usb: simplify usbport trigger

The led trigger core learned a few things that allow to simplify the
trigger drivers.  Make use of automated trigger attributes and error
checking of the activate callback. Also use the wrappers to set and get
trigger_data.

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

drivers/usb/core/ledtrig-usbport.c

@@ -113,11 +113,17 @@ static ssize_t usbport_trig_port_store(struct device *dev,
 static struct attribute *ports_attrs[] = {
 	NULL,
 };
+
 static const struct attribute_group ports_group = {
 	.name = "ports",
 	.attrs = ports_attrs,
 };
 
+static const struct attribute_group *ports_groups[] = {
+	&ports_group,
+	NULL
+};
+
 /***************************************
  * Adding & removing ports
  ***************************************/
@@ -301,59 +307,44 @@ static int usbport_trig_notify(struct notifier_block *nb, unsigned long action,
 static int usbport_trig_activate(struct led_classdev *led_cdev)
 {
 	struct usbport_trig_data *usbport_data;
-	int err;
 
 	usbport_data = kzalloc(sizeof(*usbport_data), GFP_KERNEL);
 	if (!usbport_data)
-		return 0;
+		return -ENOMEM;
 	usbport_data->led_cdev = led_cdev;
 
 	/* List of ports */
 	INIT_LIST_HEAD(&usbport_data->ports);
-	err = sysfs_create_group(&led_cdev->dev->kobj, &ports_group);
-	if (err)
-		goto err_free;
 	usb_for_each_dev(usbport_data, usbport_trig_add_usb_dev_ports);
 	usbport_trig_update_count(usbport_data);
 
 	/* Notifications */
-	usbport_data->nb.notifier_call = usbport_trig_notify,
-	led_cdev->trigger_data = usbport_data;
+	usbport_data->nb.notifier_call = usbport_trig_notify;
+	led_set_trigger_data(led_cdev, usbport_data);
 	usb_register_notify(&usbport_data->nb);
 
-	led_cdev->activated = true;
-	return 0;
-
-err_free:
-	kfree(usbport_data);
 	return 0;
 }
 
 static void usbport_trig_deactivate(struct led_classdev *led_cdev)
 {
-	struct usbport_trig_data *usbport_data = led_cdev->trigger_data;
+	struct usbport_trig_data *usbport_data = led_get_trigger_data(led_cdev);
 	struct usbport_trig_port *port, *tmp;
 
-	if (!led_cdev->activated)
-		return;
-
 	list_for_each_entry_safe(port, tmp, &usbport_data->ports, list) {
 		usbport_trig_remove_port(usbport_data, port);
 	}
 
 	usb_unregister_notify(&usbport_data->nb);
 
-	sysfs_remove_group(&led_cdev->dev->kobj, &ports_group);
-
 	kfree(usbport_data);
-
-	led_cdev->activated = false;
 }
 
 static struct led_trigger usbport_led_trigger = {
 	.name     = "usbport",
 	.activate = usbport_trig_activate,
 	.deactivate = usbport_trig_deactivate,
+	.groups = ports_groups,
 };
 
 static int __init usbport_trig_init(void)