Add the rt linux 4.1.3-rt3 as base
[kvmfornfv.git] / kernel / drivers / net / wireless / zd1211rw / zd_mac.c
diff --git a/kernel/drivers/net/wireless/zd1211rw/zd_mac.c b/kernel/drivers/net/wireless/zd1211rw/zd_mac.c
new file mode 100644 (file)
index 0000000..e7af261
--- /dev/null
@@ -0,0 +1,1550 @@
+/* ZD1211 USB-WLAN driver for Linux
+ *
+ * Copyright (C) 2005-2007 Ulrich Kunitz <kune@deine-taler.de>
+ * Copyright (C) 2006-2007 Daniel Drake <dsd@gentoo.org>
+ * Copyright (C) 2006-2007 Michael Wu <flamingice@sourmilk.net>
+ * Copyright (C) 2007-2008 Luis R. Rodriguez <mcgrof@winlab.rutgers.edu>
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License as published by
+ * the Free Software Foundation; either version 2 of the License, or
+ * (at your option) any later version.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ * GNU General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with this program; if not, see <http://www.gnu.org/licenses/>.
+ */
+
+#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 "zd_def.h"
+#include "zd_chip.h"
+#include "zd_mac.h"
+#include "zd_rf.h"
+
+struct zd_reg_alpha2_map {
+       u32 reg;
+       char alpha2[2];
+};
+
+static struct zd_reg_alpha2_map reg_alpha2_map[] = {
+       { ZD_REGDOMAIN_FCC, "US" },
+       { ZD_REGDOMAIN_IC, "CA" },
+       { ZD_REGDOMAIN_ETSI, "DE" }, /* Generic ETSI, use most restrictive */
+       { ZD_REGDOMAIN_JAPAN, "JP" },
+       { ZD_REGDOMAIN_JAPAN_2, "JP" },
+       { ZD_REGDOMAIN_JAPAN_3, "JP" },
+       { ZD_REGDOMAIN_SPAIN, "ES" },
+       { ZD_REGDOMAIN_FRANCE, "FR" },
+};
+
+/* This table contains the hardware specific values for the modulation rates. */
+static const struct ieee80211_rate zd_rates[] = {
+       { .bitrate = 10,
+         .hw_value = ZD_CCK_RATE_1M, },
+       { .bitrate = 20,
+         .hw_value = ZD_CCK_RATE_2M,
+         .hw_value_short = ZD_CCK_RATE_2M | ZD_CCK_PREA_SHORT,
+         .flags = IEEE80211_RATE_SHORT_PREAMBLE },
+       { .bitrate = 55,
+         .hw_value = ZD_CCK_RATE_5_5M,
+         .hw_value_short = ZD_CCK_RATE_5_5M | ZD_CCK_PREA_SHORT,
+         .flags = IEEE80211_RATE_SHORT_PREAMBLE },
+       { .bitrate = 110,
+         .hw_value = ZD_CCK_RATE_11M,
+         .hw_value_short = ZD_CCK_RATE_11M | ZD_CCK_PREA_SHORT,
+         .flags = IEEE80211_RATE_SHORT_PREAMBLE },
+       { .bitrate = 60,
+         .hw_value = ZD_OFDM_RATE_6M,
+         .flags = 0 },
+       { .bitrate = 90,
+         .hw_value = ZD_OFDM_RATE_9M,
+         .flags = 0 },
+       { .bitrate = 120,
+         .hw_value = ZD_OFDM_RATE_12M,
+         .flags = 0 },
+       { .bitrate = 180,
+         .hw_value = ZD_OFDM_RATE_18M,
+         .flags = 0 },
+       { .bitrate = 240,
+         .hw_value = ZD_OFDM_RATE_24M,
+         .flags = 0 },
+       { .bitrate = 360,
+         .hw_value = ZD_OFDM_RATE_36M,
+         .flags = 0 },
+       { .bitrate = 480,
+         .hw_value = ZD_OFDM_RATE_48M,
+         .flags = 0 },
+       { .bitrate = 540,
+         .hw_value = ZD_OFDM_RATE_54M,
+         .flags = 0 },
+};
+
+/*
+ * Zydas retry rates table. Each line is listed in the same order as
+ * in zd_rates[] and contains all the rate used when a packet is sent
+ * starting with a given rates. Let's consider an example :
+ *
+ * "11 Mbits : 4, 3, 2, 1, 0" means :
+ * - packet is sent using 4 different rates
+ * - 1st rate is index 3 (ie 11 Mbits)
+ * - 2nd rate is index 2 (ie 5.5 Mbits)
+ * - 3rd rate is index 1 (ie 2 Mbits)
+ * - 4th rate is index 0 (ie 1 Mbits)
+ */
+
+static const struct tx_retry_rate zd_retry_rates[] = {
+       { /*  1 Mbits */        1, { 0 }},
+       { /*  2 Mbits */        2, { 1,  0 }},
+       { /*  5.5 Mbits */      3, { 2,  1, 0 }},
+       { /* 11 Mbits */        4, { 3,  2, 1, 0 }},
+       { /*  6 Mbits */        5, { 4,  3, 2, 1, 0 }},
+       { /*  9 Mbits */        6, { 5,  4, 3, 2, 1, 0}},
+       { /* 12 Mbits */        5, { 6,  3, 2, 1, 0 }},
+       { /* 18 Mbits */        6, { 7,  6, 3, 2, 1, 0 }},
+       { /* 24 Mbits */        6, { 8,  6, 3, 2, 1, 0 }},
+       { /* 36 Mbits */        7, { 9,  8, 6, 3, 2, 1, 0 }},
+       { /* 48 Mbits */        8, {10,  9, 8, 6, 3, 2, 1, 0 }},
+       { /* 54 Mbits */        9, {11, 10, 9, 8, 6, 3, 2, 1, 0 }}
+};
+
+static const struct ieee80211_channel zd_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 },
+};
+
+static void housekeeping_init(struct zd_mac *mac);
+static void housekeeping_enable(struct zd_mac *mac);
+static void housekeeping_disable(struct zd_mac *mac);
+static void beacon_init(struct zd_mac *mac);
+static void beacon_enable(struct zd_mac *mac);
+static void beacon_disable(struct zd_mac *mac);
+static void set_rts_cts(struct zd_mac *mac, unsigned int short_preamble);
+static int zd_mac_config_beacon(struct ieee80211_hw *hw,
+                               struct sk_buff *beacon, bool in_intr);
+
+static int zd_reg2alpha2(u8 regdomain, char *alpha2)
+{
+       unsigned int i;
+       struct zd_reg_alpha2_map *reg_map;
+       for (i = 0; i < ARRAY_SIZE(reg_alpha2_map); i++) {
+               reg_map = &reg_alpha2_map[i];
+               if (regdomain == reg_map->reg) {
+                       alpha2[0] = reg_map->alpha2[0];
+                       alpha2[1] = reg_map->alpha2[1];
+                       return 0;
+               }
+       }
+       return 1;
+}
+
+static int zd_check_signal(struct ieee80211_hw *hw, int signal)
+{
+       struct zd_mac *mac = zd_hw_mac(hw);
+
+       dev_dbg_f_cond(zd_mac_dev(mac), signal < 0 || signal > 100,
+                       "%s: signal value from device not in range 0..100, "
+                       "but %d.\n", __func__, signal);
+
+       if (signal < 0)
+               signal = 0;
+       else if (signal > 100)
+               signal = 100;
+
+       return signal;
+}
+
+int zd_mac_preinit_hw(struct ieee80211_hw *hw)
+{
+       int r;
+       u8 addr[ETH_ALEN];
+       struct zd_mac *mac = zd_hw_mac(hw);
+
+       r = zd_chip_read_mac_addr_fw(&mac->chip, addr);
+       if (r)
+               return r;
+
+       SET_IEEE80211_PERM_ADDR(hw, addr);
+
+       return 0;
+}
+
+int zd_mac_init_hw(struct ieee80211_hw *hw)
+{
+       int r;
+       struct zd_mac *mac = zd_hw_mac(hw);
+       struct zd_chip *chip = &mac->chip;
+       char alpha2[2];
+       u8 default_regdomain;
+
+       r = zd_chip_enable_int(chip);
+       if (r)
+               goto out;
+       r = zd_chip_init_hw(chip);
+       if (r)
+               goto disable_int;
+
+       ZD_ASSERT(!irqs_disabled());
+
+       r = zd_read_regdomain(chip, &default_regdomain);
+       if (r)
+               goto disable_int;
+       spin_lock_irq(&mac->lock);
+       mac->regdomain = mac->default_regdomain = default_regdomain;
+       spin_unlock_irq(&mac->lock);
+
+       /* We must inform the device that we are doing encryption/decryption in
+        * software at the moment. */
+       r = zd_set_encryption_type(chip, ENC_SNIFFER);
+       if (r)
+               goto disable_int;
+
+       r = zd_reg2alpha2(mac->regdomain, alpha2);
+       if (r)
+               goto disable_int;
+
+       r = regulatory_hint(hw->wiphy, alpha2);
+disable_int:
+       zd_chip_disable_int(chip);
+out:
+       return r;
+}
+
+void zd_mac_clear(struct zd_mac *mac)
+{
+       flush_workqueue(zd_workqueue);
+       zd_chip_clear(&mac->chip);
+       ZD_ASSERT(!spin_is_locked(&mac->lock));
+       ZD_MEMCLEAR(mac, sizeof(struct zd_mac));
+}
+
+static int set_rx_filter(struct zd_mac *mac)
+{
+       unsigned long flags;
+       u32 filter = STA_RX_FILTER;
+
+       spin_lock_irqsave(&mac->lock, flags);
+       if (mac->pass_ctrl)
+               filter |= RX_FILTER_CTRL;
+       spin_unlock_irqrestore(&mac->lock, flags);
+
+       return zd_iowrite32(&mac->chip, CR_RX_FILTER, filter);
+}
+
+static int set_mac_and_bssid(struct zd_mac *mac)
+{
+       int r;
+
+       if (!mac->vif)
+               return -1;
+
+       r = zd_write_mac_addr(&mac->chip, mac->vif->addr);
+       if (r)
+               return r;
+
+       /* Vendor driver after setting MAC either sets BSSID for AP or
+        * filter for other modes.
+        */
+       if (mac->type != NL80211_IFTYPE_AP)
+               return set_rx_filter(mac);
+       else
+               return zd_write_bssid(&mac->chip, mac->vif->addr);
+}
+
+static int set_mc_hash(struct zd_mac *mac)
+{
+       struct zd_mc_hash hash;
+       zd_mc_clear(&hash);
+       return zd_chip_set_multicast_hash(&mac->chip, &hash);
+}
+
+int zd_op_start(struct ieee80211_hw *hw)
+{
+       struct zd_mac *mac = zd_hw_mac(hw);
+       struct zd_chip *chip = &mac->chip;
+       struct zd_usb *usb = &chip->usb;
+       int r;
+
+       if (!usb->initialized) {
+               r = zd_usb_init_hw(usb);
+               if (r)
+                       goto out;
+       }
+
+       r = zd_chip_enable_int(chip);
+       if (r < 0)
+               goto out;
+
+       r = zd_chip_set_basic_rates(chip, CR_RATES_80211B | CR_RATES_80211G);
+       if (r < 0)
+               goto disable_int;
+       r = set_rx_filter(mac);
+       if (r)
+               goto disable_int;
+       r = set_mc_hash(mac);
+       if (r)
+               goto disable_int;
+
+       /* Wait after setting the multicast hash table and powering on
+        * the radio otherwise interface bring up will fail. This matches
+        * what the vendor driver did.
+        */
+       msleep(10);
+
+       r = zd_chip_switch_radio_on(chip);
+       if (r < 0) {
+               dev_err(zd_chip_dev(chip),
+                       "%s: failed to set radio on\n", __func__);
+               goto disable_int;
+       }
+       r = zd_chip_enable_rxtx(chip);
+       if (r < 0)
+               goto disable_radio;
+       r = zd_chip_enable_hwint(chip);
+       if (r < 0)
+               goto disable_rxtx;
+
+       housekeeping_enable(mac);
+       beacon_enable(mac);
+       set_bit(ZD_DEVICE_RUNNING, &mac->flags);
+       return 0;
+disable_rxtx:
+       zd_chip_disable_rxtx(chip);
+disable_radio:
+       zd_chip_switch_radio_off(chip);
+disable_int:
+       zd_chip_disable_int(chip);
+out:
+       return r;
+}
+
+void zd_op_stop(struct ieee80211_hw *hw)
+{
+       struct zd_mac *mac = zd_hw_mac(hw);
+       struct zd_chip *chip = &mac->chip;
+       struct sk_buff *skb;
+       struct sk_buff_head *ack_wait_queue = &mac->ack_wait_queue;
+
+       clear_bit(ZD_DEVICE_RUNNING, &mac->flags);
+
+       /* The order here deliberately is a little different from the open()
+        * method, since we need to make sure there is no opportunity for RX
+        * frames to be processed by mac80211 after we have stopped it.
+        */
+
+       zd_chip_disable_rxtx(chip);
+       beacon_disable(mac);
+       housekeeping_disable(mac);
+       flush_workqueue(zd_workqueue);
+
+       zd_chip_disable_hwint(chip);
+       zd_chip_switch_radio_off(chip);
+       zd_chip_disable_int(chip);
+
+
+       while ((skb = skb_dequeue(ack_wait_queue)))
+               dev_kfree_skb_any(skb);
+}
+
+int zd_restore_settings(struct zd_mac *mac)
+{
+       struct sk_buff *beacon;
+       struct zd_mc_hash multicast_hash;
+       unsigned int short_preamble;
+       int r, beacon_interval, beacon_period;
+       u8 channel;
+
+       dev_dbg_f(zd_mac_dev(mac), "\n");
+
+       spin_lock_irq(&mac->lock);
+       multicast_hash = mac->multicast_hash;
+       short_preamble = mac->short_preamble;
+       beacon_interval = mac->beacon.interval;
+       beacon_period = mac->beacon.period;
+       channel = mac->channel;
+       spin_unlock_irq(&mac->lock);
+
+       r = set_mac_and_bssid(mac);
+       if (r < 0) {
+               dev_dbg_f(zd_mac_dev(mac), "set_mac_and_bssid failed, %d\n", r);
+               return r;
+       }
+
+       r = zd_chip_set_channel(&mac->chip, channel);
+       if (r < 0) {
+               dev_dbg_f(zd_mac_dev(mac), "zd_chip_set_channel failed, %d\n",
+                         r);
+               return r;
+       }
+
+       set_rts_cts(mac, short_preamble);
+
+       r = zd_chip_set_multicast_hash(&mac->chip, &multicast_hash);
+       if (r < 0) {
+               dev_dbg_f(zd_mac_dev(mac),
+                         "zd_chip_set_multicast_hash failed, %d\n", r);
+               return r;
+       }
+
+       if (mac->type == NL80211_IFTYPE_MESH_POINT ||
+           mac->type == NL80211_IFTYPE_ADHOC ||
+           mac->type == NL80211_IFTYPE_AP) {
+               if (mac->vif != NULL) {
+                       beacon = ieee80211_beacon_get(mac->hw, mac->vif);
+                       if (beacon)
+                               zd_mac_config_beacon(mac->hw, beacon, false);
+               }
+
+               zd_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;
+}
+
+/**
+ * zd_mac_tx_status - reports tx status of a packet if required
+ * @hw - a &struct ieee80211_hw pointer
+ * @skb - a sk-buffer
+ * @flags: extra flags to set in the TX status info
+ * @ackssi: ACK signal strength
+ * @success - True for successful transmission of the frame
+ *
+ * This information calls ieee80211_tx_status_irqsafe() if required by the
+ * control information. It copies the control information into the status
+ * information.
+ *
+ * If no status information has been requested, the skb is freed.
+ */
+static void zd_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 i;
+       int success = 1, retry = 1;
+       int first_idx;
+       const struct tx_retry_rate *retries;
+
+       ieee80211_tx_info_clear_status(info);
+
+       if (tx_status) {
+               success = !tx_status->failure;
+               retry = tx_status->retry + success;
+       }
+
+       if (success) {
+               /* success */
+               info->flags |= IEEE80211_TX_STAT_ACK;
+       } else {
+               /* failure */
+               info->flags &= ~IEEE80211_TX_STAT_ACK;
+       }
+
+       first_idx = info->status.rates[0].idx;
+       ZD_ASSERT(0<=first_idx && first_idx<ARRAY_SIZE(zd_retry_rates));
+       retries = &zd_retry_rates[first_idx];
+       ZD_ASSERT(1 <= retry && retry <= retries->count);
+
+       info->status.rates[0].idx = retries->rate[0];
+       info->status.rates[0].count = 1; // (retry > 1 ? 2 : 1);
+
+       for (i=1; i<IEEE80211_TX_MAX_RATES-1 && i<retry; i++) {
+               info->status.rates[i].idx = retries->rate[i];
+               info->status.rates[i].count = 1; // ((i==retry-1) && success ? 1:2);
+       }
+       for (; i<IEEE80211_TX_MAX_RATES && i<retry; i++) {
+               info->status.rates[i].idx = retries->rate[retry - 1];
+               info->status.rates[i].count = 1; // (success ? 1:2);
+       }
+       if (i<IEEE80211_TX_MAX_RATES)
+               info->status.rates[i].idx = -1; /* terminate */
+
+       info->status.ack_signal = zd_check_signal(hw, ackssi);
+       ieee80211_tx_status_irqsafe(hw, skb);
+}
+
+/**
+ * zd_mac_tx_failed - callback for failed frames
+ * @dev: the mac80211 wireless device
+ *
+ * This function is called if a frame couldn't be successfully
+ * transferred. The first frame from the tx queue, will be selected and
+ * reported as error to the upper layers.
+ */
+void zd_mac_tx_failed(struct urb *urb)
+{
+       struct ieee80211_hw * hw = zd_usb_to_hw(urb->context);
+       struct zd_mac *mac = zd_hw_mac(hw);
+       struct sk_buff_head *q = &mac->ack_wait_queue;
+       struct sk_buff *skb;
+       struct tx_status *tx_status = (struct tx_status *)urb->transfer_buffer;
+       unsigned long flags;
+       int success = !tx_status->failure;
+       int retry = tx_status->retry + success;
+       int found = 0;
+       int i, position = 0;
+
+       q = &mac->ack_wait_queue;
+       spin_lock_irqsave(&q->lock, flags);
+
+       skb_queue_walk(q, skb) {
+               struct ieee80211_hdr *tx_hdr;
+               struct ieee80211_tx_info *info;
+               int first_idx, final_idx;
+               const struct tx_retry_rate *retries;
+               u8 final_rate;
+
+               position ++;
+
+               /* if the hardware reports a failure and we had a 802.11 ACK
+                * pending, then we skip the first skb when searching for a
+                * matching frame */
+               if (tx_status->failure && mac->ack_pending &&
+                   skb_queue_is_first(q, skb)) {
+                       continue;
+               }
+
+               tx_hdr = (struct ieee80211_hdr *)skb->data;
+
+               /* we skip all frames not matching the reported destination */
+               if (unlikely(!ether_addr_equal(tx_hdr->addr1, tx_status->mac)))
+                       continue;
+
+               /* we skip all frames not matching the reported final rate */
+
+               info = IEEE80211_SKB_CB(skb);
+               first_idx = info->status.rates[0].idx;
+               ZD_ASSERT(0<=first_idx && first_idx<ARRAY_SIZE(zd_retry_rates));
+               retries = &zd_retry_rates[first_idx];
+               if (retry <= 0 || retry > retries->count)
+                       continue;
+
+               final_idx = retries->rate[retry - 1];
+               final_rate = zd_rates[final_idx].hw_value;
+
+               if (final_rate != tx_status->rate) {
+                       continue;
+               }
+
+               found = 1;
+               break;
+       }
+
+       if (found) {
+               for (i=1; i<=position; i++) {
+                       skb = __skb_dequeue(q);
+                       zd_mac_tx_status(hw, skb,
+                                        mac->ack_pending ? mac->ack_signal : 0,
+                                        i == position ? tx_status : NULL);
+                       mac->ack_pending = 0;
+               }
+       }
+
+       spin_unlock_irqrestore(&q->lock, flags);
+}
+
+/**
+ * zd_mac_tx_to_dev - callback for USB layer
+ * @skb: a &sk_buff pointer
+ * @error: error value, 0 if transmission successful
+ *
+ * Informs the MAC layer that the frame has successfully transferred to the
+ * device. If an ACK is required and the transfer to the device has been
+ * successful, the packets are put on the @ack_wait_queue with
+ * the control set removed.
+ */
+void zd_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 zd_mac *mac = zd_hw_mac(hw);
+
+       ieee80211_tx_info_clear_status(info);
+
+       skb_pull(skb, sizeof(struct zd_ctrlset));
+       if (unlikely(error ||
+           (info->flags & IEEE80211_TX_CTL_NO_ACK))) {
+               /*
+                * FIXME : do we need to fill in anything ?
+                */
+               ieee80211_tx_status_irqsafe(hw, skb);
+       } else {
+               struct sk_buff_head *q = &mac->ack_wait_queue;
+
+               skb_queue_tail(q, skb);
+               while (skb_queue_len(q) > ZD_MAC_MAX_ACK_WAITERS) {
+                       zd_mac_tx_status(hw, skb_dequeue(q),
+                                        mac->ack_pending ? mac->ack_signal : 0,
+                                        NULL);
+                       mac->ack_pending = 0;
+               }
+       }
+}
+
+static int zd_calc_tx_length_us(u8 *service, u8 zd_rate, u16 tx_length)
+{
+       /* ZD_PURE_RATE() must be used to remove the modulation type flag of
+        * the zd-rate values.
+        */
+       static const u8 rate_divisor[] = {
+               [ZD_PURE_RATE(ZD_CCK_RATE_1M)]   =  1,
+               [ZD_PURE_RATE(ZD_CCK_RATE_2M)]   =  2,
+               /* Bits must be doubled. */
+               [ZD_PURE_RATE(ZD_CCK_RATE_5_5M)] = 11,
+               [ZD_PURE_RATE(ZD_CCK_RATE_11M)]  = 11,
+               [ZD_PURE_RATE(ZD_OFDM_RATE_6M)]  =  6,
+               [ZD_PURE_RATE(ZD_OFDM_RATE_9M)]  =  9,
+               [ZD_PURE_RATE(ZD_OFDM_RATE_12M)] = 12,
+               [ZD_PURE_RATE(ZD_OFDM_RATE_18M)] = 18,
+               [ZD_PURE_RATE(ZD_OFDM_RATE_24M)] = 24,
+               [ZD_PURE_RATE(ZD_OFDM_RATE_36M)] = 36,
+               [ZD_PURE_RATE(ZD_OFDM_RATE_48M)] = 48,
+               [ZD_PURE_RATE(ZD_OFDM_RATE_54M)] = 54,
+       };
+
+       u32 bits = (u32)tx_length * 8;
+       u32 divisor;
+
+       divisor = rate_divisor[ZD_PURE_RATE(zd_rate)];
+       if (divisor == 0)
+               return -EINVAL;
+
+       switch (zd_rate) {
+       case ZD_CCK_RATE_5_5M:
+               bits = (2*bits) + 10; /* round up to the next integer */
+               break;
+       case ZD_CCK_RATE_11M:
+               if (service) {
+                       u32 t = bits % 11;
+                       *service &= ~ZD_PLCP_SERVICE_LENGTH_EXTENSION;
+                       if (0 < t && t <= 3) {
+                               *service |= ZD_PLCP_SERVICE_LENGTH_EXTENSION;
+                       }
+               }
+               bits += 10; /* round up to the next integer */
+               break;
+       }
+
+       return bits/divisor;
+}
+
+static void cs_set_control(struct zd_mac *mac, struct zd_ctrlset *cs,
+                          struct ieee80211_hdr *header,
+                          struct ieee80211_tx_info *info)
+{
+       /*
+        * CONTROL TODO:
+        * - if backoff needed, enable bit 0
+        * - if burst (backoff not needed) disable bit 0
+        */
+
+       cs->control = 0;
+
+       /* First fragment */
+       if (info->flags & IEEE80211_TX_CTL_FIRST_FRAGMENT)
+               cs->control |= ZD_CS_NEED_RANDOM_BACKOFF;
+
+       /* No ACK expected (multicast, etc.) */
+       if (info->flags & IEEE80211_TX_CTL_NO_ACK)
+               cs->control |= ZD_CS_NO_ACK;
+
+       /* PS-POLL */
+       if (ieee80211_is_pspoll(header->frame_control))
+               cs->control |= ZD_CS_PS_POLL_FRAME;
+
+       if (info->control.rates[0].flags & IEEE80211_TX_RC_USE_RTS_CTS)
+               cs->control |= ZD_CS_RTS;
+
+       if (info->control.rates[0].flags & IEEE80211_TX_RC_USE_CTS_PROTECT)
+               cs->control |= ZD_CS_SELF_CTS;
+
+       /* FIXME: Management frame? */
+}
+
+static bool zd_mac_match_cur_beacon(struct zd_mac *mac, struct sk_buff *beacon)
+{
+       if (!mac->beacon.cur_beacon)
+               return false;
+
+       if (mac->beacon.cur_beacon->len != beacon->len)
+               return false;
+
+       return !memcmp(beacon->data, mac->beacon.cur_beacon->data, beacon->len);
+}
+
+static void zd_mac_free_cur_beacon_locked(struct zd_mac *mac)
+{
+       ZD_ASSERT(mutex_is_locked(&mac->chip.mutex));
+
+       kfree_skb(mac->beacon.cur_beacon);
+       mac->beacon.cur_beacon = NULL;
+}
+
+static void zd_mac_free_cur_beacon(struct zd_mac *mac)
+{
+       mutex_lock(&mac->chip.mutex);
+       zd_mac_free_cur_beacon_locked(mac);
+       mutex_unlock(&mac->chip.mutex);
+}
+
+static int zd_mac_config_beacon(struct ieee80211_hw *hw, struct sk_buff *beacon,
+                               bool in_intr)
+{
+       struct zd_mac *mac = zd_hw_mac(hw);
+       int r, ret, num_cmds, req_pos = 0;
+       u32 tmp, j = 0;
+       /* 4 more bytes for tail CRC */
+       u32 full_len = beacon->len + 4;
+       unsigned long end_jiffies, message_jiffies;
+       struct zd_ioreq32 *ioreqs;
+
+       mutex_lock(&mac->chip.mutex);
+
+       /* Check if hw already has this beacon. */
+       if (zd_mac_match_cur_beacon(mac, beacon)) {
+               r = 0;
+               goto out_nofree;
+       }
+
+       /* Alloc memory for full beacon write at once. */
+       num_cmds = 1 + zd_chip_is_zd1211b(&mac->chip) + full_len;
+       ioreqs = kmalloc(num_cmds * sizeof(struct zd_ioreq32), GFP_KERNEL);
+       if (!ioreqs) {
+               r = -ENOMEM;
+               goto out_nofree;
+       }
+
+       r = zd_iowrite32_locked(&mac->chip, 0, CR_BCN_FIFO_SEMAPHORE);
+       if (r < 0)
+               goto out;
+       r = zd_ioread32_locked(&mac->chip, &tmp, CR_BCN_FIFO_SEMAPHORE);
+       if (r < 0)
+               goto release_sema;
+       if (in_intr && tmp & 0x2) {
+               r = -EBUSY;
+               goto release_sema;
+       }
+
+       end_jiffies = jiffies + HZ / 2; /*~500ms*/
+       message_jiffies = jiffies + HZ / 10; /*~100ms*/
+       while (tmp & 0x2) {
+               r = zd_ioread32_locked(&mac->chip, &tmp, CR_BCN_FIFO_SEMAPHORE);
+               if (r < 0)
+                       goto release_sema;
+               if (time_is_before_eq_jiffies(message_jiffies)) {
+                       message_jiffies = jiffies + HZ / 10;
+                       dev_err(zd_mac_dev(mac),
+                                       "CR_BCN_FIFO_SEMAPHORE not ready\n");
+                       if (time_is_before_eq_jiffies(end_jiffies))  {
+                               dev_err(zd_mac_dev(mac),
+                                               "Giving up beacon config.\n");
+                               r = -ETIMEDOUT;
+                               goto reset_device;
+                       }
+               }
+               msleep(20);
+       }
+
+       ioreqs[req_pos].addr = CR_BCN_FIFO;
+       ioreqs[req_pos].value = full_len - 1;
+       req_pos++;
+       if (zd_chip_is_zd1211b(&mac->chip)) {
+               ioreqs[req_pos].addr = CR_BCN_LENGTH;
+               ioreqs[req_pos].value = full_len - 1;
+               req_pos++;
+       }
+
+       for (j = 0 ; j < beacon->len; j++) {
+               ioreqs[req_pos].addr = CR_BCN_FIFO;
+               ioreqs[req_pos].value = *((u8 *)(beacon->data + j));
+               req_pos++;
+       }
+
+       for (j = 0; j < 4; j++) {
+               ioreqs[req_pos].addr = CR_BCN_FIFO;
+               ioreqs[req_pos].value = 0x0;
+               req_pos++;
+       }
+
+       BUG_ON(req_pos != num_cmds);
+
+       r = zd_iowrite32a_locked(&mac->chip, ioreqs, num_cmds);
+
+release_sema:
+       /*
+        * Try very hard to release device beacon semaphore, as otherwise
+        * device/driver can be left in unusable state.
+        */
+       end_jiffies = jiffies + HZ / 2; /*~500ms*/
+       ret = zd_iowrite32_locked(&mac->chip, 1, CR_BCN_FIFO_SEMAPHORE);
+       while (ret < 0) {
+               if (in_intr || time_is_before_eq_jiffies(end_jiffies)) {
+                       ret = -ETIMEDOUT;
+                       break;
+               }
+
+               msleep(20);
+               ret = zd_iowrite32_locked(&mac->chip, 1, CR_BCN_FIFO_SEMAPHORE);
+       }
+
+       if (ret < 0)
+               dev_err(zd_mac_dev(mac), "Could not release "
+                                        "CR_BCN_FIFO_SEMAPHORE!\n");
+       if (r < 0 || ret < 0) {
+               if (r >= 0)
+                       r = ret;
+
+               /* We don't know if beacon was written successfully or not,
+                * so clear current. */
+               zd_mac_free_cur_beacon_locked(mac);
+
+               goto out;
+       }
+
+       /* Beacon has now been written successfully, update current. */
+       zd_mac_free_cur_beacon_locked(mac);
+       mac->beacon.cur_beacon = beacon;
+       beacon = NULL;
+
+       /* 802.11b/g 2.4G CCK 1Mb
+        * 802.11a, not yet implemented, uses different values (see GPL vendor
+        * driver)
+        */
+       r = zd_iowrite32_locked(&mac->chip, 0x00000400 | (full_len << 19),
+                               CR_BCN_PLCP_CFG);
+out:
+       kfree(ioreqs);
+out_nofree:
+       kfree_skb(beacon);
+       mutex_unlock(&mac->chip.mutex);
+
+       return r;
+
+reset_device:
+       zd_mac_free_cur_beacon_locked(mac);
+       kfree_skb(beacon);
+
+       mutex_unlock(&mac->chip.mutex);
+       kfree(ioreqs);
+
+       /* semaphore stuck, reset device to avoid fw freeze later */
+       dev_warn(zd_mac_dev(mac), "CR_BCN_FIFO_SEMAPHORE stuck, "
+                                 "resetting device...");
+       usb_queue_reset_device(mac->chip.usb.intf);
+
+       return r;
+}
+
+static int fill_ctrlset(struct zd_mac *mac,
+                       struct sk_buff *skb)
+{
+       int r;
+       struct ieee80211_hdr *hdr = (struct ieee80211_hdr *) skb->data;
+       unsigned int frag_len = skb->len + FCS_LEN;
+       unsigned int packet_length;
+       struct ieee80211_rate *txrate;
+       struct zd_ctrlset *cs = (struct zd_ctrlset *)
+               skb_push(skb, sizeof(struct zd_ctrlset));
+       struct ieee80211_tx_info *info = IEEE80211_SKB_CB(skb);
+
+       ZD_ASSERT(frag_len <= 0xffff);
+
+       /*
+        * Firmware computes the duration itself (for all frames except PSPoll)
+        * and needs the field set to 0 at input, otherwise firmware messes up
+        * duration_id and sets bits 14 and 15 on.
+        */
+       if (!ieee80211_is_pspoll(hdr->frame_control))
+               hdr->duration_id = 0;
+
+       txrate = ieee80211_get_tx_rate(mac->hw, info);
+
+       cs->modulation = txrate->hw_value;
+       if (info->control.rates[0].flags & IEEE80211_TX_RC_USE_SHORT_PREAMBLE)
+               cs->modulation = txrate->hw_value_short;
+
+       cs->tx_length = cpu_to_le16(frag_len);
+
+       cs_set_control(mac, cs, hdr, info);
+
+       packet_length = frag_len + sizeof(struct zd_ctrlset) + 10;
+       ZD_ASSERT(packet_length <= 0xffff);
+       /* ZD1211B: Computing the length difference this way, gives us
+        * flexibility to compute the packet length.
+        */
+       cs->packet_length = cpu_to_le16(zd_chip_is_zd1211b(&mac->chip) ?
+                       packet_length - frag_len : packet_length);
+
+       /*
+        * CURRENT LENGTH:
+        * - transmit frame length in microseconds
+        * - seems to be derived from frame length
+        * - see Cal_Us_Service() in zdinlinef.h
+        * - if macp->bTxBurstEnable is enabled, then multiply by 4
+        *  - bTxBurstEnable is never set in the vendor driver
+        *
+        * SERVICE:
+        * - "for PLCP configuration"
+        * - always 0 except in some situations at 802.11b 11M
+        * - see line 53 of zdinlinef.h
+        */
+       cs->service = 0;
+       r = zd_calc_tx_length_us(&cs->service, ZD_RATE(cs->modulation),
+                                le16_to_cpu(cs->tx_length));
+       if (r < 0)
+               return r;
+       cs->current_length = cpu_to_le16(r);
+       cs->next_frame_length = 0;
+
+       return 0;
+}
+
+/**
+ * zd_op_tx - transmits a network frame to the device
+ *
+ * @dev: mac80211 hardware device
+ * @skb: socket buffer
+ * @control: the control structure
+ *
+ * This function transmit an IEEE 802.11 network frame to the device. The
+ * control block of the skbuff will be initialized. If necessary the incoming
+ * mac80211 queues will be stopped.
+ */
+static void zd_op_tx(struct ieee80211_hw *hw,
+                    struct ieee80211_tx_control *control,
+                    struct sk_buff *skb)
+{
+       struct zd_mac *mac = zd_hw_mac(hw);
+       struct ieee80211_tx_info *info = IEEE80211_SKB_CB(skb);
+       int r;
+
+       r = fill_ctrlset(mac, skb);
+       if (r)
+               goto fail;
+
+       info->rate_driver_data[0] = hw;
+
+       r = zd_usb_tx(&mac->chip.usb, skb);
+       if (r)
+               goto fail;
+       return;
+
+fail:
+       dev_kfree_skb(skb);
+}
+
+/**
+ * filter_ack - filters incoming packets for acknowledgements
+ * @dev: the mac80211 device
+ * @rx_hdr: received header
+ * @stats: the status for the received packet
+ *
+ * This functions looks for ACK packets and tries to match them with the
+ * frames in the tx queue. If a match is found the frame will be dequeued and
+ * the upper layers is informed about the successful transmission. If
+ * mac80211 queues have been stopped and the number of frames still to be
+ * transmitted is low the queues will be opened again.
+ *
+ * Returns 1 if the frame was an ACK, 0 if it was ignored.
+ */
+static int filter_ack(struct ieee80211_hw *hw, struct ieee80211_hdr *rx_hdr,
+                     struct ieee80211_rx_status *stats)
+{
+       struct zd_mac *mac = zd_hw_mac(hw);
+       struct sk_buff *skb;
+       struct sk_buff_head *q;
+       unsigned long flags;
+       int found = 0;
+       int i, position = 0;
+
+       if (!ieee80211_is_ack(rx_hdr->frame_control))
+               return 0;
+
+       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;
+
+               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);
+                       zd_mac_tx_status(hw, skb,
+                                        mac->ack_pending ? mac->ack_signal : 0,
+                                        NULL);
+                       mac->ack_pending = 0;
+               }
+
+               mac->ack_pending = 1;
+               mac->ack_signal = stats->signal;
+
+               /* Prevent pending tx-packet on AP-mode */
+               if (mac->type == NL80211_IFTYPE_AP) {
+                       skb = __skb_dequeue(q);
+                       zd_mac_tx_status(hw, skb, mac->ack_signal, NULL);
+                       mac->ack_pending = 0;
+               }
+       }
+
+       spin_unlock_irqrestore(&q->lock, flags);
+       return 1;
+}
+
+int zd_mac_rx(struct ieee80211_hw *hw, const u8 *buffer, unsigned int length)
+{
+       struct zd_mac *mac = zd_hw_mac(hw);
+       struct ieee80211_rx_status stats;
+       const struct rx_status *status;
+       struct sk_buff *skb;
+       int bad_frame = 0;
+       __le16 fc;
+       int need_padding;
+       int i;
+       u8 rate;
+
+       if (length < ZD_PLCP_HEADER_SIZE + 10 /* IEEE80211_1ADDR_LEN */ +
+                    FCS_LEN + sizeof(struct rx_status))
+               return -EINVAL;
+
+       memset(&stats, 0, sizeof(stats));
+
+       /* Note about pass_failed_fcs and pass_ctrl access below:
+        * mac locking intentionally omitted here, as this is the only unlocked
+        * reader and the only writer is configure_filter. Plus, if there were
+        * any races accessing these variables, it wouldn't really matter.
+        * If mac80211 ever provides a way for us to access filter flags
+        * from outside configure_filter, we could improve on this. Also, this
+        * situation may change once we implement some kind of DMA-into-skb
+        * RX path. */
+
+       /* Caller has to ensure that length >= sizeof(struct rx_status). */
+       status = (struct rx_status *)
+               (buffer + (length - sizeof(struct rx_status)));
+       if (status->frame_status & ZD_RX_ERROR) {
+               if (mac->pass_failed_fcs &&
+                               (status->frame_status & ZD_RX_CRC32_ERROR)) {
+                       stats.flag |= RX_FLAG_FAILED_FCS_CRC;
+                       bad_frame = 1;
+               } else {
+                       return -EINVAL;
+               }
+       }
+
+       stats.freq = zd_channels[_zd_chip_get_channel(&mac->chip) - 1].center_freq;
+       stats.band = IEEE80211_BAND_2GHZ;
+       stats.signal = zd_check_signal(hw, status->signal_strength);
+
+       rate = zd_rx_rate(buffer, status);
+
+       /* todo: return index in the big switches in zd_rx_rate instead */
+       for (i = 0; i < mac->band.n_bitrates; i++)
+               if (rate == mac->band.bitrates[i].hw_value)
+                       stats.rate_idx = i;
+
+       length -= ZD_PLCP_HEADER_SIZE + sizeof(struct rx_status);
+       buffer += ZD_PLCP_HEADER_SIZE;
+
+       /* Except for bad frames, filter each frame to see if it is an ACK, in
+        * which case our internal TX tracking is updated. Normally we then
+        * bail here as there's no need to pass ACKs on up to the stack, but
+        * there is also the case where the stack has requested us to pass
+        * control frames on up (pass_ctrl) which we must consider. */
+       if (!bad_frame &&
+                       filter_ack(hw, (struct ieee80211_hdr *)buffer, &stats)
+                       && !mac->pass_ctrl)
+               return 0;
+
+       fc = get_unaligned((__le16*)buffer);
+       need_padding = ieee80211_is_data_qos(fc) ^ ieee80211_has_a4(fc);
+
+       skb = dev_alloc_skb(length + (need_padding ? 2 : 0));
+       if (skb == NULL)
+               return -ENOMEM;
+       if (need_padding) {
+               /* Make sure the payload data is 4 byte aligned. */
+               skb_reserve(skb, 2);
+       }
+
+       /* FIXME : could we avoid this big memcpy ? */
+       memcpy(skb_put(skb, length), buffer, length);
+
+       memcpy(IEEE80211_SKB_RXCB(skb), &stats, sizeof(stats));
+       ieee80211_rx_irqsafe(hw, skb);
+       return 0;
+}
+
+static int zd_op_add_interface(struct ieee80211_hw *hw,
+                               struct ieee80211_vif *vif)
+{
+       struct zd_mac *mac = zd_hw_mac(hw);
+
+       /* using NL80211_IFTYPE_UNSPECIFIED to indicate no mode selected */
+       if (mac->type != NL80211_IFTYPE_UNSPECIFIED)
+               return -EOPNOTSUPP;
+
+       switch (vif->type) {
+       case NL80211_IFTYPE_MONITOR:
+       case NL80211_IFTYPE_MESH_POINT:
+       case NL80211_IFTYPE_STATION:
+       case NL80211_IFTYPE_ADHOC:
+       case NL80211_IFTYPE_AP:
+               mac->type = vif->type;
+               break;
+       default:
+               return -EOPNOTSUPP;
+       }
+
+       mac->vif = vif;
+
+       return set_mac_and_bssid(mac);
+}
+
+static void zd_op_remove_interface(struct ieee80211_hw *hw,
+                                   struct ieee80211_vif *vif)
+{
+       struct zd_mac *mac = zd_hw_mac(hw);
+       mac->type = NL80211_IFTYPE_UNSPECIFIED;
+       mac->vif = NULL;
+       zd_set_beacon_interval(&mac->chip, 0, 0, NL80211_IFTYPE_UNSPECIFIED);
+       zd_write_mac_addr(&mac->chip, NULL);
+
+       zd_mac_free_cur_beacon(mac);
+}
+
+static int zd_op_config(struct ieee80211_hw *hw, u32 changed)
+{
+       struct zd_mac *mac = zd_hw_mac(hw);
+       struct ieee80211_conf *conf = &hw->conf;
+
+       spin_lock_irq(&mac->lock);
+       mac->channel = conf->chandef.chan->hw_value;
+       spin_unlock_irq(&mac->lock);
+
+       return zd_chip_set_channel(&mac->chip, conf->chandef.chan->hw_value);
+}
+
+static void zd_beacon_done(struct zd_mac *mac)
+{
+       struct sk_buff *skb, *beacon;
+
+       if (!test_bit(ZD_DEVICE_RUNNING, &mac->flags))
+               return;
+       if (!mac->vif || mac->vif->type != NL80211_IFTYPE_AP)
+               return;
+
+       /*
+        * Send out buffered broad- and multicast frames.
+        */
+       while (!ieee80211_queue_stopped(mac->hw, 0)) {
+               skb = ieee80211_get_buffered_bc(mac->hw, mac->vif);
+               if (!skb)
+                       break;
+               zd_op_tx(mac->hw, NULL, skb);
+       }
+
+       /*
+        * Fetch next beacon so that tim_count is updated.
+        */
+       beacon = ieee80211_beacon_get(mac->hw, mac->vif);
+       if (beacon)
+               zd_mac_config_beacon(mac->hw, beacon, true);
+
+       spin_lock_irq(&mac->lock);
+       mac->beacon.last_update = jiffies;
+       spin_unlock_irq(&mac->lock);
+}
+
+static void zd_process_intr(struct work_struct *work)
+{
+       u16 int_status;
+       unsigned long flags;
+       struct zd_mac *mac = container_of(work, struct zd_mac, process_intr);
+
+       spin_lock_irqsave(&mac->lock, flags);
+       int_status = le16_to_cpu(*(__le16 *)(mac->intr_buffer + 4));
+       spin_unlock_irqrestore(&mac->lock, flags);
+
+       if (int_status & INT_CFG_NEXT_BCN) {
+               /*dev_dbg_f_limit(zd_mac_dev(mac), "INT_CFG_NEXT_BCN\n");*/
+               zd_beacon_done(mac);
+       } else {
+               dev_dbg_f(zd_mac_dev(mac), "Unsupported interrupt\n");
+       }
+
+       zd_chip_enable_hwint(&mac->chip);
+}
+
+
+static u64 zd_op_prepare_multicast(struct ieee80211_hw *hw,
+                                  struct netdev_hw_addr_list *mc_list)
+{
+       struct zd_mac *mac = zd_hw_mac(hw);
+       struct zd_mc_hash hash;
+       struct netdev_hw_addr *ha;
+
+       zd_mc_clear(&hash);
+
+       netdev_hw_addr_list_for_each(ha, mc_list) {
+               dev_dbg_f(zd_mac_dev(mac), "mc addr %pM\n", ha->addr);
+               zd_mc_add_addr(&hash, ha->addr);
+       }
+
+       return hash.low | ((u64)hash.high << 32);
+}
+
+#define SUPPORTED_FIF_FLAGS \
+       (FIF_PROMISC_IN_BSS | FIF_ALLMULTI | FIF_FCSFAIL | FIF_CONTROL | \
+       FIF_OTHER_BSS | FIF_BCN_PRBRESP_PROMISC)
+static void zd_op_configure_filter(struct ieee80211_hw *hw,
+                       unsigned int changed_flags,
+                       unsigned int *new_flags,
+                       u64 multicast)
+{
+       struct zd_mc_hash hash = {
+               .low = multicast,
+               .high = multicast >> 32,
+       };
+       struct zd_mac *mac = zd_hw_mac(hw);
+       unsigned long flags;
+       int r;
+
+       /* Only deal with supported flags */
+       changed_flags &= SUPPORTED_FIF_FLAGS;
+       *new_flags &= SUPPORTED_FIF_FLAGS;
+
+       /*
+        * If multicast parameter (as returned by zd_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_PROMISC_IN_BSS | FIF_ALLMULTI))
+               zd_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);
+
+       zd_chip_set_multicast_hash(&mac->chip, &hash);
+
+       if (changed_flags & FIF_CONTROL) {
+               r = set_rx_filter(mac);
+               if (r)
+                       dev_err(zd_mac_dev(mac), "set_rx_filter error %d\n", r);
+       }
+
+       /* 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 set_rts_cts(struct zd_mac *mac, unsigned int short_preamble)
+{
+       mutex_lock(&mac->chip.mutex);
+       zd_chip_set_rts_cts_rate_locked(&mac->chip, short_preamble);
+       mutex_unlock(&mac->chip.mutex);
+}
+
+static void zd_op_bss_info_changed(struct ieee80211_hw *hw,
+                                  struct ieee80211_vif *vif,
+                                  struct ieee80211_bss_conf *bss_conf,
+                                  u32 changes)
+{
+       struct zd_mac *mac = zd_hw_mac(hw);
+       int associated;
+
+       dev_dbg_f(zd_mac_dev(mac), "changes: %x\n", changes);
+
+       if (mac->type == NL80211_IFTYPE_MESH_POINT ||
+           mac->type == NL80211_IFTYPE_ADHOC ||
+           mac->type == NL80211_IFTYPE_AP) {
+               associated = true;
+               if (changes & BSS_CHANGED_BEACON) {
+                       struct sk_buff *beacon = ieee80211_beacon_get(hw, vif);
+
+                       if (beacon) {
+                               zd_chip_disable_hwint(&mac->chip);
+                               zd_mac_config_beacon(hw, beacon, false);
+                               zd_chip_enable_hwint(&mac->chip);
+                       }
+               }
+
+               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);
+
+                       zd_set_beacon_interval(&mac->chip, interval, period,
+                                              mac->type);
+               }
+       } else
+               associated = is_valid_ether_addr(bss_conf->bssid);
+
+       spin_lock_irq(&mac->lock);
+       mac->associated = associated;
+       spin_unlock_irq(&mac->lock);
+
+       /* TODO: do hardware bssid filtering */
+
+       if (changes & BSS_CHANGED_ERP_PREAMBLE) {
+               spin_lock_irq(&mac->lock);
+               mac->short_preamble = bss_conf->use_short_preamble;
+               spin_unlock_irq(&mac->lock);
+
+               set_rts_cts(mac, bss_conf->use_short_preamble);
+       }
+}
+
+static u64 zd_op_get_tsf(struct ieee80211_hw *hw, struct ieee80211_vif *vif)
+{
+       struct zd_mac *mac = zd_hw_mac(hw);
+       return zd_chip_get_tsf(&mac->chip);
+}
+
+static const struct ieee80211_ops zd_ops = {
+       .tx                     = zd_op_tx,
+       .start                  = zd_op_start,
+       .stop                   = zd_op_stop,
+       .add_interface          = zd_op_add_interface,
+       .remove_interface       = zd_op_remove_interface,
+       .config                 = zd_op_config,
+       .prepare_multicast      = zd_op_prepare_multicast,
+       .configure_filter       = zd_op_configure_filter,
+       .bss_info_changed       = zd_op_bss_info_changed,
+       .get_tsf                = zd_op_get_tsf,
+};
+
+struct ieee80211_hw *zd_mac_alloc_hw(struct usb_interface *intf)
+{
+       struct zd_mac *mac;
+       struct ieee80211_hw *hw;
+
+       hw = ieee80211_alloc_hw(sizeof(struct zd_mac), &zd_ops);
+       if (!hw) {
+               dev_dbg_f(&intf->dev, "out of memory\n");
+               return NULL;
+       }
+
+       mac = zd_hw_mac(hw);
+
+       memset(mac, 0, sizeof(*mac));
+       spin_lock_init(&mac->lock);
+       mac->hw = hw;
+
+       mac->type = NL80211_IFTYPE_UNSPECIFIED;
+
+       memcpy(mac->channels, zd_channels, sizeof(zd_channels));
+       memcpy(mac->rates, zd_rates, sizeof(zd_rates));
+       mac->band.n_bitrates = ARRAY_SIZE(zd_rates);
+       mac->band.bitrates = mac->rates;
+       mac->band.n_channels = ARRAY_SIZE(zd_channels);
+       mac->band.channels = mac->channels;
+
+       hw->wiphy->bands[IEEE80211_BAND_2GHZ] = &mac->band;
+
+       hw->flags = IEEE80211_HW_RX_INCLUDES_FCS |
+                   IEEE80211_HW_SIGNAL_UNSPEC |
+                   IEEE80211_HW_HOST_BROADCAST_PS_BUFFERING |
+                   IEEE80211_HW_MFP_CAPABLE;
+
+       hw->wiphy->interface_modes =
+               BIT(NL80211_IFTYPE_MESH_POINT) |
+               BIT(NL80211_IFTYPE_STATION) |
+               BIT(NL80211_IFTYPE_ADHOC) |
+               BIT(NL80211_IFTYPE_AP);
+
+       hw->max_signal = 100;
+       hw->queues = 1;
+       hw->extra_tx_headroom = sizeof(struct zd_ctrlset);
+
+       /*
+        * 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;
+
+       zd_chip_init(&mac->chip, hw, intf);
+       housekeeping_init(mac);
+       beacon_init(mac);
+       INIT_WORK(&mac->process_intr, zd_process_intr);
+
+       SET_IEEE80211_DEV(hw, &intf->dev);
+       return hw;
+}
+
+#define BEACON_WATCHDOG_DELAY round_jiffies_relative(HZ)
+
+static void beacon_watchdog_handler(struct work_struct *work)
+{
+       struct zd_mac *mac =
+               container_of(work, struct zd_mac, beacon.watchdog_work.work);
+       struct sk_buff *beacon;
+       unsigned long timeout;
+       int interval, period;
+
+       if (!test_bit(ZD_DEVICE_RUNNING, &mac->flags))
+               goto rearm;
+       if (mac->type != NL80211_IFTYPE_AP || !mac->vif)
+               goto rearm;
+
+       spin_lock_irq(&mac->lock);
+       interval = mac->beacon.interval;
+       period = mac->beacon.period;
+       timeout = mac->beacon.last_update +
+                       msecs_to_jiffies(interval * 1024 / 1000) * 3;
+       spin_unlock_irq(&mac->lock);
+
+       if (interval > 0 && time_is_before_jiffies(timeout)) {
+               dev_dbg_f(zd_mac_dev(mac), "beacon interrupt stalled, "
+                                          "restarting. "
+                                          "(interval: %d, dtim: %d)\n",
+                                          interval, period);
+
+               zd_chip_disable_hwint(&mac->chip);
+
+               beacon = ieee80211_beacon_get(mac->hw, mac->vif);
+               if (beacon) {
+                       zd_mac_free_cur_beacon(mac);
+
+                       zd_mac_config_beacon(mac->hw, beacon, false);
+               }
+
+               zd_set_beacon_interval(&mac->chip, interval, period, mac->type);
+
+               zd_chip_enable_hwint(&mac->chip);
+
+               spin_lock_irq(&mac->lock);
+               mac->beacon.last_update = jiffies;
+               spin_unlock_irq(&mac->lock);
+       }
+
+rearm:
+       queue_delayed_work(zd_workqueue, &mac->beacon.watchdog_work,
+                          BEACON_WATCHDOG_DELAY);
+}
+
+static void beacon_init(struct zd_mac *mac)
+{
+       INIT_DELAYED_WORK(&mac->beacon.watchdog_work, beacon_watchdog_handler);
+}
+
+static void beacon_enable(struct zd_mac *mac)
+{
+       dev_dbg_f(zd_mac_dev(mac), "\n");
+
+       mac->beacon.last_update = jiffies;
+       queue_delayed_work(zd_workqueue, &mac->beacon.watchdog_work,
+                          BEACON_WATCHDOG_DELAY);
+}
+
+static void beacon_disable(struct zd_mac *mac)
+{
+       dev_dbg_f(zd_mac_dev(mac), "\n");
+       cancel_delayed_work_sync(&mac->beacon.watchdog_work);
+
+       zd_mac_free_cur_beacon(mac);
+}
+
+#define LINK_LED_WORK_DELAY HZ
+
+static void link_led_handler(struct work_struct *work)
+{
+       struct zd_mac *mac =
+               container_of(work, struct zd_mac, housekeeping.link_led_work.work);
+       struct zd_chip *chip = &mac->chip;
+       int is_associated;
+       int r;
+
+       if (!test_bit(ZD_DEVICE_RUNNING, &mac->flags))
+               goto requeue;
+
+       spin_lock_irq(&mac->lock);
+       is_associated = mac->associated;
+       spin_unlock_irq(&mac->lock);
+
+       r = zd_chip_control_leds(chip,
+                                is_associated ? ZD_LED_ASSOCIATED : ZD_LED_SCANNING);
+       if (r)
+               dev_dbg_f(zd_mac_dev(mac), "zd_chip_control_leds error %d\n", r);
+
+requeue:
+       queue_delayed_work(zd_workqueue, &mac->housekeeping.link_led_work,
+                          LINK_LED_WORK_DELAY);
+}
+
+static void housekeeping_init(struct zd_mac *mac)
+{
+       INIT_DELAYED_WORK(&mac->housekeeping.link_led_work, link_led_handler);
+}
+
+static void housekeeping_enable(struct zd_mac *mac)
+{
+       dev_dbg_f(zd_mac_dev(mac), "\n");
+       queue_delayed_work(zd_workqueue, &mac->housekeeping.link_led_work,
+                          0);
+}
+
+static void housekeeping_disable(struct zd_mac *mac)
+{
+       dev_dbg_f(zd_mac_dev(mac), "\n");
+       cancel_delayed_work_sync(&mac->housekeeping.link_led_work);
+       zd_chip_control_leds(&mac->chip, ZD_LED_OFF);
+}