qcacld-3.0: implement new 11d algorithm

Per new US regulations, 11d should be used to chose new country
only if at-least 3 APs with new country are seen; plus no AP with
US country is seen. Apply the same logic for WORLD mode also.

Change-Id: I159e07c8ab6e136c31af33ce1d125fc18063bf5f
CRs-Fixed: 2089601

1 files changed, 88 insertions, 1 deletions

diff --git a/core/sme/src/csr/csr_api_scan.c b/core/sme/src/csr/csr_api_scan.c
index 2164fcf6e1a4..72f244c1e370 100644
--- a/core/sme/src/csr/csr_api_scan.c
+++ b/core/sme/src/csr/csr_api_scan.c
@@ -86,6 +86,8 @@
 #define CSR_SCAN_IS_OVER_BSS_LIMIT(pMac)  \
 	((pMac)->scan.nBssLimit <= (csr_ll_count(&(pMac)->scan.scanResultList)))
 
+#define MIN_11D_AP_COUNT 3
+
 static void csr_set_default_scan_timing(tpAniSirGlobal pMac,
 					tSirScanType scanType,
 					tCsrScanRequest *pScanRequest);
@@ -3146,12 +3148,90 @@ csr_remove_from_tmp_list(tpAniSirGlobal mac_ctx,
 	} /* end of loop */
 }
 
+
+static bool is_us_country(uint8_t *country_code)
+{
+	if ((country_code[0] == 'U') &&
+	    (country_code[1] == 'S'))
+		return true;
+
+	return false;
+}
+
+static bool is_world_mode(uint8_t *country_code)
+{
+	if ((country_code[0] == '0') &&
+	    (country_code[1] == '0'))
+		return true;
+
+	return false;
+}
+
+static bool csr_elected_country_algo_fcc(tpAniSirGlobal mac_ctx)
+{
+	bool ctry_11d_found = false;
+	uint8_t max_votes = 0;
+	uint8_t i = 0;
+	uint8_t ctry_index;
+
+	if (!mac_ctx->scan.countryCodeCount) {
+		sme_warn("No AP with 11d Country code is present in scan list");
+		return ctry_11d_found;
+	}
+
+	max_votes = mac_ctx->scan.votes11d[0].votes;
+	if (is_us_country(mac_ctx->scan.votes11d[0].countryCode)) {
+		ctry_11d_found = true;
+		ctry_index = 0;
+		goto algo_done;
+	} else if (max_votes >= MIN_11D_AP_COUNT) {
+		ctry_11d_found = true;
+		ctry_index = 0;
+	}
+
+	for (i = 1; i < mac_ctx->scan.countryCodeCount; i++) {
+		if (is_us_country(mac_ctx->scan.votes11d[i].countryCode)) {
+			ctry_11d_found = true;
+			ctry_index = i;
+			goto algo_done;
+		}
+
+		if ((max_votes < mac_ctx->scan.votes11d[i].votes) &&
+		    (mac_ctx->scan.votes11d[i].votes >= MIN_11D_AP_COUNT)) {
+			sme_debug(" Votes for Country %c%c : %d",
+				  mac_ctx->scan.votes11d[i].countryCode[0],
+				  mac_ctx->scan.votes11d[i].countryCode[1],
+				  mac_ctx->scan.votes11d[i].votes);
+			max_votes = mac_ctx->scan.votes11d[i].votes;
+			ctry_index = i;
+			ctry_11d_found = true;
+		}
+	}
+
+algo_done:
+
+	if (ctry_11d_found) {
+		qdf_mem_copy(mac_ctx->scan.countryCodeElected,
+			     mac_ctx->scan.votes11d[ctry_index].countryCode,
+			     WNI_CFG_COUNTRY_CODE_LEN);
+
+		sme_debug("Selected Country is %c%c With count %d",
+			  mac_ctx->scan.votes11d[ctry_index].countryCode[0],
+			  mac_ctx->scan.votes11d[ctry_index].countryCode[1],
+			  mac_ctx->scan.votes11d[ctry_index].votes);
+	}
+
+	return ctry_11d_found;
+}
+
+
 static void csr_move_temp_scan_results_to_main_list(tpAniSirGlobal pMac,
 						    uint8_t reason,
 						    uint8_t sessionId)
 {
 	tCsrRoamSession *pSession;
 	uint32_t i;
+	bool found_11d_ctry = false;
 
 	/* remove the BSS descriptions from temporary list */
 	csr_remove_from_tmp_list(pMac, reason, sessionId);
@@ -3171,7 +3251,14 @@ static void csr_move_temp_scan_results_to_main_list(tpAniSirGlobal pMac,
 			return;
 		}
 	}
-	if (csr_elected_country_info(pMac))
+
+	if (is_us_country(pMac->scan.countryCodeCurrent) ||
+	    is_world_mode(pMac->scan.countryCodeCurrent))
+		found_11d_ctry = csr_elected_country_algo_fcc(pMac);
+	else
+		found_11d_ctry = csr_elected_country_info(pMac);
+
+	if (found_11d_ctry)
 		csr_learn_11dcountry_information(pMac, NULL, NULL, true);
 }