ath6kl: support rssi threshold for sched scan

The ath6kl firmware can filter scan results based on rssi. This is
useful to limit hosts wakeups on scheduled scans.
Signed-off-by: Thomas Pedersen <c_tpeder@qca.qualcomm.com>
Signed-off-by: Kalle Valo <kvalo@qca.qualcomm.com>

drivers/net/wireless/ath/ath6kl/cfg80211.c

@@ -3211,7 +3211,7 @@ static int ath6kl_cfg80211_sscan_start(struct wiphy *wiphy,
 	struct ath6kl *ar = ath6kl_priv(dev);
 	struct ath6kl_vif *vif = netdev_priv(dev);
 	u16 interval;
-	int ret;
+	int ret, rssi_thold;
 
 	if (ar->state != ATH6KL_STATE_ON)
 		return -EIO;
@@ -3244,6 +3244,23 @@ static int ath6kl_cfg80211_sscan_start(struct wiphy *wiphy,
 			return ret;
 	}
 
+	if (test_bit(ATH6KL_FW_CAPABILITY_RSSI_SCAN_THOLD,
+		     ar->fw_capabilities)) {
+		if (request->rssi_thold <= NL80211_SCAN_RSSI_THOLD_OFF)
+			rssi_thold = 0;
+		else if (request->rssi_thold < -127)
+			rssi_thold = -127;
+		else
+			rssi_thold = request->rssi_thold;
+
+		ret = ath6kl_wmi_set_rssi_filter_cmd(ar->wmi, vif->fw_vif_idx,
+						     rssi_thold);
+		if (ret) {
+			ath6kl_err("failed to set RSSI threshold for scan\n");
+			return ret;
+		}
+	}
+
 	/* fw uses seconds, also make sure that it's >0 */
 	interval = max_t(u16, 1, request->interval / 1000);
 

drivers/net/wireless/ath/ath6kl/core.h

@@ -115,6 +115,9 @@ enum ath6kl_fw_capability {
 	 */
 	ATH6KL_FW_CAPABILITY_SCHED_SCAN_MATCH_LIST,
 
+	/* Firmware supports filtering BSS results by RSSI */
+	ATH6KL_FW_CAPABILITY_RSSI_SCAN_THOLD,
+
 	/* this needs to be last */
 	ATH6KL_FW_CAPABILITY_MAX,
 };

drivers/net/wireless/ath/ath6kl/wmi.c

@@ -1531,6 +1531,24 @@ static int ath6kl_wmi_cac_event_rx(struct wmi *wmi, u8 *datap, int len,
 	return 0;
 }
 
+int ath6kl_wmi_set_rssi_filter_cmd(struct wmi *wmi, u8 if_idx, s8 rssi)
+{
+	struct sk_buff *skb;
+	struct wmi_set_rssi_filter_cmd *cmd;
+	int ret;
+
+	skb = ath6kl_wmi_get_new_buf(sizeof(*cmd));
+	if (!skb)
+		return -ENOMEM;
+
+	cmd = (struct wmi_set_rssi_filter_cmd *) skb->data;
+	cmd->rssi = rssi;
+
+	ret = ath6kl_wmi_cmd_send(wmi, if_idx, skb, WMI_SET_RSSI_FILTER_CMDID,
+				  NO_SYNC_WMIFLAG);
+	return ret;
+}
+
 static int ath6kl_wmi_send_snr_threshold_params(struct wmi *wmi,
 			struct wmi_snr_threshold_params_cmd *snr_cmd)
 {

drivers/net/wireless/ath/ath6kl/wmi.h

@@ -628,6 +628,10 @@ enum wmi_cmd_id {
 	WMI_SET_MCASTRATE,
 
 	WMI_STA_BMISS_ENHANCE_CMDID,
+
+	WMI_SET_REGDOMAIN_CMDID,
+
+	WMI_SET_RSSI_FILTER_CMDID,
 };
 
 enum wmi_mgmt_frame_type {
@@ -1276,6 +1280,11 @@ struct wmi_snr_threshold_params_cmd {
 	u8 reserved[3];
 } __packed;
 
+/* Don't report BSSs with signal (RSSI) below this threshold */
+struct wmi_set_rssi_filter_cmd {
+	s8 rssi;
+} __packed;
+
 enum wmi_preamble_policy {
 	WMI_IGNORE_BARKER_IN_ERP = 0,
 	WMI_FOLLOW_BARKER_IN_ERP,
@@ -2592,6 +2601,7 @@ int ath6kl_wmi_add_wow_pattern_cmd(struct wmi *wmi, u8 if_idx,
 				   const u8 *mask);
 int ath6kl_wmi_del_wow_pattern_cmd(struct wmi *wmi, u8 if_idx,
 				   u16 list_id, u16 filter_id);
+int ath6kl_wmi_set_rssi_filter_cmd(struct wmi *wmi, u8 if_idx, s8 rssi);
 int ath6kl_wmi_set_roam_lrssi_cmd(struct wmi *wmi, u8 lrssi);
 int ath6kl_wmi_ap_set_dtim_cmd(struct wmi *wmi, u8 if_idx, u32 dtim_period);
 int ath6kl_wmi_force_roam_cmd(struct wmi *wmi, const u8 *bssid);