ASoC: SOF: pm: Fix prepare callback behavior for OF usecase

On i.MX platforms PM is not managed via ACPI although CONFIG_ACPI
can be set. So, in order to correctly set the system target state
we introduce a flag for platforms that require to use acpi target
states.
Signed-off-by: Daniel Baluta <daniel.baluta@nxp.com>
Reviewed-by: Pierre-Louis Bossart <pierre-louis.bossart@linux.intel.com>
Reviewed-by: Ranjani Sridharan <ranjani.sridharan@linux.intel.com>
Signed-off-by: Kai Vehmanen <kai.vehmanen@linux.intel.com>
Link: https://lore.kernel.org/r/20200921105038.2909899-1-kai.vehmanen@linux.intel.comSigned-off-by: Mark Brown <broonie@kernel.org>

include/sound/sof.h

@@ -66,6 +66,8 @@ struct sof_dev_desc {
 	/* alternate list of machines using this configuration */
 	struct snd_soc_acpi_mach *alt_machines;
 
+	bool use_acpi_target_states;
+
 	/* Platform resource indexes in BAR / ACPI resources. */
 	/* Must set to -1 if not used - add new items to end */
 	int resindex_lpe_base;

sound/soc/sof/pm.c

@@ -305,15 +305,17 @@ EXPORT_SYMBOL(snd_sof_suspend);
 int snd_sof_prepare(struct device *dev)
 {
 	struct snd_sof_dev *sdev = dev_get_drvdata(dev);
+	const struct sof_dev_desc *desc = sdev->pdata->desc;
+
+	/* will suspend to S3 by default */
+	sdev->system_suspend_target = SOF_SUSPEND_S3;
+
+	if (!desc->use_acpi_target_states)
+		return 0;
 
 #if defined(CONFIG_ACPI)
 	if (acpi_target_system_state() == ACPI_STATE_S0)
 		sdev->system_suspend_target = SOF_SUSPEND_S0IX;
-	else
-		sdev->system_suspend_target = SOF_SUSPEND_S3;
-#else
-	/* will suspend to S3 by default */
-	sdev->system_suspend_target = SOF_SUSPEND_S3;
 #endif
 
 	return 0;

sound/soc/sof/sof-pci-dev.c

@@ -77,6 +77,7 @@ static const struct dmi_system_id community_key_platforms[] = {
 #if IS_ENABLED(CONFIG_SND_SOC_SOF_APOLLOLAKE)
 static const struct sof_dev_desc bxt_desc = {
 	.machines		= snd_soc_acpi_intel_bxt_machines,
+	.use_acpi_target_states	= true,
 	.resindex_lpe_base	= 0,
 	.resindex_pcicfg_base	= -1,
 	.resindex_imr_base	= -1,
@@ -94,6 +95,7 @@ static const struct sof_dev_desc bxt_desc = {
 #if IS_ENABLED(CONFIG_SND_SOC_SOF_GEMINILAKE)
 static const struct sof_dev_desc glk_desc = {
 	.machines		= snd_soc_acpi_intel_glk_machines,
+	.use_acpi_target_states	= true,
 	.resindex_lpe_base	= 0,
 	.resindex_pcicfg_base	= -1,
 	.resindex_imr_base	= -1,
@@ -139,6 +141,7 @@ static const struct sof_dev_desc tng_desc = {
 static const struct sof_dev_desc cnl_desc = {
 	.machines		= snd_soc_acpi_intel_cnl_machines,
 	.alt_machines		= snd_soc_acpi_intel_cnl_sdw_machines,
+	.use_acpi_target_states	= true,
 	.resindex_lpe_base	= 0,
 	.resindex_pcicfg_base	= -1,
 	.resindex_imr_base	= -1,
@@ -157,6 +160,7 @@ static const struct sof_dev_desc cnl_desc = {
 static const struct sof_dev_desc cfl_desc = {
 	.machines		= snd_soc_acpi_intel_cfl_machines,
 	.alt_machines		= snd_soc_acpi_intel_cfl_sdw_machines,
+	.use_acpi_target_states	= true,
 	.resindex_lpe_base	= 0,
 	.resindex_pcicfg_base	= -1,
 	.resindex_imr_base	= -1,
@@ -175,6 +179,7 @@ static const struct sof_dev_desc cfl_desc = {
 static const struct sof_dev_desc cml_desc = {
 	.machines		= snd_soc_acpi_intel_cml_machines,
 	.alt_machines		= snd_soc_acpi_intel_cml_sdw_machines,
+	.use_acpi_target_states	= true,
 	.resindex_lpe_base	= 0,
 	.resindex_pcicfg_base	= -1,
 	.resindex_imr_base	= -1,
@@ -193,6 +198,7 @@ static const struct sof_dev_desc cml_desc = {
 static const struct sof_dev_desc icl_desc = {
 	.machines               = snd_soc_acpi_intel_icl_machines,
 	.alt_machines		= snd_soc_acpi_intel_icl_sdw_machines,
+	.use_acpi_target_states	= true,
 	.resindex_lpe_base      = 0,
 	.resindex_pcicfg_base   = -1,
 	.resindex_imr_base      = -1,
@@ -211,6 +217,7 @@ static const struct sof_dev_desc icl_desc = {
 static const struct sof_dev_desc tgl_desc = {
 	.machines               = snd_soc_acpi_intel_tgl_machines,
 	.alt_machines		= snd_soc_acpi_intel_tgl_sdw_machines,
+	.use_acpi_target_states	= true,
 	.resindex_lpe_base      = 0,
 	.resindex_pcicfg_base   = -1,
 	.resindex_imr_base      = -1,
@@ -244,6 +251,7 @@ static const struct sof_dev_desc tglh_desc = {
 #if IS_ENABLED(CONFIG_SND_SOC_SOF_ELKHARTLAKE)
 static const struct sof_dev_desc ehl_desc = {
 	.machines               = snd_soc_acpi_intel_ehl_machines,
+	.use_acpi_target_states	= true,
 	.resindex_lpe_base      = 0,
 	.resindex_pcicfg_base   = -1,
 	.resindex_imr_base      = -1,
@@ -261,6 +269,7 @@ static const struct sof_dev_desc ehl_desc = {
 #if IS_ENABLED(CONFIG_SND_SOC_SOF_JASPERLAKE)
 static const struct sof_dev_desc jsl_desc = {
 	.machines               = snd_soc_acpi_intel_jsl_machines,
+	.use_acpi_target_states	= true,
 	.resindex_lpe_base      = 0,
 	.resindex_pcicfg_base   = -1,
 	.resindex_imr_base      = -1,