Allow number of VPM spans with hardware echo can to be adjusted

git-svn-id: http://svn.digium.com/svn/zaptel/trunk@765 5390a7c7-147a-4af0-8ec9-7488f05a26cb

1 files changed, 93 insertions, 11 deletions

diff --git a/wct4xxp.c b/wct4xxp.c
index 92bb889..a5cf785 100755
--- a/wct4xxp.c
+++ b/wct4xxp.c
@@ -174,6 +174,7 @@ static int loopback = 0;
 static int alarmdebounce = 0;
 #ifdef VPM_SUPPORT
 static int vpmsupport = 1;
+static int vpmspans = 4;
 #define VPM_DEFAULT_DTMFTHRESHOLD 1000
 static int dtmfthreshold = VPM_DEFAULT_DTMFTHRESHOLD;
 static int lastdtmfthreshold = VPM_DEFAULT_DTMFTHRESHOLD;
@@ -691,6 +692,25 @@ static int t4_dacs(struct zt_chan *dst, struct zt_chan *src)
 }
 
 #ifdef VPM_SUPPORT
+
+static int t4_vpm_unit(int span, int channel)
+{
+	int unit = 0;
+	switch(vpmspans) {
+	case 4:
+		unit = span;
+		unit += (channel & 1) << 2;
+		break;
+	case 2:
+		unit = span;
+		unit += (channel & 0x3) << 1;
+	case 1:
+		unit = span;
+		unit += (channel & 0x7);
+	}
+	return unit;
+}
+
 static int t4_echocan(struct zt_chan *chan, int eclen)
 {
 	struct t4 *wc = chan->pvt;
@@ -698,13 +718,15 @@ static int t4_echocan(struct zt_chan *chan, int eclen)
 	int unit;
 	if (!wc->vpm)
 		return -ENODEV;
-	unit = chan->span->offset;
+
+	if (chan->span->offset >= vpmspans)
+		return -ENODEV;
+
 	if (wc->t1e1)
 		channel = chan->chanpos;
 	else
 		channel = chan->chanpos + 4;
-	if ((channel & 1))
-		unit += 4;
+	unit = t4_vpm_unit(chan->span->offset, channel);
 	if(debug & DEBUG_ECHOCAN) 
 		printk("echocan: Card is %d, Channel is %d, Span is %d, unit is %d, unit offset is %d length %d\n", 
 			wc->num, chan->chanpos, chan->span->offset, unit, channel, eclen);
@@ -2308,6 +2330,53 @@ static void t4_vpm_set_dtmf_threshold(struct t4 *wc, unsigned int threshold)
 	printk("VPM: DTMF threshold set to %d\n", threshold);
 }
 
+static unsigned int t4_vpm_mask(int chip)
+{
+	unsigned int mask=0;
+	switch(vpmspans) {
+	case 4:
+		mask = 0x55555555 << (chip >> 2);
+		break;
+	case 2:
+		mask = 0x11111111 << (chip >> 1);
+		break;
+	case 1:
+		mask = 0x01010101 << chip;
+		break;
+	}
+	return mask;
+}
+
+static int t4_vpm_spanno(int chip)
+{
+	int spanno = 0;
+	switch(vpmspans) {
+	case 4:
+		spanno = chip & 0x3;
+		break;
+	case 2:
+		spanno = chip & 0x1;
+		break;
+	/* Case 1 is implicit */
+	}
+	return spanno;
+}
+
+static int t4_vpm_echotail(void)
+{
+	int echotail = 0x01ff;
+	switch(vpmspans) {
+	case 4:
+		echotail = 0x007f;
+		break;
+	case 2:
+		echotail = 0x00ff;
+		break;
+	/* Case 1 is implicit */
+	}
+	return echotail;
+}
+
 static void t4_vpm_init(struct t4 *wc)
 {
 	unsigned char reg;
@@ -2320,9 +2389,20 @@ static void t4_vpm_init(struct t4 *wc)
 		return;
 	}
 
+	switch(vpmspans) {
+	case 4:
+	case 2:
+	case 1:
+		break;
+	default:
+		printk("VPM: %d is not a valid vpmspans value, using 4\n", vpmspans);
+		vpmspans = 4;
+	}
+
 	for (x=0;x<8;x++) {
-		int spanno = x & 0x3;
+		int spanno = t4_vpm_spanno(x);
 		struct t4_span *ts = wc->tspans[spanno];
+		int echotail = t4_vpm_echotail();
 
 		ver = t4_vpm_in(wc, x, 0x1a0); /* revision */
 		if (ver != 0x26) {
@@ -2345,11 +2425,11 @@ static void t4_vpm_init(struct t4 *wc)
 		t4_vpm_out(wc, x, 0x02f, 0x20 | (spanno << 3)); 
 
 		/* Setup Echo length (128 taps) */
-		t4_vpm_out(wc, x, 0x022, 0x00);
-		t4_vpm_out(wc, x, 0x023, 0x7f);
+		t4_vpm_out(wc, x, 0x022, (echotail >> 8));
+		t4_vpm_out(wc, x, 0x023, (echotail & 0xff));
 		
 		/* Setup the tdm channel masks for all chips*/
-		mask = (x < 4) ? 0x55555555 : 0xaaaaaaaa;
+		mask = t4_vpm_mask(x);
 		for (i = 0; i < 4; i++)
 			t4_vpm_out(wc, x, 0x30 + i, (mask >> (i << 3)) & 0xff);
 
@@ -2357,11 +2437,11 @@ static void t4_vpm_init(struct t4 *wc)
 		reg = t4_vpm_in(wc,x,0x20);
 		reg &= 0xE0;
 		if (ts->spantype == TYPE_E1) {
-			if (x < 4)
+			if (x < vpmspans)
 				printk("VPM: Span %d A-law mode\n", spanno);
 			reg |= 0x01;
 		} else {
-			if (x < 4)
+			if (x < vpmspans)
 				printk("VPM: Span %d U-law mode\n", spanno);
 			reg &= ~0x01;
 		}
@@ -2391,7 +2471,7 @@ static void t4_vpm_init(struct t4 *wc)
 		/* set DTMF detection threshold */
 		t4_vpm_set_dtmf_threshold(wc, dtmfthreshold);
 
-		/* Enable DTMF detectors */
+		/* Enable DTMF detectors (always DTMF detect all spans) */
 		for (i = 0; i < MAX_DTMF_DET; i++) {
 			t4_vpm_out(wc, x, 0x98 + i, 0x40 | (i * 2) | ((x < 4) ? 0 : 1));
 		}
@@ -2401,7 +2481,7 @@ static void t4_vpm_init(struct t4 *wc)
 			t4_vpm_out(wc, x, i, (x < 4) ? 0x55 : 0xAA);
 
 	} 
-	printk("VPM: Present and operational\n");
+	printk("VPM: Present and operational servicing %d span(s)\n", vpmspans);
 	wc->vpm = T4_VPM_PRESENT;
 }
 
@@ -2885,6 +2965,7 @@ module_param(alarmdebounce, int, 0600);
 module_param(j1mode, int, 0600);
 #ifdef VPM_SUPPORT
 module_param(vpmsupport, int, 0600);
+module_param(vpmspans, int, 0600);
 module_param(dtmfthreshold, int, 0600);
 #endif
 #else
@@ -2899,6 +2980,7 @@ MODULE_PARM(alarmdebounce, "i");
 MODULE_PARM(j1mode, "i");
 #ifdef VPM_SUPPORT
 MODULE_PARM(vpmsupport, "i");
+MODULE_PARM(vpmspans, "i");
 MODULE_PARM(dtmfthreshold, "i");
 #endif
 #endif