Patch "leds / PM: fix hibernation on arm when gpio-led used with CPU led trigger" has been added to the 4.0-stable tree

This is a note to let you know that I've just added the patch titled

leds / PM: fix hibernation on arm when gpio-led used with CPU led trigger

to the 4.0-stable tree which can be found at:
http://www.kernel.org/git/?p=linux/kernel/git/stable/stable-queue.git;a=summary

The filename of the patch is:
leds-pm-fix-hibernation-on-arm-when-gpio-led-used-with-cpu-led-trigger.patch
and it can be found in the queue-4.0 subdirectory.

If you, or anyone else, feels it should not be added to the stable tree, please let <[email protected]> know about it.

From: Grygorii Strashko <[email protected]>
Date: Fri, 24 Apr 2015 14:57:10 +0300
Subject: leds / PM: fix hibernation on arm when gpio-led used with CPU led trigger

From: Grygorii Strashko <[email protected]>

commit 084609bf727981c7a2e6e69aefe0052c9d793300 upstream.

Setting a dev_pm_ops suspend/resume pair of callbacks but not a set of hibernation callbacks means those pm functions will not be called upon hibernation - that leads to system crash on ARM during freezing if gpio-led is used in combination with CPU led trigger. It may happen after freeze_noirq stage (GPIO is suspended) and before syscore_suspend stage (CPU led trigger is suspended)
- usually when disable_nonboot_cpus() is called.

Log:
PM: noirq freeze of devices complete after 1.425 msecs Disabling non-boot CPUs ...
^ system may crash or stuck here with message (TI AM572x)

  WARNING: CPU: 0 PID: 3100 at drivers/bus/omap_l3_noc.c:148 l3_interrupt_handler+0x22c/0x370()
  44000000.ocp:L3 Custom Error: MASTER MPU TARGET L4_PER1_P3 (Idle): Data Access in Supervisor mode during Functional access

CPU1: shutdown
^ or here

Fix this by using SIMPLE_DEV_PM_OPS, which appropriately assigns the suspend and hibernation callbacks and move led_suspend/led_resume under CONFIG_PM_SLEEP to avoid build warnings.

---
 drivers/leds/led-class.c |    7 +++----
 1 file changed, 3 insertions(+), 4 deletions(-)

@@ -187,6 +187,7 @@ void led_classdev_resume(struct led_clas
 }
 EXPORT_SYMBOL_GPL(led_classdev_resume);
 
+#ifdef CONFIG_PM_SLEEP
 static int led_suspend(struct device *dev)
 {
 	struct led_classdev *led_cdev = dev_get_drvdata(dev);

@@ -206,11 +207,9 @@ static int led_resume(struct device *dev
 
 	return 0;
 }
+#endif
 
-static const struct dev_pm_ops leds_class_dev_pm_ops = {
-	.suspend        = led_suspend,
-	.resume         = led_resume,
-};
+static SIMPLE_DEV_PM_OPS(leds_class_dev_pm_ops, led_suspend, led_resume);
 
 /**
  * led_classdev_register - register a new object of led_classdev class.

Patches currently in stable-queue which might be from [email protected] are

queue-4.0/leds-pm-fix-hibernation-on-arm-when-gpio-led-used-with-cpu-led-trigger.patch