mwifiex: fix out of memory issue observed for USB chipsets

[deliverable/linux.git] / drivers / net / wireless / mwifiex / main.c

/*
 * Marvell Wireless LAN device driver: major functions
 *
 * Copyright (C) 2011-2014, Marvell International Ltd.
 *
 * This software file (the "File") is distributed by Marvell International
 * Ltd. under the terms of the GNU General Public License Version 2, June 1991
 * (the "License").  You may use, redistribute and/or modify this File in
 * accordance with the terms and conditions of the License, a copy of which
 * is available by writing to the Free Software Foundation, Inc.,
 * 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA or on the
 * worldwide web at http://www.gnu.org/licenses/old-licenses/gpl-2.0.txt.
 *
 * THE FILE IS DISTRIBUTED AS-IS, WITHOUT WARRANTY OF ANY KIND, AND THE
 * IMPLIED WARRANTIES OF MERCHANTABILITY OR FITNESS FOR A PARTICULAR PURPOSE
 * ARE EXPRESSLY DISCLAIMED.  The License provides additional details about
 * this warranty disclaimer.
 */

#include "main.h"
#include "wmm.h"
#include "cfg80211.h"
#include "11n.h"

#define VERSION "1.0"

const char driver_version[] = "mwifiex " VERSION " (%s) ";
static char *cal_data_cfg;
module_param(cal_data_cfg, charp, 0);

/*
 * This function registers the device and performs all the necessary
 * initializations.
 *
 * The following initialization operations are performed -
 *      - Allocate adapter structure
 *      - Save interface specific operations table in adapter
 *      - Call interface specific initialization routine
 *      - Allocate private structures
 *      - Set default adapter structure parameters
 *      - Initialize locks
 *
 * In case of any errors during inittialization, this function also ensures
 * proper cleanup before exiting.
 */
static int mwifiex_register(void *card, struct mwifiex_if_ops *if_ops,
                            void **padapter)
{
        struct mwifiex_adapter *adapter;
        int i;

        adapter = kzalloc(sizeof(struct mwifiex_adapter), GFP_KERNEL);
        if (!adapter)
                return -ENOMEM;

        *padapter = adapter;
        adapter->card = card;

        /* Save interface specific operations in adapter */
        memmove(&adapter->if_ops, if_ops, sizeof(struct mwifiex_if_ops));

        /* card specific initialization has been deferred until now .. */
        if (adapter->if_ops.init_if)
                if (adapter->if_ops.init_if(adapter))
                        goto error;

        adapter->priv_num = 0;

        for (i = 0; i < MWIFIEX_MAX_BSS_NUM; i++) {
                /* Allocate memory for private structure */
                adapter->priv[i] =
                        kzalloc(sizeof(struct mwifiex_private), GFP_KERNEL);
                if (!adapter->priv[i])
                        goto error;

                adapter->priv[i]->adapter = adapter;
                adapter->priv_num++;
        }
        mwifiex_init_lock_list(adapter);

        init_timer(&adapter->cmd_timer);
        adapter->cmd_timer.function = mwifiex_cmd_timeout_func;
        adapter->cmd_timer.data = (unsigned long) adapter;

        return 0;

error:
        dev_dbg(adapter->dev, "info: leave mwifiex_register with error\n");

        for (i = 0; i < adapter->priv_num; i++)
                kfree(adapter->priv[i]);

        kfree(adapter);

        return -1;
}

/*
 * This function unregisters the device and performs all the necessary
 * cleanups.
 *
 * The following cleanup operations are performed -
 *      - Free the timers
 *      - Free beacon buffers
 *      - Free private structures
 *      - Free adapter structure
 */
static int mwifiex_unregister(struct mwifiex_adapter *adapter)
{
        s32 i;

        if (adapter->if_ops.cleanup_if)
                adapter->if_ops.cleanup_if(adapter);

        del_timer_sync(&adapter->cmd_timer);

        /* Free private structures */
        for (i = 0; i < adapter->priv_num; i++) {
                if (adapter->priv[i]) {
                        mwifiex_free_curr_bcn(adapter->priv[i]);
                        kfree(adapter->priv[i]);
                }
        }

        vfree(adapter->chan_stats);
        kfree(adapter);
        return 0;
}

static int mwifiex_process_rx(struct mwifiex_adapter *adapter)
{
        unsigned long flags;
        struct sk_buff *skb;

        spin_lock_irqsave(&adapter->rx_proc_lock, flags);
        if (adapter->rx_processing || adapter->rx_locked) {
                spin_unlock_irqrestore(&adapter->rx_proc_lock, flags);
                goto exit_rx_proc;
        } else {
                adapter->rx_processing = true;
                spin_unlock_irqrestore(&adapter->rx_proc_lock, flags);
        }

        /* Check for Rx data */
        while ((skb = skb_dequeue(&adapter->rx_data_q))) {
                atomic_dec(&adapter->rx_pending);
                if (adapter->delay_main_work &&
                    (atomic_read(&adapter->rx_pending) < LOW_RX_PENDING)) {
                        if (adapter->if_ops.submit_rem_rx_urbs)
                                adapter->if_ops.submit_rem_rx_urbs(adapter);
                        adapter->delay_main_work = false;
                        queue_work(adapter->workqueue, &adapter->main_work);
                }
                mwifiex_handle_rx_packet(adapter, skb);
        }
        spin_lock_irqsave(&adapter->rx_proc_lock, flags);
        adapter->rx_processing = false;
        spin_unlock_irqrestore(&adapter->rx_proc_lock, flags);

exit_rx_proc:
        return 0;
}

/*
 * The main process.
 *
 * This function is the main procedure of the driver and handles various driver
 * operations. It runs in a loop and provides the core functionalities.
 *
 * The main responsibilities of this function are -
 *      - Ensure concurrency control
 *      - Handle pending interrupts and call interrupt handlers
 *      - Wake up the card if required
 *      - Handle command responses and call response handlers
 *      - Handle events and call event handlers
 *      - Execute pending commands
 *      - Transmit pending data packets
 */
int mwifiex_main_process(struct mwifiex_adapter *adapter)
{
        int ret = 0;
        unsigned long flags;

        spin_lock_irqsave(&adapter->main_proc_lock, flags);

        /* Check if already processing */
        if (adapter->mwifiex_processing) {
                spin_unlock_irqrestore(&adapter->main_proc_lock, flags);
                goto exit_main_proc;
        } else {
                adapter->mwifiex_processing = true;
                spin_unlock_irqrestore(&adapter->main_proc_lock, flags);
        }
process_start:
        do {
                if ((adapter->hw_status == MWIFIEX_HW_STATUS_CLOSING) ||
                    (adapter->hw_status == MWIFIEX_HW_STATUS_NOT_READY))
                        break;

                /* If we process interrupts first, it would increase RX pending
                 * even further. Avoid this by checking if rx_pending has
                 * crossed high threshold and schedule rx work queue
                 * and then process interrupts
                 */
                if (atomic_read(&adapter->rx_pending) >= HIGH_RX_PENDING) {
                        adapter->delay_main_work = true;
                        if (!adapter->rx_processing)
                                queue_work(adapter->rx_workqueue,
                                           &adapter->rx_work);
                        break;
                }

                /* Handle pending interrupt if any */
                if (adapter->int_status) {
                        if (adapter->hs_activated)
                                mwifiex_process_hs_config(adapter);
                        if (adapter->if_ops.process_int_status)
                                adapter->if_ops.process_int_status(adapter);
                }

                if (adapter->rx_work_enabled && adapter->data_received)
                        queue_work(adapter->rx_workqueue, &adapter->rx_work);

                /* Need to wake up the card ? */
                if ((adapter->ps_state == PS_STATE_SLEEP) &&
                    (adapter->pm_wakeup_card_req &&
                     !adapter->pm_wakeup_fw_try) &&
                    (is_command_pending(adapter) ||
                     !mwifiex_wmm_lists_empty(adapter))) {
                        adapter->pm_wakeup_fw_try = true;
                        adapter->if_ops.wakeup(adapter);
                        continue;
                }

                if (IS_CARD_RX_RCVD(adapter)) {
                        adapter->data_received = false;
                        adapter->pm_wakeup_fw_try = false;
                        if (adapter->ps_state == PS_STATE_SLEEP)
                                adapter->ps_state = PS_STATE_AWAKE;
                } else {
                        /* We have tried to wakeup the card already */
                        if (adapter->pm_wakeup_fw_try)
                                break;
                        if (adapter->ps_state != PS_STATE_AWAKE ||
                            adapter->tx_lock_flag)
                                break;

                        if ((!adapter->scan_chan_gap_enabled &&
                             adapter->scan_processing) || adapter->data_sent ||
                            mwifiex_wmm_lists_empty(adapter)) {
                                if (adapter->cmd_sent || adapter->curr_cmd ||
                                    (!is_command_pending(adapter)))
                                        break;
                        }
                }

                /* Check for event */
                if (adapter->event_received) {
                        adapter->event_received = false;
                        mwifiex_process_event(adapter);
                }

                /* Check for Cmd Resp */
                if (adapter->cmd_resp_received) {
                        adapter->cmd_resp_received = false;
                        mwifiex_process_cmdresp(adapter);

                        /* call mwifiex back when init_fw is done */
                        if (adapter->hw_status == MWIFIEX_HW_STATUS_INIT_DONE) {
                                adapter->hw_status = MWIFIEX_HW_STATUS_READY;
                                mwifiex_init_fw_complete(adapter);
                        }
                }

                /* Check if we need to confirm Sleep Request
                   received previously */
                if (adapter->ps_state == PS_STATE_PRE_SLEEP) {
                        if (!adapter->cmd_sent && !adapter->curr_cmd)
                                mwifiex_check_ps_cond(adapter);
                }

                /* * The ps_state may have been changed during processing of
                 * Sleep Request event.
                 */
                if ((adapter->ps_state == PS_STATE_SLEEP) ||
                    (adapter->ps_state == PS_STATE_PRE_SLEEP) ||
                    (adapter->ps_state == PS_STATE_SLEEP_CFM) ||
                    adapter->tx_lock_flag)
                        continue;

                if (!adapter->cmd_sent && !adapter->curr_cmd) {
                        if (mwifiex_exec_next_cmd(adapter) == -1) {
                                ret = -1;
                                break;
                        }
                }

                if ((adapter->scan_chan_gap_enabled ||
                     !adapter->scan_processing) &&
                    !adapter->data_sent && !mwifiex_wmm_lists_empty(adapter)) {
                        mwifiex_wmm_process_tx(adapter);
                        if (adapter->hs_activated) {
                                adapter->is_hs_configured = false;
                                mwifiex_hs_activated_event
                                        (mwifiex_get_priv
                                         (adapter, MWIFIEX_BSS_ROLE_ANY),
                                         false);
                        }
                }

                if (adapter->delay_null_pkt && !adapter->cmd_sent &&
                    !adapter->curr_cmd && !is_command_pending(adapter) &&
                    mwifiex_wmm_lists_empty(adapter)) {
                        if (!mwifiex_send_null_packet
                            (mwifiex_get_priv(adapter, MWIFIEX_BSS_ROLE_STA),
                             MWIFIEX_TxPD_POWER_MGMT_NULL_PACKET |
                             MWIFIEX_TxPD_POWER_MGMT_LAST_PACKET)) {
                                adapter->delay_null_pkt = false;
                                adapter->ps_state = PS_STATE_SLEEP;
                        }
                        break;
                }
        } while (true);

        spin_lock_irqsave(&adapter->main_proc_lock, flags);
        if (!adapter->delay_main_work &&
            (adapter->int_status || IS_CARD_RX_RCVD(adapter))) {
                spin_unlock_irqrestore(&adapter->main_proc_lock, flags);
                goto process_start;
        }

        adapter->mwifiex_processing = false;
        spin_unlock_irqrestore(&adapter->main_proc_lock, flags);

exit_main_proc:
        if (adapter->hw_status == MWIFIEX_HW_STATUS_CLOSING)
                mwifiex_shutdown_drv(adapter);
        return ret;
}
EXPORT_SYMBOL_GPL(mwifiex_main_process);

/*
 * This function frees the adapter structure.
 *
 * Additionally, this closes the netlink socket, frees the timers
 * and private structures.
 */
static void mwifiex_free_adapter(struct mwifiex_adapter *adapter)
{
        if (!adapter) {
                pr_err("%s: adapter is NULL\n", __func__);
                return;
        }

        mwifiex_unregister(adapter);
        pr_debug("info: %s: free adapter\n", __func__);
}

/*
 * This function cancels all works in the queue and destroys
 * the main workqueue.
 */
static void mwifiex_terminate_workqueue(struct mwifiex_adapter *adapter)
{
        flush_workqueue(adapter->workqueue);
        destroy_workqueue(adapter->workqueue);
        adapter->workqueue = NULL;

        if (adapter->rx_workqueue) {
                flush_workqueue(adapter->rx_workqueue);
                destroy_workqueue(adapter->rx_workqueue);
                adapter->rx_workqueue = NULL;
        }
}

/*
 * This function gets firmware and initializes it.
 *
 * The main initialization steps followed are -
 *      - Download the correct firmware to card
 *      - Issue the init commands to firmware
 */
static void mwifiex_fw_dpc(const struct firmware *firmware, void *context)
{
        int ret;
        char fmt[64];
        struct mwifiex_private *priv;
        struct mwifiex_adapter *adapter = context;
        struct mwifiex_fw_image fw;
        struct semaphore *sem = adapter->card_sem;
        bool init_failed = false;
        struct wireless_dev *wdev;

        if (!firmware) {
                dev_err(adapter->dev,
                        "Failed to get firmware %s\n", adapter->fw_name);
                goto err_dnld_fw;
        }

        memset(&fw, 0, sizeof(struct mwifiex_fw_image));
        adapter->firmware = firmware;
        fw.fw_buf = (u8 *) adapter->firmware->data;
        fw.fw_len = adapter->firmware->size;

        if (adapter->if_ops.dnld_fw)
                ret = adapter->if_ops.dnld_fw(adapter, &fw);
        else
                ret = mwifiex_dnld_fw(adapter, &fw);
        if (ret == -1)
                goto err_dnld_fw;

        dev_notice(adapter->dev, "WLAN FW is active\n");

        if (cal_data_cfg) {
                if ((request_firmware(&adapter->cal_data, cal_data_cfg,
                                      adapter->dev)) < 0)
                        dev_err(adapter->dev,
                                "Cal data request_firmware() failed\n");
        }

        /* enable host interrupt after fw dnld is successful */
        if (adapter->if_ops.enable_int) {
                if (adapter->if_ops.enable_int(adapter))
                        goto err_dnld_fw;
        }

        adapter->init_wait_q_woken = false;
        ret = mwifiex_init_fw(adapter);
        if (ret == -1) {
                goto err_init_fw;
        } else if (!ret) {
                adapter->hw_status = MWIFIEX_HW_STATUS_READY;
                goto done;
        }
        /* Wait for mwifiex_init to complete */
        wait_event_interruptible(adapter->init_wait_q,
                                 adapter->init_wait_q_woken);
        if (adapter->hw_status != MWIFIEX_HW_STATUS_READY)
                goto err_init_fw;

        priv = adapter->priv[MWIFIEX_BSS_ROLE_STA];
        if (mwifiex_register_cfg80211(adapter)) {
                dev_err(adapter->dev, "cannot register with cfg80211\n");
                goto err_init_fw;
        }

        if (mwifiex_init_channel_scan_gap(adapter)) {
                dev_err(adapter->dev, "could not init channel stats table\n");
                goto err_init_fw;
        }

        rtnl_lock();
        /* Create station interface by default */
        wdev = mwifiex_add_virtual_intf(adapter->wiphy, "mlan%d",
                                        NL80211_IFTYPE_STATION, NULL, NULL);
        if (IS_ERR(wdev)) {
                dev_err(adapter->dev, "cannot create default STA interface\n");
                rtnl_unlock();
                goto err_add_intf;
        }
        rtnl_unlock();

        mwifiex_drv_get_driver_version(adapter, fmt, sizeof(fmt) - 1);
        dev_notice(adapter->dev, "driver_version = %s\n", fmt);
        goto done;

err_add_intf:
        wiphy_unregister(adapter->wiphy);
        wiphy_free(adapter->wiphy);
err_init_fw:
        if (adapter->if_ops.disable_int)
                adapter->if_ops.disable_int(adapter);
err_dnld_fw:
        pr_debug("info: %s: unregister device\n", __func__);
        if (adapter->if_ops.unregister_dev)
                adapter->if_ops.unregister_dev(adapter);

        if ((adapter->hw_status == MWIFIEX_HW_STATUS_FW_READY) ||
            (adapter->hw_status == MWIFIEX_HW_STATUS_READY)) {
                pr_debug("info: %s: shutdown mwifiex\n", __func__);
                adapter->init_wait_q_woken = false;

                if (mwifiex_shutdown_drv(adapter) == -EINPROGRESS)
                        wait_event_interruptible(adapter->init_wait_q,
                                                 adapter->init_wait_q_woken);
        }
        adapter->surprise_removed = true;
        mwifiex_terminate_workqueue(adapter);
        init_failed = true;
done:
        if (adapter->cal_data) {
                release_firmware(adapter->cal_data);
                adapter->cal_data = NULL;
        }
        if (adapter->firmware) {
                release_firmware(adapter->firmware);
                adapter->firmware = NULL;
        }
        if (init_failed)
                mwifiex_free_adapter(adapter);
        up(sem);
        return;
}

/*
 * This function initializes the hardware and gets firmware.
 */
static int mwifiex_init_hw_fw(struct mwifiex_adapter *adapter)
{
        int ret;

        ret = request_firmware_nowait(THIS_MODULE, 1, adapter->fw_name,
                                      adapter->dev, GFP_KERNEL, adapter,
                                      mwifiex_fw_dpc);
        if (ret < 0)
                dev_err(adapter->dev,
                        "request_firmware_nowait() returned error %d\n", ret);
        return ret;
}

/*
 * CFG802.11 network device handler for open.
 *
 * Starts the data queue.
 */
static int
mwifiex_open(struct net_device *dev)
{
        netif_tx_start_all_queues(dev);
        return 0;
}

/*
 * CFG802.11 network device handler for close.
 */
static int
mwifiex_close(struct net_device *dev)
{
        struct mwifiex_private *priv = mwifiex_netdev_get_priv(dev);

        if (priv->scan_request) {
                dev_dbg(priv->adapter->dev, "aborting scan on ndo_stop\n");
                cfg80211_scan_done(priv->scan_request, 1);
                priv->scan_request = NULL;
                priv->scan_aborting = true;
        }

        return 0;
}

/*
 * Add buffer into wmm tx queue and queue work to transmit it.
 */
int mwifiex_queue_tx_pkt(struct mwifiex_private *priv, struct sk_buff *skb)
{
        struct netdev_queue *txq;
        int index = mwifiex_1d_to_wmm_queue[skb->priority];

        if (atomic_inc_return(&priv->wmm_tx_pending[index]) >= MAX_TX_PENDING) {
                txq = netdev_get_tx_queue(priv->netdev, index);
                if (!netif_tx_queue_stopped(txq)) {
                        netif_tx_stop_queue(txq);
                        dev_dbg(priv->adapter->dev, "stop queue: %d\n", index);
                }
        }

        atomic_inc(&priv->adapter->tx_pending);
        mwifiex_wmm_add_buf_txqueue(priv, skb);

        queue_work(priv->adapter->workqueue, &priv->adapter->main_work);

        return 0;
}

/*
 * CFG802.11 network device handler for data transmission.
 */
static int
mwifiex_hard_start_xmit(struct sk_buff *skb, struct net_device *dev)
{
        struct mwifiex_private *priv = mwifiex_netdev_get_priv(dev);
        struct sk_buff *new_skb;
        struct mwifiex_txinfo *tx_info;

        dev_dbg(priv->adapter->dev, "data: %lu BSS(%d-%d): Data <= kernel\n",
                jiffies, priv->bss_type, priv->bss_num);

        if (priv->adapter->surprise_removed) {
                kfree_skb(skb);
                priv->stats.tx_dropped++;
                return 0;
        }
        if (!skb->len || (skb->len > ETH_FRAME_LEN)) {
                dev_err(priv->adapter->dev, "Tx: bad skb len %d\n", skb->len);
                kfree_skb(skb);
                priv->stats.tx_dropped++;
                return 0;
        }
        if (skb_headroom(skb) < MWIFIEX_MIN_DATA_HEADER_LEN) {
                dev_dbg(priv->adapter->dev,
                        "data: Tx: insufficient skb headroom %d\n",
                        skb_headroom(skb));
                /* Insufficient skb headroom - allocate a new skb */
                new_skb =
                        skb_realloc_headroom(skb, MWIFIEX_MIN_DATA_HEADER_LEN);
                if (unlikely(!new_skb)) {
                        dev_err(priv->adapter->dev, "Tx: cannot alloca new_skb\n");
                        kfree_skb(skb);
                        priv->stats.tx_dropped++;
                        return 0;
                }
                kfree_skb(skb);
                skb = new_skb;
                dev_dbg(priv->adapter->dev, "info: new skb headroomd %d\n",
                        skb_headroom(skb));
        }

        tx_info = MWIFIEX_SKB_TXCB(skb);
        memset(tx_info, 0, sizeof(*tx_info));
        tx_info->bss_num = priv->bss_num;
        tx_info->bss_type = priv->bss_type;
        tx_info->pkt_len = skb->len;

        /* Record the current time the packet was queued; used to
         * determine the amount of time the packet was queued in
         * the driver before it was sent to the firmware.
         * The delay is then sent along with the packet to the
         * firmware for aggregate delay calculation for stats and
         * MSDU lifetime expiry.
         */
        __net_timestamp(skb);

        mwifiex_queue_tx_pkt(priv, skb);

        return 0;
}

/*
 * CFG802.11 network device handler for setting MAC address.
 */
static int
mwifiex_set_mac_address(struct net_device *dev, void *addr)
{
        struct mwifiex_private *priv = mwifiex_netdev_get_priv(dev);
        struct sockaddr *hw_addr = addr;
        int ret;

        memcpy(priv->curr_addr, hw_addr->sa_data, ETH_ALEN);

        /* Send request to firmware */
        ret = mwifiex_send_cmd(priv, HostCmd_CMD_802_11_MAC_ADDRESS,
                               HostCmd_ACT_GEN_SET, 0, NULL, true);

        if (!ret)
                memcpy(priv->netdev->dev_addr, priv->curr_addr, ETH_ALEN);
        else
                dev_err(priv->adapter->dev,
                        "set mac address failed: ret=%d\n", ret);

        memcpy(dev->dev_addr, priv->curr_addr, ETH_ALEN);

        return ret;
}

/*
 * CFG802.11 network device handler for setting multicast list.
 */
static void mwifiex_set_multicast_list(struct net_device *dev)
{
        struct mwifiex_private *priv = mwifiex_netdev_get_priv(dev);
        struct mwifiex_multicast_list mcast_list;

        if (dev->flags & IFF_PROMISC) {
                mcast_list.mode = MWIFIEX_PROMISC_MODE;
        } else if (dev->flags & IFF_ALLMULTI ||
                   netdev_mc_count(dev) > MWIFIEX_MAX_MULTICAST_LIST_SIZE) {
                mcast_list.mode = MWIFIEX_ALL_MULTI_MODE;
        } else {
                mcast_list.mode = MWIFIEX_MULTICAST_MODE;
                mcast_list.num_multicast_addr =
                        mwifiex_copy_mcast_addr(&mcast_list, dev);
        }
        mwifiex_request_set_multicast_list(priv, &mcast_list);
}

/*
 * CFG802.11 network device handler for transmission timeout.
 */
static void
mwifiex_tx_timeout(struct net_device *dev)
{
        struct mwifiex_private *priv = mwifiex_netdev_get_priv(dev);

        priv->num_tx_timeout++;
        priv->tx_timeout_cnt++;
        dev_err(priv->adapter->dev,
                "%lu : Tx timeout(#%d), bss_type-num = %d-%d\n",
                jiffies, priv->tx_timeout_cnt, priv->bss_type, priv->bss_num);
        mwifiex_set_trans_start(dev);

        if (priv->tx_timeout_cnt > TX_TIMEOUT_THRESHOLD &&
            priv->adapter->if_ops.card_reset) {
                dev_err(priv->adapter->dev,
                        "tx_timeout_cnt exceeds threshold. Triggering card reset!\n");
                priv->adapter->if_ops.card_reset(priv->adapter);
        }
}

/*
 * CFG802.11 network device handler for statistics retrieval.
 */
static struct net_device_stats *mwifiex_get_stats(struct net_device *dev)
{
        struct mwifiex_private *priv = mwifiex_netdev_get_priv(dev);

        return &priv->stats;
}

static u16
mwifiex_netdev_select_wmm_queue(struct net_device *dev, struct sk_buff *skb,
                                void *accel_priv, select_queue_fallback_t fallback)
{
        skb->priority = cfg80211_classify8021d(skb, NULL);
        return mwifiex_1d_to_wmm_queue[skb->priority];
}

/* Network device handlers */
static const struct net_device_ops mwifiex_netdev_ops = {
        .ndo_open = mwifiex_open,
        .ndo_stop = mwifiex_close,
        .ndo_start_xmit = mwifiex_hard_start_xmit,
        .ndo_set_mac_address = mwifiex_set_mac_address,
        .ndo_tx_timeout = mwifiex_tx_timeout,
        .ndo_get_stats = mwifiex_get_stats,
        .ndo_set_rx_mode = mwifiex_set_multicast_list,
        .ndo_select_queue = mwifiex_netdev_select_wmm_queue,
};

/*
 * This function initializes the private structure parameters.
 *
 * The following wait queues are initialized -
 *      - IOCTL wait queue
 *      - Command wait queue
 *      - Statistics wait queue
 *
 * ...and the following default parameters are set -
 *      - Current key index     : Set to 0
 *      - Rate index            : Set to auto
 *      - Media connected       : Set to disconnected
 *      - Adhoc link sensed     : Set to false
 *      - Nick name             : Set to null
 *      - Number of Tx timeout  : Set to 0
 *      - Device address        : Set to current address
 *
 * In addition, the CFG80211 work queue is also created.
 */
void mwifiex_init_priv_params(struct mwifiex_private *priv,
                                                struct net_device *dev)
{
        dev->netdev_ops = &mwifiex_netdev_ops;
        dev->destructor = free_netdev;
        /* Initialize private structure */
        priv->current_key_index = 0;
        priv->media_connected = false;
        memset(&priv->nick_name, 0, sizeof(priv->nick_name));
        memset(priv->mgmt_ie, 0,
               sizeof(struct mwifiex_ie) * MAX_MGMT_IE_INDEX);
        priv->beacon_idx = MWIFIEX_AUTO_IDX_MASK;
        priv->proberesp_idx = MWIFIEX_AUTO_IDX_MASK;
        priv->assocresp_idx = MWIFIEX_AUTO_IDX_MASK;
        priv->rsn_idx = MWIFIEX_AUTO_IDX_MASK;
        priv->num_tx_timeout = 0;
        memcpy(dev->dev_addr, priv->curr_addr, ETH_ALEN);
}

/*
 * This function check if command is pending.
 */
int is_command_pending(struct mwifiex_adapter *adapter)
{
        unsigned long flags;
        int is_cmd_pend_q_empty;

        spin_lock_irqsave(&adapter->cmd_pending_q_lock, flags);
        is_cmd_pend_q_empty = list_empty(&adapter->cmd_pending_q);
        spin_unlock_irqrestore(&adapter->cmd_pending_q_lock, flags);

        return !is_cmd_pend_q_empty;
}

/*
 * This is the RX work queue function.
 *
 * It handles the RX operations.
 */
static void mwifiex_rx_work_queue(struct work_struct *work)
{
        struct mwifiex_adapter *adapter =
                container_of(work, struct mwifiex_adapter, rx_work);

        if (adapter->surprise_removed)
                return;
        mwifiex_process_rx(adapter);
}

/*
 * This is the main work queue function.
 *
 * It handles the main process, which in turn handles the complete
 * driver operations.
 */
static void mwifiex_main_work_queue(struct work_struct *work)
{
        struct mwifiex_adapter *adapter =
                container_of(work, struct mwifiex_adapter, main_work);

        if (adapter->surprise_removed)
                return;
        mwifiex_main_process(adapter);
}

/*
 * This function adds the card.
 *
 * This function follows the following major steps to set up the device -
 *      - Initialize software. This includes probing the card, registering
 *        the interface operations table, and allocating/initializing the
 *        adapter structure
 *      - Set up the netlink socket
 *      - Create and start the main work queue
 *      - Register the device
 *      - Initialize firmware and hardware
 *      - Add logical interfaces
 */
int
mwifiex_add_card(void *card, struct semaphore *sem,
                 struct mwifiex_if_ops *if_ops, u8 iface_type)
{
        struct mwifiex_adapter *adapter;

        if (down_interruptible(sem))
                goto exit_sem_err;

        if (mwifiex_register(card, if_ops, (void **)&adapter)) {
                pr_err("%s: software init failed\n", __func__);
                goto err_init_sw;
        }

        adapter->iface_type = iface_type;
        adapter->card_sem = sem;

        adapter->hw_status = MWIFIEX_HW_STATUS_INITIALIZING;
        adapter->surprise_removed = false;
        init_waitqueue_head(&adapter->init_wait_q);
        adapter->is_suspended = false;
        adapter->hs_activated = false;
        init_waitqueue_head(&adapter->hs_activate_wait_q);
        init_waitqueue_head(&adapter->cmd_wait_q.wait);
        adapter->cmd_wait_q.status = 0;
        adapter->scan_wait_q_woken = false;

        if ((num_possible_cpus() > 1) || adapter->iface_type == MWIFIEX_USB) {
                adapter->rx_work_enabled = true;
                pr_notice("rx work enabled, cpus %d\n", num_possible_cpus());
        }

        adapter->workqueue =
                alloc_workqueue("MWIFIEX_WORK_QUEUE",
                                WQ_HIGHPRI | WQ_MEM_RECLAIM | WQ_UNBOUND, 1);
        if (!adapter->workqueue)
                goto err_kmalloc;

        INIT_WORK(&adapter->main_work, mwifiex_main_work_queue);

        if (adapter->rx_work_enabled) {
                adapter->rx_workqueue = alloc_workqueue("MWIFIEX_RX_WORK_QUEUE",
                                                        WQ_HIGHPRI |
                                                        WQ_MEM_RECLAIM |
                                                        WQ_UNBOUND, 1);
                if (!adapter->rx_workqueue)
                        goto err_kmalloc;

                INIT_WORK(&adapter->rx_work, mwifiex_rx_work_queue);
        }

        if (adapter->if_ops.iface_work)
                INIT_WORK(&adapter->iface_work, adapter->if_ops.iface_work);

        /* Register the device. Fill up the private data structure with relevant
           information from the card. */
        if (adapter->if_ops.register_dev(adapter)) {
                pr_err("%s: failed to register mwifiex device\n", __func__);
                goto err_registerdev;
        }

        if (mwifiex_init_hw_fw(adapter)) {
                pr_err("%s: firmware init failed\n", __func__);
                goto err_init_fw;
        }

        return 0;

err_init_fw:
        pr_debug("info: %s: unregister device\n", __func__);
        if (adapter->if_ops.unregister_dev)
                adapter->if_ops.unregister_dev(adapter);
        if ((adapter->hw_status == MWIFIEX_HW_STATUS_FW_READY) ||
            (adapter->hw_status == MWIFIEX_HW_STATUS_READY)) {
                pr_debug("info: %s: shutdown mwifiex\n", __func__);
                adapter->init_wait_q_woken = false;

                if (mwifiex_shutdown_drv(adapter) == -EINPROGRESS)
                        wait_event_interruptible(adapter->init_wait_q,
                                                 adapter->init_wait_q_woken);
        }
err_registerdev:
        adapter->surprise_removed = true;
        mwifiex_terminate_workqueue(adapter);
err_kmalloc:
        mwifiex_free_adapter(adapter);

err_init_sw:
        up(sem);

exit_sem_err:
        return -1;
}
EXPORT_SYMBOL_GPL(mwifiex_add_card);

/*
 * This function removes the card.
 *
 * This function follows the following major steps to remove the device -
 *      - Stop data traffic
 *      - Shutdown firmware
 *      - Remove the logical interfaces
 *      - Terminate the work queue
 *      - Unregister the device
 *      - Free the adapter structure
 */
int mwifiex_remove_card(struct mwifiex_adapter *adapter, struct semaphore *sem)
{
        struct mwifiex_private *priv = NULL;
        int i;

        if (down_interruptible(sem))
                goto exit_sem_err;

        if (!adapter)
                goto exit_remove;

        /* We can no longer handle interrupts once we start doing the teardown
         * below. */
        if (adapter->if_ops.disable_int)
                adapter->if_ops.disable_int(adapter);

        adapter->surprise_removed = true;

        /* Stop data */
        for (i = 0; i < adapter->priv_num; i++) {
                priv = adapter->priv[i];
                if (priv && priv->netdev) {
                        mwifiex_stop_net_dev_queue(priv->netdev, adapter);
                        if (netif_carrier_ok(priv->netdev))
                                netif_carrier_off(priv->netdev);
                }
        }

        dev_dbg(adapter->dev, "cmd: calling mwifiex_shutdown_drv...\n");
        adapter->init_wait_q_woken = false;

        if (mwifiex_shutdown_drv(adapter) == -EINPROGRESS)
                wait_event_interruptible(adapter->init_wait_q,
                                         adapter->init_wait_q_woken);
        dev_dbg(adapter->dev, "cmd: mwifiex_shutdown_drv done\n");
        if (atomic_read(&adapter->rx_pending) ||
            atomic_read(&adapter->tx_pending) ||
            atomic_read(&adapter->cmd_pending)) {
                dev_err(adapter->dev, "rx_pending=%d, tx_pending=%d, "
                       "cmd_pending=%d\n",
                       atomic_read(&adapter->rx_pending),
                       atomic_read(&adapter->tx_pending),
                       atomic_read(&adapter->cmd_pending));
        }

        for (i = 0; i < adapter->priv_num; i++) {
                priv = adapter->priv[i];

                if (!priv)
                        continue;

                rtnl_lock();
                if (priv->wdev && priv->netdev)
                        mwifiex_del_virtual_intf(adapter->wiphy, priv->wdev);
                rtnl_unlock();
        }

        wiphy_unregister(adapter->wiphy);
        wiphy_free(adapter->wiphy);

        mwifiex_terminate_workqueue(adapter);

        /* Unregister device */
        dev_dbg(adapter->dev, "info: unregister device\n");
        if (adapter->if_ops.unregister_dev)
                adapter->if_ops.unregister_dev(adapter);
        /* Free adapter structure */
        dev_dbg(adapter->dev, "info: free adapter\n");
        mwifiex_free_adapter(adapter);

exit_remove:
        up(sem);
exit_sem_err:
        return 0;
}
EXPORT_SYMBOL_GPL(mwifiex_remove_card);

/*
 * This function initializes the module.
 *
 * The debug FS is also initialized if configured.
 */
static int
mwifiex_init_module(void)
{
#ifdef CONFIG_DEBUG_FS
        mwifiex_debugfs_init();
#endif
        return 0;
}

/*
 * This function cleans up the module.
 *
 * The debug FS is removed if available.
 */
static void
mwifiex_cleanup_module(void)
{
#ifdef CONFIG_DEBUG_FS
        mwifiex_debugfs_remove();
#endif
}

module_init(mwifiex_init_module);
module_exit(mwifiex_cleanup_module);

MODULE_AUTHOR("Marvell International Ltd.");
MODULE_DESCRIPTION("Marvell WiFi-Ex Driver version " VERSION);
MODULE_VERSION(VERSION);
MODULE_LICENSE("GPL v2");