leds: triggers: let struct led_trigger::activate() return an error code

Given that activating a trigger can fail, let the callback return an
indication. This prevents to have a trigger active according to the
"trigger" sysfs attribute but not functional.

All users are changed accordingly to return 0 for now. There is no intended
change in behaviour.

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>

1 files changed, 5 insertions, 3 deletions

diff --git a/drivers/leds/trigger/ledtrig-timer.c b/drivers/leds/trigger/ledtrig-timer.c
index 10fc0966b0e3..527055d815ad 100644
--- a/drivers/leds/trigger/ledtrig-timer.c
+++ b/drivers/leds/trigger/ledtrig-timer.c
@@ -70,7 +70,7 @@ static ssize_t led_delay_off_store(struct device *dev,
 static DEVICE_ATTR(delay_on, 0644, led_delay_on_show, led_delay_on_store);
 static DEVICE_ATTR(delay_off, 0644, led_delay_off_show, led_delay_off_store);
 
-static void timer_trig_activate(struct led_classdev *led_cdev)
+static int timer_trig_activate(struct led_classdev *led_cdev)
 {
         int rc;
 
@@ -78,7 +78,7 @@ static void timer_trig_activate(struct led_classdev *led_cdev)
 
         rc = device_create_file(led_cdev->dev, &dev_attr_delay_on);
         if (rc)
-                return;
+                return 0;
         rc = device_create_file(led_cdev->dev, &dev_attr_delay_off);
         if (rc)
                 goto err_out_delayon;
@@ -87,10 +87,12 @@ static void timer_trig_activate(struct led_classdev *led_cdev)
                       &led_cdev->blink_delay_off);
         led_cdev->activated = true;
 
-        return;
+        return 0;
 
 err_out_delayon:
         device_remove_file(led_cdev->dev, &dev_attr_delay_on);
+
+        return 0;
 }
 
 static void timer_trig_deactivate(struct led_classdev *led_cdev)