[PATCH 6/8] ASoC: Intel: avs: Standby power-state support

[Cezary Rojewski <cezary.rojewski@xxxxxxxxx>]

From: Piotr Maziarz <piotrx.maziarz@xxxxxxxxxxxxxxx>

Introduce avs_suspend_standby() and avs_resume_standby() to support S0iX
streaming. The AudioDSP is not shutdown during such scenario and the PCI
device is armed for possible wake operation through an audio event.

Signed-off-by: Piotr Maziarz <piotrx.maziarz@xxxxxxxxxxxxxxx>
Signed-off-by: Cezary Rojewski <cezary.rojewski@xxxxxxxxx>
---
 sound/soc/intel/avs/core.c | 75 ++++++++++++++++++++++++++++++++++----
 1 file changed, 68 insertions(+), 7 deletions(-)

diff --git a/sound/soc/intel/avs/core.c b/sound/soc/intel/avs/core.c
index d067ce951afc..841bc9fa0d3b 100644
--- a/sound/soc/intel/avs/core.c
+++ b/sound/soc/intel/avs/core.c
@@ -534,12 +534,30 @@ static void avs_pci_remove(struct pci_dev *pci)
 	pm_runtime_get_noresume(&pci->dev);
 }
 
-static int __maybe_unused avs_suspend_common(struct avs_dev *adev)
+static int avs_suspend_standby(struct avs_dev *adev)
+{
+	struct hdac_bus *bus = &adev->base.core;
+	struct pci_dev *pci = adev->base.pci;
+
+	if (bus->cmd_dma_state)
+		snd_hdac_bus_stop_cmd_io(bus);
+
+	snd_hdac_ext_bus_link_power_down_all(bus);
+
+	enable_irq_wake(pci->irq);
+	pci_save_state(pci);
+
+	return 0;
+}
+
+static int __maybe_unused avs_suspend_common(struct avs_dev *adev, bool low_power)
 {
 	struct hdac_bus *bus = &adev->base.core;
 	int ret;
 
 	flush_work(&adev->probe_work);
+	if ((acpi_gbl_FADT.flags & ACPI_FADT_LOW_POWER_S0) && low_power && adev->num_lp_paths)
+		return avs_suspend_standby(adev);
 
 	snd_hdac_ext_bus_link_power_down_all(bus);
 
@@ -577,11 +595,30 @@ static int __maybe_unused avs_suspend_common(struct avs_dev *adev)
 	return 0;
 }
 
-static int __maybe_unused avs_resume_common(struct avs_dev *adev, bool purge)
+static int avs_resume_standby(struct avs_dev *adev)
+{
+	struct hdac_bus *bus = &adev->base.core;
+	struct pci_dev *pci = adev->base.pci;
+
+	pci_restore_state(pci);
+	disable_irq_wake(pci->irq);
+
+	snd_hdac_ext_bus_link_power_up_all(bus);
+
+	if (bus->cmd_dma_state)
+		snd_hdac_bus_init_cmd_io(bus);
+
+	return 0;
+}
+
+static int __maybe_unused avs_resume_common(struct avs_dev *adev, bool low_power, bool purge)
 {
 	struct hdac_bus *bus = &adev->base.core;
 	int ret;
 
+	if ((acpi_gbl_FADT.flags & ACPI_FADT_LOW_POWER_S0) && low_power && adev->num_lp_paths)
+		return avs_resume_standby(adev);
+
 	snd_hdac_display_power(bus, HDA_CODEC_IDX_CONTROLLER, true);
 	avs_hdac_bus_init_chip(bus, true);
 
@@ -599,26 +636,50 @@ static int __maybe_unused avs_resume_common(struct avs_dev *adev, bool purge)
 
 static int __maybe_unused avs_suspend(struct device *dev)
 {
-	return avs_suspend_common(to_avs_dev(dev));
+	return avs_suspend_common(to_avs_dev(dev), true);
 }
 
 static int __maybe_unused avs_resume(struct device *dev)
 {
-	return avs_resume_common(to_avs_dev(dev), true);
+	return avs_resume_common(to_avs_dev(dev), true, true);
 }
 
 static int __maybe_unused avs_runtime_suspend(struct device *dev)
 {
-	return avs_suspend_common(to_avs_dev(dev));
+	return avs_suspend_common(to_avs_dev(dev), true);
 }
 
 static int __maybe_unused avs_runtime_resume(struct device *dev)
 {
-	return avs_resume_common(to_avs_dev(dev), true);
+	return avs_resume_common(to_avs_dev(dev), true, false);
+}
+
+static int __maybe_unused avs_freeze(struct device *dev)
+{
+	return avs_suspend_common(to_avs_dev(dev), false);
+}
+static int __maybe_unused avs_thaw(struct device *dev)
+{
+	return avs_resume_common(to_avs_dev(dev), false, true);
+}
+
+static int __maybe_unused avs_poweroff(struct device *dev)
+{
+	return avs_suspend_common(to_avs_dev(dev), false);
+}
+
+static int __maybe_unused avs_restore(struct device *dev)
+{
+	return avs_resume_common(to_avs_dev(dev), false, true);
 }
 
 static const struct dev_pm_ops avs_dev_pm = {
-	SET_SYSTEM_SLEEP_PM_OPS(avs_suspend, avs_resume)
+	.suspend = avs_suspend,
+	.resume = avs_resume,
+	.freeze = avs_freeze,
+	.thaw = avs_thaw,
+	.poweroff = avs_poweroff,
+	.restore = avs_restore,
 	SET_RUNTIME_PM_OPS(avs_runtime_suspend, avs_runtime_resume, NULL)
 };
 
-- 
2.25.1