wifi: ath11k: Send 11d scan start before WMI_START_SCAN_CMDID

Firmwares advertising the support of triggering 11d algorithm on the
scan results of a regular scan expects driver to send
WMI_11D_SCAN_START_CMDID before sending WMI_START_SCAN_CMDID.
Triggering 11d algorithm on the scan results of a normal scan helps
in completely avoiding a separate 11d scan for determining regdomain.
This indirectly helps in speeding up connections on station
interfaces on the chipsets supporting 11D scan.

To enable this feature, send WMI_11D_SCAN_START_CMDID just before
sending WMI_START_SCAN_CMDID if the firmware advertises
WMI_TLV_SERVICE_SUPPORT_11D_FOR_HOST_SCAN service flag.

WCN6750 & WCN6855 supports this feature.

Tested-on: WCN6750 hw1.0 AHB WLAN.MSL.1.0.1-01160-QCAMSLSWPLZ-1
Tested-on: WCN6855 hw2.1 PCI WLAN.HSP.1.1-03125-QCAHSPSWPL_V1_V2_SILICONZ_LITE-3.6510.23
Signed-off-by: Manikanta Pubbisetty <quic_mpubbise@quicinc.com>
Signed-off-by: Kalle Valo <quic_kvalo@quicinc.com>
Link: https://lore.kernel.org/r/20230315161817.29627-1-quic_mpubbise@quicinc.com

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

@@ -3755,6 +3755,18 @@ static int ath11k_mac_op_hw_scan(struct ieee80211_hw *hw,
 	int i;
 	u32 scan_timeout;
 
+	/* Firmwares advertising the support of triggering 11D algorithm
+	 * on the scan results of a regular scan expects driver to send
+	 * WMI_11D_SCAN_START_CMDID before sending WMI_START_SCAN_CMDID.
+	 * With this feature, separate 11D scan can be avoided since
+	 * regdomain can be determined with the scan results of the
+	 * regular scan.
+	 */
+	if (ar->state_11d == ATH11K_11D_PREPARING &&
+	    test_bit(WMI_TLV_SERVICE_SUPPORT_11D_FOR_HOST_SCAN,
+		     ar->ab->wmi_ab.svc_map))
+		ath11k_mac_11d_scan_start(ar, arvif->vdev_id);
+
 	mutex_lock(&ar->conf_mutex);
 
 	spin_lock_bh(&ar->data_lock);

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

@@ -2103,6 +2103,7 @@ enum wmi_tlv_service {
 	WMI_TLV_SERVICE_SCAN_CONFIG_PER_CHANNEL = 265,
 	WMI_TLV_SERVICE_REG_CC_EXT_EVENT_SUPPORT = 281,
 	WMI_TLV_SERVICE_BIOS_SAR_SUPPORT = 326,
+	WMI_TLV_SERVICE_SUPPORT_11D_FOR_HOST_SCAN = 357,
 
 	/* The third 128 bits */
 	WMI_MAX_EXT2_SERVICE = 384