net: config: sntp: add option for failure try interval

add option for a different resync interval, that is
applied when the sntp request fails.

Signed-off-by: Fin Maaß <f.maass@vogl-electronic.com>

Author: maass-hamburg

subsys/net/lib/config/Kconfig

@@ -244,9 +244,18 @@ config NET_CONFIG_SNTP_INIT_RESYNC
 	  Perform an SNTP request over networking periodically to get and
 	  absolute wall clock time, and resync system time from it.
 
+if NET_CONFIG_SNTP_INIT_RESYNC
+
 config NET_CONFIG_SNTP_INIT_RESYNC_INTERVAL
 	int "SNTP resync interval (sec)"
-	depends on NET_CONFIG_SNTP_INIT_RESYNC
 	default 3600
 
+config NET_CONFIG_SNTP_INIT_RESYNC_ON_FAILURE_INTERVAL
+	int "SNTP resync interval (sec) on failure"
+	default NET_CONFIG_SNTP_INIT_RESYNC_INTERVAL
+	help
+	  If the SNTP request fails, then this is the interval to wait
+	  before trying again.
+
+endif # NET_CONFIG_SNTP_INIT_RESYNC
 endif # NET_CONFIG_CLOCK_SNTP_INIT

subsys/net/lib/config/init_clock_sntp.c

@@ -54,8 +54,10 @@ int net_init_clock_via_sntp(void)
 
 end:
 #ifdef CONFIG_NET_CONFIG_SNTP_INIT_RESYNC
-	k_work_reschedule(&sntp_resync_work_handle,
-			  K_SECONDS(CONFIG_NET_CONFIG_SNTP_INIT_RESYNC_INTERVAL));
+	k_work_reschedule(
+		&sntp_resync_work_handle,
+		(res < 0) ? K_SECONDS(CONFIG_NET_CONFIG_SNTP_INIT_RESYNC_ON_FAILURE_INTERVAL)
+			  : K_SECONDS(CONFIG_NET_CONFIG_SNTP_INIT_RESYNC_INTERVAL));
 #endif
 	return res;
 }