Merge tag 'pm-4.17-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/rafael/linux-pm

Pull power management updates from Rafael Wysocki:
 "These update the cpuidle poll state definition to reduce excessive
  energy usage related to it, add new CPU ID to the RAPL power capping
  driver, update the ACPI system suspend code to handle some special
  cases better, extend the PM core's device links code slightly, add new
  sysfs attribute for better suspend-to-idle diagnostics and easier
  hibernation handling, update power management tools and clean up
  cpufreq quite a bit.

  Specifics:

   - Modify the cpuidle poll state implementation to prevent CPUs from
     staying in the loop in there for excessive times (Rafael Wysocki).

   - Add Intel Cannon Lake chips support to the RAPL power capping
     driver (Joe Konno).

   - Add reference counting to the device links handling code in the PM
     core (Lukas Wunner).

   - Avoid reconfiguring GPEs on suspend-to-idle in the ACPI system
     suspend code (Rafael Wysocki).

   - Allow devices to be put into deeper low-power states via ACPI if
     both _SxD and _SxW are missing (Daniel Drake).

   - Reorganize the core ACPI suspend-to-idle wakeup code to avoid a
     keyboard wakeup issue on Asus UX331UA (Chris Chiu).

   - Prevent the PCMCIA library code from aborting suspend-to-idle due
     to noirq suspend failures resulting from incorrect assumptions
     (Rafael Wysocki).

   - Add coupled cpuidle supprt to the Exynos3250 platform (Marek
     Szyprowski).

   - Add new sysfs file to make it easier to specify the image storage
     location during hibernation (Mario Limonciello).

   - Add sysfs files for collecting suspend-to-idle usage and time
     statistics for CPU idle states (Rafael Wysocki).

   - Update the pm-graph utilities (Todd Brandt).

   - Reduce the kernel log noise related to reporting Low-power Idle
     constraings by the ACPI system suspend code (Rafael Wysocki).

   - Make it easier to distinguish dedicated wakeup IRQs in the
     /proc/interrupts output (Tony Lindgren).

   - Add the frequency table validation in cpufreq to the core and drop
     it from a number of cpufreq drivers (Viresh Kumar).

   - Drop "cooling-{min|max}-level" for CPU nodes from a couple of DT
     bindings (Viresh Kumar).

   - Clean up the CPU online error code path in the cpufreq core (Viresh
     Kumar).

   - Fix assorted issues in the SCPI, CPPC, mediatek and tegra186
     cpufreq drivers (Arnd Bergmann, Chunyu Hu, George Cherian, Viresh
     Kumar).

   - Drop memory allocation error messages from a few places in cpufreq
     and cpuildle drivers (Markus Elfring)"

* tag 'pm-4.17-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/rafael/linux-pm: (56 commits)
  ACPI / PM: Fix keyboard wakeup from suspend-to-idle on ASUS UX331UA
  cpufreq: CPPC: Use transition_delay_us depending transition_latency
  PM / hibernate: Change message when writing to /sys/power/resume
  PM / hibernate: Make passing hibernate offsets more friendly
  cpuidle: poll_state: Avoid invoking local_clock() too often
  PM: cpuidle/suspend: Add s2idle usage and time state attributes
  cpuidle: Enable coupled cpuidle support on Exynos3250 platform
  cpuidle: poll_state: Add time limit to poll_idle()
  cpufreq: tegra186: Don't validate the frequency table twice
  cpufreq: speedstep: Don't validate the frequency table twice
  cpufreq: sparc: Don't validate the frequency table twice
  cpufreq: sh: Don't validate the frequency table twice
  cpufreq: sfi: Don't validate the frequency table twice
  cpufreq: scpi: Don't validate the frequency table twice
  cpufreq: sc520: Don't validate the frequency table twice
  cpufreq: s3c24xx: Don't validate the frequency table twice
  cpufreq: qoirq: Don't validate the frequency table twice
  cpufreq: pxa: Don't validate the frequency table twice
  cpufreq: ppc_cbe: Don't validate the frequency table twice
  cpufreq: powernow: Don't validate the frequency table twice
  ...

3 files changed, 29 insertions, 10 deletions

diff --git a/drivers/base/core.c b/drivers/base/core.c
index 5847364f25d9..b610816eb887 100644
--- a/drivers/base/core.c
+++ b/drivers/base/core.c
@@ -196,8 +196,10 @@ struct device_link *device_link_add(struct device *consumer,
 	}
 
 	list_for_each_entry(link, &supplier->links.consumers, s_node)
-		if (link->consumer == consumer)
+		if (link->consumer == consumer) {
+			kref_get(&link->kref);
 			goto out;
+		}
 
 	link = kzalloc(sizeof(*link), GFP_KERNEL);
 	if (!link)
@@ -222,6 +224,7 @@ struct device_link *device_link_add(struct device *consumer,
 	link->consumer = consumer;
 	INIT_LIST_HEAD(&link->c_node);
 	link->flags = flags;
+	kref_init(&link->kref);
 
 	/* Determine the initial link state. */
 	if (flags & DL_FLAG_STATELESS) {
@@ -292,8 +295,10 @@ static void __device_link_free_srcu(struct rcu_head *rhead)
 	device_link_free(container_of(rhead, struct device_link, rcu_head));
 }
 
-static void __device_link_del(struct device_link *link)
+static void __device_link_del(struct kref *kref)
 {
+	struct device_link *link = container_of(kref, struct device_link, kref);
+
 	dev_info(link->consumer, "Dropping the link to %s\n",
 		 dev_name(link->supplier));
 
@@ -305,8 +310,10 @@ static void __device_link_del(struct device_link *link)
 	call_srcu(&device_links_srcu, &link->rcu_head, __device_link_free_srcu);
 }
 #else /* !CONFIG_SRCU */
-static void __device_link_del(struct device_link *link)
+static void __device_link_del(struct kref *kref)
 {
+	struct device_link *link = container_of(kref, struct device_link, kref);
+
 	dev_info(link->consumer, "Dropping the link to %s\n",
 		 dev_name(link->supplier));
 
@@ -324,13 +331,15 @@ static void __device_link_del(struct device_link *link)
  * @link: Device link to delete.
  *
  * The caller must ensure proper synchronization of this function with runtime
- * PM.
+ * PM.  If the link was added multiple times, it needs to be deleted as often.
+ * Care is required for hotplugged devices:  Their links are purged on removal
+ * and calling device_link_del() is then no longer allowed.
  */
 void device_link_del(struct device_link *link)
 {
 	device_links_write_lock();
 	device_pm_lock();
-	__device_link_del(link);
+	kref_put(&link->kref, __device_link_del);
 	device_pm_unlock();
 	device_links_write_unlock();
 }
@@ -444,7 +453,7 @@ static void __device_links_no_driver(struct device *dev)
 			continue;
 
 		if (link->flags & DL_FLAG_AUTOREMOVE)
-			__device_link_del(link);
+			kref_put(&link->kref, __device_link_del);
 		else if (link->status != DL_STATE_SUPPLIER_UNBIND)
 			WRITE_ONCE(link->status, DL_STATE_AVAILABLE);
 	}
@@ -597,13 +606,13 @@ static void device_links_purge(struct device *dev)
 
 	list_for_each_entry_safe_reverse(link, ln, &dev->links.suppliers, c_node) {
 		WARN_ON(link->status == DL_STATE_ACTIVE);
-		__device_link_del(link);
+		__device_link_del(&link->kref);
 	}
 
 	list_for_each_entry_safe_reverse(link, ln, &dev->links.consumers, s_node) {
 		WARN_ON(link->status != DL_STATE_DORMANT &&
 			link->status != DL_STATE_NONE);
-		__device_link_del(link);
+		__device_link_del(&link->kref);
 	}
 
 	device_links_write_unlock();
diff --git a/drivers/base/power/power.h b/drivers/base/power/power.h
index 21244c53e377..86e67e70b509 100644
--- a/drivers/base/power/power.h
+++ b/drivers/base/power/power.h
@@ -31,6 +31,7 @@ struct wake_irq {
 	struct device *dev;
 	unsigned int status;
 	int irq;
+	const char *name;
 };
 
 extern void dev_pm_arm_wake_irq(struct wake_irq *wirq);
diff --git a/drivers/base/power/wakeirq.c b/drivers/base/power/wakeirq.c
index 6637fc319269..b8fa5c0f2d13 100644
--- a/drivers/base/power/wakeirq.c
+++ b/drivers/base/power/wakeirq.c
@@ -112,6 +112,7 @@ void dev_pm_clear_wake_irq(struct device *dev)
 		free_irq(wirq->irq, wirq);
 		wirq->status &= ~WAKE_IRQ_DEDICATED_MASK;
 	}
+	kfree(wirq->name);
 	kfree(wirq);
 }
 EXPORT_SYMBOL_GPL(dev_pm_clear_wake_irq);
@@ -184,6 +185,12 @@ int dev_pm_set_dedicated_wake_irq(struct device *dev, int irq)
 	if (!wirq)
 		return -ENOMEM;
 
+	wirq->name = kasprintf(GFP_KERNEL, "%s:wakeup", dev_name(dev));
+	if (!wirq->name) {
+		err = -ENOMEM;
+		goto err_free;
+	}
+
 	wirq->dev = dev;
 	wirq->irq = irq;
 	irq_set_status_flags(irq, IRQ_NOAUTOEN);
@@ -196,9 +203,9 @@ int dev_pm_set_dedicated_wake_irq(struct device *dev, int irq)
 	 * so we use a threaded irq.
 	 */
 	err = request_threaded_irq(irq, NULL, handle_threaded_wake_irq,
-				   IRQF_ONESHOT, dev_name(dev), wirq);
+				   IRQF_ONESHOT, wirq->name, wirq);
 	if (err)
-		goto err_free;
+		goto err_free_name;
 
 	err = dev_pm_attach_wake_irq(dev, irq, wirq);
 	if (err)
@@ -210,6 +217,8 @@ int dev_pm_set_dedicated_wake_irq(struct device *dev, int irq)
 
 err_free_irq:
 	free_irq(irq, wirq);
+err_free_name:
+	kfree(wirq->name);
 err_free:
 	kfree(wirq);