[PATCH 5/5] ALSA: hda/tas2781: restore power state after system_resume

[Gergo Koteles <soyer@xxxxxx>]

After system_resume the amplifers will remain off, even if they were on
before system_suspend.

Use playback_started bool to save the playback state, and restore power
state based on it.

Fixes: 5be27f1e3ec9 ("ALSA: hda/tas2781: Add tas2781 HDA driver")
Signed-off-by: Gergo Koteles <soyer@xxxxxx>
---
 sound/pci/hda/tas2781_hda_i2c.c | 13 ++++++++++++-
 1 file changed, 12 insertions(+), 1 deletion(-)

diff --git a/sound/pci/hda/tas2781_hda_i2c.c b/sound/pci/hda/tas2781_hda_i2c.c
index a99f490c6a23..7aef93126ed0 100644
--- a/sound/pci/hda/tas2781_hda_i2c.c
+++ b/sound/pci/hda/tas2781_hda_i2c.c
@@ -160,11 +160,13 @@ static void tas2781_hda_playback_hook(struct device *dev, int action)
 		pm_runtime_get_sync(dev);
 		mutex_lock(&tas_hda->priv->codec_lock);
 		tasdevice_tuning_switch(tas_hda->priv, 0);
+		tas_hda->priv->playback_started = true;
 		mutex_unlock(&tas_hda->priv->codec_lock);
 		break;
 	case HDA_GEN_PCM_ACT_CLOSE:
 		mutex_lock(&tas_hda->priv->codec_lock);
 		tasdevice_tuning_switch(tas_hda->priv, 1);
+		tas_hda->priv->playback_started = false;
 		mutex_unlock(&tas_hda->priv->codec_lock);
 
 		pm_runtime_mark_last_busy(dev);
@@ -666,6 +668,7 @@ static void tasdev_fw_ready(const struct firmware *fmw, void *context)
 	tasdevice_save_calibration(tas_priv);
 
 	tasdevice_tuning_switch(tas_hda->priv, 0);
+	tas_hda->priv->playback_started = true;
 
 out:
 	mutex_unlock(&tas_hda->priv->codec_lock);
@@ -837,6 +840,9 @@ static int tas2781_runtime_suspend(struct device *dev)
 
 	mutex_lock(&tas_hda->priv->codec_lock);
 
+	/* The driver powers up the amplifiers at module load time.
+	 * Stop the playback if it's unused.
+	 */
 	if (tas_hda->priv->playback_started) {
 		tasdevice_tuning_switch(tas_hda->priv, 1);
 		tas_hda->priv->playback_started = false;
@@ -876,7 +882,8 @@ static int tas2781_system_suspend(struct device *dev)
 	mutex_lock(&tas_hda->priv->codec_lock);
 
 	/* Shutdown chip before system suspend */
-	tasdevice_tuning_switch(tas_hda->priv, 1);
+	if (tas_hda->priv->playback_started)
+		tasdevice_tuning_switch(tas_hda->priv, 1);
 
 	mutex_unlock(&tas_hda->priv->codec_lock);
 
@@ -908,6 +915,10 @@ static int tas2781_system_resume(struct device *dev)
 	 * calibrated data inside algo.
 	 */
 	tasdevice_apply_calibration(tas_hda->priv);
+
+	if (tas_hda->priv->playback_started)
+		tasdevice_tuning_switch(tas_hda->priv, 0);
+
 	mutex_unlock(&tas_hda->priv->codec_lock);
 
 	return 0;
-- 
2.44.0