[FEATURE: #335] userspace/tools/nmea: NMEA contains time in UTC not as GPS

Signed-off-by: Adam Wujek <dev_public@wujek.eu>

userspace/tools/nmea/nmea.c

@@ -356,7 +356,7 @@ int nmea_parse_gpzda(const char *buff, int buff_sz, nmea_time_t *utc)
     return 1;
 }
 
-int64_t nmea_time_to_tai(nmea_time_t t)
+int64_t utc_time_to_utc_seconds(nmea_time_t t)
 {
 	short month, year;
 	int64_t result;
@@ -387,5 +387,5 @@ int64_t nmea_time_to_tai(nmea_time_t t)
 	result *= 60;
 	result += t.sec;
 
-	return(result + 19LL); /* TAI = GPS + 19 s */
+	return(result);
 }

userspace/tools/nmea/nmea.h

@@ -60,6 +60,6 @@ typedef struct
 
 int nmea_parse_gprmc(const char *buff, int buff_sz, nmea_time_t *utc);
 int nmea_parse_gpzda(const char *buff, int buff_sz, nmea_time_t *utc);
-int64_t nmea_time_to_tai(nmea_time_t t);
+int64_t utc_time_to_utc_seconds(nmea_time_t t);
 
 #endif /* __NMEA_H__ */

userspace/tools/nmea/wr_nmea.c

@@ -99,7 +99,7 @@ int read_nmea_msg_type(char *msgbuf, int len, const char *msg_type)
 	return 0;
 }
 
-int nmea_read_tai(struct wr_nmea *nmea, int64_t *t_out)
+int nmea_read_utc(struct wr_nmea *nmea, int64_t *t_out)
 {
     char buf[1024];
 
@@ -108,6 +108,7 @@ int nmea_read_tai(struct wr_nmea *nmea, int64_t *t_out)
 	return -1;
     serial_close();
 
+    /* NMEA time is provided as UTC */
     if(nmea->parse(buf, strlen(buf), (nmea->utc)) < 0)
 	return -2;
 
@@ -120,7 +121,7 @@ int nmea_read_tai(struct wr_nmea *nmea, int64_t *t_out)
 	    nmea->utc->sec,
 	    nmea->utc->hsec);
 
-    *t_out = nmea_time_to_tai(*(nmea->utc));
+    *t_out = utc_time_to_utc_seconds(*(nmea->utc));
 
     return 0;
 }

userspace/tools/nmea/wr_nmea.h

@@ -13,5 +13,5 @@ struct wr_nmea {
 };
 
 int nmea_init(struct wr_nmea *nmea, char *dev, int baud, char *fmt);
-int nmea_read_tai(struct wr_nmea *nmea, int64_t *t_out);
+int nmea_read_utc(struct wr_nmea *nmea, int64_t *t_out);
 #endif

userspace/tools/wr_date.c

@@ -136,11 +136,11 @@ int get_kern_leaps(void)
 	//return t.tai;
 }
 
-static int wrdate_get_nmea(int64_t *t_out)
+static int wrdate_get_nmea_utc(int64_t *t_out)
 {
 	int ret;
 	
-	ret = nmea_read_tai(&nmea, t_out);
+	ret = nmea_read_utc(&nmea, t_out);
 
 	if (ret == -1) {
 		fprintf(stderr, "Timeout on reading nmea\n");
@@ -158,7 +158,7 @@ static int wrdate_get_nmea(int64_t *t_out)
 static int wrdate_gettimeofday(struct timeval *tv)
 {
 	if (opt_nmea_en) {
-		return wrdate_get_nmea((int64_t *)&tv->tv_sec);
+		return wrdate_get_nmea_utc((int64_t *)&tv->tv_sec);
 	} else {
 		return gettimeofday(tv, NULL);
 	}