Fix Kenwood TS-870s split and bandwidth set/get.

The TS-870s has no width set for SSB and AM, instead the bandwidth is
set via a high and low pass fiter setting. The backend now sets these
to try and achieve the requested bandwidth. The HPF setting is assumed
to be the default.

The bandwidth query reads both the HPF and the LPF and returns the
difference.

The value of RIG_BANDWIDTH_NORMAL skips bandwidth adjustements.

The get and set_split operations have been enabled.

kenwood/ts870s.c

@@ -140,6 +140,24 @@ static int ts870s_get_mode(RIG *rig, vfo_t vfo, rmode_t *mode, pbwidth_t *width)
 
   *width = 10 * atoi(&buf[2]);
 
+  if (RIG_MODE_USB == *mode || RIG_MODE_LSB == *mode || RIG_MODE_AM == *mode)
+    {
+      /* we only have HPF value and need LPF as well to calculate bandwidth */
+
+      retval = kenwood_transaction (rig, "IS", 2, buf, &buf_len);
+      if (retval != RIG_OK)
+	return retval;
+
+      if (buf_len != 8 || buf[1] != 'S')
+	{
+	  rig_debug(RIG_DEBUG_ERR,"%s: unexpected IS answer, len=%d\n",
+		    __func__,buf_len);
+	  return -RIG_ERJCTED;
+	}
+
+      *width = atoi (&buf[3]) - *width; /* bandwidth <- LPF - HPF */
+    }
+
   return RIG_OK;
 }
 
@@ -147,6 +165,7 @@ static int ts870s_set_mode(RIG *rig, vfo_t vfo, rmode_t mode, pbwidth_t width)
 {
   char buf[16];
   int kmode, retval;
+  pbwidth_t mode_default_hpf;
 
   switch (mode)
   {
@@ -168,12 +187,35 @@ static int ts870s_set_mode(RIG *rig, vfo_t vfo, rmode_t mode, pbwidth_t width)
   retval = kenwood_simple_cmd(rig, buf);
   if (retval != RIG_OK) return retval;
 
-/*
- * This rig will simply use an IF bandpass which is closest to width,
- * so we don't need to check the value...
- */
-  sprintf(buf, "FW%04d", (int)width/10);
-  return kenwood_simple_cmd(rig, buf);
+  if (RIG_PASSBAND_NORMAL != width) /* leave well alone if default passband requested */
+    {
+      if (RIG_MODE_USB == mode || RIG_MODE_LSB == mode || RIG_MODE_AM == mode)
+	{
+	  /* we assume the HPF is set to default and set the LPF to
+	     give the best approximaation of the requested width */
+	  if (RIG_MODE_AM == mode)
+	    {
+	      mode_default_hpf = 300;
+	    }
+	  else
+	    {
+	      mode_default_hpf = 100;
+	    }
+	  sprintf(buf, "IS %04d", (int)(width + mode_default_hpf));
+	  retval = kenwood_simple_cmd(rig, buf);
+	}
+      else
+	{
+	  /*
+	   * This rig will simply use an IF bandpass which is closest to width,
+	   * so we don't need to check the value...
+	   */
+	  sprintf(buf, "FW%04d", (int)width/10);
+	  retval = kenwood_simple_cmd(rig, buf);
+	}
+    }
+
+  return retval;
 }
 
 int ts870s_set_level(RIG *rig, vfo_t vfo, setting_t level, value_t val)
@@ -500,6 +542,8 @@ const struct rig_caps ts870s_caps = {
 .get_mode =  ts870s_get_mode,
 .set_vfo =  kenwood_set_vfo,
 .get_vfo =  ts870s_get_vfo,
+.set_split_vfo = kenwood_set_split_vfo,
+.get_split_vfo = kenwood_get_split_vfo_if,
 .set_ctcss_tone =  kenwood_set_ctcss_tone,
 .get_ctcss_tone =  kenwood_get_ctcss_tone,
 .get_ptt =  kenwood_get_ptt,