leds: gpio trigger: simplifications from core changes

The trigger core learned error handling for the activate callback and
to handle device attributes. Also make use of the module_led_trigger()
helper to simplify trigger registration.

Signed-off-by: Uwe Kleine-König <u.kleine-koenig@pengutronix.de>
Acked-by: Pavel Machek <pavel@ucw.cz>
Signed-off-by: Jacek Anaszewski <jacek.anaszewski@gmail.com>

drivers/leds/trigger/ledtrig-gpio.c

@@ -28,7 +28,7 @@ struct gpio_trig_data {
 static irqreturn_t gpio_trig_irq(int irq, void *_led)
 {
 	struct led_classdev *led = _led;
-	struct gpio_trig_data *gpio_data = led->trigger_data;
+	struct gpio_trig_data *gpio_data = led_get_trigger_data(led);
 	int tmp;
 
 	tmp = gpio_get_value_cansleep(gpio_data->gpio);
@@ -51,8 +51,7 @@ static irqreturn_t gpio_trig_irq(int irq, void *_led)
 static ssize_t gpio_trig_brightness_show(struct device *dev,
 		struct device_attribute *attr, char *buf)
 {
-	struct led_classdev *led = dev_get_drvdata(dev);
-	struct gpio_trig_data *gpio_data = led->trigger_data;
+	struct gpio_trig_data *gpio_data = led_trigger_get_drvdata(dev);
 
 	return sprintf(buf, "%u\n", gpio_data->desired_brightness);
 }
@@ -60,8 +59,7 @@ static ssize_t gpio_trig_brightness_show(struct device *dev,
 static ssize_t gpio_trig_brightness_store(struct device *dev,
 		struct device_attribute *attr, const char *buf, size_t n)
 {
-	struct led_classdev *led = dev_get_drvdata(dev);
-	struct gpio_trig_data *gpio_data = led->trigger_data;
+	struct gpio_trig_data *gpio_data = led_trigger_get_drvdata(dev);
 	unsigned desired_brightness;
 	int ret;
 
@@ -81,8 +79,7 @@ static DEVICE_ATTR(desired_brightness, 0644, gpio_trig_brightness_show,
 static ssize_t gpio_trig_inverted_show(struct device *dev,
 		struct device_attribute *attr, char *buf)
 {
-	struct led_classdev *led = dev_get_drvdata(dev);
-	struct gpio_trig_data *gpio_data = led->trigger_data;
+	struct gpio_trig_data *gpio_data = led_trigger_get_drvdata(dev);
 
 	return sprintf(buf, "%u\n", gpio_data->inverted);
 }
@@ -90,8 +87,8 @@ static ssize_t gpio_trig_inverted_show(struct device *dev,
 static ssize_t gpio_trig_inverted_store(struct device *dev,
 		struct device_attribute *attr, const char *buf, size_t n)
 {
-	struct led_classdev *led = dev_get_drvdata(dev);
-	struct gpio_trig_data *gpio_data = led->trigger_data;
+	struct led_classdev *led = led_trigger_get_led(dev);
+	struct gpio_trig_data *gpio_data = led_trigger_get_drvdata(dev);
 	unsigned long inverted;
 	int ret;
 
@@ -115,8 +112,7 @@ static DEVICE_ATTR(inverted, 0644, gpio_trig_inverted_show,
 static ssize_t gpio_trig_gpio_show(struct device *dev,
 		struct device_attribute *attr, char *buf)
 {
-	struct led_classdev *led = dev_get_drvdata(dev);
-	struct gpio_trig_data *gpio_data = led->trigger_data;
+	struct gpio_trig_data *gpio_data = led_trigger_get_drvdata(dev);
 
 	return sprintf(buf, "%u\n", gpio_data->gpio);
 }
@@ -124,8 +120,8 @@ static ssize_t gpio_trig_gpio_show(struct device *dev,
 static ssize_t gpio_trig_gpio_store(struct device *dev,
 		struct device_attribute *attr, const char *buf, size_t n)
 {
-	struct led_classdev *led = dev_get_drvdata(dev);
-	struct gpio_trig_data *gpio_data = led->trigger_data;
+	struct led_classdev *led = led_trigger_get_led(dev);
+	struct gpio_trig_data *gpio_data = led_trigger_get_drvdata(dev);
 	unsigned gpio;
 	int ret;
 
@@ -162,77 +158,44 @@ static ssize_t gpio_trig_gpio_store(struct device *dev,
 }
 static DEVICE_ATTR(gpio, 0644, gpio_trig_gpio_show, gpio_trig_gpio_store);
 
+static struct attribute *gpio_trig_attrs[] = {
+	&dev_attr_desired_brightness.attr,
+	&dev_attr_inverted.attr,
+	&dev_attr_gpio.attr,
+	NULL
+};
+ATTRIBUTE_GROUPS(gpio_trig);
+
 static int gpio_trig_activate(struct led_classdev *led)
 {
 	struct gpio_trig_data *gpio_data;
-	int ret;
 
 	gpio_data = kzalloc(sizeof(*gpio_data), GFP_KERNEL);
 	if (!gpio_data)
-		return 0;
-
-	ret = device_create_file(led->dev, &dev_attr_gpio);
-	if (ret)
-		goto err_gpio;
-
-	ret = device_create_file(led->dev, &dev_attr_inverted);
-	if (ret)
-		goto err_inverted;
-
-	ret = device_create_file(led->dev, &dev_attr_desired_brightness);
-	if (ret)
-		goto err_brightness;
+		return -ENOMEM;
 
 	gpio_data->led = led;
-	led->trigger_data = gpio_data;
-	led->activated = true;
-
-	return 0;
-
-err_brightness:
-	device_remove_file(led->dev, &dev_attr_inverted);
-
-err_inverted:
-	device_remove_file(led->dev, &dev_attr_gpio);
-
-err_gpio:
-	kfree(gpio_data);
+	led_set_trigger_data(led, gpio_data);
 
 	return 0;
 }
 
 static void gpio_trig_deactivate(struct led_classdev *led)
 {
-	struct gpio_trig_data *gpio_data = led->trigger_data;
+	struct gpio_trig_data *gpio_data = led_get_trigger_data(led);
 
-	if (led->activated) {
-		device_remove_file(led->dev, &dev_attr_gpio);
-		device_remove_file(led->dev, &dev_attr_inverted);
-		device_remove_file(led->dev, &dev_attr_desired_brightness);
-		if (gpio_data->gpio != 0)
-			free_irq(gpio_to_irq(gpio_data->gpio), led);
-		kfree(gpio_data);
-		led->activated = false;
-	}
+	if (gpio_data->gpio != 0)
+		free_irq(gpio_to_irq(gpio_data->gpio), led);
+	kfree(gpio_data);
 }
 
 static struct led_trigger gpio_led_trigger = {
 	.name		= "gpio",
 	.activate	= gpio_trig_activate,
 	.deactivate	= gpio_trig_deactivate,
+	.groups		= gpio_trig_groups,
 };
-
-static int __init gpio_trig_init(void)
-{
-	return led_trigger_register(&gpio_led_trigger);
-}
-module_init(gpio_trig_init);
-
-static void __exit gpio_trig_exit(void)
-{
-	led_trigger_unregister(&gpio_led_trigger);
-}
-module_exit(gpio_trig_exit);
+module_led_trigger(gpio_led_trigger);
 
 MODULE_AUTHOR("Felipe Balbi <me@felipebalbi.com>");
 MODULE_DESCRIPTION("GPIO LED trigger");