qcacld-3.0: Follow concurrent SAP switch channel in the same band

When lte channel avoidance event triggered, multiple SAP will choose
safe channel from pcl/acs combination and switch to the safe channel
one by one.

Actually when force SCC mode is enabled, if one SAP is the same band
as other concurrent SAP whose channel is already safe, it doesn't
need to choose safe channel from pcl/acs again, just needs to
follow concurrent SAP channel. Add code to implement this policy.

Change-Id: Icc9b2a53bb56915daeab8d94eceaaa64a660cb65
CRs-Fixed: 2500183

core/hdd/src/wlan_hdd_main.c

@@ -9069,6 +9069,32 @@ int hdd_update_acs_timer_reason(struct hdd_adapter *adapter, uint8_t reason)
 }
 
 #if defined(FEATURE_WLAN_CH_AVOID)
+/**
+ * hdd_store_sap_restart_channel() - store sap restart channel
+ * @restart_chan: restart channel
+ * @restart_chan_store: pointer to restart channel store
+ *
+ * The function will store new sap restart channel.
+ *
+ * Return - none
+ */
+static void
+hdd_store_sap_restart_channel(uint8_t restart_chan, uint8_t *restart_chan_store)
+{
+	uint8_t i;
+
+	for (i = 0; i < SAP_MAX_NUM_SESSION; i++) {
+		if (*(restart_chan_store + i) == restart_chan)
+			return;
+
+		if (*(restart_chan_store + i))
+			continue;
+
+		*(restart_chan_store + i) = restart_chan;
+		return;
+	}
+}
+
 /**
  * hdd_unsafe_channel_restart_sap() - restart sap if sap is on unsafe channel
  * @hdd_ctx: hdd context pointer
@@ -9084,6 +9110,7 @@ void hdd_unsafe_channel_restart_sap(struct hdd_context *hdd_ctxt)
 	struct hdd_adapter *adapter;
 	uint32_t i;
 	bool found = false;
+	uint8_t restart_chan_store[SAP_MAX_NUM_SESSION] = {0};
 	uint8_t restart_chan;
 	uint8_t scc_on_lte_coex = 0;
 	bool value;
@@ -9132,6 +9159,9 @@ void hdd_unsafe_channel_restart_sap(struct hdd_context *hdd_ctxt)
 			}
 		}
 		if (!found) {
+			hdd_store_sap_restart_channel(
+				adapter->session.ap.operating_channel,
+				restart_chan_store);
 			hdd_debug("ch:%d is safe. no need to change channel",
 				  adapter->session.ap.operating_channel);
 			continue;
@@ -9153,10 +9183,27 @@ void hdd_unsafe_channel_restart_sap(struct hdd_context *hdd_ctxt)
 			hdd_update_acs_timer_reason(adapter,
 				QCA_WLAN_VENDOR_ACS_SELECT_REASON_LTE_COEX);
 			continue;
-		} else
+		}
+
+		restart_chan = 0;
+		for (i = 0; i < SAP_MAX_NUM_SESSION; i++) {
+			if (!restart_chan_store[i])
+				continue;
+
+			if (policy_mgr_is_force_scc(hdd_ctxt->psoc) &&
+			    WLAN_REG_IS_SAME_BAND_CHANNELS(
+							restart_chan_store[i],
+							adapter->session.ap.
+							operating_channel)) {
+				restart_chan = restart_chan_store[i];
+				break;
+			}
+		}
+		if (!restart_chan)
 			restart_chan =
 				wlansap_get_safe_channel_from_pcl_and_acs_range(
 					WLAN_HDD_GET_SAP_CTX_PTR(adapter));
+
 		if (!restart_chan) {
 			hdd_err("fail to restart SAP");
 		} else {
@@ -9176,6 +9223,9 @@ void hdd_unsafe_channel_restart_sap(struct hdd_context *hdd_ctxt)
 						CSA_REASON_UNSAFE_CHANNEL);
 				hdd_switch_sap_channel(adapter, restart_chan,
 						       true);
+				hdd_store_sap_restart_channel(
+							restart_chan,
+							restart_chan_store);
 			}
 			else {
 				hdd_debug("sending coex indication");