[PATCH 6/6] leds: transient trigger: simplifications from core changes

[Uwe Kleine-König <u.kleine-koenig@xxxxxxxxxxxxxx>]

The trigger core learned error handling for the activate callback and
to handle device attributes. This allows to simplify the driver
considerably. Note that .deactivate is only called when .new_activate
succeeded, so the check for activated can go away.

Signed-off-by: Uwe Kleine-König <u.kleine-koenig@xxxxxxxxxxxxxx>
---
 drivers/leds/trigger/ledtrig-transient.c | 63 ++++++++----------------
 1 file changed, 20 insertions(+), 43 deletions(-)

diff --git a/drivers/leds/trigger/ledtrig-transient.c b/drivers/leds/trigger/ledtrig-transient.c
index 9d1769073562..0cd90bda857b 100644
--- a/drivers/leds/trigger/ledtrig-transient.c
+++ b/drivers/leds/trigger/ledtrig-transient.c
@@ -152,68 +152,45 @@ static DEVICE_ATTR(duration, 0644, transient_duration_show,
 		   transient_duration_store);
 static DEVICE_ATTR(state, 0644, transient_state_show, transient_state_store);
 
-static void transient_trig_activate(struct led_classdev *led_cdev)
+static struct attribute *transient_trig_attrs[] = {
+	&dev_attr_activate.attr,
+	&dev_attr_duration.attr,
+	&dev_attr_state.attr,
+	NULL
+};
+ATTRIBUTE_GROUPS(transient_trig);
+
+static int transient_trig_activate(struct led_classdev *led_cdev)
 {
-	int rc;
 	struct transient_trig_data *tdata;
 
 	tdata = kzalloc(sizeof(struct transient_trig_data), GFP_KERNEL);
-	if (!tdata) {
-		dev_err(led_cdev->dev,
-			"unable to allocate transient trigger\n");
-		return;
-	}
+	if (!tdata)
+		return -ENOMEM;
+
 	led_cdev->trigger_data = tdata;
 	tdata->led_cdev = led_cdev;
 
-	rc = device_create_file(led_cdev->dev, &dev_attr_activate);
-	if (rc)
-		goto err_out;
-
-	rc = device_create_file(led_cdev->dev, &dev_attr_duration);
-	if (rc)
-		goto err_out_duration;
-
-	rc = device_create_file(led_cdev->dev, &dev_attr_state);
-	if (rc)
-		goto err_out_state;
-
 	timer_setup(&tdata->timer, transient_timer_function, 0);
-	led_cdev->activated = true;
-
-	return;
-
-err_out_state:
-	device_remove_file(led_cdev->dev, &dev_attr_duration);
-err_out_duration:
-	device_remove_file(led_cdev->dev, &dev_attr_activate);
-err_out:
-	dev_err(led_cdev->dev, "unable to register transient trigger\n");
-	led_cdev->trigger_data = NULL;
-	kfree(tdata);
+
+	return 0;
 }
 
 static void transient_trig_deactivate(struct led_classdev *led_cdev)
 {
 	struct transient_trig_data *transient_data = led_cdev->trigger_data;
 
-	if (led_cdev->activated) {
-		del_timer_sync(&transient_data->timer);
-		led_set_brightness_nosleep(led_cdev,
-					transient_data->restore_state);
-		device_remove_file(led_cdev->dev, &dev_attr_activate);
-		device_remove_file(led_cdev->dev, &dev_attr_duration);
-		device_remove_file(led_cdev->dev, &dev_attr_state);
-		led_cdev->trigger_data = NULL;
-		led_cdev->activated = false;
-		kfree(transient_data);
-	}
+	del_timer_sync(&transient_data->timer);
+	led_set_brightness_nosleep(led_cdev,
+				   transient_data->restore_state);
+	kfree(transient_data);
 }
 
 static struct led_trigger transient_trigger = {
 	.name     = "transient",
-	.activate = transient_trig_activate,
+	.new_activate = transient_trig_activate,
 	.deactivate = transient_trig_deactivate,
+	.groups = transient_trig_groups,
 };
 
 static int __init transient_trig_init(void)
-- 
2.17.0