ath11k: Reconfigure hardware rate for WCN6855 after vdev is started

There is an issue that WCN6855 tries to connect to an AP using
a hardware rate of 1Mb/s , even though the AP has announced
expected rates as [24, 36, 48, 54] in Probe Response frame.

The reason is that WCN6855 firmware clears hardware rate info
of management frames when vdev starts and uses 1Mb/s as default.
To solve it, reconfigure the rate after vdev is started.

Tested-on: WCN6855 hw2.0 PCI WLAN.HSP.1.1-01720.1-QCAHSPSWPL_V1_V2_SILICONZ_LITE-1
Signed-off-by: Baochen Qiang <quic_bqiang@quicinc.com>
Signed-off-by: Kalle Valo <quic_kvalo@quicinc.com>
Link: https://lore.kernel.org/r/20220112025400.2222-1-quic_bqiang@quicinc.com

drivers/net/wireless/ath/ath11k/core.h

@@ -603,6 +603,7 @@ struct ath11k {
 	struct completion finish_11d_ch_list;
 	bool pending_11d;
 	bool regdom_set_by_user;
+	int hw_rate_code;
 };
 
 struct ath11k_band_cap {

drivers/net/wireless/ath/ath11k/mac.c

@@ -2862,6 +2862,11 @@ static void ath11k_recalculate_mgmt_rate(struct ath11k *ar,
 	if (ret)
 		ath11k_warn(ar->ab, "failed to set mgmt tx rate %d\n", ret);
 
+	/* For WCN6855, firmware will clear this param when vdev starts, hence
+	 * cache it here so that we can reconfigure it once vdev starts.
+	 */
+	ar->hw_rate_code = hw_rate_code;
+
 	vdev_param = WMI_VDEV_PARAM_BEACON_RATE;
 	ret = ath11k_wmi_vdev_set_param_cmd(ar, arvif->vdev_id, vdev_param,
 					    hw_rate_code);
@@ -6960,6 +6965,19 @@ static int ath11k_start_vdev_delay(struct ieee80211_hw *hw,
 		return ret;
 	}
 
+	/* Reconfigure hardware rate code since it is cleared by firmware.
+	 */
+	if (ar->hw_rate_code > 0) {
+		u32 vdev_param = WMI_VDEV_PARAM_MGMT_RATE;
+
+		ret = ath11k_wmi_vdev_set_param_cmd(ar, arvif->vdev_id, vdev_param,
+						    ar->hw_rate_code);
+		if (ret) {
+			ath11k_warn(ar->ab, "failed to set mgmt tx rate %d\n", ret);
+			return ret;
+		}
+	}
+
 	if (arvif->vdev_type == WMI_VDEV_TYPE_MONITOR) {
 		ret = ath11k_wmi_vdev_up(ar, arvif->vdev_id, 0, ar->mac_addr);
 		if (ret) {