[alsa-devel] [RFC PATCH] ALSA : hda - not use assigned converters for all unused pins

[mengdong.lin at intel.com]

From: Mengdong Lin <mengdong.lin at intel.com>

BIOS can mark a pin as "no physical connection" if the port is used by an
integrated display which is not audio capable. And audio driver will overlook
such pins.

On Haswell, such a disconneted pin will keep muted and connected to the 1st
converter by default. But if the 1st convertor is assigned to a connected pin
for audio streaming. The muted disconnected pin can make the connected pin
no sound output.

So this patch avoids using assigned converters for all unused pins for Haswell,
including the disconected pins.

Signed-off-by: Mengdong Lin <mengdong.lin at intel.com>

diff --git a/sound/pci/hda/patch_hdmi.c b/sound/pci/hda/patch_hdmi.c
index 3d8cd044..4960695 100644
--- a/sound/pci/hda/patch_hdmi.c
+++ b/sound/pci/hda/patch_hdmi.c
@@ -1152,29 +1152,34 @@ static void haswell_config_cvts(struct hda_codec *codec,
 			int pin_id, int mux_id)
 {
 	struct hdmi_spec *spec = codec->spec;
-	struct hdmi_spec_per_pin *per_pin;
-	int pin_idx, mux_idx;
+	hda_nid_t  pin_nid;
+	int pin_idx, cvt_idx;
 	int curr;
-	int err;
-
-	for (pin_idx = 0; pin_idx < spec->num_pins; pin_idx++) {
-		per_pin = get_pin(spec, pin_idx);
+	struct hdmi_spec_per_cvt *per_cvt;
 
+	/* configure all 3 pins, including "no physical connection" ones */
+	for (pin_nid = 5; pin_nid < 8; pin_nid++) {
+		pin_idx = pin_nid_to_pin_index(spec, pin_nid);
 		if (pin_idx == pin_id)
 			continue;
 
-		curr = snd_hda_codec_read(codec, per_pin->pin_nid, 0,
+		curr = snd_hda_codec_read(codec, pin_nid, 0,
 					  AC_VERB_GET_CONNECT_SEL, 0);
+		if (curr != mux_id)
+			continue;
+
+		for (cvt_idx = 0; cvt_idx < spec->num_cvts; cvt_idx++) {
+			per_cvt = get_cvt(spec, cvt_idx);
 
-		/* Choose another unused converter */
-		if (curr == mux_id) {
-			err = hdmi_choose_cvt(codec, pin_idx, NULL, &mux_idx);
-			if (err < 0)
-				return;
-			snd_printdd("HDMI: choose converter %d for pin %d\n", mux_idx, pin_idx);
-			snd_hda_codec_write_cache(codec, per_pin->pin_nid, 0,
+			/* Must not already be assigned */
+			if (!per_cvt->assigned) {
+				snd_printdd("choose converter %d for pin %d\n",
+					cvt_idx, pin_idx);
+				snd_hda_codec_write_cache(codec, pin_nid, 0,
 					    AC_VERB_SET_CONNECT_SEL,
-					    mux_idx);
+					    cvt_idx);
+				break;
+			}
 		}
 	}
 }
-- 
1.8.1.2