Merge tag 'pm-5.12-rc5' of git://git.kernel.org/pub/scm/linux/kernel/git/rafael/linux-pm

Pull power management fixes from Rafael Wysocki:
 "These fix an issue related to device links in the runtime PM framework
  and debugfs usage in the Energy Model code.

  Specifics:

   - Modify the runtime PM device suspend to avoid suspending supplier
     devices before the consumer device's status changes to
     RPM_SUSPENDED (Rafael Wysocki)

   - Change the Energy Model code to prevent it from attempting to
     create its main debugfs directory too early (Lukasz Luba)"

* tag 'pm-5.12-rc5' of git://git.kernel.org/pub/scm/linux/kernel/git/rafael/linux-pm:
  PM: EM: postpone creating the debugfs dir till fs_initcall
  PM: runtime: Defer suspending suppliers

Author: torvalds

drivers/base/power/runtime.c

@@ -305,18 +305,38 @@ static int rpm_get_suppliers(struct device *dev)
 	return 0;
 }
 
-static void rpm_put_suppliers(struct device *dev)
+static void __rpm_put_suppliers(struct device *dev, bool try_to_suspend)
 {
 	struct device_link *link;
 
 	list_for_each_entry_rcu(link, &dev->links.suppliers, c_node,
 				device_links_read_lock_held()) {
 
 		while (refcount_dec_not_one(&link->rpm_active))
-			pm_runtime_put(link->supplier);
+			pm_runtime_put_noidle(link->supplier);
+
+		if (try_to_suspend)
+			pm_request_idle(link->supplier);
 	}
 }
 
+static void rpm_put_suppliers(struct device *dev)
+{
+	__rpm_put_suppliers(dev, true);
+}
+
+static void rpm_suspend_suppliers(struct device *dev)
+{
+	struct device_link *link;
+	int idx = device_links_read_lock();
+
+	list_for_each_entry_rcu(link, &dev->links.suppliers, c_node,
+				device_links_read_lock_held())
+		pm_request_idle(link->supplier);
+
+	device_links_read_unlock(idx);
+}
+
 /**
  * __rpm_callback - Run a given runtime PM callback for a given device.
  * @cb: Runtime PM callback to run.
@@ -344,8 +364,10 @@ static int __rpm_callback(int (*cb)(struct device *), struct device *dev)
 			idx = device_links_read_lock();
 
 			retval = rpm_get_suppliers(dev);
-			if (retval)
+			if (retval) {
+				rpm_put_suppliers(dev);
 				goto fail;
+			}
 
 			device_links_read_unlock(idx);
 		}
@@ -368,9 +390,9 @@ static int __rpm_callback(int (*cb)(struct device *), struct device *dev)
 		    || (dev->power.runtime_status == RPM_RESUMING && retval))) {
 			idx = device_links_read_lock();
 
- fail:
-			rpm_put_suppliers(dev);
+			__rpm_put_suppliers(dev, false);
 
+fail:
 			device_links_read_unlock(idx);
 		}
 
@@ -642,8 +664,11 @@ static int rpm_suspend(struct device *dev, int rpmflags)
 		goto out;
 	}
 
+	if (dev->power.irq_safe)
+		goto out;
+
 	/* Maybe the parent is now able to suspend. */
-	if (parent && !parent->power.ignore_children && !dev->power.irq_safe) {
+	if (parent && !parent->power.ignore_children) {
 		spin_unlock(&dev->power.lock);
 
 		spin_lock(&parent->power.lock);
@@ -652,6 +677,14 @@ static int rpm_suspend(struct device *dev, int rpmflags)
 
 		spin_lock(&dev->power.lock);
 	}
+	/* Maybe the suppliers are now able to suspend. */
+	if (dev->power.links_count > 0) {
+		spin_unlock_irq(&dev->power.lock);
+
+		rpm_suspend_suppliers(dev);
+
+		spin_lock_irq(&dev->power.lock);
+	}
 
  out:
 	trace_rpm_return_int_rcuidle(dev, _THIS_IP_, retval);

kernel/power/energy_model.c

@@ -98,7 +98,7 @@ static int __init em_debug_init(void)
 
 	return 0;
 }
-core_initcall(em_debug_init);
+fs_initcall(em_debug_init);
 #else /* CONFIG_DEBUG_FS */
 static void em_debug_create_pd(struct device *dev) {}
 static void em_debug_remove_pd(struct device *dev) {}