Speed up synchronization on a port that hassn't been tweaked recently.

Get the speed we try first from looking at the device's current speed,
rather than the last speed stored for it by gpsd.  This means gpsd
will never have to try more than one speed when the device and GPSD
speeds are matched, even if hotplug vicissitudes have renamed a device.

1 files changed, 8 insertions, 13 deletions

diff --git a/serial.c b/serial.c
index dda0b2a0..1e23095f 100644
--- a/serial.c
+++ b/serial.c
@@ -29,7 +29,8 @@ int gpsd_get_speed(struct termios* ttyctl)
     case B9600:  return(9600);
     case B19200: return(19200);
     case B38400: return(38400);
-    default: return(57600);
+    case B57600: return(57600);
+    default: return(115200);
     }
 }
 
@@ -39,7 +40,7 @@ int gpsd_set_speed(struct gps_device_t *session,
     unsigned int	rate;
 
     if (speed < 300)
-	rate = 0;
+	rate = B0;
     else if (speed < 1200)
       rate =  B300;
     else if (speed < 2400)
@@ -60,7 +61,7 @@ int gpsd_set_speed(struct gps_device_t *session,
       rate =  B115200;
 
     tcflush(session->gpsdata.gps_fd, TCIOFLUSH);	/* toss stale data */
-    if (speed!=cfgetispeed(&session->ttyset) || stopbits!=session->gpsdata.stopbits) {
+    if (rate!=cfgetispeed(&session->ttyset) || stopbits!=session->gpsdata.stopbits) {
 	cfsetispeed(&session->ttyset, (speed_t)rate);
 	cfsetospeed(&session->ttyset, (speed_t)rate);
 	session->ttyset.c_cflag &=~ CSIZE;
@@ -84,7 +85,7 @@ int gpsd_open(struct gps_device_t *session)
     unsigned int *ip;
     unsigned int stopbits;
     /* every rate we're likely to see on a GPS */
-    static unsigned int rates[] = {4800, 9600, 19200, 38400, 57600};
+    static unsigned int rates[] = {0, 4800, 9600, 19200, 38400, 57600};
 
     gpsd_report(1, "opening GPS data source at '%s'\n", session->gpsdata.gps_device);
     if ((session->gpsdata.gps_fd = open(session->gpsdata.gps_device, O_RDWR|O_NOCTTY)) < 0) {
@@ -122,17 +123,11 @@ int gpsd_open(struct gps_device_t *session)
 	session->ttyset.c_iflag = session->ttyset.c_oflag = session->ttyset.c_lflag = (tcflag_t) 0;
 	session->ttyset.c_oflag = (ONLCR);
 
-	if (session->gpsdata.baudrate) {
-	    gpsd_report(1, "setting speed %d, %d stopbits, no parity\n", 
-			session->gpsdata.baudrate, 
-			session->gpsdata.stopbits);
-	    if (gpsd_set_speed(session, session->gpsdata.baudrate, session->gpsdata.stopbits)) {
-		return session->gpsdata.gps_fd;
-	    }
-	}
+	rates[0] = gpsd_get_speed(&session->ttyset_old);
 	for (stopbits = 1; stopbits <= 2; stopbits++)
 	    for (ip = rates; ip < rates + sizeof(rates)/sizeof(rates[0]); ip++)
-		if (*ip != session->gpsdata.baudrate || stopbits != session->gpsdata.stopbits) {
+		if (ip == rates || *ip != rates[0])
+		{
 		    gpsd_report(1, 
 				"hunting at speed %d, %dN%d\n",
 				*ip, 9-stopbits, stopbits);