wifi: iwlwifi: mvm: record and return channel survey information

While doing a passive scan, the firmware will report per-channel survey
information. This information is primarily useful for hostapd when doing
an ACS (Automatic Channel Selection). Collect this information and add
it to the result set when getting the survey information.

Signed-off-by: Benjamin Berg <benjamin.berg@intel.com>
Signed-off-by: Miri Korenblit <miriam.rachel.korenblit@intel.com>
Link: https://msgid.link/20240506095953.9287591a5999.I54a3f9f6480d3694e67eea1cb4f5853beace2780@changeid
Signed-off-by: Johannes Berg <johannes.berg@intel.com>

1 files changed, 67 insertions, 4 deletions

diff --git a/drivers/net/wireless/intel/iwlwifi/mvm/mac80211.c b/drivers/net/wireless/intel/iwlwifi/mvm/mac80211.c
index fb49deda3346..486a6b8f3c97 100644
--- a/drivers/net/wireless/intel/iwlwifi/mvm/mac80211.c
+++ b/drivers/net/wireless/intel/iwlwifi/mvm/mac80211.c
@@ -5899,6 +5899,65 @@ void iwl_mvm_mac_flush_sta(struct ieee80211_hw *hw, struct ieee80211_vif *vif,
 	mutex_unlock(&mvm->mutex);
 }
 
+static int iwl_mvm_mac_get_acs_survey(struct iwl_mvm *mvm, int idx,
+				      struct survey_info *survey)
+{
+	int chan_idx;
+	enum nl80211_band band;
+	int ret;
+
+	mutex_lock(&mvm->mutex);
+
+	if (!mvm->acs_survey) {
+		ret = -ENOENT;
+		goto out;
+	}
+
+	/* Find and return the next entry that has a non-zero active time */
+	for (band = 0; band < NUM_NL80211_BANDS; band++) {
+		struct ieee80211_supported_band *sband =
+			mvm->hw->wiphy->bands[band];
+
+		if (!sband)
+			continue;
+
+		for (chan_idx = 0; chan_idx < sband->n_channels; chan_idx++) {
+			struct iwl_mvm_acs_survey_channel *info =
+				&mvm->acs_survey->bands[band][chan_idx];
+
+			if (!info->time)
+				continue;
+
+			/* Found (the next) channel to report */
+			survey->channel = &sband->channels[chan_idx];
+			survey->filled = SURVEY_INFO_TIME |
+					 SURVEY_INFO_TIME_BUSY |
+					 SURVEY_INFO_TIME_RX |
+					 SURVEY_INFO_TIME_TX;
+			survey->time = info->time;
+			survey->time_busy = info->time_busy;
+			survey->time_rx = info->time_rx;
+			survey->time_tx = info->time_tx;
+			survey->noise = info->noise;
+			if (survey->noise < 0)
+				survey->filled |= SURVEY_INFO_NOISE_DBM;
+
+			/* Clear time so that channel is only reported once */
+			info->time = 0;
+
+			ret = 0;
+			goto out;
+		}
+	}
+
+	ret = -ENOENT;
+
+out:
+	mutex_unlock(&mvm->mutex);
+
+	return ret;
+}
+
 int iwl_mvm_mac_get_survey(struct ieee80211_hw *hw, int idx,
 			   struct survey_info *survey)
 {
@@ -5911,14 +5970,18 @@ int iwl_mvm_mac_get_survey(struct ieee80211_hw *hw, int idx,
 
 	memset(survey, 0, sizeof(*survey));
 
-	/* only support global statistics right now */
-	if (idx != 0)
-		return -ENOENT;
-
 	if (!fw_has_capa(&mvm->fw->ucode_capa,
 			 IWL_UCODE_TLV_CAPA_RADIO_BEACON_STATS))
 		return -ENOENT;
 
+	/*
+	 * Return the beacon stats at index zero and pass on following indices
+	 * to the function returning the full survey, most likely for ACS
+	 * (Automatic Channel Selection).
+	 */
+	if (idx > 0)
+		return iwl_mvm_mac_get_acs_survey(mvm, idx - 1, survey);
+
 	mutex_lock(&mvm->mutex);
 
 	if (iwl_mvm_firmware_running(mvm)) {