From 03af723216afffaf57d9bb78d71a80a32adb7d9a Mon Sep 17 00:00:00 2001
From: Jaroslav Kysela <perex@perex.cz>
Date: Thu, 18 Sep 2014 10:35:42 +0200
Subject: [PATCH] linuxdvb: rotor - try to fix the grace calculation routine
 for USALS and negative longtitudes

---
 src/input/mpegts/linuxdvb/linuxdvb_rotor.c | 20 ++++++++++++++++----
 src/tvheadend.h                            |  1 +
 2 files changed, 17 insertions(+), 4 deletions(-)

diff --git a/src/input/mpegts/linuxdvb/linuxdvb_rotor.c b/src/input/mpegts/linuxdvb/linuxdvb_rotor.c
index 68c2dd36..72374024 100644
--- a/src/input/mpegts/linuxdvb/linuxdvb_rotor.c
+++ b/src/input/mpegts/linuxdvb/linuxdvb_rotor.c
@@ -134,16 +134,28 @@ linuxdvb_rotor_grace
   ( linuxdvb_diseqc_t *ld, dvb_mux_t *lm )
 {
   linuxdvb_rotor_t *lr = (linuxdvb_rotor_t*)ld;
+  linuxdvb_satconf_t *ls = ld->ld_satconf->lse_parent;
+  int newpos, curpos, delta;
 
-  if (!ld->ld_satconf->lse_parent->ls_orbital_dir || lr->lr_rate == 0)
+  if (!ls->ls_orbital_dir || lr->lr_rate == 0)
     return 120;
 
-  int curpos = ld->ld_satconf->lse_parent->ls_orbital_pos;
+  if (idnode_is_instance(&lr->ld_id, &linuxdvb_rotor_gotox_class))
+    newpos = lr->lr_position;                /* GotoX */
+  else
+    newpos = (lr->lr_sat_lon + 0.005) * 100; /* USALS */
 
-  if (ld->ld_satconf->lse_parent->ls_orbital_dir == 'W')
+  curpos = ls->ls_orbital_pos;
+  if (ls->ls_orbital_dir == 'W')
     curpos = -(curpos);
+  delta = abs(deltaI32(curpos, newpos));
 
-  return (lr->lr_rate*(deltaU32(curpos, lr->lr_position))+999)/1000;
+  /* ignore very small movements like 0.8W and 1W */
+  if (delta <= 2)
+    return 0;
+
+  /* add one extra second, because of the rounding issue */
+  return ((lr->lr_rate*delta+999)/1000) + 1;
 }
 
 static int
diff --git a/src/tvheadend.h b/src/tvheadend.h
index d32d8c16..87ca0114 100644
--- a/src/tvheadend.h
+++ b/src/tvheadend.h
@@ -708,6 +708,7 @@ int rmtree ( const char *path );
 
 char *regexp_escape ( const char *str );
 
+static inline int32_t deltaI32(int32_t a, int32_t b) { return (a > b) ? (a - b) : (b - a); }
 static inline uint32_t deltaU32(uint32_t a, uint32_t b) { return (a > b) ? (a - b) : (b - a); }
   
 #define SKEL_DECLARE(name, type) type *name;