ASoC: hdmi-codec: Get ELD in before reporting plugged event

In plugged callback, ELD should be updated from display driver so that
user space can query information from ELD immediately after receiving jack
plugged event.

When jack is unplugged, clear ELD buffer so that user space does not get
obsolete information of unplugged HDMI.
Signed-off-by: Cheng-Yi Chiang <cychiang@chromium.org>
Link: https://lore.kernel.org/r/20201118043852.1338877-1-cychiang@chromium.orgSigned-off-by: Mark Brown <broonie@kernel.org>

sound/soc/codecs/hdmi-codec.c

@@ -692,10 +692,16 @@ static void plugged_cb(struct device *dev, bool plugged)
 {
 	struct hdmi_codec_priv *hcp = dev_get_drvdata(dev);
 
-	if (plugged)
+	if (plugged) {
+		if (hcp->hcd.ops->get_eld) {
+			hcp->hcd.ops->get_eld(dev->parent, hcp->hcd.data,
+					    hcp->eld, sizeof(hcp->eld));
+		}
 		hdmi_codec_jack_report(hcp, SND_JACK_LINEOUT);
-	else
+	} else {
 		hdmi_codec_jack_report(hcp, 0);
+		memset(hcp->eld, 0, sizeof(hcp->eld));
+	}
 }
 
 static int hdmi_codec_set_jack(struct snd_soc_component *component,