1 files changed, 22 insertions, 4 deletions

diff --git a/drivers/leds/led-class.c b/drivers/leds/led-class.c
index 06b97fd49ad9..2a04ac61574d 100644
--- a/drivers/leds/led-class.c
+++ b/drivers/leds/led-class.c
@@ -25,15 +25,20 @@
 static DEFINE_MUTEX(leds_lookup_lock);
 static LIST_HEAD(leds_lookup_list);
 
+static struct workqueue_struct *leds_wq;
+
 static ssize_t brightness_show(struct device *dev,
 		struct device_attribute *attr, char *buf)
 {
 	struct led_classdev *led_cdev = dev_get_drvdata(dev);
+	unsigned int brightness;
 
-	/* no lock needed for this */
+	mutex_lock(&led_cdev->led_access);
 	led_update_brightness(led_cdev);
+	brightness = led_cdev->brightness;
+	mutex_unlock(&led_cdev->led_access);
 
-	return sprintf(buf, "%u\n", led_cdev->brightness);
+	return sprintf(buf, "%u\n", brightness);
 }
 
 static ssize_t brightness_store(struct device *dev,
@@ -57,7 +62,6 @@ static ssize_t brightness_store(struct device *dev,
 	if (state == LED_OFF)
 		led_trigger_remove(led_cdev);
 	led_set_brightness(led_cdev, state);
-	flush_work(&led_cdev->set_brightness_work);
 
 	ret = size;
 unlock:
@@ -70,8 +74,13 @@ static ssize_t max_brightness_show(struct device *dev,
 		struct device_attribute *attr, char *buf)
 {
 	struct led_classdev *led_cdev = dev_get_drvdata(dev);
+	unsigned int max_brightness;
 
-	return sprintf(buf, "%u\n", led_cdev->max_brightness);
+	mutex_lock(&led_cdev->led_access);
+	max_brightness = led_cdev->max_brightness;
+	mutex_unlock(&led_cdev->led_access);
+
+	return sprintf(buf, "%u\n", max_brightness);
 }
 static DEVICE_ATTR_RO(max_brightness);
 
@@ -549,6 +558,8 @@ int led_classdev_register_ext(struct device *parent,
 
 	led_update_brightness(led_cdev);
 
+	led_cdev->wq = leds_wq;
+
 	led_init_core(led_cdev);
 
 #ifdef CONFIG_LEDS_TRIGGERS
@@ -667,12 +678,19 @@ EXPORT_SYMBOL_GPL(devm_led_classdev_unregister);
 
 static int __init leds_init(void)
 {
+	leds_wq = alloc_ordered_workqueue("leds", 0);
+	if (!leds_wq) {
+		pr_err("Failed to create LEDs ordered workqueue\n");
+		return -ENOMEM;
+	}
+
 	return class_register(&leds_class);
 }
 
 static void __exit leds_exit(void)
 {
 	class_unregister(&leds_class);
+	destroy_workqueue(leds_wq);
 }
 
 subsys_initcall(leds_init);