When registering a LED device we have the option to set a default trigger.
Depending on load order of drivers this trigger may not be available yet.
(affected LED device in my case: a DT-configured GPIO LED)
So far if the default trigger can't be found this error is silently
ignored.
Let's change this to return EPROBE_DEFER if the default trigger can't be
found. This gives the system the chance to probe the LED device later
once the trigger is available.
Signed-off-by: Heiner Kallweit <hkallweit1@xxxxxxxxx>
---
---
drivers/leds/led-class.c | 6 +++++-
drivers/leds/led-triggers.c | 11 ++++++++---
include/linux/leds.h | 5 +++--
3 files changed, 16 insertions(+), 6 deletions(-)
diff --git a/drivers/leds/led-class.c b/drivers/leds/led-class.c
index f2b0a80a..efe4f5a3 100644
--- a/drivers/leds/led-class.c
+++ b/drivers/leds/led-class.c
@@ -295,7 +295,11 @@ int led_classdev_register(struct device *parent, struct led_classdev *led_cdev)
led_init_core(led_cdev);
#ifdef CONFIG_LEDS_TRIGGERS
- led_trigger_set_default(led_cdev);
+ ret = led_trigger_set_default(led_cdev);
+ if (ret) {
+ led_classdev_unregister(led_cdev);
+ return ret;
+ }
#endif
dev_dbg(parent, "Registered led device: %s\n",
diff --git a/drivers/leds/led-triggers.c b/drivers/leds/led-triggers.c
index 431123b0..bad9e986 100644
--- a/drivers/leds/led-triggers.c
+++ b/drivers/leds/led-triggers.c
@@ -157,21 +157,26 @@ void led_trigger_remove(struct led_classdev *led_cdev)
}
EXPORT_SYMBOL_GPL(led_trigger_remove);
-void led_trigger_set_default(struct led_classdev *led_cdev)
+int led_trigger_set_default(struct led_classdev *led_cdev)
{
struct led_trigger *trig;
+ int ret = -EPROBE_DEFER;
if (!led_cdev->default_trigger)
- return;
+ return 0;
down_read(&triggers_list_lock);
down_write(&led_cdev->trigger_lock);
list_for_each_entry(trig, &trigger_list, next_trig) {
- if (!strcmp(led_cdev->default_trigger, trig->name))
+ if (!strcmp(led_cdev->default_trigger, trig->name)) {
led_trigger_set(led_cdev, trig);
+ ret = 0;
+ }
}
up_write(&led_cdev->trigger_lock);
up_read(&triggers_list_lock);
+
+ return ret;
}
EXPORT_SYMBOL_GPL(led_trigger_set_default);
diff --git a/include/linux/leds.h b/include/linux/leds.h
index 38c0bd7c..3e36ce31 100644
--- a/include/linux/leds.h
+++ b/include/linux/leds.h
@@ -280,7 +280,7 @@ extern void led_trigger_blink_oneshot(struct led_trigger *trigger,
unsigned long *delay_on,
unsigned long *delay_off,
int invert);
-extern void led_trigger_set_default(struct led_classdev *led_cdev);
+extern int led_trigger_set_default(struct led_classdev *led_cdev);
extern void led_trigger_set(struct led_classdev *led_cdev,
struct led_trigger *trigger);
extern void led_trigger_remove(struct led_classdev *led_cdev);
@@ -326,7 +326,8 @@ static inline void led_trigger_blink_oneshot(struct led_trigger *trigger,
unsigned long *delay_on,
unsigned long *delay_off,
int invert) {}
-static inline void led_trigger_set_default(struct led_classdev *led_cdev) {}
+static inline int led_trigger_set_default(struct led_classdev *led_cdev)
+ { return 0; }
static inline void led_trigger_set(struct led_classdev *led_cdev,
struct led_trigger *trigger) {}
static inline void led_trigger_remove(struct led_classdev *led_cdev) {}
--
2.11.1
