// SPDX-License-Identifier: GPL-2.0-only
/*
 * Copyright (c) 2021 pureLiFi
 */

#include <linux/netdevice.h>
#include <linux/etherdevice.h>
#include <linux/slab.h>
#include <linux/usb.h>
#include <linux/jiffies.h>
#include <net/ieee80211_radiotap.h>

#include "chip.h"
#include "mac.h"
#include "usb.h"

static const struct ieee80211_rate plfxlc_rates[] = {
        { .bitrate = 10,
                .hw_value = PURELIFI_CCK_RATE_1M,
                .flags = 0 },
        { .bitrate = 20,
                .hw_value = PURELIFI_CCK_RATE_2M,
                .hw_value_short = PURELIFI_CCK_RATE_2M
                        | PURELIFI_CCK_PREA_SHORT,
                .flags = IEEE80211_RATE_SHORT_PREAMBLE },
        { .bitrate = 55,
                .hw_value = PURELIFI_CCK_RATE_5_5M,
                .hw_value_short = PURELIFI_CCK_RATE_5_5M
                        | PURELIFI_CCK_PREA_SHORT,
                .flags = IEEE80211_RATE_SHORT_PREAMBLE },
        { .bitrate = 110,
                .hw_value = PURELIFI_CCK_RATE_11M,
                .hw_value_short = PURELIFI_CCK_RATE_11M
                        | PURELIFI_CCK_PREA_SHORT,
                .flags = IEEE80211_RATE_SHORT_PREAMBLE },
        { .bitrate = 60,
                .hw_value = PURELIFI_OFDM_RATE_6M,
                .flags = 0 },
        { .bitrate = 90,
                .hw_value = PURELIFI_OFDM_RATE_9M,
                .flags = 0 },
        { .bitrate = 120,
                .hw_value = PURELIFI_OFDM_RATE_12M,
                .flags = 0 },
        { .bitrate = 180,
                .hw_value = PURELIFI_OFDM_RATE_18M,
                .flags = 0 },
        { .bitrate = 240,
                .hw_value = PURELIFI_OFDM_RATE_24M,
                .flags = 0 },
        { .bitrate = 360,
                .hw_value = PURELIFI_OFDM_RATE_36M,
                .flags = 0 },
        { .bitrate = 480,
                .hw_value = PURELIFI_OFDM_RATE_48M,
                .flags = 0 },
        { .bitrate = 540,
                .hw_value = PURELIFI_OFDM_RATE_54M,
                .flags = 0 }
};

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

int plfxlc_mac_preinit_hw(struct ieee80211_hw *hw, const u8 *hw_address)
{
        SET_IEEE80211_PERM_ADDR(hw, hw_address);
        return 0;
}

int plfxlc_mac_init_hw(struct ieee80211_hw *hw)
{
        struct plfxlc_mac *mac = plfxlc_hw_mac(hw);
        struct plfxlc_chip *chip = &mac->chip;
        int r;

        r = plfxlc_chip_init_hw(chip);
        if (r) {
                dev_warn(plfxlc_mac_dev(mac), "init hw failed (%d)\n", r);
                return r;
        }

        dev_dbg(plfxlc_mac_dev(mac), "irq_disabled (%d)\n", irqs_disabled());
        regulatory_hint(hw->wiphy, "00");
        return r;
}

int plfxlc_op_start(struct ieee80211_hw *hw)
{
        plfxlc_hw_mac(hw)->chip.usb.initialized = 1;
        return 0;
}

void plfxlc_op_stop(struct ieee80211_hw *hw, bool suspend)
{
        struct plfxlc_mac *mac = plfxlc_hw_mac(hw);

        clear_bit(PURELIFI_DEVICE_RUNNING, &mac->flags);
}

int plfxlc_restore_settings(struct plfxlc_mac *mac)
{
        int beacon_interval, beacon_period;
        struct sk_buff *beacon;

        spin_lock_irq(&mac->lock);
        beacon_interval = mac->beacon.interval;
        beacon_period = mac->beacon.period;
        spin_unlock_irq(&mac->lock);

        if (mac->type != NL80211_IFTYPE_ADHOC)
                return 0;

        if (mac->vif) {
                beacon = ieee80211_beacon_get(mac->hw, mac->vif, 0);
                if (beacon) {
                        /*beacon is hardcoded in firmware */
                        kfree_skb(beacon);
                        /* Returned skb is used only once and lowlevel
                         * driver is responsible for freeing it.
                         */
                }
        }

        plfxlc_set_beacon_interval(&mac->chip, beacon_interval,
                                   beacon_period, mac->type);

        spin_lock_irq(&mac->lock);
        mac->beacon.last_update = jiffies;
        spin_unlock_irq(&mac->lock);

        return 0;
}

static void plfxlc_mac_tx_status(struct ieee80211_hw *hw,
                                 struct sk_buff *skb,
                                 int ackssi,
                                 struct tx_status *tx_status)
{
        struct ieee80211_tx_info *info = IEEE80211_SKB_CB(skb);
        int success = 1;

        ieee80211_tx_info_clear_status(info);
        if (tx_status)
                success = !tx_status->failure;

        if (success)
                info->flags |= IEEE80211_TX_STAT_ACK;
        else
                info->flags &= ~IEEE80211_TX_STAT_ACK;

        info->status.ack_signal = 50;
        ieee80211_tx_status_irqsafe(hw, skb);
}

void plfxlc_mac_tx_to_dev(struct sk_buff *skb, int error)
{
        struct ieee80211_tx_info *info = IEEE80211_SKB_CB(skb);
        struct ieee80211_hw *hw = info->rate_driver_data[0];
        struct plfxlc_mac *mac = plfxlc_hw_mac(hw);
        struct sk_buff_head *q = NULL;

        ieee80211_tx_info_clear_status(info);
        skb_pull(skb, sizeof(struct plfxlc_ctrlset));

        if (unlikely(error ||
                     (info->flags & IEEE80211_TX_CTL_NO_ACK))) {
                ieee80211_tx_status_irqsafe(hw, skb);
                return;
        }

        q = &mac->ack_wait_queue;

        skb_queue_tail(q, skb);
        while (skb_queue_len(q)/* > PURELIFI_MAC_MAX_ACK_WAITERS*/) {
                plfxlc_mac_tx_status(hw, skb_dequeue(q),
                                     mac->ack_pending ?
                                     mac->ack_signal : 0,
                                     NULL);
                mac->ack_pending = 0;
        }
}

static int plfxlc_fill_ctrlset(struct plfxlc_mac *mac, struct sk_buff *skb)
{
        unsigned int frag_len = skb->len;
        struct plfxlc_ctrlset *cs;
        u32 temp_payload_len = 0;
        unsigned int tmp;
        u32 temp_len = 0;

        if (skb_headroom(skb) < sizeof(struct plfxlc_ctrlset)) {
                dev_dbg(plfxlc_mac_dev(mac), "Not enough hroom(1)\n");
                return 1;
        }

        cs = (void *)skb_push(skb, sizeof(struct plfxlc_ctrlset));
        temp_payload_len = frag_len;
        temp_len = temp_payload_len +
                  sizeof(struct plfxlc_ctrlset) -
                  sizeof(cs->id) - sizeof(cs->len);

        /* Data packet lengths must be multiple of four bytes and must
         * not be a multiple of 512 bytes. First, it is attempted to
         * append the data packet in the tailroom of the skb. In rare
         * occasions, the tailroom is too small. In this case, the
         * content of the packet is shifted into the headroom of the skb
         * by memcpy. Headroom is allocated at startup (below in this
         * file). Therefore, there will be always enough headroom. The
         * call skb_headroom is an additional safety which might be
         * dropped.
         */
        /* check if 32 bit aligned and align data */
        tmp = skb->len & 3;
        if (tmp) {
                if (skb_tailroom(skb) < (3 - tmp)) {
                        if (skb_headroom(skb) >= 4 - tmp) {
                                u8 len;
                                u8 *src_pt;
                                u8 *dest_pt;

                                len = skb->len;
                                src_pt = skb->data;
                                dest_pt = skb_push(skb, 4 - tmp);
                                memmove(dest_pt, src_pt, len);
                        } else {
                                return -ENOBUFS;
                        }
                } else {
                        skb_put(skb, 4 - tmp);
                }
                temp_len += 4 - tmp;
        }

        /* check if not multiple of 512 and align data */
        tmp = skb->len & 0x1ff;
        if (!tmp) {
                if (skb_tailroom(skb) < 4) {
                        if (skb_headroom(skb) >= 4) {
                                u8 len = skb->len;
                                u8 *src_pt = skb->data;
                                u8 *dest_pt = skb_push(skb, 4);

                                memmove(dest_pt, src_pt, len);
                        } else {
                                /* should never happen because
                                 * sufficient headroom was reserved
                                 */
                                return -ENOBUFS;
                        }
                } else {
                        skb_put(skb, 4);
                }
                temp_len += 4;
        }

        cs->id = cpu_to_be32(USB_REQ_DATA_TX);
        cs->len = cpu_to_be32(temp_len);
        cs->payload_len_nw = cpu_to_be32(temp_payload_len);

        return 0;
}

static void plfxlc_op_tx(struct ieee80211_hw *hw,
                         struct ieee80211_tx_control *control,
                         struct sk_buff *skb)
{
        struct ieee80211_tx_info *info = IEEE80211_SKB_CB(skb);
        struct plfxlc_header *plhdr = (void *)skb->data;
        struct plfxlc_mac *mac = plfxlc_hw_mac(hw);
        struct plfxlc_usb *usb = &mac->chip.usb;
        unsigned long flags;
        int r;

        r = plfxlc_fill_ctrlset(mac, skb);
        if (r)
                goto fail;

        info->rate_driver_data[0] = hw;

        if (plhdr->frametype  == IEEE80211_FTYPE_DATA) {
                u8 *dst_mac = plhdr->dmac;
                u8 sidx;
                bool found = false;
                struct plfxlc_usb_tx *tx = &usb->tx;

                for (sidx = 0; sidx < MAX_STA_NUM; sidx++) {
                        if (!(tx->station[sidx].flag & STATION_CONNECTED_FLAG))
                                continue;
                        if (memcmp(tx->station[sidx].mac, dst_mac, ETH_ALEN))
                                continue;
                        found = true;
                        break;
                }

                /* Default to broadcast address for unknown MACs */
                if (!found)
                        sidx = STA_BROADCAST_INDEX;

                /* Stop OS from sending packets, if the queue is half full */
                if (skb_queue_len(&tx->station[sidx].data_list) > 60)
                        ieee80211_stop_queues(plfxlc_usb_to_hw(usb));

                /* Schedule packet for transmission if queue is not full */
                if (skb_queue_len(&tx->station[sidx].data_list) > 256)
                        goto fail;
                skb_queue_tail(&tx->station[sidx].data_list, skb);
                plfxlc_send_packet_from_data_queue(usb);

        } else {
                spin_lock_irqsave(&usb->tx.lock, flags);
                r = plfxlc_usb_wreq_async(&mac->chip.usb, skb->data, skb->len,
                                          USB_REQ_DATA_TX, plfxlc_tx_urb_complete, skb);
                spin_unlock_irqrestore(&usb->tx.lock, flags);
                if (r)
                        goto fail;
        }
        return;

fail:
        dev_kfree_skb(skb);
}

static int plfxlc_filter_ack(struct ieee80211_hw *hw, struct ieee80211_hdr *rx_hdr,
                             struct ieee80211_rx_status *stats)
{
        struct plfxlc_mac *mac = plfxlc_hw_mac(hw);
        struct sk_buff_head *q;
        int i, position = 0;
        unsigned long flags;
        struct sk_buff *skb;
        bool found = false;

        if (!ieee80211_is_ack(rx_hdr->frame_control))
                return 0;

        dev_dbg(plfxlc_mac_dev(mac), "ACK Received\n");

        /* code based on zy driver, this logic may need fix */
        q = &mac->ack_wait_queue;
        spin_lock_irqsave(&q->lock, flags);

        skb_queue_walk(q, skb) {
                struct ieee80211_hdr *tx_hdr;

                position++;

                if (mac->ack_pending && skb_queue_is_first(q, skb))
                        continue;
                if (mac->ack_pending == 0)
                        break;

                tx_hdr = (struct ieee80211_hdr *)skb->data;
                if (likely(ether_addr_equal(tx_hdr->addr2, rx_hdr->addr1))) {
                        found = 1;
                        break;
                }
        }

        if (found) {
                for (i = 1; i < position; i++)
                        skb = __skb_dequeue(q);
                if (i == position) {
                        plfxlc_mac_tx_status(hw, skb,
                                             mac->ack_pending ?
                                             mac->ack_signal : 0,
                                             NULL);
                        mac->ack_pending = 0;
                }

                mac->ack_pending = skb_queue_len(q) ? 1 : 0;
                mac->ack_signal = stats->signal;
        }

        spin_unlock_irqrestore(&q->lock, flags);
        return 1;
}

int plfxlc_mac_rx(struct ieee80211_hw *hw, const u8 *buffer,
                  unsigned int length)
{
        struct plfxlc_mac *mac = plfxlc_hw_mac(hw);
        struct ieee80211_rx_status stats;
        const struct rx_status *status;
        unsigned int payload_length;
        struct plfxlc_usb_tx *tx;
        struct sk_buff *skb;
        int need_padding;
        __le16 fc;
        int sidx;

        /* Packet blockade during disabled interface. */
        if (!mac->vif)
                return 0;

        status = (struct rx_status *)buffer;

        memset(&stats, 0, sizeof(stats));

        stats.flag     = 0;
        stats.freq     = 2412;
        stats.band     = NL80211_BAND_LC;
        mac->rssi      = -15 * be16_to_cpu(status->rssi) / 10;

        stats.signal   = mac->rssi;

        if (status->rate_idx > 7)
                stats.rate_idx = 0;
        else
                stats.rate_idx = status->rate_idx;

        mac->crc_errors = be64_to_cpu(status->crc_error_count);

        /* TODO bad frame check for CRC error*/
        if (plfxlc_filter_ack(hw, (struct ieee80211_hdr *)buffer, &stats) &&
            !mac->pass_ctrl)
                return 0;

        buffer += sizeof(struct rx_status);
        payload_length = get_unaligned_be32(buffer);

        if (payload_length > 1560) {
                dev_err(plfxlc_mac_dev(mac), " > MTU %u\n", payload_length);
                return 0;
        }
        buffer += sizeof(u32);

        fc = get_unaligned((__le16 *)buffer);
        need_padding = ieee80211_is_data_qos(fc) ^ ieee80211_has_a4(fc);

        tx = &mac->chip.usb.tx;

        for (sidx = 0; sidx < MAX_STA_NUM - 1; sidx++) {
                if (memcmp(&buffer[10], tx->station[sidx].mac, ETH_ALEN))
                        continue;
                if (tx->station[sidx].flag & STATION_CONNECTED_FLAG) {
                        tx->station[sidx].flag |= STATION_HEARTBEAT_FLAG;
                        break;
                }
        }

        if (sidx == MAX_STA_NUM - 1) {
                for (sidx = 0; sidx < MAX_STA_NUM - 1; sidx++) {
                        if (tx->station[sidx].flag & STATION_CONNECTED_FLAG)
                                continue;
                        memcpy(tx->station[sidx].mac, &buffer[10], ETH_ALEN);
                        tx->station[sidx].flag |= STATION_CONNECTED_FLAG;
                        tx->station[sidx].flag |= STATION_HEARTBEAT_FLAG;
                        break;
                }
        }

        switch (buffer[0]) {
        case IEEE80211_STYPE_PROBE_REQ:
                dev_dbg(plfxlc_mac_dev(mac), "Probe request\n");
                break;
        case IEEE80211_STYPE_ASSOC_REQ:
                dev_dbg(plfxlc_mac_dev(mac), "Association request\n");
                break;
        case IEEE80211_STYPE_AUTH:
                dev_dbg(plfxlc_mac_dev(mac), "Authentication req\n");
                break;
        case IEEE80211_FTYPE_DATA:
                dev_dbg(plfxlc_mac_dev(mac), "802.11 data frame\n");
                break;
        }

        skb = dev_alloc_skb(payload_length + (need_padding ? 2 : 0));
        if (!skb)
                return -ENOMEM;

        if (need_padding)
                /* Make sure that the payload data is 4 byte aligned. */
                skb_reserve(skb, 2);

        skb_put_data(skb, buffer, payload_length);
        memcpy(IEEE80211_SKB_RXCB(skb), &stats, sizeof(stats));
        ieee80211_rx_irqsafe(hw, skb);
        return 0;
}

static int plfxlc_op_add_interface(struct ieee80211_hw *hw,
                                   struct ieee80211_vif *vif)
{
        struct plfxlc_mac *mac = plfxlc_hw_mac(hw);
        static const char * const iftype80211[] = {
                [NL80211_IFTYPE_STATION]        = "Station",
                [NL80211_IFTYPE_ADHOC]          = "Adhoc"
        };

        if (mac->type != NL80211_IFTYPE_UNSPECIFIED)
                return -EOPNOTSUPP;

        if (vif->type == NL80211_IFTYPE_ADHOC ||
            vif->type == NL80211_IFTYPE_STATION) {
                dev_dbg(plfxlc_mac_dev(mac), "%s %s\n", __func__,
                        iftype80211[vif->type]);
                mac->type = vif->type;
                mac->vif = vif;
                return 0;
        }
        dev_dbg(plfxlc_mac_dev(mac), "unsupported iftype\n");
        return -EOPNOTSUPP;
}

static void plfxlc_op_remove_interface(struct ieee80211_hw *hw,
                                       struct ieee80211_vif *vif)
{
        struct plfxlc_mac *mac = plfxlc_hw_mac(hw);

        mac->type = NL80211_IFTYPE_UNSPECIFIED;
        mac->vif = NULL;
}

static int plfxlc_op_config(struct ieee80211_hw *hw, int radio_idx, u32 changed)
{
        return 0;
}

#define SUPPORTED_FIF_FLAGS \
        (FIF_ALLMULTI | FIF_FCSFAIL | FIF_CONTROL | \
         FIF_OTHER_BSS | FIF_BCN_PRBRESP_PROMISC)
static void plfxlc_op_configure_filter(struct ieee80211_hw *hw,
                                       unsigned int changed_flags,
                                       unsigned int *new_flags,
                                       u64 multicast)
{
        struct plfxlc_mc_hash hash = {
                .low = multicast,
                .high = multicast >> 32,
        };
        struct plfxlc_mac *mac = plfxlc_hw_mac(hw);
        unsigned long flags;

        /* Only deal with supported flags */
        *new_flags &= SUPPORTED_FIF_FLAGS;

        /* If multicast parameter
         * (as returned by plfxlc_op_prepare_multicast)
         * has changed, no bit in changed_flags is set. To handle this
         * situation, we do not return if changed_flags is 0. If we do so,
         * we will have some issue with IPv6 which uses multicast for link
         * layer address resolution.
         */
        if (*new_flags & (FIF_ALLMULTI))
                plfxlc_mc_add_all(&hash);

        spin_lock_irqsave(&mac->lock, flags);
        mac->pass_failed_fcs = !!(*new_flags & FIF_FCSFAIL);
        mac->pass_ctrl = !!(*new_flags & FIF_CONTROL);
        mac->multicast_hash = hash;
        spin_unlock_irqrestore(&mac->lock, flags);

        /* no handling required for FIF_OTHER_BSS as we don't currently
         * do BSSID filtering
         */
        /* FIXME: in future it would be nice to enable the probe response
         * filter (so that the driver doesn't see them) until
         * FIF_BCN_PRBRESP_PROMISC is set. however due to atomicity here, we'd
         * have to schedule work to enable prbresp reception, which might
         * happen too late. For now we'll just listen and forward them all the
         * time.
         */
}

static void plfxlc_op_bss_info_changed(struct ieee80211_hw *hw,
                                       struct ieee80211_vif *vif,
                                       struct ieee80211_bss_conf *bss_conf,
                                       u64 changes)
{
        struct plfxlc_mac *mac = plfxlc_hw_mac(hw);
        int associated;

        dev_dbg(plfxlc_mac_dev(mac), "changes: %llx\n", changes);

        if (mac->type != NL80211_IFTYPE_ADHOC) { /* for STATION */
                associated = is_valid_ether_addr(bss_conf->bssid);
                goto exit_all;
        }
        /* for ADHOC */
        associated = true;
        if (changes & BSS_CHANGED_BEACON) {
                struct sk_buff *beacon = ieee80211_beacon_get(hw, vif, 0);

                if (beacon) {
                        /*beacon is hardcoded in firmware */
                        kfree_skb(beacon);
                        /*Returned skb is used only once and
                         * low-level driver is
                         * responsible for freeing it.
                         */
                }
        }

        if (changes & BSS_CHANGED_BEACON_ENABLED) {
                u16 interval = 0;
                u8 period = 0;

                if (bss_conf->enable_beacon) {
                        period = bss_conf->dtim_period;
                        interval = bss_conf->beacon_int;
                }

                spin_lock_irq(&mac->lock);
                mac->beacon.period = period;
                mac->beacon.interval = interval;
                mac->beacon.last_update = jiffies;
                spin_unlock_irq(&mac->lock);

                plfxlc_set_beacon_interval(&mac->chip, interval,
                                           period, mac->type);
        }
exit_all:
        spin_lock_irq(&mac->lock);
        mac->associated = associated;
        spin_unlock_irq(&mac->lock);
}

static int plfxlc_get_stats(struct ieee80211_hw *hw,
                            struct ieee80211_low_level_stats *stats)
{
        stats->dot11ACKFailureCount = 0;
        stats->dot11RTSFailureCount = 0;
        stats->dot11FCSErrorCount   = 0;
        stats->dot11RTSSuccessCount = 0;
        return 0;
}

static const char et_strings[][ETH_GSTRING_LEN] = {
        "phy_rssi",
        "phy_rx_crc_err"
};

static int plfxlc_get_et_sset_count(struct ieee80211_hw *hw,
                                    struct ieee80211_vif *vif, int sset)
{
        if (sset == ETH_SS_STATS)
                return ARRAY_SIZE(et_strings);

        return 0;
}

static void plfxlc_get_et_strings(struct ieee80211_hw *hw,
                                  struct ieee80211_vif *vif,
                                  u32 sset, u8 *data)
{
        if (sset == ETH_SS_STATS)
                memcpy(data, et_strings, sizeof(et_strings));
}

static void plfxlc_get_et_stats(struct ieee80211_hw *hw,
                                struct ieee80211_vif *vif,
                                struct ethtool_stats *stats, u64 *data)
{
        struct plfxlc_mac *mac = plfxlc_hw_mac(hw);

        data[0] = mac->rssi;
        data[1] = mac->crc_errors;
}

static int plfxlc_set_rts_threshold(struct ieee80211_hw *hw, int radio_idx,
                                    u32 value)
{
        return 0;
}

static const struct ieee80211_ops plfxlc_ops = {
        .add_chanctx = ieee80211_emulate_add_chanctx,
        .remove_chanctx = ieee80211_emulate_remove_chanctx,
        .change_chanctx = ieee80211_emulate_change_chanctx,
        .switch_vif_chanctx = ieee80211_emulate_switch_vif_chanctx,
        .tx = plfxlc_op_tx,
        .wake_tx_queue = ieee80211_handle_wake_tx_queue,
        .start = plfxlc_op_start,
        .stop = plfxlc_op_stop,
        .add_interface = plfxlc_op_add_interface,
        .remove_interface = plfxlc_op_remove_interface,
        .set_rts_threshold = plfxlc_set_rts_threshold,
        .config = plfxlc_op_config,
        .configure_filter = plfxlc_op_configure_filter,
        .bss_info_changed = plfxlc_op_bss_info_changed,
        .get_stats = plfxlc_get_stats,
        .get_et_sset_count = plfxlc_get_et_sset_count,
        .get_et_stats = plfxlc_get_et_stats,
        .get_et_strings = plfxlc_get_et_strings,
};

struct ieee80211_hw *plfxlc_mac_alloc_hw(struct usb_interface *intf)
{
        struct ieee80211_hw *hw;
        struct plfxlc_mac *mac;

        hw = ieee80211_alloc_hw(sizeof(struct plfxlc_mac), &plfxlc_ops);
        if (!hw) {
                dev_dbg(&intf->dev, "out of memory\n");
                return NULL;
        }
        set_wiphy_dev(hw->wiphy, &intf->dev);

        mac = plfxlc_hw_mac(hw);
        memset(mac, 0, sizeof(*mac));
        spin_lock_init(&mac->lock);
        mac->hw = hw;

        mac->type = NL80211_IFTYPE_UNSPECIFIED;

        memcpy(mac->channels, plfxlc_channels, sizeof(plfxlc_channels));
        memcpy(mac->rates, plfxlc_rates, sizeof(plfxlc_rates));
        mac->band.n_bitrates = ARRAY_SIZE(plfxlc_rates);
        mac->band.bitrates = mac->rates;
        mac->band.n_channels = ARRAY_SIZE(plfxlc_channels);
        mac->band.channels = mac->channels;
        hw->wiphy->bands[NL80211_BAND_LC] = &mac->band;
        hw->conf.chandef.width = NL80211_CHAN_WIDTH_20;

        ieee80211_hw_set(hw, RX_INCLUDES_FCS);
        ieee80211_hw_set(hw, SIGNAL_DBM);
        ieee80211_hw_set(hw, HOST_BROADCAST_PS_BUFFERING);
        ieee80211_hw_set(hw, MFP_CAPABLE);

        hw->wiphy->interface_modes =
                BIT(NL80211_IFTYPE_STATION) |
                BIT(NL80211_IFTYPE_ADHOC);
        hw->max_signal = 100;
        hw->queues = 1;
        /* 4 for 32 bit alignment if no tailroom */
        hw->extra_tx_headroom = sizeof(struct plfxlc_ctrlset) + 4;
        /* Tell mac80211 that we support multi rate retries */
        hw->max_rates = IEEE80211_TX_MAX_RATES;
        hw->max_rate_tries = 18;   /* 9 rates * 2 retries/rate */

        skb_queue_head_init(&mac->ack_wait_queue);
        mac->ack_pending = 0;

        plfxlc_chip_init(&mac->chip, hw, intf);

        SET_IEEE80211_DEV(hw, &intf->dev);
        return hw;
}

void plfxlc_mac_release_hw(struct ieee80211_hw *hw)
{
        plfxlc_chip_release(&plfxlc_hw_mac(hw)->chip);
        ieee80211_free_hw(hw);
}