7 files changed, 53 insertions, 29 deletions

diff --git a/drivers/leds/led-class.c b/drivers/leds/led-class.c
index aa29198fca3e..7440c58b8e6f 100644
--- a/drivers/leds/led-class.c
+++ b/drivers/leds/led-class.c
@@ -9,26 +9,21 @@
  * published by the Free Software Foundation.
  */
 
-#include <linux/module.h>
-#include <linux/kernel.h>
+#include <linux/ctype.h>
+#include <linux/device.h>
+#include <linux/err.h>
 #include <linux/init.h>
+#include <linux/kernel.h>
+#include <linux/leds.h>
 #include <linux/list.h>
+#include <linux/module.h>
+#include <linux/slab.h>
 #include <linux/spinlock.h>
-#include <linux/device.h>
 #include <linux/timer.h>
-#include <linux/err.h>
-#include <linux/ctype.h>
-#include <linux/leds.h>
 #include "leds.h"
 
 static struct class *leds_class;
 
-static void led_update_brightness(struct led_classdev *led_cdev)
-{
-        if (led_cdev->brightness_get)
-                led_cdev->brightness = led_cdev->brightness_get(led_cdev);
-}
-
 static ssize_t brightness_show(struct device *dev,
                 struct device_attribute *attr, char *buf)
 {
@@ -59,14 +54,14 @@ static ssize_t brightness_store(struct device *dev,
 }
 static DEVICE_ATTR_RW(brightness);
 
-static ssize_t led_max_brightness_show(struct device *dev,
+static ssize_t max_brightness_show(struct device *dev,
                 struct device_attribute *attr, char *buf)
 {
         struct led_classdev *led_cdev = dev_get_drvdata(dev);
 
         return sprintf(buf, "%u\n", led_cdev->max_brightness);
 }
-static DEVICE_ATTR(max_brightness, 0444, led_max_brightness_show, NULL);
+static DEVICE_ATTR_RO(max_brightness);
 
 #ifdef CONFIG_LEDS_TRIGGERS
 static DEVICE_ATTR(trigger, 0644, led_trigger_show, led_trigger_store);
diff --git a/drivers/leds/led-core.c b/drivers/leds/led-core.c
index 71b40d3bf776..aaa8eba9099f 100644
--- a/drivers/leds/led-core.c
+++ b/drivers/leds/led-core.c
@@ -12,10 +12,11 @@
  */
 
 #include <linux/kernel.h>
+#include <linux/leds.h>
 #include <linux/list.h>
 #include <linux/module.h>
+#include <linux/mutex.h>
 #include <linux/rwsem.h>
-#include <linux/leds.h>
 #include "leds.h"
 
 DECLARE_RWSEM(leds_list_lock);
@@ -126,3 +127,19 @@ void led_set_brightness(struct led_classdev *led_cdev,
         __led_set_brightness(led_cdev, brightness);
 }
 EXPORT_SYMBOL(led_set_brightness);
+
+int led_update_brightness(struct led_classdev *led_cdev)
+{
+        int ret = 0;
+
+        if (led_cdev->brightness_get) {
+                ret = led_cdev->brightness_get(led_cdev);
+                if (ret >= 0) {
+                        led_cdev->brightness = ret;
+                        return 0;
+                }
+        }
+
+        return ret;
+}
+EXPORT_SYMBOL(led_update_brightness);
diff --git a/drivers/leds/leds-gpio-register.c b/drivers/leds/leds-gpio-register.c
index 1c4ed5510f35..75717ba68ae0 100644
--- a/drivers/leds/leds-gpio-register.c
+++ b/drivers/leds/leds-gpio-register.c
@@ -7,9 +7,9 @@
  * Free Software Foundation.
  */
 #include <linux/err.h>
+#include <linux/leds.h>
 #include <linux/platform_device.h>
 #include <linux/slab.h>
-#include <linux/leds.h>
 
 /**
  * gpio_led_register_device - register a gpio-led device
@@ -28,6 +28,9 @@ struct platform_device *__init gpio_led_register_device(
         struct platform_device *ret;
         struct gpio_led_platform_data _pdata = *pdata;
 
+        if (!pdata->num_leds)
+                return ERR_PTR(-EINVAL);
+
         _pdata.leds = kmemdup(pdata->leds,
                         pdata->num_leds * sizeof(*pdata->leds), GFP_KERNEL);
         if (!_pdata.leds)
diff --git a/drivers/leds/leds-gpio.c b/drivers/leds/leds-gpio.c
index 57ff20fecf57..b4518c8751c8 100644
--- a/drivers/leds/leds-gpio.c
+++ b/drivers/leds/leds-gpio.c
@@ -10,17 +10,17 @@
  * published by the Free Software Foundation.
  *
  */
-#include <linux/kernel.h>
-#include <linux/platform_device.h>
+#include <linux/err.h>
 #include <linux/gpio.h>
+#include <linux/kernel.h>
 #include <linux/leds.h>
+#include <linux/module.h>
 #include <linux/of.h>
-#include <linux/of_platform.h>
 #include <linux/of_gpio.h>
+#include <linux/of_platform.h>
+#include <linux/platform_device.h>
 #include <linux/slab.h>
 #include <linux/workqueue.h>
-#include <linux/module.h>
-#include <linux/err.h>
 
 struct gpio_led_data {
         struct led_classdev cdev;
@@ -36,7 +36,7 @@ struct gpio_led_data {
 
 static void gpio_led_work(struct work_struct *work)
 {
-        struct gpio_led_data    *led_dat =
+        struct gpio_led_data *led_dat =
                 container_of(work, struct gpio_led_data, work);
 
         if (led_dat->blinking) {
@@ -235,14 +235,12 @@ static struct gpio_leds_priv *gpio_leds_create_of(struct platform_device *pdev)
 }
 #endif /* CONFIG_OF_GPIO */
 
-
 static int gpio_led_probe(struct platform_device *pdev)
 {
         struct gpio_led_platform_data *pdata = dev_get_platdata(&pdev->dev);
         struct gpio_leds_priv *priv;
         int i, ret = 0;
 
-
         if (pdata && pdata->num_leds) {
                 priv = devm_kzalloc(&pdev->dev,
                                 sizeof_gpio_leds_priv(pdata->num_leds),
diff --git a/drivers/leds/leds-lp3944.c b/drivers/leds/leds-lp3944.c
index 8e1abdcd4c9d..53144fb96167 100644
--- a/drivers/leds/leds-lp3944.c
+++ b/drivers/leds/leds-lp3944.c
@@ -335,7 +335,8 @@ static int lp3944_configure(struct i2c_client *client,
                         }
 
                         /* to expose the default value to userspace */
-                        led->ldev.brightness = led->status;
+                        led->ldev.brightness =
+                                        (enum led_brightness) led->status;
 
                         /* Set the default led status */
                         err = lp3944_led_set(led, led->status);
diff --git a/drivers/leds/trigger/ledtrig-gpio.c b/drivers/leds/trigger/ledtrig-gpio.c
index 35812e3a37f2..c86c41826476 100644
--- a/drivers/leds/trigger/ledtrig-gpio.c
+++ b/drivers/leds/trigger/ledtrig-gpio.c
@@ -48,7 +48,7 @@ static void gpio_trig_work(struct work_struct *work)
         if (!gpio_data->gpio)
                 return;
 
-        tmp = gpio_get_value(gpio_data->gpio);
+        tmp = gpio_get_value_cansleep(gpio_data->gpio);
         if (gpio_data->inverted)
                 tmp = !tmp;
 
diff --git a/include/linux/leds.h b/include/linux/leds.h
index e43686472197..a57611d0c94e 100644
--- a/include/linux/leds.h
+++ b/include/linux/leds.h
@@ -13,8 +13,8 @@
 #define __LINUX_LEDS_H_INCLUDED
 
 #include <linux/list.h>
-#include <linux/spinlock.h>
 #include <linux/rwsem.h>
+#include <linux/spinlock.h>
 #include <linux/timer.h>
 #include <linux/workqueue.h>
 
@@ -31,8 +31,8 @@ enum led_brightness {
 
 struct led_classdev {
         const char              *name;
-        int                      brightness;
-        int                      max_brightness;
+        enum led_brightness      brightness;
+        enum led_brightness      max_brightness;
         int                      flags;
 
         /* Lower 16 bits reflect status */
@@ -140,6 +140,16 @@ extern void led_blink_set_oneshot(struct led_classdev *led_cdev,
  */
 extern void led_set_brightness(struct led_classdev *led_cdev,
                                enum led_brightness brightness);
+/**
+ * led_update_brightness - update LED brightness
+ * @led_cdev: the LED to query
+ *
+ * Get an LED's current brightness and update led_cdev->brightness
+ * member with the obtained value.
+ *
+ * Returns: 0 on success or negative error value on failure
+ */
+extern int led_update_brightness(struct led_classdev *led_cdev);
 
 /*
  * LED Triggers