ASoC: hdac_hdmi: Add PM support

The codec registers are reset during S3. So need to reconfigure
all pins and DP1.2 feature again after resume from S3. Also
reprogram the required registers if the S3 was triggered during
playback.

In suspended state ELD notify callback is not processed, So add
ELD check for all pins as well.

Also turn the codec power domain OFF which is kept ON during
controller resequencing and codec reenumeration.

Signed-off-by: Jeeja KP <jeeja.kp@intel.com>
Signed-off-by: Subhransu S. Prusty <subhransu.s.prusty@intel.com>
Signed-off-by: Vinod Koul <vinod.koul@intel.com>
Signed-off-by: Mark Brown <broonie@kernel.org>

sound/soc/codecs/hdac_hdmi.c

@@ -601,6 +601,26 @@ static int hdac_hdmi_pcm_open(struct snd_pcm_substream *substream,
 				pin->eld.eld_buffer);
 }
 
+static int hdac_hdmi_trigger(struct snd_pcm_substream *substream, int cmd,
+		struct snd_soc_dai *dai)
+{
+	struct hdac_hdmi_dai_pin_map *dai_map;
+	struct hdac_ext_device *hdac = snd_soc_dai_get_drvdata(dai);
+	struct hdac_hdmi_priv *hdmi = hdac->private_data;
+	int ret;
+
+	dai_map = &hdmi->dai_map[dai->id];
+	if (cmd == SNDRV_PCM_TRIGGER_RESUME) {
+		ret = hdac_hdmi_enable_pin(hdac, dai_map);
+		if (ret < 0)
+			return ret;
+
+		return hdac_hdmi_playback_prepare(substream, dai);
+	}
+
+	return 0;
+}
+
 static void hdac_hdmi_pcm_close(struct snd_pcm_substream *substream,
 		struct snd_soc_dai *dai)
 {
@@ -1154,6 +1174,7 @@ static struct snd_soc_dai_ops hdmi_dai_ops = {
 	.shutdown = hdac_hdmi_pcm_close,
 	.hw_params = hdac_hdmi_set_hw_params,
 	.prepare = hdac_hdmi_playback_prepare,
+	.trigger = hdac_hdmi_trigger,
 	.hw_free = hdac_hdmi_playback_cleanup,
 };
 
@@ -1399,9 +1420,64 @@ static int hdmi_codec_remove(struct snd_soc_codec *codec)
 	return 0;
 }
 
+#ifdef CONFIG_PM
+static int hdmi_codec_resume(struct snd_soc_codec *codec)
+{
+	struct hdac_ext_device *edev = snd_soc_codec_get_drvdata(codec);
+	struct hdac_hdmi_priv *hdmi = edev->private_data;
+	struct hdac_hdmi_pin *pin;
+	struct hdac_device *hdac = &edev->hdac;
+	struct hdac_bus *bus = hdac->bus;
+	int err;
+	unsigned long timeout;
+
+	hdac_hdmi_skl_enable_all_pins(&edev->hdac);
+	hdac_hdmi_skl_enable_dp12(&edev->hdac);
+
+	/* Power up afg */
+	if (!snd_hdac_check_power_state(hdac, hdac->afg, AC_PWRST_D0)) {
+
+		snd_hdac_codec_write(hdac, hdac->afg, 0,
+			AC_VERB_SET_POWER_STATE, AC_PWRST_D0);
+
+		/* Wait till power state is set to D0 */
+		timeout = jiffies + msecs_to_jiffies(1000);
+		while (!snd_hdac_check_power_state(hdac, hdac->afg, AC_PWRST_D0)
+				&& time_before(jiffies, timeout)) {
+			msleep(50);
+		}
+	}
+
+	/*
+	 * As the ELD notify callback request is not entertained while the
+	 * device is in suspend state. Need to manually check detection of
+	 * all pins here.
+	 */
+	list_for_each_entry(pin, &hdmi->pin_list, head)
+		hdac_hdmi_present_sense(pin, 1);
+
+	/*
+	 * Codec power is turned ON during controller resume.
+	 * Turn it OFF here
+	 */
+	err = snd_hdac_display_power(bus, false);
+	if (err < 0) {
+		dev_err(bus->dev,
+			"Cannot turn OFF display power on i915, err: %d\n",
+			err);
+		return err;
+	}
+
+	return 0;
+}
+#else
+#define hdmi_codec_resume NULL
+#endif
+
 static struct snd_soc_codec_driver hdmi_hda_codec = {
 	.probe		= hdmi_codec_probe,
 	.remove		= hdmi_codec_remove,
+	.resume		= hdmi_codec_resume,
 	.idle_bias_off	= true,
 };