mt76: mt7915: fix/rewrite the dfs state handling logic
authorFelix Fietkau <nbd@nbd.name>
Wed, 2 Feb 2022 22:11:58 +0000 (23:11 +0100)
committerFelix Fietkau <nbd@nbd.name>
Thu, 3 Feb 2022 15:14:58 +0000 (16:14 +0100)
Client mode on DFS channels was broken, because the old code was activating
the DFS detector on radar channels while leaving it in CAC state.
This was caused by making the decision based on the channel radar flag,
instead of hw->conf.radar_enabled.
In order to properly deal with the various corner cases, rip out the state
handling code and replace it with something that's much easier to reason
about.

Tested-by: Lorenzo Bianconi <lorenzo@kernel.org>
Signed-off-by: Felix Fietkau <nbd@nbd.name>
drivers/net/wireless/mediatek/mt76/mac80211.c
drivers/net/wireless/mediatek/mt76/mt76.h
drivers/net/wireless/mediatek/mt76/mt7915/init.c
drivers/net/wireless/mediatek/mt76/mt7915/mac.c
drivers/net/wireless/mediatek/mt76/mt7915/main.c
drivers/net/wireless/mediatek/mt76/mt7915/mcu.c
drivers/net/wireless/mediatek/mt76/mt7915/mt7915.h

index 148e126b9215ab3af17dd0d538074deec6f8c7d8..a4bb281a74e6917ea9c2365a6f37ac55d15ecc9d 100644 (file)
@@ -823,6 +823,10 @@ void mt76_set_channel(struct mt76_phy *phy)
        wait_event_timeout(dev->tx_wait, !mt76_has_tx_pending(phy), timeout);
        mt76_update_survey(phy);
 
+       if (phy->chandef.chan->center_freq != chandef->chan->center_freq ||
+           phy->chandef.width != chandef->width)
+               phy->dfs_state = MT_DFS_STATE_UNKNOWN;
+
        phy->chandef = *chandef;
        phy->chan_state = mt76_channel_state(phy, chandef->chan);
 
@@ -1604,3 +1608,27 @@ void mt76_ethtool_worker(struct mt76_ethtool_worker_info *wi,
        wi->worker_stat_count = ei - wi->initial_stat_idx;
 }
 EXPORT_SYMBOL_GPL(mt76_ethtool_worker);
+
+enum mt76_dfs_state mt76_phy_dfs_state(struct mt76_phy *phy)
+{
+       struct ieee80211_hw *hw = phy->hw;
+       struct mt76_dev *dev = phy->dev;
+
+       if (dev->region == NL80211_DFS_UNSET ||
+           test_bit(MT76_SCANNING, &phy->state))
+               return MT_DFS_STATE_DISABLED;
+
+       if (!hw->conf.radar_enabled) {
+               if ((hw->conf.flags & IEEE80211_CONF_MONITOR) &&
+                   (phy->chandef.chan->flags & IEEE80211_CHAN_RADAR))
+                       return MT_DFS_STATE_ACTIVE;
+
+               return MT_DFS_STATE_DISABLED;
+       }
+
+       if (phy->chandef.chan->dfs_state != NL80211_DFS_AVAILABLE)
+               return MT_DFS_STATE_CAC;
+
+       return MT_DFS_STATE_ACTIVE;
+}
+EXPORT_SYMBOL_GPL(mt76_phy_dfs_state);
index 43abf0679876615d1ad573c8a5e8873a88792bb3..8d5c484eee5893a5c40a2533594f541df7c57b48 100644 (file)
@@ -105,6 +105,13 @@ enum mt76_cipher_type {
        MT_CIPHER_GCMP_256,
 };
 
+enum mt76_dfs_state {
+       MT_DFS_STATE_UNKNOWN,
+       MT_DFS_STATE_DISABLED,
+       MT_DFS_STATE_CAC,
+       MT_DFS_STATE_ACTIVE,
+};
+
 struct mt76_queue_buf {
        dma_addr_t addr;
        u16 len;
@@ -639,6 +646,7 @@ struct mt76_phy {
        struct ieee80211_channel *main_chan;
 
        struct mt76_channel_state *chan_state;
+       enum mt76_dfs_state dfs_state;
        ktime_t survey_time;
 
        struct mt76_hw_cap cap;
@@ -1184,6 +1192,7 @@ void mt76_sw_scan(struct ieee80211_hw *hw, struct ieee80211_vif *vif,
                  const u8 *mac);
 void mt76_sw_scan_complete(struct ieee80211_hw *hw,
                           struct ieee80211_vif *vif);
+enum mt76_dfs_state mt76_phy_dfs_state(struct mt76_phy *phy);
 int mt76_testmode_cmd(struct ieee80211_hw *hw, struct ieee80211_vif *vif,
                      void *data, int len);
 int mt76_testmode_dump(struct ieee80211_hw *hw, struct sk_buff *skb,
index e908d56a9e21bf6fa36c208b91290718b786023f..705f362b8f7b9d9e0af3bbf5052612d00a1787fa 100644 (file)
@@ -288,7 +288,6 @@ mt7915_regd_notifier(struct wiphy *wiphy,
        struct mt7915_dev *dev = mt7915_hw_dev(hw);
        struct mt76_phy *mphy = hw->priv;
        struct mt7915_phy *phy = mphy->priv;
-       struct cfg80211_chan_def *chandef = &mphy->chandef;
 
        memcpy(dev->mt76.alpha2, request->alpha2, sizeof(dev->mt76.alpha2));
        dev->mt76.region = request->dfs_region;
@@ -299,9 +298,7 @@ mt7915_regd_notifier(struct wiphy *wiphy,
        mt7915_init_txpower(dev, &mphy->sband_2g.sband);
        mt7915_init_txpower(dev, &mphy->sband_5g.sband);
 
-       if (!(chandef->chan->flags & IEEE80211_CHAN_RADAR))
-               return;
-
+       mphy->dfs_state = MT_DFS_STATE_UNKNOWN;
        mt7915_dfs_init_radar_detector(phy);
 }
 
@@ -976,8 +973,6 @@ int mt7915_register_device(struct mt7915_dev *dev)
 
        mt7915_init_wiphy(hw);
 
-       dev->phy.dfs_state = -1;
-
 #ifdef CONFIG_NL80211_TESTMODE
        dev->mt76.test_ops = &mt7915_testmode_ops;
 #endif
index 88bc4cf0dd79415a4ea5632dd29917554c82badf..59f0334ef8d23253868bc599659530644025cbad 100644 (file)
@@ -2439,41 +2439,48 @@ mt7915_dfs_init_radar_specs(struct mt7915_phy *phy)
 
 int mt7915_dfs_init_radar_detector(struct mt7915_phy *phy)
 {
-       struct cfg80211_chan_def *chandef = &phy->mt76->chandef;
        struct mt7915_dev *dev = phy->dev;
        bool ext_phy = phy != &dev->phy;
+       enum mt76_dfs_state dfs_state, prev_state;
        int err;
 
-       if (dev->mt76.region == NL80211_DFS_UNSET) {
-               phy->dfs_state = -1;
-               if (phy->rdd_state)
-                       goto stop;
+       prev_state = phy->mt76->dfs_state;
+       dfs_state = mt76_phy_dfs_state(phy->mt76);
 
+       if (prev_state == dfs_state)
                return 0;
-       }
 
-       if (test_bit(MT76_SCANNING, &phy->mt76->state))
-               return 0;
-
-       if (phy->dfs_state == chandef->chan->dfs_state)
-               return 0;
+       if (prev_state == MT_DFS_STATE_UNKNOWN)
+               mt7915_dfs_stop_radar_detector(phy);
 
-       err = mt7915_dfs_init_radar_specs(phy);
-       if (err < 0) {
-               phy->dfs_state = -1;
+       if (dfs_state == MT_DFS_STATE_DISABLED)
                goto stop;
-       }
 
-       phy->dfs_state = chandef->chan->dfs_state;
+       if (prev_state <= MT_DFS_STATE_DISABLED) {
+               err = mt7915_dfs_init_radar_specs(phy);
+               if (err < 0)
+                       return err;
+
+               err = mt7915_dfs_start_radar_detector(phy);
+               if (err < 0)
+                       return err;
 
-       if (chandef->chan->flags & IEEE80211_CHAN_RADAR) {
-               if (chandef->chan->dfs_state != NL80211_DFS_AVAILABLE)
-                       return mt7915_dfs_start_radar_detector(phy);
+               phy->mt76->dfs_state = MT_DFS_STATE_CAC;
+       }
+
+       if (dfs_state == MT_DFS_STATE_CAC)
+               return 0;
 
-               return mt76_connac_mcu_rdd_cmd(&dev->mt76, RDD_CAC_END,
-                                              ext_phy, MT_RX_SEL0, 0);
+       err = mt76_connac_mcu_rdd_cmd(&dev->mt76, RDD_CAC_END,
+                                     ext_phy, MT_RX_SEL0, 0);
+       if (err < 0) {
+               phy->mt76->dfs_state = MT_DFS_STATE_UNKNOWN;
+               return err;
        }
 
+       phy->mt76->dfs_state = MT_DFS_STATE_ACTIVE;
+       return 0;
+
 stop:
        err = mt76_connac_mcu_rdd_cmd(&dev->mt76, RDD_NORMAL_START, ext_phy,
                                      MT_RX_SEL0, 0);
@@ -2481,6 +2488,8 @@ stop:
                return err;
 
        mt7915_dfs_stop_radar_detector(phy);
+       phy->mt76->dfs_state = MT_DFS_STATE_DISABLED;
+
        return 0;
 }
 
index 989298ffffbcb3cc998621f91c4a5df60853badd..dee7fc011cdfaddf8c050ba2dac023108c77fe85 100644 (file)
@@ -302,26 +302,6 @@ static void mt7915_remove_interface(struct ieee80211_hw *hw,
        mt76_packet_id_flush(&dev->mt76, &msta->wcid);
 }
 
-static void mt7915_init_dfs_state(struct mt7915_phy *phy)
-{
-       struct mt76_phy *mphy = phy->mt76;
-       struct ieee80211_hw *hw = mphy->hw;
-       struct cfg80211_chan_def *chandef = &hw->conf.chandef;
-
-       if (hw->conf.flags & IEEE80211_CONF_OFFCHANNEL)
-               return;
-
-       if (!(chandef->chan->flags & IEEE80211_CHAN_RADAR) &&
-           !(mphy->chandef.chan->flags & IEEE80211_CHAN_RADAR))
-               return;
-
-       if (mphy->chandef.chan->center_freq == chandef->chan->center_freq &&
-           mphy->chandef.width == chandef->width)
-               return;
-
-       phy->dfs_state = -1;
-}
-
 int mt7915_set_channel(struct mt7915_phy *phy)
 {
        struct mt7915_dev *dev = phy->dev;
@@ -332,7 +312,6 @@ int mt7915_set_channel(struct mt7915_phy *phy)
        mutex_lock(&dev->mt76.mutex);
        set_bit(MT76_RESET, &phy->mt76->state);
 
-       mt7915_init_dfs_state(phy);
        mt76_set_channel(phy->mt76);
 
        if (dev->flash_mode) {
index e8c68e47b613b0859f78c67677210c44fe1e22a1..462c7da93b60db40fab75a8caba61e9435f4b1eb 100644 (file)
@@ -2786,7 +2786,7 @@ int mt7915_mcu_set_chan_info(struct mt7915_phy *phy, int cmd)
 
        if (phy->mt76->hw->conf.flags & IEEE80211_CONF_OFFCHANNEL)
                req.switch_reason = CH_SWITCH_SCAN_BYPASS_DPD;
-       else if ((chandef->chan->flags & IEEE80211_CHAN_RADAR) &&
+       else if (phy->mt76->hw->conf.radar_enabled &&
                 chandef->chan->dfs_state != NL80211_DFS_AVAILABLE)
                req.switch_reason = CH_SWITCH_DFS;
        else
index bc3a3dcdb3a051de1917b993affb1e50457e2313..96653d64d1618b8bcb17fb06c0aac0f2cee841bf 100644 (file)
@@ -230,7 +230,6 @@ struct mt7915_phy {
        u8 slottime;
 
        u8 rdd_state;
-       int dfs_state;
 
        u32 rx_ampdu_ts;
        u32 ampdu_ref;