ath6kl: add support for changing contry code

To make it possible to change the country code from user space via nl80211
add handler for reg_notifier. The feature is only enabled when built
time option CONFIG_ATH6KL_REGDOMAIN is enabled, which again depends on
CFG80211_CERTIFICATION_ONUS for certication purposes.

Signed-off-by: Kalle Valo <kvalo@qca.qualcomm.com>
diff --git a/drivers/net/wireless/ath/ath6kl/cfg80211.c b/drivers/net/wireless/ath/ath6kl/cfg80211.c
index 4f538f0..f620af5 100644
--- a/drivers/net/wireless/ath/ath6kl/cfg80211.c
+++ b/drivers/net/wireless/ath/ath6kl/cfg80211.c
@@ -3458,6 +3458,49 @@
 		ath6kl_cfg80211_stop(vif);
 }
 
+static int ath6kl_cfg80211_reg_notify(struct wiphy *wiphy,
+				      struct regulatory_request *request)
+{
+	struct ath6kl *ar = wiphy_priv(wiphy);
+	u32 rates[IEEE80211_NUM_BANDS];
+	int ret, i;
+
+	ath6kl_dbg(ATH6KL_DBG_WLAN_CFG,
+		   "cfg reg_notify %c%c%s%s initiator %d\n",
+		   request->alpha2[0], request->alpha2[1],
+		   request->intersect ? " intersect" : "",
+		   request->processed ? " processed" : "",
+		   request->initiator);
+
+	ret = ath6kl_wmi_set_regdomain_cmd(ar->wmi, request->alpha2);
+	if (ret) {
+		ath6kl_err("failed to set regdomain: %d\n", ret);
+		return ret;
+	}
+
+	/*
+	 * Firmware will apply the regdomain change only after a scan is
+	 * issued and it will send a WMI_REGDOMAIN_EVENTID when it has been
+	 * changed.
+	 */
+
+	for (i = 0; i < IEEE80211_NUM_BANDS; i++)
+		if (wiphy->bands[i])
+			rates[i] = (1 << wiphy->bands[i]->n_bitrates) - 1;
+
+
+	ret = ath6kl_wmi_beginscan_cmd(ar->wmi, 0, WMI_LONG_SCAN, false,
+				       false, 0, ATH6KL_FG_SCAN_INTERVAL,
+				       0, NULL, false, rates);
+	if (ret) {
+		ath6kl_err("failed to start scan for a regdomain change: %d\n",
+			   ret);
+		return ret;
+	}
+
+	return 0;
+}
+
 static int ath6kl_cfg80211_vif_init(struct ath6kl_vif *vif)
 {
 	vif->aggr_cntxt = aggr_init(vif);
@@ -3590,6 +3633,10 @@
 					  BIT(NL80211_IFTYPE_P2P_CLIENT);
 	}
 
+	if (config_enabled(CONFIG_ATH6KL_REGDOMAIN) &&
+	    test_bit(ATH6KL_FW_CAPABILITY_REGDOMAIN, ar->fw_capabilities))
+		wiphy->reg_notifier = ath6kl_cfg80211_reg_notify;
+
 	/* max num of ssids that can be probed during scanning */
 	wiphy->max_scan_ssids = MAX_PROBED_SSIDS;