1 files changed, 30 insertions, 3 deletions

diff --git a/drivers/tty/serdev/core.c b/drivers/tty/serdev/core.c
index 9e59f4788589..bd47c46ec993 100644
--- a/drivers/tty/serdev/core.c
+++ b/drivers/tty/serdev/core.c
@@ -13,6 +13,7 @@
 #include <linux/module.h>
 #include <linux/of.h>
 #include <linux/of_device.h>
+#include <linux/pm_runtime.h>
 #include <linux/serdev.h>
 #include <linux/slab.h>
 
@@ -143,11 +144,28 @@ EXPORT_SYMBOL_GPL(serdev_device_remove);
 int serdev_device_open(struct serdev_device *serdev)
 {
 	struct serdev_controller *ctrl = serdev->ctrl;
+	int ret;
 
 	if (!ctrl || !ctrl->ops->open)
 		return -EINVAL;
 
-	return ctrl->ops->open(ctrl);
+	ret = ctrl->ops->open(ctrl);
+	if (ret)
+		return ret;
+
+	ret = pm_runtime_get_sync(&ctrl->dev);
+	if (ret < 0) {
+		pm_runtime_put_noidle(&ctrl->dev);
+		goto err_close;
+	}
+
+	return 0;
+
+err_close:
+	if (ctrl->ops->close)
+		ctrl->ops->close(ctrl);
+
+	return ret;
 }
 EXPORT_SYMBOL_GPL(serdev_device_open);
 
@@ -158,6 +176,8 @@ void serdev_device_close(struct serdev_device *serdev)
 	if (!ctrl || !ctrl->ops->close)
 		return;
 
+	pm_runtime_put(&ctrl->dev);
+
 	ctrl->ops->close(ctrl);
 }
 EXPORT_SYMBOL_GPL(serdev_device_close);
@@ -416,6 +436,9 @@ struct serdev_controller *serdev_controller_alloc(struct device *parent,
 
 	dev_set_name(&ctrl->dev, "serial%d", id);
 
+	pm_runtime_no_callbacks(&ctrl->dev);
+	pm_suspend_ignore_children(&ctrl->dev, true);
+
 	dev_dbg(&ctrl->dev, "allocated controller 0x%p id %d\n", ctrl, id);
 	return ctrl;
 
@@ -547,20 +570,23 @@ int serdev_controller_add(struct serdev_controller *ctrl)
 	if (ret)
 		return ret;
 
+	pm_runtime_enable(&ctrl->dev);
+
 	ret_of = of_serdev_register_devices(ctrl);
 	ret_acpi = acpi_serdev_register_devices(ctrl);
 	if (ret_of && ret_acpi) {
 		dev_dbg(&ctrl->dev, "no devices registered: of:%d acpi:%d\n",
 			ret_of, ret_acpi);
 		ret = -ENODEV;
-		goto out_dev_del;
+		goto err_rpm_disable;
 	}
 
 	dev_dbg(&ctrl->dev, "serdev%d registered: dev:%p\n",
 		ctrl->nr, &ctrl->dev);
 	return 0;
 
-out_dev_del:
+err_rpm_disable:
+	pm_runtime_disable(&ctrl->dev);
 	device_del(&ctrl->dev);
 	return ret;
 };
@@ -591,6 +617,7 @@ void serdev_controller_remove(struct serdev_controller *ctrl)
 
 	dummy = device_for_each_child(&ctrl->dev, NULL,
 				      serdev_remove_device);
+	pm_runtime_disable(&ctrl->dev);
 	device_del(&ctrl->dev);
 }
 EXPORT_SYMBOL_GPL(serdev_controller_remove);