[alsa-devel] [PATCH 3/3] ALSA: hda - hdmi: Notify userspace when ELD control changes

[David Henningsson]

Since ELD sometimes becomes available a while after we have detected
presence, we need to be able to listen for changes on the ELD control.

Signed-off-by: David Henningsson <david.henningsson at canonical.com>
---
 sound/pci/hda/patch_hdmi.c |   10 ++++++++++
 1 file changed, 10 insertions(+)

diff --git a/sound/pci/hda/patch_hdmi.c b/sound/pci/hda/patch_hdmi.c
index 9236cdb..d3b1a93 100644
--- a/sound/pci/hda/patch_hdmi.c
+++ b/sound/pci/hda/patch_hdmi.c
@@ -74,6 +74,7 @@ struct hdmi_spec_per_pin {
 
 	struct hda_codec *codec;
 	struct hdmi_eld sink_eld;
+	struct snd_kcontrol *eld_ctl;
 	struct delayed_work work;
 	int repoll_count;
 	bool non_pcm;
@@ -406,6 +407,7 @@ static int hdmi_create_eld_ctl(struct hda_codec *codec, int pin_idx,
 	if (err < 0)
 		return err;
 
+	spec->pins[pin_idx].eld_ctl = kctl;
 	return 0;
 }
 
@@ -1175,6 +1177,7 @@ static void hdmi_present_sense(struct hdmi_spec_per_pin *per_pin, int repoll)
 	 */
 	int present = snd_hda_pin_sense(codec, pin_nid);
 	bool eld_valid = false;
+	bool old_eld_valid = eld->eld_valid;
 
 	memset(eld, 0, offsetof(struct hdmi_eld, eld_buffer));
 
@@ -1196,6 +1199,13 @@ static void hdmi_present_sense(struct hdmi_spec_per_pin *per_pin, int repoll)
 					   msecs_to_jiffies(300));
 		}
 	}
+
+	if (eld->eld_valid != old_eld_valid && per_pin->eld_ctl) {
+		snd_ctl_notify(codec->bus->card,
+			       SNDRV_CTL_EVENT_MASK_VALUE | SNDRV_CTL_EVENT_MASK_INFO,
+			       &per_pin->eld_ctl->id);
+	}
+
 }
 
 static void hdmi_repoll_eld(struct work_struct *work)
-- 
1.7.9.5