From 9f3a0a3df4346fa15ed6573cc57092baba37354e Mon Sep 17 00:00:00 2001
From: Cole Walker <cole.walker@windriver.com>
Date: Wed, 23 Jun 2021 11:14:41 -0400
Subject: [PATCH 6/6] Add option to disable default port selection in phc2sys

---
 config.c  |  1 +
 phc2sys.c | 19 ++++++++++++++-----
 2 files changed, 15 insertions(+), 5 deletions(-)

diff --git a/config.c b/config.c
index 7914ba4..de5e68e 100644
--- a/config.c
+++ b/config.c
@@ -273,6 +273,7 @@ struct config_item config_tab[] = {
 	GLOB_ITEM_STR("userDescription", ""),
 	GLOB_ITEM_INT("utc_offset", CURRENT_UTC_OFFSET, 0, INT_MAX),
 	GLOB_ITEM_INT("verbose", 0, 0, 1),
+	GLOB_ITEM_INT("default_sync", 1, 0, 1),
 };

 static struct unicast_master_table *current_uc_mtab;
diff --git a/phc2sys.c b/phc2sys.c
index b8f1ea0..45dba55 100644
--- a/phc2sys.c
+++ b/phc2sys.c
@@ -120,6 +120,7 @@ struct node {
 	LIST_HEAD(clock_head, clock) clocks;
 	LIST_HEAD(dst_clock_head, clock) dst_clocks;
 	struct clock *master;
+	int default_sync;
 };

 static struct config *phc2sys_config;
@@ -465,7 +466,7 @@ static void reconfigure(struct node *node)
 		}
 		last = c;
 	}
-	if (dst_cnt > 1 && !src) {
+	if (dst_cnt > 1 && !src && node->default_sync) {
 		if (!rt || rt->dest_only) {
 			node->master = last;
 			/* Reset to original state in next reconfiguration. */
@@ -1363,6 +1364,7 @@ static void usage(char *progname)
 		" -N [num]       number of master clock readings per update (5)\n"
 		" -L [limit]     sanity frequency limit in ppb (200000000)\n"
 		" -M [num]       NTP SHM segment number (0)\n"
+		" -D [num]       fall back to default clock in automatic mode (1)\n"
 		" -u [num]       number of clock updates in summary stats (0)\n"
 		" -n [num]       domain number (0)\n"
 		" -x             apply leap seconds by servo instead of kernel\n"
@@ -1383,7 +1385,7 @@ int main(int argc, char *argv[])
 	struct clock *src, *dst;
 	struct config *cfg;
 	struct option *opts;
-	int autocfg = 0, c, domain_number = 0, index, ntpshm_segment;
+	int autocfg = 0, c, domain_number = 0, default_sync = 1, index, ntpshm_segment;
 	int pps_fd = -1, print_level = LOG_INFO, r = -1, rt = 0, wait_sync = 0;
 	double phc_rate, tmp;
 	struct node node = {
@@ -1407,7 +1409,7 @@ int main(int argc, char *argv[])
 	progname = strrchr(argv[0], '/');
 	progname = progname ? 1+progname : argv[0];
 	while (EOF != (c = getopt_long(argc, argv,
-				"arc:d:f:s:E:P:I:S:F:R:N:O:L:M:i:u:wn:xz:l:t:mqvh",
+				"arc:d:f:s:E:P:I:S:F:R:N:O:L:M:D:i:u:wn:xz:l:t:mqvh",
 				opts, &index))) {
 		switch (c) {
 		case 0:
@@ -1559,6 +1561,12 @@ int main(int argc, char *argv[])
 			version_show(stdout);
 			config_destroy(cfg);
 			return 0;
+		case 'D':
+			if (get_arg_val_i(c, optarg, &default_sync, 0, 1) ||
+			config_set_int(cfg, "default_sync", default_sync)) {
+				goto end;
+			}
+			break;
 		case 'h':
 			usage(progname);
 			config_destroy(cfg);
@@ -1607,8 +1615,9 @@ int main(int argc, char *argv[])
 	}
 	node.kernel_leap = config_get_int(cfg, NULL, "kernel_leap");
 	node.sanity_freq_limit = config_get_int(cfg, NULL, "sanity_freq_limit");
-
-	if (autocfg) {
+	node.default_sync = config_get_int(cfg, NULL, "default_sync");
+
+	if (autocfg) {
 		if (init_pmc(cfg, &node))
 			goto end;
 		if (auto_init_ports(&node, rt) < 0)
--
2.29.2