[layer23] Completed GPS reading process

This includes "double" values of logitude and latitude, as well as time
stamp, and if the values are valid or not (GPS fix).

diff --git a/src/host/layer23/include/osmocom/bb/common/logging.h b/src/host/layer23/include/osmocom/bb/common/logging.h
index 683c685..eb9f482 100644 (file)
--- a/src/host/layer23/include/osmocom/bb/common/logging.h
+++ b/src/host/layer23/include/osmocom/bb/common/logging.h
@@ -20,6 +20,7 @@ enum {
        DSAP,
        DSUM,
        DSIM,
+       DGPS,
 };
 
 extern const struct log_info log_info;

diff --git a/src/host/layer23/include/osmocom/bb/mobile/gps.h b/src/host/layer23/include/osmocom/bb/mobile/gps.h
index a62eab7..b3b4335 100644 (file)
--- a/src/host/layer23/include/osmocom/bb/mobile/gps.h
+++ b/src/host/layer23/include/osmocom/bb/mobile/gps.h
@@ -20,9 +20,15 @@
  */
 
 struct gps {
-       uint8_t enable;
-       char device[32];
-       uint32_t baud;
+       /* GPS device */
+       uint8_t         enable;
+       char            device[32];
+       uint32_t        baud;
+
+       /* current data */
+       uint8_t         valid; /* we have a fix */
+       time_t          gmt; /* GMT time when position was received */
+       double          latitude, longitude;
 };
 
 extern struct gps gps;

diff --git a/src/host/layer23/src/mobile/gps.c b/src/host/layer23/src/mobile/gps.c
index 520aff8..c66da6d 100644 (file)
--- a/src/host/layer23/src/mobile/gps.c
+++ b/src/host/layer23/src/mobile/gps.c
@@ -25,16 +25,22 @@
 #include <unistd.h>
 #include <stdlib.h>
 #include <errno.h>
+#include <time.h>
 
 #include <osmocore/utils.h>
 
 #include <osmocom/bb/common/osmocom_data.h>
+#include <osmocom/bb/common/logging.h>
 #include <osmocom/bb/mobile/gps.h>
 
 struct gps gps = {
        0,
        "/dev/ttyACM0",
-       0
+       0,
+
+       0,
+       0,
+       0,0,
 };
 
 static struct bsc_fd gps_bfd;
@@ -42,6 +48,11 @@ static struct termios gps_termios, gps_old_termios;
 
 static int gps_line(char *line)
 {
+       time_t gps_now, host_now;
+       struct tm *tm;
+       int32_t diff;
+       double latitude, longitude;
+
        if (!!strncmp(line, "$GPGLL", 6))
                return 0;
        line += 7;
@@ -50,8 +61,66 @@ static int gps_line(char *line)
        line[37] = '\0';
        /* ddmm.mmmm,N,dddmm.mmmm,E,hhmmss.mmm,A */
 
-       printf("'%s'\n", line);
-
+       /* valid position */
+       if (line[36] != 'A') {
+               LOGP(DGPS, LOGL_INFO, "%s (invalid)\n", line);
+               gps.valid = 0;
+       }
+       gps.valid = 1;
+
+       /* time stamp */
+       gps_now = line[30] - '0';
+       gps_now += (line[29] - '0') * 10;
+       gps_now += (line[28] - '0') * 60;
+       gps_now += (line[27] - '0') * 600;
+       gps_now += (line[26] - '0') * 3600;
+       gps_now += (line[25] - '0') * 36000;
+       time(&host_now);
+       /* calculate the number of seconds the host differs from GPS */
+       diff = host_now % 86400 - gps_now;
+       if (diff < 0)
+               diff += 86400;
+       if (diff >= 43200)
+               diff -= 86400;
+       /* apply the "date" part to the GPS time */
+       gps_now = host_now - diff;
+       gps.gmt = gps_now;
+       tm = localtime(&gps_now);
+
+       /* position */
+       latitude = (double)(line[0] - '0') * 10.0;
+       latitude += (double)(line[1] - '0');
+       latitude += (double)(line[2] - '0') / 6.0;
+       latitude += (double)(line[3] - '0') / 60.0;
+       latitude += (double)(line[5] - '0') / 600.0;
+       latitude += (double)(line[6] - '0') / 6000.0;
+       latitude += (double)(line[7] - '0') / 60000.0;
+       latitude += (double)(line[8] - '0') / 600000.0;
+       if (line[10] == 'S')
+               latitude = 0.0 - latitude;
+       gps.latitude = latitude;
+       longitude = (double)(line[12] - '0') * 100.0;
+       longitude += (double)(line[13] - '0') * 10.0;
+       longitude += (double)(line[14] - '0');
+       longitude += (double)(line[15] - '0') / 6.0;
+       longitude += (double)(line[16] - '0') / 60.0;
+       longitude += (double)(line[18] - '0') / 600.0;
+       longitude += (double)(line[19] - '0') / 6000.0;
+       longitude += (double)(line[20] - '0') / 60000.0;
+       longitude += (double)(line[21] - '0') / 600000.0;
+       if (line[23] == 'W')
+               longitude = 360.0 - longitude;
+       gps.longitude = longitude;
+       
+       LOGP(DGPS, LOGL_INFO, "%s\n", line);
+       LOGP(DGPS, LOGL_INFO, " time=%02d:%02d:%02d %04d-%02d-%02d, "
+               "diff-to-host=%d, latitude=%do%.4f, longitude=%do%.4f\n",
+               tm->tm_hour, tm->tm_min, tm->tm_sec, tm->tm_year + 1900,
+               tm->tm_mday, tm->tm_mon + 1, diff,
+               (int)gps.latitude,
+               (gps.latitude - ((int)gps.latitude)) * 60.0,
+               (int)gps.longitude,
+               (gps.longitude - ((int)gps.longitude)) * 60.0);
        return 0;
 }
 
@@ -112,6 +181,9 @@ int gps_open(void)
 
        if (gps_bfd.fd > 0)
                return 0;
+
+       LOGP(DGPS, LOGL_INFO, "Open GPS device '%s'\n", gps.device);
+
        gps_bfd.data = NULL;
        gps_bfd.when = BSC_FD_READ;
        gps_bfd.cb = gps_cb;
@@ -159,6 +231,8 @@ void gps_close(void)
        if (gps_bfd.fd <= 0)
                return;
 
+       LOGP(DGPS, LOGL_INFO, "Close GPS device\n");
+
        bsc_unregister_fd(&gps_bfd);
 
        if (isatty(gps_bfd.fd))