Revert "wifi: cfg80211: fix CQM for non-range use"

This reverts commit 307a652 which is
commit 7e7efdd upstream.

It needed to have commit 076fc87 ("wifi: cfg80211: remove wdev
mutex") applied to properly work, otherwise regressions happen.

Link: https://lore.kernel.org/r/e374bb16-5b13-44cc-b11a-2f4eefb1ecf5@manjaro.org
Link: https://lore.kernel.org/r/87sf4belmm.fsf@turtle.gmx.de
Link: https://lore.kernel.org/r/20231210213930.61378-1-leo@leolam.fr
Reported-by: Léo Lam <leo@leolam.fr>
Reported-by: Sven Joachim <svenjoac@gmx.de>
Reported-by: Philip Müller <philm@manjaro.org>
Cc: Johannes Berg <johannes.berg@intel.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

net/wireless/core.h

@@ -297,7 +297,6 @@ struct cfg80211_cqm_config {
 	u32 rssi_hyst;
 	s32 last_rssi_event_value;
 	enum nl80211_cqm_rssi_threshold_event last_rssi_event_type;
-	bool use_range_api;
 	int n_rssi_thresholds;
 	s32 rssi_thresholds[];
 };

net/wireless/nl80211.c

@@ -12574,6 +12574,10 @@ static int cfg80211_cqm_rssi_update(struct cfg80211_registered_device *rdev,
 	int i, n, low_index;
 	int err;
 
+	/* RSSI reporting disabled? */
+	if (!cqm_config)
+		return rdev_set_cqm_rssi_range_config(rdev, dev, 0, 0);
+
 	/*
 	 * Obtain current RSSI value if possible, if not and no RSSI threshold
 	 * event has been received yet, we should receive an event after a
@@ -12648,27 +12652,25 @@ static int nl80211_set_cqm_rssi(struct genl_info *info,
 	    wdev->iftype != NL80211_IFTYPE_P2P_CLIENT)
 		return -EOPNOTSUPP;
 
+	if (n_thresholds <= 1 && rdev->ops->set_cqm_rssi_config) {
+		if (n_thresholds == 0 || thresholds[0] == 0) /* Disabling */
+			return rdev_set_cqm_rssi_config(rdev, dev, 0, 0);
+
+		return rdev_set_cqm_rssi_config(rdev, dev,
+						thresholds[0], hysteresis);
+	}
+
+	if (!wiphy_ext_feature_isset(&rdev->wiphy,
+				     NL80211_EXT_FEATURE_CQM_RSSI_LIST))
+		return -EOPNOTSUPP;
+
 	if (n_thresholds == 1 && thresholds[0] == 0) /* Disabling */
 		n_thresholds = 0;
 
 	wdev_lock(wdev);
 	old = rcu_dereference_protected(wdev->cqm_config,
 					lockdep_is_held(&wdev->mtx));
 
-	/* if already disabled just succeed */
-	if (!n_thresholds && !old)
-		return 0;
-
-	if (n_thresholds > 1) {
-		if (!wiphy_ext_feature_isset(&rdev->wiphy,
-					     NL80211_EXT_FEATURE_CQM_RSSI_LIST) ||
-		    !rdev->ops->set_cqm_rssi_range_config)
-			return -EOPNOTSUPP;
-	} else {
-		if (!rdev->ops->set_cqm_rssi_config)
-			return -EOPNOTSUPP;
-	}
-
 	if (n_thresholds) {
 		cqm_config = kzalloc(struct_size(cqm_config, rssi_thresholds,
 						 n_thresholds),
@@ -12683,26 +12685,13 @@ static int nl80211_set_cqm_rssi(struct genl_info *info,
 		memcpy(cqm_config->rssi_thresholds, thresholds,
 		       flex_array_size(cqm_config, rssi_thresholds,
 				       n_thresholds));
-		cqm_config->use_range_api = n_thresholds > 1 ||
-					    !rdev->ops->set_cqm_rssi_config;
 
 		rcu_assign_pointer(wdev->cqm_config, cqm_config);
-
-		if (cqm_config->use_range_api)
-			err = cfg80211_cqm_rssi_update(rdev, dev, cqm_config);
-		else
-			err = rdev_set_cqm_rssi_config(rdev, dev,
-						       thresholds[0],
-						       hysteresis);
 	} else {
 		RCU_INIT_POINTER(wdev->cqm_config, NULL);
-		/* if enabled as range also disable via range */
-		if (old->use_range_api)
-			err = rdev_set_cqm_rssi_range_config(rdev, dev, 0, 0);
-		else
-			err = rdev_set_cqm_rssi_config(rdev, dev, 0, 0);
 	}
 
+	err = cfg80211_cqm_rssi_update(rdev, dev, cqm_config);
 	if (err) {
 		rcu_assign_pointer(wdev->cqm_config, old);
 		kfree_rcu(cqm_config, rcu_head);
@@ -18769,11 +18758,10 @@ void cfg80211_cqm_rssi_notify_work(struct wiphy *wiphy, struct wiphy_work *work)
 	wdev_lock(wdev);
 	cqm_config = rcu_dereference_protected(wdev->cqm_config,
 					       lockdep_is_held(&wdev->mtx));
-	if (!cqm_config)
+	if (!wdev->cqm_config)
 		goto unlock;
 
-	if (cqm_config->use_range_api)
-		cfg80211_cqm_rssi_update(rdev, wdev->netdev, cqm_config);
+	cfg80211_cqm_rssi_update(rdev, wdev->netdev, cqm_config);
 
 	rssi_level = cqm_config->last_rssi_event_value;
 	rssi_event = cqm_config->last_rssi_event_type;