[alsa-devel] [PATCH] ALSA: hda - Fix DP-MST support for NVIDIA codecs

[Nikhil Mahale]

If dyn_pcm_assign is set, different jack objects are being created
for pcm and pins.

If dyn_pcm_assign is set, generic_hdmi_build_jack() calls into
add_hdmi_jack_kctl() to create and track separate jack object for
pcm. Like sync_eld_via_acomp(), hdmi_present_sense_via_verbs() also
need to report status change of the pcm jack.

Rename pin_idx_to_jack() to pin_idx_to_pcm_jack(). Update
hdmi_present_sense_via_verbs() to report plug state of pcm jack
object. Unlike sync_eld_via_acomp(), for !acomp drivers the pcm
jack's plug state must be consistent with plug state
of pin's jack.

Fixes: 5398e94fb753 ("ALSA: hda - Add DP-MST support for NVIDIA codecs")
Signed-off-by: Nikhil Mahale <nmahale at nvidia.com>
---
 sound/pci/hda/patch_hdmi.c | 94 +++++++++++++++++++++++++++++++---------------
 1 file changed, 63 insertions(+), 31 deletions(-)

diff --git a/sound/pci/hda/patch_hdmi.c b/sound/pci/hda/patch_hdmi.c
index 48bddc218829..c1d3ce423142 100644
--- a/sound/pci/hda/patch_hdmi.c
+++ b/sound/pci/hda/patch_hdmi.c
@@ -1550,6 +1550,34 @@ static bool update_eld(struct hda_codec *codec,
 	return eld_changed;
 }
 
+static struct snd_jack *pin_idx_to_pcm_jack(struct hda_codec *codec,
+					    struct hdmi_spec_per_pin *per_pin)
+{
+	struct hdmi_spec *spec = codec->spec;
+	struct snd_jack *jack = NULL;
+	struct hda_jack_tbl *jack_tbl;
+
+	/* if !dyn_pcm_assign, get jack from hda_jack_tbl
+	 * in !dyn_pcm_assign case, spec->pcm_rec[].jack is not
+	 * NULL even after snd_hda_jack_tbl_clear() is called to
+	 * free snd_jack. This may cause access invalid memory
+	 * when calling snd_jack_report
+	 */
+	if (per_pin->pcm_idx >= 0 && spec->dyn_pcm_assign) {
+		jack = spec->pcm_rec[per_pin->pcm_idx].jack;
+	} else if (!spec->dyn_pcm_assign) {
+		/*
+		 * jack tbl doesn't support DP MST
+		 * DP MST will use dyn_pcm_assign,
+		 * so DP MST will never come here
+		 */
+		jack_tbl = snd_hda_jack_tbl_get_mst(codec, per_pin->pin_nid,
+						    per_pin->dev_id);
+		if (jack_tbl)
+			jack = jack_tbl->jack;
+	}
+	return jack;
+}
 /* update ELD and jack state via HD-audio verbs */
 static bool hdmi_present_sense_via_verbs(struct hdmi_spec_per_pin *per_pin,
 					 int repoll)
@@ -1571,6 +1599,7 @@ static bool hdmi_present_sense_via_verbs(struct hdmi_spec_per_pin *per_pin,
 	int present;
 	bool ret;
 	bool do_repoll = false;
+	struct snd_jack *pcm_jack = NULL;
 
 	present = snd_hda_jack_pin_sense(codec, pin_nid, dev_id);
 
@@ -1598,10 +1627,19 @@ static bool hdmi_present_sense_via_verbs(struct hdmi_spec_per_pin *per_pin,
 			do_repoll = true;
 	}
 
-	if (do_repoll)
+	if (do_repoll) {
 		schedule_delayed_work(&per_pin->work, msecs_to_jiffies(300));
-	else
+	} else {
+		/*
+		 * pcm_idx >=0 before update_eld() means it is in monitor
+		 * disconnected event. Jack must be fetched before
+		 * update_eld().
+		 */
+		pcm_jack = pin_idx_to_pcm_jack(codec, per_pin);
 		update_eld(codec, per_pin, eld);
+		if (!pcm_jack)
+			pcm_jack = pin_idx_to_pcm_jack(codec, per_pin);
+	}
 
 	ret = !repoll || !eld->monitor_present || eld->eld_valid;
 
@@ -1610,38 +1648,32 @@ static bool hdmi_present_sense_via_verbs(struct hdmi_spec_per_pin *per_pin,
 		jack->block_report = !ret;
 		jack->pin_sense = (eld->monitor_present && eld->eld_valid) ?
 			AC_PINSENSE_PRESENCE : 0;
-	}
-	mutex_unlock(&per_pin->lock);
-	return ret;
-}
 
-static struct snd_jack *pin_idx_to_jack(struct hda_codec *codec,
-				 struct hdmi_spec_per_pin *per_pin)
-{
-	struct hdmi_spec *spec = codec->spec;
-	struct snd_jack *jack = NULL;
-	struct hda_jack_tbl *jack_tbl;
+		if (spec->dyn_pcm_assign && pcm_jack && !do_repoll) {
+			int state = 0;
+
+			if (!!(jack->pin_sense & AC_PINSENSE_PRESENCE))
+				state = SND_JACK_AVOUT;
+			snd_jack_report(pcm_jack, state);
+		}
 
-	/* if !dyn_pcm_assign, get jack from hda_jack_tbl
-	 * in !dyn_pcm_assign case, spec->pcm_rec[].jack is not
-	 * NULL even after snd_hda_jack_tbl_clear() is called to
-	 * free snd_jack. This may cause access invalid memory
-	 * when calling snd_jack_report
-	 */
-	if (per_pin->pcm_idx >= 0 && spec->dyn_pcm_assign)
-		jack = spec->pcm_rec[per_pin->pcm_idx].jack;
-	else if (!spec->dyn_pcm_assign) {
 		/*
-		 * jack tbl doesn't support DP MST
-		 * DP MST will use dyn_pcm_assign,
-		 * so DP MST will never come here
+		 * snd_hda_jack_pin_sense() call at the beginning of this
+		 * function, updates jack->pins_sense and clears
+		 * jack->jack_dirty, therefore snd_hda_jack_report_sync() will
+		 * not override the jack->pin_sense.
+		 *
+		 * snd_hda_jack_report_sync() is superfluous for dyn_pcm_assign
+		 * case. The jack->pin_sense update was already performed, and
+		 * hda_jack->jack is NULL for dyn_pcm_assign.
+		 *
+		 * Don't call snd_hda_jack_report_sync() for
+		 * dyn_pcm_assign.
 		 */
-		jack_tbl = snd_hda_jack_tbl_get_mst(codec, per_pin->pin_nid,
-						    per_pin->dev_id);
-		if (jack_tbl)
-			jack = jack_tbl->jack;
+		ret = ret && !spec->dyn_pcm_assign;
 	}
-	return jack;
+	mutex_unlock(&per_pin->lock);
+	return ret;
 }
 
 /* update ELD and jack state via audio component */
@@ -1677,10 +1709,10 @@ static void sync_eld_via_acomp(struct hda_codec *codec,
 	/* pcm_idx >=0 before update_eld() means it is in monitor
 	 * disconnected event. Jack must be fetched before update_eld()
 	 */
-	jack = pin_idx_to_jack(codec, per_pin);
+	jack = pin_idx_to_pcm_jack(codec, per_pin);
 	changed = update_eld(codec, per_pin, eld);
 	if (jack == NULL)
-		jack = pin_idx_to_jack(codec, per_pin);
+		jack = pin_idx_to_pcm_jack(codec, per_pin);
 	if (changed && jack)
 		snd_jack_report(jack,
 				(eld->monitor_present && eld->eld_valid) ?
-- 
2.16.4