Commit a8636c89 authored Oct 17, 2016 by Ulf Hansson Committed by Rafael J. Wysocki Nov 09, 2016

PM / Runtime: Don't allow to suspend a device with an active child



When resuming a device in __pm_runtime_set_status(), the prerequisite is
that its parent must already be active, else an error code is returned and
the device's status remains suspended.

When suspending a device there is no similar constraints being validated.
Let's change this to make the behaviour consistent, by not allowing to
suspend a device with an active child, unless it has been explicitly set to
ignore its children.

Signed-off-by: Ulf Hansson <ulf.hansson@linaro.org>
Reviewed-by: Linus Walleij <linus.walleij@linaro.org>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>

parent 88128729

drivers/base/power/runtime.c

+11 −1

Original line number	Diff line number	Diff line
		@@ -1028,7 +1028,17 @@ int __pm_runtime_set_status(struct device *dev, unsigned int status)
		goto out_set;

		if (status == RPM_SUSPENDED) {
		/* It always is possible to set the status to 'suspended'. */
		/*
		* It is invalid to suspend a device with an active child,
		* unless it has been set to ignore its children.
		*/
		if (!dev->power.ignore_children &&
		atomic_read(&dev->power.child_count)) {
		dev_err(dev, "runtime PM trying to suspend device but active child\n");
		error = -EBUSY;
		goto out;
		}

		if (parent) {
		atomic_add_unless(&parent->power.child_count, -1, 0);
		notify_parent = !parent->power.ignore_children;