/*
 * Copyright (c) 2004-2007 Reyk Floeter <reyk@openbsd.org>
 * Copyright (c) 2006-2009 Nick Kossifidis <mickflemm@gmail.com>
 * Copyright (c) 2007-2008 Jiri Slaby <jirislaby@gmail.com>
 * Copyright (c) 2008-2009 Felix Fietkau <nbd@openwrt.org>
 *
 * Permission to use, copy, modify, and distribute this software for any
 * purpose with or without fee is hereby granted, provided that the above
 * copyright notice and this permission notice appear in all copies.
 *
 * THE SOFTWARE IS PROVIDED "AS IS" AND THE AUTHOR DISCLAIMS ALL WARRANTIES
 * WITH REGARD TO THIS SOFTWARE INCLUDING ALL IMPLIED WARRANTIES OF
 * MERCHANTABILITY AND FITNESS. IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR
 * ANY SPECIAL, DIRECT, INDIRECT, OR CONSEQUENTIAL DAMAGES OR ANY DAMAGES
 * WHATSOEVER RESULTING FROM LOSS OF USE, DATA OR PROFITS, WHETHER IN AN
 * ACTION OF CONTRACT, NEGLIGENCE OR OTHER TORTIOUS ACTION, ARISING OUT OF
 * OR IN CONNECTION WITH THE USE OR PERFORMANCE OF THIS SOFTWARE.
 *
 */

/***********************\
* PHY related functions *
\***********************/

#define pr_fmt(fmt) KBUILD_MODNAME ": " fmt

#include <linux/delay.h>
#include <linux/slab.h>
#include <asm/unaligned.h>

#include "ath5k.h"
#include "reg.h"
#include "rfbuffer.h"
#include "rfgain.h"
#include "../regd.h"


/**
 * DOC: PHY related functions
 *
 * Here we handle the low-level functions related to baseband
 * and analog frontend (RF) parts. This is by far the most complex
 * part of the hw code so make sure you know what you are doing.
 *
 * Here is a list of what this is all about:
 *
 * - Channel setting/switching
 *
 * - Automatic Gain Control (AGC) calibration
 *
 * - Noise Floor calibration
 *
 * - I/Q imbalance calibration (QAM correction)
 *
 * - Calibration due to thermal changes (gain_F)
 *
 * - Spur noise mitigation
 *
 * - RF/PHY initialization for the various operating modes and bwmodes
 *
 * - Antenna control
 *
 * - TX power control per channel/rate/packet type
 *
 * Also have in mind we never got documentation for most of these
 * functions, what we have comes mostly from Atheros's code, reverse
 * engineering and patent docs/presentations etc.
 */


/******************\
* Helper functions *
\******************/

/**
 * ath5k_hw_radio_revision() - Get the PHY Chip revision
 * @ah: The &struct ath5k_hw
 * @band: One of enum nl80211_band
 *
 * Returns the revision number of a 2GHz, 5GHz or single chip
 * radio.
 */
u16
ath5k_hw_radio_revision(struct ath5k_hw *ah, enum nl80211_band band)
{
        unsigned int i;
        u32 srev;
        u16 ret;

        /*
         * Set the radio chip access register
         */
        switch (band) {
        case NL80211_BAND_2GHZ:
                ath5k_hw_reg_write(ah, AR5K_PHY_SHIFT_2GHZ, AR5K_PHY(0));
                break;
        case NL80211_BAND_5GHZ:
                ath5k_hw_reg_write(ah, AR5K_PHY_SHIFT_5GHZ, AR5K_PHY(0));
                break;
        default:
                return 0;
        }

        usleep_range(2000, 2500);

        /* ...wait until PHY is ready and read the selected radio revision */
        ath5k_hw_reg_write(ah, 0x00001c16, AR5K_PHY(0x34));

        for (i = 0; i < 8; i++)
                ath5k_hw_reg_write(ah, 0x00010000, AR5K_PHY(0x20));

        if (ah->ah_version == AR5K_AR5210) {
                srev = (ath5k_hw_reg_read(ah, AR5K_PHY(256)) >> 28) & 0xf;
                ret = (u16)ath5k_hw_bitswap(srev, 4) + 1;
        } else {
                srev = (ath5k_hw_reg_read(ah, AR5K_PHY(0x100)) >> 24) & 0xff;
                ret = (u16)ath5k_hw_bitswap(((srev & 0xf0) >> 4) |
                                ((srev & 0x0f) << 4), 8);
        }

        /* Reset to the 5GHz mode */
        ath5k_hw_reg_write(ah, AR5K_PHY_SHIFT_5GHZ, AR5K_PHY(0));

        return ret;
}

/**
 * ath5k_channel_ok() - Check if a channel is supported by the hw
 * @ah: The &struct ath5k_hw
 * @channel: The &struct ieee80211_channel
 *
 * Note: We don't do any regulatory domain checks here, it's just
 * a sanity check.
 */
bool
ath5k_channel_ok(struct ath5k_hw *ah, struct ieee80211_channel *channel)
{
        u16 freq = channel->center_freq;

        /* Check if the channel is in our supported range */
        if (channel->band == NL80211_BAND_2GHZ) {
                if ((freq >= ah->ah_capabilities.cap_range.range_2ghz_min) &&
                    (freq <= ah->ah_capabilities.cap_range.range_2ghz_max))
                        return true;
        } else if (channel->band == NL80211_BAND_5GHZ)
                if ((freq >= ah->ah_capabilities.cap_range.range_5ghz_min) &&
                    (freq <= ah->ah_capabilities.cap_range.range_5ghz_max))
                        return true;

        return false;
}

/**
 * ath5k_hw_chan_has_spur_noise() - Check if channel is sensitive to spur noise
 * @ah: The &struct ath5k_hw
 * @channel: The &struct ieee80211_channel
 */
bool
ath5k_hw_chan_has_spur_noise(struct ath5k_hw *ah,
                                struct ieee80211_channel *channel)
{
        u8 refclk_freq;

        if ((ah->ah_radio == AR5K_RF5112) ||
        (ah->ah_radio == AR5K_RF5413) ||
        (ah->ah_radio == AR5K_RF2413) ||
        (ah->ah_mac_version == (AR5K_SREV_AR2417 >> 4)))
                refclk_freq = 40;
        else
                refclk_freq = 32;

        if ((channel->center_freq % refclk_freq != 0) &&
        ((channel->center_freq % refclk_freq < 10) ||
        (channel->center_freq % refclk_freq > 22)))
                return true;
        else
                return false;
}

/**
 * ath5k_hw_rfb_op() - Perform an operation on the given RF Buffer
 * @ah: The &struct ath5k_hw
 * @rf_regs: The struct ath5k_rf_reg
 * @val: New value
 * @reg_id: RF register ID
 * @set: Indicate we need to swap data
 *
 * This is an internal function used to modify RF Banks before
 * writing them to AR5K_RF_BUFFER. Check out rfbuffer.h for more
 * infos.
 */
static unsigned int
ath5k_hw_rfb_op(struct ath5k_hw *ah, const struct ath5k_rf_reg *rf_regs,
                                        u32 val, u8 reg_id, bool set)
{
        const struct ath5k_rf_reg *rfreg = NULL;
        u8 offset, bank, num_bits, col, position;
        u16 entry;
        u32 mask, data, last_bit, bits_shifted, first_bit;
        u32 *rfb;
        s32 bits_left;
        int i;

        data = 0;
        rfb = ah->ah_rf_banks;

        for (i = 0; i < ah->ah_rf_regs_count; i++) {
                if (rf_regs[i].index == reg_id) {
                        rfreg = &rf_regs[i];
                        break;
                }
        }

        if (rfb == NULL || rfreg == NULL) {
                ATH5K_PRINTF("Rf register not found!\n");
                /* should not happen */
                return 0;
        }

        bank = rfreg->bank;
        num_bits = rfreg->field.len;
        first_bit = rfreg->field.pos;
        col = rfreg->field.col;

        /* first_bit is an offset from bank's
         * start. Since we have all banks on
         * the same array, we use this offset
         * to mark each bank's start */
        offset = ah->ah_offset[bank];

        /* Boundary check */
        if (!(col <= 3 && num_bits <= 32 && first_bit + num_bits <= 319)) {
                ATH5K_PRINTF("invalid values at offset %u\n", offset);
                return 0;
        }

        entry = ((first_bit - 1) / 8) + offset;
        position = (first_bit - 1) % 8;

        if (set)
                data = ath5k_hw_bitswap(val, num_bits);

        for (bits_shifted = 0, bits_left = num_bits; bits_left > 0;
             position = 0, entry++) {

                last_bit = (position + bits_left > 8) ? 8 :
                                        position + bits_left;

                mask = (((1 << last_bit) - 1) ^ ((1 << position) - 1)) <<
                                                                (col * 8);

                if (set) {
                        rfb[entry] &= ~mask;
                        rfb[entry] |= ((data << position) << (col * 8)) & mask;
                        data >>= (8 - position);
                } else {
                        data |= (((rfb[entry] & mask) >> (col * 8)) >> position)
                                << bits_shifted;
                        bits_shifted += last_bit - position;
                }

                bits_left -= 8 - position;
        }

        data = set ? 1 : ath5k_hw_bitswap(data, num_bits);

        return data;
}

/**
 * ath5k_hw_write_ofdm_timings() - set OFDM timings on AR5212
 * @ah: the &struct ath5k_hw
 * @channel: the currently set channel upon reset
 *
 * Write the delta slope coefficient (used on pilot tracking ?) for OFDM
 * operation on the AR5212 upon reset. This is a helper for ath5k_hw_phy_init.
 *
 * Since delta slope is floating point we split it on its exponent and
 * mantissa and provide these values on hw.
 *
 * For more infos i think this patent is related
 * "http://www.freepatentsonline.com/7184495.html"
 */
static inline int
ath5k_hw_write_ofdm_timings(struct ath5k_hw *ah,
                                struct ieee80211_channel *channel)
{
        /* Get exponent and mantissa and set it */
        u32 coef_scaled, coef_exp, coef_man,
                ds_coef_exp, ds_coef_man, clock;

        BUG_ON(!(ah->ah_version == AR5K_AR5212) ||
                (channel->hw_value == AR5K_MODE_11B));

        /* Get coefficient
         * ALGO: coef = (5 * clock / carrier_freq) / 2
         * we scale coef by shifting clock value by 24 for
         * better precision since we use integers */
        switch (ah->ah_bwmode) {
        case AR5K_BWMODE_40MHZ:
                clock = 40 * 2;
                break;
        case AR5K_BWMODE_10MHZ:
                clock = 40 / 2;
                break;
        case AR5K_BWMODE_5MHZ:
                clock = 40 / 4;
                break;
        default:
                clock = 40;
                break;
        }
        coef_scaled = ((5 * (clock << 24)) / 2) / channel->center_freq;

        /* Get exponent
         * ALGO: coef_exp = 14 - highest set bit position */
        coef_exp = ilog2(coef_scaled);

        /* Doesn't make sense if it's zero*/
        if (!coef_scaled || !coef_exp)
                return -EINVAL;

        /* Note: we've shifted coef_scaled by 24 */
        coef_exp = 14 - (coef_exp - 24);


        /* Get mantissa (significant digits)
         * ALGO: coef_mant = floor(coef_scaled* 2^coef_exp+0.5) */
        coef_man = coef_scaled +
                (1 << (24 - coef_exp - 1));

        /* Calculate delta slope coefficient exponent
         * and mantissa (remove scaling) and set them on hw */
        ds_coef_man = coef_man >> (24 - coef_exp);
        ds_coef_exp = coef_exp - 16;

        AR5K_REG_WRITE_BITS(ah, AR5K_PHY_TIMING_3,
                AR5K_PHY_TIMING_3_DSC_MAN, ds_coef_man);
        AR5K_REG_WRITE_BITS(ah, AR5K_PHY_TIMING_3,
                AR5K_PHY_TIMING_3_DSC_EXP, ds_coef_exp);

        return 0;
}

/**
 * ath5k_hw_phy_disable() - Disable PHY
 * @ah: The &struct ath5k_hw
 */
int ath5k_hw_phy_disable(struct ath5k_hw *ah)
{
        /*Just a try M.F.*/
        ath5k_hw_reg_write(ah, AR5K_PHY_ACT_DISABLE, AR5K_PHY_ACT);

        return 0;
}

/**
 * ath5k_hw_wait_for_synth() - Wait for synth to settle
 * @ah: The &struct ath5k_hw
 * @channel: The &struct ieee80211_channel
 */
static void
ath5k_hw_wait_for_synth(struct ath5k_hw *ah,
                        struct ieee80211_channel *channel)
{
        /*
         * On 5211+ read activation -> rx delay
         * and use it (100ns steps).
         */
        if (ah->ah_version != AR5K_AR5210) {
                u32 delay;
                delay = ath5k_hw_reg_read(ah, AR5K_PHY_RX_DELAY) &
                        AR5K_PHY_RX_DELAY_M;
                delay = (channel->hw_value == AR5K_MODE_11B) ?
                        ((delay << 2) / 22) : (delay / 10);
                if (ah->ah_bwmode == AR5K_BWMODE_10MHZ)
                        delay = delay << 1;
                if (ah->ah_bwmode == AR5K_BWMODE_5MHZ)
                        delay = delay << 2;
                /* XXX: /2 on turbo ? Let's be safe
                 * for now */
                usleep_range(100 + delay, 100 + (2 * delay));
        } else {
                usleep_range(1000, 1500);
        }
}


/**********************\
* RF Gain optimization *
\**********************/

/**
 * DOC: RF Gain optimization
 *
 * This code is used to optimize RF gain on different environments
 * (temperature mostly) based on feedback from a power detector.
 *
 * It's only used on RF5111 and RF5112, later RF chips seem to have
 * auto adjustment on hw -notice they have a much smaller BANK 7 and
 * no gain optimization ladder-.
 *
 * For more infos check out this patent doc
 * "http://www.freepatentsonline.com/7400691.html"
 *
 * This paper describes power drops as seen on the receiver due to
 * probe packets
 * "http://www.cnri.dit.ie/publications/ICT08%20-%20Practical%20Issues
 * %20of%20Power%20Control.pdf"
 *
 * And this is the MadWiFi bug entry related to the above
 * "http://madwifi-project.org/ticket/1659"
 * with various measurements and diagrams
 */

/**
 * ath5k_hw_rfgain_opt_init() - Initialize ah_gain during attach
 * @ah: The &struct ath5k_hw
 */
int ath5k_hw_rfgain_opt_init(struct ath5k_hw *ah)
{
        /* Initialize the gain optimization values */
        switch (ah->ah_radio) {
        case AR5K_RF5111:
                ah->ah_gain.g_step_idx = rfgain_opt_5111.go_default;
                ah->ah_gain.g_low = 20;
                ah->ah_gain.g_high = 35;
                ah->ah_gain.g_state = AR5K_RFGAIN_ACTIVE;
                break;
        case AR5K_RF5112:
                ah->ah_gain.g_step_idx = rfgain_opt_5112.go_default;
                ah->ah_gain.g_low = 20;
                ah->ah_gain.g_high = 85;
                ah->ah_gain.g_state = AR5K_RFGAIN_ACTIVE;
                break;
        default:
                return -EINVAL;
        }

        return 0;
}

/**
 * ath5k_hw_request_rfgain_probe() - Request a PAPD probe packet
 * @ah: The &struct ath5k_hw
 *
 * Schedules a gain probe check on the next transmitted packet.
 * That means our next packet is going to be sent with lower
 * tx power and a Peak to Average Power Detector (PAPD) will try
 * to measure the gain.
 *
 * TODO: Force a tx packet (bypassing PCU arbitrator etc)
 * just after we enable the probe so that we don't mess with
 * standard traffic.
 */
static void
ath5k_hw_request_rfgain_probe(struct ath5k_hw *ah)
{

        /* Skip if gain calibration is inactive or
         * we already handle a probe request */
        if (ah->ah_gain.g_state != AR5K_RFGAIN_ACTIVE)
                return;

        /* Send the packet with 2dB below max power as
         * patent doc suggest */
        ath5k_hw_reg_write(ah, AR5K_REG_SM(ah->ah_txpower.txp_ofdm - 4,
                        AR5K_PHY_PAPD_PROBE_TXPOWER) |
                        AR5K_PHY_PAPD_PROBE_TX_NEXT, AR5K_PHY_PAPD_PROBE);

        ah->ah_gain.g_state = AR5K_RFGAIN_READ_REQUESTED;

}

/**
 * ath5k_hw_rf_gainf_corr() - Calculate Gain_F measurement correction
 * @ah: The &struct ath5k_hw
 *
 * Calculate Gain_F measurement correction
 * based on the current step for RF5112 rev. 2
 */
static u32
ath5k_hw_rf_gainf_corr(struct ath5k_hw *ah)
{
        u32 mix, step;
        const struct ath5k_gain_opt *go;
        const struct ath5k_gain_opt_step *g_step;
        const struct ath5k_rf_reg *rf_regs;

        /* Only RF5112 Rev. 2 supports it */
        if ((ah->ah_radio != AR5K_RF5112) ||
        (ah->ah_radio_5ghz_revision <= AR5K_SREV_RAD_5112A))
                return 0;

        go = &rfgain_opt_5112;
        rf_regs = rf_regs_5112a;
        ah->ah_rf_regs_count = ARRAY_SIZE(rf_regs_5112a);

        g_step = &go->go_step[ah->ah_gain.g_step_idx];

        if (ah->ah_rf_banks == NULL)
                return 0;

        ah->ah_gain.g_f_corr = 0;

        /* No VGA (Variable Gain Amplifier) override, skip */
        if (ath5k_hw_rfb_op(ah, rf_regs, 0, AR5K_RF_MIXVGA_OVR, false) != 1)
                return 0;

        /* Mix gain stepping */
        step = ath5k_hw_rfb_op(ah, rf_regs, 0, AR5K_RF_MIXGAIN_STEP, false);

        /* Mix gain override */
        mix = g_step->gos_param[0];

        switch (mix) {
        case 3:
                ah->ah_gain.g_f_corr = step * 2;
                break;
        case 2:
                ah->ah_gain.g_f_corr = (step - 5) * 2;
                break;
        case 1:
                ah->ah_gain.g_f_corr = step;
                break;
        default:
                ah->ah_gain.g_f_corr = 0;
                break;
        }

        return ah->ah_gain.g_f_corr;
}

/**
 * ath5k_hw_rf_check_gainf_readback() - Validate Gain_F feedback from detector
 * @ah: The &struct ath5k_hw
 *
 * Check if current gain_F measurement is in the range of our
 * power detector windows. If we get a measurement outside range
 * we know it's not accurate (detectors can't measure anything outside
 * their detection window) so we must ignore it.
 *
 * Returns true if readback was O.K. or false on failure
 */
static bool
ath5k_hw_rf_check_gainf_readback(struct ath5k_hw *ah)
{
        const struct ath5k_rf_reg *rf_regs;
        u32 step, mix_ovr, level[4];

        if (ah->ah_rf_banks == NULL)
                return false;

        if (ah->ah_radio == AR5K_RF5111) {

                rf_regs = rf_regs_5111;
                ah->ah_rf_regs_count = ARRAY_SIZE(rf_regs_5111);

                step = ath5k_hw_rfb_op(ah, rf_regs, 0, AR5K_RF_RFGAIN_STEP,
                        false);

                level[0] = 0;
                level[1] = (step == 63) ? 50 : step + 4;
                level[2] = (step != 63) ? 64 : level[0];
                level[3] = level[2] + 50;

                ah->ah_gain.g_high = level[3] -
                        (step == 63 ? AR5K_GAIN_DYN_ADJUST_HI_MARGIN : -5);
                ah->ah_gain.g_low = level[0] +
                        (step == 63 ? AR5K_GAIN_DYN_ADJUST_LO_MARGIN : 0);
        } else {

                rf_regs = rf_regs_5112;
                ah->ah_rf_regs_count = ARRAY_SIZE(rf_regs_5112);

                mix_ovr = ath5k_hw_rfb_op(ah, rf_regs, 0, AR5K_RF_MIXVGA_OVR,
                        false);

                level[0] = level[2] = 0;

                if (mix_ovr == 1) {
                        level[1] = level[3] = 83;
                } else {
                        level[1] = level[3] = 107;
                        ah->ah_gain.g_high = 55;
                }
        }

        return (ah->ah_gain.g_current >= level[0] &&
                        ah->ah_gain.g_current <= level[1]) ||
                (ah->ah_gain.g_current >= level[2] &&
                        ah->ah_gain.g_current <= level[3]);
}

/**
 * ath5k_hw_rf_gainf_adjust() - Perform Gain_F adjustment
 * @ah: The &struct ath5k_hw
 *
 * Choose the right target gain based on current gain
 * and RF gain optimization ladder
 */
static s8
ath5k_hw_rf_gainf_adjust(struct ath5k_hw *ah)
{
        const struct ath5k_gain_opt *go;
        const struct ath5k_gain_opt_step *g_step;
        int ret = 0;

        switch (ah->ah_radio) {
        case AR5K_RF5111:
                go = &rfgain_opt_5111;
                break;
        case AR5K_RF5112:
                go = &rfgain_opt_5112;
                break;
        default:
                return 0;
        }

        g_step = &go->go_step[ah->ah_gain.g_step_idx];

        if (ah->ah_gain.g_current >= ah->ah_gain.g_high) {

                /* Reached maximum */
                if (ah->ah_gain.g_step_idx == 0)
                        return -1;

                for (ah->ah_gain.g_target = ah->ah_gain.g_current;
                                ah->ah_gain.g_target >=  ah->ah_gain.g_high &&
                                ah->ah_gain.g_step_idx > 0;
                                g_step = &go->go_step[ah->ah_gain.g_step_idx])
                        ah->ah_gain.g_target -= 2 *
                            (go->go_step[--(ah->ah_gain.g_step_idx)].gos_gain -
                            g_step->gos_gain);

                ret = 1;
                goto done;
        }

        if (ah->ah_gain.g_current <= ah->ah_gain.g_low) {

                /* Reached minimum */
                if (ah->ah_gain.g_step_idx == (go->go_steps_count - 1))
                        return -2;

                for (ah->ah_gain.g_target = ah->ah_gain.g_current;
                                ah->ah_gain.g_target <= ah->ah_gain.g_low &&
                                ah->ah_gain.g_step_idx < go->go_steps_count - 1;
                                g_step = &go->go_step[ah->ah_gain.g_step_idx])
                        ah->ah_gain.g_target -= 2 *
                            (go->go_step[++ah->ah_gain.g_step_idx].gos_gain -
                            g_step->gos_gain);

                ret = 2;
                goto done;
        }

done:
        ATH5K_DBG(ah, ATH5K_DEBUG_CALIBRATE,
                "ret %d, gain step %u, current gain %u, target gain %u\n",
                ret, ah->ah_gain.g_step_idx, ah->ah_gain.g_current,
                ah->ah_gain.g_target);

        return ret;
}

/**
 * ath5k_hw_gainf_calibrate() - Do a gain_F calibration
 * @ah: The &struct ath5k_hw
 *
 * Main callback for thermal RF gain calibration engine
 * Check for a new gain reading and schedule an adjustment
 * if needed.
 *
 * Returns one of enum ath5k_rfgain codes
 */
enum ath5k_rfgain
ath5k_hw_gainf_calibrate(struct ath5k_hw *ah)
{
        u32 data, type;
        struct ath5k_eeprom_info *ee = &ah->ah_capabilities.cap_eeprom;

        if (ah->ah_rf_banks == NULL ||
        ah->ah_gain.g_state == AR5K_RFGAIN_INACTIVE)
                return AR5K_RFGAIN_INACTIVE;

        /* No check requested, either engine is inactive
         * or an adjustment is already requested */
        if (ah->ah_gain.g_state != AR5K_RFGAIN_READ_REQUESTED)
                goto done;

        /* Read the PAPD (Peak to Average Power Detector)
         * register */
        data = ath5k_hw_reg_read(ah, AR5K_PHY_PAPD_PROBE);

        /* No probe is scheduled, read gain_F measurement */
        if (!(data & AR5K_PHY_PAPD_PROBE_TX_NEXT)) {
                ah->ah_gain.g_current = data >> AR5K_PHY_PAPD_PROBE_GAINF_S;
                type = AR5K_REG_MS(data, AR5K_PHY_PAPD_PROBE_TYPE);

                /* If tx packet is CCK correct the gain_F measurement
                 * by cck ofdm gain delta */
                if (type == AR5K_PHY_PAPD_PROBE_TYPE_CCK) {
                        if (ah->ah_radio_5ghz_revision >= AR5K_SREV_RAD_5112A)
                                ah->ah_gain.g_current +=
                                        ee->ee_cck_ofdm_gain_delta;
                        else
                                ah->ah_gain.g_current +=
                                        AR5K_GAIN_CCK_PROBE_CORR;
                }

                /* Further correct gain_F measurement for
                 * RF5112A radios */
                if (ah->ah_radio_5ghz_revision >= AR5K_SREV_RAD_5112A) {
                        ath5k_hw_rf_gainf_corr(ah);
                        ah->ah_gain.g_current =
                                ah->ah_gain.g_current >= ah->ah_gain.g_f_corr ?
                                (ah->ah_gain.g_current - ah->ah_gain.g_f_corr) :
                                0;
                }

                /* Check if measurement is ok and if we need
                 * to adjust gain, schedule a gain adjustment,
                 * else switch back to the active state */
                if (ath5k_hw_rf_check_gainf_readback(ah) &&
                AR5K_GAIN_CHECK_ADJUST(&ah->ah_gain) &&
                ath5k_hw_rf_gainf_adjust(ah)) {
                        ah->ah_gain.g_state = AR5K_RFGAIN_NEED_CHANGE;
                } else {
                        ah->ah_gain.g_state = AR5K_RFGAIN_ACTIVE;
                }
        }

done:
        return ah->ah_gain.g_state;
}

/**
 * ath5k_hw_rfgain_init() - Write initial RF gain settings to hw
 * @ah: The &struct ath5k_hw
 * @band: One of enum nl80211_band
 *
 * Write initial RF gain table to set the RF sensitivity.
 *
 * NOTE: This one works on all RF chips and has nothing to do
 * with Gain_F calibration
 */
static int
ath5k_hw_rfgain_init(struct ath5k_hw *ah, enum nl80211_band band)
{
        const struct ath5k_ini_rfgain *ath5k_rfg;
        unsigned int i, size, index;

        switch (ah->ah_radio) {
        case AR5K_RF5111:
                ath5k_rfg = rfgain_5111;
                size = ARRAY_SIZE(rfgain_5111);
                break;
        case AR5K_RF5112:
                ath5k_rfg = rfgain_5112;
                size = ARRAY_SIZE(rfgain_5112);
                break;
        case AR5K_RF2413:
                ath5k_rfg = rfgain_2413;
                size = ARRAY_SIZE(rfgain_2413);
                break;
        case AR5K_RF2316:
                ath5k_rfg = rfgain_2316;
                size = ARRAY_SIZE(rfgain_2316);
                break;
        case AR5K_RF5413:
                ath5k_rfg = rfgain_5413;
                size = ARRAY_SIZE(rfgain_5413);
                break;
        case AR5K_RF2317:
        case AR5K_RF2425:
                ath5k_rfg = rfgain_2425;
                size = ARRAY_SIZE(rfgain_2425);
                break;
        default:
                return -EINVAL;
        }

        index = (band == NL80211_BAND_2GHZ) ? 1 : 0;

        for (i = 0; i < size; i++) {
                AR5K_REG_WAIT(i);
                ath5k_hw_reg_write(ah, ath5k_rfg[i].rfg_value[index],
                        (u32)ath5k_rfg[i].rfg_register);
        }

        return 0;
}


/********************\
* RF Registers setup *
\********************/

/**
 * ath5k_hw_rfregs_init() - Initialize RF register settings
 * @ah: The &struct ath5k_hw
 * @channel: The &struct ieee80211_channel
 * @mode: One of enum ath5k_driver_mode
 *
 * Setup RF registers by writing RF buffer on hw. For
 * more infos on this, check out rfbuffer.h
 */
static int
ath5k_hw_rfregs_init(struct ath5k_hw *ah,
                        struct ieee80211_channel *channel,
                        unsigned int mode)
{
        const struct ath5k_rf_reg *rf_regs;
        const struct ath5k_ini_rfbuffer *ini_rfb;
        const struct ath5k_gain_opt *go = NULL;
        const struct ath5k_gain_opt_step *g_step;
        struct ath5k_eeprom_info *ee = &ah->ah_capabilities.cap_eeprom;
        u8 ee_mode = 0;
        u32 *rfb;
        int i, obdb = -1, bank = -1;

        switch (ah->ah_radio) {
        case AR5K_RF5111:
                rf_regs = rf_regs_5111;
                ah->ah_rf_regs_count = ARRAY_SIZE(rf_regs_5111);
                ini_rfb = rfb_5111;
                ah->ah_rf_banks_size = ARRAY_SIZE(rfb_5111);
                go = &rfgain_opt_5111;
                break;
        case AR5K_RF5112:
                if (ah->ah_radio_5ghz_revision >= AR5K_SREV_RAD_5112A) {
                        rf_regs = rf_regs_5112a;
                        ah->ah_rf_regs_count = ARRAY_SIZE(rf_regs_5112a);
                        ini_rfb = rfb_5112a;
                        ah->ah_rf_banks_size = ARRAY_SIZE(rfb_5112a);
                } else {
                        rf_regs = rf_regs_5112;
                        ah->ah_rf_regs_count = ARRAY_SIZE(rf_regs_5112);
                        ini_rfb = rfb_5112;
                        ah->ah_rf_banks_size = ARRAY_SIZE(rfb_5112);
                }
                go = &rfgain_opt_5112;
                break;
        case AR5K_RF2413:
                rf_regs = rf_regs_2413;
                ah->ah_rf_regs_count = ARRAY_SIZE(rf_regs_2413);
                ini_rfb = rfb_2413;
                ah->ah_rf_banks_size = ARRAY_SIZE(rfb_2413);
                break;
        case AR5K_RF2316:
                rf_regs = rf_regs_2316;
                ah->ah_rf_regs_count = ARRAY_SIZE(rf_regs_2316);
                ini_rfb = rfb_2316;
                ah->ah_rf_banks_size = ARRAY_SIZE(rfb_2316);
                break;
        case AR5K_RF5413:
                rf_regs = rf_regs_5413;
                ah->ah_rf_regs_count = ARRAY_SIZE(rf_regs_5413);
                ini_rfb = rfb_5413;
                ah->ah_rf_banks_size = ARRAY_SIZE(rfb_5413);
                break;
        case AR5K_RF2317:
                rf_regs = rf_regs_2425;
                ah->ah_rf_regs_count = ARRAY_SIZE(rf_regs_2425);
                ini_rfb = rfb_2317;
                ah->ah_rf_banks_size = ARRAY_SIZE(rfb_2317);
                break;
        case AR5K_RF2425:
                rf_regs = rf_regs_2425;
                ah->ah_rf_regs_count = ARRAY_SIZE(rf_regs_2425);
                if (ah->ah_mac_srev < AR5K_SREV_AR2417) {
                        ini_rfb = rfb_2425;
                        ah->ah_rf_banks_size = ARRAY_SIZE(rfb_2425);
                } else {
                        ini_rfb = rfb_2417;
                        ah->ah_rf_banks_size = ARRAY_SIZE(rfb_2417);
                }
                break;
        default:
                return -EINVAL;
        }

        /* If it's the first time we set RF buffer, allocate
         * ah->ah_rf_banks based on ah->ah_rf_banks_size
         * we set above */
        if (ah->ah_rf_banks == NULL) {
                ah->ah_rf_banks = kmalloc_array(ah->ah_rf_banks_size,
                                                                sizeof(u32),
                                                                GFP_KERNEL);
                if (ah->ah_rf_banks == NULL) {
                        ATH5K_ERR(ah, "out of memory\n");
                        return -ENOMEM;
                }
        }

        /* Copy values to modify them */
        rfb = ah->ah_rf_banks;

        for (i = 0; i < ah->ah_rf_banks_size; i++) {
                if (ini_rfb[i].rfb_bank >= AR5K_MAX_RF_BANKS) {
                        ATH5K_ERR(ah, "invalid bank\n");
                        return -EINVAL;
                }

                /* Bank changed, write down the offset */
                if (bank != ini_rfb[i].rfb_bank) {
                        bank = ini_rfb[i].rfb_bank;
                        ah->ah_offset[bank] = i;
                }

                rfb[i] = ini_rfb[i].rfb_mode_data[mode];
        }

        /* Set Output and Driver bias current (OB/DB) */
        if (channel->band == NL80211_BAND_2GHZ) {

                if (channel->hw_value == AR5K_MODE_11B)
                        ee_mode = AR5K_EEPROM_MODE_11B;
                else
                        ee_mode = AR5K_EEPROM_MODE_11G;

                /* For RF511X/RF211X combination we
                 * use b_OB and b_DB parameters stored
                 * in eeprom on ee->ee_ob[ee_mode][0]
                 *
                 * For all other chips we use OB/DB for 2GHz
                 * stored in the b/g modal section just like
                 * 802.11a on ee->ee_ob[ee_mode][1] */
                if ((ah->ah_radio == AR5K_RF5111) ||
                (ah->ah_radio == AR5K_RF5112))
                        obdb = 0;
                else
                        obdb = 1;

                ath5k_hw_rfb_op(ah, rf_regs, ee->ee_ob[ee_mode][obdb],
                                                AR5K_RF_OB_2GHZ, true);

                ath5k_hw_rfb_op(ah, rf_regs, ee->ee_db[ee_mode][obdb],
                                                AR5K_RF_DB_2GHZ, true);

        /* RF5111 always needs OB/DB for 5GHz, even if we use 2GHz */
        } else if ((channel->band == NL80211_BAND_5GHZ) ||
                        (ah->ah_radio == AR5K_RF5111)) {

                /* For 11a, Turbo and XR we need to choose
                 * OB/DB based on frequency range */
                ee_mode = AR5K_EEPROM_MODE_11A;
                obdb =   channel->center_freq >= 5725 ? 3 :
                        (channel->center_freq >= 5500 ? 2 :
                        (channel->center_freq >= 5260 ? 1 :
                         (channel->center_freq > 4000 ? 0 : -1)));

                if (obdb < 0)
                        return -EINVAL;

                ath5k_hw_rfb_op(ah, rf_regs, ee->ee_ob[ee_mode][obdb],
                                                AR5K_RF_OB_5GHZ, true);

                ath5k_hw_rfb_op(ah, rf_regs, ee->ee_db[ee_mode][obdb],
                                                AR5K_RF_DB_5GHZ, true);
        }

        g_step = &go->go_step[ah->ah_gain.g_step_idx];

        /* Set turbo mode (N/A on RF5413) */
        if ((ah->ah_bwmode == AR5K_BWMODE_40MHZ) &&
        (ah->ah_radio != AR5K_RF5413))
                ath5k_hw_rfb_op(ah, rf_regs, 1, AR5K_RF_TURBO, false);

        /* Bank Modifications (chip-specific) */
        if (ah->ah_radio == AR5K_RF5111) {

                /* Set gain_F settings according to current step */
                if (channel->hw_value != AR5K_MODE_11B) {

                        AR5K_REG_WRITE_BITS(ah, AR5K_PHY_FRAME_CTL,
                                        AR5K_PHY_FRAME_CTL_TX_CLIP,
                                        g_step->gos_param[0]);

                        ath5k_hw_rfb_op(ah, rf_regs, g_step->gos_param[1],
                                                        AR5K_RF_PWD_90, true);

                        ath5k_hw_rfb_op(ah, rf_regs, g_step->gos_param[2],
                                                        AR5K_RF_PWD_84, true);

                        ath5k_hw_rfb_op(ah, rf_regs, g_step->gos_param[3],
                                                AR5K_RF_RFGAIN_SEL, true);

                        /* We programmed gain_F parameters, switch back
                         * to active state */
                        ah->ah_gain.g_state = AR5K_RFGAIN_ACTIVE;

                }

                /* Bank 6/7 setup */

                ath5k_hw_rfb_op(ah, rf_regs, !ee->ee_xpd[ee_mode],
                                                AR5K_RF_PWD_XPD, true);

                ath5k_hw_rfb_op(ah, rf_regs, ee->ee_x_gain[ee_mode],
                                                AR5K_RF_XPD_GAIN, true);

                ath5k_hw_rfb_op(ah, rf_regs, ee->ee_i_gain[ee_mode],
                                                AR5K_RF_GAIN_I, true);

                ath5k_hw_rfb_op(ah, rf_regs, ee->ee_xpd[ee_mode],
                                                AR5K_RF_PLO_SEL, true);

                /* Tweak power detectors for half/quarter rate support */
                if (ah->ah_bwmode == AR5K_BWMODE_5MHZ ||
                ah->ah_bwmode == AR5K_BWMODE_10MHZ) {
                        u8 wait_i;

                        ath5k_hw_rfb_op(ah, rf_regs, 0x1f,
                                                AR5K_RF_WAIT_S, true);

                        wait_i = (ah->ah_bwmode == AR5K_BWMODE_5MHZ) ?
                                                        0x1f : 0x10;

                        ath5k_hw_rfb_op(ah, rf_regs, wait_i,
                                                AR5K_RF_WAIT_I, true);
                        ath5k_hw_rfb_op(ah, rf_regs, 3,
                                                AR5K_RF_MAX_TIME, true);

                }
        }

        if (ah->ah_radio == AR5K_RF5112) {

                /* Set gain_F settings according to current step */
                if (channel->hw_value != AR5K_MODE_11B) {

                        ath5k_hw_rfb_op(ah, rf_regs, g_step->gos_param[0],
                                                AR5K_RF_MIXGAIN_OVR, true);

                        ath5k_hw_rfb_op(ah, rf_regs, g_step->gos_param[1],
                                                AR5K_RF_PWD_138, true);

                        ath5k_hw_rfb_op(ah, rf_regs, g_step->gos_param[2],
                                                AR5K_RF_PWD_137, true);

                        ath5k_hw_rfb_op(ah, rf_regs, g_step->gos_param[3],
                                                AR5K_RF_PWD_136, true);

                        ath5k_hw_rfb_op(ah, rf_regs, g_step->gos_param[4],
                                                AR5K_RF_PWD_132, true);

                        ath5k_hw_rfb_op(ah, rf_regs, g_step->gos_param[5],
                                                AR5K_RF_PWD_131, true);

                        ath5k_hw_rfb_op(ah, rf_regs, g_step->gos_param[6],
                                                AR5K_RF_PWD_130, true);

                        /* We programmed gain_F parameters, switch back
                         * to active state */
                        ah->ah_gain.g_state = AR5K_RFGAIN_ACTIVE;
                }

                /* Bank 6/7 setup */

                ath5k_hw_rfb_op(ah, rf_regs, ee->ee_xpd[ee_mode],
                                                AR5K_RF_XPD_SEL, true);

                if (ah->ah_radio_5ghz_revision < AR5K_SREV_RAD_5112A) {
                        /* Rev. 1 supports only one xpd */
                        ath5k_hw_rfb_op(ah, rf_regs,
                                                ee->ee_x_gain[ee_mode],
                                                AR5K_RF_XPD_GAIN, true);

                } else {
                        u8 *pdg_curve_to_idx = ee->ee_pdc_to_idx[ee_mode];
                        if (ee->ee_pd_gains[ee_mode] > 1) {
                                ath5k_hw_rfb_op(ah, rf_regs,
                                                pdg_curve_to_idx[0],
                                                AR5K_RF_PD_GAIN_LO, true);
                                ath5k_hw_rfb_op(ah, rf_regs,
                                                pdg_curve_to_idx[1],
                                                AR5K_RF_PD_GAIN_HI, true);
                        } else {
                                ath5k_hw_rfb_op(ah, rf_regs,
                                                pdg_curve_to_idx[0],
                                                AR5K_RF_PD_GAIN_LO, true);
                                ath5k_hw_rfb_op(ah, rf_regs,
                                                pdg_curve_to_idx[0],
                                                AR5K_RF_PD_GAIN_HI, true);
                        }

                        /* Lower synth voltage on Rev 2 */
                        if (ah->ah_radio == AR5K_RF5112 &&
                            (ah->ah_radio_5ghz_revision & AR5K_SREV_REV) > 0) {
                                ath5k_hw_rfb_op(ah, rf_regs, 2,
                                                AR5K_RF_HIGH_VC_CP, true);

                                ath5k_hw_rfb_op(ah, rf_regs, 2,
                                                AR5K_RF_MID_VC_CP, true);

                                ath5k_hw_rfb_op(ah, rf_regs, 2,
                                                AR5K_RF_LOW_VC_CP, true);

                                ath5k_hw_rfb_op(ah, rf_regs, 2,
                                                AR5K_RF_PUSH_UP, true);
                        }

                        /* Decrease power consumption on 5213+ BaseBand */
                        if (ah->ah_phy_revision >= AR5K_SREV_PHY_5212A) {
                                ath5k_hw_rfb_op(ah, rf_regs, 1,
                                                AR5K_RF_PAD2GND, true);

                                ath5k_hw_rfb_op(ah, rf_regs, 1,
                                                AR5K_RF_XB2_LVL, true);

                                ath5k_hw_rfb_op(ah, rf_regs, 1,
                                                AR5K_RF_XB5_LVL, true);

                                ath5k_hw_rfb_op(ah, rf_regs, 1,
                                                AR5K_RF_PWD_167, true);

                                ath5k_hw_rfb_op(ah, rf_regs, 1,
                                                AR5K_RF_PWD_166, true);
                        }
                }

                ath5k_hw_rfb_op(ah, rf_regs, ee->ee_i_gain[ee_mode],
                                                AR5K_RF_GAIN_I, true);

                /* Tweak power detector for half/quarter rates */
                if (ah->ah_bwmode == AR5K_BWMODE_5MHZ ||
                ah->ah_bwmode == AR5K_BWMODE_10MHZ) {
                        u8 pd_delay;

                        pd_delay = (ah->ah_bwmode == AR5K_BWMODE_5MHZ) ?
                                                        0xf : 0x8;

                        ath5k_hw_rfb_op(ah, rf_regs, pd_delay,
                                                AR5K_RF_PD_PERIOD_A, true);
                        ath5k_hw_rfb_op(ah, rf_regs, 0xf,
                                                AR5K_RF_PD_DELAY_A, true);

                }
        }

        if (ah->ah_radio == AR5K_RF5413 &&
        channel->band == NL80211_BAND_2GHZ) {

                ath5k_hw_rfb_op(ah, rf_regs, 1, AR5K_RF_DERBY_CHAN_SEL_MODE,
                                                                        true);

                /* Set optimum value for early revisions (on pci-e chips) */
                if (ah->ah_mac_srev >= AR5K_SREV_AR5424 &&
                ah->ah_mac_srev < AR5K_SREV_AR5413)
                        ath5k_hw_rfb_op(ah, rf_regs, ath5k_hw_bitswap(6, 3),
                                                AR5K_RF_PWD_ICLOBUF_2G, true);

        }

        /* Write RF banks on hw */
        for (i = 0; i < ah->ah_rf_banks_size; i++) {
                AR5K_REG_WAIT(i);
                ath5k_hw_reg_write(ah, rfb[i], ini_rfb[i].rfb_ctrl_register);
        }

        return 0;
}


/**************************\
  PHY/RF channel functions
\**************************/

/**
 * ath5k_hw_rf5110_chan2athchan() - Convert channel freq on RF5110
 * @channel: The &struct ieee80211_channel
 *
 * Map channel frequency to IEEE channel number and convert it
 * to an internal channel value used by the RF5110 chipset.
 */
static u32
ath5k_hw_rf5110_chan2athchan(struct ieee80211_channel *channel)
{
        u32 athchan;

        athchan = (ath5k_hw_bitswap(
                        (ieee80211_frequency_to_channel(
                                channel->center_freq) - 24) / 2, 5)
                                << 1) | (1 << 6) | 0x1;
        return athchan;
}

/**
 * ath5k_hw_rf5110_channel() - Set channel frequency on RF5110
 * @ah: The &struct ath5k_hw
 * @channel: The &struct ieee80211_channel
 */
static int
ath5k_hw_rf5110_channel(struct ath5k_hw *ah,
                struct ieee80211_channel *channel)
{
        u32 data;

        /*
         * Set the channel and wait
         */
        data = ath5k_hw_rf5110_chan2athchan(channel);
        ath5k_hw_reg_write(ah, data, AR5K_RF_BUFFER);
        ath5k_hw_reg_write(ah, 0, AR5K_RF_BUFFER_CONTROL_0);
        usleep_range(1000, 1500);

        return 0;
}

/**
 * ath5k_hw_rf5111_chan2athchan() - Handle 2GHz channels on RF5111/2111
 * @ieee: IEEE channel number
 * @athchan: The &struct ath5k_athchan_2ghz
 *
 * In order to enable the RF2111 frequency converter on RF5111/2111 setups
 * we need to add some offsets and extra flags to the data values we pass
 * on to the PHY. So for every 2GHz channel this function gets called
 * to do the conversion.
 */
static int
ath5k_hw_rf5111_chan2athchan(unsigned int ieee,
                struct ath5k_athchan_2ghz *athchan)
{
        int channel;

        /* Cast this value to catch negative channel numbers (>= -19) */
        channel = (int)ieee;

        /*
         * Map 2GHz IEEE channel to 5GHz Atheros channel
         */
        if (channel <= 13) {
                athchan->a2_athchan = 115 + channel;
                athchan->a2_flags = 0x46;
        } else if (channel == 14) {
                athchan->a2_athchan = 124;
                athchan->a2_flags = 0x44;
        } else if (channel >= 15 && channel <= 26) {
                athchan->a2_athchan = ((channel - 14) * 4) + 132;
                athchan->a2_flags = 0x46;
        } else
                return -EINVAL;

        return 0;
}

/**
 * ath5k_hw_rf5111_channel() - Set channel frequency on RF5111/2111
 * @ah: The &struct ath5k_hw
 * @channel: The &struct ieee80211_channel
 */
static int
ath5k_hw_rf5111_channel(struct ath5k_hw *ah,
                struct ieee80211_channel *channel)
{
        struct ath5k_athchan_2ghz ath5k_channel_2ghz;
        unsigned int ath5k_channel =
                ieee80211_frequency_to_channel(channel->center_freq);
        u32 data0, data1, clock;
        int ret;

        /*
         * Set the channel on the RF5111 radio
         */
        data0 = data1 = 0;

        if (channel->band == NL80211_BAND_2GHZ) {
                /* Map 2GHz channel to 5GHz Atheros channel ID */
                ret = ath5k_hw_rf5111_chan2athchan(
                        ieee80211_frequency_to_channel(channel->center_freq),
                        &ath5k_channel_2ghz);
                if (ret)
                        return ret;

                ath5k_channel = ath5k_channel_2ghz.a2_athchan;
                data0 = ((ath5k_hw_bitswap(ath5k_channel_2ghz.a2_flags, 8) & 0xff)
                    << 5) | (1 << 4);
        }

        if (ath5k_channel < 145 || !(ath5k_channel & 1)) {
                clock = 1;
                data1 = ((ath5k_hw_bitswap(ath5k_channel - 24, 8) & 0xff) << 2) |
                        (clock << 1) | (1 << 10) | 1;
        } else {
                clock = 0;
                data1 = ((ath5k_hw_bitswap((ath5k_channel - 24) / 2, 8) & 0xff)
                        << 2) | (clock << 1) | (1 << 10) | 1;
        }

        ath5k_hw_reg_write(ah, (data1 & 0xff) | ((data0 & 0xff) << 8),
                        AR5K_RF_BUFFER);
        ath5k_hw_reg_write(ah, ((data1 >> 8) & 0xff) | (data0 & 0xff00),
                        AR5K_RF_BUFFER_CONTROL_3);

        return 0;
}

/**
 * ath5k_hw_rf5112_channel() - Set channel frequency on 5112 and newer
 * @ah: The &struct ath5k_hw
 * @channel: The &struct ieee80211_channel
 *
 * On RF5112/2112 and newer we don't need to do any conversion.
 * We pass the frequency value after a few modifications to the
 * chip directly.
 *
 * NOTE: Make sure channel frequency given is within our range or else
 * we might damage the chip ! Use ath5k_channel_ok before calling this one.
 */
static int
ath5k_hw_rf5112_channel(struct ath5k_hw *ah,
                struct ieee80211_channel *channel)
{
        u32 data, data0, data1, data2;
        u16 c;

        data = data0 = data1 = data2 = 0;
        c = channel->center_freq;

        /* My guess based on code:
         * 2GHz RF has 2 synth modes, one with a Local Oscillator
         * at 2224Hz and one with a LO at 2192Hz. IF is 1520Hz
         * (3040/2). data0 is used to set the PLL divider and data1
         * selects synth mode. */
        if (c < 4800) {
                /* Channel 14 and all frequencies with 2Hz spacing
                 * below/above (non-standard channels) */
                if (!((c - 2224) % 5)) {
                        /* Same as (c - 2224) / 5 */
                        data0 = ((2 * (c - 704)) - 3040) / 10;
                        data1 = 1;
                /* Channel 1 and all frequencies with 5Hz spacing
                 * below/above (standard channels without channel 14) */
                } else if (!((c - 2192) % 5)) {
                        /* Same as (c - 2192) / 5 */
                        data0 = ((2 * (c - 672)) - 3040) / 10;
                        data1 = 0;
                } else
                        return -EINVAL;

                data0 = ath5k_hw_bitswap((data0 << 2) & 0xff, 8);
        /* This is more complex, we have a single synthesizer with
         * 4 reference clock settings (?) based on frequency spacing
         * and set using data2. LO is at 4800Hz and data0 is again used
         * to set some divider.
         *
         * NOTE: There is an old atheros presentation at Stanford
         * that mentions a method called dual direct conversion
         * with 1GHz sliding IF for RF5110. Maybe that's what we
         * have here, or an updated version. */
        } else if ((c % 5) != 2 || c > 5435) {
                if (!(c % 20) && c >= 5120) {
                        data0 = ath5k_hw_bitswap(((c - 4800) / 20 << 2), 8);
                        data2 = ath5k_hw_bitswap(3, 2);
                } else if (!(c % 10)) {
                        data0 = ath5k_hw_bitswap(((c - 4800) / 10 << 1), 8);
                        data2 = ath5k_hw_bitswap(2, 2);
                } else if (!(c % 5)) {
                        data0 = ath5k_hw_bitswap((c - 4800) / 5, 8);
                        data2 = ath5k_hw_bitswap(1, 2);
                } else
                        return -EINVAL;
        } else {
                data0 = ath5k_hw_bitswap((10 * (c - 2 - 4800)) / 25 + 1, 8);
                data2 = ath5k_hw_bitswap(0, 2);
        }

        data = (data0 << 4) | (data1 << 1) | (data2 << 2) | 0x1001;

        ath5k_hw_reg_write(ah, data & 0xff, AR5K_RF_BUFFER);
        ath5k_hw_reg_write(ah, (data >> 8) & 0x7f, AR5K_RF_BUFFER_CONTROL_5);

        return 0;
}

/**
 * ath5k_hw_rf2425_channel() - Set channel frequency on RF2425
 * @ah: The &struct ath5k_hw
 * @channel: The &struct ieee80211_channel
 *
 * AR2425/2417 have a different 2GHz RF so code changes
 * a little bit from RF5112.
 */
static int
ath5k_hw_rf2425_channel(struct ath5k_hw *ah,
                struct ieee80211_channel *channel)
{
        u32 data, data0, data2;
        u16 c;

        data = data0 = data2 = 0;
        c = channel->center_freq;

        if (c < 4800) {
                data0 = ath5k_hw_bitswap((c - 2272), 8);
                data2 = 0;
        /* ? 5GHz ? */
        } else if ((c % 5) != 2 || c > 5435) {
                if (!(c % 20) && c < 5120)
                        data0 = ath5k_hw_bitswap(((c - 4800) / 20 << 2), 8);
                else if (!(c % 10))
                        data0 = ath5k_hw_bitswap(((c - 4800) / 10 << 1), 8);
                else if (!(c % 5))
                        data0 = ath5k_hw_bitswap((c - 4800) / 5, 8);
                else
                        return -EINVAL;
                data2 = ath5k_hw_bitswap(1, 2);
        } else {
                data0 = ath5k_hw_bitswap((10 * (c - 2 - 4800)) / 25 + 1, 8);
                data2 = ath5k_hw_bitswap(0, 2);
        }

        data = (data0 << 4) | data2 << 2 | 0x1001;

        ath5k_hw_reg_write(ah, data & 0xff, AR5K_RF_BUFFER);
        ath5k_hw_reg_write(ah, (data >> 8) & 0x7f, AR5K_RF_BUFFER_CONTROL_5);

        return 0;
}

/**
 * ath5k_hw_channel() - Set a channel on the radio chip
 * @ah: The &struct ath5k_hw
 * @channel: The &struct ieee80211_channel
 *
 * This is the main function called to set a channel on the
 * radio chip based on the radio chip version.
 */
static int
ath5k_hw_channel(struct ath5k_hw *ah,
                struct ieee80211_channel *channel)
{
        int ret;
        /*
         * Check bounds supported by the PHY (we don't care about regulatory
         * restrictions at this point).
         */
        if (!ath5k_channel_ok(ah, channel)) {
                ATH5K_ERR(ah,
                        "channel frequency (%u MHz) out of supported "
                        "band range\n",
                        channel->center_freq);
                return -EINVAL;
        }

        /*
         * Set the channel and wait
         */
        switch (ah->ah_radio) {
        case AR5K_RF5110:
                ret = ath5k_hw_rf5110_channel(ah, channel);
                break;
        case AR5K_RF5111:
                ret = ath5k_hw_rf5111_channel(ah, channel);
                break;
        case AR5K_RF2317:
        case AR5K_RF2425:
                ret = ath5k_hw_rf2425_channel(ah, channel);
                break;
        default:
                ret = ath5k_hw_rf5112_channel(ah, channel);
                break;
        }

        if (ret)
                return ret;

        /* Set JAPAN setting for channel 14 */
        if (channel->center_freq == 2484) {
                AR5K_REG_ENABLE_BITS(ah, AR5K_PHY_CCKTXCTL,
                                AR5K_PHY_CCKTXCTL_JAPAN);
        } else {
                AR5K_REG_ENABLE_BITS(ah, AR5K_PHY_CCKTXCTL,
                                AR5K_PHY_CCKTXCTL_WORLD);
        }

        ah->ah_current_channel = channel;

        return 0;
}


/*****************\
  PHY calibration
\*****************/

/**
 * DOC: PHY Calibration routines
 *
 * Noise floor calibration: When we tell the hardware to
 * perform a noise floor calibration by setting the
 * AR5K_PHY_AGCCTL_NF bit on AR5K_PHY_AGCCTL, it will periodically
 * sample-and-hold the minimum noise level seen at the antennas.
 * This value is then stored in a ring buffer of recently measured
 * noise floor values so we have a moving window of the last few
 * samples. The median of the values in the history is then loaded
 * into the hardware for its own use for RSSI and CCA measurements.
 * This type of calibration doesn't interfere with traffic.
 *
 * AGC calibration: When we tell the hardware to perform
 * an AGC (Automatic Gain Control) calibration by setting the
 * AR5K_PHY_AGCCTL_CAL, hw disconnects the antennas and does
 * a calibration on the DC offsets of ADCs. During this period
 * rx/tx gets disabled so we have to deal with it on the driver
 * part.
 *
 * I/Q calibration: When we tell the hardware to perform
 * an I/Q calibration, it tries to correct I/Q imbalance and
 * fix QAM constellation by sampling data from rxed frames.
 * It doesn't interfere with traffic.
 *
 * For more infos on AGC and I/Q calibration check out patent doc
 * #03/094463.
 */

/**
 * ath5k_hw_read_measured_noise_floor() - Read measured NF from hw
 * @ah: The &struct ath5k_hw
 */
static s32
ath5k_hw_read_measured_noise_floor(struct ath5k_hw *ah)
{
        s32 val;

        val = ath5k_hw_reg_read(ah, AR5K_PHY_NF);
        return sign_extend32(AR5K_REG_MS(val, AR5K_PHY_NF_MINCCA_PWR), 8);
}

/**
 * ath5k_hw_init_nfcal_hist() - Initialize NF calibration history buffer
 * @ah: The &struct ath5k_hw
 */
void
ath5k_hw_init_nfcal_hist(struct ath5k_hw *ah)
{
        int i;

        ah->ah_nfcal_hist.index = 0;
        for (i = 0; i < ATH5K_NF_CAL_HIST_MAX; i++)
                ah->ah_nfcal_hist.nfval[i] = AR5K_TUNE_CCA_MAX_GOOD_VALUE;
}

/**
 * ath5k_hw_update_nfcal_hist() - Update NF calibration history buffer
 * @ah: The &struct ath5k_hw
 * @noise_floor: The NF we got from hw
 */
static void ath5k_hw_update_nfcal_hist(struct ath5k_hw *ah, s16 noise_floor)
{
        struct ath5k_nfcal_hist *hist = &ah->ah_nfcal_hist;
        hist->index = (hist->index + 1) & (ATH5K_NF_CAL_HIST_MAX - 1);
        hist->nfval[hist->index] = noise_floor;
}

/**
 * ath5k_hw_get_median_noise_floor() - Get median NF from history buffer
 * @ah: The &struct ath5k_hw
 */
static s16
ath5k_hw_get_median_noise_floor(struct ath5k_hw *ah)
{
        s16 sort[ATH5K_NF_CAL_HIST_MAX];
        s16 tmp;
        int i, j;

        memcpy(sort, ah->ah_nfcal_hist.nfval, sizeof(sort));
        for (i = 0; i < ATH5K_NF_CAL_HIST_MAX - 1; i++) {
                for (j = 1; j < ATH5K_NF_CAL_HIST_MAX - i; j++) {
                        if (sort[j] > sort[j - 1]) {
                                tmp = sort[j];
                                sort[j] = sort[j - 1];
                                sort[j - 1] = tmp;
                        }
                }
        }
        for (i = 0; i < ATH5K_NF_CAL_HIST_MAX; i++) {
                ATH5K_DBG(ah, ATH5K_DEBUG_CALIBRATE,
                        "cal %d:%d\n", i, sort[i]);
        }
        return sort[(ATH5K_NF_CAL_HIST_MAX - 1) / 2];
}

/**
 * ath5k_hw_update_noise_floor() - Update NF on hardware
 * @ah: The &struct ath5k_hw
 *
 * This is the main function we call to perform a NF calibration,
 * it reads NF from hardware, calculates the median and updates
 * NF on hw.
 */
void
ath5k_hw_update_noise_floor(struct ath5k_hw *ah)
{
        struct ath5k_eeprom_info *ee = &ah->ah_capabilities.cap_eeprom;
        u32 val;
        s16 nf, threshold;
        u8 ee_mode;

        /* keep last value if calibration hasn't completed */
        if (ath5k_hw_reg_read(ah, AR5K_PHY_AGCCTL) & AR5K_PHY_AGCCTL_NF) {
                ATH5K_DBG(ah, ATH5K_DEBUG_CALIBRATE,
                        "NF did not complete in calibration window\n");

                return;
        }

        ah->ah_cal_mask |= AR5K_CALIBRATION_NF;

        ee_mode = ath5k_eeprom_mode_from_channel(ah, ah->ah_current_channel);

        /* completed NF calibration, test threshold */
        nf = ath5k_hw_read_measured_noise_floor(ah);
        threshold = ee->ee_noise_floor_thr[ee_mode];

        if (nf > threshold) {
                ATH5K_DBG(ah, ATH5K_DEBUG_CALIBRATE,
                        "noise floor failure detected; "
                        "read %d, threshold %d\n",
                        nf, threshold);

                nf = AR5K_TUNE_CCA_MAX_GOOD_VALUE;
        }

        ath5k_hw_update_nfcal_hist(ah, nf);
        nf = ath5k_hw_get_median_noise_floor(ah);

        /* load noise floor (in .5 dBm) so the hardware will use it */
        val = ath5k_hw_reg_read(ah, AR5K_PHY_NF) & ~AR5K_PHY_NF_M;
        val |= (nf * 2) & AR5K_PHY_NF_M;
        ath5k_hw_reg_write(ah, val, AR5K_PHY_NF);

        AR5K_REG_MASKED_BITS(ah, AR5K_PHY_AGCCTL, AR5K_PHY_AGCCTL_NF,
                ~(AR5K_PHY_AGCCTL_NF_EN | AR5K_PHY_AGCCTL_NF_NOUPDATE));

        ath5k_hw_register_timeout(ah, AR5K_PHY_AGCCTL, AR5K_PHY_AGCCTL_NF,
                0, false);

        /*
         * Load a high max CCA Power value (-50 dBm in .5 dBm units)
         * so that we're not capped by the median we just loaded.
         * This will be used as the initial value for the next noise
         * floor calibration.
         */
        val = (val & ~AR5K_PHY_NF_M) | ((-50 * 2) & AR5K_PHY_NF_M);
        ath5k_hw_reg_write(ah, val, AR5K_PHY_NF);
        AR5K_REG_ENABLE_BITS(ah, AR5K_PHY_AGCCTL,
                AR5K_PHY_AGCCTL_NF_EN |
                AR5K_PHY_AGCCTL_NF_NOUPDATE |
                AR5K_PHY_AGCCTL_NF);

        ah->ah_noise_floor = nf;

        ah->ah_cal_mask &= ~AR5K_CALIBRATION_NF;

        ATH5K_DBG(ah, ATH5K_DEBUG_CALIBRATE,
                "noise floor calibrated: %d\n", nf);
}

/**
 * ath5k_hw_rf5110_calibrate() - Perform a PHY calibration on RF5110
 * @ah: The &struct ath5k_hw
 * @channel: The &struct ieee80211_channel
 *
 * Do a complete PHY calibration (AGC + NF + I/Q) on RF5110
 */
static int
ath5k_hw_rf5110_calibrate(struct ath5k_hw *ah,
                struct ieee80211_channel *channel)
{
        u32 phy_sig, phy_agc, phy_sat, beacon;
        int ret;

        if (!(ah->ah_cal_mask & AR5K_CALIBRATION_FULL))
                return 0;

        /*
         * Disable beacons and RX/TX queues, wait
         */
        AR5K_REG_ENABLE_BITS(ah, AR5K_DIAG_SW_5210,
                AR5K_DIAG_SW_DIS_TX_5210 | AR5K_DIAG_SW_DIS_RX_5210);
        beacon = ath5k_hw_reg_read(ah, AR5K_BEACON_5210);
        ath5k_hw_reg_write(ah, beacon & ~AR5K_BEACON_ENABLE, AR5K_BEACON_5210);

        usleep_range(2000, 2500);

        /*
         * Set the channel (with AGC turned off)
         */
        AR5K_REG_ENABLE_BITS(ah, AR5K_PHY_AGC, AR5K_PHY_AGC_DISABLE);
        udelay(10);
        ret = ath5k_hw_channel(ah, channel);

        /*
         * Activate PHY and wait
         */
        ath5k_hw_reg_write(ah, AR5K_PHY_ACT_ENABLE, AR5K_PHY_ACT);
        usleep_range(1000, 1500);

        AR5K_REG_DISABLE_BITS(ah, AR5K_PHY_AGC, AR5K_PHY_AGC_DISABLE);

        if (ret)
                return ret;

        /*
         * Calibrate the radio chip
         */

        /* Remember normal state */
        phy_sig = ath5k_hw_reg_read(ah, AR5K_PHY_SIG);
        phy_agc = ath5k_hw_reg_read(ah, AR5K_PHY_AGCCOARSE);
        phy_sat = ath5k_hw_reg_read(ah, AR5K_PHY_ADCSAT);

        /* Update radio registers */
        ath5k_hw_reg_write(ah, (phy_sig & ~(AR5K_PHY_SIG_FIRPWR)) |
                AR5K_REG_SM(-1, AR5K_PHY_SIG_FIRPWR), AR5K_PHY_SIG);

        ath5k_hw_reg_write(ah, (phy_agc & ~(AR5K_PHY_AGCCOARSE_HI |
                        AR5K_PHY_AGCCOARSE_LO)) |
                AR5K_REG_SM(-1, AR5K_PHY_AGCCOARSE_HI) |
                AR5K_REG_SM(-127, AR5K_PHY_AGCCOARSE_LO), AR5K_PHY_AGCCOARSE);

        ath5k_hw_reg_write(ah, (phy_sat & ~(AR5K_PHY_ADCSAT_ICNT |
                        AR5K_PHY_ADCSAT_THR)) |
                AR5K_REG_SM(2, AR5K_PHY_ADCSAT_ICNT) |
                AR5K_REG_SM(12, AR5K_PHY_ADCSAT_THR), AR5K_PHY_ADCSAT);

        udelay(20);

        AR5K_REG_ENABLE_BITS(ah, AR5K_PHY_AGC, AR5K_PHY_AGC_DISABLE);
        udelay(10);
        ath5k_hw_reg_write(ah, AR5K_PHY_RFSTG_DISABLE, AR5K_PHY_RFSTG);
        AR5K_REG_DISABLE_BITS(ah, AR5K_PHY_AGC, AR5K_PHY_AGC_DISABLE);

        usleep_range(1000, 1500);

        /*
         * Enable calibration and wait until completion
         */
        AR5K_REG_ENABLE_BITS(ah, AR5K_PHY_AGCCTL, AR5K_PHY_AGCCTL_CAL);

        ret = ath5k_hw_register_timeout(ah, AR5K_PHY_AGCCTL,
                        AR5K_PHY_AGCCTL_CAL, 0, false);

        /* Reset to normal state */
        ath5k_hw_reg_write(ah, phy_sig, AR5K_PHY_SIG);
        ath5k_hw_reg_write(ah, phy_agc, AR5K_PHY_AGCCOARSE);
        ath5k_hw_reg_write(ah, phy_sat, AR5K_PHY_ADCSAT);

        if (ret) {
                ATH5K_ERR(ah, "calibration timeout (%uMHz)\n",
                                channel->center_freq);
                return ret;
        }

        /*
         * Re-enable RX/TX and beacons
         */
        AR5K_REG_DISABLE_BITS(ah, AR5K_DIAG_SW_5210,
                AR5K_DIAG_SW_DIS_TX_5210 | AR5K_DIAG_SW_DIS_RX_5210);
        ath5k_hw_reg_write(ah, beacon, AR5K_BEACON_5210);

        return 0;
}

/**
 * ath5k_hw_rf511x_iq_calibrate() - Perform I/Q calibration on RF5111 and newer
 * @ah: The &struct ath5k_hw
 */
static int
ath5k_hw_rf511x_iq_calibrate(struct ath5k_hw *ah)
{
        u32 i_pwr, q_pwr;
        s32 iq_corr, i_coff, i_coffd, q_coff, q_coffd;
        int i;

        /* Skip if I/Q calibration is not needed or if it's still running */
        if (!ah->ah_iq_cal_needed)
                return -EINVAL;
        else if (ath5k_hw_reg_read(ah, AR5K_PHY_IQ) & AR5K_PHY_IQ_RUN) {
                ATH5K_DBG_UNLIMIT(ah, ATH5K_DEBUG_CALIBRATE,
                                "I/Q calibration still running");
                return -EBUSY;
        }

        /* Calibration has finished, get the results and re-run */

        /* Work around for empty results which can apparently happen on 5212:
         * Read registers up to 10 times until we get both i_pr and q_pwr */
        for (i = 0; i <= 10; i++) {
                iq_corr = ath5k_hw_reg_read(ah, AR5K_PHY_IQRES_CAL_CORR);
                i_pwr = ath5k_hw_reg_read(ah, AR5K_PHY_IQRES_CAL_PWR_I);
                q_pwr = ath5k_hw_reg_read(ah, AR5K_PHY_IQRES_CAL_PWR_Q);
                ATH5K_DBG_UNLIMIT(ah, ATH5K_DEBUG_CALIBRATE,
                        "iq_corr:%x i_pwr:%x q_pwr:%x", iq_corr, i_pwr, q_pwr);
                if (i_pwr && q_pwr)
                        break;
        }

        i_coffd = ((i_pwr >> 1) + (q_pwr >> 1)) >> 7;

        if (ah->ah_version == AR5K_AR5211)
                q_coffd = q_pwr >> 6;
        else
                q_coffd = q_pwr >> 7;

        /* In case i_coffd became zero, cancel calibration
         * not only it's too small, it'll also result a divide
         * by zero later on. */
        if (i_coffd == 0 || q_coffd < 2)
                return -ECANCELED;

        /* Protect against loss of sign bits */

        i_coff = (-iq_corr) / i_coffd;
        i_coff = clamp(i_coff, -32, 31); /* signed 6 bit */

        if (ah->ah_version == AR5K_AR5211)
                q_coff = (i_pwr / q_coffd) - 64;
        else
                q_coff = (i_pwr / q_coffd) - 128;
        q_coff = clamp(q_coff, -16, 15); /* signed 5 bit */

        ATH5K_DBG_UNLIMIT(ah, ATH5K_DEBUG_CALIBRATE,
                        "new I:%d Q:%d (i_coffd:%x q_coffd:%x)",
                        i_coff, q_coff, i_coffd, q_coffd);

        /* Commit new I/Q values (set enable bit last to match HAL sources) */
        AR5K_REG_WRITE_BITS(ah, AR5K_PHY_IQ, AR5K_PHY_IQ_CORR_Q_I_COFF, i_coff);
        AR5K_REG_WRITE_BITS(ah, AR5K_PHY_IQ, AR5K_PHY_IQ_CORR_Q_Q_COFF, q_coff);
        AR5K_REG_ENABLE_BITS(ah, AR5K_PHY_IQ, AR5K_PHY_IQ_CORR_ENABLE);

        /* Re-enable calibration -if we don't we'll commit
         * the same values again and again */
        AR5K_REG_WRITE_BITS(ah, AR5K_PHY_IQ,
                        AR5K_PHY_IQ_CAL_NUM_LOG_MAX, 15);
        AR5K_REG_ENABLE_BITS(ah, AR5K_PHY_IQ, AR5K_PHY_IQ_RUN);

        return 0;
}

/**
 * ath5k_hw_phy_calibrate() - Perform a PHY calibration
 * @ah: The &struct ath5k_hw
 * @channel: The &struct ieee80211_channel
 *
 * The main function we call from above to perform
 * a short or full PHY calibration based on RF chip
 * and current channel
 */
int
ath5k_hw_phy_calibrate(struct ath5k_hw *ah,
                struct ieee80211_channel *channel)
{
        int ret;

        if (ah->ah_radio == AR5K_RF5110)
                return ath5k_hw_rf5110_calibrate(ah, channel);

        ret = ath5k_hw_rf511x_iq_calibrate(ah);
        if (ret) {
                ATH5K_DBG_UNLIMIT(ah, ATH5K_DEBUG_CALIBRATE,
                        "No I/Q correction performed (%uMHz)\n",
                        channel->center_freq);

                /* Happens all the time if there is not much
                 * traffic, consider it normal behaviour. */
                ret = 0;
        }

        /* On full calibration request a PAPD probe for
         * gainf calibration if needed */
        if ((ah->ah_cal_mask & AR5K_CALIBRATION_FULL) &&
            (ah->ah_radio == AR5K_RF5111 ||
             ah->ah_radio == AR5K_RF5112) &&
            channel->hw_value != AR5K_MODE_11B)
                ath5k_hw_request_rfgain_probe(ah);

        /* Update noise floor */
        if (!(ah->ah_cal_mask & AR5K_CALIBRATION_NF))
                ath5k_hw_update_noise_floor(ah);

        return ret;
}


/***************************\
* Spur mitigation functions *
\***************************/

/**
 * ath5k_hw_set_spur_mitigation_filter() - Configure SPUR filter
 * @ah: The &struct ath5k_hw
 * @channel: The &struct ieee80211_channel
 *
 * This function gets called during PHY initialization to
 * configure the spur filter for the given channel. Spur is noise
 * generated due to "reflection" effects, for more information on this
 * method check out patent US7643810
 */
static void
ath5k_hw_set_spur_mitigation_filter(struct ath5k_hw *ah,
                                struct ieee80211_channel *channel)
{
        struct ath5k_eeprom_info *ee = &ah->ah_capabilities.cap_eeprom;
        u32 mag_mask[4] = {0, 0, 0, 0};
        u32 pilot_mask[2] = {0, 0};
        /* Note: fbin values are scaled up by 2 */
        u16 spur_chan_fbin, chan_fbin, symbol_width, spur_detection_window;
        s32 spur_delta_phase, spur_freq_sigma_delta;
        s32 spur_offset, num_symbols_x16;
        u8 num_symbol_offsets, i, freq_band;

        /* Convert current frequency to fbin value (the same way channels
         * are stored on EEPROM, check out ath5k_eeprom_bin2freq) and scale
         * up by 2 so we can compare it later */
        if (channel->band == NL80211_BAND_2GHZ) {
                chan_fbin = (channel->center_freq - 2300) * 10;
                freq_band = AR5K_EEPROM_BAND_2GHZ;
        } else {
                chan_fbin = (channel->center_freq - 4900) * 10;
                freq_band = AR5K_EEPROM_BAND_5GHZ;
        }

        /* Check if any spur_chan_fbin from EEPROM is
         * within our current channel's spur detection range */
        spur_chan_fbin = AR5K_EEPROM_NO_SPUR;
        spur_detection_window = AR5K_SPUR_CHAN_WIDTH;
        /* XXX: Half/Quarter channels ?*/
        if (ah->ah_bwmode == AR5K_BWMODE_40MHZ)
                spur_detection_window *= 2;

        for (i = 0; i < AR5K_EEPROM_N_SPUR_CHANS; i++) {
                spur_chan_fbin = ee->ee_spur_chans[i][freq_band];

                /* Note: mask cleans AR5K_EEPROM_NO_SPUR flag
                 * so it's zero if we got nothing from EEPROM */
                if (spur_chan_fbin == AR5K_EEPROM_NO_SPUR) {
                        spur_chan_fbin &= AR5K_EEPROM_SPUR_CHAN_MASK;
                        break;
                }

                if ((chan_fbin - spur_detection_window <=
                (spur_chan_fbin & AR5K_EEPROM_SPUR_CHAN_MASK)) &&
                (chan_fbin + spur_detection_window >=
                (spur_chan_fbin & AR5K_EEPROM_SPUR_CHAN_MASK))) {
                        spur_chan_fbin &= AR5K_EEPROM_SPUR_CHAN_MASK;
                        break;
                }
        }

        /* We need to enable spur filter for this channel */
        if (spur_chan_fbin) {
                spur_offset = spur_chan_fbin - chan_fbin;
                /*
                 * Calculate deltas:
                 * spur_freq_sigma_delta -> spur_offset / sample_freq << 21
                 * spur_delta_phase -> spur_offset / chip_freq << 11
                 * Note: Both values have 100Hz resolution
                 */
                switch (ah->ah_bwmode) {
                case AR5K_BWMODE_40MHZ:
                        /* Both sample_freq and chip_freq are 80MHz */
                        spur_delta_phase = (spur_offset << 16) / 25;
                        spur_freq_sigma_delta = (spur_delta_phase >> 10);
                        symbol_width = AR5K_SPUR_SYMBOL_WIDTH_BASE_100Hz * 2;
                        break;
                case AR5K_BWMODE_10MHZ:
                        /* Both sample_freq and chip_freq are 20MHz (?) */
                        spur_delta_phase = (spur_offset << 18) / 25;
                        spur_freq_sigma_delta = (spur_delta_phase >> 10);
                        symbol_width = AR5K_SPUR_SYMBOL_WIDTH_BASE_100Hz / 2;
                        break;
                case AR5K_BWMODE_5MHZ:
                        /* Both sample_freq and chip_freq are 10MHz (?) */
                        spur_delta_phase = (spur_offset << 19) / 25;
                        spur_freq_sigma_delta = (spur_delta_phase >> 10);
                        symbol_width = AR5K_SPUR_SYMBOL_WIDTH_BASE_100Hz / 4;
                        break;
                default:
                        if (channel->band == NL80211_BAND_5GHZ) {
                                /* Both sample_freq and chip_freq are 40MHz */
                                spur_delta_phase = (spur_offset << 17) / 25;
                                spur_freq_sigma_delta =
                                                (spur_delta_phase >> 10);
                                symbol_width =
                                        AR5K_SPUR_SYMBOL_WIDTH_BASE_100Hz;
                        } else {
                                /* sample_freq -> 40MHz chip_freq -> 44MHz
                                 * (for b compatibility) */
                                spur_delta_phase = (spur_offset << 17) / 25;
                                spur_freq_sigma_delta =
                                                (spur_offset << 8) / 55;
                                symbol_width =
                                        AR5K_SPUR_SYMBOL_WIDTH_BASE_100Hz;
                        }
                        break;
                }

                /* Calculate pilot and magnitude masks */

                /* Scale up spur_offset by 1000 to switch to 100HZ resolution
                 * and divide by symbol_width to find how many symbols we have
                 * Note: number of symbols is scaled up by 16 */
                num_symbols_x16 = ((spur_offset * 1000) << 4) / symbol_width;

                /* Spur is on a symbol if num_symbols_x16 % 16 is zero */
                if (!(num_symbols_x16 & 0xF))
                        /* _X_ */
                        num_symbol_offsets = 3;
                else
                        /* _xx_ */
                        num_symbol_offsets = 4;

                for (i = 0; i < num_symbol_offsets; i++) {

                        /* Calculate pilot mask */
                        s32 curr_sym_off =
                                (num_symbols_x16 / 16) + i + 25;

                        /* Pilot magnitude mask seems to be a way to
                         * declare the boundaries for our detection
                         * window or something, it's 2 for the middle
                         * value(s) where the symbol is expected to be
                         * and 1 on the boundary values */
                        u8 plt_mag_map =
                                (i == 0 || i == (num_symbol_offsets - 1))
                                                                ? 1 : 2;

                        if (curr_sym_off >= 0 && curr_sym_off <= 32) {
                                if (curr_sym_off <= 25)
                                        pilot_mask[0] |= 1 << curr_sym_off;
                                else if (curr_sym_off >= 27)
                                        pilot_mask[0] |= 1 << (curr_sym_off - 1);
                        } else if (curr_sym_off >= 33 && curr_sym_off <= 52)
                                pilot_mask[1] |= 1 << (curr_sym_off - 33);

                        /* Calculate magnitude mask (for viterbi decoder) */
                        if (curr_sym_off >= -1 && curr_sym_off <= 14)
                                mag_mask[0] |=
                                        plt_mag_map << (curr_sym_off + 1) * 2;
                        else if (curr_sym_off >= 15 && curr_sym_off <= 30)
                                mag_mask[1] |=
                                        plt_mag_map << (curr_sym_off - 15) * 2;
                        else if (curr_sym_off >= 31 && curr_sym_off <= 46)
                                mag_mask[2] |=
                                        plt_mag_map << (curr_sym_off - 31) * 2;
                        else if (curr_sym_off >= 47 && curr_sym_off <= 53)
                                mag_mask[3] |=
                                        plt_mag_map << (curr_sym_off - 47) * 2;

                }

                /* Write settings on hw to enable spur filter */
                AR5K_REG_WRITE_BITS(ah, AR5K_PHY_BIN_MASK_CTL,
                                        AR5K_PHY_BIN_MASK_CTL_RATE, 0xff);
                /* XXX: Self correlator also ? */
                AR5K_REG_ENABLE_BITS(ah, AR5K_PHY_IQ,
                                        AR5K_PHY_IQ_PILOT_MASK_EN |
                                        AR5K_PHY_IQ_CHAN_MASK_EN |
                                        AR5K_PHY_IQ_SPUR_FILT_EN);

                /* Set delta phase and freq sigma delta */
                ath5k_hw_reg_write(ah,
                                AR5K_REG_SM(spur_delta_phase,
                                        AR5K_PHY_TIMING_11_SPUR_DELTA_PHASE) |
                                AR5K_REG_SM(spur_freq_sigma_delta,
                                AR5K_PHY_TIMING_11_SPUR_FREQ_SD) |
                                AR5K_PHY_TIMING_11_USE_SPUR_IN_AGC,
                                AR5K_PHY_TIMING_11);

                /* Write pilot masks */
                ath5k_hw_reg_write(ah, pilot_mask[0], AR5K_PHY_TIMING_7);
                AR5K_REG_WRITE_BITS(ah, AR5K_PHY_TIMING_8,
                                        AR5K_PHY_TIMING_8_PILOT_MASK_2,
                                        pilot_mask[1]);

                ath5k_hw_reg_write(ah, pilot_mask[0], AR5K_PHY_TIMING_9);
                AR5K_REG_WRITE_BITS(ah, AR5K_PHY_TIMING_10,
                                        AR5K_PHY_TIMING_10_PILOT_MASK_2,
                                        pilot_mask[1]);

                /* Write magnitude masks */
                ath5k_hw_reg_write(ah, mag_mask[0], AR5K_PHY_BIN_MASK_1);
                ath5k_hw_reg_write(ah, mag_mask[1], AR5K_PHY_BIN_MASK_2);
                ath5k_hw_reg_write(ah, mag_mask[2], AR5K_PHY_BIN_MASK_3);
                AR5K_REG_WRITE_BITS(ah, AR5K_PHY_BIN_MASK_CTL,
                                        AR5K_PHY_BIN_MASK_CTL_MASK_4,
                                        mag_mask[3]);

                ath5k_hw_reg_write(ah, mag_mask[0], AR5K_PHY_BIN_MASK2_1);
                ath5k_hw_reg_write(ah, mag_mask[1], AR5K_PHY_BIN_MASK2_2);
                ath5k_hw_reg_write(ah, mag_mask[2], AR5K_PHY_BIN_MASK2_3);
                AR5K_REG_WRITE_BITS(ah, AR5K_PHY_BIN_MASK2_4,
                                        AR5K_PHY_BIN_MASK2_4_MASK_4,
                                        mag_mask[3]);

        } else if (ath5k_hw_reg_read(ah, AR5K_PHY_IQ) &
        AR5K_PHY_IQ_SPUR_FILT_EN) {
                /* Clean up spur mitigation settings and disable filter */
                AR5K_REG_WRITE_BITS(ah, AR5K_PHY_BIN_MASK_CTL,
                                        AR5K_PHY_BIN_MASK_CTL_RATE, 0);
                AR5K_REG_DISABLE_BITS(ah, AR5K_PHY_IQ,
                                        AR5K_PHY_IQ_PILOT_MASK_EN |
                                        AR5K_PHY_IQ_CHAN_MASK_EN |
                                        AR5K_PHY_IQ_SPUR_FILT_EN);
                ath5k_hw_reg_write(ah, 0, AR5K_PHY_TIMING_11);

                /* Clear pilot masks */
                ath5k_hw_reg_write(ah, 0, AR5K_PHY_TIMING_7);
                AR5K_REG_WRITE_BITS(ah, AR5K_PHY_TIMING_8,
                                        AR5K_PHY_TIMING_8_PILOT_MASK_2,
                                        0);

                ath5k_hw_reg_write(ah, 0, AR5K_PHY_TIMING_9);
                AR5K_REG_WRITE_BITS(ah, AR5K_PHY_TIMING_10,
                                        AR5K_PHY_TIMING_10_PILOT_MASK_2,
                                        0);

                /* Clear magnitude masks */
                ath5k_hw_reg_write(ah, 0, AR5K_PHY_BIN_MASK_1);
                ath5k_hw_reg_write(ah, 0, AR5K_PHY_BIN_MASK_2);
                ath5k_hw_reg_write(ah, 0, AR5K_PHY_BIN_MASK_3);
                AR5K_REG_WRITE_BITS(ah, AR5K_PHY_BIN_MASK_CTL,
                                        AR5K_PHY_BIN_MASK_CTL_MASK_4,
                                        0);

                ath5k_hw_reg_write(ah, 0, AR5K_PHY_BIN_MASK2_1);
                ath5k_hw_reg_write(ah, 0, AR5K_PHY_BIN_MASK2_2);
                ath5k_hw_reg_write(ah, 0, AR5K_PHY_BIN_MASK2_3);
                AR5K_REG_WRITE_BITS(ah, AR5K_PHY_BIN_MASK2_4,
                                        AR5K_PHY_BIN_MASK2_4_MASK_4,
                                        0);
        }
}


/*****************\
* Antenna control *
\*****************/

/**
 * DOC: Antenna control
 *
 * Hw supports up to 14 antennas ! I haven't found any card that implements
 * that. The maximum number of antennas I've seen is up to 4 (2 for 2GHz and 2
 * for 5GHz). Antenna 1 (MAIN) should be omnidirectional, 2 (AUX)
 * omnidirectional or sectorial and antennas 3-14 sectorial (or directional).
 *
 * We can have a single antenna for RX and multiple antennas for TX.
 * RX antenna is our "default" antenna (usually antenna 1) set on
 * DEFAULT_ANTENNA register and TX antenna is set on each TX control descriptor
 * (0 for automatic selection, 1 - 14 antenna number).
 *
 * We can let hw do all the work doing fast antenna diversity for both
 * tx and rx or we can do things manually. Here are the options we have
 * (all are bits of STA_ID1 register):
 *
 * AR5K_STA_ID1_DEFAULT_ANTENNA -> When 0 is set as the TX antenna on TX
 * control descriptor, use the default antenna to transmit or else use the last
 * antenna on which we received an ACK.
 *
 * AR5K_STA_ID1_DESC_ANTENNA -> Update default antenna after each TX frame to
 * the antenna on which we got the ACK for that frame.
 *
 * AR5K_STA_ID1_RTS_DEF_ANTENNA -> Use default antenna for RTS or else use the
 * one on the TX descriptor.
 *
 * AR5K_STA_ID1_SELFGEN_DEF_ANT -> Use default antenna for self generated frames
 * (ACKs etc), or else use current antenna (the one we just used for TX).
 *
 * Using the above we support the following scenarios:
 *
 * AR5K_ANTMODE_DEFAULT -> Hw handles antenna diversity etc automatically
 *
 * AR5K_ANTMODE_FIXED_A -> Only antenna A (MAIN) is present
 *
 * AR5K_ANTMODE_FIXED_B -> Only antenna B (AUX) is present
 *
 * AR5K_ANTMODE_SINGLE_AP -> Sta locked on a single ap
 *
 * AR5K_ANTMODE_SECTOR_AP -> AP with tx antenna set on tx desc
 *
 * AR5K_ANTMODE_SECTOR_STA -> STA with tx antenna set on tx desc
 *
 * AR5K_ANTMODE_DEBUG Debug mode -A -> Rx, B-> Tx-
 *
 * Also note that when setting antenna to F on tx descriptor card inverts
 * current tx antenna.
 */

/**
 * ath5k_hw_set_def_antenna() - Set default rx antenna on AR5211/5212 and newer
 * @ah: The &struct ath5k_hw
 * @ant: Antenna number
 */
static void
ath5k_hw_set_def_antenna(struct ath5k_hw *ah, u8 ant)
{
        if (ah->ah_version != AR5K_AR5210)
                ath5k_hw_reg_write(ah, ant & 0x7, AR5K_DEFAULT_ANTENNA);
}

/**
 * ath5k_hw_set_fast_div() -  Enable/disable fast rx antenna diversity
 * @ah: The &struct ath5k_hw
 * @ee_mode: One of enum ath5k_driver_mode
 * @enable: True to enable, false to disable
 */
static void
ath5k_hw_set_fast_div(struct ath5k_hw *ah, u8 ee_mode, bool enable)
{
        switch (ee_mode) {
        case AR5K_EEPROM_MODE_11G:
                /* XXX: This is set to
                 * disabled on initvals !!! */
        case AR5K_EEPROM_MODE_11A:
                if (enable)
                        AR5K_REG_DISABLE_BITS(ah, AR5K_PHY_AGCCTL,
                                        AR5K_PHY_AGCCTL_OFDM_DIV_DIS);
                else
                        AR5K_REG_ENABLE_BITS(ah, AR5K_PHY_AGCCTL,
                                        AR5K_PHY_AGCCTL_OFDM_DIV_DIS);
                break;
        case AR5K_EEPROM_MODE_11B:
                AR5K_REG_ENABLE_BITS(ah, AR5K_PHY_AGCCTL,
                                        AR5K_PHY_AGCCTL_OFDM_DIV_DIS);
                break;
        default:
                return;
        }

        if (enable) {
                AR5K_REG_WRITE_BITS(ah, AR5K_PHY_RESTART,
                                AR5K_PHY_RESTART_DIV_GC, 4);

                AR5K_REG_ENABLE_BITS(ah, AR5K_PHY_FAST_ANT_DIV,
                                        AR5K_PHY_FAST_ANT_DIV_EN);
        } else {
                AR5K_REG_WRITE_BITS(ah, AR5K_PHY_RESTART,
                                AR5K_PHY_RESTART_DIV_GC, 0);

                AR5K_REG_DISABLE_BITS(ah, AR5K_PHY_FAST_ANT_DIV,
                                        AR5K_PHY_FAST_ANT_DIV_EN);
        }
}

/**
 * ath5k_hw_set_antenna_switch() - Set up antenna switch table
 * @ah: The &struct ath5k_hw
 * @ee_mode: One of enum ath5k_driver_mode
 *
 * Switch table comes from EEPROM and includes information on controlling
 * the 2 antenna RX attenuators
 */
void
ath5k_hw_set_antenna_switch(struct ath5k_hw *ah, u8 ee_mode)
{
        u8 ant0, ant1;

        /*
         * In case a fixed antenna was set as default
         * use the same switch table twice.
         */
        if (ah->ah_ant_mode == AR5K_ANTMODE_FIXED_A)
                ant0 = ant1 = AR5K_ANT_SWTABLE_A;
        else if (ah->ah_ant_mode == AR5K_ANTMODE_FIXED_B)
                ant0 = ant1 = AR5K_ANT_SWTABLE_B;
        else {
                ant0 = AR5K_ANT_SWTABLE_A;
                ant1 = AR5K_ANT_SWTABLE_B;
        }

        /* Set antenna idle switch table */
        AR5K_REG_WRITE_BITS(ah, AR5K_PHY_ANT_CTL,
                        AR5K_PHY_ANT_CTL_SWTABLE_IDLE,
                        (ah->ah_ant_ctl[ee_mode][AR5K_ANT_CTL] |
                        AR5K_PHY_ANT_CTL_TXRX_EN));

        /* Set antenna switch tables */
        ath5k_hw_reg_write(ah, ah->ah_ant_ctl[ee_mode][ant0],
                AR5K_PHY_ANT_SWITCH_TABLE_0);
        ath5k_hw_reg_write(ah, ah->ah_ant_ctl[ee_mode][ant1],
                AR5K_PHY_ANT_SWITCH_TABLE_1);
}

/**
 * ath5k_hw_set_antenna_mode() -  Set antenna operating mode
 * @ah: The &struct ath5k_hw
 * @ant_mode: One of enum ath5k_ant_mode
 */
void
ath5k_hw_set_antenna_mode(struct ath5k_hw *ah, u8 ant_mode)
{
        struct ieee80211_channel *channel = ah->ah_current_channel;
        bool use_def_for_tx, update_def_on_tx, use_def_for_rts, fast_div;
        bool use_def_for_sg;
        int ee_mode;
        u8 def_ant, tx_ant;
        u32 sta_id1 = 0;

        /* if channel is not initialized yet we can't set the antennas
         * so just store the mode. it will be set on the next reset */
        if (channel == NULL) {
                ah->ah_ant_mode = ant_mode;
                return;
        }

        def_ant = ah->ah_def_ant;

        ee_mode = ath5k_eeprom_mode_from_channel(ah, channel);

        switch (ant_mode) {
        case AR5K_ANTMODE_DEFAULT:
                tx_ant = 0;
                use_def_for_tx = false;
                update_def_on_tx = false;
                use_def_for_rts = false;
                use_def_for_sg = false;
                fast_div = true;
                break;
        case AR5K_ANTMODE_FIXED_A:
                def_ant = 1;
                tx_ant = 1;
                use_def_for_tx = true;
                update_def_on_tx = false;
                use_def_for_rts = true;
                use_def_for_sg = true;
                fast_div = false;
                break;
        case AR5K_ANTMODE_FIXED_B:
                def_ant = 2;
                tx_ant = 2;
                use_def_for_tx = true;
                update_def_on_tx = false;
                use_def_for_rts = true;
                use_def_for_sg = true;
                fast_div = false;
                break;
        case AR5K_ANTMODE_SINGLE_AP:
                def_ant = 1;    /* updated on tx */
                tx_ant = 0;
                use_def_for_tx = true;
                update_def_on_tx = true;
                use_def_for_rts = true;
                use_def_for_sg = true;
                fast_div = true;
                break;
        case AR5K_ANTMODE_SECTOR_AP:
                tx_ant = 1;     /* variable */
                use_def_for_tx = false;
                update_def_on_tx = false;
                use_def_for_rts = true;
                use_def_for_sg = false;
                fast_div = false;
                break;
        case AR5K_ANTMODE_SECTOR_STA:
                tx_ant = 1;     /* variable */
                use_def_for_tx = true;
                update_def_on_tx = false;
                use_def_for_rts = true;
                use_def_for_sg = false;
                fast_div = true;
                break;
        case AR5K_ANTMODE_DEBUG:
                def_ant = 1;
                tx_ant = 2;
                use_def_for_tx = false;
                update_def_on_tx = false;
                use_def_for_rts = false;
                use_def_for_sg = false;
                fast_div = false;
                break;
        default:
                return;
        }

        ah->ah_tx_ant = tx_ant;
        ah->ah_ant_mode = ant_mode;
        ah->ah_def_ant = def_ant;

        sta_id1 |= use_def_for_tx ? AR5K_STA_ID1_DEFAULT_ANTENNA : 0;
        sta_id1 |= update_def_on_tx ? AR5K_STA_ID1_DESC_ANTENNA : 0;
        sta_id1 |= use_def_for_rts ? AR5K_STA_ID1_RTS_DEF_ANTENNA : 0;
        sta_id1 |= use_def_for_sg ? AR5K_STA_ID1_SELFGEN_DEF_ANT : 0;

        AR5K_REG_DISABLE_BITS(ah, AR5K_STA_ID1, AR5K_STA_ID1_ANTENNA_SETTINGS);

        if (sta_id1)
                AR5K_REG_ENABLE_BITS(ah, AR5K_STA_ID1, sta_id1);

        ath5k_hw_set_antenna_switch(ah, ee_mode);
        /* Note: set diversity before default antenna
         * because it won't work correctly */
        ath5k_hw_set_fast_div(ah, ee_mode, fast_div);
        ath5k_hw_set_def_antenna(ah, def_ant);
}


/****************\
* TX power setup *
\****************/

/*
 * Helper functions
 */

/**
 * ath5k_get_interpolated_value() - Get interpolated Y val between two points
 * @target: X value of the middle point
 * @x_left: X value of the left point
 * @x_right: X value of the right point
 * @y_left: Y value of the left point
 * @y_right: Y value of the right point
 */
static s16
ath5k_get_interpolated_value(s16 target, s16 x_left, s16 x_right,
                                        s16 y_left, s16 y_right)
{
        s16 ratio, result;

        /* Avoid divide by zero and skip interpolation
         * if we have the same point */
        if ((x_left == x_right) || (y_left == y_right))
                return y_left;

        /*
         * Since we use ints and not fps, we need to scale up in
         * order to get a sane ratio value (or else we 'll eg. get
         * always 1 instead of 1.25, 1.75 etc). We scale up by 100
         * to have some accuracy both for 0.5 and 0.25 steps.
         */
        ratio = ((100 * y_right - 100 * y_left) / (x_right - x_left));

        /* Now scale down to be in range */
        result = y_left + (ratio * (target - x_left) / 100);

        return result;
}

/**
 * ath5k_get_linear_pcdac_min() - Find vertical boundary (min pwr) for the
 * linear PCDAC curve
 * @stepL: Left array with y values (pcdac steps)
 * @stepR: Right array with y values (pcdac steps)
 * @pwrL: Left array with x values (power steps)
 * @pwrR: Right array with x values (power steps)
 *
 * Since we have the top of the curve and we draw the line below
 * until we reach 1 (1 pcdac step) we need to know which point
 * (x value) that is so that we don't go below x axis and have negative
 * pcdac values when creating the curve, or fill the table with zeros.
 */
static s16
ath5k_get_linear_pcdac_min(const u8 *stepL, const u8 *stepR,
                                const s16 *pwrL, const s16 *pwrR)
{
        s8 tmp;
        s16 min_pwrL, min_pwrR;
        s16 pwr_i;

        /* Some vendors write the same pcdac value twice !!! */
        if (stepL[0] == stepL[1] || stepR[0] == stepR[1])
                return max(pwrL[0], pwrR[0]);

        if (pwrL[0] == pwrL[1])
                min_pwrL = pwrL[0];
        else {
                pwr_i = pwrL[0];
                do {
                        pwr_i--;
                        tmp = (s8) ath5k_get_interpolated_value(pwr_i,
                                                        pwrL[0], pwrL[1],
                                                        stepL[0], stepL[1]);
                } while (tmp > 1);

                min_pwrL = pwr_i;
        }

        if (pwrR[0] == pwrR[1])
                min_pwrR = pwrR[0];
        else {
                pwr_i = pwrR[0];
                do {
                        pwr_i--;
                        tmp = (s8) ath5k_get_interpolated_value(pwr_i,
                                                        pwrR[0], pwrR[1],
                                                        stepR[0], stepR[1]);
                } while (tmp > 1);

                min_pwrR = pwr_i;
        }

        /* Keep the right boundary so that it works for both curves */
        return max(min_pwrL, min_pwrR);
}

/**
 * ath5k_create_power_curve() - Create a Power to PDADC or PCDAC curve
 * @pmin: Minimum power value (xmin)
 * @pmax: Maximum power value (xmax)
 * @pwr: Array of power steps (x values)
 * @vpd: Array of matching PCDAC/PDADC steps (y values)
 * @num_points: Number of provided points
 * @vpd_table: Array to fill with the full PCDAC/PDADC values (y values)
 * @type: One of enum ath5k_powertable_type (eeprom.h)
 *
 * Interpolate (pwr,vpd) points to create a Power to PDADC or a
 * Power to PCDAC curve.
 *
 * Each curve has power on x axis (in 0.5dB units) and PCDAC/PDADC
 * steps (offsets) on y axis. Power can go up to 31.5dB and max
 * PCDAC/PDADC step for each curve is 64 but we can write more than
 * one curves on hw so we can go up to 128 (which is the max step we
 * can write on the final table).
 *
 * We write y values (PCDAC/PDADC steps) on hw.
 */
static void
ath5k_create_power_curve(s16 pmin, s16 pmax,
                        const s16 *pwr, const u8 *vpd,
                        u8 num_points,
                        u8 *vpd_table, u8 type)
{
        u8 idx[2] = { 0, 1 };
        s16 pwr_i = 2 * pmin;
        int i;

        if (num_points < 2)
                return;

        /* We want the whole line, so adjust boundaries
         * to cover the entire power range. Note that
         * power values are already 0.25dB so no need
         * to multiply pwr_i by 2 */
        if (type == AR5K_PWRTABLE_LINEAR_PCDAC) {
                pwr_i = pmin;
                pmin = 0;
                pmax = 63;
        }

        /* Find surrounding turning points (TPs)
         * and interpolate between them */
        for (i = 0; (i <= (u16) (pmax - pmin)) &&
        (i < AR5K_EEPROM_POWER_TABLE_SIZE); i++) {

                /* We passed the right TP, move to the next set of TPs
                 * if we pass the last TP, extrapolate above using the last
                 * two TPs for ratio */
                if ((pwr_i > pwr[idx[1]]) && (idx[1] < num_points - 1)) {
                        idx[0]++;
                        idx[1]++;
                }

                vpd_table[i] = (u8) ath5k_get_interpolated_value(pwr_i,
                                                pwr[idx[0]], pwr[idx[1]],
                                                vpd[idx[0]], vpd[idx[1]]);

                /* Increase by 0.5dB
                 * (0.25 dB units) */
                pwr_i += 2;
        }
}

/**
 * ath5k_get_chan_pcal_surrounding_piers() - Get surrounding calibration piers
 * for a given channel.
 * @ah: The &struct ath5k_hw
 * @channel: The &struct ieee80211_channel
 * @pcinfo_l: The &struct ath5k_chan_pcal_info to put the left cal. pier
 * @pcinfo_r: The &struct ath5k_chan_pcal_info to put the right cal. pier
 *
 * Get the surrounding per-channel power calibration piers
 * for a given frequency so that we can interpolate between
 * them and come up with an appropriate dataset for our current
 * channel.
 */
static void
ath5k_get_chan_pcal_surrounding_piers(struct ath5k_hw *ah,
                        struct ieee80211_channel *channel,
                        struct ath5k_chan_pcal_info **pcinfo_l,
                        struct ath5k_chan_pcal_info **pcinfo_r)
{
        struct ath5k_eeprom_info *ee = &ah->ah_capabilities.cap_eeprom;
        struct ath5k_chan_pcal_info *pcinfo;
        u8 idx_l, idx_r;
        u8 mode, max, i;
        u32 target = channel->center_freq;

        idx_l = 0;
        idx_r = 0;

        switch (channel->hw_value) {
        case AR5K_EEPROM_MODE_11A:
                pcinfo = ee->ee_pwr_cal_a;
                mode = AR5K_EEPROM_MODE_11A;
                break;
        case AR5K_EEPROM_MODE_11B:
                pcinfo = ee->ee_pwr_cal_b;
                mode = AR5K_EEPROM_MODE_11B;
                break;
        case AR5K_EEPROM_MODE_11G:
        default:
                pcinfo = ee->ee_pwr_cal_g;
                mode = AR5K_EEPROM_MODE_11G;
                break;
        }
        max = ee->ee_n_piers[mode] - 1;

        /* Frequency is below our calibrated
         * range. Use the lowest power curve
         * we have */
        if (target < pcinfo[0].freq) {
                idx_l = idx_r = 0;
                goto done;
        }

        /* Frequency is above our calibrated
         * range. Use the highest power curve
         * we have */
        if (target > pcinfo[max].freq) {
                idx_l = idx_r = max;
                goto done;
        }

        /* Frequency is inside our calibrated
         * channel range. Pick the surrounding
         * calibration piers so that we can
         * interpolate */
        for (i = 0; i <= max; i++) {

                /* Frequency matches one of our calibration
                 * piers, no need to interpolate, just use
                 * that calibration pier */
                if (pcinfo[i].freq == target) {
                        idx_l = idx_r = i;
                        goto done;
                }

                /* We found a calibration pier that's above
                 * frequency, use this pier and the previous
                 * one to interpolate */
                if (target < pcinfo[i].freq) {
                        idx_r = i;
                        idx_l = idx_r - 1;
                        goto done;
                }
        }

done:
        *pcinfo_l = &pcinfo[idx_l];
        *pcinfo_r = &pcinfo[idx_r];
}

/**
 * ath5k_get_rate_pcal_data() - Get the interpolated per-rate power
 * calibration data
 * @ah: The &struct ath5k_hw *ah,
 * @channel: The &struct ieee80211_channel
 * @rates: The &struct ath5k_rate_pcal_info to fill
 *
 * Get the surrounding per-rate power calibration data
 * for a given frequency and interpolate between power
 * values to set max target power supported by hw for
 * each rate on this frequency.
 */
static void
ath5k_get_rate_pcal_data(struct ath5k_hw *ah,
                        struct ieee80211_channel *channel,
                        struct ath5k_rate_pcal_info *rates)
{
        struct ath5k_eeprom_info *ee = &ah->ah_capabilities.cap_eeprom;
        struct ath5k_rate_pcal_info *rpinfo;
        u8 idx_l, idx_r;
        u8 mode, max, i;
        u32 target = channel->center_freq;

        idx_l = 0;
        idx_r = 0;

        switch (channel->hw_value) {
        case AR5K_MODE_11A:
                rpinfo = ee->ee_rate_tpwr_a;
                mode = AR5K_EEPROM_MODE_11A;
                break;
        case AR5K_MODE_11B:
                rpinfo = ee->ee_rate_tpwr_b;
                mode = AR5K_EEPROM_MODE_11B;
                break;
        case AR5K_MODE_11G:
        default:
                rpinfo = ee->ee_rate_tpwr_g;
                mode = AR5K_EEPROM_MODE_11G;
                break;
        }
        max = ee->ee_rate_target_pwr_num[mode] - 1;

        /* Get the surrounding calibration
         * piers - same as above */
        if (target < rpinfo[0].freq) {
                idx_l = idx_r = 0;
                goto done;
        }

        if (target > rpinfo[max].freq) {
                idx_l = idx_r = max;
                goto done;
        }

        for (i = 0; i <= max; i++) {

                if (rpinfo[i].freq == target) {
                        idx_l = idx_r = i;
                        goto done;
                }

                if (target < rpinfo[i].freq) {
                        idx_r = i;
                        idx_l = idx_r - 1;
                        goto done;
                }
        }

done:
        /* Now interpolate power value, based on the frequency */
        rates->freq = target;

        rates->target_power_6to24 =
                ath5k_get_interpolated_value(target, rpinfo[idx_l].freq,
                                        rpinfo[idx_r].freq,
                                        rpinfo[idx_l].target_power_6to24,
                                        rpinfo[idx_r].target_power_6to24);

        rates->target_power_36 =
                ath5k_get_interpolated_value(target, rpinfo[idx_l].freq,
                                        rpinfo[idx_r].freq,
                                        rpinfo[idx_l].target_power_36,
                                        rpinfo[idx_r].target_power_36);

        rates->target_power_48 =
                ath5k_get_interpolated_value(target, rpinfo[idx_l].freq,
                                        rpinfo[idx_r].freq,
                                        rpinfo[idx_l].target_power_48,
                                        rpinfo[idx_r].target_power_48);

        rates->target_power_54 =
                ath5k_get_interpolated_value(target, rpinfo[idx_l].freq,
                                        rpinfo[idx_r].freq,
                                        rpinfo[idx_l].target_power_54,
                                        rpinfo[idx_r].target_power_54);
}

/**
 * ath5k_get_max_ctl_power() - Get max edge power for a given frequency
 * @ah: the &struct ath5k_hw
 * @channel: The &struct ieee80211_channel
 *
 * Get the max edge power for this channel if
 * we have such data from EEPROM's Conformance Test
 * Limits (CTL), and limit max power if needed.
 */
static void
ath5k_get_max_ctl_power(struct ath5k_hw *ah,
                        struct ieee80211_channel *channel)
{
        struct ath_regulatory *regulatory = ath5k_hw_regulatory(ah);
        struct ath5k_eeprom_info *ee = &ah->ah_capabilities.cap_eeprom;
        struct ath5k_edge_power *rep = ee->ee_ctl_pwr;
        u8 *ctl_val = ee->ee_ctl;
        s16 max_chan_pwr = ah->ah_txpower.txp_max_pwr / 4;
        s16 edge_pwr = 0;
        u8 rep_idx;
        u8 i, ctl_mode;
        u8 ctl_idx = 0xFF;
        u32 target = channel->center_freq;

        ctl_mode = ath_regd_get_band_ctl(regulatory, channel->band);

        switch (channel->hw_value) {
        case AR5K_MODE_11A:
                if (ah->ah_bwmode == AR5K_BWMODE_40MHZ)
                        ctl_mode |= AR5K_CTL_TURBO;
                else
                        ctl_mode |= AR5K_CTL_11A;
                break;
        case AR5K_MODE_11G:
                if (ah->ah_bwmode == AR5K_BWMODE_40MHZ)
                        ctl_mode |= AR5K_CTL_TURBOG;
                else
                        ctl_mode |= AR5K_CTL_11G;
                break;
        case AR5K_MODE_11B:
                ctl_mode |= AR5K_CTL_11B;
                break;
        default:
                return;
        }

        for (i = 0; i < ee->ee_ctls; i++) {
                if (ctl_val[i] == ctl_mode) {
                        ctl_idx = i;
                        break;
                }
        }

        /* If we have a CTL dataset available grab it and find the
         * edge power for our frequency */
        if (ctl_idx == 0xFF)
                return;

        /* Edge powers are sorted by frequency from lower
         * to higher. Each CTL corresponds to 8 edge power
         * measurements. */
        rep_idx = ctl_idx * AR5K_EEPROM_N_EDGES;

        /* Don't do boundaries check because we
         * might have more that one bands defined
         * for this mode */

        /* Get the edge power that's closer to our
         * frequency */
        for (i = 0; i < AR5K_EEPROM_N_EDGES; i++) {
                rep_idx += i;
                if (target <= rep[rep_idx].freq)
                        edge_pwr = (s16) rep[rep_idx].edge;
        }

        if (edge_pwr)
                ah->ah_txpower.txp_max_pwr = 4 * min(edge_pwr, max_chan_pwr);
}


/*
 * Power to PCDAC table functions
 */

/**
 * DOC: Power to PCDAC table functions
 *
 * For RF5111 we have an XPD -eXternal Power Detector- curve
 * for each calibrated channel. Each curve has 0,5dB Power steps
 * on x axis and PCDAC steps (offsets) on y axis and looks like an
 * exponential function. To recreate the curve we read 11 points
 * from eeprom (eeprom.c) and interpolate here.
 *
 * For RF5112 we have 4 XPD -eXternal Power Detector- curves
 * for each calibrated channel on 0, -6, -12 and -18dBm but we only
 * use the higher (3) and the lower (0) curves. Each curve again has 0.5dB
 * power steps on x axis and PCDAC steps on y axis and looks like a
 * linear function. To recreate the curve and pass the power values
 * on hw, we get 4 points for xpd 0 (lower gain -> max power)
 * and 3 points for xpd 3 (higher gain -> lower power) from eeprom (eeprom.c)
 * and interpolate here.
 *
 * For a given channel we get the calibrated points (piers) for it or
 * -if we don't have calibration data for this specific channel- from the
 * available surrounding channels we have calibration data for, after we do a
 * linear interpolation between them. Then since we have our calibrated points
 * for this channel, we do again a linear interpolation between them to get the
 * whole curve.
 *
 * We finally write the Y values of the curve(s) (the PCDAC values) on hw
 */

/**
 * ath5k_fill_pwr_to_pcdac_table() - Fill Power to PCDAC table on RF5111
 * @ah: The &struct ath5k_hw
 * @table_min: Minimum power (x min)
 * @table_max: Maximum power (x max)
 *
 * No further processing is needed for RF5111, the only thing we have to
 * do is fill the values below and above calibration range since eeprom data
 * may not cover the entire PCDAC table.
 */
static void
ath5k_fill_pwr_to_pcdac_table(struct ath5k_hw *ah, s16* table_min,
                                                        s16 *table_max)
{
        u8      *pcdac_out = ah->ah_txpower.txp_pd_table;
        u8      *pcdac_tmp = ah->ah_txpower.tmpL[0];
        u8      pcdac_0, pcdac_n, pcdac_i, pwr_idx, i;
        s16     min_pwr, max_pwr;

        /* Get table boundaries */
        min_pwr = table_min[0];
        pcdac_0 = pcdac_tmp[0];

        max_pwr = table_max[0];
        pcdac_n = pcdac_tmp[table_max[0] - table_min[0]];

        /* Extrapolate below minimum using pcdac_0 */
        pcdac_i = 0;
        for (i = 0; i < min_pwr; i++)
                pcdac_out[pcdac_i++] = pcdac_0;

        /* Copy values from pcdac_tmp */
        pwr_idx = min_pwr;
        for (i = 0; pwr_idx <= max_pwr &&
                    pcdac_i < AR5K_EEPROM_POWER_TABLE_SIZE; i++) {
                pcdac_out[pcdac_i++] = pcdac_tmp[i];
                pwr_idx++;
        }

        /* Extrapolate above maximum */
        while (pcdac_i < AR5K_EEPROM_POWER_TABLE_SIZE)
                pcdac_out[pcdac_i++] = pcdac_n;

}

/**
 * ath5k_combine_linear_pcdac_curves() - Combine available PCDAC Curves
 * @ah: The &struct ath5k_hw
 * @table_min: Minimum power (x min)
 * @table_max: Maximum power (x max)
 * @pdcurves: Number of pd curves
 *
 * Combine available XPD Curves and fill Linear Power to PCDAC table on RF5112
 * RFX112 can have up to 2 curves (one for low txpower range and one for
 * higher txpower range). We need to put them both on pcdac_out and place
 * them in the correct location. In case we only have one curve available
 * just fit it on pcdac_out (it's supposed to cover the entire range of
 * available pwr levels since it's always the higher power curve). Extrapolate
 * below and above final table if needed.
 */
static void
ath5k_combine_linear_pcdac_curves(struct ath5k_hw *ah, s16* table_min,
                                                s16 *table_max, u8 pdcurves)
{
        u8      *pcdac_out = ah->ah_txpower.txp_pd_table;
        u8      *pcdac_low_pwr;
        u8      *pcdac_high_pwr;
        u8      *pcdac_tmp;
        u8      pwr;
        s16     max_pwr_idx;
        s16     min_pwr_idx;
        s16     mid_pwr_idx = 0;
        /* Edge flag turns on the 7nth bit on the PCDAC
         * to declare the higher power curve (force values
         * to be greater than 64). If we only have one curve
         * we don't need to set this, if we have 2 curves and
         * fill the table backwards this can also be used to
         * switch from higher power curve to lower power curve */
        u8      edge_flag;
        int     i;

        /* When we have only one curve available
         * that's the higher power curve. If we have
         * two curves the first is the high power curve
         * and the next is the low power curve. */
        if (pdcurves > 1) {
                pcdac_low_pwr = ah->ah_txpower.tmpL[1];
                pcdac_high_pwr = ah->ah_txpower.tmpL[0];
                mid_pwr_idx = table_max[1] - table_min[1] - 1;
                max_pwr_idx = (table_max[0] - table_min[0]) / 2;

                /* If table size goes beyond 31.5dB, keep the
                 * upper 31.5dB range when setting tx power.
                 * Note: 126 = 31.5 dB in quarter dB steps */
                if (table_max[0] - table_min[1] > 126)
                        min_pwr_idx = table_max[0] - 126;
                else
                        min_pwr_idx = table_min[1];

                /* Since we fill table backwards
                 * start from high power curve */
                pcdac_tmp = pcdac_high_pwr;

                edge_flag = 0x40;
        } else {
                pcdac_low_pwr = ah->ah_txpower.tmpL[1]; /* Zeroed */
                pcdac_high_pwr = ah->ah_txpower.tmpL[0];
                min_pwr_idx = table_min[0];
                max_pwr_idx = (table_max[0] - table_min[0]) / 2;
                pcdac_tmp = pcdac_high_pwr;
                edge_flag = 0;
        }

        /* This is used when setting tx power*/
        ah->ah_txpower.txp_min_idx = min_pwr_idx / 2;

        /* Fill Power to PCDAC table backwards */
        pwr = max_pwr_idx;
        for (i = 63; i >= 0; i--) {
                /* Entering lower power range, reset
                 * edge flag and set pcdac_tmp to lower
                 * power curve.*/
                if (edge_flag == 0x40 &&
                (2 * pwr <= (table_max[1] - table_min[0]) || pwr == 0)) {
                        edge_flag = 0x00;
                        pcdac_tmp = pcdac_low_pwr;
                        pwr = mid_pwr_idx / 2;
                }

                /* Don't go below 1, extrapolate below if we have
                 * already switched to the lower power curve -or
                 * we only have one curve and edge_flag is zero
                 * anyway */
                if (pcdac_tmp[pwr] < 1 && (edge_flag == 0x00)) {
                        while (i >= 0) {

                                pcdac_out[i] = pcdac_out[i + 1];
                                i--;
                        }
                        break;
                }

                pcdac_out[i] = pcdac_tmp[pwr] | edge_flag;

                /* Extrapolate above if pcdac is greater than
                 * 126 -this can happen because we OR pcdac_out
                 * value with edge_flag on high power curve */
                if (pcdac_out[i] > 126)
                        pcdac_out[i] = 126;

                /* Decrease by a 0.5dB step */
                pwr--;
        }
}

/**
 * ath5k_write_pcdac_table() - Write the PCDAC values on hw
 * @ah: The &struct ath5k_hw
 */
static void
ath5k_write_pcdac_table(struct ath5k_hw *ah)
{
        u8      *pcdac_out = ah->ah_txpower.txp_pd_table;
        int     i;

        /*
         * Write TX power values
         */
        for (i = 0; i < (AR5K_EEPROM_POWER_TABLE_SIZE / 2); i++) {
                ath5k_hw_reg_write(ah,
                        (((pcdac_out[2 * i + 0] << 8 | 0xff) & 0xffff) << 0) |
                        (((pcdac_out[2 * i + 1] << 8 | 0xff) & 0xffff) << 16),
                        AR5K_PHY_PCDAC_TXPOWER(i));
        }
}


/*
 * Power to PDADC table functions
 */

/**
 * DOC: Power to PDADC table functions
 *
 * For RF2413 and later we have a Power to PDADC table (Power Detector)
 * instead of a PCDAC (Power Control) and 4 pd gain curves for each
 * calibrated channel. Each curve has power on x axis in 0.5 db steps and
 * PDADC steps on y axis and looks like an exponential function like the
 * RF5111 curve.
 *
 * To recreate the curves we read the points from eeprom (eeprom.c)
 * and interpolate here. Note that in most cases only 2 (higher and lower)
 * curves are used (like RF5112) but vendors have the opportunity to include
 * all 4 curves on eeprom. The final curve (higher power) has an extra
 * point for better accuracy like RF5112.
 *
 * The process is similar to what we do above for RF5111/5112
 */

/**
 * ath5k_combine_pwr_to_pdadc_curves() - Combine the various PDADC curves
 * @ah: The &struct ath5k_hw
 * @pwr_min: Minimum power (x min)
 * @pwr_max: Maximum power (x max)
 * @pdcurves: Number of available curves
 *
 * Combine the various pd curves and create the final Power to PDADC table
 * We can have up to 4 pd curves, we need to do a similar process
 * as we do for RF5112. This time we don't have an edge_flag but we
 * set the gain boundaries on a separate register.
 */
static void
ath5k_combine_pwr_to_pdadc_curves(struct ath5k_hw *ah,
                        s16 *pwr_min, s16 *pwr_max, u8 pdcurves)
{
        u8 gain_boundaries[AR5K_EEPROM_N_PD_GAINS];
        u8 *pdadc_out = ah->ah_txpower.txp_pd_table;
        u8 *pdadc_tmp;
        s16 pdadc_0;
        u8 pdadc_i, pdadc_n, pwr_step, pdg, max_idx, table_size;
        u8 pd_gain_overlap;

        /* Note: Register value is initialized on initvals
         * there is no feedback from hw.
         * XXX: What about pd_gain_overlap from EEPROM ? */
        pd_gain_overlap = (u8) ath5k_hw_reg_read(ah, AR5K_PHY_TPC_RG5) &
                AR5K_PHY_TPC_RG5_PD_GAIN_OVERLAP;

        /* Create final PDADC table */
        for (pdg = 0, pdadc_i = 0; pdg < pdcurves; pdg++) {
                pdadc_tmp = ah->ah_txpower.tmpL[pdg];

                if (pdg == pdcurves - 1)
                        /* 2 dB boundary stretch for last
                         * (higher power) curve */
                        gain_boundaries[pdg] = pwr_max[pdg] + 4;
                else
                        /* Set gain boundary in the middle
                         * between this curve and the next one */
                        gain_boundaries[pdg] =
                                (pwr_max[pdg] + pwr_min[pdg + 1]) / 2;

                /* Sanity check in case our 2 db stretch got out of
                 * range. */
                if (gain_boundaries[pdg] > AR5K_TUNE_MAX_TXPOWER)
                        gain_boundaries[pdg] = AR5K_TUNE_MAX_TXPOWER;

                /* For the first curve (lower power)
                 * start from 0 dB */
                if (pdg == 0)
                        pdadc_0 = 0;
                else
                        /* For the other curves use the gain overlap */
                        pdadc_0 = (gain_boundaries[pdg - 1] - pwr_min[pdg]) -
                                                        pd_gain_overlap;

                /* Force each power step to be at least 0.5 dB */
                if ((pdadc_tmp[1] - pdadc_tmp[0]) > 1)
                        pwr_step = pdadc_tmp[1] - pdadc_tmp[0];
                else
                        pwr_step = 1;

                /* If pdadc_0 is negative, we need to extrapolate
                 * below this pdgain by a number of pwr_steps */
                while ((pdadc_0 < 0) && (pdadc_i < 128)) {
                        s16 tmp = pdadc_tmp[0] + pdadc_0 * pwr_step;
                        pdadc_out[pdadc_i++] = (tmp < 0) ? 0 : (u8) tmp;
                        pdadc_0++;
                }

                /* Set last pwr level, using gain boundaries */
                pdadc_n = gain_boundaries[pdg] + pd_gain_overlap - pwr_min[pdg];
                /* Limit it to be inside pwr range */
                table_size = pwr_max[pdg] - pwr_min[pdg];
                max_idx = (pdadc_n < table_size) ? pdadc_n : table_size;

                /* Fill pdadc_out table */
                while (pdadc_0 < max_idx && pdadc_i < 128)
                        pdadc_out[pdadc_i++] = pdadc_tmp[pdadc_0++];

                /* Need to extrapolate above this pdgain? */
                if (pdadc_n <= max_idx)
                        continue;

                /* Force each power step to be at least 0.5 dB */
                if ((pdadc_tmp[table_size - 1] - pdadc_tmp[table_size - 2]) > 1)
                        pwr_step = pdadc_tmp[table_size - 1] -
                                                pdadc_tmp[table_size - 2];
                else
                        pwr_step = 1;

                /* Extrapolate above */
                while ((pdadc_0 < (s16) pdadc_n) &&
                (pdadc_i < AR5K_EEPROM_POWER_TABLE_SIZE * 2)) {
                        s16 tmp = pdadc_tmp[table_size - 1] +
                                        (pdadc_0 - max_idx) * pwr_step;
                        pdadc_out[pdadc_i++] = (tmp > 127) ? 127 : (u8) tmp;
                        pdadc_0++;
                }
        }

        while (pdg < AR5K_EEPROM_N_PD_GAINS) {
                gain_boundaries[pdg] = gain_boundaries[pdg - 1];
                pdg++;
        }

        while (pdadc_i < AR5K_EEPROM_POWER_TABLE_SIZE * 2) {
                pdadc_out[pdadc_i] = pdadc_out[pdadc_i - 1];
                pdadc_i++;
        }

        /* Set gain boundaries */
        ath5k_hw_reg_write(ah,
                AR5K_REG_SM(pd_gain_overlap,
                        AR5K_PHY_TPC_RG5_PD_GAIN_OVERLAP) |
                AR5K_REG_SM(gain_boundaries[0],
                        AR5K_PHY_TPC_RG5_PD_GAIN_BOUNDARY_1) |
                AR5K_REG_SM(gain_boundaries[1],
                        AR5K_PHY_TPC_RG5_PD_GAIN_BOUNDARY_2) |
                AR5K_REG_SM(gain_boundaries[2],
                        AR5K_PHY_TPC_RG5_PD_GAIN_BOUNDARY_3) |
                AR5K_REG_SM(gain_boundaries[3],
                        AR5K_PHY_TPC_RG5_PD_GAIN_BOUNDARY_4),
                AR5K_PHY_TPC_RG5);

        /* Used for setting rate power table */
        ah->ah_txpower.txp_min_idx = pwr_min[0];

}

/**
 * ath5k_write_pwr_to_pdadc_table() - Write the PDADC values on hw
 * @ah: The &struct ath5k_hw
 * @ee_mode: One of enum ath5k_driver_mode
 */
static void
ath5k_write_pwr_to_pdadc_table(struct ath5k_hw *ah, u8 ee_mode)
{
        struct ath5k_eeprom_info *ee = &ah->ah_capabilities.cap_eeprom;
        u8 *pdadc_out = ah->ah_txpower.txp_pd_table;
        u8 *pdg_to_idx = ee->ee_pdc_to_idx[ee_mode];
        u8 pdcurves = ee->ee_pd_gains[ee_mode];
        u32 reg;
        u8 i;

        /* Select the right pdgain curves */

        /* Clear current settings */
        reg = ath5k_hw_reg_read(ah, AR5K_PHY_TPC_RG1);
        reg &= ~(AR5K_PHY_TPC_RG1_PDGAIN_1 |
                AR5K_PHY_TPC_RG1_PDGAIN_2 |
                AR5K_PHY_TPC_RG1_PDGAIN_3 |
                AR5K_PHY_TPC_RG1_NUM_PD_GAIN);

        /*
         * Use pd_gains curve from eeprom
         *
         * This overrides the default setting from initvals
         * in case some vendors (e.g. Zcomax) don't use the default
         * curves. If we don't honor their settings we 'll get a
         * 5dB (1 * gain overlap ?) drop.
         */
        reg |= AR5K_REG_SM(pdcurves, AR5K_PHY_TPC_RG1_NUM_PD_GAIN);

        switch (pdcurves) {
        case 3:
                reg |= AR5K_REG_SM(pdg_to_idx[2], AR5K_PHY_TPC_RG1_PDGAIN_3);
                fallthrough;
        case 2:
                reg |= AR5K_REG_SM(pdg_to_idx[1], AR5K_PHY_TPC_RG1_PDGAIN_2);
                fallthrough;
        case 1:
                reg |= AR5K_REG_SM(pdg_to_idx[0], AR5K_PHY_TPC_RG1_PDGAIN_1);
                break;
        }
        ath5k_hw_reg_write(ah, reg, AR5K_PHY_TPC_RG1);

        /*
         * Write TX power values
         */
        for (i = 0; i < (AR5K_EEPROM_POWER_TABLE_SIZE / 2); i++) {
                u32 val = get_unaligned_le32(&pdadc_out[4 * i]);
                ath5k_hw_reg_write(ah, val, AR5K_PHY_PDADC_TXPOWER(i));
        }
}


/*
 * Common code for PCDAC/PDADC tables
 */

/**
 * ath5k_setup_channel_powertable() - Set up power table for this channel
 * @ah: The &struct ath5k_hw
 * @channel: The &struct ieee80211_channel
 * @ee_mode: One of enum ath5k_driver_mode
 * @type: One of enum ath5k_powertable_type (eeprom.h)
 *
 * This is the main function that uses all of the above
 * to set PCDAC/PDADC table on hw for the current channel.
 * This table is used for tx power calibration on the baseband,
 * without it we get weird tx power levels and in some cases
 * distorted spectral mask
 */
static int
ath5k_setup_channel_powertable(struct ath5k_hw *ah,
                        struct ieee80211_channel *channel,
                        u8 ee_mode, u8 type)
{
        struct ath5k_pdgain_info *pdg_L, *pdg_R;
        struct ath5k_chan_pcal_info *pcinfo_L;
        struct ath5k_chan_pcal_info *pcinfo_R;
        struct ath5k_eeprom_info *ee = &ah->ah_capabilities.cap_eeprom;
        u8 *pdg_curve_to_idx = ee->ee_pdc_to_idx[ee_mode];
        s16 table_min[AR5K_EEPROM_N_PD_GAINS];
        s16 table_max[AR5K_EEPROM_N_PD_GAINS];
        u8 *tmpL;
        u8 *tmpR;
        u32 target = channel->center_freq;
        int pdg, i;

        /* Get surrounding freq piers for this channel */
        ath5k_get_chan_pcal_surrounding_piers(ah, channel,
                                                &pcinfo_L,
                                                &pcinfo_R);

        /* Loop over pd gain curves on
         * surrounding freq piers by index */
        for (pdg = 0; pdg < ee->ee_pd_gains[ee_mode]; pdg++) {

                /* Fill curves in reverse order
                 * from lower power (max gain)
                 * to higher power. Use curve -> idx
                 * backmapping we did on eeprom init */
                u8 idx = pdg_curve_to_idx[pdg];

                /* Grab the needed curves by index */
                pdg_L = &pcinfo_L->pd_curves[idx];
                pdg_R = &pcinfo_R->pd_curves[idx];

                /* Initialize the temp tables */
                tmpL = ah->ah_txpower.tmpL[pdg];
                tmpR = ah->ah_txpower.tmpR[pdg];

                /* Set curve's x boundaries and create
                 * curves so that they cover the same
                 * range (if we don't do that one table
                 * will have values on some range and the
                 * other one won't have any so interpolation
                 * will fail) */
                table_min[pdg] = min(pdg_L->pd_pwr[0],
                                        pdg_R->pd_pwr[0]) / 2;

                table_max[pdg] = max(pdg_L->pd_pwr[pdg_L->pd_points - 1],
                                pdg_R->pd_pwr[pdg_R->pd_points - 1]) / 2;

                /* Now create the curves on surrounding channels
                 * and interpolate if needed to get the final
                 * curve for this gain on this channel */
                switch (type) {
                case AR5K_PWRTABLE_LINEAR_PCDAC:
                        /* Override min/max so that we don't loose
                         * accuracy (don't divide by 2) */
                        table_min[pdg] = min(pdg_L->pd_pwr[0],
                                                pdg_R->pd_pwr[0]);

                        table_max[pdg] =
                                max(pdg_L->pd_pwr[pdg_L->pd_points - 1],
                                        pdg_R->pd_pwr[pdg_R->pd_points - 1]);

                        /* Override minimum so that we don't get
                         * out of bounds while extrapolating
                         * below. Don't do this when we have 2
                         * curves and we are on the high power curve
                         * because table_min is ok in this case */
                        if (!(ee->ee_pd_gains[ee_mode] > 1 && pdg == 0)) {

                                table_min[pdg] =
                                        ath5k_get_linear_pcdac_min(pdg_L->pd_step,
                                                                pdg_R->pd_step,
                                                                pdg_L->pd_pwr,
                                                                pdg_R->pd_pwr);

                                /* Don't go too low because we will
                                 * miss the upper part of the curve.
                                 * Note: 126 = 31.5dB (max power supported)
                                 * in 0.25dB units */
                                if (table_max[pdg] - table_min[pdg] > 126)
                                        table_min[pdg] = table_max[pdg] - 126;
                        }

                        fallthrough;
                case AR5K_PWRTABLE_PWR_TO_PCDAC:
                case AR5K_PWRTABLE_PWR_TO_PDADC:

                        ath5k_create_power_curve(table_min[pdg],
                                                table_max[pdg],
                                                pdg_L->pd_pwr,
                                                pdg_L->pd_step,
                                                pdg_L->pd_points, tmpL, type);

                        /* We are in a calibration
                         * pier, no need to interpolate
                         * between freq piers */
                        if (pcinfo_L == pcinfo_R)
                                continue;

                        ath5k_create_power_curve(table_min[pdg],
                                                table_max[pdg],
                                                pdg_R->pd_pwr,
                                                pdg_R->pd_step,
                                                pdg_R->pd_points, tmpR, type);
                        break;
                default:
                        return -EINVAL;
                }

                /* Interpolate between curves
                 * of surrounding freq piers to
                 * get the final curve for this
                 * pd gain. Re-use tmpL for interpolation
                 * output */
                for (i = 0; (i < (u16) (table_max[pdg] - table_min[pdg])) &&
                (i < AR5K_EEPROM_POWER_TABLE_SIZE); i++) {
                        tmpL[i] = (u8) ath5k_get_interpolated_value(target,
                                                        (s16) pcinfo_L->freq,
                                                        (s16) pcinfo_R->freq,
                                                        (s16) tmpL[i],
                                                        (s16) tmpR[i]);
                }
        }

        /* Now we have a set of curves for this
         * channel on tmpL (x range is table_max - table_min
         * and y values are tmpL[pdg][]) sorted in the same
         * order as EEPROM (because we've used the backmapping).
         * So for RF5112 it's from higher power to lower power
         * and for RF2413 it's from lower power to higher power.
         * For RF5111 we only have one curve. */

        /* Fill min and max power levels for this
         * channel by interpolating the values on
         * surrounding channels to complete the dataset */
        ah->ah_txpower.txp_min_pwr = ath5k_get_interpolated_value(target,
                                        (s16) pcinfo_L->freq,
                                        (s16) pcinfo_R->freq,
                                        pcinfo_L->min_pwr, pcinfo_R->min_pwr);

        ah->ah_txpower.txp_max_pwr = ath5k_get_interpolated_value(target,
                                        (s16) pcinfo_L->freq,
                                        (s16) pcinfo_R->freq,
                                        pcinfo_L->max_pwr, pcinfo_R->max_pwr);

        /* Fill PCDAC/PDADC table */
        switch (type) {
        case AR5K_PWRTABLE_LINEAR_PCDAC:
                /* For RF5112 we can have one or two curves
                 * and each curve covers a certain power lvl
                 * range so we need to do some more processing */
                ath5k_combine_linear_pcdac_curves(ah, table_min, table_max,
                                                ee->ee_pd_gains[ee_mode]);

                /* Set txp.offset so that we can
                 * match max power value with max
                 * table index */
                ah->ah_txpower.txp_offset = 64 - (table_max[0] / 2);
                break;
        case AR5K_PWRTABLE_PWR_TO_PCDAC:
                /* We are done for RF5111 since it has only
                 * one curve, just fit the curve on the table */
                ath5k_fill_pwr_to_pcdac_table(ah, table_min, table_max);

                /* No rate powertable adjustment for RF5111 */
                ah->ah_txpower.txp_min_idx = 0;
                ah->ah_txpower.txp_offset = 0;
                break;
        case AR5K_PWRTABLE_PWR_TO_PDADC:
                /* Set PDADC boundaries and fill
                 * final PDADC table */
                ath5k_combine_pwr_to_pdadc_curves(ah, table_min, table_max,
                                                ee->ee_pd_gains[ee_mode]);

                /* Set txp.offset, note that table_min
                 * can be negative */
                ah->ah_txpower.txp_offset = table_min[0];
                break;
        default:
                return -EINVAL;
        }

        ah->ah_txpower.txp_setup = true;

        return 0;
}

/**
 * ath5k_write_channel_powertable() - Set power table for current channel on hw
 * @ah: The &struct ath5k_hw
 * @ee_mode: One of enum ath5k_driver_mode
 * @type: One of enum ath5k_powertable_type (eeprom.h)
 */
static void
ath5k_write_channel_powertable(struct ath5k_hw *ah, u8 ee_mode, u8 type)
{
        if (type == AR5K_PWRTABLE_PWR_TO_PDADC)
                ath5k_write_pwr_to_pdadc_table(ah, ee_mode);
        else
                ath5k_write_pcdac_table(ah);
}


/**
 * DOC: Per-rate tx power setting
 *
 * This is the code that sets the desired tx power limit (below
 * maximum) on hw for each rate (we also have TPC that sets
 * power per packet type). We do that by providing an index on the
 * PCDAC/PDADC table we set up above, for each rate.
 *
 * For now we only limit txpower based on maximum tx power
 * supported by hw (what's inside rate_info) + conformance test
 * limits. We need to limit this even more, based on regulatory domain
 * etc to be safe. Normally this is done from above so we don't care
 * here, all we care is that the tx power we set will be O.K.
 * for the hw (e.g. won't create noise on PA etc).
 *
 * Rate power table contains indices to PCDAC/PDADC table (0.5dB steps -
 * x values) and is indexed as follows:
 * rates[0] - rates[7] -> OFDM rates
 * rates[8] - rates[14] -> CCK rates
 * rates[15] -> XR rates (they all have the same power)
 */

/**
 * ath5k_setup_rate_powertable() - Set up rate power table for a given tx power
 * @ah: The &struct ath5k_hw
 * @max_pwr: The maximum tx power requested in 0.5dB steps
 * @rate_info: The &struct ath5k_rate_pcal_info to fill
 * @ee_mode: One of enum ath5k_driver_mode
 */
static void
ath5k_setup_rate_powertable(struct ath5k_hw *ah, u16 max_pwr,
                        struct ath5k_rate_pcal_info *rate_info,
                        u8 ee_mode)
{
        unsigned int i;
        u16 *rates;
        s16 rate_idx_scaled = 0;

        /* max_pwr is power level we got from driver/user in 0.5dB
         * units, switch to 0.25dB units so we can compare */
        max_pwr *= 2;
        max_pwr = min(max_pwr, (u16) ah->ah_txpower.txp_max_pwr) / 2;

        /* apply rate limits */
        rates = ah->ah_txpower.txp_rates_power_table;

        /* OFDM rates 6 to 24Mb/s */
        for (i = 0; i < 5; i++)
                rates[i] = min(max_pwr, rate_info->target_power_6to24);

        /* Rest OFDM rates */
        rates[5] = min(rates[0], rate_info->target_power_36);
        rates[6] = min(rates[0], rate_info->target_power_48);
        rates[7] = min(rates[0], rate_info->target_power_54);

        /* CCK rates */
        /* 1L */
        rates[8] = min(rates[0], rate_info->target_power_6to24);
        /* 2L */
        rates[9] = min(rates[0], rate_info->target_power_36);
        /* 2S */
        rates[10] = min(rates[0], rate_info->target_power_36);
        /* 5L */
        rates[11] = min(rates[0], rate_info->target_power_48);
        /* 5S */
        rates[12] = min(rates[0], rate_info->target_power_48);
        /* 11L */
        rates[13] = min(rates[0], rate_info->target_power_54);
        /* 11S */
        rates[14] = min(rates[0], rate_info->target_power_54);

        /* XR rates */
        rates[15] = min(rates[0], rate_info->target_power_6to24);

        /* CCK rates have different peak to average ratio
         * so we have to tweak their power so that gainf
         * correction works ok. For this we use OFDM to
         * CCK delta from eeprom */
        if ((ee_mode == AR5K_EEPROM_MODE_11G) &&
        (ah->ah_phy_revision < AR5K_SREV_PHY_5212A))
                for (i = 8; i <= 15; i++)
                        rates[i] -= ah->ah_txpower.txp_cck_ofdm_gainf_delta;

        /* Save min/max and current tx power for this channel
         * in 0.25dB units.
         *
         * Note: We use rates[0] for current tx power because
         * it covers most of the rates, in most cases. It's our
         * tx power limit and what the user expects to see. */
        ah->ah_txpower.txp_min_pwr = 2 * rates[7];
        ah->ah_txpower.txp_cur_pwr = 2 * rates[0];

        /* Set max txpower for correct OFDM operation on all rates
         * -that is the txpower for 54Mbit-, it's used for the PAPD
         * gain probe and it's in 0.5dB units */
        ah->ah_txpower.txp_ofdm = rates[7];

        /* Now that we have all rates setup use table offset to
         * match the power range set by user with the power indices
         * on PCDAC/PDADC table */
        for (i = 0; i < 16; i++) {
                rate_idx_scaled = rates[i] + ah->ah_txpower.txp_offset;
                /* Don't get out of bounds */
                if (rate_idx_scaled > 63)
                        rate_idx_scaled = 63;
                if (rate_idx_scaled < 0)
                        rate_idx_scaled = 0;
                rates[i] = rate_idx_scaled;
        }
}


/**
 * ath5k_hw_txpower() - Set transmission power limit for a given channel
 * @ah: The &struct ath5k_hw
 * @channel: The &struct ieee80211_channel
 * @txpower: Requested tx power in 0.5dB steps
 *
 * Combines all of the above to set the requested tx power limit
 * on hw.
 */
static int
ath5k_hw_txpower(struct ath5k_hw *ah, struct ieee80211_channel *channel,
                 u8 txpower)
{
        struct ath5k_rate_pcal_info rate_info;
        struct ieee80211_channel *curr_channel = ah->ah_current_channel;
        int ee_mode;
        u8 type;
        int ret;

        if (txpower > AR5K_TUNE_MAX_TXPOWER) {
                ATH5K_ERR(ah, "invalid tx power: %u\n", txpower);
                return -EINVAL;
        }

        ee_mode = ath5k_eeprom_mode_from_channel(ah, channel);

        /* Initialize TX power table */
        switch (ah->ah_radio) {
        case AR5K_RF5110:
                /* TODO */
                return 0;
        case AR5K_RF5111:
                type = AR5K_PWRTABLE_PWR_TO_PCDAC;
                break;
        case AR5K_RF5112:
                type = AR5K_PWRTABLE_LINEAR_PCDAC;
                break;
        case AR5K_RF2413:
        case AR5K_RF5413:
        case AR5K_RF2316:
        case AR5K_RF2317:
        case AR5K_RF2425:
                type = AR5K_PWRTABLE_PWR_TO_PDADC;
                break;
        default:
                return -EINVAL;
        }

        /*
         * If we don't change channel/mode skip tx powertable calculation
         * and use the cached one.
         */
        if (!ah->ah_txpower.txp_setup ||
            (channel->hw_value != curr_channel->hw_value) ||
            (channel->center_freq != curr_channel->center_freq)) {
                /* Reset TX power values but preserve requested
                 * tx power from above */
                int requested_txpower = ah->ah_txpower.txp_requested;

                memset(&ah->ah_txpower, 0, sizeof(ah->ah_txpower));

                /* Restore TPC setting and requested tx power */
                ah->ah_txpower.txp_tpc = AR5K_TUNE_TPC_TXPOWER;

                ah->ah_txpower.txp_requested = requested_txpower;

                /* Calculate the powertable */
                ret = ath5k_setup_channel_powertable(ah, channel,
                                                        ee_mode, type);
                if (ret)
                        return ret;
        }

        /* Write table on hw */
        ath5k_write_channel_powertable(ah, ee_mode, type);

        /* Limit max power if we have a CTL available */
        ath5k_get_max_ctl_power(ah, channel);

        /* FIXME: Antenna reduction stuff */

        /* FIXME: Limit power on turbo modes */

        /* FIXME: TPC scale reduction */

        /* Get surrounding channels for per-rate power table
         * calibration */
        ath5k_get_rate_pcal_data(ah, channel, &rate_info);

        /* Setup rate power table */
        ath5k_setup_rate_powertable(ah, txpower, &rate_info, ee_mode);

        /* Write rate power table on hw */
        ath5k_hw_reg_write(ah, AR5K_TXPOWER_OFDM(3, 24) |
                AR5K_TXPOWER_OFDM(2, 16) | AR5K_TXPOWER_OFDM(1, 8) |
                AR5K_TXPOWER_OFDM(0, 0), AR5K_PHY_TXPOWER_RATE1);

        ath5k_hw_reg_write(ah, AR5K_TXPOWER_OFDM(7, 24) |
                AR5K_TXPOWER_OFDM(6, 16) | AR5K_TXPOWER_OFDM(5, 8) |
                AR5K_TXPOWER_OFDM(4, 0), AR5K_PHY_TXPOWER_RATE2);

        ath5k_hw_reg_write(ah, AR5K_TXPOWER_CCK(10, 24) |
                AR5K_TXPOWER_CCK(9, 16) | AR5K_TXPOWER_CCK(15, 8) |
                AR5K_TXPOWER_CCK(8, 0), AR5K_PHY_TXPOWER_RATE3);

        ath5k_hw_reg_write(ah, AR5K_TXPOWER_CCK(14, 24) |
                AR5K_TXPOWER_CCK(13, 16) | AR5K_TXPOWER_CCK(12, 8) |
                AR5K_TXPOWER_CCK(11, 0), AR5K_PHY_TXPOWER_RATE4);

        /* FIXME: TPC support */
        if (ah->ah_txpower.txp_tpc) {
                ath5k_hw_reg_write(ah, AR5K_PHY_TXPOWER_RATE_MAX_TPC_ENABLE |
                        AR5K_TUNE_MAX_TXPOWER, AR5K_PHY_TXPOWER_RATE_MAX);

                ath5k_hw_reg_write(ah,
                        AR5K_REG_MS(AR5K_TUNE_MAX_TXPOWER, AR5K_TPC_ACK) |
                        AR5K_REG_MS(AR5K_TUNE_MAX_TXPOWER, AR5K_TPC_CTS) |
                        AR5K_REG_MS(AR5K_TUNE_MAX_TXPOWER, AR5K_TPC_CHIRP),
                        AR5K_TPC);
        } else {
                ath5k_hw_reg_write(ah, AR5K_TUNE_MAX_TXPOWER,
                        AR5K_PHY_TXPOWER_RATE_MAX);
        }

        return 0;
}

/**
 * ath5k_hw_set_txpower_limit() - Set txpower limit for the current channel
 * @ah: The &struct ath5k_hw
 * @txpower: The requested tx power limit in 0.5dB steps
 *
 * This function provides access to ath5k_hw_txpower to the driver in
 * case user or an application changes it while PHY is running.
 */
int
ath5k_hw_set_txpower_limit(struct ath5k_hw *ah, u8 txpower)
{
        ATH5K_DBG(ah, ATH5K_DEBUG_TXPOWER,
                "changing txpower to %d\n", txpower);

        return ath5k_hw_txpower(ah, ah->ah_current_channel, txpower);
}


/*************\
 Init function
\*************/

/**
 * ath5k_hw_phy_init() - Initialize PHY
 * @ah: The &struct ath5k_hw
 * @channel: The @struct ieee80211_channel
 * @mode: One of enum ath5k_driver_mode
 * @fast: Try a fast channel switch instead
 *
 * This is the main function used during reset to initialize PHY
 * or do a fast channel change if possible.
 *
 * NOTE: Do not call this one from the driver, it assumes PHY is in a
 * warm reset state !
 */
int
ath5k_hw_phy_init(struct ath5k_hw *ah, struct ieee80211_channel *channel,
                      u8 mode, bool fast)
{
        struct ieee80211_channel *curr_channel;
        int ret, i;
        u32 phy_tst1;
        ret = 0;

        /*
         * Sanity check for fast flag
         * Don't try fast channel change when changing modulation
         * mode/band. We check for chip compatibility on
         * ath5k_hw_reset.
         */
        curr_channel = ah->ah_current_channel;
        if (fast && (channel->hw_value != curr_channel->hw_value))
                return -EINVAL;

        /*
         * On fast channel change we only set the synth parameters
         * while PHY is running, enable calibration and skip the rest.
         */
        if (fast) {
                AR5K_REG_ENABLE_BITS(ah, AR5K_PHY_RFBUS_REQ,
                                    AR5K_PHY_RFBUS_REQ_REQUEST);
                for (i = 0; i < 100; i++) {
                        if (ath5k_hw_reg_read(ah, AR5K_PHY_RFBUS_GRANT))
                                break;
                        udelay(5);
                }
                /* Failed */
                if (i >= 100)
                        return -EIO;

                /* Set channel and wait for synth */
                ret = ath5k_hw_channel(ah, channel);
                if (ret)
                        return ret;

                ath5k_hw_wait_for_synth(ah, channel);
        }

        /*
         * Set TX power
         *
         * Note: We need to do that before we set
         * RF buffer settings on 5211/5212+ so that we
         * properly set curve indices.
         */
        ret = ath5k_hw_txpower(ah, channel, ah->ah_txpower.txp_requested ?
                                        ah->ah_txpower.txp_requested * 2 :
                                        AR5K_TUNE_MAX_TXPOWER);
        if (ret)
                return ret;

        /* Write OFDM timings on 5212*/
        if (ah->ah_version == AR5K_AR5212 &&
                channel->hw_value != AR5K_MODE_11B) {

                ret = ath5k_hw_write_ofdm_timings(ah, channel);
                if (ret)
                        return ret;

                /* Spur info is available only from EEPROM versions
                 * greater than 5.3, but the EEPROM routines will use
                 * static values for older versions */
                if (ah->ah_mac_srev >= AR5K_SREV_AR5424)
                        ath5k_hw_set_spur_mitigation_filter(ah,
                                                            channel);
        }

        /* If we used fast channel switching
         * we are done, release RF bus and
         * fire up NF calibration.
         *
         * Note: Only NF calibration due to
         * channel change, not AGC calibration
         * since AGC is still running !
         */
        if (fast) {
                /*
                 * Release RF Bus grant
                 */
                AR5K_REG_DISABLE_BITS(ah, AR5K_PHY_RFBUS_REQ,
                                    AR5K_PHY_RFBUS_REQ_REQUEST);

                /*
                 * Start NF calibration
                 */
                AR5K_REG_ENABLE_BITS(ah, AR5K_PHY_AGCCTL,
                                        AR5K_PHY_AGCCTL_NF);

                return ret;
        }

        /*
         * For 5210 we do all initialization using
         * initvals, so we don't have to modify
         * any settings (5210 also only supports
         * a/aturbo modes)
         */
        if (ah->ah_version != AR5K_AR5210) {

                /*
                 * Write initial RF gain settings
                 * This should work for both 5111/5112
                 */
                ret = ath5k_hw_rfgain_init(ah, channel->band);
                if (ret)
                        return ret;

                usleep_range(1000, 1500);

                /*
                 * Write RF buffer
                 */
                ret = ath5k_hw_rfregs_init(ah, channel, mode);
                if (ret)
                        return ret;

                /*Enable/disable 802.11b mode on 5111
                (enable 2111 frequency converter + CCK)*/
                if (ah->ah_radio == AR5K_RF5111) {
                        if (mode == AR5K_MODE_11B)
                                AR5K_REG_ENABLE_BITS(ah, AR5K_TXCFG,
                                    AR5K_TXCFG_B_MODE);
                        else
                                AR5K_REG_DISABLE_BITS(ah, AR5K_TXCFG,
                                    AR5K_TXCFG_B_MODE);
                }

        } else if (ah->ah_version == AR5K_AR5210) {
                usleep_range(1000, 1500);
                /* Disable phy and wait */
                ath5k_hw_reg_write(ah, AR5K_PHY_ACT_DISABLE, AR5K_PHY_ACT);
                usleep_range(1000, 1500);
        }

        /* Set channel on PHY */
        ret = ath5k_hw_channel(ah, channel);
        if (ret)
                return ret;

        /*
         * Enable the PHY and wait until completion
         * This includes BaseBand and Synthesizer
         * activation.
         */
        ath5k_hw_reg_write(ah, AR5K_PHY_ACT_ENABLE, AR5K_PHY_ACT);

        ath5k_hw_wait_for_synth(ah, channel);

        /*
         * Perform ADC test to see if baseband is ready
         * Set tx hold and check adc test register
         */
        phy_tst1 = ath5k_hw_reg_read(ah, AR5K_PHY_TST1);
        ath5k_hw_reg_write(ah, AR5K_PHY_TST1_TXHOLD, AR5K_PHY_TST1);
        for (i = 0; i <= 20; i++) {
                if (!(ath5k_hw_reg_read(ah, AR5K_PHY_ADC_TEST) & 0x10))
                        break;
                usleep_range(200, 250);
        }
        ath5k_hw_reg_write(ah, phy_tst1, AR5K_PHY_TST1);

        /*
         * Start automatic gain control calibration
         *
         * During AGC calibration RX path is re-routed to
         * a power detector so we don't receive anything.
         *
         * This method is used to calibrate some static offsets
         * used together with on-the fly I/Q calibration (the
         * one performed via ath5k_hw_phy_calibrate), which doesn't
         * interrupt rx path.
         *
         * While rx path is re-routed to the power detector we also
         * start a noise floor calibration to measure the
         * card's noise floor (the noise we measure when we are not
         * transmitting or receiving anything).
         *
         * If we are in a noisy environment, AGC calibration may time
         * out and/or noise floor calibration might timeout.
         */
        AR5K_REG_ENABLE_BITS(ah, AR5K_PHY_AGCCTL,
                                AR5K_PHY_AGCCTL_CAL | AR5K_PHY_AGCCTL_NF);

        /* At the same time start I/Q calibration for QAM constellation
         * -no need for CCK- */
        ah->ah_iq_cal_needed = false;
        if (!(mode == AR5K_MODE_11B)) {
                ah->ah_iq_cal_needed = true;
                AR5K_REG_WRITE_BITS(ah, AR5K_PHY_IQ,
                                AR5K_PHY_IQ_CAL_NUM_LOG_MAX, 15);
                AR5K_REG_ENABLE_BITS(ah, AR5K_PHY_IQ,
                                AR5K_PHY_IQ_RUN);
        }

        /* Wait for gain calibration to finish (we check for I/Q calibration
         * during ath5k_phy_calibrate) */
        if (ath5k_hw_register_timeout(ah, AR5K_PHY_AGCCTL,
                        AR5K_PHY_AGCCTL_CAL, 0, false)) {
                ATH5K_ERR(ah, "gain calibration timeout (%uMHz)\n",
                        channel->center_freq);
        }

        /* Restore antenna mode */
        ath5k_hw_set_antenna_mode(ah, ah->ah_ant_mode);

        return ret;
}