Commit d84d80f3 authored by Heiner Kallweit's avatar Heiner Kallweit Committed by Jacek Anaszewski
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leds: core: avoid error message when a USB LED device is unplugged 



When a USB LED device is unplugged the remove call chain calls
led_classdev_unregister which tries to switch the LED off.
As the device has been removed already this results in a ENODEV
error message in dmesg.
Avoid this error message by ignoring ENODEV in calls from
led_classdev_unregister if the LED device is flagged as pluggable.

Therefore a new flag LED_HW_PLUGGABLE was introduced which should be set by
all LED drivers handling pluggable LED devices (mainly USB LED devices).

Signed-off-by: default avatarHeiner Kallweit <hkallweit1@gmail.com>
Signed-off-by: default avatarJacek Anaszewski <j.anaszewski@samsung.com>
parent 70b2563b

drivers/leds/led-class.c

+2 −0
Original line number Diff line number Diff line
@@ -245,6 +245,8 @@ void led_classdev_unregister(struct led_classdev *led_cdev) 
	up_write(&led_cdev->trigger_lock);

#endif



	led_cdev->flags |= LED_UNREGISTERING;



	/* Stop blinking */

	led_stop_software_blink(led_cdev);

drivers/leds/led-core.c

+4 −1
Original line number Diff line number Diff line
@@ -98,7 +98,10 @@ static void set_brightness_delayed(struct work_struct *ws) 
						led_cdev->delayed_set_value);

	else

		ret = -ENOTSUPP;

	if (ret < 0)

	if (ret < 0 &&

	    /* LED HW might have been unplugged, therefore don't warn */

	    !(ret == -ENODEV && (led_cdev->flags & LED_UNREGISTERING) &&

	    (led_cdev->flags & LED_HW_PLUGGABLE)))

		dev_err(led_cdev->dev,

			"Setting an LED's brightness failed (%d)\n", ret);

}

include/linux/leds.h

+2 −0
Original line number Diff line number Diff line
@@ -39,6 +39,7 @@ struct led_classdev { 


	/* Lower 16 bits reflect status */

#define LED_SUSPENDED		(1 << 0)

#define LED_UNREGISTERING	(1 << 1)

	/* Upper 16 bits reflect control information */

#define LED_CORE_SUSPENDRESUME	(1 << 16)

#define LED_BLINK_ONESHOT	(1 << 17)
@@ -48,6 +49,7 @@ struct led_classdev { 
#define LED_BLINK_DISABLE	(1 << 21)

#define LED_SYSFS_DISABLE	(1 << 22)

#define LED_DEV_CAP_FLASH	(1 << 23)

#define LED_HW_PLUGGABLE	(1 << 24)



	/* Set LED brightness level

	 * Must not sleep. Use brightness_set_blocking for drivers

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