ASoC: Intel: sst: add runtime power management handling

This patch adds the runtime pm handlers, the driver already has code for
get/put for runtime pm and only these handlers being missing.
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/intel/sst/sst.c

@@ -152,6 +152,23 @@ static irqreturn_t intel_sst_irq_thread_mrfld(int irq, void *context)
 	return IRQ_HANDLED;
 }
 
+static int sst_save_dsp_context_v2(struct intel_sst_drv *sst)
+{
+	int ret = 0;
+
+	ret = sst_prepare_and_post_msg(sst, SST_TASK_ID_MEDIA, IPC_CMD,
+			IPC_PREP_D3, PIPE_RSVD, 0, NULL, NULL,
+			true, true, false, true);
+
+	if (ret < 0) {
+		dev_err(sst->dev, "not suspending FW!!, Err: %d\n", ret);
+		return -EIO;
+	}
+
+	return 0;
+}
+
+
 static struct intel_sst_ops mrfld_ops = {
 	.interrupt = intel_sst_interrupt_mrfld,
 	.irq_thread = intel_sst_irq_thread_mrfld,
@@ -160,6 +177,7 @@ static struct intel_sst_ops mrfld_ops = {
 	.reset = intel_sst_reset_dsp_mrfld,
 	.post_message = sst_post_message_mrfld,
 	.process_reply = sst_process_reply_mrfld,
+	.save_dsp_context =  sst_save_dsp_context_v2,
 	.alloc_stream = sst_alloc_stream_mrfld,
 	.post_download = sst_post_download_mrfld,
 };
@@ -418,6 +436,50 @@ static void intel_sst_remove(struct pci_dev *pci)
 	pci_set_drvdata(pci, NULL);
 }
 
+static int intel_sst_runtime_suspend(struct device *dev)
+{
+	int ret = 0;
+	struct intel_sst_drv *ctx = dev_get_drvdata(dev);
+
+	if (ctx->sst_state == SST_RESET) {
+		dev_dbg(dev, "LPE is already in RESET state, No action\n");
+		return 0;
+	}
+	/* save fw context */
+	if (ctx->ops->save_dsp_context(ctx))
+		return -EBUSY;
+
+	/* Move the SST state to Reset */
+	sst_set_fw_state_locked(ctx, SST_RESET);
+
+	synchronize_irq(ctx->irq_num);
+	flush_workqueue(ctx->post_msg_wq);
+
+	return ret;
+}
+
+static int intel_sst_runtime_resume(struct device *dev)
+{
+	int ret = 0;
+	struct intel_sst_drv *ctx = dev_get_drvdata(dev);
+
+	mutex_lock(&ctx->sst_lock);
+	if (ctx->sst_state == SST_RESET) {
+		ret = sst_load_fw(ctx);
+		if (ret) {
+			dev_err(dev, "FW download fail %d\n", ret);
+			ctx->sst_state = SST_RESET;
+		}
+	}
+	mutex_unlock(&ctx->sst_lock);
+	return ret;
+}
+
+static const struct dev_pm_ops intel_sst_pm = {
+	.runtime_suspend = intel_sst_runtime_suspend,
+	.runtime_resume = intel_sst_runtime_resume,
+};
+
 /* PCI Routines */
 static struct pci_device_id intel_sst_ids[] = {
 	{ PCI_VDEVICE(INTEL, SST_MRFLD_PCI_ID), 0},
@@ -429,6 +491,11 @@ static struct pci_driver sst_driver = {
 	.id_table = intel_sst_ids,
 	.probe = intel_sst_probe,
 	.remove = intel_sst_remove,
+#ifdef CONFIG_PM
+	.driver = {
+		.pm = &intel_sst_pm,
+	},
+#endif
 };
 
 module_pci_driver(sst_driver);