1 files changed, 44 insertions, 6 deletions

diff --git a/drivers/base/power/runtime.c b/drivers/base/power/runtime.c
index e1a10a03df8e..4c7055009bd6 100644
--- a/drivers/base/power/runtime.c
+++ b/drivers/base/power/runtime.c
@@ -966,6 +966,30 @@ int __pm_runtime_resume(struct device *dev, int rpmflags)
 EXPORT_SYMBOL_GPL(__pm_runtime_resume);
 
 /**
+ * pm_runtime_get_if_in_use - Conditionally bump up the device's usage counter.
+ * @dev: Device to handle.
+ *
+ * Return -EINVAL if runtime PM is disabled for the device.
+ *
+ * If that's not the case and if the device's runtime PM status is RPM_ACTIVE
+ * and the runtime PM usage counter is nonzero, increment the counter and
+ * return 1.  Otherwise return 0 without changing the counter.
+ */
+int pm_runtime_get_if_in_use(struct device *dev)
+{
+	unsigned long flags;
+	int retval;
+
+	spin_lock_irqsave(&dev->power.lock, flags);
+	retval = dev->power.disable_depth > 0 ? -EINVAL :
+		dev->power.runtime_status == RPM_ACTIVE
+			&& atomic_inc_not_zero(&dev->power.usage_count);
+	spin_unlock_irqrestore(&dev->power.lock, flags);
+	return retval;
+}
+EXPORT_SYMBOL_GPL(pm_runtime_get_if_in_use);
+
+/**
  * __pm_runtime_set_status - Set runtime PM status of a device.
  * @dev: Device to handle.
  * @status: New runtime PM status of the device.
@@ -1390,18 +1414,32 @@ void pm_runtime_init(struct device *dev)
 }
 
 /**
+ * pm_runtime_reinit - Re-initialize runtime PM fields in given device object.
+ * @dev: Device object to re-initialize.
+ */
+void pm_runtime_reinit(struct device *dev)
+{
+	if (!pm_runtime_enabled(dev)) {
+		if (dev->power.runtime_status == RPM_ACTIVE)
+			pm_runtime_set_suspended(dev);
+		if (dev->power.irq_safe) {
+			spin_lock_irq(&dev->power.lock);
+			dev->power.irq_safe = 0;
+			spin_unlock_irq(&dev->power.lock);
+			if (dev->parent)
+				pm_runtime_put(dev->parent);
+		}
+	}
+}
+
+/**
  * pm_runtime_remove - Prepare for removing a device from device hierarchy.
  * @dev: Device object being removed from device hierarchy.
  */
 void pm_runtime_remove(struct device *dev)
 {
 	__pm_runtime_disable(dev, false);
-
-	/* Change the status back to 'suspended' to match the initial status. */
-	if (dev->power.runtime_status == RPM_ACTIVE)
-		pm_runtime_set_suspended(dev);
-	if (dev->power.irq_safe && dev->parent)
-		pm_runtime_put(dev->parent);
+	pm_runtime_reinit(dev);
 }
 
 /**