[PATCH 17/19] soundwire: amd: add pm_prepare callback and pm ops support

[Vijendar Mukunda <Vijendar.Mukunda@amd.com>]

Add pm_prepare callback and System level pm ops support for
AMD master driver.

Signed-off-by: Vijendar Mukunda <Vijendar.Mukunda@amd.com>
Signed-off-by: Mastan Katragadda <Mastan.Katragadda@amd.com>
---
 drivers/soundwire/amd_master.c | 76 ++++++++++++++++++++++++++++++++++
 1 file changed, 76 insertions(+)

diff --git a/drivers/soundwire/amd_master.c b/drivers/soundwire/amd_master.c
index 2fd77a673c22..f4478cc17aac 100644
--- a/drivers/soundwire/amd_master.c
+++ b/drivers/soundwire/amd_master.c
@@ -1552,6 +1552,80 @@ static int amd_sdwc_clock_stop_exit(struct amd_sdwc_ctrl *ctrl)
 	return 0;
 }
 
+static int amd_resume_child_device(struct device *dev, void *data)
+{
+	int ret;
+	struct sdw_slave *slave = dev_to_sdw_dev(dev);
+
+	if (!slave->probed) {
+		dev_dbg(dev, "skipping device, no probed driver\n");
+		return 0;
+	}
+	if (!slave->dev_num_sticky) {
+		dev_dbg(dev, "skipping device, never detected on bus\n");
+		return 0;
+	}
+
+	if (!pm_runtime_suspended(dev))
+		return 0;
+	ret = pm_request_resume(dev);
+	if (ret < 0)
+		dev_err(dev, "%s: pm_request_resume failed: %d\n", __func__, ret);
+
+	return ret;
+}
+
+static int __maybe_unused amd_pm_prepare(struct device *dev)
+{
+	struct amd_sdwc_ctrl *ctrl = dev_get_drvdata(dev);
+	struct sdw_bus *bus = &ctrl->bus;
+	int ret;
+
+	if (bus->prop.hw_disabled || !ctrl->startup_done) {
+		dev_dbg(bus->dev, "SoundWire master %d is disabled or not-started, ignoring\n",
+			bus->link_id);
+		return 0;
+	}
+	ret = device_for_each_child(bus->dev, NULL, amd_resume_child_device);
+	if (ret < 0)
+		dev_err(dev, "%s: amd_resume_child_device failed: %d\n", __func__, ret);
+	if (pm_runtime_suspended(dev) && ctrl->power_mode_mask & AMD_SDW_CLK_STOP_MODE) {
+		ret = pm_request_resume(dev);
+		if (ret < 0) {
+			dev_err(bus->dev, "pm_request_resume failed: %d\n", ret);
+			return 0;
+		}
+	}
+	return 0;
+}
+
+static int __maybe_unused amd_suspend(struct device *dev)
+{
+	struct amd_sdwc_ctrl *ctrl = dev_get_drvdata(dev);
+	struct sdw_bus *bus = &ctrl->bus;
+	int ret;
+
+	if (bus->prop.hw_disabled || !ctrl->startup_done) {
+		dev_dbg(bus->dev, "SoundWire master %d is disabled or not-started, ignoring\n",
+			bus->link_id);
+		return 0;
+	}
+
+	if (ctrl->power_mode_mask & AMD_SDW_CLK_STOP_MODE) {
+		ret = amd_sdwc_clock_stop(ctrl);
+		if (ret)
+			return ret;
+	} else if (ctrl->power_mode_mask & AMD_SDW_POWER_OFF_MODE) {
+		ret = amd_sdwc_clock_stop(ctrl);
+		if (ret)
+			return ret;
+		ret = amd_deinit_sdw_controller(ctrl);
+		if (ret)
+			return ret;
+	}
+	return 0;
+}
+
 static int __maybe_unused amd_suspend_runtime(struct device *dev)
 {
 	struct amd_sdwc_ctrl *ctrl = dev_get_drvdata(dev);
@@ -1638,6 +1712,8 @@ static int __maybe_unused amd_resume_runtime(struct device *dev)
 }
 
 static const struct dev_pm_ops amd_pm = {
+	.prepare = amd_pm_prepare,
+	SET_SYSTEM_SLEEP_PM_OPS(amd_suspend, amd_resume_runtime)
 	SET_RUNTIME_PM_OPS(amd_suspend_runtime, amd_resume_runtime, NULL)
 };
 
-- 
2.34.1