otherwise mac80211 will not switch
         * (and set the interface type back) and we'll be
         * out of sync with it.
         */
        err = 0;

 out:
        mutex_unlock(&priv->mutex);
        IWL_DEBUG_MAC80211(priv, "leave\n");

        return err;
}

static int iwlagn_mac_hw_scan(struct ieee80211_hw *hw,
                              struct ieee80211_vif *vif,
                              struct ieee80211_scan_request *hw_req)
{
        struct iwl_priv *priv = IWL_MAC80211_GET_DVM(hw);
        struct cfg80211_scan_request *req = &hw_req->req;
        int ret;

        IWL_DEBUG_MAC80211(priv, "enter\n");

        if (req->n_channels == 0)
                return -EINVAL;

        mutex_lock(&priv->mutex);

        /*
         * If an internal scan is in progress, just set
         * up the scan_request as per above.
         */
        if (priv->scan_type != IWL_SCAN_NORMAL) {
                IWL_DEBUG_SCAN(priv,
                               "SCAN request during internal scan - defer\n");
                priv->scan_request = req;
                priv->scan_vif = vif;
                ret = 0;
        } else {
                priv->scan_request = req;
                priv->scan_vif = vif;
                /*
                 * mac80211 will only ask for one band at a time
                 * so using channels[0] here is ok
                 */
                ret = iwl_scan_initiate(priv, vif, IWL_SCAN_NORMAL,
                                        req->channels[0]->band);
                if (ret) {
                        priv->scan_request = NULL;
                        priv->scan_vif = NULL;
                }
        }

        IWL_DEBUG_MAC80211(priv, "leave\n");

        mutex_unlock(&priv->mutex);

        return ret;
}

static void iwl_sta_modify_ps_wake(struct iwl_priv *priv, int sta_id)
{
        struct iwl_addsta_cmd cmd = {
                .mode = STA_CONTROL_MODIFY_MSK,
                .station_flags_msk = STA_FLG_PWR_SAVE_MSK,
                .sta.sta_id = sta_id,
        };

        iwl_send_add_sta(priv, &cmd, CMD_ASYNC);
}

static void iwlagn_mac_sta_notify(struct ieee80211_hw *hw,
                                  struct ieee80211_vif *vif,
                                  enum sta_notify_cmd cmd,
                                  struct ieee80211_sta *sta)
{
        struct iwl_priv *priv = IWL_MAC80211_GET_DVM(hw);
        struct iwl_station_priv *sta_priv = (void *)sta->drv_priv;
        int sta_id;

        IWL_DEBUG_MAC80211(priv, "enter\n");

        switch (cmd) {
        case STA_NOTIFY_SLEEP:
                WARN_ON(!sta_priv->client);
                sta_priv->asleep = true;
                if (atomic_read(&sta_priv->pending_frames) > 0)
                        ieee80211_sta_block_awake(hw, sta, true);
                break;
        case STA_NOTIFY_AWAKE:
                WARN_ON(!sta_priv->client);
                if (!sta_priv->asleep)
                        break;
                sta_priv->asleep = false;
                sta_id = iwl_sta_id(sta);
                if (sta_id != IWL_INVALID_STATION)
                        iwl_sta_modify_ps_wake(priv, sta_id);
                break;
        default:
                break;
        }
        IWL_DEBUG_MAC80211(priv, "leave\n");
}

const struct ieee80211_ops iwlagn_hw_ops = {
        .tx = iwlagn_mac_tx,
        .start = iwlagn_mac_start,
        .stop = iwlagn_mac_stop,
#ifdef CONFIG_PM_SLEEP
        .suspend = iwlagn_mac_suspend,
        .resume = iwlagn_mac_resume,
        .set_wakeup = iwlagn_mac_set_wakeup,
#endif
        .add_interface = iwlagn_mac_add_interface,
        .remove_interface = iwlagn_mac_remove_interface,
        .change_interface = iwlagn_mac_change_interface,
        .config = iwlagn_mac_config,
        .configure_filter = iwlagn_configure_filter,
        .set_key = iwlagn_mac_set_key,
        .update_tkip_key = iwlagn_mac_update_tkip_key,
        .set_rekey_data = iwlagn_mac_set_rekey_data,
        .conf_tx = iwlagn_mac_conf_tx,
        .bss_info_changed = iwlagn_bss_info_changed,
        .ampdu_action = iwlagn_mac_ampdu_action,
        .hw_scan = iwlagn_mac_hw_scan,
        .sta_notify = iwlagn_mac_sta_notify,
        .sta_state = iwlagn_mac_sta_state,
        .channel_switch = iwlagn_mac_channel_switch,
        .flush = iwlagn_mac_flush,
        .tx_last_beacon = iwlagn_mac_tx_last_beacon,
        .event_callback = iwlagn_mac_event_callback,
        .set_tim = iwlagn_mac_set_tim,
};

/* This function both allocates and initializes hw and priv. */
struct ieee80211_hw *iwl_alloc_all(void)
{
        struct iwl_priv *priv;
        struct iwl_op_mode *op_mode;
        /* mac80211 allocates memory for this device instance, including
         *   space for this driver's private structure */
        struct ieee80211_hw *hw;

        hw = ieee80211_alloc_hw(sizeof(struct iwl_priv) +
                                sizeof(struct iwl_op_mode), &iwlagn_hw_ops);
        if (!hw)
                goto out;

        op_mode = hw->priv;
        priv = IWL_OP_MODE_GET_DVM(op_mode);
        priv->hw = hw;

out:
        return hw;
}