From 28ef713160bdf73fc003f85899a26c3331ce5a1a Mon Sep 17 00:00:00 2001
From: Xavier Arteaga <xavier@softwareradiosystems.com>
Date: Wed, 2 May 2018 18:33:53 +0200
Subject: [PATCH] AGC does not get stuck in high gain if low signal. AGC is now
 default.

---
 lib/src/phy/rf/rf_imp.c | 19 ++++++++++---------
 srsue/ue.conf.example   |  2 +-
 2 files changed, 11 insertions(+), 10 deletions(-)

diff --git a/lib/src/phy/rf/rf_imp.c b/lib/src/phy/rf/rf_imp.c
index 1de66e066..c3d8d9516 100644
--- a/lib/src/phy/rf/rf_imp.c
+++ b/lib/src/phy/rf/rf_imp.c
@@ -41,13 +41,13 @@ int rf_get_available_devices(char **devnames, int max_strlen) {
 
 double srslte_rf_set_rx_gain_th(srslte_rf_t *rf, double gain)
 {
-  if (gain > rf->new_rx_gain + 2 || gain < rf->new_rx_gain - 2) {
+  if (gain > rf->cur_rx_gain + 2 || gain < rf->cur_rx_gain - 2){
     pthread_mutex_lock(&rf->mutex);
     rf->new_rx_gain = gain; 
     pthread_cond_signal(&rf->cond);
     pthread_mutex_unlock(&rf->mutex);
   }
-  return gain; 
+  return rf->cur_rx_gain;
 }
 
 void srslte_rf_set_tx_rx_gain_offset(srslte_rf_t *rf, double offset) {
@@ -65,8 +65,9 @@ static void* thread_gain_fcn(void *h) {
       pthread_cond_wait(&rf->cond, &rf->mutex);
     }
     if (rf->new_rx_gain != rf->cur_rx_gain) {
-      rf->cur_rx_gain = rf->new_rx_gain; 
-      srslte_rf_set_rx_gain(h, rf->cur_rx_gain);
+      srslte_rf_set_rx_gain(h, rf->new_rx_gain);
+      rf->cur_rx_gain = srslte_rf_get_rx_gain(h);
+      rf->new_rx_gain = rf->cur_rx_gain;
     }
     if (rf->tx_gain_same_rx) {
       printf("setting also tx\n");
@@ -80,17 +81,17 @@ static void* thread_gain_fcn(void *h) {
 
 /* Create auxiliary thread and mutexes for AGC */
 int srslte_rf_start_gain_thread(srslte_rf_t *rf, bool tx_gain_same_rx) {
-  rf->tx_gain_same_rx = tx_gain_same_rx; 
-  rf->tx_rx_gain_offset = 0.0; 
+  rf->tx_gain_same_rx = tx_gain_same_rx;
+  rf->tx_rx_gain_offset = 0.0;
   if (pthread_mutex_init(&rf->mutex, NULL)) {
-    return -1; 
+    return -1;
   }
   if (pthread_cond_init(&rf->cond, NULL)) {
-    return -1; 
+    return -1;
   }
   if (pthread_create(&rf->thread_gain, NULL, thread_gain_fcn, rf)) {
     perror("pthread_create");
-    return -1; 
+    return -1;
   }
   return 0;
 }
diff --git a/srsue/ue.conf.example b/srsue/ue.conf.example
index 7224cf8e3..9e244bad6 100644
--- a/srsue/ue.conf.example
+++ b/srsue/ue.conf.example
@@ -28,7 +28,7 @@
 dl_earfcn = 3400
 freq_offset = 0
 tx_gain = 80
-rx_gain = 40
+#rx_gain = 40
 
 #nof_rx_ant = 1
 #device_name = auto