qcacld-3.0: Update valid rssi value to upper-layer

For a small window during roaming and new connection, there is a
possibility of firmware to send the invalid rssi value(other than
0-127), leading driver to send the same invalid rssi value to upper-layer.

To mitigate this issue:
1) Either send previous valid rssi value to upper-layer on receiving invalid
   rssi value from the firmware.
2) Or if previous rssi value is not valid, fetch rssi value from beacon frame
   of connected AP from scan cache.

Change-Id: I4443ed06cd80826ff386c2b4a536a2dc1a1e0881
CRs-Fixed: 2042747

core/hdd/inc/wlan_hdd_main.h

@@ -2475,4 +2475,16 @@ void hdd_chip_pwr_save_fail_detected_cb(void *hddctx,
 				struct chip_pwr_save_fail_detected_params
 				*data);
 
+/**
+ * hdd_get_rssi_snr_by_bssid() - gets the rssi and snr by bssid from scan cache
+ * @adapter: adapter handle
+ * @bssid: bssid to look for in scan cache
+ * @rssi: rssi value found
+ * @snr: snr value found
+ *
+ * Return: QDF_STATUS
+ */
+int hdd_get_rssi_snr_by_bssid(hdd_adapter_t *adapter, const uint8_t *bssid,
+			      int8_t *rssi, int8_t *snr);
+
 #endif /* end #if !defined(WLAN_HDD_MAIN_H) */

core/hdd/src/wlan_hdd_main.c

@@ -12050,6 +12050,23 @@ hdd_adapter_t *wlan_hdd_get_adapter_from_vdev(struct wlan_objmgr_psoc
 	return adapter;
 }
 
+int hdd_get_rssi_snr_by_bssid(hdd_adapter_t *adapter, const uint8_t *bssid,
+			      int8_t *rssi, int8_t *snr)
+{
+	QDF_STATUS status;
+	hdd_wext_state_t *wext_state = WLAN_HDD_GET_WEXT_STATE_PTR(adapter);
+	tCsrRoamProfile *profile = &wext_state->roamProfile;
+
+	status = sme_get_rssi_snr_by_bssid(WLAN_HDD_GET_HAL_CTX(adapter),
+				profile, bssid, rssi, snr);
+	if (QDF_STATUS_SUCCESS != status) {
+		hdd_warn("sme_get_rssi_snr_by_bssid failed");
+		return -EINVAL;
+	}
+
+	return 0;
+}
+
 /* Register the module init/exit functions */
 module_init(hdd_module_init);
 module_exit(hdd_module_exit);

core/hdd/src/wlan_hdd_stats.c

@@ -3093,7 +3093,18 @@ static int __wlan_hdd_cfg80211_get_station(struct wiphy *wiphy,
 		return status;
 
 	wlan_hdd_get_station_stats(pAdapter);
-	sinfo->signal = pAdapter->hdd_stats.summary_stat.rssi;
+
+	if (pAdapter->hdd_stats.summary_stat.rssi)
+		pAdapter->rssi = pAdapter->hdd_stats.summary_stat.rssi;
+
+	/* for new connection there might be no valid previous RSSI */
+	if (!pAdapter->rssi) {
+		hdd_get_rssi_snr_by_bssid(pAdapter,
+				pHddStaCtx->conn_info.bssId.bytes,
+				&pAdapter->rssi, NULL);
+	}
+
+	sinfo->signal = pAdapter->rssi;
 	snr = pAdapter->hdd_stats.summary_stat.snr;
 	hdd_debug("snr: %d, rssi: %d",
 		pAdapter->hdd_stats.summary_stat.snr,

core/hdd/src/wlan_hdd_wext.c

@@ -3595,9 +3595,22 @@ QDF_STATUS wlan_hdd_get_rssi(hdd_adapter_t *pAdapter, int8_t *rssi_value)
 		} else {
 			/* update the adapter with the fresh results */
 			priv = hdd_request_priv(request);
-			pAdapter->rssi = priv->rssi;
-			if (pAdapter->rssi > 0)
-				pAdapter->rssi = 0;
+			/*
+			 * update rssi only if its valid else return previous
+			 * valid rssi.
+			 */
+			if (priv->rssi)
+				pAdapter->rssi = priv->rssi;
+
+			/*
+			 * for new connection there might be no valid previous
+			 * RSSI.
+			 */
+			if (!pAdapter->rssi) {
+				hdd_get_rssi_snr_by_bssid(pAdapter,
+					pHddStaCtx->conn_info.bssId.bytes,
+					&pAdapter->rssi, NULL);
+			}
 		}
 	}
 

core/sme/inc/sme_api.h

@@ -1449,6 +1449,20 @@ QDF_STATUS sme_set_wow_pulse(struct wow_pulse_mode *wow_pulse_set_info);
 void sme_set_chan_info_callback(tHalHandle hal_handle,
 			void (*callback)(struct scan_chan_info *chan_info));
 
+/**
+ * sme_get_rssi_snr_by_bssid() - gets the rssi and snr by bssid from scan cache
+ * @hal: handle returned by mac_open
+ * @profile: current connected profile
+ * @bssid: bssid to look for in scan cache
+ * @rssi: rssi value found
+ * @snr: snr value found
+ *
+ * Return: QDF_STATUS
+ */
+QDF_STATUS sme_get_rssi_snr_by_bssid(tHalHandle hal, tCsrRoamProfile *profile,
+				     const uint8_t *bssid, int8_t *rssi,
+				     int8_t *snr);
+
 /**
  * sme_get_beacon_frm() - gets the bss descriptor from scan cache and prepares
  * beacon frame

core/sme/src/common/sme_api.c

@@ -15919,6 +15919,82 @@ static void sme_prepare_beacon_from_bss_descp(uint8_t *frame_buf,
 		     &bss_descp->ieFields, ie_len);
 }
 
+QDF_STATUS sme_get_rssi_snr_by_bssid(tHalHandle hal,
+				tCsrRoamProfile *profile,
+				const uint8_t *bssid,
+				int8_t *rssi, int8_t *snr)
+{
+	tSirBssDescription *bss_descp;
+	tCsrScanResultFilter *scan_filter;
+	struct scan_result_list *bss_list;
+	tScanResultHandle result_handle = NULL;
+	QDF_STATUS status = QDF_STATUS_SUCCESS;
+	tpAniSirGlobal mac_ctx = PMAC_STRUCT(hal);
+
+	scan_filter = qdf_mem_malloc(sizeof(tCsrScanResultFilter));
+	if (NULL == scan_filter) {
+		sme_err("memory allocation failed");
+		status = QDF_STATUS_E_NOMEM;
+		goto free_scan_flter;
+	}
+
+	status = csr_roam_prepare_filter_from_profile(mac_ctx,
+						profile, scan_filter);
+	if (QDF_STATUS_SUCCESS != status) {
+		sme_err("prepare_filter failed");
+		goto free_scan_flter;
+	}
+
+	/* update filter to get scan result with just target BSSID */
+	if (NULL == scan_filter->BSSIDs.bssid) {
+		scan_filter->BSSIDs.bssid =
+			qdf_mem_malloc(sizeof(struct qdf_mac_addr));
+		if (scan_filter->BSSIDs.bssid == NULL) {
+			sme_err("malloc failed");
+			status = QDF_STATUS_E_NOMEM;
+			goto free_scan_flter;
+		}
+	}
+
+	scan_filter->BSSIDs.numOfBSSIDs = 1;
+	qdf_mem_copy(scan_filter->BSSIDs.bssid[0].bytes,
+		     bssid, sizeof(struct qdf_mac_addr));
+
+	status = csr_scan_get_result(mac_ctx, scan_filter, &result_handle);
+	if (QDF_STATUS_SUCCESS != status) {
+		sme_err("parse_scan_result failed");
+		goto free_scan_flter;
+	}
+
+	bss_list = (struct scan_result_list *)result_handle;
+	bss_descp = csr_get_fst_bssdescr_ptr(bss_list);
+	if (!bss_descp) {
+		sme_err("unable to fetch bss descriptor");
+		status = QDF_STATUS_E_FAULT;
+		goto free_scan_flter;
+	}
+
+	sme_debug("snr: %d, rssi: %d, raw_rssi: %d",
+		bss_descp->sinr, bss_descp->rssi, bss_descp->rssi_raw);
+
+	if (rssi)
+		*rssi = bss_descp->rssi;
+	if (snr)
+		*snr = bss_descp->sinr;
+
+free_scan_flter:
+	/* free scan filter and exit */
+	if (scan_filter) {
+		csr_free_scan_filter(mac_ctx, scan_filter);
+		qdf_mem_free(scan_filter);
+	}
+
+	if (result_handle)
+		csr_scan_result_purge(mac_ctx, result_handle);
+
+	return status;
+}
+
 QDF_STATUS sme_get_beacon_frm(tHalHandle hal, tCsrRoamProfile *profile,
 				const tSirMacAddr bssid,
 				uint8_t **frame_buf, uint32_t *frame_len,

core/wma/inc/wma.h

@@ -276,8 +276,10 @@ enum ds_mode {
  * But, to maintain backward compatibility, the old
  * value is also preserved.
  */
-#define WMA_TGT_INVALID_SNR_OLD (-1)
-#define WMA_TGT_INVALID_SNR_NEW 0x127
+#define WMA_TGT_INVALID_SNR (0)
+
+#define WMA_TGT_IS_VALID_SNR(x)  (((x) >= 0 && (x) < 0x7f) ? true : false)
+#define WMA_TGT_IS_INVALID_SNR(x) (!WMA_TGT_IS_VALID_SNR(x))
 
 #define WMA_TX_Q_RECHECK_TIMER_WAIT      2      /* 2 ms */
 #define WMA_TX_Q_RECHECK_TIMER_MAX_WAIT  20     /* 20 ms */

core/wma/src/wma_utils.c

@@ -2273,14 +2273,13 @@ static void wma_vdev_stats_lost_link_helper(tp_wma_handle wma,
 		dat_snr = vdev_stats->vdev_snr.dat_snr;
 		WMA_LOGD(FL("get vdev id %d, beancon snr %d, data snr %d"),
 			vdev_stats->vdev_id, bcn_snr, dat_snr);
-		if ((bcn_snr != WMA_TGT_INVALID_SNR_OLD) &&
-			(bcn_snr != WMA_TGT_INVALID_SNR_NEW))
+
+		if (WMA_TGT_IS_VALID_SNR(bcn_snr))
 			rssi = bcn_snr;
-		else if ((dat_snr != WMA_TGT_INVALID_SNR_OLD) &&
-			(dat_snr != WMA_TGT_INVALID_SNR_NEW))
+		else if (WMA_TGT_IS_VALID_SNR(dat_snr))
 			rssi = dat_snr;
 		else
-			rssi = WMA_TGT_INVALID_SNR_OLD;
+			rssi = WMA_TGT_INVALID_SNR;
 
 		/* Get the absolute rssi value from the current rssi value */
 		rssi = rssi + WMA_TGT_NOISE_FLOOR_DBM;
@@ -2340,28 +2339,29 @@ static void wma_update_vdev_stats(tp_wma_handle wma,
 			summary_stats->rts_succ_cnt = vdev_stats->rts_succ_cnt;
 			summary_stats->rts_fail_cnt = vdev_stats->rts_fail_cnt;
 			/* Update SNR and RSSI in SummaryStats */
-			if ((bcn_snr != WMA_TGT_INVALID_SNR_OLD) &&
-				(bcn_snr != WMA_TGT_INVALID_SNR_NEW)) {
+			if (WMA_TGT_IS_VALID_SNR(bcn_snr)) {
 				summary_stats->snr = bcn_snr;
 				summary_stats->rssi =
 					bcn_snr + WMA_TGT_NOISE_FLOOR_DBM;
-			} else if ((dat_snr != WMA_TGT_INVALID_SNR_OLD) &&
-					(dat_snr != WMA_TGT_INVALID_SNR_NEW)) {
+			} else if (WMA_TGT_IS_VALID_SNR(dat_snr)) {
 				summary_stats->snr = dat_snr;
 				summary_stats->rssi =
 					bcn_snr + WMA_TGT_NOISE_FLOOR_DBM;
 			} else {
-				summary_stats->snr = WMA_TGT_INVALID_SNR_OLD;
+				summary_stats->snr = WMA_TGT_INVALID_SNR;
 				summary_stats->rssi = 0;
 			}
 		}
 	}
 
 	if (pGetRssiReq && pGetRssiReq->sessionId == vdev_stats->vdev_id) {
-		if ((bcn_snr == WMA_TGT_INVALID_SNR_OLD ||
-				bcn_snr == WMA_TGT_INVALID_SNR_NEW) &&
-				(dat_snr == WMA_TGT_INVALID_SNR_OLD ||
-				  dat_snr == WMA_TGT_INVALID_SNR_NEW)) {
+		if (WMA_TGT_IS_VALID_SNR(bcn_snr)) {
+			rssi = bcn_snr;
+			rssi = rssi + WMA_TGT_NOISE_FLOOR_DBM;
+		} else if (WMA_TGT_IS_VALID_SNR(dat_snr)) {
+			rssi = dat_snr;
+			rssi = rssi + WMA_TGT_NOISE_FLOOR_DBM;
+		} else {
 			/*
 			 * Firmware sends invalid snr till it sees
 			 * Beacon/Data after connection since after
@@ -2370,21 +2370,6 @@ static void wma_update_vdev_stats(tp_wma_handle wma,
 			 * rssi during connection.
 			 */
 			WMA_LOGE("Invalid SNR from firmware");
-
-		} else {
-			if (bcn_snr != WMA_TGT_INVALID_SNR_OLD &&
-				bcn_snr != WMA_TGT_INVALID_SNR_NEW) {
-				rssi = bcn_snr;
-			} else if (dat_snr != WMA_TGT_INVALID_SNR_OLD &&
-				dat_snr != WMA_TGT_INVALID_SNR_NEW) {
-				rssi = dat_snr;
-			}
-
-			/*
-			 * Get the absolute rssi value from current rssi value
-			 * the sinr value is hardcoded into 0 in the core stack
-			 */
-			rssi = rssi + WMA_TGT_NOISE_FLOOR_DBM;
 		}
 
 		WMA_LOGD("Average Rssi = %d, vdev id= %d", rssi,
@@ -2404,14 +2389,12 @@ static void wma_update_vdev_stats(tp_wma_handle wma,
 	if (node->psnr_req) {
 		tAniGetSnrReq *p_snr_req = node->psnr_req;
 
-		if ((bcn_snr != WMA_TGT_INVALID_SNR_OLD) &&
-			(bcn_snr != WMA_TGT_INVALID_SNR_NEW))
+		if (WMA_TGT_IS_VALID_SNR(bcn_snr))
 			p_snr_req->snr = bcn_snr;
-		else if ((dat_snr != WMA_TGT_INVALID_SNR_OLD) &&
-				(dat_snr != WMA_TGT_INVALID_SNR_NEW))
+		else if (WMA_TGT_IS_VALID_SNR(dat_snr))
 			p_snr_req->snr = dat_snr;
 		else
-			p_snr_req->snr = WMA_TGT_INVALID_SNR_OLD;
+			p_snr_req->snr = WMA_TGT_INVALID_SNR;
 
 		sme_msg.type = eWNI_SME_SNR_IND;
 		sme_msg.bodyptr = p_snr_req;
@@ -2551,12 +2534,10 @@ static void wma_update_per_chain_rssi_stats(tp_wma_handle wma,
 		dat_snr = rssi_stats->rssi_avg_data[i];
 		WMA_LOGD("chain %d beacon snr %d data snr %d",
 			i, bcn_snr, dat_snr);
-		if ((dat_snr != WMA_TGT_INVALID_SNR_OLD) &&
-			(dat_snr != WMA_TGT_INVALID_SNR_NEW))
-			rssi_per_chain_stats->rssi[i] = dat_snr;
-		else if ((bcn_snr != WMA_TGT_INVALID_SNR_OLD) &&
-			(bcn_snr != WMA_TGT_INVALID_SNR_NEW))
+		if (WMA_TGT_IS_VALID_SNR(bcn_snr))
 			rssi_per_chain_stats->rssi[i] = bcn_snr;
+		else if (WMA_TGT_IS_VALID_SNR(dat_snr))
+			rssi_per_chain_stats->rssi[i] = dat_snr;
 		else
 			/*
 			 * Firmware sends invalid snr till it sees
@@ -2565,7 +2546,7 @@ static void wma_update_per_chain_rssi_stats(tp_wma_handle wma,
 			 * In this duartion Host will return an invalid rssi
 			 * value.
 			 */
-			rssi_per_chain_stats->rssi[i] = WMA_TGT_RSSI_INVALID;
+			rssi_per_chain_stats->rssi[i] = WMA_TGT_INVALID_SNR;
 
 		/*
 		 * Get the absolute rssi value from the current rssi value the