// SPDX-License-Identifier: GPL-2.0
/* Copyright(c) 2009-2012  Realtek Corporation.*/

#include "wifi.h"
#include "regd.h"

static struct country_code_to_enum_rd all_countries[] = {
        {COUNTRY_CODE_FCC, "US"},
        {COUNTRY_CODE_IC, "US"},
        {COUNTRY_CODE_ETSI, "EC"},
        {COUNTRY_CODE_SPAIN, "EC"},
        {COUNTRY_CODE_FRANCE, "EC"},
        {COUNTRY_CODE_MKK, "JP"},
        {COUNTRY_CODE_MKK1, "JP"},
        {COUNTRY_CODE_ISRAEL, "EC"},
        {COUNTRY_CODE_TELEC, "JP"},
        {COUNTRY_CODE_MIC, "JP"},
        {COUNTRY_CODE_GLOBAL_DOMAIN, "JP"},
        {COUNTRY_CODE_WORLD_WIDE_13, "EC"},
        {COUNTRY_CODE_TELEC_NETGEAR, "EC"},
        {COUNTRY_CODE_WORLD_WIDE_13_5G_ALL, "US"},
};

/*
 *Only these channels all allow active
 *scan on all world regulatory domains
 */
#define RTL819x_2GHZ_CH01_11    \
        REG_RULE(2412-10, 2462+10, 40, 0, 20, 0)

/*
 *We enable active scan on these a case
 *by case basis by regulatory domain
 */
#define RTL819x_2GHZ_CH12_13    \
        REG_RULE(2467-10, 2472+10, 40, 0, 20,\
        NL80211_RRF_PASSIVE_SCAN)

#define RTL819x_2GHZ_CH14       \
        REG_RULE(2484-10, 2484+10, 40, 0, 20, \
        NL80211_RRF_PASSIVE_SCAN | \
        NL80211_RRF_NO_OFDM)

/* 5G chan 36 - chan 64*/
#define RTL819x_5GHZ_5150_5350  \
        REG_RULE(5150-10, 5350+10, 80, 0, 30, 0)
/* 5G chan 100 - chan 165*/
#define RTL819x_5GHZ_5470_5850  \
        REG_RULE(5470-10, 5850+10, 80, 0, 30, 0)
/* 5G chan 149 - chan 165*/
#define RTL819x_5GHZ_5725_5850  \
        REG_RULE(5725-10, 5850+10, 80, 0, 30, 0)

#define RTL819x_5GHZ_ALL        \
        (RTL819x_5GHZ_5150_5350, RTL819x_5GHZ_5470_5850)

static const struct ieee80211_regdomain rtl_regdom_11 = {
        .n_reg_rules = 1,
        .alpha2 = "99",
        .reg_rules = {
                      RTL819x_2GHZ_CH01_11,
                      }
};

static const struct ieee80211_regdomain rtl_regdom_12_13 = {
        .n_reg_rules = 2,
        .alpha2 = "99",
        .reg_rules = {
                      RTL819x_2GHZ_CH01_11,
                          RTL819x_2GHZ_CH12_13,
                      }
};

static const struct ieee80211_regdomain rtl_regdom_no_midband = {
        .n_reg_rules = 3,
        .alpha2 = "99",
        .reg_rules = {
                      RTL819x_2GHZ_CH01_11,
                          RTL819x_5GHZ_5150_5350,
                          RTL819x_5GHZ_5725_5850,
                      }
};

static const struct ieee80211_regdomain rtl_regdom_60_64 = {
        .n_reg_rules = 3,
        .alpha2 = "99",
        .reg_rules = {
                      RTL819x_2GHZ_CH01_11,
                          RTL819x_2GHZ_CH12_13,
                          RTL819x_5GHZ_5725_5850,
                      }
};

static const struct ieee80211_regdomain rtl_regdom_14_60_64 = {
        .n_reg_rules = 4,
        .alpha2 = "99",
        .reg_rules = {
                      RTL819x_2GHZ_CH01_11,
                          RTL819x_2GHZ_CH12_13,
                          RTL819x_2GHZ_CH14,
                          RTL819x_5GHZ_5725_5850,
                      }
};

static const struct ieee80211_regdomain rtl_regdom_12_13_5g_all = {
        .n_reg_rules = 4,
        .alpha2 = "99",
        .reg_rules = {
                        RTL819x_2GHZ_CH01_11,
                        RTL819x_2GHZ_CH12_13,
                        RTL819x_5GHZ_5150_5350,
                        RTL819x_5GHZ_5470_5850,
                }
};

static const struct ieee80211_regdomain rtl_regdom_14 = {
        .n_reg_rules = 3,
        .alpha2 = "99",
        .reg_rules = {
                      RTL819x_2GHZ_CH01_11,
                          RTL819x_2GHZ_CH12_13,
                          RTL819x_2GHZ_CH14,
                      }
};

static bool _rtl_is_radar_freq(u16 center_freq)
{
        return center_freq >= 5260 && center_freq <= 5700;
}

static void _rtl_reg_apply_beaconing_flags(struct wiphy *wiphy,
                                           enum nl80211_reg_initiator initiator)
{
        enum nl80211_band band;
        struct ieee80211_supported_band *sband;
        const struct ieee80211_reg_rule *reg_rule;
        struct ieee80211_channel *ch;
        unsigned int i;

        for (band = 0; band < NUM_NL80211_BANDS; band++) {

                if (!wiphy->bands[band])
                        continue;

                sband = wiphy->bands[band];

                for (i = 0; i < sband->n_channels; i++) {
                        ch = &sband->channels[i];
                        if (_rtl_is_radar_freq(ch->center_freq) ||
                            (ch->flags & IEEE80211_CHAN_RADAR))
                                continue;
                        if (initiator == NL80211_REGDOM_SET_BY_COUNTRY_IE) {
                                reg_rule = freq_reg_info(wiphy,
                                                         ch->center_freq);
                                if (IS_ERR(reg_rule))
                                        continue;
                                /*
                                 *If 11d had a rule for this channel ensure
                                 *we enable adhoc/beaconing if it allows us to
                                 *use it. Note that we would have disabled it
                                 *by applying our static world regdomain by
                                 *default during init, prior to calling our
                                 *regulatory_hint().
                                 */

                                if (!(reg_rule->flags & NL80211_RRF_NO_IBSS))
                                        ch->flags &= ~IEEE80211_CHAN_NO_IBSS;
                                if (!(reg_rule->flags &
                                      NL80211_RRF_PASSIVE_SCAN))
                                        ch->flags &=
                                            ~IEEE80211_CHAN_PASSIVE_SCAN;
                        } else {
                                if (ch->beacon_found)
                                        ch->flags &= ~(IEEE80211_CHAN_NO_IBSS |
                                                   IEEE80211_CHAN_PASSIVE_SCAN);
                        }
                }
        }
}

/* Allows active scan on Ch 12 and 13 */
static void _rtl_reg_apply_active_scan_flags(struct wiphy *wiphy,
                                             enum nl80211_reg_initiator
                                             initiator)
{
        struct ieee80211_supported_band *sband;
        struct ieee80211_channel *ch;
        const struct ieee80211_reg_rule *reg_rule;

        if (!wiphy->bands[NL80211_BAND_2GHZ])
                return;
        sband = wiphy->bands[NL80211_BAND_2GHZ];

        /*
         *If no country IE has been received always enable active scan
         *on these channels. This is only done for specific regulatory SKUs
         */
        if (initiator != NL80211_REGDOM_SET_BY_COUNTRY_IE) {
                ch = &sband->channels[11];      /* CH 12 */
                if (ch->flags & IEEE80211_CHAN_PASSIVE_SCAN)
                        ch->flags &= ~IEEE80211_CHAN_PASSIVE_SCAN;
                ch = &sband->channels[12];      /* CH 13 */
                if (ch->flags & IEEE80211_CHAN_PASSIVE_SCAN)
                        ch->flags &= ~IEEE80211_CHAN_PASSIVE_SCAN;
                return;
        }

        /*
         *If a country IE has been received check its rule for this
         *channel first before enabling active scan. The passive scan
         *would have been enforced by the initial processing of our
         *custom regulatory domain.
         */

        ch = &sband->channels[11];      /* CH 12 */
        reg_rule = freq_reg_info(wiphy, ch->center_freq);
        if (!IS_ERR(reg_rule)) {
                if (!(reg_rule->flags & NL80211_RRF_PASSIVE_SCAN))
                        if (ch->flags & IEEE80211_CHAN_PASSIVE_SCAN)
                                ch->flags &= ~IEEE80211_CHAN_PASSIVE_SCAN;
        }

        ch = &sband->channels[12];      /* CH 13 */
        reg_rule = freq_reg_info(wiphy, ch->center_freq);
        if (!IS_ERR(reg_rule)) {
                if (!(reg_rule->flags & NL80211_RRF_PASSIVE_SCAN))
                        if (ch->flags & IEEE80211_CHAN_PASSIVE_SCAN)
                                ch->flags &= ~IEEE80211_CHAN_PASSIVE_SCAN;
        }
}

/*
 *Always apply Radar/DFS rules on
 *freq range 5260 MHz - 5700 MHz
 */
static void _rtl_reg_apply_radar_flags(struct wiphy *wiphy)
{
        struct ieee80211_supported_band *sband;
        struct ieee80211_channel *ch;
        unsigned int i;

        if (!wiphy->bands[NL80211_BAND_5GHZ])
                return;

        sband = wiphy->bands[NL80211_BAND_5GHZ];

        for (i = 0; i < sband->n_channels; i++) {
                ch = &sband->channels[i];
                if (!_rtl_is_radar_freq(ch->center_freq))
                        continue;

                /*
                 *We always enable radar detection/DFS on this
                 *frequency range. Additionally we also apply on
                 *this frequency range:
                 *- If STA mode does not yet have DFS supports disable
                 * active scanning
                 *- If adhoc mode does not support DFS yet then disable
                 * adhoc in the frequency.
                 *- If AP mode does not yet support radar detection/DFS
                 *do not allow AP mode
                 */
                if (!(ch->flags & IEEE80211_CHAN_DISABLED))
                        ch->flags |= IEEE80211_CHAN_RADAR |
                            IEEE80211_CHAN_NO_IBSS |
                            IEEE80211_CHAN_PASSIVE_SCAN;
        }
}

static void _rtl_reg_apply_world_flags(struct wiphy *wiphy,
                                       enum nl80211_reg_initiator initiator,
                                       struct rtl_regulatory *reg)
{
        _rtl_reg_apply_beaconing_flags(wiphy, initiator);
        _rtl_reg_apply_active_scan_flags(wiphy, initiator);
        return;
}

static int _rtl_reg_notifier_apply(struct wiphy *wiphy,
                                   struct regulatory_request *request,
                                   struct rtl_regulatory *reg)
{
        /* We always apply this */
        _rtl_reg_apply_radar_flags(wiphy);

        switch (request->initiator) {
        case NL80211_REGDOM_SET_BY_DRIVER:
        case NL80211_REGDOM_SET_BY_CORE:
        case NL80211_REGDOM_SET_BY_USER:
                break;
        case NL80211_REGDOM_SET_BY_COUNTRY_IE:
                _rtl_reg_apply_world_flags(wiphy, request->initiator, reg);
                break;
        }

        return 0;
}

static const struct ieee80211_regdomain *_rtl_regdomain_select(
                                                struct rtl_regulatory *reg)
{
        switch (reg->country_code) {
        case COUNTRY_CODE_FCC:
                return &rtl_regdom_no_midband;
        case COUNTRY_CODE_IC:
                return &rtl_regdom_11;
        case COUNTRY_CODE_TELEC_NETGEAR:
                return &rtl_regdom_60_64;
        case COUNTRY_CODE_ETSI:
        case COUNTRY_CODE_SPAIN:
        case COUNTRY_CODE_FRANCE:
        case COUNTRY_CODE_ISRAEL:
                return &rtl_regdom_12_13;
        case COUNTRY_CODE_MKK:
        case COUNTRY_CODE_MKK1:
        case COUNTRY_CODE_TELEC:
        case COUNTRY_CODE_MIC:
                return &rtl_regdom_14_60_64;
        case COUNTRY_CODE_GLOBAL_DOMAIN:
                return &rtl_regdom_14;
        case COUNTRY_CODE_WORLD_WIDE_13:
        case COUNTRY_CODE_WORLD_WIDE_13_5G_ALL:
                return &rtl_regdom_12_13_5g_all;
        default:
                return &rtl_regdom_no_midband;
        }
}

static int _rtl_regd_init_wiphy(struct rtl_regulatory *reg,
                                struct wiphy *wiphy,
                                void (*reg_notifier)(struct wiphy *wiphy,
                                                     struct regulatory_request *
                                                     request))
{
        const struct ieee80211_regdomain *regd;

        wiphy->reg_notifier = reg_notifier;

        wiphy->regulatory_flags |= REGULATORY_CUSTOM_REG;
        wiphy->regulatory_flags &= ~REGULATORY_STRICT_REG;
        wiphy->regulatory_flags &= ~REGULATORY_DISABLE_BEACON_HINTS;
        regd = _rtl_regdomain_select(reg);
        wiphy_apply_custom_regulatory(wiphy, regd);
        _rtl_reg_apply_radar_flags(wiphy);
        _rtl_reg_apply_world_flags(wiphy, NL80211_REGDOM_SET_BY_DRIVER, reg);
        return 0;
}

static struct country_code_to_enum_rd *_rtl_regd_find_country(u16 countrycode)
{
        int i;

        for (i = 0; i < ARRAY_SIZE(all_countries); i++) {
                if (all_countries[i].countrycode == countrycode)
                        return &all_countries[i];
        }
        return NULL;
}

static u8 channel_plan_to_country_code(u8 channelplan)
{
        switch (channelplan) {
        case 0x20:
        case 0x21:
                return COUNTRY_CODE_WORLD_WIDE_13;
        case 0x22:
                return COUNTRY_CODE_IC;
        case 0x25:
                return COUNTRY_CODE_ETSI;
        case 0x32:
                return COUNTRY_CODE_TELEC_NETGEAR;
        case 0x41:
                return COUNTRY_CODE_GLOBAL_DOMAIN;
        case 0x7f:
                return COUNTRY_CODE_WORLD_WIDE_13_5G_ALL;
        default:
                return COUNTRY_CODE_MAX; /*Error*/
        }
}

int rtl_regd_init(struct ieee80211_hw *hw,
                  void (*reg_notifier)(struct wiphy *wiphy,
                                       struct regulatory_request *request))
{
        struct rtl_priv *rtlpriv = rtl_priv(hw);
        struct wiphy *wiphy = hw->wiphy;
        struct country_code_to_enum_rd *country = NULL;

        if (!wiphy)
                return -EINVAL;

        /* init country_code from efuse channel plan */
        rtlpriv->regd.country_code =
                channel_plan_to_country_code(rtlpriv->efuse.channel_plan);

        rtl_dbg(rtlpriv, COMP_REGD, DBG_DMESG,
                "rtl: EEPROM regdomain: 0x%0x country code: %d\n",
                rtlpriv->efuse.channel_plan, rtlpriv->regd.country_code);

        if (rtlpriv->regd.country_code >= COUNTRY_CODE_MAX) {
                rtl_dbg(rtlpriv, COMP_REGD, DBG_DMESG,
                        "rtl: EEPROM indicates invalid country code, world wide 13 should be used\n");

                rtlpriv->regd.country_code = COUNTRY_CODE_WORLD_WIDE_13;
        }

        country = _rtl_regd_find_country(rtlpriv->regd.country_code);

        if (country) {
                rtlpriv->regd.alpha2[0] = country->iso_name[0];
                rtlpriv->regd.alpha2[1] = country->iso_name[1];
        } else {
                rtlpriv->regd.alpha2[0] = '0';
                rtlpriv->regd.alpha2[1] = '0';
        }

        rtl_dbg(rtlpriv, COMP_REGD, DBG_TRACE,
                "rtl: Country alpha2 being used: %c%c\n",
                rtlpriv->regd.alpha2[0], rtlpriv->regd.alpha2[1]);

        _rtl_regd_init_wiphy(&rtlpriv->regd, wiphy, reg_notifier);

        return 0;
}

void rtl_reg_notifier(struct wiphy *wiphy, struct regulatory_request *request)
{
        struct ieee80211_hw *hw = wiphy_to_ieee80211_hw(wiphy);
        struct rtl_priv *rtlpriv = rtl_priv(hw);

        rtl_dbg(rtlpriv, COMP_REGD, DBG_LOUD, "\n");

        _rtl_reg_notifier_apply(wiphy, request, &rtlpriv->regd);
}