/*
 * drivers/net/wireless/mwl8k.c
 * Driver for Marvell TOPDOG 802.11 Wireless cards
 *
 * Copyright (C) 2008, 2009, 2010 Marvell Semiconductor Inc.
 *
 * This file is licensed under the terms of the GNU General Public
 * License version 2.  This program is licensed "as is" without any
 * warranty of any kind, whether express or implied.
 */

#include <linux/interrupt.h>
#include <linux/module.h>
#include <linux/kernel.h>
#include <linux/sched.h>
#include <linux/spinlock.h>
#include <linux/list.h>
#include <linux/pci.h>
#include <linux/delay.h>
#include <linux/completion.h>
#include <linux/etherdevice.h>
#include <linux/slab.h>
#include <net/mac80211.h>
#include <linux/moduleparam.h>
#include <linux/firmware.h>
#include <linux/workqueue.h>

#define MWL8K_DESC      "Marvell TOPDOG(R) 802.11 Wireless Network Driver"
#define MWL8K_NAME      KBUILD_MODNAME
#define MWL8K_VERSION   "0.13"

/* Module parameters */
static bool ap_mode_default;
module_param(ap_mode_default, bool, 0);
MODULE_PARM_DESC(ap_mode_default,
                 "Set to 1 to make ap mode the default instead of sta mode");

/* Register definitions */
#define MWL8K_HIU_GEN_PTR                       0x00000c10
#define  MWL8K_MODE_STA                          0x0000005a
#define  MWL8K_MODE_AP                           0x000000a5
#define MWL8K_HIU_INT_CODE                      0x00000c14
#define  MWL8K_FWSTA_READY                       0xf0f1f2f4
#define  MWL8K_FWAP_READY                        0xf1f2f4a5
#define  MWL8K_INT_CODE_CMD_FINISHED             0x00000005
#define MWL8K_HIU_SCRATCH                       0x00000c40

/* Host->device communications */
#define MWL8K_HIU_H2A_INTERRUPT_EVENTS          0x00000c18
#define MWL8K_HIU_H2A_INTERRUPT_STATUS          0x00000c1c
#define MWL8K_HIU_H2A_INTERRUPT_MASK            0x00000c20
#define MWL8K_HIU_H2A_INTERRUPT_CLEAR_SEL       0x00000c24
#define MWL8K_HIU_H2A_INTERRUPT_STATUS_MASK     0x00000c28
#define  MWL8K_H2A_INT_DUMMY                     (1 << 20)
#define  MWL8K_H2A_INT_RESET                     (1 << 15)
#define  MWL8K_H2A_INT_DOORBELL                  (1 << 1)
#define  MWL8K_H2A_INT_PPA_READY                 (1 << 0)

/* Device->host communications */
#define MWL8K_HIU_A2H_INTERRUPT_EVENTS          0x00000c2c
#define MWL8K_HIU_A2H_INTERRUPT_STATUS          0x00000c30
#define MWL8K_HIU_A2H_INTERRUPT_MASK            0x00000c34
#define MWL8K_HIU_A2H_INTERRUPT_CLEAR_SEL       0x00000c38
#define MWL8K_HIU_A2H_INTERRUPT_STATUS_MASK     0x00000c3c
#define  MWL8K_A2H_INT_DUMMY                     (1 << 20)
#define  MWL8K_A2H_INT_BA_WATCHDOG               (1 << 14)
#define  MWL8K_A2H_INT_CHNL_SWITCHED             (1 << 11)
#define  MWL8K_A2H_INT_QUEUE_EMPTY               (1 << 10)
#define  MWL8K_A2H_INT_RADAR_DETECT              (1 << 7)
#define  MWL8K_A2H_INT_RADIO_ON                  (1 << 6)
#define  MWL8K_A2H_INT_RADIO_OFF                 (1 << 5)
#define  MWL8K_A2H_INT_MAC_EVENT                 (1 << 3)
#define  MWL8K_A2H_INT_OPC_DONE                  (1 << 2)
#define  MWL8K_A2H_INT_RX_READY                  (1 << 1)
#define  MWL8K_A2H_INT_TX_DONE                   (1 << 0)

/* HW micro second timer register
 * located at offset 0xA600. This
 * will be used to timestamp tx
 * packets.
 */

#define MWL8K_HW_TIMER_REGISTER                 0x0000a600
#define BBU_RXRDY_CNT_REG                       0x0000a860
#define NOK_CCA_CNT_REG                         0x0000a6a0
#define BBU_AVG_NOISE_VAL                       0x67

#define MWL8K_A2H_EVENTS        (MWL8K_A2H_INT_DUMMY | \
                                 MWL8K_A2H_INT_CHNL_SWITCHED | \
                                 MWL8K_A2H_INT_QUEUE_EMPTY | \
                                 MWL8K_A2H_INT_RADAR_DETECT | \
                                 MWL8K_A2H_INT_RADIO_ON | \
                                 MWL8K_A2H_INT_RADIO_OFF | \
                                 MWL8K_A2H_INT_MAC_EVENT | \
                                 MWL8K_A2H_INT_OPC_DONE | \
                                 MWL8K_A2H_INT_RX_READY | \
                                 MWL8K_A2H_INT_TX_DONE | \
                                 MWL8K_A2H_INT_BA_WATCHDOG)

#define MWL8K_RX_QUEUES         1
#define MWL8K_TX_WMM_QUEUES     4
#define MWL8K_MAX_AMPDU_QUEUES  8
#define MWL8K_MAX_TX_QUEUES     (MWL8K_TX_WMM_QUEUES + MWL8K_MAX_AMPDU_QUEUES)
#define mwl8k_tx_queues(priv)   (MWL8K_TX_WMM_QUEUES + (priv)->num_ampdu_queues)

/* txpriorities are mapped with hw queues.
 * Each hw queue has a txpriority.
 */
#define TOTAL_HW_TX_QUEUES      8

/* Each HW queue can have one AMPDU stream.
 * But, because one of the hw queue is reserved,
 * maximum AMPDU queues that can be created are
 * one short of total tx queues.
 */
#define MWL8K_NUM_AMPDU_STREAMS (TOTAL_HW_TX_QUEUES - 1)

#define MWL8K_NUM_CHANS 18

struct rxd_ops {
        int rxd_size;
        void (*rxd_init)(void *rxd, dma_addr_t next_dma_addr);
        void (*rxd_refill)(void *rxd, dma_addr_t addr, int len);
        int (*rxd_process)(void *rxd, struct ieee80211_rx_status *status,
                           __le16 *qos, s8 *noise);
};

struct mwl8k_device_info {
        char *part_name;
        char *helper_image;
        char *fw_image_sta;
        char *fw_image_ap;
        struct rxd_ops *ap_rxd_ops;
        u32 fw_api_ap;
};

struct mwl8k_rx_queue {
        int rxd_count;

        /* hw receives here */
        int head;

        /* refill descs here */
        int tail;

        void *rxd;
        dma_addr_t rxd_dma;
        struct {
                struct sk_buff *skb;
                DEFINE_DMA_UNMAP_ADDR(dma);
        } *buf;
};

struct mwl8k_tx_queue {
        /* hw transmits here */
        int head;

        /* sw appends here */
        int tail;

        unsigned int len;
        struct mwl8k_tx_desc *txd;
        dma_addr_t txd_dma;
        struct sk_buff **skb;
};

enum {
        AMPDU_NO_STREAM,
        AMPDU_STREAM_NEW,
        AMPDU_STREAM_IN_PROGRESS,
        AMPDU_STREAM_ACTIVE,
};

struct mwl8k_ampdu_stream {
        struct ieee80211_sta *sta;
        u8 tid;
        u8 state;
        u8 idx;
};

struct mwl8k_priv {
        struct ieee80211_hw *hw;
        struct pci_dev *pdev;
        int irq;

        struct mwl8k_device_info *device_info;

        void __iomem *sram;
        void __iomem *regs;

        /* firmware */
        const struct firmware *fw_helper;
        const struct firmware *fw_ucode;

        /* hardware/firmware parameters */
        bool ap_fw;
        struct rxd_ops *rxd_ops;
        struct ieee80211_supported_band band_24;
        struct ieee80211_channel channels_24[14];
        struct ieee80211_rate rates_24[13];
        struct ieee80211_supported_band band_50;
        struct ieee80211_channel channels_50[9];
        struct ieee80211_rate rates_50[8];
        u32 ap_macids_supported;
        u32 sta_macids_supported;

        /* Ampdu stream information */
        u8 num_ampdu_queues;
        spinlock_t stream_lock;
        struct mwl8k_ampdu_stream ampdu[MWL8K_MAX_AMPDU_QUEUES];
        struct work_struct watchdog_ba_handle;

        /* firmware access */
        struct mutex fw_mutex;
        struct task_struct *fw_mutex_owner;
        struct task_struct *hw_restart_owner;
        int fw_mutex_depth;
        struct completion *hostcmd_wait;

        atomic_t watchdog_event_pending;

        /* lock held over TX and TX reap */
        spinlock_t tx_lock;

        /* TX quiesce completion, protected by fw_mutex and tx_lock */
        struct completion *tx_wait;

        /* List of interfaces.  */
        u32 macids_used;
        struct list_head vif_list;

        /* power management status cookie from firmware */
        u32 *cookie;
        dma_addr_t cookie_dma;

        u16 num_mcaddrs;
        u8 hw_rev;
        u32 fw_rev;
        u32 caps;

        /*
         * Running count of TX packets in flight, to avoid
         * iterating over the transmit rings each time.
         */
        int pending_tx_pkts;

        struct mwl8k_rx_queue rxq[MWL8K_RX_QUEUES];
        struct mwl8k_tx_queue txq[MWL8K_MAX_TX_QUEUES];
        u32 txq_offset[MWL8K_MAX_TX_QUEUES];

        bool radio_on;
        bool radio_short_preamble;
        bool sniffer_enabled;
        bool wmm_enabled;

        /* XXX need to convert this to handle multiple interfaces */
        bool capture_beacon;
        u8 capture_bssid[ETH_ALEN];
        struct sk_buff *beacon_skb;

        /*
         * This FJ worker has to be global as it is scheduled from the
         * RX handler.  At this point we don't know which interface it
         * belongs to until the list of bssids waiting to complete join
         * is checked.
         */
        struct work_struct finalize_join_worker;

        /* Tasklet to perform TX reclaim.  */
        struct tasklet_struct poll_tx_task;

        /* Tasklet to perform RX.  */
        struct tasklet_struct poll_rx_task;

        /* Most recently reported noise in dBm */
        s8 noise;

        /*
         * preserve the queue configurations so they can be restored if/when
         * the firmware image is swapped.
         */
        struct ieee80211_tx_queue_params wmm_params[MWL8K_TX_WMM_QUEUES];

        /* To perform the task of reloading the firmware */
        struct work_struct fw_reload;
        bool hw_restart_in_progress;

        /* async firmware loading state */
        unsigned fw_state;
        char *fw_pref;
        char *fw_alt;
        bool is_8764;
        struct completion firmware_loading_complete;

        /* bitmap of running BSSes */
        u32 running_bsses;

        /* ACS related */
        bool sw_scan_start;
        struct ieee80211_channel *acs_chan;
        unsigned long channel_time;
        struct survey_info survey[MWL8K_NUM_CHANS];
};

#define MAX_WEP_KEY_LEN         13
#define NUM_WEP_KEYS            4

/* Per interface specific private data */
struct mwl8k_vif {
        struct list_head list;
        struct ieee80211_vif *vif;

        /* Firmware macid for this vif.  */
        int macid;

        /* Non AMPDU sequence number assigned by driver.  */
        u16 seqno;

        /* Saved WEP keys */
        struct {
                u8 enabled;
                u8 key[sizeof(struct ieee80211_key_conf) + MAX_WEP_KEY_LEN];
        } wep_key_conf[NUM_WEP_KEYS];

        /* BSSID */
        u8 bssid[ETH_ALEN];

        /* A flag to indicate is HW crypto is enabled for this bssid */
        bool is_hw_crypto_enabled;
};
#define MWL8K_VIF(_vif) ((struct mwl8k_vif *)&((_vif)->drv_priv))
#define IEEE80211_KEY_CONF(_u8) ((struct ieee80211_key_conf *)(_u8))

struct tx_traffic_info {
        u32 start_time;
        u32 pkts;
};

#define MWL8K_MAX_TID 8
struct mwl8k_sta {
        /* Index into station database. Returned by UPDATE_STADB.  */
        u8 peer_id;
        u8 is_ampdu_allowed;
        struct tx_traffic_info tx_stats[MWL8K_MAX_TID];
};
#define MWL8K_STA(_sta) ((struct mwl8k_sta *)&((_sta)->drv_priv))

static const struct ieee80211_channel mwl8k_channels_24[] = {
        { .band = NL80211_BAND_2GHZ, .center_freq = 2412, .hw_value = 1, },
        { .band = NL80211_BAND_2GHZ, .center_freq = 2417, .hw_value = 2, },
        { .band = NL80211_BAND_2GHZ, .center_freq = 2422, .hw_value = 3, },
        { .band = NL80211_BAND_2GHZ, .center_freq = 2427, .hw_value = 4, },
        { .band = NL80211_BAND_2GHZ, .center_freq = 2432, .hw_value = 5, },
        { .band = NL80211_BAND_2GHZ, .center_freq = 2437, .hw_value = 6, },
        { .band = NL80211_BAND_2GHZ, .center_freq = 2442, .hw_value = 7, },
        { .band = NL80211_BAND_2GHZ, .center_freq = 2447, .hw_value = 8, },
        { .band = NL80211_BAND_2GHZ, .center_freq = 2452, .hw_value = 9, },
        { .band = NL80211_BAND_2GHZ, .center_freq = 2457, .hw_value = 10, },
        { .band = NL80211_BAND_2GHZ, .center_freq = 2462, .hw_value = 11, },
        { .band = NL80211_BAND_2GHZ, .center_freq = 2467, .hw_value = 12, },
        { .band = NL80211_BAND_2GHZ, .center_freq = 2472, .hw_value = 13, },
        { .band = NL80211_BAND_2GHZ, .center_freq = 2484, .hw_value = 14, },
};

static const struct ieee80211_rate mwl8k_rates_24[] = {
        { .bitrate = 10, .hw_value = 2, },
        { .bitrate = 20, .hw_value = 4, },
        { .bitrate = 55, .hw_value = 11, },
        { .bitrate = 110, .hw_value = 22, },
        { .bitrate = 220, .hw_value = 44, },
        { .bitrate = 60, .hw_value = 12, },
        { .bitrate = 90, .hw_value = 18, },
        { .bitrate = 120, .hw_value = 24, },
        { .bitrate = 180, .hw_value = 36, },
        { .bitrate = 240, .hw_value = 48, },
        { .bitrate = 360, .hw_value = 72, },
        { .bitrate = 480, .hw_value = 96, },
        { .bitrate = 540, .hw_value = 108, },
};

static const struct ieee80211_channel mwl8k_channels_50[] = {
        { .band = NL80211_BAND_5GHZ, .center_freq = 5180, .hw_value = 36, },
        { .band = NL80211_BAND_5GHZ, .center_freq = 5200, .hw_value = 40, },
        { .band = NL80211_BAND_5GHZ, .center_freq = 5220, .hw_value = 44, },
        { .band = NL80211_BAND_5GHZ, .center_freq = 5240, .hw_value = 48, },
        { .band = NL80211_BAND_5GHZ, .center_freq = 5745, .hw_value = 149, },
        { .band = NL80211_BAND_5GHZ, .center_freq = 5765, .hw_value = 153, },
        { .band = NL80211_BAND_5GHZ, .center_freq = 5785, .hw_value = 157, },
        { .band = NL80211_BAND_5GHZ, .center_freq = 5805, .hw_value = 161, },
        { .band = NL80211_BAND_5GHZ, .center_freq = 5825, .hw_value = 165, },
};

static const struct ieee80211_rate mwl8k_rates_50[] = {
        { .bitrate = 60, .hw_value = 12, },
        { .bitrate = 90, .hw_value = 18, },
        { .bitrate = 120, .hw_value = 24, },
        { .bitrate = 180, .hw_value = 36, },
        { .bitrate = 240, .hw_value = 48, },
        { .bitrate = 360, .hw_value = 72, },
        { .bitrate = 480, .hw_value = 96, },
        { .bitrate = 540, .hw_value = 108, },
};

/* Set or get info from Firmware */
#define MWL8K_CMD_GET                   0x0000
#define MWL8K_CMD_SET                   0x0001
#define MWL8K_CMD_SET_LIST              0x0002

/* Firmware command codes */
#define MWL8K_CMD_CODE_DNLD             0x0001
#define MWL8K_CMD_GET_HW_SPEC           0x0003
#define MWL8K_CMD_SET_HW_SPEC           0x0004
#define MWL8K_CMD_MAC_MULTICAST_ADR     0x0010
#define MWL8K_CMD_GET_STAT              0x0014
#define MWL8K_CMD_BBP_REG_ACCESS        0x001a
#define MWL8K_CMD_RADIO_CONTROL         0x001c
#define MWL8K_CMD_RF_TX_POWER           0x001e
#define MWL8K_CMD_TX_POWER              0x001f
#define MWL8K_CMD_RF_ANTENNA            0x0020
#define MWL8K_CMD_SET_BEACON            0x0100          /* per-vif */
#define MWL8K_CMD_SET_PRE_SCAN          0x0107
#define MWL8K_CMD_SET_POST_SCAN         0x0108
#define MWL8K_CMD_SET_RF_CHANNEL        0x010a
#define MWL8K_CMD_SET_AID               0x010d
#define MWL8K_CMD_SET_RATE              0x0110
#define MWL8K_CMD_SET_FINALIZE_JOIN     0x0111
#define MWL8K_CMD_RTS_THRESHOLD         0x0113
#define MWL8K_CMD_SET_SLOT              0x0114
#define MWL8K_CMD_SET_EDCA_PARAMS       0x0115
#define MWL8K_CMD_SET_WMM_MODE          0x0123
#define MWL8K_CMD_MIMO_CONFIG           0x0125
#define MWL8K_CMD_USE_FIXED_RATE        0x0126
#define MWL8K_CMD_ENABLE_SNIFFER        0x0150
#define MWL8K_CMD_SET_MAC_ADDR          0x0202          /* per-vif */
#define MWL8K_CMD_SET_RATEADAPT_MODE    0x0203
#define MWL8K_CMD_GET_WATCHDOG_BITMAP   0x0205
#define MWL8K_CMD_DEL_MAC_ADDR          0x0206          /* per-vif */
#define MWL8K_CMD_BSS_START             0x1100          /* per-vif */
#define MWL8K_CMD_SET_NEW_STN           0x1111          /* per-vif */
#define MWL8K_CMD_UPDATE_ENCRYPTION     0x1122          /* per-vif */
#define MWL8K_CMD_UPDATE_STADB          0x1123
#define MWL8K_CMD_BASTREAM              0x1125

#define MWL8K_LEGACY_5G_RATE_OFFSET \
        (ARRAY_SIZE(mwl8k_rates_24) - ARRAY_SIZE(mwl8k_rates_50))

static const char *mwl8k_cmd_name(__le16 cmd, char *buf, int bufsize)
{
        u16 command = le16_to_cpu(cmd);

#define MWL8K_CMDNAME(x)        case MWL8K_CMD_##x: do {\
                                        snprintf(buf, bufsize, "%s", #x);\
                                        return buf;\
                                        } while (0)
        switch (command & ~0x8000) {
                MWL8K_CMDNAME(CODE_DNLD);
                MWL8K_CMDNAME(GET_HW_SPEC);
                MWL8K_CMDNAME(SET_HW_SPEC);
                MWL8K_CMDNAME(MAC_MULTICAST_ADR);
                MWL8K_CMDNAME(GET_STAT);
                MWL8K_CMDNAME(RADIO_CONTROL);
                MWL8K_CMDNAME(RF_TX_POWER);
                MWL8K_CMDNAME(TX_POWER);
                MWL8K_CMDNAME(RF_ANTENNA);
                MWL8K_CMDNAME(SET_BEACON);
                MWL8K_CMDNAME(SET_PRE_SCAN);
                MWL8K_CMDNAME(SET_POST_SCAN);
                MWL8K_CMDNAME(SET_RF_CHANNEL);
                MWL8K_CMDNAME(SET_AID);
                MWL8K_CMDNAME(SET_RATE);
                MWL8K_CMDNAME(SET_FINALIZE_JOIN);
                MWL8K_CMDNAME(RTS_THRESHOLD);
                MWL8K_CMDNAME(SET_SLOT);
                MWL8K_CMDNAME(SET_EDCA_PARAMS);
                MWL8K_CMDNAME(SET_WMM_MODE);
                MWL8K_CMDNAME(MIMO_CONFIG);
                MWL8K_CMDNAME(USE_FIXED_RATE);
                MWL8K_CMDNAME(ENABLE_SNIFFER);
                MWL8K_CMDNAME(SET_MAC_ADDR);
                MWL8K_CMDNAME(SET_RATEADAPT_MODE);
                MWL8K_CMDNAME(BSS_START);
                MWL8K_CMDNAME(SET_NEW_STN);
                MWL8K_CMDNAME(UPDATE_ENCRYPTION);
                MWL8K_CMDNAME(UPDATE_STADB);
                MWL8K_CMDNAME(BASTREAM);
                MWL8K_CMDNAME(GET_WATCHDOG_BITMAP);
        default:
                snprintf(buf, bufsize, "0x%x", cmd);
        }
#undef MWL8K_CMDNAME

        return buf;
}

/* Hardware and firmware reset */
static void mwl8k_hw_reset(struct mwl8k_priv *priv)
{
        iowrite32(MWL8K_H2A_INT_RESET,
                priv->regs + MWL8K_HIU_H2A_INTERRUPT_EVENTS);
        iowrite32(MWL8K_H2A_INT_RESET,
                priv->regs + MWL8K_HIU_H2A_INTERRUPT_EVENTS);
        msleep(20);
}

/* Release fw image */
static void mwl8k_release_fw(const struct firmware **fw)
{
        if (*fw == NULL)
                return;
        release_firmware(*fw);
        *fw = NULL;
}

static void mwl8k_release_firmware(struct mwl8k_priv *priv)
{
        mwl8k_release_fw(&priv->fw_ucode);
        mwl8k_release_fw(&priv->fw_helper);
}

/* states for asynchronous f/w loading */
static void mwl8k_fw_state_machine(const struct firmware *fw, void *context);
enum {
        FW_STATE_INIT = 0,
        FW_STATE_LOADING_PREF,
        FW_STATE_LOADING_ALT,
        FW_STATE_ERROR,
};

/* Request fw image */
static int mwl8k_request_fw(struct mwl8k_priv *priv,
                            const char *fname, const struct firmware **fw,
                            bool nowait)
{
        /* release current image */
        if (*fw != NULL)
                mwl8k_release_fw(fw);

        if (nowait)
                return request_firmware_nowait(THIS_MODULE, 1, fname,
                                               &priv->pdev->dev, GFP_KERNEL,
                                               priv, mwl8k_fw_state_machine);
        else
                return request_firmware(fw, fname, &priv->pdev->dev);
}

static int mwl8k_request_firmware(struct mwl8k_priv *priv, char *fw_image,
                                  bool nowait)
{
        struct mwl8k_device_info *di = priv->device_info;
        int rc;

        if (di->helper_image != NULL) {
                if (nowait)
                        rc = mwl8k_request_fw(priv, di->helper_image,
                                              &priv->fw_helper, true);
                else
                        rc = mwl8k_request_fw(priv, di->helper_image,
                                              &priv->fw_helper, false);
                if (rc)
                        printk(KERN_ERR "%s: Error requesting helper fw %s\n",
                               pci_name(priv->pdev), di->helper_image);

                if (rc || nowait)
                        return rc;
        }

        if (nowait) {
                /*
                 * if we get here, no helper image is needed.  Skip the
                 * FW_STATE_INIT state.
                 */
                priv->fw_state = FW_STATE_LOADING_PREF;
                rc = mwl8k_request_fw(priv, fw_image,
                                      &priv->fw_ucode,
                                      true);
        } else
                rc = mwl8k_request_fw(priv, fw_image,
                                      &priv->fw_ucode, false);
        if (rc) {
                printk(KERN_ERR "%s: Error requesting firmware file %s\n",
                       pci_name(priv->pdev), fw_image);
                mwl8k_release_fw(&priv->fw_helper);
                return rc;
        }

        return 0;
}

struct mwl8k_cmd_pkt {
        __le16  code;
        __le16  length;
        __u8    seq_num;
        __u8    macid;
        __le16  result;
        char    payload[];
} __packed;

/*
 * Firmware loading.
 */
static int
mwl8k_send_fw_load_cmd(struct mwl8k_priv *priv, void *data, int length)
{
        void __iomem *regs = priv->regs;
        dma_addr_t dma_addr;
        int loops;

        dma_addr = dma_map_single(&priv->pdev->dev, data, length,
                                  DMA_TO_DEVICE);
        if (dma_mapping_error(&priv->pdev->dev, dma_addr))
                return -ENOMEM;

        iowrite32(dma_addr, regs + MWL8K_HIU_GEN_PTR);
        iowrite32(0, regs + MWL8K_HIU_INT_CODE);
        iowrite32(MWL8K_H2A_INT_DOORBELL,
                regs + MWL8K_HIU_H2A_INTERRUPT_EVENTS);
        iowrite32(MWL8K_H2A_INT_DUMMY,
                regs + MWL8K_HIU_H2A_INTERRUPT_EVENTS);

        loops = 1000;
        do {
                u32 int_code;
                if (priv->is_8764) {
                        int_code = ioread32(regs +
                                            MWL8K_HIU_H2A_INTERRUPT_STATUS);
                        if (int_code == 0)
                                break;
                } else {
                        int_code = ioread32(regs + MWL8K_HIU_INT_CODE);
                        if (int_code == MWL8K_INT_CODE_CMD_FINISHED) {
                                iowrite32(0, regs + MWL8K_HIU_INT_CODE);
                                break;
                        }
                }
                cond_resched();
                udelay(1);
        } while (--loops);

        dma_unmap_single(&priv->pdev->dev, dma_addr, length, DMA_TO_DEVICE);

        return loops ? 0 : -ETIMEDOUT;
}

static int mwl8k_load_fw_image(struct mwl8k_priv *priv,
                                const u8 *data, size_t length)
{
        struct mwl8k_cmd_pkt *cmd;
        int done;
        int rc = 0;

        cmd = kmalloc(sizeof(*cmd) + 256, GFP_KERNEL);
        if (cmd == NULL)
                return -ENOMEM;

        cmd->code = cpu_to_le16(MWL8K_CMD_CODE_DNLD);
        cmd->seq_num = 0;
        cmd->macid = 0;
        cmd->result = 0;

        done = 0;
        while (length) {
                int block_size = length > 256 ? 256 : length;

                memcpy(cmd->payload, data + done, block_size);
                cmd->length = cpu_to_le16(block_size);

                rc = mwl8k_send_fw_load_cmd(priv, cmd,
                                                sizeof(*cmd) + block_size);
                if (rc)
                        break;

                done += block_size;
                length -= block_size;
        }

        if (!rc) {
                cmd->length = 0;
                rc = mwl8k_send_fw_load_cmd(priv, cmd, sizeof(*cmd));
        }

        kfree(cmd);

        return rc;
}

static int mwl8k_feed_fw_image(struct mwl8k_priv *priv,
                                const u8 *data, size_t length)
{
        unsigned char *buffer;
        int may_continue, rc = 0;
        u32 done, prev_block_size;

        buffer = kmalloc(1024, GFP_KERNEL);
        if (buffer == NULL)
                return -ENOMEM;

        done = 0;
        prev_block_size = 0;
        may_continue = 1000;
        while (may_continue > 0) {
                u32 block_size;

                block_size = ioread32(priv->regs + MWL8K_HIU_SCRATCH);
                if (block_size & 1) {
                        block_size &= ~1;
                        may_continue--;
                } else {
                        done += prev_block_size;
                        length -= prev_block_size;
                }

                if (block_size > 1024 || block_size > length) {
                        rc = -EOVERFLOW;
                        break;
                }

                if (length == 0) {
                        rc = 0;
                        break;
                }

                if (block_size == 0) {
                        rc = -EPROTO;
                        may_continue--;
                        udelay(1);
                        continue;
                }

                prev_block_size = block_size;
                memcpy(buffer, data + done, block_size);

                rc = mwl8k_send_fw_load_cmd(priv, buffer, block_size);
                if (rc)
                        break;
        }

        if (!rc && length != 0)
                rc = -EREMOTEIO;

        kfree(buffer);

        return rc;
}

static int mwl8k_load_firmware(struct ieee80211_hw *hw)
{
        struct mwl8k_priv *priv = hw->priv;
        const struct firmware *fw = priv->fw_ucode;
        int rc;
        int loops;

        if (!memcmp(fw->data, "\x01\x00\x00\x00", 4) && !priv->is_8764) {
                const struct firmware *helper = priv->fw_helper;

                if (helper == NULL) {
                        printk(KERN_ERR "%s: helper image needed but none "
                               "given\n", pci_name(priv->pdev));
                        return -EINVAL;
                }

                rc = mwl8k_load_fw_image(priv, helper->data, helper->size);
                if (rc) {
                        printk(KERN_ERR "%s: unable to load firmware "
                               "helper image\n", pci_name(priv->pdev));
                        return rc;
                }
                msleep(20);

                rc = mwl8k_feed_fw_image(priv, fw->data, fw->size);
        } else {
                if (priv->is_8764)
                        rc = mwl8k_feed_fw_image(priv, fw->data, fw->size);
                else
                        rc = mwl8k_load_fw_image(priv, fw->data, fw->size);
        }

        if (rc) {
                printk(KERN_ERR "%s: unable to load firmware image\n",
                       pci_name(priv->pdev));
                return rc;
        }

        iowrite32(MWL8K_MODE_STA, priv->regs + MWL8K_HIU_GEN_PTR);

        loops = 500000;
        do {
                u32 ready_code;

                ready_code = ioread32(priv->regs + MWL8K_HIU_INT_CODE);
                if (ready_code == MWL8K_FWAP_READY) {
                        priv->ap_fw = true;
                        break;
                } else if (ready_code == MWL8K_FWSTA_READY) {
                        priv->ap_fw = false;
                        break;
                }

                cond_resched();
                udelay(1);
        } while (--loops);

        return loops ? 0 : -ETIMEDOUT;
}


/* DMA header used by firmware and hardware.  */
struct mwl8k_dma_data {
        __le16 fwlen;
        struct ieee80211_hdr wh;
        char data[];
} __packed __aligned(2);

/* Routines to add/remove DMA header from skb.  */
static inline void mwl8k_remove_dma_header(struct sk_buff *skb, __le16 qos)
{
        struct mwl8k_dma_data *tr;
        int hdrlen;

        tr = (struct mwl8k_dma_data *)skb->data;
        hdrlen = ieee80211_hdrlen(tr->wh.frame_control);

        if (hdrlen != sizeof(tr->wh)) {
                if (ieee80211_is_data_qos(tr->wh.frame_control)) {
                        memmove(tr->data - hdrlen, &tr->wh, hdrlen - 2);
                        *((__le16 *)(tr->data - 2)) = qos;
                } else {
                        memmove(tr->data - hdrlen, &tr->wh, hdrlen);
                }
        }

        if (hdrlen != sizeof(*tr))
                skb_pull(skb, sizeof(*tr) - hdrlen);
}

#define REDUCED_TX_HEADROOM     8

static void
mwl8k_add_dma_header(struct mwl8k_priv *priv, struct sk_buff *skb,
                                                int head_pad, int tail_pad)
{
        struct ieee80211_hdr *wh;
        int hdrlen;
        int reqd_hdrlen;
        struct mwl8k_dma_data *tr;

        /*
         * Add a firmware DMA header; the firmware requires that we
         * present a 2-byte payload length followed by a 4-address
         * header (without QoS field), followed (optionally) by any
         * WEP/ExtIV header (but only filled in for CCMP).
         */
        wh = (struct ieee80211_hdr *)skb->data;

        hdrlen = ieee80211_hdrlen(wh->frame_control);

        /*
         * Check if skb_resize is required because of
         * tx_headroom adjustment.
         */
        if (priv->ap_fw && (hdrlen < (sizeof(struct ieee80211_cts)
                                                + REDUCED_TX_HEADROOM))) {
                if (pskb_expand_head(skb, REDUCED_TX_HEADROOM, 0, GFP_ATOMIC)) {

                        wiphy_err(priv->hw->wiphy,
                                        "Failed to reallocate TX buffer\n");
                        return;
                }
                skb->truesize += REDUCED_TX_HEADROOM;
        }

        reqd_hdrlen = sizeof(*tr) + head_pad;

        if (hdrlen != reqd_hdrlen)
                skb_push(skb, reqd_hdrlen - hdrlen);

        if (ieee80211_is_data_qos(wh->frame_control))
                hdrlen -= IEEE80211_QOS_CTL_LEN;

        tr = (struct mwl8k_dma_data *)skb->data;
        if (wh != &tr->wh)
                memmove(&tr->wh, wh, hdrlen);
        if (hdrlen != sizeof(tr->wh))
                memset(((void *)&tr->wh) + hdrlen, 0, sizeof(tr->wh) - hdrlen);

        /*
         * Firmware length is the length of the fully formed "802.11
         * payload".  That is, everything except for the 802.11 header.
         * This includes all crypto material including the MIC.
         */
        tr->fwlen = cpu_to_le16(skb->len - sizeof(*tr) + tail_pad);
}

static void mwl8k_encapsulate_tx_frame(struct mwl8k_priv *priv,
                struct sk_buff *skb)
{
        struct ieee80211_hdr *wh;
        struct ieee80211_tx_info *tx_info;
        struct ieee80211_key_conf *key_conf;
        int data_pad;
        int head_pad = 0;

        wh = (struct ieee80211_hdr *)skb->data;

        tx_info = IEEE80211_SKB_CB(skb);

        key_conf = NULL;
        if (ieee80211_is_data(wh->frame_control))
                key_conf = tx_info->control.hw_key;

        /*
         * Make sure the packet header is in the DMA header format (4-address
         * without QoS), and add head & tail padding when HW crypto is enabled.
         *
         * We have the following trailer padding requirements:
         * - WEP: 4 trailer bytes (ICV)
         * - TKIP: 12 trailer bytes (8 MIC + 4 ICV)
         * - CCMP: 8 trailer bytes (MIC)
         */
        data_pad = 0;
        if (key_conf != NULL) {
                head_pad = key_conf->iv_len;
                switch (key_conf->cipher) {
                case WLAN_CIPHER_SUITE_WEP40:
                case WLAN_CIPHER_SUITE_WEP104:
                        data_pad = 4;
                        break;
                case WLAN_CIPHER_SUITE_TKIP:
                        data_pad = 12;
                        break;
                case WLAN_CIPHER_SUITE_CCMP:
                        data_pad = 8;
                        break;
                }
        }
        mwl8k_add_dma_header(priv, skb, head_pad, data_pad);
}

/*
 * Packet reception for 88w8366/88w8764 AP firmware.
 */
struct mwl8k_rxd_ap {
        __le16 pkt_len;
        __u8 sq2;
        __u8 rate;
        __le32 pkt_phys_addr;
        __le32 next_rxd_phys_addr;
        __le16 qos_control;
        __le16 htsig2;
        __le32 hw_rssi_info;
        __le32 hw_noise_floor_info;
        __u8 noise_floor;
        __u8 pad0[3];
        __u8 rssi;
        __u8 rx_status;
        __u8 channel;
        __u8 rx_ctrl;
} __packed;

#define MWL8K_AP_RATE_INFO_MCS_FORMAT           0x80
#define MWL8K_AP_RATE_INFO_40MHZ                0x40
#define MWL8K_AP_RATE_INFO_RATEID(x)            ((x) & 0x3f)

#define MWL8K_AP_RX_CTRL_OWNED_BY_HOST          0x80

/* 8366/8764 AP rx_status bits */
#define MWL8K_AP_RXSTAT_DECRYPT_ERR_MASK                0x80
#define MWL8K_AP_RXSTAT_GENERAL_DECRYPT_ERR             0xFF
#define MWL8K_AP_RXSTAT_TKIP_DECRYPT_MIC_ERR            0x02
#define MWL8K_AP_RXSTAT_WEP_DECRYPT_ICV_ERR             0x04
#define MWL8K_AP_RXSTAT_TKIP_DECRYPT_ICV_ERR            0x08

static void mwl8k_rxd_ap_init(void *_rxd, dma_addr_t next_dma_addr)
{
        struct mwl8k_rxd_ap *rxd = _rxd;

        rxd->next_rxd_phys_addr = cpu_to_le32(next_dma_addr);
        rxd->rx_ctrl = MWL8K_AP_RX_CTRL_OWNED_BY_HOST;
}

static void mwl8k_rxd_ap_refill(void *_rxd, dma_addr_t addr, int len)
{
        struct mwl8k_rxd_ap *rxd = _rxd;

        rxd->pkt_len = cpu_to_le16(len);
        rxd->pkt_phys_addr = cpu_to_le32(addr);
        wmb();
        rxd->rx_ctrl = 0;
}

static int
mwl8k_rxd_ap_process(void *_rxd, struct ieee80211_rx_status *status,
                     __le16 *qos, s8 *noise)
{
        struct mwl8k_rxd_ap *rxd = _rxd;

        if (!(rxd->rx_ctrl & MWL8K_AP_RX_CTRL_OWNED_BY_HOST))
                return -1;
        rmb();

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

        status->signal = -rxd->rssi;
        *noise = -rxd->noise_floor;

        if (rxd->rate & MWL8K_AP_RATE_INFO_MCS_FORMAT) {
                status->encoding = RX_ENC_HT;
                if (rxd->rate & MWL8K_AP_RATE_INFO_40MHZ)
                        status->bw = RATE_INFO_BW_40;
                status->rate_idx = MWL8K_AP_RATE_INFO_RATEID(rxd->rate);
        } else {
                int i;

                for (i = 0; i < ARRAY_SIZE(mwl8k_rates_24); i++) {
                        if (mwl8k_rates_24[i].hw_value == rxd->rate) {
                                status->rate_idx = i;
                                break;
                        }
                }
        }

        if (rxd->channel > 14) {
                status->band = NL80211_BAND_5GHZ;
                if (!(status->encoding == RX_ENC_HT) &&
                    status->rate_idx >= MWL8K_LEGACY_5G_RATE_OFFSET)
                        status->rate_idx -= MWL8K_LEGACY_5G_RATE_OFFSET;
        } else {
                status->band = NL80211_BAND_2GHZ;
        }
        status->freq = ieee80211_channel_to_frequency(rxd->channel,
                                                      status->band);

        *qos = rxd->qos_control;

        if ((rxd->rx_status != MWL8K_AP_RXSTAT_GENERAL_DECRYPT_ERR) &&
            (rxd->rx_status & MWL8K_AP_RXSTAT_DECRYPT_ERR_MASK) &&
            (rxd->rx_status & MWL8K_AP_RXSTAT_TKIP_DECRYPT_MIC_ERR))
                status->flag |= RX_FLAG_MMIC_ERROR;

        return le16_to_cpu(rxd->pkt_len);
}

static struct rxd_ops rxd_ap_ops = {
        .rxd_size       = sizeof(struct mwl8k_rxd_ap),
        .rxd_init       = mwl8k_rxd_ap_init,
        .rxd_refill     = mwl8k_rxd_ap_refill,
        .rxd_process    = mwl8k_rxd_ap_process,
};

/*
 * Packet reception for STA firmware.
 */
struct mwl8k_rxd_sta {
        __le16 pkt_len;
        __u8 link_quality;
        __u8 noise_level;
        __le32 pkt_phys_addr;
        __le32 next_rxd_phys_addr;
        __le16 qos_control;
        __le16 rate_info;
        __le32 pad0[4];
        __u8 rssi;
        __u8 channel;
        __le16 pad1;
        __u8 rx_ctrl;
        __u8 rx_status;
        __u8 pad2[2];
} __packed;

#define MWL8K_STA_RATE_INFO_SHORTPRE            0x8000
#define MWL8K_STA_RATE_INFO_ANTSELECT(x)        (((x) >> 11) & 0x3)
#define MWL8K_STA_RATE_INFO_RATEID(x)           (((x) >> 3) & 0x3f)
#define MWL8K_STA_RATE_INFO_40MHZ               0x0004
#define MWL8K_STA_RATE_INFO_SHORTGI             0x0002
#define MWL8K_STA_RATE_INFO_MCS_FORMAT          0x0001

#define MWL8K_STA_RX_CTRL_OWNED_BY_HOST         0x02
#define MWL8K_STA_RX_CTRL_DECRYPT_ERROR         0x04
/* ICV=0 or MIC=1 */
#define MWL8K_STA_RX_CTRL_DEC_ERR_TYPE          0x08
/* Key is uploaded only in failure case */
#define MWL8K_STA_RX_CTRL_KEY_INDEX                     0x30

static void mwl8k_rxd_sta_init(void *_rxd, dma_addr_t next_dma_addr)
{
        struct mwl8k_rxd_sta *rxd = _rxd;

        rxd->next_rxd_phys_addr = cpu_to_le32(next_dma_addr);
        rxd->rx_ctrl = MWL8K_STA_RX_CTRL_OWNED_BY_HOST;
}

static void mwl8k_rxd_sta_refill(void *_rxd, dma_addr_t addr, int len)
{
        struct mwl8k_rxd_sta *rxd = _rxd;

        rxd->pkt_len = cpu_to_le16(len);
        rxd->pkt_phys_addr = cpu_to_le32(addr);
        wmb();
        rxd->rx_ctrl = 0;
}

static int
mwl8k_rxd_sta_process(void *_rxd, struct ieee80211_rx_status *status,
                       __le16 *qos, s8 *noise)
{
        struct mwl8k_rxd_sta *rxd = _rxd;
        u16 rate_info;

        if (!(rxd->rx_ctrl & MWL8K_STA_RX_CTRL_OWNED_BY_HOST))
                return -1;
        rmb();

        rate_info = le16_to_cpu(rxd->rate_info);

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

        status->signal = -rxd->rssi;
        *noise = -rxd->noise_level;
        status->antenna = MWL8K_STA_RATE_INFO_ANTSELECT(rate_info);
        status->rate_idx = MWL8K_STA_RATE_INFO_RATEID(rate_info);

        if (rate_info & MWL8K_STA_RATE_INFO_SHORTPRE)
                status->enc_flags |= RX_ENC_FLAG_SHORTPRE;
        if (rate_info & MWL8K_STA_RATE_INFO_40MHZ)
                status->bw = RATE_INFO_BW_40;
        if (rate_info & MWL8K_STA_RATE_INFO_SHORTGI)
                status->enc_flags |= RX_ENC_FLAG_SHORT_GI;
        if (rate_info & MWL8K_STA_RATE_INFO_MCS_FORMAT)
                status->encoding = RX_ENC_HT;

        if (rxd->channel > 14) {
                status->band = NL80211_BAND_5GHZ;
                if (!(status->encoding == RX_ENC_HT) &&
                    status->rate_idx >= MWL8K_LEGACY_5G_RATE_OFFSET)
                        status->rate_idx -= MWL8K_LEGACY_5G_RATE_OFFSET;
        } else {
                status->band = NL80211_BAND_2GHZ;
        }
        status->freq = ieee80211_channel_to_frequency(rxd->channel,
                                                      status->band);

        *qos = rxd->qos_control;
        if ((rxd->rx_ctrl & MWL8K_STA_RX_CTRL_DECRYPT_ERROR) &&
            (rxd->rx_ctrl & MWL8K_STA_RX_CTRL_DEC_ERR_TYPE))
                status->flag |= RX_FLAG_MMIC_ERROR;

        return le16_to_cpu(rxd->pkt_len);
}

static struct rxd_ops rxd_sta_ops = {
        .rxd_size       = sizeof(struct mwl8k_rxd_sta),
        .rxd_init       = mwl8k_rxd_sta_init,
        .rxd_refill     = mwl8k_rxd_sta_refill,
        .rxd_process    = mwl8k_rxd_sta_process,
};


#define MWL8K_RX_DESCS          256
#define MWL8K_RX_MAXSZ          3800

static int mwl8k_rxq_init(struct ieee80211_hw *hw, int index)
{
        struct mwl8k_priv *priv = hw->priv;
        struct mwl8k_rx_queue *rxq = priv->rxq + index;
        int size;
        int i;

        rxq->rxd_count = 0;
        rxq->head = 0;
        rxq->tail = 0;

        size = MWL8K_RX_DESCS * priv->rxd_ops->rxd_size;

        rxq->rxd = dma_alloc_coherent(&priv->pdev->dev, size, &rxq->rxd_dma,
                                      GFP_KERNEL);
        if (rxq->rxd == NULL) {
                wiphy_err(hw->wiphy, "failed to alloc RX descriptors\n");
                return -ENOMEM;
        }

        rxq->buf = kcalloc(MWL8K_RX_DESCS, sizeof(*rxq->buf), GFP_KERNEL);
        if (rxq->buf == NULL) {
                dma_free_coherent(&priv->pdev->dev, size, rxq->rxd,
                                  rxq->rxd_dma);
                return -ENOMEM;
        }

        for (i = 0; i < MWL8K_RX_DESCS; i++) {
                int desc_size;
                void *rxd;
                int nexti;
                dma_addr_t next_dma_addr;

                desc_size = priv->rxd_ops->rxd_size;
                rxd = rxq->rxd + (i * priv->rxd_ops->rxd_size);

                nexti = i + 1;
                if (nexti == MWL8K_RX_DESCS)
                        nexti = 0;
                next_dma_addr = rxq->rxd_dma + (nexti * desc_size);

                priv->rxd_ops->rxd_init(rxd, next_dma_addr);
        }

        return 0;
}

static int rxq_refill(struct ieee80211_hw *hw, int index, int limit)
{
        struct mwl8k_priv *priv = hw->priv;
        struct mwl8k_rx_queue *rxq = priv->rxq + index;
        int refilled = 0;

        while (rxq->rxd_count < MWL8K_RX_DESCS && limit--) {
                struct sk_buff *skb;
                dma_addr_t addr;
                int rx;
                void *rxd;

                skb = dev_alloc_skb(MWL8K_RX_MAXSZ);
                if (skb == NULL)
                        break;

                addr = dma_map_single(&priv->pdev->dev, skb->data,
                                      MWL8K_RX_MAXSZ, DMA_FROM_DEVICE);

                rxq->rxd_count++;
                rx = rxq->tail++;
                if (rxq->tail == MWL8K_RX_DESCS)
                        rxq->tail = 0;
                rxq->buf[rx].skb = skb;
                dma_unmap_addr_set(&rxq->buf[rx], dma, addr);

                rxd = rxq->rxd + (rx * priv->rxd_ops->rxd_size);
                priv->rxd_ops->rxd_refill(rxd, addr, MWL8K_RX_MAXSZ);

                refilled++;
        }

        return refilled;
}

/* Must be called only when the card's reception is completely halted */
static void mwl8k_rxq_deinit(struct ieee80211_hw *hw, int index)
{
        struct mwl8k_priv *priv = hw->priv;
        struct mwl8k_rx_queue *rxq = priv->rxq + index;
        int i;

        if (rxq->rxd == NULL)
                return;

        for (i = 0; i < MWL8K_RX_DESCS; i++) {
                if (rxq->buf[i].skb != NULL) {
                        dma_unmap_single(&priv->pdev->dev,
                                         dma_unmap_addr(&rxq->buf[i], dma),
                                         MWL8K_RX_MAXSZ, DMA_FROM_DEVICE);
                        dma_unmap_addr_set(&rxq->buf[i], dma, 0);

                        kfree_skb(rxq->buf[i].skb);
                        rxq->buf[i].skb = NULL;
                }
        }

        kfree(rxq->buf);
        rxq->buf = NULL;

        dma_free_coherent(&priv->pdev->dev,
                          MWL8K_RX_DESCS * priv->rxd_ops->rxd_size, rxq->rxd,
                          rxq->rxd_dma);
        rxq->rxd = NULL;
}


/*
 * Scan a list of BSSIDs to process for finalize join.
 * Allows for extension to process multiple BSSIDs.
 */
static inline int
mwl8k_capture_bssid(struct mwl8k_priv *priv, struct ieee80211_hdr *wh)
{
        return priv->capture_beacon &&
                ieee80211_is_beacon(wh->frame_control) &&
                ether_addr_equal_64bits(wh->addr3, priv->capture_bssid);
}

static inline void mwl8k_save_beacon(struct ieee80211_hw *hw,
                                     struct sk_buff *skb)
{
        struct mwl8k_priv *priv = hw->priv;

        priv->capture_beacon = false;
        eth_zero_addr(priv->capture_bssid);

        /*
         * Use GFP_ATOMIC as rxq_process is called from
         * the primary interrupt handler, memory allocation call
         * must not sleep.
         */
        priv->beacon_skb = skb_copy(skb, GFP_ATOMIC);
        if (priv->beacon_skb != NULL)
                ieee80211_queue_work(hw, &priv->finalize_join_worker);
}

static inline struct mwl8k_vif *mwl8k_find_vif_bss(struct list_head *vif_list,
                                                   u8 *bssid)
{
        struct mwl8k_vif *mwl8k_vif;

        list_for_each_entry(mwl8k_vif,
                            vif_list, list) {
                if (memcmp(bssid, mwl8k_vif->bssid,
                           ETH_ALEN) == 0)
                        return mwl8k_vif;
        }

        return NULL;
}

static int rxq_process(struct ieee80211_hw *hw, int index, int limit)
{
        struct mwl8k_priv *priv = hw->priv;
        struct mwl8k_vif *mwl8k_vif = NULL;
        struct mwl8k_rx_queue *rxq = priv->rxq + index;
        int processed;

        processed = 0;
        while (rxq->rxd_count && limit--) {
                struct sk_buff *skb;
                void *rxd;
                int pkt_len;
                struct ieee80211_rx_status status;
                struct ieee80211_hdr *wh;
                __le16 qos;

                skb = rxq->buf[rxq->head].skb;
                if (skb == NULL)
                        break;

                rxd = rxq->rxd + (rxq->head * priv->rxd_ops->rxd_size);

                pkt_len = priv->rxd_ops->rxd_process(rxd, &status, &qos,
                                                        &priv->noise);
                if (pkt_len < 0)
                        break;

                rxq->buf[rxq->head].skb = NULL;

                dma_unmap_single(&priv->pdev->dev,
                                 dma_unmap_addr(&rxq->buf[rxq->head], dma),
                                 MWL8K_RX_MAXSZ, DMA_FROM_DEVICE);
                dma_unmap_addr_set(&rxq->buf[rxq->head], dma, 0);

                rxq->head++;
                if (rxq->head == MWL8K_RX_DESCS)
                        rxq->head = 0;

                rxq->rxd_count--;

                wh = &((struct mwl8k_dma_data *)skb->data)->wh;

                /*
                 * Check for a pending join operation.  Save a
                 * copy of the beacon and schedule a tasklet to
                 * send a FINALIZE_JOIN command to the firmware.
                 */
                if (mwl8k_capture_bssid(priv, (void *)skb->data))
                        mwl8k_save_beacon(hw, skb);

                if (ieee80211_has_protected(wh->frame_control)) {

                        /* Check if hw crypto has been enabled for
                         * this bss. If yes, set the status flags
                         * accordingly
                         */
                        mwl8k_vif = mwl8k_find_vif_bss(&priv->vif_list,
                                                                wh->addr1);

                        if (mwl8k_vif != NULL &&
                            mwl8k_vif->is_hw_crypto_enabled) {
                                /*
                                 * When MMIC ERROR is encountered
                                 * by the firmware, payload is
                                 * dropped and only 32 bytes of
                                 * mwl8k Firmware header is sent
                                 * to the host.
                                 *
                                 * We need to add four bytes of
                                 * key information.  In it
                                 * MAC80211 expects keyidx set to
                                 * 0 for triggering Counter
                                 * Measure of MMIC failure.
                                 */
                                if (status.flag & RX_FLAG_MMIC_ERROR) {
                                        struct mwl8k_dma_data *tr;
                                        tr = (struct mwl8k_dma_data *)skb->data;
                                        memset((void *)&(tr->data), 0, 4);
                                        pkt_len += 4;
                                }

                                if (!ieee80211_is_auth(wh->frame_control))
                                        status.flag |= RX_FLAG_IV_STRIPPED |
                                                       RX_FLAG_DECRYPTED |
                                                       RX_FLAG_MMIC_STRIPPED;
                        }
                }

                skb_put(skb, pkt_len);
                mwl8k_remove_dma_header(skb, qos);
                memcpy(IEEE80211_SKB_RXCB(skb), &status, sizeof(status));
                ieee80211_rx_irqsafe(hw, skb);

                processed++;
        }

        return processed;
}


/*
 * Packet transmission.
 */

#define MWL8K_TXD_STATUS_OK                     0x00000001
#define MWL8K_TXD_STATUS_OK_RETRY               0x00000002
#define MWL8K_TXD_STATUS_OK_MORE_RETRY          0x00000004
#define MWL8K_TXD_STATUS_MULTICAST_TX           0x00000008
#define MWL8K_TXD_STATUS_FW_OWNED               0x80000000

#define MWL8K_QOS_QLEN_UNSPEC                   0xff00
#define MWL8K_QOS_ACK_POLICY_MASK               0x0060
#define MWL8K_QOS_ACK_POLICY_NORMAL             0x0000
#define MWL8K_QOS_ACK_POLICY_BLOCKACK           0x0060
#define MWL8K_QOS_EOSP                          0x0010

struct mwl8k_tx_desc {
        __le32 status;
        __u8 data_rate;
        __u8 tx_priority;
        __le16 qos_control;
        __le32 pkt_phys_addr;
        __le16 pkt_len;
        __u8 dest_MAC_addr[ETH_ALEN];
        __le32 next_txd_phys_addr;
        __le32 timestamp;
        __le16 rate_info;
        __u8 peer_id;
        __u8 tx_frag_cnt;
} __packed;

#define MWL8K_TX_DESCS          128

static int mwl8k_txq_init(struct ieee80211_hw *hw, int index)
{
        struct mwl8k_priv *priv = hw->priv;
        struct mwl8k_tx_queue *txq = priv->txq + index;
        int size;
        int i;

        txq->len = 0;
        txq->head = 0;
        txq->tail = 0;

        size = MWL8K_TX_DESCS * sizeof(struct mwl8k_tx_desc);

        txq->txd = dma_alloc_coherent(&priv->pdev->dev, size, &txq->txd_dma,
                                      GFP_KERNEL);
        if (txq->txd == NULL) {
                wiphy_err(hw->wiphy, "failed to alloc TX descriptors\n");
                return -ENOMEM;
        }

        txq->skb = kcalloc(MWL8K_TX_DESCS, sizeof(*txq->skb), GFP_KERNEL);
        if (txq->skb == NULL) {
                dma_free_coherent(&priv->pdev->dev, size, txq->txd,
                                  txq->txd_dma);
                txq->txd = NULL;
                return -ENOMEM;
        }

        for (i = 0; i < MWL8K_TX_DESCS; i++) {
                struct mwl8k_tx_desc *tx_desc;
                int nexti;

                tx_desc = txq->txd + i;
                nexti = (i + 1) % MWL8K_TX_DESCS;

                tx_desc->status = 0;
                tx_desc->next_txd_phys_addr =
                        cpu_to_le32(txq->txd_dma + nexti * sizeof(*tx_desc));
        }

        return 0;
}

static inline void mwl8k_tx_start(struct mwl8k_priv *priv)
{
        iowrite32(MWL8K_H2A_INT_PPA_READY,
                priv->regs + MWL8K_HIU_H2A_INTERRUPT_EVENTS);
        iowrite32(MWL8K_H2A_INT_DUMMY,
                priv->regs + MWL8K_HIU_H2A_INTERRUPT_EVENTS);
        ioread32(priv->regs + MWL8K_HIU_INT_CODE);
}

static void mwl8k_dump_tx_rings(struct ieee80211_hw *hw)
{
        struct mwl8k_priv *priv = hw->priv;
        int i;

        for (i = 0; i < mwl8k_tx_queues(priv); i++) {
                struct mwl8k_tx_queue *txq = priv->txq + i;
                int fw_owned = 0;
                int drv_owned = 0;
                int unused = 0;
                int desc;

                for (desc = 0; desc < MWL8K_TX_DESCS; desc++) {
                        struct mwl8k_tx_desc *tx_desc = txq->txd + desc;
                        u32 status;

                        status = le32_to_cpu(tx_desc->status);
                        if (status & MWL8K_TXD_STATUS_FW_OWNED)
                                fw_owned++;
                        else
                                drv_owned++;

                        if (tx_desc->pkt_len == 0)
                                unused++;
                }

                wiphy_err(hw->wiphy,
                          "txq[%d] len=%d head=%d tail=%d "
                          "fw_owned=%d drv_owned=%d unused=%d\n",
                          i,
                          txq->len, txq->head, txq->tail,
                          fw_owned, drv_owned, unused);
        }
}

/*
 * Must be called with priv->fw_mutex held and tx queues stopped.
 */
#define MWL8K_TX_WAIT_TIMEOUT_MS        5000

static int mwl8k_tx_wait_empty(struct ieee80211_hw *hw)
{
        struct mwl8k_priv *priv = hw->priv;
        DECLARE_COMPLETION_ONSTACK(tx_wait);
        int retry;
        int rc;

        might_sleep();

        /* Since fw restart is in progress, allow only the firmware
         * commands from the restart code and block the other
         * commands since they are going to fail in any case since
         * the firmware has crashed
         */
        if (priv->hw_restart_in_progress) {
                if (priv->hw_restart_owner == current)
                        return 0;
                else
                        return -EBUSY;
        }

        if (atomic_read(&priv->watchdog_event_pending))
                return 0;

        /*
         * The TX queues are stopped at this point, so this test
         * doesn't need to take ->tx_lock.
         */
        if (!priv->pending_tx_pkts)
                return 0;

        retry = 1;
        rc = 0;

        spin_lock_bh(&priv->tx_lock);
        priv->tx_wait = &tx_wait;
        while (!rc) {
                int oldcount;
                unsigned long timeout;

                oldcount = priv->pending_tx_pkts;

                spin_unlock_bh(&priv->tx_lock);
                timeout = wait_for_completion_timeout(&tx_wait,
                            msecs_to_jiffies(MWL8K_TX_WAIT_TIMEOUT_MS));

                if (atomic_read(&priv->watchdog_event_pending)) {
                        spin_lock_bh(&priv->tx_lock);
                        priv->tx_wait = NULL;
                        spin_unlock_bh(&priv->tx_lock);
                        return 0;
                }

                spin_lock_bh(&priv->tx_lock);

                if (timeout || !priv->pending_tx_pkts) {
                        WARN_ON(priv->pending_tx_pkts);
                        if (retry)
                                wiphy_notice(hw->wiphy, "tx rings drained\n");
                        break;
                }

                if (retry) {
                        mwl8k_tx_start(priv);
                        retry = 0;
                        continue;
                }

                if (priv->pending_tx_pkts < oldcount) {
                        wiphy_notice(hw->wiphy,
                                     "waiting for tx rings to drain (%d -> %d pkts)\n",
                                     oldcount, priv->pending_tx_pkts);
                        retry = 1;
                        continue;
                }

                priv->tx_wait = NULL;

                wiphy_err(hw->wiphy, "tx rings stuck for %d ms\n",
                          MWL8K_TX_WAIT_TIMEOUT_MS);
                mwl8k_dump_tx_rings(hw);
                priv->hw_restart_in_progress = true;
                ieee80211_queue_work(hw, &priv->fw_reload);

                rc = -ETIMEDOUT;
        }
        priv->tx_wait = NULL;
        spin_unlock_bh(&priv->tx_lock);

        return rc;
}

#define MWL8K_TXD_SUCCESS(status)                               \
        ((status) & (MWL8K_TXD_STATUS_OK |                      \
                     MWL8K_TXD_STATUS_OK_RETRY |                \
                     MWL8K_TXD_STATUS_OK_MORE_RETRY))

static int mwl8k_tid_queue_mapping(u8 tid)
{
        BUG_ON(tid > 7);

        switch (tid) {
        case 0:
        case 3:
                return IEEE80211_AC_BE;
        case 1:
        case 2:
                return IEEE80211_AC_BK;
        case 4:
        case 5:
                return IEEE80211_AC_VI;
        case 6:
        case 7:
                return IEEE80211_AC_VO;
        default:
                return -1;
        }
}

/* The firmware will fill in the rate information
 * for each packet that gets queued in the hardware
 * and these macros will interpret that info.
 */

#define RI_FORMAT(a)              (a & 0x0001)
#define RI_RATE_ID_MCS(a)        ((a & 0x01f8) >> 3)

static int
mwl8k_txq_reclaim(struct ieee80211_hw *hw, int index, int limit, int force)
{
        struct mwl8k_priv *priv = hw->priv;
        struct mwl8k_tx_queue *txq = priv->txq + index;
        int processed;

        processed = 0;
        while (txq->len > 0 && limit--) {
                int tx;
                struct mwl8k_tx_desc *tx_desc;
                unsigned long addr;
                int size;
                struct sk_buff *skb;
                struct ieee80211_tx_info *info;
                u32 status;
                struct ieee80211_sta *sta;
                struct mwl8k_sta *sta_info = NULL;
                u16 rate_info;
                struct ieee80211_hdr *wh;

                tx = txq->head;
                tx_desc = txq->txd + tx;

                status = le32_to_cpu(tx_desc->status);

                if (status & MWL8K_TXD_STATUS_FW_OWNED) {
                        if (!force)
                                break;
                        tx_desc->status &=
                                ~cpu_to_le32(MWL8K_TXD_STATUS_FW_OWNED);
                }

                txq->head = (tx + 1) % MWL8K_TX_DESCS;
                BUG_ON(txq->len == 0);
                txq->len--;
                priv->pending_tx_pkts--;

                addr = le32_to_cpu(tx_desc->pkt_phys_addr);
                size = le16_to_cpu(tx_desc->pkt_len);
                skb = txq->skb[tx];
                txq->skb[tx] = NULL;

                BUG_ON(skb == NULL);
                dma_unmap_single(&priv->pdev->dev, addr, size, DMA_TO_DEVICE);

                mwl8k_remove_dma_header(skb, tx_desc->qos_control);

                wh = (struct ieee80211_hdr *) skb->data;

                /* Mark descriptor as unused */
                tx_desc->pkt_phys_addr = 0;
                tx_desc->pkt_len = 0;

                info = IEEE80211_SKB_CB(skb);
                if (ieee80211_is_data(wh->frame_control)) {
                        rcu_read_lock();
                        sta = ieee80211_find_sta_by_ifaddr(hw, wh->addr1,
                                                           wh->addr2);
                        if (sta) {
                                sta_info = MWL8K_STA(sta);
                                BUG_ON(sta_info == NULL);
                                rate_info = le16_to_cpu(tx_desc->rate_info);
                                /* If rate is < 6.5 Mpbs for an ht station
                                 * do not form an ampdu. If the station is a
                                 * legacy station (format = 0), do not form an
                                 * ampdu
                                 */
                                if (RI_RATE_ID_MCS(rate_info) < 1 ||
                                    RI_FORMAT(rate_info) == 0) {
                                        sta_info->is_ampdu_allowed = false;
                                } else {
                                        sta_info->is_ampdu_allowed = true;
                                }
                        }
                        rcu_read_unlock();
                }

                ieee80211_tx_info_clear_status(info);

                /* Rate control is happening in the firmware.
                 * Ensure no tx rate is being reported.
                 */
                info->status.rates[0].idx = -1;
                info->status.rates[0].count = 1;

                if (MWL8K_TXD_SUCCESS(status))
                        info->flags |= IEEE80211_TX_STAT_ACK;

                ieee80211_tx_status_irqsafe(hw, skb);

                processed++;
        }

        return processed;
}

/* must be called only when the card's transmit is completely halted */
static void mwl8k_txq_deinit(struct ieee80211_hw *hw, int index)
{
        struct mwl8k_priv *priv = hw->priv;
        struct mwl8k_tx_queue *txq = priv->txq + index;

        if (txq->txd == NULL)
                return;

        mwl8k_txq_reclaim(hw, index, INT_MAX, 1);

        kfree(txq->skb);
        txq->skb = NULL;

        dma_free_coherent(&priv->pdev->dev,
                          MWL8K_TX_DESCS * sizeof(struct mwl8k_tx_desc),
                          txq->txd, txq->txd_dma);
        txq->txd = NULL;
}

/* caller must hold priv->stream_lock when calling the stream functions */
static struct mwl8k_ampdu_stream *
mwl8k_add_stream(struct ieee80211_hw *hw, struct ieee80211_sta *sta, u8 tid)
{
        struct mwl8k_ampdu_stream *stream;
        struct mwl8k_priv *priv = hw->priv;
        int i;

        for (i = 0; i < MWL8K_NUM_AMPDU_STREAMS; i++) {
                stream = &priv->ampdu[i];
                if (stream->state == AMPDU_NO_STREAM) {
                        stream->sta = sta;
                        stream->state = AMPDU_STREAM_NEW;
                        stream->tid = tid;
                        stream->idx = i;
                        wiphy_debug(hw->wiphy, "Added a new stream for %pM %d",
                                    sta->addr, tid);
                        return stream;
                }
        }
        return NULL;
}

static int
mwl8k_start_stream(struct ieee80211_hw *hw, struct mwl8k_ampdu_stream *stream)
{
        int ret;

        /* if the stream has already been started, don't start it again */
        if (stream->state != AMPDU_STREAM_NEW)
                return 0;
        ret = ieee80211_start_tx_ba_session(stream->sta, stream->tid, 0);
        if (ret)
                wiphy_debug(hw->wiphy, "Failed to start stream for %pM %d: "
                            "%d\n", stream->sta->addr, stream->tid, ret);
        else
                wiphy_debug(hw->wiphy, "Started stream for %pM %d\n",
                            stream->sta->addr, stream->tid);
        return ret;
}

static void
mwl8k_remove_stream(struct ieee80211_hw *hw, struct mwl8k_ampdu_stream *stream)
{
        wiphy_debug(hw->wiphy, "Remove stream for %pM %d\n", stream->sta->addr,
                    stream->tid);
        memset(stream, 0, sizeof(*stream));
}

static struct mwl8k_ampdu_stream *
mwl8k_lookup_stream(struct ieee80211_hw *hw, u8 *addr, u8 tid)
{
        struct mwl8k_priv *priv = hw->priv;
        int i;

        for (i = 0; i < MWL8K_NUM_AMPDU_STREAMS; i++) {
                struct mwl8k_ampdu_stream *stream;
                stream = &priv->ampdu[i];
                if (stream->state == AMPDU_NO_STREAM)
                        continue;
                if (!memcmp(stream->sta->addr, addr, ETH_ALEN) &&
                    stream->tid == tid)
                        return stream;
        }
        return NULL;
}

#define MWL8K_AMPDU_PACKET_THRESHOLD 64
static inline bool mwl8k_ampdu_allowed(struct ieee80211_sta *sta, u8 tid)
{
        struct mwl8k_sta *sta_info = MWL8K_STA(sta);
        struct tx_traffic_info *tx_stats;

        BUG_ON(tid >= MWL8K_MAX_TID);
        tx_stats = &sta_info->tx_stats[tid];

        return sta_info->is_ampdu_allowed &&
                tx_stats->pkts > MWL8K_AMPDU_PACKET_THRESHOLD;
}

static inline void mwl8k_tx_count_packet(struct ieee80211_sta *sta, u8 tid)
{
        struct mwl8k_sta *sta_info = MWL8K_STA(sta);
        struct tx_traffic_info *tx_stats;

        BUG_ON(tid >= MWL8K_MAX_TID);
        tx_stats = &sta_info->tx_stats[tid];

        if (tx_stats->start_time == 0)
                tx_stats->start_time = jiffies;

        /* reset the packet count after each second elapses.  If the number of
         * packets ever exceeds the ampdu_min_traffic threshold, we will allow
         * an ampdu stream to be started.
         */
        if (jiffies - tx_stats->start_time > HZ) {
                tx_stats->pkts = 0;
                tx_stats->start_time = 0;
        } else
                tx_stats->pkts++;
}

/* The hardware ampdu queues start from 5.
 * txpriorities for ampdu queues are
 * 5 6 7 0 1 2 3 4 ie., queue 5 is highest
 * and queue 3 is lowest (queue 4 is reserved)
 */
#define BA_QUEUE                5

static void
mwl8k_txq_xmit(struct ieee80211_hw *hw,
               int index,
               struct ieee80211_sta *sta,
               struct sk_buff *skb)
{
        struct mwl8k_priv *priv = hw->priv;
        struct ieee80211_tx_info *tx_info;
        struct mwl8k_vif *mwl8k_vif;
        struct ieee80211_hdr *wh;
        struct mwl8k_tx_queue *txq;
        struct mwl8k_tx_desc *tx;
        dma_addr_t dma;
        u32 txstatus;
        u8 txdatarate;
        u16 qos;
        int txpriority;
        u8 tid = 0;
        struct mwl8k_ampdu_stream *stream = NULL;
        bool start_ba_session = false;
        bool mgmtframe = false;
        struct ieee80211_mgmt *mgmt = (struct ieee80211_mgmt *)skb->data;
        bool eapol_frame = false;

        wh = (struct ieee80211_hdr *)skb->data;
        if (ieee80211_is_data_qos(wh->frame_control))
                qos = le16_to_cpu(*((__le16 *)ieee80211_get_qos_ctl(wh)));
        else
                qos = 0;

        if (skb->protocol == cpu_to_be16(ETH_P_PAE))
                eapol_frame = true;

        if (ieee80211_is_mgmt(wh->frame_control))
                mgmtframe = true;

        if (priv->ap_fw)
                mwl8k_encapsulate_tx_frame(priv, skb);
        else
                mwl8k_add_dma_header(priv, skb, 0, 0);

        wh = &((struct mwl8k_dma_data *)skb->data)->wh;

        tx_info = IEEE80211_SKB_CB(skb);
        mwl8k_vif = MWL8K_VIF(tx_info->control.vif);

        if (tx_info->flags & IEEE80211_TX_CTL_ASSIGN_SEQ) {
                wh->seq_ctrl &= cpu_to_le16(IEEE80211_SCTL_FRAG);
                wh->seq_ctrl |= cpu_to_le16(mwl8k_vif->seqno);
                mwl8k_vif->seqno += 0x10;
        }

        /* Setup firmware control bit fields for each frame type.  */
        txstatus = 0;
        txdatarate = 0;
        if (ieee80211_is_mgmt(wh->frame_control) ||
            ieee80211_is_ctl(wh->frame_control)) {
                txdatarate = 0;
                qos |= MWL8K_QOS_QLEN_UNSPEC | MWL8K_QOS_EOSP;
        } else if (ieee80211_is_data(wh->frame_control)) {
                txdatarate = 1;
                if (is_multicast_ether_addr(wh->addr1))
                        txstatus |= MWL8K_TXD_STATUS_MULTICAST_TX;

                qos &= ~MWL8K_QOS_ACK_POLICY_MASK;
                if (tx_info->flags & IEEE80211_TX_CTL_AMPDU)
                        qos |= MWL8K_QOS_ACK_POLICY_BLOCKACK;
                else
                        qos |= MWL8K_QOS_ACK_POLICY_NORMAL;
        }

        /* Queue ADDBA request in the respective data queue.  While setting up
         * the ampdu stream, mac80211 queues further packets for that
         * particular ra/tid pair.  However, packets piled up in the hardware
         * for that ra/tid pair will still go out. ADDBA request and the
         * related data packets going out from different queues asynchronously
         * will cause a shift in the receiver window which might result in
         * ampdu packets getting dropped at the receiver after the stream has
         * been setup.
         */
        if (unlikely(ieee80211_is_action(wh->frame_control) &&
            mgmt->u.action.category == WLAN_CATEGORY_BACK &&
            mgmt->u.action.u.addba_req.action_code == WLAN_ACTION_ADDBA_REQ &&
            priv->ap_fw)) {
                u16 capab = le16_to_cpu(mgmt->u.action.u.addba_req.capab);
                tid = (capab & IEEE80211_ADDBA_PARAM_TID_MASK) >> 2;
                index = mwl8k_tid_queue_mapping(tid);
        }

        txpriority = index;

        if (priv->ap_fw && sta && sta->ht_cap.ht_supported && !eapol_frame &&
            ieee80211_is_data_qos(wh->frame_control)) {
                tid = qos & 0xf;
                mwl8k_tx_count_packet(sta, tid);
                spin_lock(&priv->stream_lock);
                stream = mwl8k_lookup_stream(hw, sta->addr, tid);
                if (stream != NULL) {
                        if (stream->state == AMPDU_STREAM_ACTIVE) {
                                WARN_ON(!(qos & MWL8K_QOS_ACK_POLICY_BLOCKACK));
                                txpriority = (BA_QUEUE + stream->idx) %
                                             TOTAL_HW_TX_QUEUES;
                                if (stream->idx <= 1)
                                        index = stream->idx +

                                                MWL8K_TX_WMM_QUEUES;

                        } else if (stream->state == AMPDU_STREAM_NEW) {
                                /* We get here if the driver sends us packets
                                 * after we've initiated a stream, but before
                                 * our ampdu_action routine has been called
                                 * with IEEE80211_AMPDU_TX_START to get the SSN
                                 * for the ADDBA request.  So this packet can
                                 * go out with no risk of sequence number
                                 * mismatch.  No special handling is required.
                                 */
                        } else {
                                /* Drop packets that would go out after the
                                 * ADDBA request was sent but before the ADDBA
                                 * response is received.  If we don't do this,
                                 * the recipient would probably receive it
                                 * after the ADDBA request with SSN 0.  This
                                 * will cause the recipient's BA receive window
                                 * to shift, which would cause the subsequent
                                 * packets in the BA stream to be discarded.
                                 * mac80211 queues our packets for us in this
                                 * case, so this is really just a safety check.
                                 */
                                wiphy_warn(hw->wiphy,
                                           "Cannot send packet while ADDBA "
                                           "dialog is underway.\n");
                                spin_unlock(&priv->stream_lock);
                                dev_kfree_skb(skb);
                                return;
                        }
                } else {
                        /* Defer calling mwl8k_start_stream so that the current
                         * skb can go out before the ADDBA request.  This
                         * prevents sequence number mismatch at the recepient
                         * as described above.
                         */
                        if (mwl8k_ampdu_allowed(sta, tid)) {
                                stream = mwl8k_add_stream(hw, sta, tid);
                                if (stream != NULL)
                                        start_ba_session = true;
                        }
                }
                spin_unlock(&priv->stream_lock);
        } else {
                qos &= ~MWL8K_QOS_ACK_POLICY_MASK;
                qos |= MWL8K_QOS_ACK_POLICY_NORMAL;
        }

        dma = dma_map_single(&priv->pdev->dev, skb->data, skb->len,
                             DMA_TO_DEVICE);

        if (dma_mapping_error(&priv->pdev->dev, dma)) {
                wiphy_debug(hw->wiphy,
                            "failed to dma map skb, dropping TX frame.\n");
                if (start_ba_session) {
                        spin_lock(&priv->stream_lock);
                        mwl8k_remove_stream(hw, stream);
                        spin_unlock(&priv->stream_lock);
                }
                dev_kfree_skb(skb);
                return;
        }

        spin_lock_bh(&priv->tx_lock);

        txq = priv->txq + index;

        /* Mgmt frames that go out frequently are probe
         * responses. Other mgmt frames got out relatively
         * infrequently. Hence reserve 2 buffers so that
         * other mgmt frames do not get dropped due to an
         * already queued probe response in one of the
         * reserved buffers.
         */

        if (txq->len >= MWL8K_TX_DESCS - 2) {
                if (!mgmtframe || txq->len == MWL8K_TX_DESCS) {
                        if (start_ba_session) {
                                spin_lock(&priv->stream_lock);
                                mwl8k_remove_stream(hw, stream);
                                spin_unlock(&priv->stream_lock);
                        }
                        mwl8k_tx_start(priv);
                        spin_unlock_bh(&priv->tx_lock);
                        dma_unmap_single(&priv->pdev->dev, dma, skb->len,
                                         DMA_TO_DEVICE);
                        dev_kfree_skb(skb);
                        return;
                }
        }

        BUG_ON(txq->skb[txq->tail] != NULL);
        txq->skb[txq->tail] = skb;

        tx = txq->txd + txq->tail;
        tx->data_rate = txdatarate;
        tx->tx_priority = txpriority;
        tx->qos_control = cpu_to_le16(qos);
        tx->pkt_phys_addr = cpu_to_le32(dma);
        tx->pkt_len = cpu_to_le16(skb->len);
        tx->rate_info = 0;
        if (!priv->ap_fw && sta != NULL)
                tx->peer_id = MWL8K_STA(sta)->peer_id;
        else
                tx->peer_id = 0;

        if (priv->ap_fw && ieee80211_is_data(wh->frame_control) && !eapol_frame)
                tx->timestamp = cpu_to_le32(ioread32(priv->regs +
                                                MWL8K_HW_TIMER_REGISTER));
        else
                tx->timestamp = 0;

        wmb();
        tx->status = cpu_to_le32(MWL8K_TXD_STATUS_FW_OWNED | txstatus);

        txq->len++;
        priv->pending_tx_pkts++;

        txq->tail++;
        if (txq->tail == MWL8K_TX_DESCS)
                txq->tail = 0;

        mwl8k_tx_start(priv);

        spin_unlock_bh(&priv->tx_lock);

        /* Initiate the ampdu session here */
        if (start_ba_session) {
                spin_lock(&priv->stream_lock);
                if (mwl8k_start_stream(hw, stream))
                        mwl8k_remove_stream(hw, stream);
                spin_unlock(&priv->stream_lock);
        }
}


/*
 * Firmware access.
 *
 * We have the following requirements for issuing firmware commands:
 * - Some commands require that the packet transmit path is idle when
 *   the command is issued.  (For simplicity, we'll just quiesce the
 *   transmit path for every command.)
 * - There are certain sequences of commands that need to be issued to
 *   the hardware sequentially, with no other intervening commands.
 *
 * This leads to an implementation of a "firmware lock" as a mutex that
 * can be taken recursively, and which is taken by both the low-level
 * command submission function (mwl8k_post_cmd) as well as any users of
 * that function that require issuing of an atomic sequence of commands,
 * and quiesces the transmit path whenever it's taken.
 */
static int mwl8k_fw_lock(struct ieee80211_hw *hw)
{
        struct mwl8k_priv *priv = hw->priv;

        if (priv->fw_mutex_owner != current) {
                int rc;

                mutex_lock(&priv->fw_mutex);
                ieee80211_stop_queues(hw);

                rc = mwl8k_tx_wait_empty(hw);
                if (rc) {
                        if (!priv->hw_restart_in_progress)
                                ieee80211_wake_queues(hw);

                        mutex_unlock(&priv->fw_mutex);

                        return rc;
                }

                priv->fw_mutex_owner = current;
        }

        priv->fw_mutex_depth++;

        return 0;
}

static void mwl8k_fw_unlock(struct ieee80211_hw *hw)
{
        struct mwl8k_priv *priv = hw->priv;

        if (!--priv->fw_mutex_depth) {
                if (!priv->hw_restart_in_progress)
                        ieee80211_wake_queues(hw);

                priv->fw_mutex_owner = NULL;
                mutex_unlock(&priv->fw_mutex);
        }
}

static void mwl8k_enable_bsses(struct ieee80211_hw *hw, bool enable,
                               u32 bitmap);

/*
 * Command processing.
 */

/* Timeout firmware commands after 10s */
#define MWL8K_CMD_TIMEOUT_MS    10000

static int mwl8k_post_cmd(struct ieee80211_hw *hw, struct mwl8k_cmd_pkt *cmd)
{
        DECLARE_COMPLETION_ONSTACK(cmd_wait);
        struct mwl8k_priv *priv = hw->priv;
        void __iomem *regs = priv->regs;
        dma_addr_t dma_addr;
        unsigned int dma_size;
        int rc;
        unsigned long timeout = 0;
        u8 buf[32];
        u32 bitmap = 0;

        wiphy_dbg(hw->wiphy, "Posting %s [%d]\n",
                  mwl8k_cmd_name(cmd->code, buf, sizeof(buf)), cmd->macid);

        /* Before posting firmware commands that could change the hardware
         * characteristics, make sure that all BSSes are stopped temporary.
         * Enable these stopped BSSes after completion of the commands
         */

        rc = mwl8k_fw_lock(hw);
        if (rc)
                return rc;

        if (priv->ap_fw && priv->running_bsses) {
                switch (le16_to_cpu(cmd->code)) {
                case MWL8K_CMD_SET_RF_CHANNEL:
                case MWL8K_CMD_RADIO_CONTROL:
                case MWL8K_CMD_RF_TX_POWER:
                case MWL8K_CMD_TX_POWER:
                case MWL8K_CMD_RF_ANTENNA:
                case MWL8K_CMD_RTS_THRESHOLD:
                case MWL8K_CMD_MIMO_CONFIG:
                        bitmap = priv->running_bsses;
                        mwl8k_enable_bsses(hw, false, bitmap);
                        break;
                }
        }

        cmd->result = (__force __le16) 0xffff;
        dma_size = le16_to_cpu(cmd->length);
        dma_addr = dma_map_single(&priv->pdev->dev, cmd, dma_size,
                                  DMA_BIDIRECTIONAL);
        if (dma_mapping_error(&priv->pdev->dev, dma_addr)) {
                rc = -ENOMEM;
                goto exit;
        }

        priv->hostcmd_wait = &cmd_wait;
        iowrite32(dma_addr, regs + MWL8K_HIU_GEN_PTR);
        iowrite32(MWL8K_H2A_INT_DOORBELL,
                regs + MWL8K_HIU_H2A_INTERRUPT_EVENTS);
        iowrite32(MWL8K_H2A_INT_DUMMY,
                regs + MWL8K_HIU_H2A_INTERRUPT_EVENTS);

        timeout = wait_for_completion_timeout(&cmd_wait,
                                msecs_to_jiffies(MWL8K_CMD_TIMEOUT_MS));

        priv->hostcmd_wait = NULL;


        dma_unmap_single(&priv->pdev->dev, dma_addr, dma_size,
                         DMA_BIDIRECTIONAL);

        if (!timeout) {
                wiphy_err(hw->wiphy, "Command %s timeout after %u ms\n",
                          mwl8k_cmd_name(cmd->code, buf, sizeof(buf)),
                          MWL8K_CMD_TIMEOUT_MS);
                rc = -ETIMEDOUT;
        } else {
                int ms;

                ms = MWL8K_CMD_TIMEOUT_MS - jiffies_to_msecs(timeout);

                rc = cmd->result ? -EINVAL : 0;
                if (rc)
                        wiphy_err(hw->wiphy, "Command %s error 0x%x\n",
                                  mwl8k_cmd_name(cmd->code, buf, sizeof(buf)),
                                  le16_to_cpu(cmd->result));
                else if (ms > 2000)
                        wiphy_notice(hw->wiphy, "Command %s took %d ms\n",
                                     mwl8k_cmd_name(cmd->code,
                                                    buf, sizeof(buf)),
                                     ms);
        }

exit:
        if (bitmap)
                mwl8k_enable_bsses(hw, true, bitmap);

        mwl8k_fw_unlock(hw);

        return rc;
}

static int mwl8k_post_pervif_cmd(struct ieee80211_hw *hw,
                                 struct ieee80211_vif *vif,
                                 struct mwl8k_cmd_pkt *cmd)
{
        if (vif != NULL)
                cmd->macid = MWL8K_VIF(vif)->macid;
        return mwl8k_post_cmd(hw, cmd);
}

/*
 * Setup code shared between STA and AP firmware images.
 */
static void mwl8k_setup_2ghz_band(struct ieee80211_hw *hw)
{
        struct mwl8k_priv *priv = hw->priv;

        BUILD_BUG_ON(sizeof(priv->channels_24) != sizeof(mwl8k_channels_24));
        memcpy(priv->channels_24, mwl8k_channels_24, sizeof(mwl8k_channels_24));

        BUILD_BUG_ON(sizeof(priv->rates_24) != sizeof(mwl8k_rates_24));
        memcpy(priv->rates_24, mwl8k_rates_24, sizeof(mwl8k_rates_24));

        priv->band_24.band = NL80211_BAND_2GHZ;
        priv->band_24.channels = priv->channels_24;
        priv->band_24.n_channels = ARRAY_SIZE(mwl8k_channels_24);
        priv->band_24.bitrates = priv->rates_24;
        priv->band_24.n_bitrates = ARRAY_SIZE(mwl8k_rates_24);

        hw->wiphy->bands[NL80211_BAND_2GHZ] = &priv->band_24;
}

static void mwl8k_setup_5ghz_band(struct ieee80211_hw *hw)
{
        struct mwl8k_priv *priv = hw->priv;

        BUILD_BUG_ON(sizeof(priv->channels_50) != sizeof(mwl8k_channels_50));
        memcpy(priv->channels_50, mwl8k_channels_50, sizeof(mwl8k_channels_50));

        BUILD_BUG_ON(sizeof(priv->rates_50) != sizeof(mwl8k_rates_50));
        memcpy(priv->rates_50, mwl8k_rates_50, sizeof(mwl8k_rates_50));

        priv->band_50.band = NL80211_BAND_5GHZ;
        priv->band_50.channels = priv->channels_50;
        priv->band_50.n_channels = ARRAY_SIZE(mwl8k_channels_50);
        priv->band_50.bitrates = priv->rates_50;
        priv->band_50.n_bitrates = ARRAY_SIZE(mwl8k_rates_50);

        hw->wiphy->bands[NL80211_BAND_5GHZ] = &priv->band_50;
}

/*
 * CMD_GET_HW_SPEC (STA version).
 */
struct mwl8k_cmd_get_hw_spec_sta {
        struct mwl8k_cmd_pkt header;
        __u8 hw_rev;
        __u8 host_interface;
        __le16 num_mcaddrs;
        __u8 perm_addr[ETH_ALEN];
        __le16 region_code;
        __le32 fw_rev;
        __le32 ps_cookie;
        __le32 caps;
        __u8 mcs_bitmap[16];
        __le32 rx_queue_ptr;
        __le32 num_tx_queues;
        __le32 tx_queue_ptrs[MWL8K_TX_WMM_QUEUES];
        __le32 caps2;
        __le32 num_tx_desc_per_queue;
        __le32 total_rxd;
} __packed;

#define MWL8K_CAP_MAX_AMSDU             0x20000000
#define MWL8K_CAP_GREENFIELD            0x08000000
#define MWL8K_CAP_AMPDU                 0x04000000
#define MWL8K_CAP_RX_STBC               0x01000000
#define MWL8K_CAP_TX_STBC               0x00800000
#define MWL8K_CAP_SHORTGI_40MHZ         0x00400000
#define MWL8K_CAP_SHORTGI_20MHZ         0x00200000
#define MWL8K_CAP_RX_ANTENNA_MASK       0x000e0000
#define MWL8K_CAP_TX_ANTENNA_MASK       0x0001c000
#define MWL8K_CAP_DELAY_BA              0x00003000
#define MWL8K_CAP_MIMO                  0x00000200
#define MWL8K_CAP_40MHZ                 0x00000100
#define MWL8K_CAP_BAND_MASK             0x00000007
#define MWL8K_CAP_5GHZ                  0x00000004
#define MWL8K_CAP_2GHZ4                 0x00000001

static void
mwl8k_set_ht_caps(struct ieee80211_hw *hw,
                  struct ieee80211_supported_band *band, u32 cap)
{
        int rx_streams;
        int tx_streams;

        band->ht_cap.ht_supported = 1;

        if (cap & MWL8K_CAP_MAX_AMSDU)
                band->ht_cap.cap |= IEEE80211_HT_CAP_MAX_AMSDU;
        if (cap & MWL8K_CAP_GREENFIELD)
                band->ht_cap.cap |= IEEE80211_HT_CAP_GRN_FLD;
        if (cap & MWL8K_CAP_AMPDU) {
                ieee80211_hw_set(hw, AMPDU_AGGREGATION);
                band->ht_cap.ampdu_factor = IEEE80211_HT_MAX_AMPDU_64K;
                band->ht_cap.ampdu_density = IEEE80211_HT_MPDU_DENSITY_NONE;
        }
        if (cap & MWL8K_CAP_RX_STBC)
                band->ht_cap.cap |= IEEE80211_HT_CAP_RX_STBC;
        if (cap & MWL8K_CAP_TX_STBC)
                band->ht_cap.cap |= IEEE80211_HT_CAP_TX_STBC;
        if (cap & MWL8K_CAP_SHORTGI_40MHZ)
                band->ht_cap.cap |= IEEE80211_HT_CAP_SGI_40;
        if (cap & MWL8K_CAP_SHORTGI_20MHZ)
                band->ht_cap.cap |= IEEE80211_HT_CAP_SGI_20;
        if (cap & MWL8K_CAP_DELAY_BA)
                band->ht_cap.cap |= IEEE80211_HT_CAP_DELAY_BA;
        if (cap & MWL8K_CAP_40MHZ)
                band->ht_cap.cap |= IEEE80211_HT_CAP_SUP_WIDTH_20_40;

        rx_streams = hweight32(cap & MWL8K_CAP_RX_ANTENNA_MASK);
        tx_streams = hweight32(cap & MWL8K_CAP_TX_ANTENNA_MASK);

        band->ht_cap.mcs.rx_mask[0] = 0xff;
        if (rx_streams >= 2)
                band->ht_cap.mcs.rx_mask[1] = 0xff;
        if (rx_streams >= 3)
                band->ht_cap.mcs.rx_mask[2] = 0xff;
        band->ht_cap.mcs.rx_mask[4] = 0x01;
        band->ht_cap.mcs.tx_params = IEEE80211_HT_MCS_TX_DEFINED;

        if (rx_streams != tx_streams) {
                band->ht_cap.mcs.tx_params |= IEEE80211_HT_MCS_TX_RX_DIFF;
                band->ht_cap.mcs.tx_params |= (tx_streams - 1) <<
                                IEEE80211_HT_MCS_TX_MAX_STREAMS_SHIFT;
        }
}

static void
mwl8k_set_caps(struct ieee80211_hw *hw, u32 caps)
{
        struct mwl8k_priv *priv = hw->priv;

        if (priv->caps)
                return;

        if ((caps & MWL8K_CAP_2GHZ4) || !(caps & MWL8K_CAP_BAND_MASK)) {
                mwl8k_setup_2ghz_band(hw);
                if (caps & MWL8K_CAP_MIMO)
                        mwl8k_set_ht_caps(hw, &priv->band_24, caps);
        }

        if (caps & MWL8K_CAP_5GHZ) {
                mwl8k_setup_5ghz_band(hw);
                if (caps & MWL8K_CAP_MIMO)
                        mwl8k_set_ht_caps(hw, &priv->band_50, caps);
        }

        priv->caps = caps;
}

static int mwl8k_cmd_get_hw_spec_sta(struct ieee80211_hw *hw)
{
        struct mwl8k_priv *priv = hw->priv;
        struct mwl8k_cmd_get_hw_spec_sta *cmd;
        int rc;
        int i;

        cmd = kzalloc(sizeof(*cmd), GFP_KERNEL);
        if (cmd == NULL)
                return -ENOMEM;

        cmd->header.code = cpu_to_le16(MWL8K_CMD_GET_HW_SPEC);
        cmd->header.length = cpu_to_le16(sizeof(*cmd));

        memset(cmd->perm_addr, 0xff, sizeof(cmd->perm_addr));
        cmd->ps_cookie = cpu_to_le32(priv->cookie_dma);
        cmd->rx_queue_ptr = cpu_to_le32(priv->rxq[0].rxd_dma);
        cmd->num_tx_queues = cpu_to_le32(mwl8k_tx_queues(priv));
        for (i = 0; i < mwl8k_tx_queues(priv); i++)
                cmd->tx_queue_ptrs[i] = cpu_to_le32(priv->txq[i].txd_dma);
        cmd->num_tx_desc_per_queue = cpu_to_le32(MWL8K_TX_DESCS);
        cmd->total_rxd = cpu_to_le32(MWL8K_RX_DESCS);

        rc = mwl8k_post_cmd(hw, &cmd->header);

        if (!rc) {
                SET_IEEE80211_PERM_ADDR(hw, cmd->perm_addr);
                priv->num_mcaddrs = le16_to_cpu(cmd->num_mcaddrs);
                priv->fw_rev = le32_to_cpu(cmd->fw_rev);
                priv->hw_rev = cmd->hw_rev;
                mwl8k_set_caps(hw, le32_to_cpu(cmd->caps));
                priv->ap_macids_supported = 0x00000000;
                priv->sta_macids_supported = 0x00000001;
        }

        kfree(cmd);
        return rc;
}

/*
 * CMD_GET_HW_SPEC (AP version).
 */
struct mwl8k_cmd_get_hw_spec_ap {
        struct mwl8k_cmd_pkt header;
        __u8 hw_rev;
        __u8 host_interface;
        __le16 num_wcb;
        __le16 num_mcaddrs;
        __u8 perm_addr[ETH_ALEN];
        __le16 region_code;
        __le16 num_antenna;
        __le32 fw_rev;
        __le32 wcbbase0;
        __le32 rxwrptr;
        __le32 rxrdptr;
        __le32 ps_cookie;
        __le32 wcbbase1;
        __le32 wcbbase2;
        __le32 wcbbase3;
        __le32 fw_api_version;
        __le32 caps;
        __le32 num_of_ampdu_queues;
        __le32 wcbbase_ampdu[MWL8K_MAX_AMPDU_QUEUES];
} __packed;

static int mwl8k_cmd_get_hw_spec_ap(struct ieee80211_hw *hw)
{
        struct mwl8k_priv *priv = hw->priv;
        struct mwl8k_cmd_get_hw_spec_ap *cmd;
        int rc, i;
        u32 api_version;

        cmd = kzalloc(sizeof(*cmd), GFP_KERNEL);
        if (cmd == NULL)
                return -ENOMEM;

        cmd->header.code = cpu_to_le16(MWL8K_CMD_GET_HW_SPEC);
        cmd->header.length = cpu_to_le16(sizeof(*cmd));

        memset(cmd->perm_addr, 0xff, sizeof(cmd->perm_addr));
        cmd->ps_cookie = cpu_to_le32(priv->cookie_dma);

        rc = mwl8k_post_cmd(hw, &cmd->header);

        if (!rc) {
                int off;

                api_version = le32_to_cpu(cmd->fw_api_version);
                if (priv->device_info->fw_api_ap != api_version) {
                        printk(KERN_ERR "%s: Unsupported fw API version for %s."
                               "  Expected %d got %d.\n", MWL8K_NAME,
                               priv->device_info->part_name,
                               priv->device_info->fw_api_ap,
                               api_version);
                        rc = -EINVAL;
                        goto done;
                }
                SET_IEEE80211_PERM_ADDR(hw, cmd->perm_addr);
                priv->num_mcaddrs = le16_to_cpu(cmd->num_mcaddrs);
                priv->fw_rev = le32_to_cpu(cmd->fw_rev);
                priv->hw_rev = cmd->hw_rev;
                mwl8k_set_caps(hw, le32_to_cpu(cmd->caps));
                priv->ap_macids_supported = 0x000000ff;
                priv->sta_macids_supported = 0x00000100;
                priv->num_ampdu_queues = le32_to_cpu(cmd->num_of_ampdu_queues);
                if (priv->num_ampdu_queues > MWL8K_MAX_AMPDU_QUEUES) {
                        wiphy_warn(hw->wiphy, "fw reported %d ampdu queues"
                                   " but we only support %d.\n",
                                   priv->num_ampdu_queues,
                                   MWL8K_MAX_AMPDU_QUEUES);
                        priv->num_ampdu_queues = MWL8K_MAX_AMPDU_QUEUES;
                }
                off = le32_to_cpu(cmd->rxwrptr) & 0xffff;
                iowrite32(priv->rxq[0].rxd_dma, priv->sram + off);

                off = le32_to_cpu(cmd->rxrdptr) & 0xffff;
                iowrite32(priv->rxq[0].rxd_dma, priv->sram + off);

                priv->txq_offset[0] = le32_to_cpu(cmd->wcbbase0) & 0xffff;
                priv->txq_offset[1] = le32_to_cpu(cmd->wcbbase1) & 0xffff;
                priv->txq_offset[2] = le32_to_cpu(cmd->wcbbase2) & 0xffff;
                priv->txq_offset[3] = le32_to_cpu(cmd->wcbbase3) & 0xffff;

                for (i = 0; i < priv->num_ampdu_queues; i++)
                        priv->txq_offset[i + MWL8K_TX_WMM_QUEUES] =
                                le32_to_cpu(cmd->wcbbase_ampdu[i]) & 0xffff;
        }

done:
        kfree(cmd);
        return rc;
}

/*
 * CMD_SET_HW_SPEC.
 */
struct mwl8k_cmd_set_hw_spec {
        struct mwl8k_cmd_pkt header;
        __u8 hw_rev;
        __u8 host_interface;
        __le16 num_mcaddrs;
        __u8 perm_addr[ETH_ALEN];
        __le16 region_code;
        __le32 fw_rev;
        __le32 ps_cookie;
        __le32 caps;
        __le32 rx_queue_ptr;
        __le32 num_tx_queues;
        __le32 tx_queue_ptrs[MWL8K_MAX_TX_QUEUES];
        __le32 flags;
        __le32 num_tx_desc_per_queue;
        __le32 total_rxd;
} __packed;

/* If enabled, MWL8K_SET_HW_SPEC_FLAG_ENABLE_LIFE_TIME_EXPIRY will cause
 * packets to expire 500 ms after the timestamp in the tx descriptor.  That is,
 * the packets that are queued for more than 500ms, will be dropped in the
 * hardware. This helps minimizing the issues caused due to head-of-line
 * blocking where a slow client can hog the bandwidth and affect traffic to a
 * faster client.
 */
#define MWL8K_SET_HW_SPEC_FLAG_ENABLE_LIFE_TIME_EXPIRY  0x00000400
#define MWL8K_SET_HW_SPEC_FLAG_GENERATE_CCMP_HDR        0x00000200
#define MWL8K_SET_HW_SPEC_FLAG_HOST_DECR_MGMT           0x00000080
#define MWL8K_SET_HW_SPEC_FLAG_HOSTFORM_PROBERESP       0x00000020
#define MWL8K_SET_HW_SPEC_FLAG_HOSTFORM_BEACON          0x00000010

static int mwl8k_cmd_set_hw_spec(struct ieee80211_hw *hw)
{
        struct mwl8k_priv *priv = hw->priv;
        struct mwl8k_cmd_set_hw_spec *cmd;
        int rc;
        int i;

        cmd = kzalloc(sizeof(*cmd), GFP_KERNEL);
        if (cmd == NULL)
                return -ENOMEM;

        cmd->header.code = cpu_to_le16(MWL8K_CMD_SET_HW_SPEC);
        cmd->header.length = cpu_to_le16(sizeof(*cmd));

        cmd->ps_cookie = cpu_to_le32(priv->cookie_dma);
        cmd->rx_queue_ptr = cpu_to_le32(priv->rxq[0].rxd_dma);
        cmd->num_tx_queues = cpu_to_le32(mwl8k_tx_queues(priv));

        /*
         * Mac80211 stack has Q0 as highest priority and Q3 as lowest in
         * that order. Firmware has Q3 as highest priority and Q0 as lowest
         * in that order. Map Q3 of mac80211 to Q0 of firmware so that the
         * priority is interpreted the right way in firmware.
         */
        for (i = 0; i < mwl8k_tx_queues(priv); i++) {
                int j = mwl8k_tx_queues(priv) - 1 - i;
                cmd->tx_queue_ptrs[i] = cpu_to_le32(priv->txq[j].txd_dma);
        }

        cmd->flags = cpu_to_le32(MWL8K_SET_HW_SPEC_FLAG_HOST_DECR_MGMT |
                                 MWL8K_SET_HW_SPEC_FLAG_HOSTFORM_PROBERESP |
                                 MWL8K_SET_HW_SPEC_FLAG_HOSTFORM_BEACON |
                                 MWL8K_SET_HW_SPEC_FLAG_ENABLE_LIFE_TIME_EXPIRY |
                                 MWL8K_SET_HW_SPEC_FLAG_GENERATE_CCMP_HDR);
        cmd->num_tx_desc_per_queue = cpu_to_le32(MWL8K_TX_DESCS);
        cmd->total_rxd = cpu_to_le32(MWL8K_RX_DESCS);

        rc = mwl8k_post_cmd(hw, &cmd->header);
        kfree(cmd);

        return rc;
}

/*
 * CMD_MAC_MULTICAST_ADR.
 */
struct mwl8k_cmd_mac_multicast_adr {
        struct mwl8k_cmd_pkt header;
        __le16 action;
        __le16 numaddr;
        __u8 addr[][ETH_ALEN];
};

#define MWL8K_ENABLE_RX_DIRECTED        0x0001
#define MWL8K_ENABLE_RX_MULTICAST       0x0002
#define MWL8K_ENABLE_RX_ALL_MULTICAST   0x0004
#define MWL8K_ENABLE_RX_BROADCAST       0x0008

static struct mwl8k_cmd_pkt *
__mwl8k_cmd_mac_multicast_adr(struct ieee80211_hw *hw, int allmulti,
                              struct netdev_hw_addr_list *mc_list)
{
        struct mwl8k_priv *priv = hw->priv;
        struct mwl8k_cmd_mac_multicast_adr *cmd;
        int size;
        int mc_count = 0;

        if (mc_list)
                mc_count = netdev_hw_addr_list_count(mc_list);

        if (allmulti || mc_count > priv->num_mcaddrs) {
                allmulti = 1;
                mc_count = 0;
        }

        size = sizeof(*cmd) + mc_count * ETH_ALEN;

        cmd = kzalloc(size, GFP_ATOMIC);
        if (cmd == NULL)
                return NULL;

        cmd->header.code = cpu_to_le16(MWL8K_CMD_MAC_MULTICAST_ADR);
        cmd->header.length = cpu_to_le16(size);
        cmd->action = cpu_to_le16(MWL8K_ENABLE_RX_DIRECTED |
                                  MWL8K_ENABLE_RX_BROADCAST);

        if (allmulti) {
                cmd->action |= cpu_to_le16(MWL8K_ENABLE_RX_ALL_MULTICAST);
        } else if (mc_count) {
                struct netdev_hw_addr *ha;
                int i = 0;

                cmd->action |= cpu_to_le16(MWL8K_ENABLE_RX_MULTICAST);
                cmd->numaddr = cpu_to_le16(mc_count);
                netdev_hw_addr_list_for_each(ha, mc_list) {
                        memcpy(cmd->addr[i], ha->addr, ETH_ALEN);
                }
        }

        return &cmd->header;
}

/*
 * CMD_GET_STAT.
 */
struct mwl8k_cmd_get_stat {
        struct mwl8k_cmd_pkt header;
        __le32 stats[64];
} __packed;

#define MWL8K_STAT_ACK_FAILURE  9
#define MWL8K_STAT_RTS_FAILURE  12
#define MWL8K_STAT_FCS_ERROR    24
#define MWL8K_STAT_RTS_SUCCESS  11

static int mwl8k_cmd_get_stat(struct ieee80211_hw *hw,
                              struct ieee80211_low_level_stats *stats)
{
        struct mwl8k_cmd_get_stat *cmd;
        int rc;

        cmd = kzalloc(sizeof(*cmd), GFP_KERNEL);
        if (cmd == NULL)
                return -ENOMEM;

        cmd->header.code = cpu_to_le16(MWL8K_CMD_GET_STAT);
        cmd->header.length = cpu_to_le16(sizeof(*cmd));

        rc = mwl8k_post_cmd(hw, &cmd->header);
        if (!rc) {
                stats->dot11ACKFailureCount =
                        le32_to_cpu(cmd->stats[MWL8K_STAT_ACK_FAILURE]);
                stats->dot11RTSFailureCount =
                        le32_to_cpu(cmd->stats[MWL8K_STAT_RTS_FAILURE]);
                stats->dot11FCSErrorCount =
                        le32_to_cpu(cmd->stats[MWL8K_STAT_FCS_ERROR]);
                stats->dot11RTSSuccessCount =
                        le32_to_cpu(cmd->stats[MWL8K_STAT_RTS_SUCCESS]);
        }
        kfree(cmd);

        return rc;
}

/*
 * CMD_RADIO_CONTROL.
 */
struct mwl8k_cmd_radio_control {
        struct mwl8k_cmd_pkt header;
        __le16 action;
        __le16 control;
        __le16 radio_on;
} __packed;

static int
mwl8k_cmd_radio_control(struct ieee80211_hw *hw, bool enable, bool force)
{
        struct mwl8k_priv *priv = hw->priv;
        struct mwl8k_cmd_radio_control *cmd;
        int rc;

        if (enable == priv->radio_on && !force)
                return 0;

        cmd = kzalloc(sizeof(*cmd), GFP_KERNEL);
        if (cmd == NULL)
                return -ENOMEM;

        cmd->header.code = cpu_to_le16(MWL8K_CMD_RADIO_CONTROL);
        cmd->header.length = cpu_to_le16(sizeof(*cmd));
        cmd->action = cpu_to_le16(MWL8K_CMD_SET);
        cmd->control = cpu_to_le16(priv->radio_short_preamble ? 3 : 1);
        cmd->radio_on = cpu_to_le16(enable ? 0x0001 : 0x0000);

        rc = mwl8k_post_cmd(hw, &cmd->header);
        kfree(cmd);

        if (!rc)
                priv->radio_on = enable;

        return rc;
}

static int mwl8k_cmd_radio_disable(struct ieee80211_hw *hw)
{
        return mwl8k_cmd_radio_control(hw, 0, 0);
}

static int mwl8k_cmd_radio_enable(struct ieee80211_hw *hw)
{
        return mwl8k_cmd_radio_control(hw, 1, 0);
}

static int
mwl8k_set_radio_preamble(struct ieee80211_hw *hw, bool short_preamble)
{
        struct mwl8k_priv *priv = hw->priv;

        priv->radio_short_preamble = short_preamble;

        return mwl8k_cmd_radio_control(hw, 1, 1);
}

/*
 * CMD_RF_TX_POWER.
 */
#define MWL8K_RF_TX_POWER_LEVEL_TOTAL   8

struct mwl8k_cmd_rf_tx_power {
        struct mwl8k_cmd_pkt header;
        __le16 action;
        __le16 support_level;
        __le16 current_level;
        __le16 reserved;
        __le16 power_level_list[MWL8K_RF_TX_POWER_LEVEL_TOTAL];
} __packed;

static int mwl8k_cmd_rf_tx_power(struct ieee80211_hw *hw, int dBm)
{
        struct mwl8k_cmd_rf_tx_power *cmd;
        int rc;

        cmd = kzalloc(sizeof(*cmd), GFP_KERNEL);
        if (cmd == NULL)
                return -ENOMEM;

        cmd->header.code = cpu_to_le16(MWL8K_CMD_RF_TX_POWER);
        cmd->header.length = cpu_to_le16(sizeof(*cmd));
        cmd->action = cpu_to_le16(MWL8K_CMD_SET);
        cmd->support_level = cpu_to_le16(dBm);

        rc = mwl8k_post_cmd(hw, &cmd->header);
        kfree(cmd);

        return rc;
}

/*
 * CMD_TX_POWER.
 */
#define MWL8K_TX_POWER_LEVEL_TOTAL      12

struct mwl8k_cmd_tx_power {
        struct mwl8k_cmd_pkt header;
        __le16 action;
        __le16 band;
        __le16 channel;
        __le16 bw;
        __le16 sub_ch;
        __le16 power_level_list[MWL8K_TX_POWER_LEVEL_TOTAL];
} __packed;

static int mwl8k_cmd_tx_power(struct ieee80211_hw *hw,
                                     struct ieee80211_conf *conf,
                                     unsigned short pwr)
{
        struct ieee80211_channel *channel = conf->chandef.chan;
        enum nl80211_channel_type channel_type =
                cfg80211_get_chandef_type(&conf->chandef);
        struct mwl8k_cmd_tx_power *cmd;
        int rc;
        int i;

        cmd = kzalloc(sizeof(*cmd), GFP_KERNEL);
        if (cmd == NULL)
                return -ENOMEM;

        cmd->header.code = cpu_to_le16(MWL8K_CMD_TX_POWER);
        cmd->header.length = cpu_to_le16(sizeof(*cmd));
        cmd->action = cpu_to_le16(MWL8K_CMD_SET_LIST);

        if (channel->band == NL80211_BAND_2GHZ)
                cmd->band = cpu_to_le16(0x1);
        else if (channel->band == NL80211_BAND_5GHZ)
                cmd->band = cpu_to_le16(0x4);

        cmd->channel = cpu_to_le16(channel->hw_value);

        if (channel_type == NL80211_CHAN_NO_HT ||
            channel_type == NL80211_CHAN_HT20) {
                cmd->bw = cpu_to_le16(0x2);
        } else {
                cmd->bw = cpu_to_le16(0x4);
                if (channel_type == NL80211_CHAN_HT40MINUS)
                        cmd->sub_ch = cpu_to_le16(0x3);
                else if (channel_type == NL80211_CHAN_HT40PLUS)
                        cmd->sub_ch = cpu_to_le16(0x1);
        }

        for (i = 0; i < MWL8K_TX_POWER_LEVEL_TOTAL; i++)
                cmd->power_level_list[i] = cpu_to_le16(pwr);

        rc = mwl8k_post_cmd(hw, &cmd->header);
        kfree(cmd);

        return rc;
}

/*
 * CMD_RF_ANTENNA.
 */
struct mwl8k_cmd_rf_antenna {
        struct mwl8k_cmd_pkt header;
        __le16 antenna;
        __le16 mode;
} __packed;

#define MWL8K_RF_ANTENNA_RX             1
#define MWL8K_RF_ANTENNA_TX             2

static int
mwl8k_cmd_rf_antenna(struct ieee80211_hw *hw, int antenna, int mask)
{
        struct mwl8k_cmd_rf_antenna *cmd;
        int rc;

        cmd = kzalloc(sizeof(*cmd), GFP_KERNEL);
        if (cmd == NULL)
                return -ENOMEM;

        cmd->header.code = cpu_to_le16(MWL8K_CMD_RF_ANTENNA);
        cmd->header.length = cpu_to_le16(sizeof(*cmd));
        cmd->antenna = cpu_to_le16(antenna);
        cmd->mode = cpu_to_le16(mask);

        rc = mwl8k_post_cmd(hw, &cmd->header);
        kfree(cmd);

        return rc;
}

/*
 * CMD_SET_BEACON.
 */
struct mwl8k_cmd_set_beacon {
        struct mwl8k_cmd_pkt header;
        __le16 beacon_len;
        __u8 beacon[];
};

static int mwl8k_cmd_set_beacon(struct ieee80211_hw *hw,
                                struct ieee80211_vif *vif, u8 *beacon, int len)
{
        struct mwl8k_cmd_set_beacon *cmd;
        int rc;

        cmd = kzalloc(sizeof(*cmd) + len, GFP_KERNEL);
        if (cmd == NULL)
                return -ENOMEM;

        cmd->header.code = cpu_to_le16(MWL8K_CMD_SET_BEACON);
        cmd->header.length = cpu_to_le16(sizeof(*cmd) + len);
        cmd->beacon_len = cpu_to_le16(len);
        memcpy(cmd->beacon, beacon, len);

        rc = mwl8k_post_pervif_cmd(hw, vif, &cmd->header);
        kfree(cmd);

        return rc;
}

/*
 * CMD_SET_PRE_SCAN.
 */
struct mwl8k_cmd_set_pre_scan {
        struct mwl8k_cmd_pkt header;
} __packed;

static int mwl8k_cmd_set_pre_scan(struct ieee80211_hw *hw)
{
        struct mwl8k_cmd_set_pre_scan *cmd;
        int rc;

        cmd = kzalloc(sizeof(*cmd), GFP_KERNEL);
        if (cmd == NULL)