ath6kl: use custom MAC address for newly created interfaces

Firmware and driver generate MAC addresses for the second and third interfaces.
In addition to the existing algorithm, flip bit 7 of 5th octet. Since both
firmware and driver individually generate the MAC addresses, introduce a new
firmware capability bit to keep them compatible.
Signed-off-by: Aarthi Thiruvengadam <athiruve@qca.qualcomm.com>
Signed-off-by: Kalle Valo <kvalo@qca.qualcomm.com>

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

@@ -3523,9 +3523,13 @@ struct wireless_dev *ath6kl_interface_add(struct ath6kl *ar, const char *name,
 	vif->htcap[IEEE80211_BAND_5GHZ].ht_enable = true;
 
 	memcpy(ndev->dev_addr, ar->mac_addr, ETH_ALEN);
-	if (fw_vif_idx != 0)
+	if (fw_vif_idx != 0) {
 		ndev->dev_addr[0] = (ndev->dev_addr[0] ^ (1 << fw_vif_idx)) |
 				     0x2;
+		if (test_bit(ATH6KL_FW_CAPABILITY_CUSTOM_MAC_ADDR,
+			     ar->fw_capabilities))
+			ndev->dev_addr[4] ^= 0x80;
+	}
 
 	init_netdev(ndev);
 

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

@@ -118,6 +118,9 @@ enum ath6kl_fw_capability {
 	/* Firmware supports filtering BSS results by RSSI */
 	ATH6KL_FW_CAPABILITY_RSSI_SCAN_THOLD,
 
+	/* FW sets mac_addr[4] ^= 0x80 for newly created interfaces */
+	ATH6KL_FW_CAPABILITY_CUSTOM_MAC_ADDR,
+
 	/* this needs to be last */
 	ATH6KL_FW_CAPABILITY_MAX,
 };