Use echo training of FXS (fxo signalled) interfaces... rest to follow

git-svn-id: https://origsvn.digium.com/svn/asterisk/trunk@1677 65c4cc65-6c06-0410-ace0-fbb531ad65f3

diff --git a/channels/chan_zap.c b/channels/chan_zap.c
index 77f1fc0..875c48f 100755 (executable)
--- a/channels/chan_zap.c
+++ b/channels/chan_zap.c
@@ -172,6 +172,8 @@ static float txgain = 0.0;
 
 static int echocancel;
 
+static int echotraining;
+
 static int echocanbridged = 0;
 
 static int busydetect = 0;
@@ -403,6 +405,7 @@ static struct zt_pvt {
        int callwaitcas;
        int callwaitrings;
        int echocancel;
+       int echotraining;
        int echocanbridged;
        int echocanon;
        int permcallwaiting;
@@ -1064,6 +1067,22 @@ static void zt_enable_ec(struct zt_pvt *p)
                ast_log(LOG_DEBUG, "No echocancellation requested\n");
 }
 
+static void zt_train_ec(struct zt_pvt *p)
+{
+       int x;
+       int res;
+       if (p && p->echocancel && p->echotraining) {
+               x = 400;
+               res = ioctl(p->subs[SUB_REAL].zfd, ZT_ECHOTRAIN, &x);
+               if (res) 
+                       ast_log(LOG_WARNING, "Unable to request echo training on channel %d\n", p->channel);
+               else {
+                       ast_log(LOG_DEBUG, "Engaged echo training on channel %d\n", p->channel);
+               }
+       } else
+               ast_log(LOG_DEBUG, "No echo training requested\n");
+}
+
 static void zt_disable_ec(struct zt_pvt *p)
 {
        int x;
@@ -2814,6 +2833,7 @@ static struct ast_frame *zt_handle_event(struct ast_channel *ast)
                                switch(ast->_state) {
                                case AST_STATE_RINGING:
                                        zt_enable_ec(p);
+                                       zt_train_ec(p);
                                        p->subs[index].f.frametype = AST_FRAME_CONTROL;
                                        p->subs[index].f.subclass = AST_CONTROL_ANSWER;
                                        /* Make sure it stops ringing */
@@ -5149,6 +5169,7 @@ static struct zt_pvt *mkintf(int channel, int signalling, int radio)
                tmp->permhidecallerid = hidecallerid;
                tmp->callreturn = callreturn;
                tmp->echocancel = echocancel;
+               tmp->echotraining = echotraining;
                tmp->echocanbridged = echocanbridged;
                tmp->busydetect = busydetect;
                tmp->busycount = busycount;
@@ -6773,6 +6794,8 @@ int load_module()
                                if (echocancel)
                                        echocancel=128;
                        }
+               } else if (!strcasecmp(v->name, "echotraining")) {
+                       echotraining = ast_true(v->value);
                } else if (!strcasecmp(v->name, "hidecallerid")) {
                        hidecallerid = ast_true(v->value);
                } else if (!strcasecmp(v->name, "callreturn")) {

diff --git a/configs/zapata.conf.sample b/configs/zapata.conf.sample
index 8d22e3c..31619af 100755 (executable)
--- a/configs/zapata.conf.sample
+++ b/configs/zapata.conf.sample
@@ -145,6 +145,14 @@ echocancel=yes
 ;
 echocancelwhenbridged=yes
 ;
+; In some cases, the echo canceller doesn't train quickly enough and there
+; is echo at the beginning of the call.  Enabling echo training will cause
+; asterisk to briefly mute the channel, send an impulse, and use the impulse
+; response to pre-train the echo canceller so it can start out with a much
+; closer idea of the actual echo.
+;
+;echotraining=yes
+;
 ; If you are having trouble with DTMF detection, you can relax the
 ; DTMF detection parameters.  Relaxing them may make the DTMF detector
 ; more likely to have "talkoff" where DTMF is detected when it