ASoC: SOF: Intel: implement runtime idle for CNL/APL

Implement runtime idle for CNL/APL devices using similar runtime
PM idle logic as the Intel AZX HDA driver. If any HDA codecs are
powered when runtime suspend request comes, return -EBUSY. By doing
this, strict ordering is enforced between HDA codec and the HDA
controller.
Signed-off-by: Kai Vehmanen <kai.vehmanen@linux.intel.com>
Reviewed-by: Pierre-Louis Bossart <pierre-louis.bossart@linux.intel.com>
Reviewed-by: Takashi Iwai <tiwai@suse.de>
Link: https://lore.kernel.org/r/20190702132428.13129-4-kai.vehmanen@linux.intel.comSigned-off-by: Mark Brown <broonie@kernel.org>

sound/soc/sof/intel/apl.c

@@ -93,6 +93,7 @@ const struct snd_sof_dsp_ops sof_apl_ops = {
 	.resume			= hda_dsp_resume,
 	.runtime_suspend	= hda_dsp_runtime_suspend,
 	.runtime_resume		= hda_dsp_runtime_resume,
+	.runtime_idle		= hda_dsp_runtime_idle,
 	.set_hw_params_upon_resume = hda_dsp_set_hw_params_upon_resume,
 };
 EXPORT_SYMBOL(sof_apl_ops);

sound/soc/sof/intel/cnl.c

@@ -251,6 +251,7 @@ const struct snd_sof_dsp_ops sof_cnl_ops = {
 	.resume			= hda_dsp_resume,
 	.runtime_suspend	= hda_dsp_runtime_suspend,
 	.runtime_resume		= hda_dsp_runtime_resume,
+	.runtime_idle		= hda_dsp_runtime_idle,
 	.set_hw_params_upon_resume = hda_dsp_set_hw_params_upon_resume,
 };
 EXPORT_SYMBOL(sof_cnl_ops);

sound/soc/sof/intel/hda-dsp.c

@@ -418,6 +418,19 @@ int hda_dsp_runtime_resume(struct snd_sof_dev *sdev)
 	return hda_resume(sdev);
 }
 
+int hda_dsp_runtime_idle(struct snd_sof_dev *sdev)
+{
+	struct hdac_bus *hbus = sof_to_bus(sdev);
+
+	if (hbus->codec_powered) {
+		dev_dbg(sdev->dev, "some codecs still powered (%08X), not idle\n",
+			(unsigned int)hbus->codec_powered);
+		return -EBUSY;
+	}
+
+	return 0;
+}
+
 int hda_dsp_runtime_suspend(struct snd_sof_dev *sdev, int state)
 {
 	/* stop hda controller and power dsp off */