- try to identify a "main input mixer"

- don't unmute input from a built-in mic on the main input mixer
intended to stop possible feedback loops between buit-in speakers
and built-in mics.  built-in mics also tend to capture machine
noise, especially fans.  actual recording should not be affected.

3 files changed, 58 insertions, 3 deletions

diff --git a/sys/dev/pci/azalia.c b/sys/dev/pci/azalia.c
index a31bc21133a..ff7f296f1ad 100644
--- a/sys/dev/pci/azalia.c
+++ b/sys/dev/pci/azalia.c
@@ -1,4 +1,4 @@
-/*	$OpenBSD: azalia.c,v 1.130 2009/05/01 04:00:40 jakemsr Exp $	*/
+/*	$OpenBSD: azalia.c,v 1.131 2009/05/12 09:32:28 jakemsr Exp $	*/
 /*	$NetBSD: azalia.c,v 1.20 2006/05/07 08:31:44 kent Exp $	*/
 
 /*-
@@ -213,6 +213,7 @@ int	azalia_codec_init_volgroups(codec_t *);
 int	azalia_codec_sort_pins(codec_t *);
 int	azalia_codec_select_micadc(codec_t *);
 int	azalia_codec_select_spkrdac(codec_t *);
+int	azalia_codec_find_inputmixer(codec_t *);
 
 int	azalia_widget_init(widget_t *, const codec_t *, int);
 int	azalia_widget_label_widgets(codec_t *);
@@ -1356,6 +1357,10 @@ azalia_codec_init(codec_t *this)
 	if (err)
 		return err;
 
+	err = azalia_codec_find_inputmixer(this);
+	if (err)
+		return err;
+
 	err = azalia_codec_select_spkrdac(this);
 	if (err)
 		return err;
@@ -1390,6 +1395,52 @@ azalia_codec_init(codec_t *this)
 }
 
 int
+azalia_codec_find_inputmixer(codec_t *this)
+{
+	widget_t *w;
+	int i, j;
+
+	this->input_mixer = -1;
+
+	FOR_EACH_WIDGET(this, i) {
+		w = &this->w[i];
+		if (w->type != COP_AWTYPE_AUDIO_MIXER)
+			continue;
+
+		/* can input from a pin */
+		for (j = 0; j < this->nipins; j++) {
+			if (azalia_codec_fnode(this, this->ipins[j].nid,
+			    w->nid, 0) != -1)
+				break;
+		}
+		if (j == this->nipins)
+			continue;
+
+		/* can output to a pin */
+		for (j = 0; j < this->nopins; j++) {
+			if (azalia_codec_fnode(this, w->nid,
+			    this->opins[j].nid, 0) != -1)
+				break;
+		}
+		if (j == this->nopins)
+			continue;
+
+		/* can output to an ADC */
+		for (j = 0; j < this->na_adcs; j++) {
+			if (azalia_codec_fnode(this, w->nid,
+			    this->a_adcs[j], 0) != -1)
+				break;
+		}
+		if (j == this->na_adcs)
+			continue;
+
+		this->input_mixer = i;
+		break;
+	}
+	return(0);
+}
+
+int
 azalia_codec_select_micadc(codec_t *this)
 {
 	widget_t *w;
diff --git a/sys/dev/pci/azalia.h b/sys/dev/pci/azalia.h
index 42780cf1806..52d3fafab3b 100644
--- a/sys/dev/pci/azalia.h
+++ b/sys/dev/pci/azalia.h
@@ -1,4 +1,4 @@
-/*	$OpenBSD: azalia.h,v 1.44 2009/05/01 02:55:16 jakemsr Exp $	*/
+/*	$OpenBSD: azalia.h,v 1.45 2009/05/12 09:32:28 jakemsr Exp $	*/
 /*	$NetBSD: azalia.h,v 1.6 2006/01/16 14:15:26 kent Exp $	*/
 
 /*-
@@ -668,6 +668,7 @@ typedef struct codec_t {
 	nid_t mic_adc;
 	nid_t speaker;		/* fixed (internal) speaker */
 	nid_t spkr_dac;
+	nid_t input_mixer;
 
 	int spkr_muters;
 	int spkr_mute_method;
diff --git a/sys/dev/pci/azalia_codec.c b/sys/dev/pci/azalia_codec.c
index 81035c6e932..7480ac9cd44 100644
--- a/sys/dev/pci/azalia_codec.c
+++ b/sys/dev/pci/azalia_codec.c
@@ -1,4 +1,4 @@
-/*	$OpenBSD: azalia_codec.c,v 1.122 2009/05/01 03:45:17 jakemsr Exp $	*/
+/*	$OpenBSD: azalia_codec.c,v 1.123 2009/05/12 09:32:28 jakemsr Exp $	*/
 /*	$NetBSD: azalia_codec.c,v 1.8 2006/05/10 11:17:27 kent Exp $	*/
 
 /*-
@@ -1278,6 +1278,9 @@ azalia_generic_mixer_default(codec_t *this)
 		for (j = 0; j < w->nconnections; j++) {
 			if (!azalia_widget_enabled(this, w->connections[j]))
 				continue;
+			if (w->nid == this->input_mixer &&
+			    w->connections[j] == this->mic)
+				continue;
 			mc.un.mask |= 1 << j;
 		}
 		azalia_generic_mixer_set(this, m->nid, m->target, &mc);