1 files changed, 159 insertions, 42 deletions

diff --git a/net/wireless/reg.c b/net/wireless/reg.c
index 537af62ec42b..d897528ee7fc 100644
--- a/net/wireless/reg.c
+++ b/net/wireless/reg.c
@@ -48,12 +48,6 @@ static struct regulatory_request *last_request;
 /* To trigger userspace events */
 static struct platform_device *reg_pdev;
 
-/* Keep the ordering from large to small */
-static u32 supported_bandwidths[] = {
-        MHZ_TO_KHZ(40),
-        MHZ_TO_KHZ(20),
-};
-
 /*
  * Central wireless core regulatory domains, we only need two,
  * the current one and a world regulatory domain in case we have no
@@ -435,19 +429,20 @@ static bool is_valid_rd(const struct ieee80211_regdomain *rd)
         return true;
 }
 
-/* Returns value in KHz */
-static u32 freq_max_bandwidth(const struct ieee80211_freq_range *freq_range,
-        u32 freq)
+static bool reg_does_bw_fit(const struct ieee80211_freq_range *freq_range,
+                            u32 center_freq_khz,
+                            u32 bw_khz)
 {
-        unsigned int i;
-        for (i = 0; i < ARRAY_SIZE(supported_bandwidths); i++) {
-                u32 start_freq_khz = freq - supported_bandwidths[i]/2;
-                u32 end_freq_khz = freq + supported_bandwidths[i]/2;
-                if (start_freq_khz >= freq_range->start_freq_khz &&
-                        end_freq_khz <= freq_range->end_freq_khz)
-                        return supported_bandwidths[i];
-        }
-        return 0;
+        u32 start_freq_khz, end_freq_khz;
+
+        start_freq_khz = center_freq_khz - (bw_khz/2);
+        end_freq_khz = center_freq_khz + (bw_khz/2);
+
+        if (start_freq_khz >= freq_range->start_freq_khz &&
+            end_freq_khz <= freq_range->end_freq_khz)
+                return true;
+
+        return false;
 }
 
 /**
@@ -847,14 +842,17 @@ static u32 map_regdom_flags(u32 rd_flags)
 
 static int freq_reg_info_regd(struct wiphy *wiphy,
                               u32 center_freq,
-                              u32 *bandwidth,
+                              u32 desired_bw_khz,
                               const struct ieee80211_reg_rule **reg_rule,
                               const struct ieee80211_regdomain *custom_regd)
 {
         int i;
         bool band_rule_found = false;
         const struct ieee80211_regdomain *regd;
-        u32 max_bandwidth = 0;
+        bool bw_fits = false;
+
+        if (!desired_bw_khz)
+                desired_bw_khz = MHZ_TO_KHZ(20);
 
         regd = custom_regd ? custom_regd : cfg80211_regdomain;
 
@@ -887,38 +885,54 @@ static int freq_reg_info_regd(struct wiphy *wiphy,
                 if (!band_rule_found)
                         band_rule_found = freq_in_rule_band(fr, center_freq);
 
-                max_bandwidth = freq_max_bandwidth(fr, center_freq);
+                bw_fits = reg_does_bw_fit(fr,
+                                          center_freq,
+                                          desired_bw_khz);
 
-                if (max_bandwidth && *bandwidth <= max_bandwidth) {
+                if (band_rule_found && bw_fits) {
                         *reg_rule = rr;
-                        *bandwidth = max_bandwidth;
-                        break;
+                        return 0;
                 }
         }
 
         if (!band_rule_found)
                 return -ERANGE;
 
-        return !max_bandwidth;
+        return -EINVAL;
 }
 EXPORT_SYMBOL(freq_reg_info);
 
-int freq_reg_info(struct wiphy *wiphy, u32 center_freq, u32 *bandwidth,
-                         const struct ieee80211_reg_rule **reg_rule)
+int freq_reg_info(struct wiphy *wiphy,
+                  u32 center_freq,
+                  u32 desired_bw_khz,
+                  const struct ieee80211_reg_rule **reg_rule)
 {
         assert_cfg80211_lock();
-        return freq_reg_info_regd(wiphy, center_freq,
-                bandwidth, reg_rule, NULL);
+        return freq_reg_info_regd(wiphy,
+                                  center_freq,
+                                  desired_bw_khz,
+                                  reg_rule,
+                                  NULL);
 }
 
+/*
+ * Note that right now we assume the desired channel bandwidth
+ * is always 20 MHz for each individual channel (HT40 uses 20 MHz
+ * per channel, the primary and the extension channel). To support
+ * smaller custom bandwidths such as 5 MHz or 10 MHz we'll need a
+ * new ieee80211_channel.target_bw and re run the regulatory check
+ * on the wiphy with the target_bw specified. Then we can simply use
+ * that below for the desired_bw_khz below.
+ */
 static void handle_channel(struct wiphy *wiphy, enum ieee80211_band band,
                            unsigned int chan_idx)
 {
         int r;
-        u32 flags;
-        u32 max_bandwidth = 0;
+        u32 flags, bw_flags = 0;
+        u32 desired_bw_khz = MHZ_TO_KHZ(20);
         const struct ieee80211_reg_rule *reg_rule = NULL;
         const struct ieee80211_power_rule *power_rule = NULL;
+        const struct ieee80211_freq_range *freq_range = NULL;
         struct ieee80211_supported_band *sband;
         struct ieee80211_channel *chan;
         struct wiphy *request_wiphy = NULL;
@@ -933,8 +947,10 @@ static void handle_channel(struct wiphy *wiphy, enum ieee80211_band band,
 
         flags = chan->orig_flags;
 
-        r = freq_reg_info(wiphy, MHZ_TO_KHZ(chan->center_freq),
-                &max_bandwidth, &reg_rule);
+        r = freq_reg_info(wiphy,
+                          MHZ_TO_KHZ(chan->center_freq),
+                          desired_bw_khz,
+                          &reg_rule);
 
         if (r) {
                 /*
@@ -977,6 +993,10 @@ static void handle_channel(struct wiphy *wiphy, enum ieee80211_band band,
         }
 
         power_rule = &reg_rule->power_rule;
+        freq_range = &reg_rule->freq_range;
+
+        if (freq_range->max_bandwidth_khz < MHZ_TO_KHZ(40))
+                bw_flags = IEEE80211_CHAN_NO_HT40;
 
         if (last_request->initiator == NL80211_REGDOM_SET_BY_DRIVER &&
             request_wiphy && request_wiphy == wiphy &&
@@ -987,19 +1007,19 @@ static void handle_channel(struct wiphy *wiphy, enum ieee80211_band band,
                  * settings
                  */
                 chan->flags = chan->orig_flags =
-                        map_regdom_flags(reg_rule->flags);
+                        map_regdom_flags(reg_rule->flags) | bw_flags;
                 chan->max_antenna_gain = chan->orig_mag =
                         (int) MBI_TO_DBI(power_rule->max_antenna_gain);
-                chan->max_bandwidth = KHZ_TO_MHZ(max_bandwidth);
+                chan->max_bandwidth = KHZ_TO_MHZ(desired_bw_khz);
                 chan->max_power = chan->orig_mpwr =
                         (int) MBM_TO_DBM(power_rule->max_eirp);
                 return;
         }
 
-        chan->flags = flags | map_regdom_flags(reg_rule->flags);
+        chan->flags = flags | bw_flags | map_regdom_flags(reg_rule->flags);
         chan->max_antenna_gain = min(chan->orig_mag,
                 (int) MBI_TO_DBI(power_rule->max_antenna_gain));
-        chan->max_bandwidth = KHZ_TO_MHZ(max_bandwidth);
+        chan->max_bandwidth = KHZ_TO_MHZ(desired_bw_khz);
         if (chan->orig_mpwr)
                 chan->max_power = min(chan->orig_mpwr,
                         (int) MBM_TO_DBM(power_rule->max_eirp));
@@ -1156,6 +1176,93 @@ static void reg_process_beacons(struct wiphy *wiphy)
         wiphy_update_beacon_reg(wiphy);
 }
 
+static bool is_ht40_not_allowed(struct ieee80211_channel *chan)
+{
+        if (!chan)
+                return true;
+        if (chan->flags & IEEE80211_CHAN_DISABLED)
+                return true;
+        /* This would happen when regulatory rules disallow HT40 completely */
+        if (IEEE80211_CHAN_NO_HT40 == (chan->flags & (IEEE80211_CHAN_NO_HT40)))
+                return true;
+        return false;
+}
+
+static void reg_process_ht_flags_channel(struct wiphy *wiphy,
+                                         enum ieee80211_band band,
+                                         unsigned int chan_idx)
+{
+        struct ieee80211_supported_band *sband;
+        struct ieee80211_channel *channel;
+        struct ieee80211_channel *channel_before = NULL, *channel_after = NULL;
+        unsigned int i;
+
+        assert_cfg80211_lock();
+
+        sband = wiphy->bands[band];
+        BUG_ON(chan_idx >= sband->n_channels);
+        channel = &sband->channels[chan_idx];
+
+        if (is_ht40_not_allowed(channel)) {
+                channel->flags |= IEEE80211_CHAN_NO_HT40;
+                return;
+        }
+
+        /*
+         * We need to ensure the extension channels exist to
+         * be able to use HT40- or HT40+, this finds them (or not)
+         */
+        for (i = 0; i < sband->n_channels; i++) {
+                struct ieee80211_channel *c = &sband->channels[i];
+                if (c->center_freq == (channel->center_freq - 20))
+                        channel_before = c;
+                if (c->center_freq == (channel->center_freq + 20))
+                        channel_after = c;
+        }
+
+        /*
+         * Please note that this assumes target bandwidth is 20 MHz,
+         * if that ever changes we also need to change the below logic
+         * to include that as well.
+         */
+        if (is_ht40_not_allowed(channel_before))
+                channel->flags |= IEEE80211_CHAN_NO_FAT_BELOW;
+        else
+                channel->flags &= ~IEEE80211_CHAN_NO_FAT_BELOW;
+
+        if (is_ht40_not_allowed(channel_after))
+                channel->flags |= IEEE80211_CHAN_NO_FAT_ABOVE;
+        else
+                channel->flags &= ~IEEE80211_CHAN_NO_FAT_ABOVE;
+}
+
+static void reg_process_ht_flags_band(struct wiphy *wiphy,
+                                      enum ieee80211_band band)
+{
+        unsigned int i;
+        struct ieee80211_supported_band *sband;
+
+        BUG_ON(!wiphy->bands[band]);
+        sband = wiphy->bands[band];
+
+        for (i = 0; i < sband->n_channels; i++)
+                reg_process_ht_flags_channel(wiphy, band, i);
+}
+
+static void reg_process_ht_flags(struct wiphy *wiphy)
+{
+        enum ieee80211_band band;
+
+        if (!wiphy)
+                return;
+
+        for (band = 0; band < IEEE80211_NUM_BANDS; band++) {
+                if (wiphy->bands[band])
+                        reg_process_ht_flags_band(wiphy, band);
+        }
+
+}
+
 void wiphy_update_regulatory(struct wiphy *wiphy,
                              enum nl80211_reg_initiator initiator)
 {
@@ -1169,6 +1276,7 @@ void wiphy_update_regulatory(struct wiphy *wiphy,
         }
 out:
         reg_process_beacons(wiphy);
+        reg_process_ht_flags(wiphy);
         if (wiphy->reg_notifier)
                 wiphy->reg_notifier(wiphy, last_request);
 }
@@ -1179,9 +1287,11 @@ static void handle_channel_custom(struct wiphy *wiphy,
                                   const struct ieee80211_regdomain *regd)
 {
         int r;
-        u32 max_bandwidth = 0;
+        u32 desired_bw_khz = MHZ_TO_KHZ(20);
+        u32 bw_flags = 0;
         const struct ieee80211_reg_rule *reg_rule = NULL;
         const struct ieee80211_power_rule *power_rule = NULL;
+        const struct ieee80211_freq_range *freq_range = NULL;
         struct ieee80211_supported_band *sband;
         struct ieee80211_channel *chan;
 
@@ -1191,8 +1301,11 @@ static void handle_channel_custom(struct wiphy *wiphy,
         BUG_ON(chan_idx >= sband->n_channels);
         chan = &sband->channels[chan_idx];
 
-        r = freq_reg_info_regd(wiphy, MHZ_TO_KHZ(chan->center_freq),
-                &max_bandwidth, &reg_rule, regd);
+        r = freq_reg_info_regd(wiphy,
+                               MHZ_TO_KHZ(chan->center_freq),
+                               desired_bw_khz,
+                               &reg_rule,
+                               regd);
 
         if (r) {
                 chan->flags = IEEE80211_CHAN_DISABLED;
@@ -1200,10 +1313,14 @@ static void handle_channel_custom(struct wiphy *wiphy,
         }
 
         power_rule = &reg_rule->power_rule;
+        freq_range = &reg_rule->freq_range;
+
+        if (freq_range->max_bandwidth_khz < MHZ_TO_KHZ(40))
+                bw_flags = IEEE80211_CHAN_NO_HT40;
 
-        chan->flags |= map_regdom_flags(reg_rule->flags);
+        chan->flags |= map_regdom_flags(reg_rule->flags) | bw_flags;
         chan->max_antenna_gain = (int) MBI_TO_DBI(power_rule->max_antenna_gain);
-        chan->max_bandwidth = KHZ_TO_MHZ(max_bandwidth);
+        chan->max_bandwidth = KHZ_TO_MHZ(desired_bw_khz);
         chan->max_power = (int) MBM_TO_DBM(power_rule->max_eirp);
 }