// SPDX-License-Identifier: GPL-2.0-only
/******************************************************************************
 *
 * Copyright(c) 2008 - 2011 Intel Corporation. All rights reserved.
 *
 * Contact Information:
 *  Intel Linux Wireless <ilw@linux.intel.com>
 * Intel Corporation, 5200 N.E. Elam Young Parkway, Hillsboro, OR 97124-6497
 *****************************************************************************/

#include <linux/kernel.h>
#include <linux/module.h>
#include <linux/etherdevice.h>
#include <linux/sched.h>
#include <linux/slab.h>
#include <linux/types.h>
#include <linux/lockdep.h>
#include <linux/pci.h>
#include <linux/dma-mapping.h>
#include <linux/delay.h>
#include <linux/skbuff.h>
#include <net/mac80211.h>

#include "common.h"

int
_il_poll_bit(struct il_priv *il, u32 addr, u32 bits, u32 mask, int timeout)
{
        const int interval = 10; /* microseconds */
        int t = 0;

        do {
                if ((_il_rd(il, addr) & mask) == (bits & mask))
                        return t;
                udelay(interval);
                t += interval;
        } while (t < timeout);

        return -ETIMEDOUT;
}
EXPORT_SYMBOL(_il_poll_bit);

void
il_set_bit(struct il_priv *p, u32 r, u32 m)
{
        unsigned long reg_flags;

        spin_lock_irqsave(&p->reg_lock, reg_flags);
        _il_set_bit(p, r, m);
        spin_unlock_irqrestore(&p->reg_lock, reg_flags);
}
EXPORT_SYMBOL(il_set_bit);

void
il_clear_bit(struct il_priv *p, u32 r, u32 m)
{
        unsigned long reg_flags;

        spin_lock_irqsave(&p->reg_lock, reg_flags);
        _il_clear_bit(p, r, m);
        spin_unlock_irqrestore(&p->reg_lock, reg_flags);
}
EXPORT_SYMBOL(il_clear_bit);

bool
_il_grab_nic_access(struct il_priv *il)
{
        int ret;
        u32 val;

        /* this bit wakes up the NIC */
        _il_set_bit(il, CSR_GP_CNTRL, CSR_GP_CNTRL_REG_FLAG_MAC_ACCESS_REQ);

        /*
         * These bits say the device is running, and should keep running for
         * at least a short while (at least as long as MAC_ACCESS_REQ stays 1),
         * but they do not indicate that embedded SRAM is restored yet;
         * 3945 and 4965 have volatile SRAM, and must save/restore contents
         * to/from host DRAM when sleeping/waking for power-saving.
         * Each direction takes approximately 1/4 millisecond; with this
         * overhead, it's a good idea to grab and hold MAC_ACCESS_REQUEST if a
         * series of register accesses are expected (e.g. reading Event Log),
         * to keep device from sleeping.
         *
         * CSR_UCODE_DRV_GP1 register bit MAC_SLEEP == 0 indicates that
         * SRAM is okay/restored.  We don't check that here because this call
         * is just for hardware register access; but GP1 MAC_SLEEP check is a
         * good idea before accessing 3945/4965 SRAM (e.g. reading Event Log).
         *
         */
        ret =
            _il_poll_bit(il, CSR_GP_CNTRL, CSR_GP_CNTRL_REG_VAL_MAC_ACCESS_EN,
                         (CSR_GP_CNTRL_REG_FLAG_MAC_CLOCK_READY |
                          CSR_GP_CNTRL_REG_FLAG_GOING_TO_SLEEP), 15000);
        if (unlikely(ret < 0)) {
                val = _il_rd(il, CSR_GP_CNTRL);
                WARN_ONCE(1, "Timeout waiting for ucode processor access "
                             "(CSR_GP_CNTRL 0x%08x)\n", val);
                _il_wr(il, CSR_RESET, CSR_RESET_REG_FLAG_FORCE_NMI);
                return false;
        }

        return true;
}
EXPORT_SYMBOL_GPL(_il_grab_nic_access);

int
il_poll_bit(struct il_priv *il, u32 addr, u32 mask, int timeout)
{
        const int interval = 10; /* microseconds */
        int t = 0;

        do {
                if ((il_rd(il, addr) & mask) == mask)
                        return t;
                udelay(interval);
                t += interval;
        } while (t < timeout);

        return -ETIMEDOUT;
}
EXPORT_SYMBOL(il_poll_bit);

u32
il_rd_prph(struct il_priv *il, u32 reg)
{
        unsigned long reg_flags;
        u32 val;

        spin_lock_irqsave(&il->reg_lock, reg_flags);
        _il_grab_nic_access(il);
        val = _il_rd_prph(il, reg);
        _il_release_nic_access(il);
        spin_unlock_irqrestore(&il->reg_lock, reg_flags);
        return val;
}
EXPORT_SYMBOL(il_rd_prph);

void
il_wr_prph(struct il_priv *il, u32 addr, u32 val)
{
        unsigned long reg_flags;

        spin_lock_irqsave(&il->reg_lock, reg_flags);
        if (likely(_il_grab_nic_access(il))) {
                _il_wr_prph(il, addr, val);
                _il_release_nic_access(il);
        }
        spin_unlock_irqrestore(&il->reg_lock, reg_flags);
}
EXPORT_SYMBOL(il_wr_prph);

u32
il_read_targ_mem(struct il_priv *il, u32 addr)
{
        unsigned long reg_flags;
        u32 value;

        spin_lock_irqsave(&il->reg_lock, reg_flags);
        _il_grab_nic_access(il);

        _il_wr(il, HBUS_TARG_MEM_RADDR, addr);
        value = _il_rd(il, HBUS_TARG_MEM_RDAT);

        _il_release_nic_access(il);
        spin_unlock_irqrestore(&il->reg_lock, reg_flags);
        return value;
}
EXPORT_SYMBOL(il_read_targ_mem);

void
il_write_targ_mem(struct il_priv *il, u32 addr, u32 val)
{
        unsigned long reg_flags;

        spin_lock_irqsave(&il->reg_lock, reg_flags);
        if (likely(_il_grab_nic_access(il))) {
                _il_wr(il, HBUS_TARG_MEM_WADDR, addr);
                _il_wr(il, HBUS_TARG_MEM_WDAT, val);
                _il_release_nic_access(il);
        }
        spin_unlock_irqrestore(&il->reg_lock, reg_flags);
}
EXPORT_SYMBOL(il_write_targ_mem);

const char *
il_get_cmd_string(u8 cmd)
{
        switch (cmd) {
                IL_CMD(N_ALIVE);
                IL_CMD(N_ERROR);
                IL_CMD(C_RXON);
                IL_CMD(C_RXON_ASSOC);
                IL_CMD(C_QOS_PARAM);
                IL_CMD(C_RXON_TIMING);
                IL_CMD(C_ADD_STA);
                IL_CMD(C_REM_STA);
                IL_CMD(C_WEPKEY);
                IL_CMD(N_3945_RX);
                IL_CMD(C_TX);
                IL_CMD(C_RATE_SCALE);
                IL_CMD(C_LEDS);
                IL_CMD(C_TX_LINK_QUALITY_CMD);
                IL_CMD(C_CHANNEL_SWITCH);
                IL_CMD(N_CHANNEL_SWITCH);
                IL_CMD(C_SPECTRUM_MEASUREMENT);
                IL_CMD(N_SPECTRUM_MEASUREMENT);
                IL_CMD(C_POWER_TBL);
                IL_CMD(N_PM_SLEEP);
                IL_CMD(N_PM_DEBUG_STATS);
                IL_CMD(C_SCAN);
                IL_CMD(C_SCAN_ABORT);
                IL_CMD(N_SCAN_START);
                IL_CMD(N_SCAN_RESULTS);
                IL_CMD(N_SCAN_COMPLETE);
                IL_CMD(N_BEACON);
                IL_CMD(C_TX_BEACON);
                IL_CMD(C_TX_PWR_TBL);
                IL_CMD(C_BT_CONFIG);
                IL_CMD(C_STATS);
                IL_CMD(N_STATS);
                IL_CMD(N_CARD_STATE);
                IL_CMD(N_MISSED_BEACONS);
                IL_CMD(C_CT_KILL_CONFIG);
                IL_CMD(C_SENSITIVITY);
                IL_CMD(C_PHY_CALIBRATION);
                IL_CMD(N_RX_PHY);
                IL_CMD(N_RX_MPDU);
                IL_CMD(N_RX);
                IL_CMD(N_COMPRESSED_BA);
        default:
                return "UNKNOWN";

        }
}
EXPORT_SYMBOL(il_get_cmd_string);

#define HOST_COMPLETE_TIMEOUT (HZ / 2)

static void
il_generic_cmd_callback(struct il_priv *il, struct il_device_cmd *cmd,
                        struct il_rx_pkt *pkt)
{
        if (pkt->hdr.flags & IL_CMD_FAILED_MSK) {
                IL_ERR("Bad return from %s (0x%08X)\n",
                       il_get_cmd_string(cmd->hdr.cmd), pkt->hdr.flags);
                return;
        }
#ifdef CONFIG_IWLEGACY_DEBUG
        switch (cmd->hdr.cmd) {
        case C_TX_LINK_QUALITY_CMD:
        case C_SENSITIVITY:
                D_HC_DUMP("back from %s (0x%08X)\n",
                          il_get_cmd_string(cmd->hdr.cmd), pkt->hdr.flags);
                break;
        default:
                D_HC("back from %s (0x%08X)\n", il_get_cmd_string(cmd->hdr.cmd),
                     pkt->hdr.flags);
        }
#endif
}

static int
il_send_cmd_async(struct il_priv *il, struct il_host_cmd *cmd)
{
        int ret;

        BUG_ON(!(cmd->flags & CMD_ASYNC));

        /* An asynchronous command can not expect an SKB to be set. */
        BUG_ON(cmd->flags & CMD_WANT_SKB);

        /* Assign a generic callback if one is not provided */
        if (!cmd->callback)
                cmd->callback = il_generic_cmd_callback;

        if (test_bit(S_EXIT_PENDING, &il->status))
                return -EBUSY;

        ret = il_enqueue_hcmd(il, cmd);
        if (ret < 0) {
                IL_ERR("Error sending %s: enqueue_hcmd failed: %d\n",
                       il_get_cmd_string(cmd->id), ret);
                return ret;
        }
        return 0;
}

int
il_send_cmd_sync(struct il_priv *il, struct il_host_cmd *cmd)
{
        int cmd_idx;
        int ret;

        lockdep_assert_held(&il->mutex);

        BUG_ON(cmd->flags & CMD_ASYNC);

        /* A synchronous command can not have a callback set. */
        BUG_ON(cmd->callback);

        D_INFO("Attempting to send sync command %s\n",
               il_get_cmd_string(cmd->id));

        set_bit(S_HCMD_ACTIVE, &il->status);
        D_INFO("Setting HCMD_ACTIVE for command %s\n",
               il_get_cmd_string(cmd->id));

        cmd_idx = il_enqueue_hcmd(il, cmd);
        if (cmd_idx < 0) {
                ret = cmd_idx;
                IL_ERR("Error sending %s: enqueue_hcmd failed: %d\n",
                       il_get_cmd_string(cmd->id), ret);
                goto out;
        }

        ret = wait_event_timeout(il->wait_command_queue,
                                 !test_bit(S_HCMD_ACTIVE, &il->status),
                                 HOST_COMPLETE_TIMEOUT);
        if (!ret) {
                if (test_bit(S_HCMD_ACTIVE, &il->status)) {
                        IL_ERR("Error sending %s: time out after %dms.\n",
                               il_get_cmd_string(cmd->id),
                               jiffies_to_msecs(HOST_COMPLETE_TIMEOUT));

                        clear_bit(S_HCMD_ACTIVE, &il->status);
                        D_INFO("Clearing HCMD_ACTIVE for command %s\n",
                               il_get_cmd_string(cmd->id));
                        ret = -ETIMEDOUT;
                        goto cancel;
                }
        }

        if (test_bit(S_RFKILL, &il->status)) {
                IL_ERR("Command %s aborted: RF KILL Switch\n",
                       il_get_cmd_string(cmd->id));
                ret = -ECANCELED;
                goto fail;
        }
        if (test_bit(S_FW_ERROR, &il->status)) {
                IL_ERR("Command %s failed: FW Error\n",
                       il_get_cmd_string(cmd->id));
                ret = -EIO;
                goto fail;
        }
        if ((cmd->flags & CMD_WANT_SKB) && !cmd->reply_page) {
                IL_ERR("Error: Response NULL in '%s'\n",
                       il_get_cmd_string(cmd->id));
                ret = -EIO;
                goto cancel;
        }

        ret = 0;
        goto out;

cancel:
        if (cmd->flags & CMD_WANT_SKB) {
                /*
                 * Cancel the CMD_WANT_SKB flag for the cmd in the
                 * TX cmd queue. Otherwise in case the cmd comes
                 * in later, it will possibly set an invalid
                 * address (cmd->meta.source).
                 */
                il->txq[il->cmd_queue].meta[cmd_idx].flags &= ~CMD_WANT_SKB;
        }
fail:
        if (cmd->reply_page) {
                il_free_pages(il, cmd->reply_page);
                cmd->reply_page = 0;
        }
out:
        return ret;
}
EXPORT_SYMBOL(il_send_cmd_sync);

int
il_send_cmd(struct il_priv *il, struct il_host_cmd *cmd)
{
        if (cmd->flags & CMD_ASYNC)
                return il_send_cmd_async(il, cmd);

        return il_send_cmd_sync(il, cmd);
}
EXPORT_SYMBOL(il_send_cmd);

int
il_send_cmd_pdu(struct il_priv *il, u8 id, u16 len, const void *data)
{
        struct il_host_cmd cmd = {
                .id = id,
                .len = len,
                .data = data,
        };

        return il_send_cmd_sync(il, &cmd);
}
EXPORT_SYMBOL(il_send_cmd_pdu);

int
il_send_cmd_pdu_async(struct il_priv *il, u8 id, u16 len, const void *data,
                      void (*callback) (struct il_priv *il,
                                        struct il_device_cmd *cmd,
                                        struct il_rx_pkt *pkt))
{
        struct il_host_cmd cmd = {
                .id = id,
                .len = len,
                .data = data,
        };

        cmd.flags |= CMD_ASYNC;
        cmd.callback = callback;

        return il_send_cmd_async(il, &cmd);
}
EXPORT_SYMBOL(il_send_cmd_pdu_async);

/* default: IL_LED_BLINK(0) using blinking idx table */
static int led_mode;
module_param(led_mode, int, 0444);
MODULE_PARM_DESC(led_mode,
                 "0=system default, " "1=On(RF On)/Off(RF Off), 2=blinking");

/* Throughput           OFF time(ms)    ON time (ms)
 *      >300                    25              25
 *      >200 to 300             40              40
 *      >100 to 200             55              55
 *      >70 to 100              65              65
 *      >50 to 70               75              75
 *      >20 to 50               85              85
 *      >10 to 20               95              95
 *      >5 to 10                110             110
 *      >1 to 5                 130             130
 *      >0 to 1                 167             167
 *      <=0                                     SOLID ON
 */
static const struct ieee80211_tpt_blink il_blink[] = {
        {.throughput = 0,               .blink_time = 334},
        {.throughput = 1 * 1024 - 1,    .blink_time = 260},
        {.throughput = 5 * 1024 - 1,    .blink_time = 220},
        {.throughput = 10 * 1024 - 1,   .blink_time = 190},
        {.throughput = 20 * 1024 - 1,   .blink_time = 170},
        {.throughput = 50 * 1024 - 1,   .blink_time = 150},
        {.throughput = 70 * 1024 - 1,   .blink_time = 130},
        {.throughput = 100 * 1024 - 1,  .blink_time = 110},
        {.throughput = 200 * 1024 - 1,  .blink_time = 80},
        {.throughput = 300 * 1024 - 1,  .blink_time = 50},
};

/*
 * Adjust led blink rate to compensate on a MAC Clock difference on every HW
 * Led blink rate analysis showed an average deviation of 0% on 3945,
 * 5% on 4965 HW.
 * Need to compensate on the led on/off time per HW according to the deviation
 * to achieve the desired led frequency
 * The calculation is: (100-averageDeviation)/100 * blinkTime
 * For code efficiency the calculation will be:
 *     compensation = (100 - averageDeviation) * 64 / 100
 *     NewBlinkTime = (compensation * BlinkTime) / 64
 */
static inline u8
il_blink_compensation(struct il_priv *il, u8 time, u16 compensation)
{
        if (!compensation) {
                IL_ERR("undefined blink compensation: "
                       "use pre-defined blinking time\n");
                return time;
        }

        return (u8) ((time * compensation) >> 6);
}

/* Set led pattern command */
static int
il_led_cmd(struct il_priv *il, unsigned long on, unsigned long off)
{
        struct il_led_cmd led_cmd = {
                .id = IL_LED_LINK,
                .interval = IL_DEF_LED_INTRVL
        };
        int ret;

        if (!test_bit(S_READY, &il->status))
                return -EBUSY;

        if (il->blink_on == on && il->blink_off == off)
                return 0;

        if (off == 0) {
                /* led is SOLID_ON */
                on = IL_LED_SOLID;
        }

        D_LED("Led blink time compensation=%u\n",
              il->cfg->led_compensation);
        led_cmd.on =
            il_blink_compensation(il, on,
                                  il->cfg->led_compensation);
        led_cmd.off =
            il_blink_compensation(il, off,
                                  il->cfg->led_compensation);

        ret = il->ops->send_led_cmd(il, &led_cmd);
        if (!ret) {
                il->blink_on = on;
                il->blink_off = off;
        }
        return ret;
}

static void
il_led_brightness_set(struct led_classdev *led_cdev,
                      enum led_brightness brightness)
{
        struct il_priv *il = container_of(led_cdev, struct il_priv, led);
        unsigned long on = 0;

        if (brightness > 0)
                on = IL_LED_SOLID;

        il_led_cmd(il, on, 0);
}

static int
il_led_blink_set(struct led_classdev *led_cdev, unsigned long *delay_on,
                 unsigned long *delay_off)
{
        struct il_priv *il = container_of(led_cdev, struct il_priv, led);

        return il_led_cmd(il, *delay_on, *delay_off);
}

void
il_leds_init(struct il_priv *il)
{
        int mode = led_mode;
        int ret;

        if (mode == IL_LED_DEFAULT)
                mode = il->cfg->led_mode;

        il->led.name =
            kasprintf(GFP_KERNEL, "%s-led", wiphy_name(il->hw->wiphy));
        il->led.brightness_set = il_led_brightness_set;
        il->led.blink_set = il_led_blink_set;
        il->led.max_brightness = 1;

        switch (mode) {
        case IL_LED_DEFAULT:
                WARN_ON(1);
                break;
        case IL_LED_BLINK:
                il->led.default_trigger =
                    ieee80211_create_tpt_led_trigger(il->hw,
                                                     IEEE80211_TPT_LEDTRIG_FL_CONNECTED,
                                                     il_blink,
                                                     ARRAY_SIZE(il_blink));
                break;
        case IL_LED_RF_STATE:
                il->led.default_trigger = ieee80211_get_radio_led_name(il->hw);
                break;
        }

        ret = led_classdev_register(&il->pci_dev->dev, &il->led);
        if (ret) {
                kfree(il->led.name);
                return;
        }

        il->led_registered = true;
}
EXPORT_SYMBOL(il_leds_init);

void
il_leds_exit(struct il_priv *il)
{
        if (!il->led_registered)
                return;

        led_classdev_unregister(&il->led);
        kfree(il->led.name);
}
EXPORT_SYMBOL(il_leds_exit);

/************************** EEPROM BANDS ****************************
 *
 * The il_eeprom_band definitions below provide the mapping from the
 * EEPROM contents to the specific channel number supported for each
 * band.
 *
 * For example, il_priv->eeprom.band_3_channels[4] from the band_3
 * definition below maps to physical channel 42 in the 5.2GHz spectrum.
 * The specific geography and calibration information for that channel
 * is contained in the eeprom map itself.
 *
 * During init, we copy the eeprom information and channel map
 * information into il->channel_info_24/52 and il->channel_map_24/52
 *
 * channel_map_24/52 provides the idx in the channel_info array for a
 * given channel.  We have to have two separate maps as there is channel
 * overlap with the 2.4GHz and 5.2GHz spectrum as seen in band_1 and
 * band_2
 *
 * A value of 0xff stored in the channel_map indicates that the channel
 * is not supported by the hardware at all.
 *
 * A value of 0xfe in the channel_map indicates that the channel is not
 * valid for Tx with the current hardware.  This means that
 * while the system can tune and receive on a given channel, it may not
 * be able to associate or transmit any frames on that
 * channel.  There is no corresponding channel information for that
 * entry.
 *
 *********************************************************************/

/* 2.4 GHz */
const u8 il_eeprom_band_1[14] = {
        1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, 14
};

/* 5.2 GHz bands */
static const u8 il_eeprom_band_2[] = {  /* 4915-5080MHz */
        183, 184, 185, 187, 188, 189, 192, 196, 7, 8, 11, 12, 16
};

static const u8 il_eeprom_band_3[] = {  /* 5170-5320MHz */
        34, 36, 38, 40, 42, 44, 46, 48, 52, 56, 60, 64
};

static const u8 il_eeprom_band_4[] = {  /* 5500-5700MHz */
        100, 104, 108, 112, 116, 120, 124, 128, 132, 136, 140
};

static const u8 il_eeprom_band_5[] = {  /* 5725-5825MHz */
        145, 149, 153, 157, 161, 165
};

static const u8 il_eeprom_band_6[] = {  /* 2.4 ht40 channel */
        1, 2, 3, 4, 5, 6, 7
};

static const u8 il_eeprom_band_7[] = {  /* 5.2 ht40 channel */
        36, 44, 52, 60, 100, 108, 116, 124, 132, 149, 157
};

/******************************************************************************
 *
 * EEPROM related functions
 *
******************************************************************************/

static int
il_eeprom_verify_signature(struct il_priv *il)
{
        u32 gp = _il_rd(il, CSR_EEPROM_GP) & CSR_EEPROM_GP_VALID_MSK;
        int ret = 0;

        D_EEPROM("EEPROM signature=0x%08x\n", gp);
        switch (gp) {
        case CSR_EEPROM_GP_GOOD_SIG_EEP_LESS_THAN_4K:
        case CSR_EEPROM_GP_GOOD_SIG_EEP_MORE_THAN_4K:
                break;
        default:
                IL_ERR("bad EEPROM signature," "EEPROM_GP=0x%08x\n", gp);
                ret = -ENOENT;
                break;
        }
        return ret;
}

const u8 *
il_eeprom_query_addr(const struct il_priv *il, size_t offset)
{
        BUG_ON(offset >= il->cfg->eeprom_size);
        return &il->eeprom[offset];
}
EXPORT_SYMBOL(il_eeprom_query_addr);

u16
il_eeprom_query16(const struct il_priv *il, size_t offset)
{
        if (!il->eeprom)
                return 0;
        return (u16) il->eeprom[offset] | ((u16) il->eeprom[offset + 1] << 8);
}
EXPORT_SYMBOL(il_eeprom_query16);

/**
 * il_eeprom_init - read EEPROM contents
 *
 * Load the EEPROM contents from adapter into il->eeprom
 *
 * NOTE:  This routine uses the non-debug IO access functions.
 */
int
il_eeprom_init(struct il_priv *il)
{
        __le16 *e;
        u32 gp = _il_rd(il, CSR_EEPROM_GP);
        int sz;
        int ret;
        u16 addr;

        /* allocate eeprom */
        sz = il->cfg->eeprom_size;
        D_EEPROM("NVM size = %d\n", sz);
        il->eeprom = kzalloc(sz, GFP_KERNEL);
        if (!il->eeprom)
                return -ENOMEM;

        e = (__le16 *) il->eeprom;

        il->ops->apm_init(il);

        ret = il_eeprom_verify_signature(il);
        if (ret < 0) {
                IL_ERR("EEPROM not found, EEPROM_GP=0x%08x\n", gp);
                ret = -ENOENT;
                goto err;
        }

        /* Make sure driver (instead of uCode) is allowed to read EEPROM */
        ret = il->ops->eeprom_acquire_semaphore(il);
        if (ret < 0) {
                IL_ERR("Failed to acquire EEPROM semaphore.\n");
                ret = -ENOENT;
                goto err;
        }

        /* eeprom is an array of 16bit values */
        for (addr = 0; addr < sz; addr += sizeof(u16)) {
                u32 r;

                _il_wr(il, CSR_EEPROM_REG,
                       CSR_EEPROM_REG_MSK_ADDR & (addr << 1));

                ret =
                    _il_poll_bit(il, CSR_EEPROM_REG,
                                 CSR_EEPROM_REG_READ_VALID_MSK,
                                 CSR_EEPROM_REG_READ_VALID_MSK,
                                 IL_EEPROM_ACCESS_TIMEOUT);
                if (ret < 0) {
                        IL_ERR("Time out reading EEPROM[%d]\n", addr);
                        goto done;
                }
                r = _il_rd(il, CSR_EEPROM_REG);
                e[addr / 2] = cpu_to_le16(r >> 16);
        }

        D_EEPROM("NVM Type: %s, version: 0x%x\n", "EEPROM",
                 il_eeprom_query16(il, EEPROM_VERSION));

        ret = 0;
done:
        il->ops->eeprom_release_semaphore(il);

err:
        if (ret)
                il_eeprom_free(il);
        /* Reset chip to save power until we load uCode during "up". */
        il_apm_stop(il);
        return ret;
}
EXPORT_SYMBOL(il_eeprom_init);

void
il_eeprom_free(struct il_priv *il)
{
        kfree(il->eeprom);
        il->eeprom = NULL;
}
EXPORT_SYMBOL(il_eeprom_free);

static void
il_init_band_reference(const struct il_priv *il, int eep_band,
                       int *eeprom_ch_count,
                       const struct il_eeprom_channel **eeprom_ch_info,
                       const u8 **eeprom_ch_idx)
{
        u32 offset = il->cfg->regulatory_bands[eep_band - 1];

        switch (eep_band) {
        case 1:         /* 2.4GHz band */
                *eeprom_ch_count = ARRAY_SIZE(il_eeprom_band_1);
                *eeprom_ch_info =
                    (struct il_eeprom_channel *)il_eeprom_query_addr(il,
                                                                     offset);
                *eeprom_ch_idx = il_eeprom_band_1;
                break;
        case 2:         /* 4.9GHz band */
                *eeprom_ch_count = ARRAY_SIZE(il_eeprom_band_2);
                *eeprom_ch_info =
                    (struct il_eeprom_channel *)il_eeprom_query_addr(il,
                                                                     offset);
                *eeprom_ch_idx = il_eeprom_band_2;
                break;
        case 3:         /* 5.2GHz band */
                *eeprom_ch_count = ARRAY_SIZE(il_eeprom_band_3);
                *eeprom_ch_info =
                    (struct il_eeprom_channel *)il_eeprom_query_addr(il,
                                                                     offset);
                *eeprom_ch_idx = il_eeprom_band_3;
                break;
        case 4:         /* 5.5GHz band */
                *eeprom_ch_count = ARRAY_SIZE(il_eeprom_band_4);
                *eeprom_ch_info =
                    (struct il_eeprom_channel *)il_eeprom_query_addr(il,
                                                                     offset);
                *eeprom_ch_idx = il_eeprom_band_4;
                break;
        case 5:         /* 5.7GHz band */
                *eeprom_ch_count = ARRAY_SIZE(il_eeprom_band_5);
                *eeprom_ch_info =
                    (struct il_eeprom_channel *)il_eeprom_query_addr(il,
                                                                     offset);
                *eeprom_ch_idx = il_eeprom_band_5;
                break;
        case 6:         /* 2.4GHz ht40 channels */
                *eeprom_ch_count = ARRAY_SIZE(il_eeprom_band_6);
                *eeprom_ch_info =
                    (struct il_eeprom_channel *)il_eeprom_query_addr(il,
                                                                     offset);
                *eeprom_ch_idx = il_eeprom_band_6;
                break;
        case 7:         /* 5 GHz ht40 channels */
                *eeprom_ch_count = ARRAY_SIZE(il_eeprom_band_7);
                *eeprom_ch_info =
                    (struct il_eeprom_channel *)il_eeprom_query_addr(il,
                                                                     offset);
                *eeprom_ch_idx = il_eeprom_band_7;
                break;
        default:
                BUG();
        }
}

#define CHECK_AND_PRINT(x) ((eeprom_ch->flags & EEPROM_CHANNEL_##x) \
                            ? # x " " : "")
/**
 * il_mod_ht40_chan_info - Copy ht40 channel info into driver's il.
 *
 * Does not set up a command, or touch hardware.
 */
static int
il_mod_ht40_chan_info(struct il_priv *il, enum nl80211_band band, u16 channel,
                      const struct il_eeprom_channel *eeprom_ch,
                      u8 clear_ht40_extension_channel)
{
        struct il_channel_info *ch_info;

        ch_info =
            (struct il_channel_info *)il_get_channel_info(il, band, channel);

        if (!il_is_channel_valid(ch_info))
                return -1;

        D_EEPROM("HT40 Ch. %d [%sGHz] %s%s%s%s%s(0x%02x %ddBm):"
                 " Ad-Hoc %ssupported\n", ch_info->channel,
                 il_is_channel_a_band(ch_info) ? "5.2" : "2.4",
                 CHECK_AND_PRINT(IBSS), CHECK_AND_PRINT(ACTIVE),
                 CHECK_AND_PRINT(RADAR), CHECK_AND_PRINT(WIDE),
                 CHECK_AND_PRINT(DFS), eeprom_ch->flags,
                 eeprom_ch->max_power_avg,
                 ((eeprom_ch->flags & EEPROM_CHANNEL_IBSS) &&
                  !(eeprom_ch->flags & EEPROM_CHANNEL_RADAR)) ? "" : "not ");

        ch_info->ht40_eeprom = *eeprom_ch;
        ch_info->ht40_max_power_avg = eeprom_ch->max_power_avg;
        ch_info->ht40_flags = eeprom_ch->flags;
        if (eeprom_ch->flags & EEPROM_CHANNEL_VALID)
                ch_info->ht40_extension_channel &=
                    ~clear_ht40_extension_channel;

        return 0;
}

#define CHECK_AND_PRINT_I(x) ((eeprom_ch_info[ch].flags & EEPROM_CHANNEL_##x) \
                            ? # x " " : "")

/**
 * il_init_channel_map - Set up driver's info for all possible channels
 */
int
il_init_channel_map(struct il_priv *il)
{
        int eeprom_ch_count = 0;
        const u8 *eeprom_ch_idx = NULL;
        const struct il_eeprom_channel *eeprom_ch_info = NULL;
        int band, ch;
        struct il_channel_info *ch_info;

        if (il->channel_count) {
                D_EEPROM("Channel map already initialized.\n");
                return 0;
        }

        D_EEPROM("Initializing regulatory info from EEPROM\n");

        il->channel_count =
            ARRAY_SIZE(il_eeprom_band_1) + ARRAY_SIZE(il_eeprom_band_2) +
            ARRAY_SIZE(il_eeprom_band_3) + ARRAY_SIZE(il_eeprom_band_4) +
            ARRAY_SIZE(il_eeprom_band_5);

        D_EEPROM("Parsing data for %d channels.\n", il->channel_count);

        il->channel_info =
            kcalloc(il->channel_count, sizeof(struct il_channel_info),
                    GFP_KERNEL);
        if (!il->channel_info) {
                IL_ERR("Could not allocate channel_info\n");
                il->channel_count = 0;
                return -ENOMEM;
        }

        ch_info = il->channel_info;

        /* Loop through the 5 EEPROM bands adding them in order to the
         * channel map we maintain (that contains additional information than
         * what just in the EEPROM) */
        for (band = 1; band <= 5; band++) {

                il_init_band_reference(il, band, &eeprom_ch_count,
                                       &eeprom_ch_info, &eeprom_ch_idx);

                /* Loop through each band adding each of the channels */
                for (ch = 0; ch < eeprom_ch_count; ch++) {
                        ch_info->channel = eeprom_ch_idx[ch];
                        ch_info->band =
                            (band ==
                             1) ? NL80211_BAND_2GHZ : NL80211_BAND_5GHZ;

                        /* permanently store EEPROM's channel regulatory flags
                         *   and max power in channel info database. */
                        ch_info->eeprom = eeprom_ch_info[ch];

                        /* Copy the run-time flags so they are there even on
                         * invalid channels */
                        ch_info->flags = eeprom_ch_info[ch].flags;
                        /* First write that ht40 is not enabled, and then enable
                         * one by one */
                        ch_info->ht40_extension_channel =
                            IEEE80211_CHAN_NO_HT40;

                        if (!(il_is_channel_valid(ch_info))) {
                                D_EEPROM("Ch. %d Flags %x [%sGHz] - "
                                         "No traffic\n", ch_info->channel,
                                         ch_info->flags,
                                         il_is_channel_a_band(ch_info) ? "5.2" :
                                         "2.4");
                                ch_info++;
                                continue;
                        }

                        /* Initialize regulatory-based run-time data */
                        ch_info->max_power_avg = ch_info->curr_txpow =
                            eeprom_ch_info[ch].max_power_avg;
                        ch_info->scan_power = eeprom_ch_info[ch].max_power_avg;
                        ch_info->min_power = 0;

                        D_EEPROM("Ch. %d [%sGHz] " "%s%s%s%s%s%s(0x%02x %ddBm):"
                                 " Ad-Hoc %ssupported\n", ch_info->channel,
                                 il_is_channel_a_band(ch_info) ? "5.2" : "2.4",
                                 CHECK_AND_PRINT_I(VALID),
                                 CHECK_AND_PRINT_I(IBSS),
                                 CHECK_AND_PRINT_I(ACTIVE),
                                 CHECK_AND_PRINT_I(RADAR),
                                 CHECK_AND_PRINT_I(WIDE),
                                 CHECK_AND_PRINT_I(DFS),
                                 eeprom_ch_info[ch].flags,
                                 eeprom_ch_info[ch].max_power_avg,
                                 ((eeprom_ch_info[ch].
                                   flags & EEPROM_CHANNEL_IBSS) &&
                                  !(eeprom_ch_info[ch].
                                    flags & EEPROM_CHANNEL_RADAR)) ? "" :
                                 "not ");

                        ch_info++;
                }
        }

        /* Check if we do have HT40 channels */
        if (il->cfg->regulatory_bands[5] == EEPROM_REGULATORY_BAND_NO_HT40 &&
            il->cfg->regulatory_bands[6] == EEPROM_REGULATORY_BAND_NO_HT40)
                return 0;

        /* Two additional EEPROM bands for 2.4 and 5 GHz HT40 channels */
        for (band = 6; band <= 7; band++) {
                enum nl80211_band ieeeband;

                il_init_band_reference(il, band, &eeprom_ch_count,
                                       &eeprom_ch_info, &eeprom_ch_idx);

                /* EEPROM band 6 is 2.4, band 7 is 5 GHz */
                ieeeband =
                    (band == 6) ? NL80211_BAND_2GHZ : NL80211_BAND_5GHZ;

                /* Loop through each band adding each of the channels */
                for (ch = 0; ch < eeprom_ch_count; ch++) {
                        /* Set up driver's info for lower half */
                        il_mod_ht40_chan_info(il, ieeeband, eeprom_ch_idx[ch],

                                              &eeprom_ch_info[ch],
                                              IEEE80211_CHAN_NO_HT40PLUS);

                        /* Set up driver's info for upper half */
                        il_mod_ht40_chan_info(il, ieeeband,
                                              eeprom_ch_idx[ch] + 4,
                                              &eeprom_ch_info[ch],
                                              IEEE80211_CHAN_NO_HT40MINUS);
                }
        }

        return 0;
}
EXPORT_SYMBOL(il_init_channel_map);

/*
 * il_free_channel_map - undo allocations in il_init_channel_map
 */
void
il_free_channel_map(struct il_priv *il)
{
        kfree(il->channel_info);
        il->channel_count = 0;
}
EXPORT_SYMBOL(il_free_channel_map);

/**
 * il_get_channel_info - Find driver's ilate channel info
 *
 * Based on band and channel number.
 */
const struct il_channel_info *
il_get_channel_info(const struct il_priv *il, enum nl80211_band band,
                    u16 channel)
{
        int i;

        switch (band) {
        case NL80211_BAND_5GHZ:
                for (i = 14; i < il->channel_count; i++) {
                        if (il->channel_info[i].channel == channel)
                                return &il->channel_info[i];
                }
                break;
        case NL80211_BAND_2GHZ:
                if (channel >= 1 && channel <= 14)
                        return &il->channel_info[channel - 1];
                break;
        default:
                BUG();
        }

        return NULL;
}
EXPORT_SYMBOL(il_get_channel_info);

/*
 * Setting power level allows the card to go to sleep when not busy.
 *
 * We calculate a sleep command based on the required latency, which
 * we get from mac80211.
 */

#define SLP_VEC(X0, X1, X2, X3, X4) { \
                cpu_to_le32(X0), \
                cpu_to_le32(X1), \
                cpu_to_le32(X2), \
                cpu_to_le32(X3), \
                cpu_to_le32(X4)  \
}

static void
il_build_powertable_cmd(struct il_priv *il, struct il_powertable_cmd *cmd)
{
        const __le32 interval[3][IL_POWER_VEC_SIZE] = {
                SLP_VEC(2, 2, 4, 6, 0xFF),
                SLP_VEC(2, 4, 7, 10, 10),
                SLP_VEC(4, 7, 10, 10, 0xFF)
        };
        int i, dtim_period, no_dtim;
        u32 max_sleep;
        bool skip;

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

        if (il->power_data.pci_pm)
                cmd->flags |= IL_POWER_PCI_PM_MSK;

        /* if no Power Save, we are done */
        if (il->power_data.ps_disabled)
                return;

        cmd->flags = IL_POWER_DRIVER_ALLOW_SLEEP_MSK;
        cmd->keep_alive_seconds = 0;
        cmd->debug_flags = 0;
        cmd->rx_data_timeout = cpu_to_le32(25 * 1024);
        cmd->tx_data_timeout = cpu_to_le32(25 * 1024);
        cmd->keep_alive_beacons = 0;

        dtim_period = il->vif ? il->vif->bss_conf.dtim_period : 0;

        if (dtim_period <= 2) {
                memcpy(cmd->sleep_interval, interval[0], sizeof(interval[0]));
                no_dtim = 2;
        } else if (dtim_period <= 10) {
                memcpy(cmd->sleep_interval, interval[1], sizeof(interval[1]));
                no_dtim = 2;
        } else {
                memcpy(cmd->sleep_interval, interval[2], sizeof(interval[2]));
                no_dtim = 0;
        }

        if (dtim_period == 0) {
                dtim_period = 1;
                skip = false;
        } else {
                skip = !!no_dtim;
        }

        if (skip) {
                __le32 tmp = cmd->sleep_interval[IL_POWER_VEC_SIZE - 1];

                max_sleep = le32_to_cpu(tmp);
                if (max_sleep == 0xFF)
                        max_sleep = dtim_period * (skip + 1);
                else if (max_sleep >  dtim_period)
                        max_sleep = (max_sleep / dtim_period) * dtim_period;
                cmd->flags |= IL_POWER_SLEEP_OVER_DTIM_MSK;
        } else {
                max_sleep = dtim_period;
                cmd->flags &= ~IL_POWER_SLEEP_OVER_DTIM_MSK;
        }

        for (i = 0; i < IL_POWER_VEC_SIZE; i++)
                if (le32_to_cpu(cmd->sleep_interval[i]) > max_sleep)
                        cmd->sleep_interval[i] = cpu_to_le32(max_sleep);
}

static int
il_set_power(struct il_priv *il, struct il_powertable_cmd *cmd)
{
        D_POWER("Sending power/sleep command\n");
        D_POWER("Flags value = 0x%08X\n", cmd->flags);
        D_POWER("Tx timeout = %u\n", le32_to_cpu(cmd->tx_data_timeout));
        D_POWER("Rx timeout = %u\n", le32_to_cpu(cmd->rx_data_timeout));
        D_POWER("Sleep interval vector = { %d , %d , %d , %d , %d }\n",
                le32_to_cpu(cmd->sleep_interval[0]),
                le32_to_cpu(cmd->sleep_interval[1]),
                le32_to_cpu(cmd->sleep_interval[2]),
                le32_to_cpu(cmd->sleep_interval[3]),
                le32_to_cpu(cmd->sleep_interval[4]));

        return il_send_cmd_pdu(il, C_POWER_TBL,
                               sizeof(struct il_powertable_cmd), cmd);
}

static int
il_power_set_mode(struct il_priv *il, struct il_powertable_cmd *cmd, bool force)
{
        int ret;
        bool update_chains;

        lockdep_assert_held(&il->mutex);

        /* Don't update the RX chain when chain noise calibration is running */
        update_chains = il->chain_noise_data.state == IL_CHAIN_NOISE_DONE ||
            il->chain_noise_data.state == IL_CHAIN_NOISE_ALIVE;

        if (!memcmp(&il->power_data.sleep_cmd, cmd, sizeof(*cmd)) && !force)
                return 0;

        if (!il_is_ready_rf(il))
                return -EIO;

        /* scan complete use sleep_power_next, need to be updated */
        memcpy(&il->power_data.sleep_cmd_next, cmd, sizeof(*cmd));
        if (test_bit(S_SCANNING, &il->status) && !force) {
                D_INFO("Defer power set mode while scanning\n");
                return 0;
        }

        if (cmd->flags & IL_POWER_DRIVER_ALLOW_SLEEP_MSK)
                set_bit(S_POWER_PMI, &il->status);

        ret = il_set_power(il, cmd);
        if (!ret) {
                if (!(cmd->flags & IL_POWER_DRIVER_ALLOW_SLEEP_MSK))
                        clear_bit(S_POWER_PMI, &il->status);

                if (il->ops->update_chain_flags && update_chains)
                        il->ops->update_chain_flags(il);
                else if (il->ops->update_chain_flags)
                        D_POWER("Cannot update the power, chain noise "
                                "calibration running: %d\n",
                                il->chain_noise_data.state);

                memcpy(&il->power_data.sleep_cmd, cmd, sizeof(*cmd));
        } else
                IL_ERR("set power fail, ret = %d", ret);

        return ret;
}

int
il_power_update_mode(struct il_priv *il, bool force)
{
        struct il_powertable_cmd cmd;

        il_build_powertable_cmd(il, &cmd);

        return il_power_set_mode(il, &cmd, force);
}
EXPORT_SYMBOL(il_power_update_mode);

/* initialize to default */
void
il_power_initialize(struct il_priv *il)
{
        u16 lctl;

        pcie_capability_read_word(il->pci_dev, PCI_EXP_LNKCTL, &lctl);
        il->power_data.pci_pm = !(lctl & PCI_EXP_LNKCTL_ASPM_L0S);

        il->power_data.debug_sleep_level_override = -1;

        memset(&il->power_data.sleep_cmd, 0, sizeof(il->power_data.sleep_cmd));
}
EXPORT_SYMBOL(il_power_initialize);

/* For active scan, listen ACTIVE_DWELL_TIME (msec) on each channel after
 * sending probe req.  This should be set long enough to hear probe responses
 * from more than one AP.  */
#define IL_ACTIVE_DWELL_TIME_24    (30) /* all times in msec */
#define IL_ACTIVE_DWELL_TIME_52    (20)

#define IL_ACTIVE_DWELL_FACTOR_24GHZ (3)
#define IL_ACTIVE_DWELL_FACTOR_52GHZ (2)

/* For passive scan, listen PASSIVE_DWELL_TIME (msec) on each channel.
 * Must be set longer than active dwell time.
 * For the most reliable scan, set > AP beacon interval (typically 100msec). */
#define IL_PASSIVE_DWELL_TIME_24   (20) /* all times in msec */
#define IL_PASSIVE_DWELL_TIME_52   (10)
#define IL_PASSIVE_DWELL_BASE      (100)
#define IL_CHANNEL_TUNE_TIME       5

static int
il_send_scan_abort(struct il_priv *il)
{
        int ret;
        struct il_rx_pkt *pkt;
        struct il_host_cmd cmd = {
                .id = C_SCAN_ABORT,
                .flags = CMD_WANT_SKB,
        };

        /* Exit instantly with error when device is not ready
         * to receive scan abort command or it does not perform
         * hardware scan currently */
        if (!test_bit(S_READY, &il->status) ||
            !test_bit(S_GEO_CONFIGURED, &il->status) ||
            !test_bit(S_SCAN_HW, &il->status) ||
            test_bit(S_FW_ERROR, &il->status) ||
            test_bit(S_EXIT_PENDING, &il->status))
                return -EIO;

        ret = il_send_cmd_sync(il, &cmd);
        if (ret)
                return ret;

        pkt = (struct il_rx_pkt *)cmd.reply_page;
        if (pkt->u.status != CAN_ABORT_STATUS) {
                /* The scan abort will return 1 for success or
                 * 2 for "failure".  A failure condition can be
                 * due to simply not being in an active scan which
                 * can occur if we send the scan abort before we
                 * the microcode has notified us that a scan is
                 * completed. */
                D_SCAN("SCAN_ABORT ret %d.\n", pkt->u.status);
                ret = -EIO;
        }

        il_free_pages(il, cmd.reply_page);
        return ret;
}

static void
il_complete_scan(struct il_priv *il, bool aborted)
{
        struct cfg80211_scan_info info = {
                .aborted = aborted,
        };

        /* check if scan was requested from mac80211 */
        if (il->scan_request) {
                D_SCAN("Complete scan in mac80211\n");
                ieee80211_scan_completed(il->hw, &info);
        }

        il->scan_vif = NULL;
        il->scan_request = NULL;
}

void
il_force_scan_end(struct il_priv *il)
{
        lockdep_assert_held(&il->mutex);

        if (!test_bit(S_SCANNING, &il->status)) {
                D_SCAN("Forcing scan end while not scanning\n");
                return;
        }

        D_SCAN("Forcing scan end\n");
        clear_bit(S_SCANNING, &il->status);
        clear_bit(S_SCAN_HW, &il->status);
        clear_bit(S_SCAN_ABORTING, &il->status);
        il_complete_scan(il, true);
}

static void
il_do_scan_abort(struct il_priv *il)
{
        int ret;

        lockdep_assert_held(&il->mutex);

        if (!test_bit(S_SCANNING, &il->status)) {
                D_SCAN("Not performing scan to abort\n");
                return;
        }

        if (test_and_set_bit(S_SCAN_ABORTING, &il->status)) {
                D_SCAN("Scan abort in progress\n");
                return;
        }

        ret = il_send_scan_abort(il);
        if (ret) {
                D_SCAN("Send scan abort failed %d\n", ret);
                il_force_scan_end(il);
        } else
                D_SCAN("Successfully send scan abort\n");
}

/**
 * il_scan_cancel - Cancel any currently executing HW scan
 */
int
il_scan_cancel(struct il_priv *il)
{
        D_SCAN("Queuing abort scan\n");
        queue_work(il->workqueue, &il->abort_scan);
        return 0;
}
EXPORT_SYMBOL(il_scan_cancel);

/**
 * il_scan_cancel_timeout - Cancel any currently executing HW scan
 * @ms: amount of time to wait (in milliseconds) for scan to abort
 *
 */
int
il_scan_cancel_timeout(struct il_priv *il, unsigned long ms)
{
        unsigned long timeout = jiffies + msecs_to_jiffies(ms);

        lockdep_assert_held(&il->mutex);

        D_SCAN("Scan cancel timeout\n");

        il_do_scan_abort(il);

        while (time_before_eq(jiffies, timeout)) {
                if (!test_bit(S_SCAN_HW, &il->status))
                        break;
                msleep(20);
        }

        return test_bit(S_SCAN_HW, &il->status);
}
EXPORT_SYMBOL(il_scan_cancel_timeout);

/* Service response to C_SCAN (0x80) */
static void
il_hdl_scan(struct il_priv *il, struct il_rx_buf *rxb)
{
#ifdef CONFIG_IWLEGACY_DEBUG
        struct il_rx_pkt *pkt = rxb_addr(rxb);
        struct il_scanreq_notification *notif =
            (struct il_scanreq_notification *)pkt->u.raw;

        D_SCAN("Scan request status = 0x%x\n", notif->status);
#endif
}

/* Service N_SCAN_START (0x82) */
static void
il_hdl_scan_start(struct il_priv *il, struct il_rx_buf *rxb)
{
        struct il_rx_pkt *pkt = rxb_addr(rxb);
        struct il_scanstart_notification *notif =
            (struct il_scanstart_notification *)pkt->u.raw;
        il->scan_start_tsf = le32_to_cpu(notif->tsf_low);
        D_SCAN("Scan start: " "%d [802.11%s] "
               "(TSF: 0x%08X:%08X) - %d (beacon timer %u)\n", notif->channel,
               notif->band ? "bg" : "a", le32_to_cpu(notif->tsf_high),
               le32_to_cpu(notif->tsf_low), notif->status, notif->beacon_timer);
}

/* Service N_SCAN_RESULTS (0x83) */
static void
il_hdl_scan_results(struct il_priv *il, struct il_rx_buf *rxb)
{
#ifdef CONFIG_IWLEGACY_DEBUG
        struct il_rx_pkt *pkt = rxb_addr(rxb);
        struct il_scanresults_notification *notif =
            (struct il_scanresults_notification *)pkt->u.raw;

        D_SCAN("Scan ch.res: " "%d [802.11%s] " "(TSF: 0x%08X:%08X) - %d "
               "elapsed=%lu usec\n", notif->channel, notif->band ? "bg" : "a",
               le32_to_cpu(notif->tsf_high), le32_to_cpu(notif->tsf_low),
               le32_to_cpu(notif->stats[0]),
               le32_to_cpu(notif->tsf_low) - il->scan_start_tsf);
#endif
}

/* Service N_SCAN_COMPLETE (0x84) */
static void
il_hdl_scan_complete(struct il_priv *il, struct il_rx_buf *rxb)
{

#ifdef CONFIG_IWLEGACY_DEBUG
        struct il_rx_pkt *pkt = rxb_addr(rxb);
        struct il_scancomplete_notification *scan_notif = (void *)pkt->u.raw;
#endif

        D_SCAN("Scan complete: %d channels (TSF 0x%08X:%08X) - %d\n",
               scan_notif->scanned_channels, scan_notif->tsf_low,
               scan_notif->tsf_high, scan_notif->status);

        /* The HW is no longer scanning */
        clear_bit(S_SCAN_HW, &il->status);

        D_SCAN("Scan on %sGHz took %dms\n",
               (il->scan_band == NL80211_BAND_2GHZ) ? "2.4" : "5.2",
               jiffies_to_msecs(jiffies - il->scan_start));

        queue_work(il->workqueue, &il->scan_completed);
}

void
il_setup_rx_scan_handlers(struct il_priv *il)
{
        /* scan handlers */
        il->handlers[C_SCAN] = il_hdl_scan;
        il->handlers[N_SCAN_START] = il_hdl_scan_start;
        il->handlers[N_SCAN_RESULTS] = il_hdl_scan_results;
        il->handlers[N_SCAN_COMPLETE] = il_hdl_scan_complete;
}
EXPORT_SYMBOL(il_setup_rx_scan_handlers);

u16
il_get_active_dwell_time(struct il_priv *il, enum nl80211_band band,
                         u8 n_probes)
{
        if (band == NL80211_BAND_5GHZ)
                return IL_ACTIVE_DWELL_TIME_52 +
                    IL_ACTIVE_DWELL_FACTOR_52GHZ * (n_probes + 1);
        else
                return IL_ACTIVE_DWELL_TIME_24 +
                    IL_ACTIVE_DWELL_FACTOR_24GHZ * (n_probes + 1);
}
EXPORT_SYMBOL(il_get_active_dwell_time);

u16
il_get_passive_dwell_time(struct il_priv *il, enum nl80211_band band,
                          struct ieee80211_vif *vif)
{
        u16 value;

        u16 passive =
            (band ==
             NL80211_BAND_2GHZ) ? IL_PASSIVE_DWELL_BASE +
            IL_PASSIVE_DWELL_TIME_24 : IL_PASSIVE_DWELL_BASE +
            IL_PASSIVE_DWELL_TIME_52;

        if (il_is_any_associated(il)) {
                /*
                 * If we're associated, we clamp the maximum passive
                 * dwell time to be 98% of the smallest beacon interval
                 * (minus 2 * channel tune time)
                 */
                value = il->vif ? il->vif->bss_conf.beacon_int : 0;
                if (value > IL_PASSIVE_DWELL_BASE || !value)
                        value = IL_PASSIVE_DWELL_BASE;
                value = (value * 98) / 100 - IL_CHANNEL_TUNE_TIME * 2;
                passive = min(value, passive);
        }

        return passive;
}
EXPORT_SYMBOL(il_get_passive_dwell_time);

void
il_init_scan_params(struct il_priv *il)
{
        u8 ant_idx = fls(il->hw_params.valid_tx_ant) - 1;
        if (!il->scan_tx_ant[NL80211_BAND_5GHZ])
                il->scan_tx_ant[NL80211_BAND_5GHZ] = ant_idx;
        if (!il->scan_tx_ant[NL80211_BAND_2GHZ])
                il->scan_tx_ant[NL80211_BAND_2GHZ] = ant_idx;
}
EXPORT_SYMBOL(il_init_scan_params);

static int
il_scan_initiate(struct il_priv *il, struct ieee80211_vif *vif)
{
        int ret;

        lockdep_assert_held(&il->mutex);

        cancel_delayed_work(&il->scan_check);

        if (!il_is_ready_rf(il)) {
                IL_WARN("Request scan called when driver not ready.\n");
                return -EIO;
        }

        if (test_bit(S_SCAN_HW, &il->status)) {
                D_SCAN("Multiple concurrent scan requests in parallel.\n");
                return -EBUSY;
        }

        if (test_bit(S_SCAN_ABORTING, &il->status)) {
                D_SCAN("Scan request while abort pending.\n");
                return -EBUSY;
        }

        D_SCAN("Starting scan...\n");

        set_bit(S_SCANNING, &il->status);
        il->scan_start = jiffies;

        ret = il->ops->request_scan(il, vif);
        if (ret) {
                clear_bit(S_SCANNING, &il->status);
                return ret;
        }

        queue_delayed_work(il->workqueue, &il->scan_check,
                           IL_SCAN_CHECK_WATCHDOG);

        return 0;
}

int
il_mac_hw_scan(struct ieee80211_hw *hw, struct ieee80211_vif *vif,
               struct ieee80211_scan_request *hw_req)
{
        struct cfg80211_scan_request *req = &hw_req->req;
        struct il_priv *il = hw->priv;
        int ret;

        if (req->n_channels == 0) {
                IL_ERR("Can not scan on no channels.\n");
                return -EINVAL;
        }

        mutex_lock(&il->mutex);
        D_MAC80211("enter\n");

        if (test_bit(S_SCANNING, &il->status)) {
                D_SCAN("Scan already in progress.\n");
                ret = -EAGAIN;
                goto out_unlock;
        }

        /* mac80211 will only ask for one band at a time */
        il->scan_request = req;
        il->scan_vif = vif;
        il->scan_band = req->channels[0]->band;

        ret = il_scan_initiate(il, vif);

out_unlock:
        D_MAC80211("leave ret %d\n", ret);
        mutex_unlock(&il->mutex);

        return ret;
}
EXPORT_SYMBOL(il_mac_hw_scan);

static void
il_bg_scan_check(struct work_struct *data)
{
        struct il_priv *il =
            container_of(data, struct il_priv, scan_check.work);

        D_SCAN("Scan check work\n");

        /* Since we are here firmware does not finish scan and
         * most likely is in bad shape, so we don't bother to
         * send abort command, just force scan complete to mac80211 */
        mutex_lock(&il->mutex);
        il_force_scan_end(il);
        mutex_unlock(&il->mutex);
}

/**
 * il_fill_probe_req - fill in all required fields and IE for probe request
 */

u16
il_fill_probe_req(struct il_priv *il, struct ieee80211_mgmt *frame,
                  const u8 *ta, const u8 *ies, int ie_len, int left)
{
        int len = 0;
        u8 *pos = NULL;

        /* Make sure there is enough space for the probe request,
         * two mandatory IEs and the data */
        left -= 24;
        if (left < 0)
                return 0;

        frame->frame_control = cpu_to_le16(IEEE80211_STYPE_PROBE_REQ);
        eth_broadcast_addr(frame->da);
        memcpy(frame->sa, ta, ETH_ALEN);
        eth_broadcast_addr(frame->bssid);
        frame->seq_ctrl = 0;

        len += 24;

        /* ...next IE... */
        pos = &frame->u.probe_req.variable[0];

        /* fill in our indirect SSID IE */
        left -= 2;
        if (left < 0)
                return 0;
        *pos++ = WLAN_EID_SSID;
        *pos++ = 0;

        len += 2;

        if (WARN_ON(left < ie_len))
                return len;

        if (ies && ie_len) {
                memcpy(pos, ies, ie_len);
                len += ie_len;
        }

        return (u16) len;
}
EXPORT_SYMBOL(il_fill_probe_req);

static void
il_bg_abort_scan(struct work_struct *work)
{
        struct il_priv *il = container_of(work, struct il_priv, abort_scan);

        D_SCAN("Abort scan work\n");

        /* We keep scan_check work queued in case when firmware will not
         * report back scan completed notification */
        mutex_lock(&il->mutex);
        il_scan_cancel_timeout(il, 200);
        mutex_unlock(&il->mutex);
}

static void
il_bg_scan_completed(struct work_struct *work)
{
        struct il_priv *il = container_of(work, struct il_priv, scan_completed);
        bool aborted;

        D_SCAN("Completed scan.\n");

        cancel_delayed_work(&il->scan_check);

        mutex_lock(&il->mutex);

        aborted = test_and_clear_bit(S_SCAN_ABORTING, &il->status);
        if (aborted)
                D_SCAN("Aborted scan completed.\n");

        if (!test_and_clear_bit(S_SCANNING, &il->status)) {
                D_SCAN("Scan already completed.\n");
                goto out_settings;
        }

        il_complete_scan(il, aborted);

out_settings:
        /* Can we still talk to firmware ? */
        if (!il_is_ready_rf(il))
                goto out;

        /*
         * We do not commit power settings while scan is pending,
         * do it now if the settings changed.
         */
        il_power_set_mode(il, &il->power_data.sleep_cmd_next, false);
        il_set_tx_power(il, il->tx_power_next, false);

        il->ops->post_scan(il);

out:
        mutex_unlock(&il->mutex);
}

void
il_setup_scan_deferred_work(struct il_priv *il)
{
        INIT_WORK(&il->scan_completed, il_bg_scan_completed);
        INIT_WORK(&il->abort_scan, il_bg_abort_scan);
        INIT_DELAYED_WORK(&il->scan_check, il_bg_scan_check);
}
EXPORT_SYMBOL(il_setup_scan_deferred_work);

void
il_cancel_scan_deferred_work(struct il_priv *il)
{
        cancel_work_sync(&il->abort_scan);
        cancel_work_sync(&il->scan_completed);

        if (cancel_delayed_work_sync(&il->scan_check)) {
                mutex_lock(&il->mutex);
                il_force_scan_end(il);
                mutex_unlock(&il->mutex);
        }
}
EXPORT_SYMBOL(il_cancel_scan_deferred_work);

/* il->sta_lock must be held */
static void
il_sta_ucode_activate(struct il_priv *il, u8 sta_id)
{

        if (!(il->stations[sta_id].used & IL_STA_DRIVER_ACTIVE))
                IL_ERR("ACTIVATE a non DRIVER active station id %u addr %pM\n",
                       sta_id, il->stations[sta_id].sta.sta.addr);

        if (il->stations[sta_id].used & IL_STA_UCODE_ACTIVE) {
                D_ASSOC("STA id %u addr %pM already present"
                        " in uCode (according to driver)\n", sta_id,
                        il->stations[sta_id].sta.sta.addr);
        } else {
                il->stations[sta_id].used |= IL_STA_UCODE_ACTIVE;
                D_ASSOC("Added STA id %u addr %pM to uCode\n", sta_id,
                        il->stations[sta_id].sta.sta.addr);
        }
}

static int
il_process_add_sta_resp(struct il_priv *il, struct il_addsta_cmd *addsta,
                        struct il_rx_pkt *pkt, bool sync)
{
        u8 sta_id = addsta->sta.sta_id;
        unsigned long flags;
        int ret = -EIO;

        if (pkt->hdr.flags & IL_CMD_FAILED_MSK) {
                IL_ERR("Bad return from C_ADD_STA (0x%08X)\n", pkt->hdr.flags);
                return ret;
        }

        D_INFO("Processing response for adding station %u\n", sta_id);

        spin_lock_irqsave(&il->sta_lock, flags);

        switch (pkt->u.add_sta.status) {
        case ADD_STA_SUCCESS_MSK:
                D_INFO("C_ADD_STA PASSED\n");
                il_sta_ucode_activate(il, sta_id);
                ret = 0;
                break;
        case ADD_STA_NO_ROOM_IN_TBL:
                IL_ERR("Adding station %d failed, no room in table.\n", sta_id);
                break;
        case ADD_STA_NO_BLOCK_ACK_RESOURCE:
                IL_ERR("Adding station %d failed, no block ack resource.\n",
                       sta_id);
                break;
        case ADD_STA_MODIFY_NON_EXIST_STA:
                IL_ERR("Attempting to modify non-existing station %d\n",
                       sta_id);
                break;
        default:
                D_ASSOC("Received C_ADD_STA:(0x%08X)\n", pkt->u.add_sta.status);
                break;
        }

        D_INFO("%s station id %u addr %pM\n",
               il->stations[sta_id].sta.mode ==
               STA_CONTROL_MODIFY_MSK ? "Modified" : "Added", sta_id,
               il->stations[sta_id].sta.sta.addr);

        /*
         * XXX: The MAC address in the command buffer is often changed from
         * the original sent to the device. That is, the MAC address
         * written to the command buffer often is not the same MAC address
         * read from the command buffer when the command returns. This
         * issue has not yet been resolved and this debugging is left to
         * observe the problem.
         */
        D_INFO("%s station according to cmd buffer %pM\n",
               il->stations[sta_id].sta.mode ==
               STA_CONTROL_MODIFY_MSK ? "Modified" : "Added", addsta->sta.addr);
        spin_unlock_irqrestore(&il->sta_lock, flags);

        return ret;
}

static void
il_add_sta_callback(struct il_priv *il, struct il_device_cmd *cmd,
                    struct il_rx_pkt *pkt)
{
        struct il_addsta_cmd *addsta = (struct il_addsta_cmd *)cmd->cmd.payload;

        il_process_add_sta_resp(il, addsta, pkt, false);

}

int
il_send_add_sta(struct il_priv *il, struct il_addsta_cmd *sta, u8 flags)
{
        struct il_rx_pkt *pkt = NULL;
        int ret = 0;
        u8 data[sizeof(*sta)];
        struct il_host_cmd cmd = {
                .id = C_ADD_STA,
                .flags = flags,
                .data = data,
        };
        u8 sta_id __maybe_unused = sta->sta.sta_id;

        D_INFO("Adding sta %u (%pM) %ssynchronously\n", sta_id, sta->sta.addr,
               flags & CMD_ASYNC ? "a" : "");

        if (flags & CMD_ASYNC)
                cmd.callback = il_add_sta_callback;
        else {
                cmd.flags |= CMD_WANT_SKB;
                might_sleep();
        }

        cmd.len = il->ops->build_addsta_hcmd(sta, data);
        ret = il_send_cmd(il, &cmd);
        if (ret)
                return ret;
        if (flags & CMD_ASYNC)
                return 0;

        pkt = (struct il_rx_pkt *)cmd.reply_page;
        ret = il_process_add_sta_resp(il, sta, pkt, true);

        il_free_pages(il, cmd.reply_page);

        return ret;
}
EXPORT_SYMBOL(il_send_add_sta);

static void
il_set_ht_add_station(struct il_priv *il, u8 idx, struct ieee80211_sta *sta)
{
        struct ieee80211_sta_ht_cap *sta_ht_inf = &sta->ht_cap;
        __le32 sta_flags;

        if (!sta || !sta_ht_inf->ht_supported)
                goto done;

        D_ASSOC("spatial multiplexing power save mode: %s\n",
                (sta->smps_mode == IEEE80211_SMPS_STATIC) ? "static" :
                (sta->smps_mode == IEEE80211_SMPS_DYNAMIC) ? "dynamic" :
                "disabled");

        sta_flags = il->stations[idx].sta.station_flags;

        sta_flags &= ~(STA_FLG_RTS_MIMO_PROT_MSK | STA_FLG_MIMO_DIS_MSK);

        switch (sta->smps_mode) {
        case IEEE80211_SMPS_STATIC:
                sta_flags |= STA_FLG_MIMO_DIS_MSK;
                break;
        case IEEE80211_SMPS_DYNAMIC:
                sta_flags |= STA_FLG_RTS_MIMO_PROT_MSK;
                break;
        case IEEE80211_SMPS_OFF:
                break;
        default:
                IL_WARN("Invalid MIMO PS mode %d\n", sta->smps_mode);
                break;
        }

        sta_flags |=
            cpu_to_le32((u32) sta_ht_inf->
                        ampdu_factor << STA_FLG_MAX_AGG_SIZE_POS);

        sta_flags |=
            cpu_to_le32((u32) sta_ht_inf->
                        ampdu_density << STA_FLG_AGG_MPDU_DENSITY_POS);

        if (il_is_ht40_tx_allowed(il, &sta->ht_cap))
                sta_flags |= STA_FLG_HT40_EN_MSK;
        else
                sta_flags &= ~STA_FLG_HT40_EN_MSK;

        il->stations[idx].sta.station_flags = sta_flags;
done:
        return;
}

/**
 * il_prep_station - Prepare station information for addition
 *
 * should be called with sta_lock held
 */
u8
il_prep_station(struct il_priv *il, const u8 *addr, bool is_ap,
                struct ieee80211_sta *sta)
{
        struct il_station_entry *station;
        int i;
        u8 sta_id = IL_INVALID_STATION;
        u16 rate;

        if (is_ap)
                sta_id = IL_AP_ID;
        else if (is_broadcast_ether_addr(addr))
                sta_id = il->hw_params.bcast_id;
        else
                for (i = IL_STA_ID; i < il->hw_params.max_stations; i++) {
                        if (ether_addr_equal(il->stations[i].sta.sta.addr,
                                             addr)) {
                                sta_id = i;
                                break;
                        }

                        if (!il->stations[i].used &&
                            sta_id == IL_INVALID_STATION)
                                sta_id = i;
                }

        /*
         * These two conditions have the same outcome, but keep them
         * separate
         */
        if (unlikely(sta_id == IL_INVALID_STATION))
                return sta_id;

        /*
         * uCode is not able to deal with multiple requests to add a
         * station. Keep track if one is in progress so that we do not send
         * another.
         */
        if (il->stations[sta_id].used & IL_STA_UCODE_INPROGRESS) {
                D_INFO("STA %d already in process of being added.\n", sta_id);
                return sta_id;
        }

        if ((il->stations[sta_id].used & IL_STA_DRIVER_ACTIVE) &&
            (il->stations[sta_id].used & IL_STA_UCODE_ACTIVE) &&
            ether_addr_equal(il->stations[sta_id].sta.sta.addr, addr)) {
                D_ASSOC("STA %d (%pM) already added, not adding again.\n",
                        sta_id, addr);
                return sta_id;
        }

        station = &il->stations[sta_id];
        station->used = IL_STA_DRIVER_ACTIVE;
        D_ASSOC("Add STA to driver ID %d: %pM\n", sta_id, addr);
        il->num_stations++;

        /* Set up the C_ADD_STA command to send to device */
        memset(&station->sta, 0, sizeof(struct il_addsta_cmd));
        memcpy(station->sta.sta.addr, addr, ETH_ALEN);
        station->sta.mode = 0;
        station->sta.sta.sta_id = sta_id;
        station->sta.station_flags = 0;

        /*
         * OK to call unconditionally, since local stations (IBSS BSSID
         * STA and broadcast STA) pass in a NULL sta, and mac80211
         * doesn't allow HT IBSS.
         */
        il_set_ht_add_station(il, sta_id, sta);

        /* 3945 only */
        rate = (il->band == NL80211_BAND_5GHZ) ? RATE_6M_PLCP : RATE_1M_PLCP;
        /* Turn on both antennas for the station... */
        station->sta.rate_n_flags = cpu_to_le16(rate | RATE_MCS_ANT_AB_MSK);

        return sta_id;

}
EXPORT_SYMBOL_GPL(il_prep_station);

#define STA_WAIT_TIMEOUT (HZ/2)

/**
 * il_add_station_common -
 */
int
il_add_station_common(struct il_priv *il, const u8 *addr, bool is_ap,
                      struct ieee80211_sta *sta, u8 *sta_id_r)
{
        unsigned long flags_spin;
        int ret = 0;
        u8 sta_id;
        struct il_addsta_cmd sta_cmd;

        *sta_id_r = 0;
        spin_lock_irqsave(&il->sta_lock, flags_spin);
        sta_id = il_prep_station(il, addr, is_ap, sta);
        if (sta_id == IL_INVALID_STATION) {
                IL_ERR("Unable to prepare station %pM for addition\n", addr);
                spin_unlock_irqrestore(&il->sta_lock, flags_spin);
                return -EINVAL;
        }

        /*
         * uCode is not able to deal with multiple requests to add a
         * station. Keep track if one is in progress so that we do not send
         * another.
         */
        if (il->stations[sta_id].used & IL_STA_UCODE_INPROGRESS) {
                D_INFO("STA %d already in process of being added.\n", sta_id);
                spin_unlock_irqrestore(&il->sta_lock, flags_spin);
                return -EEXIST;
        }

        if ((il->stations[sta_id].used & IL_STA_DRIVER_ACTIVE) &&
            (il->stations[sta_id].used & IL_STA_UCODE_ACTIVE)) {
                D_ASSOC("STA %d (%pM) already added, not adding again.\n",
                        sta_id, addr);
                spin_unlock_irqrestore(&il->sta_lock, flags_spin);
                return -EEXIST;
        }

        il->stations[sta_id].used |= IL_STA_UCODE_INPROGRESS;
        memcpy(&sta_cmd, &il->stations[sta_id].sta,
               sizeof(struct il_addsta_cmd));
        spin_unlock_irqrestore(&il->sta_lock, flags_spin);

        /* Add station to device's station table */
        ret = il_send_add_sta(il, &sta_cmd, CMD_SYNC);
        if (ret) {
                spin_lock_irqsave(&il->sta_lock, flags_spin);
                IL_ERR("Adding station %pM failed.\n",
                       il->stations[sta_id].sta.sta.addr);
                il->stations[sta_id].used &= ~IL_STA_DRIVER_ACTIVE;
                il->stations[sta_id].used &= ~IL_STA_UCODE_INPROGRESS;
                spin_unlock_irqrestore(&il->sta_lock, flags_spin);
        }
        *sta_id_r = sta_id;
        return ret;
}
EXPORT_SYMBOL(il_add_station_common);

/**
 * il_sta_ucode_deactivate - deactivate ucode status for a station
 *
 * il->sta_lock must be held
 */
static void
il_sta_ucode_deactivate(struct il_priv *il, u8 sta_id)
{
        /* Ucode must be active and driver must be non active */
        if ((il->stations[sta_id].
             used & (IL_STA_UCODE_ACTIVE | IL_STA_DRIVER_ACTIVE)) !=
            IL_STA_UCODE_ACTIVE)
                IL_ERR("removed non active STA %u\n", sta_id);

        il->stations[sta_id].used &= ~IL_STA_UCODE_ACTIVE;

        memset(&il->stations[sta_id], 0, sizeof(struct il_station_entry));
        D_ASSOC("Removed STA %u\n", sta_id);
}

static int
il_send_remove_station(struct il_priv *il, const u8 * addr, int sta_id,
                       bool temporary)
{
        struct il_rx_pkt *pkt;
        int ret;

        unsigned long flags_spin;
        struct il_rem_sta_cmd rm_sta_cmd;

        struct il_host_cmd cmd = {
                .id = C_REM_STA,
                .len = sizeof(struct il_rem_sta_cmd),
                .flags = CMD_SYNC,
                .data = &rm_sta_cmd,
        };

        memset(&rm_sta_cmd, 0, sizeof(rm_sta_cmd));
        rm_sta_cmd.num_sta = 1;
        memcpy(&rm_sta_cmd.addr, addr, ETH_ALEN);

        cmd.flags |= CMD_WANT_SKB;

        ret = il_send_cmd(il, &cmd);

        if (ret)
                return ret;

        pkt = (struct il_rx_pkt *)cmd.reply_page;
        if (pkt->hdr.flags & IL_CMD_FAILED_MSK) {
                IL_ERR("Bad return from C_REM_STA (0x%08X)\n", pkt->hdr.flags);
                ret = -EIO;
        }

        if (!ret) {
                switch (pkt->u.rem_sta.status) {
                case REM_STA_SUCCESS_MSK:
                        if (!temporary) {
                                spin_lock_irqsave(&il->sta_lock, flags_spin);
                                il_sta_ucode_deactivate(il, sta_id);
                                spin_unlock_irqrestore(&il->sta_lock,
                                                       flags_spin);
                        }
                        D_ASSOC("C_REM_STA PASSED\n");
                        break;
                default:
                        ret = -EIO;
                        IL_ERR("C_REM_STA failed\n");
                        break;
                }
        }
        il_free_pages(il, cmd.reply_page);

        return ret;
}

/**
 * il_remove_station - Remove driver's knowledge of station.
 */
int
il_remove_station(struct il_priv *il, const u8 sta_id, const u8 * addr)
{
        unsigned long flags;

        if (!il_is_ready(il)) {
                D_INFO("Unable to remove station %pM, device not ready.\n",
                       addr);
                /*
                 * It is typical for stations to be removed when we are
                 * going down. Return success since device will be down
                 * soon anyway
                 */
                return 0;
        }

        D_ASSOC("Removing STA from driver:%d  %pM\n", sta_id, addr);

        if (WARN_ON(sta_id == IL_INVALID_STATION))
                return -EINVAL;

        spin_lock_irqsave(&il->sta_lock, flags);

        if (!(il->stations[sta_id].used & IL_STA_DRIVER_ACTIVE)) {
                D_INFO("Removing %pM but non DRIVER active\n", addr);
                goto out_err;
        }

        if (!(il->stations[sta_id].used & IL_STA_UCODE_ACTIVE)) {
                D_INFO("Removing %pM but non UCODE active\n", addr);
                goto out_err;
        }

        if (il->stations[sta_id].used & IL_STA_LOCAL) {
                kfree(il->stations[sta_id].lq);
                il->stations[sta_id].lq = NULL;
        }

        il->stations[sta_id].used &= ~IL_STA_DRIVER_ACTIVE;

        il->num_stations--;

        BUG_ON(il->num_stations < 0);

        spin_unlock_irqrestore(&il->sta_lock, flags);

        return il_send_remove_station(il, addr, sta_id, false);
out_err:
        spin_unlock_irqrestore(&il->sta_lock, flags);
        return -EINVAL;
}
EXPORT_SYMBOL_GPL(il_remove_station);

/**
 * il_clear_ucode_stations - clear ucode station table bits
 *
 * This function clears all the bits in the driver indicating
 * which stations are active in the ucode. Call when something
 * other than explicit station management would cause this in
 * the ucode, e.g. unassociated RXON.
 */
void
il_clear_ucode_stations(struct il_priv *il)
{
        int i;
        unsigned long flags_spin;
        bool cleared = false;

        D_INFO("Clearing ucode stations in driver\n");

        spin_lock_irqsave(&il->sta_lock, flags_spin);
        for (i = 0; i < il->hw_params.max_stations; i++) {
                if (il->stations[i].used & IL_STA_UCODE_ACTIVE) {
                        D_INFO("Clearing ucode active for station %d\n", i);
                        il->stations[i].used &= ~IL_STA_UCODE_ACTIVE;
                        cleared = true;
                }
        }
        spin_unlock_irqrestore(&il->sta_lock, flags_spin);

        if (!cleared)
                D_INFO("No active stations found to be cleared\n");
}
EXPORT_SYMBOL(il_clear_ucode_stations);

/**
 * il_restore_stations() - Restore driver known stations to device
 *
 * All stations considered active by driver, but not present in ucode, is
 * restored.
 *
 * Function sleeps.
 */
void
il_restore_stations(struct il_priv *il)
{
        struct il_addsta_cmd sta_cmd;
        struct il_link_quality_cmd lq;
        unsigned long flags_spin;
        int i;
        bool found = false;
        int ret;
        bool send_lq;

        if (!il_is_ready(il)) {
                D_INFO("Not ready yet, not restoring any stations.\n");
                return;
        }

        D_ASSOC("Restoring all known stations ... start.\n");
        spin_lock_irqsave(&il->sta_lock, flags_spin);
        for (i = 0; i < il->hw_params.max_stations; i++) {
                if ((il->stations[i].used & IL_STA_DRIVER_ACTIVE) &&
                    !(il->stations[i].used & IL_STA_UCODE_ACTIVE)) {
                        D_ASSOC("Restoring sta %pM\n",
                                il->stations[i].sta.sta.addr);
                        il->stations[i].sta.mode = 0;
                        il->stations[i].used |= IL_STA_UCODE_INPROGRESS;
                        found = true;
                }
        }

        for (i = 0; i < il->hw_params.max_stations; i++) {
                if ((il->stations[i].used & IL_STA_UCODE_INPROGRESS)) {
                        memcpy(&sta_cmd, &il->stations[i].sta,
                               sizeof(struct il_addsta_cmd));
                        send_lq = false;
                        if (il->stations[i].lq) {
                                memcpy(&lq, il->stations[i].lq,
                                       sizeof(struct il_link_quality_cmd));
                                send_lq = true;
                        }
                        spin_unlock_irqrestore(&il->sta_lock, flags_spin);
                        ret = il_send_add_sta(il, &sta_cmd, CMD_SYNC);
                        if (ret) {
                                spin_lock_irqsave(&il->sta_lock, flags_spin);
                                IL_ERR("Adding station %pM failed.\n",
                                       il->stations[i].sta.sta.addr);
                                il->stations[i].used &= ~IL_STA_DRIVER_ACTIVE;
                                il->stations[i].used &=
                                    ~IL_STA_UCODE_INPROGRESS;
                                spin_unlock_irqrestore(&il->sta_lock,
                                                       flags_spin);
                        }
                        /*
                         * Rate scaling has already been initialized, send
                         * current LQ command
                         */
                        if (send_lq)
                                il_send_lq_cmd(il, &lq, CMD_SYNC, true);
                        spin_lock_irqsave(&il->sta_lock, flags_spin);
                        il->stations[i].used &= ~IL_STA_UCODE_INPROGRESS;
                }
        }

        spin_unlock_irqrestore(&il->sta_lock, flags_spin);
        if (!found)
                D_INFO("Restoring all known stations"
                       " .... no stations to be restored.\n");
        else
                D_INFO("Restoring all known stations" " .... complete.\n");
}
EXPORT_SYMBOL(il_restore_stations);

int
il_get_free_ucode_key_idx(struct il_priv *il)
{
        int i;

        for (i = 0; i < il->sta_key_max_num; i++)
                if (!test_and_set_bit(i, &il->ucode_key_table))
                        return i;

        return WEP_INVALID_OFFSET;
}
EXPORT_SYMBOL(il_get_free_ucode_key_idx);

void
il_dealloc_bcast_stations(struct il_priv *il)
{
        unsigned long flags;
        int i;

        spin_lock_irqsave(&il->sta_lock, flags);
        for (i = 0; i < il->hw_params.max_stations; i++) {
                if (!(il->stations[i].used & IL_STA_BCAST))
                        continue;

                il->stations[i].used &= ~IL_STA_UCODE_ACTIVE;
                il->num_stations--;
                BUG_ON(il->num_stations < 0);
                kfree(il->stations[i].lq);
                il->stations[i].lq = NULL;
        }
        spin_unlock_irqrestore(&il->sta_lock, flags);
}
EXPORT_SYMBOL_GPL(il_dealloc_bcast_stations);

#ifdef CONFIG_IWLEGACY_DEBUG
static void
il_dump_lq_cmd(struct il_priv *il, struct il_link_quality_cmd *lq)
{
        int i;
        D_RATE("lq station id 0x%x\n", lq->sta_id);
        D_RATE("lq ant 0x%X 0x%X\n", lq->general_params.single_stream_ant_msk,
               lq->general_params.dual_stream_ant_msk);

        for (i = 0; i < LINK_QUAL_MAX_RETRY_NUM; i++)
                D_RATE("lq idx %d 0x%X\n", i, lq->rs_table[i].rate_n_flags);
}
#else
static inline void
il_dump_lq_cmd(struct il_priv *il, struct il_link_quality_cmd *lq)
{
}
#endif

/**
 * il_is_lq_table_valid() - Test one aspect of LQ cmd for validity
 *
 * It sometimes happens when a HT rate has been in use and we
 * loose connectivity with AP then mac80211 will first tell us that the
 * current channel is not HT anymore before removing the station. In such a
 * scenario the RXON flags will be updated to indicate we are not
 * communicating HT anymore, but the LQ command may still contain HT rates.
 * Test for this to prevent driver from sending LQ command between the time
 * RXON flags are updated and when LQ command is updated.
 */
static bool
il_is_lq_table_valid(struct il_priv *il, struct il_link_quality_cmd *lq)
{
        int i;

        if (il->ht.enabled)
                return true;

        D_INFO("Channel %u is not an HT channel\n", il->active.channel);
        for (i = 0; i < LINK_QUAL_MAX_RETRY_NUM; i++) {
                if (le32_to_cpu(lq->rs_table[i].rate_n_flags) & RATE_MCS_HT_MSK) {
                        D_INFO("idx %d of LQ expects HT channel\n", i);
                        return false;
                }
        }
        return true;
}

/**
 * il_send_lq_cmd() - Send link quality command
 * @init: This command is sent as part of station initialization right
 *        after station has been added.
 *
 * The link quality command is sent as the last step of station creation.
 * This is the special case in which init is set and we call a callback in
 * this case to clear the state indicating that station creation is in
 * progress.
 */
int
il_send_lq_cmd(struct il_priv *il, struct il_link_quality_cmd *lq,
               u8 flags, bool init)
{
        int ret = 0;
        unsigned long flags_spin;

        struct il_host_cmd cmd = {
                .id = C_TX_LINK_QUALITY_CMD,
                .len = sizeof(struct il_link_quality_cmd),
                .flags = flags,
                .data = lq,
        };

        if (WARN_ON(lq->sta_id == IL_INVALID_STATION))
                return -EINVAL;

        spin_lock_irqsave(&il->sta_lock, flags_spin);
        if (!(il->stations[lq->sta_id].used & IL_STA_DRIVER_ACTIVE)) {
                spin_unlock_irqrestore(&il->sta_lock, flags_spin);
                return -EINVAL;
        }
        spin_unlock_irqrestore(&il->sta_lock, flags_spin);

        il_dump_lq_cmd(il, lq);
        BUG_ON(init && (cmd.flags & CMD_ASYNC));

        if (il_is_lq_table_valid(il, lq))
                ret = il_send_cmd(il, &cmd);
        else
                ret = -EINVAL;

        if (cmd.flags & CMD_ASYNC)
                return ret;

        if (init) {
                D_INFO("init LQ command complete,"
                       " clearing sta addition status for sta %d\n",
                       lq->sta_id);
                spin_lock_irqsave(&il->sta_lock, flags_spin);
                il->stations[lq->sta_id].used &= ~IL_STA_UCODE_INPROGRESS;
                spin_unlock_irqrestore(&il->sta_lock, flags_spin);
        }
        return ret;
}
EXPORT_SYMBOL(il_send_lq_cmd);

int
il_mac_sta_remove(struct ieee80211_hw *hw, struct ieee80211_vif *vif,
                  struct ieee80211_sta *sta)
{
        struct il_priv *il = hw->priv;
        struct il_station_priv_common *sta_common = (void *)sta->drv_priv;
        int ret;

        mutex_lock(&il->mutex);
        D_MAC80211("enter station %pM\n", sta->addr);

        ret = il_remove_station(il, sta_common->sta_id, sta->addr);
        if (ret)
                IL_ERR("Error removing station %pM\n", sta->addr);

        D_MAC80211("leave ret %d\n", ret);
        mutex_unlock(&il->mutex);

        return ret;
}
EXPORT_SYMBOL(il_mac_sta_remove);

/************************** RX-FUNCTIONS ****************************/
/*
 * Rx theory of operation
 *
 * Driver allocates a circular buffer of Receive Buffer Descriptors (RBDs),
 * each of which point to Receive Buffers to be filled by the NIC.  These get
 * used not only for Rx frames, but for any command response or notification
 * from the NIC.  The driver and NIC manage the Rx buffers by means
 * of idxes into the circular buffer.
 *
 * Rx Queue Indexes
 * The host/firmware share two idx registers for managing the Rx buffers.
 *
 * The READ idx maps to the first position that the firmware may be writing
 * to -- the driver can read up to (but not including) this position and get
 * good data.
 * The READ idx is managed by the firmware once the card is enabled.
 *
 * The WRITE idx maps to the last position the driver has read from -- the
 * position preceding WRITE is the last slot the firmware can place a packet.
 *
 * The queue is empty (no good data) if WRITE = READ - 1, and is full if
 * WRITE = READ.
 *
 * During initialization, the host sets up the READ queue position to the first
 * IDX position, and WRITE to the last (READ - 1 wrapped)
 *
 * When the firmware places a packet in a buffer, it will advance the READ idx
 * and fire the RX interrupt.  The driver can then query the READ idx and
 * process as many packets as possible, moving the WRITE idx forward as it
 * resets the Rx queue buffers with new memory.
 *
 * The management in the driver is as follows:
 * + A list of pre-allocated SKBs is stored in iwl->rxq->rx_free.  When
 *   iwl->rxq->free_count drops to or below RX_LOW_WATERMARK, work is scheduled
 *   to replenish the iwl->rxq->rx_free.
 * + In il_rx_replenish (scheduled) if 'processed' != 'read' then the
 *   iwl->rxq is replenished and the READ IDX is updated (updating the
 *   'processed' and 'read' driver idxes as well)
 * + A received packet is processed and handed to the kernel network stack,
 *   detached from the iwl->rxq.  The driver 'processed' idx is updated.
 * + The Host/Firmware iwl->rxq is replenished at tasklet time from the rx_free
 *   list. If there are no allocated buffers in iwl->rxq->rx_free, the READ
 *   IDX is not incremented and iwl->status(RX_STALLED) is set.  If there
 *   were enough free buffers and RX_STALLED is set it is cleared.
 *
 *
 * Driver sequence:
 *
 * il_rx_queue_alloc()   Allocates rx_free
 * il_rx_replenish()     Replenishes rx_free list from rx_used, and calls
 *                            il_rx_queue_restock
 * il_rx_queue_restock() Moves available buffers from rx_free into Rx
 *                            queue, updates firmware pointers, and updates
 *                            the WRITE idx.  If insufficient rx_free buffers
 *                            are available, schedules il_rx_replenish
 *
 * -- enable interrupts --
 * ISR - il_rx()         Detach il_rx_bufs from pool up to the
 *                            READ IDX, detaching the SKB from the pool.
 *                            Moves the packet buffer from queue to rx_used.
 *                            Calls il_rx_queue_restock to refill any empty
 *                            slots.
 * ...
 *
 */

/**
 * il_rx_queue_space - Return number of free slots available in queue.
 */
int
il_rx_queue_space(const struct il_rx_queue *q)
{
        int s = q->read - q->write;
        if (s <= 0)
                s += RX_QUEUE_SIZE;
        /* keep some buffer to not confuse full and empty queue */
        s -= 2;
        if (s < 0)
                s = 0;
        return s;
}
EXPORT_SYMBOL(il_rx_queue_space);

/**
 * il_rx_queue_update_write_ptr - Update the write pointer for the RX queue
 */
void
il_rx_queue_update_write_ptr(struct il_priv *il, struct il_rx_queue *q)
{
        unsigned long flags;
        u32 rx_wrt_ptr_reg = il->hw_params.rx_wrt_ptr_reg;
        u32 reg;

        spin_lock_irqsave(&q->lock, flags);

        if (q->need_update == 0)
                goto exit_unlock;

        /* If power-saving is in use, make sure device is awake */
        if (test_bit(S_POWER_PMI, &il->status)) {
                reg = _il_rd(il, CSR_UCODE_DRV_GP1);

                if (reg & CSR_UCODE_DRV_GP1_BIT_MAC_SLEEP) {
                        D_INFO("Rx queue requesting wakeup," " GP1 = 0x%x\n",
                               reg);
                        il_set_bit(il, CSR_GP_CNTRL,
                                   CSR_GP_CNTRL_REG_FLAG_MAC_ACCESS_REQ);
                        goto exit_unlock;
                }

                q->write_actual = (q->write & ~0x7);
                il_wr(il, rx_wrt_ptr_reg, q->write_actual);

                /* Else device is assumed to be awake */
        } else {
                /* Device expects a multiple of 8 */
                q->write_actual = (q->write & ~0x7);
                il_wr(il, rx_wrt_ptr_reg, q->write_actual);
        }

        q->need_update = 0;

exit_unlock:
        spin_unlock_irqrestore(&q->lock, flags);
}
EXPORT_SYMBOL(il_rx_queue_update_write_ptr);

int
il_rx_queue_alloc(struct il_priv *il)
{
        struct il_rx_queue *rxq = &il->rxq;
        struct device *dev = &il->pci_dev->dev;
        int i;

        spin_lock_init(&rxq->lock);
        INIT_LIST_HEAD(&rxq->rx_free);
        INIT_LIST_HEAD(&rxq->rx_used);

        /* Alloc the circular buffer of Read Buffer Descriptors (RBDs) */
        rxq->bd = dma_alloc_coherent(dev, 4 * RX_QUEUE_SIZE, &rxq->bd_dma,
                                     GFP_KERNEL);
        if (!rxq->bd)
                goto err_bd;

        rxq->rb_stts = dma_alloc_coherent(dev, sizeof(struct il_rb_status),
                                          &rxq->rb_stts_dma, GFP_KERNEL);
        if (!rxq->rb_stts)
                goto err_rb;

        /* Fill the rx_used queue with _all_ of the Rx buffers */
        for (i = 0; i < RX_FREE_BUFFERS + RX_QUEUE_SIZE; i++)
                list_add_tail(&rxq->pool[i].list, &rxq->rx_used);

        /* Set us so that we have processed and used all buffers, but have
         * not restocked the Rx queue with fresh buffers */
        rxq->read = rxq->write = 0;
        rxq->write_actual = 0;
        rxq->free_count = 0;
        rxq->need_update = 0;
        return 0;

err_rb:
        dma_free_coherent(&il->pci_dev->dev, 4 * RX_QUEUE_SIZE, rxq->bd,
                          rxq->bd_dma);
err_bd:
        return -ENOMEM;
}
EXPORT_SYMBOL(il_rx_queue_alloc);

void
il_hdl_spectrum_measurement(struct il_priv *il, struct il_rx_buf *rxb)
{
        struct il_rx_pkt *pkt = rxb_addr(rxb);
        struct il_spectrum_notification *report = &(pkt->u.spectrum_notif);

        if (!report->state) {
                D_11H("Spectrum Measure Notification: Start\n");
                return;
        }

        memcpy(&il->measure_report, report, sizeof(*report));
        il->measurement_status |= MEASUREMENT_READY;
}
EXPORT_SYMBOL(il_hdl_spectrum_measurement);

/*
 * returns non-zero if packet should be dropped
 */
int
il_set_decrypted_flag(struct il_priv *il, struct ieee80211_hdr *hdr,
                      u32 decrypt_res, struct ieee80211_rx_status *stats)
{
        u16 fc = le16_to_cpu(hdr->frame_control);

        /*
         * All contexts have the same setting here due to it being
         * a module parameter, so OK to check any context.
         */
        if (il->active.filter_flags & RXON_FILTER_DIS_DECRYPT_MSK)
                return 0;

        if (!(fc & IEEE80211_FCTL_PROTECTED))
                return 0;

        D_RX("decrypt_res:0x%x\n", decrypt_res);
        switch (decrypt_res & RX_RES_STATUS_SEC_TYPE_MSK) {
        case RX_RES_STATUS_SEC_TYPE_TKIP:
                /* The uCode has got a bad phase 1 Key, pushes the packet.
                 * Decryption will be done in SW. */
                if ((decrypt_res & RX_RES_STATUS_DECRYPT_TYPE_MSK) ==
                    RX_RES_STATUS_BAD_KEY_TTAK)
                        break;
                /* fall through */

        case RX_RES_STATUS_SEC_TYPE_WEP:
                if ((decrypt_res & RX_RES_STATUS_DECRYPT_TYPE_MSK) ==
                    RX_RES_STATUS_BAD_ICV_MIC) {
                        /* bad ICV, the packet is destroyed since the
                         * decryption is inplace, drop it */
                        D_RX("Packet destroyed\n");
                        return -1;
                }
                /* fall through */
        case RX_RES_STATUS_SEC_TYPE_CCMP:
                if ((decrypt_res & RX_RES_STATUS_DECRYPT_TYPE_MSK) ==
                    RX_RES_STATUS_DECRYPT_OK) {
                        D_RX("hw decrypt successfully!!!\n");
                        stats->flag |= RX_FLAG_DECRYPTED;
                }
                break;

        default:
                break;
        }
        return 0;
}
EXPORT_SYMBOL(il_set_decrypted_flag);

/**
 * il_txq_update_write_ptr - Send new write idx to hardware
 */
void
il_txq_update_write_ptr(struct il_priv *il, struct il_tx_queue *txq)
{
        u32 reg = 0;
        int txq_id = txq->q.id;

        if (txq->need_update == 0)
                return;

        /* if we're trying to save power */
        if (test_bit(S_POWER_PMI, &il->status)) {
                /* wake up nic if it's powered down ...
                 * uCode will wake up, and interrupt us again, so next
                 * time we'll skip this part. */
                reg = _il_rd(il, CSR_UCODE_DRV_GP1);

                if (reg & CSR_UCODE_DRV_GP1_BIT_MAC_SLEEP) {
                        D_INFO("Tx queue %d requesting wakeup," " GP1 = 0x%x\n",
                               txq_id, reg);
                        il_set_bit(il, CSR_GP_CNTRL,
                                   CSR_GP_CNTRL_REG_FLAG_MAC_ACCESS_REQ);
                        return;
                }

                il_wr(il, HBUS_TARG_WRPTR, txq->q.write_ptr | (txq_id << 8));

                /*
                 * else not in power-save mode,
                 * uCode will never sleep when we're
                 * trying to tx (during RFKILL, we're not trying to tx).
                 */
        } else
                _il_wr(il, HBUS_TARG_WRPTR, txq->q.write_ptr | (txq_id << 8));
        txq->need_update = 0;
}
EXPORT_SYMBOL(il_txq_update_write_ptr);

/**
 * il_tx_queue_unmap -  Unmap any remaining DMA mappings and free skb's
 */
void
il_tx_queue_unmap(struct il_priv *il, int txq_id)
{
        struct il_tx_queue *txq = &il->txq[txq_id];
        struct il_queue *q = &txq->q;

        if (q->n_bd == 0)
                return;

        while (q->write_ptr != q->read_ptr) {
                il->ops->txq_free_tfd(il, txq);
                q->read_ptr = il_queue_inc_wrap(q->read_ptr, q->n_bd);
        }
}
EXPORT_SYMBOL(il_tx_queue_unmap);

/**
 * il_tx_queue_free - Deallocate DMA queue.
 * @txq: Transmit queue to deallocate.
 *
 * Empty queue by removing and destroying all BD's.
 * Free all buffers.
 * 0-fill, but do not free "txq" descriptor structure.
 */
void
il_tx_queue_free(struct il_priv *il, int txq_id)
{
        struct il_tx_queue *txq = &il->txq[txq_id];
        struct device *dev = &il->pci_dev->dev;
        int i;

        il_tx_queue_unmap(il, txq_id);

        /* De-alloc array of command/tx buffers */
        if (txq->cmd) {
                for (i = 0; i < TFD_TX_CMD_SLOTS; i++)
                        kfree(txq->cmd[i]);
        }

        /* De-alloc circular buffer of TFDs */
        if (txq->q.n_bd)
                dma_free_coherent(dev, il->hw_params.tfd_size * txq->q.n_bd,
                                  txq->tfds, txq->q.dma_addr);

        /* De-alloc array of per-TFD driver data */
        kfree(txq->skbs);
        txq->skbs = NULL;

        /* deallocate arrays */
        kfree(txq->cmd);
        kfree(txq->meta);
        txq->cmd = NULL;
        txq->meta = NULL;

        /* 0-fill queue descriptor structure */
        memset(txq, 0, sizeof(*txq));
}
EXPORT_SYMBOL(il_tx_queue_free);

/**
 * il_cmd_queue_unmap - Unmap any remaining DMA mappings from command queue
 */
void
il_cmd_queue_unmap(struct il_priv *il)
{
        struct il_tx_queue *txq = &il->txq[il->cmd_queue];
        struct il_queue *q = &txq->q;
        int i;

        if (q->n_bd == 0)
                return;

        while (q->read_ptr != q->write_ptr) {
                i = il_get_cmd_idx(q, q->read_ptr, 0);

                if (txq->meta[i].flags & CMD_MAPPED) {
                        pci_unmap_single(il->pci_dev,
                                         dma_unmap_addr(&txq->meta[i], mapping),
                                         dma_unmap_len(&txq->meta[i], len),
                                         PCI_DMA_BIDIRECTIONAL);
                        txq->meta[i].flags = 0;
                }

                q->read_ptr = il_queue_inc_wrap(q->read_ptr, q->n_bd);
        }

        i = q->n_win;
        if (txq->meta[i].flags & CMD_MAPPED) {
                pci_unmap_single(il->pci_dev,
                                 dma_unmap_addr(&txq->meta[i], mapping),
                                 dma_unmap_len(&txq->meta[i], len),
                                 PCI_DMA_BIDIRECTIONAL);
                txq->meta[i].flags = 0;
        }
}
EXPORT_SYMBOL(il_cmd_queue_unmap);

/**
 * il_cmd_queue_free - Deallocate DMA queue.
 * @txq: Transmit queue to deallocate.
 *
 * Empty queue by removing and destroying all BD's.
 * Free all buffers.
 * 0-fill, but do not free "txq" descriptor structure.
 */
void
il_cmd_queue_free(struct il_priv *il)
{
        struct il_tx_queue *txq = &il->txq[il->cmd_queue];
        struct device *dev = &il->pci_dev->dev;
        int i;

        il_cmd_queue_unmap(il);

        /* De-alloc array of command/tx buffers */
        if (txq->cmd) {
                for (i = 0; i <= TFD_CMD_SLOTS; i++)
                        kfree(txq->cmd[i]);
        }

        /* De-alloc circular buffer of TFDs */
        if (txq->q.n_bd)
                dma_free_coherent(dev, il->hw_params.tfd_size * txq->q.n_bd,
                                  txq->tfds, txq->q.dma_addr);

        /* deallocate arrays */
        kfree(txq->cmd);
        kfree(txq->meta);
        txq->cmd = NULL;
        txq->meta = NULL;

        /* 0-fill queue descriptor structure */
        memset(txq, 0, sizeof(*txq));
}
EXPORT_SYMBOL(il_cmd_queue_free);

/*************** DMA-QUEUE-GENERAL-FUNCTIONS  *****
 * DMA services
 *
 * Theory of operation
 *
 * A Tx or Rx queue resides in host DRAM, and is comprised of a circular buffer
 * of buffer descriptors, each of which points to one or more data buffers for
 * the device to read from or fill.  Driver and device exchange status of each
 * queue via "read" and "write" pointers.  Driver keeps minimum of 2 empty
 * entries in each circular buffer, to protect against confusing empty and full
 * queue states.
 *
 * The device reads or writes the data in the queues via the device's several
 * DMA/FIFO channels.  Each queue is mapped to a single DMA channel.
 *
 * For Tx queue, there are low mark and high mark limits. If, after queuing
 * the packet for Tx, free space become < low mark, Tx queue stopped. When
 * reclaiming packets (on 'tx done IRQ), if free space become > high mark,
 * Tx queue resumed.
 *
 * See more detailed info in 4965.h.
 ***************************************************/

int
il_queue_space(const struct il_queue *q)
{
        int s = q->read_ptr - q->write_ptr;

        if (q->read_ptr > q->write_ptr)
                s -= q->n_bd;

        if (s <= 0)
                s += q->n_win;
        /* keep some reserve to not confuse empty and full situations */
        s -= 2;
        if (s < 0)
                s = 0;
        return s;
}
EXPORT_SYMBOL(il_queue_space);


/**
 * il_queue_init - Initialize queue's high/low-water and read/write idxes
 */
static int
il_queue_init(struct il_priv *il, struct il_queue *q, int slots, u32 id)
{
        /*
         * TFD_QUEUE_SIZE_MAX must be power-of-two size, otherwise
         * il_queue_inc_wrap and il_queue_dec_wrap are broken.
         */
        BUILD_BUG_ON(TFD_QUEUE_SIZE_MAX & (TFD_QUEUE_SIZE_MAX - 1));
        /* FIXME: remove q->n_bd */
        q->n_bd = TFD_QUEUE_SIZE_MAX;

        q->n_win = slots;
        q->id = id;

        /* slots_must be power-of-two size, otherwise
         * il_get_cmd_idx is broken. */
        BUG_ON(!is_power_of_2(slots));

        q->low_mark = q->n_win / 4;
        if (q->low_mark < 4)
                q->low_mark = 4;

        q->high_mark = q->n_win / 8;
        if (q->high_mark < 2)
                q->high_mark = 2;

        q->write_ptr = q->read_ptr = 0;

        return 0;
}

/**
 * il_tx_queue_alloc - Alloc driver data and TFD CB for one Tx/cmd queue
 */
static int
il_tx_queue_alloc(struct il_priv *il, struct il_tx_queue *txq, u32 id)
{
        struct device *dev = &il->pci_dev->dev;
        size_t tfd_sz = il->hw_params.tfd_size * TFD_QUEUE_SIZE_MAX;

        /* Driver ilate data, only for Tx (not command) queues,
         * not shared with device. */
        if (id != il->cmd_queue) {
                txq->skbs = kcalloc(TFD_QUEUE_SIZE_MAX,
                                    sizeof(struct sk_buff *),
                                    GFP_KERNEL);
                if (!txq->skbs) {
                        IL_ERR("Fail to alloc skbs\n");
                        goto error;
                }
        } else
                txq->skbs = NULL;

        /* Circular buffer of transmit frame descriptors (TFDs),
         * shared with device */
        txq->tfds =
            dma_alloc_coherent(dev, tfd_sz, &txq->q.dma_addr, GFP_KERNEL);
        if (!txq->tfds)
                goto error;

        txq->q.id = id;

        return 0;

error:
        kfree(txq->skbs);
        txq->skbs = NULL;

        return -ENOMEM;
}