leds: led-class: Add led_module_get() helper

Split out part of of_led_get() into a generic led_module_get() helper
function.

This is a preparation patch for adding a generic (non devicetree specific)
led_get() function.

Reviewed-by: Andy Shevchenko <andy.shevchenko@gmail.com>
Reviewed-by: Linus Walleij <linus.walleij@linaro.org>
Signed-off-by: Hans de Goede <hdegoede@redhat.com>
Signed-off-by: Lee Jones <lee@kernel.org>
Link: https://lore.kernel.org/r/20230120114524.408368-3-hdegoede@redhat.com

drivers/leds/led-class.c

@@ -215,6 +215,23 @@ static int led_resume(struct device *dev)
 
 static SIMPLE_DEV_PM_OPS(leds_class_dev_pm_ops, led_suspend, led_resume);
 
+static struct led_classdev *led_module_get(struct device *led_dev)
+{
+	struct led_classdev *led_cdev;
+
+	if (!led_dev)
+		return ERR_PTR(-EPROBE_DEFER);
+
+	led_cdev = dev_get_drvdata(led_dev);
+
+	if (!try_module_get(led_cdev->dev->parent->driver->owner)) {
+		put_device(led_cdev->dev);
+		return ERR_PTR(-ENODEV);
+	}
+
+	return led_cdev;
+}
+
 /**
  * of_led_get() - request a LED device via the LED framework
  * @np: device node to get the LED device from
@@ -226,7 +243,6 @@ static SIMPLE_DEV_PM_OPS(leds_class_dev_pm_ops, led_suspend, led_resume);
 struct led_classdev *of_led_get(struct device_node *np, int index)
 {
 	struct device *led_dev;
-	struct led_classdev *led_cdev;
 	struct device_node *led_node;
 
 	led_node = of_parse_phandle(np, "leds", index);
@@ -236,17 +252,7 @@ struct led_classdev *of_led_get(struct device_node *np, int index)
 	led_dev = class_find_device_by_of_node(leds_class, led_node);
 	of_node_put(led_node);
 
-	if (!led_dev)
-		return ERR_PTR(-EPROBE_DEFER);
-
-	led_cdev = dev_get_drvdata(led_dev);
-
-	if (!try_module_get(led_cdev->dev->parent->driver->owner)) {
-		put_device(led_cdev->dev);
-		return ERR_PTR(-ENODEV);
-	}
-
-	return led_cdev;
+	return led_module_get(led_dev);
 }
 EXPORT_SYMBOL_GPL(of_led_get);