On 5/20/22 12:11, Eddie James wrote:
If an LED is blinking through the hardware and the trigger is deactivated,
the driver will set the brightness to 0 to disable blinking. However, if
the LED driver doesn't support non-blocking operations, the request for
setting brightness to 0 will get queued. Then if a user requests a new
non-zero brightness before the request for 0 brightness is executed, the
LED blinking will not get disabled since the brightness will simply be
updated.
Fix this by flushing the workqueue before updating the requested
brightness.
I just realized this never made it anywhere. Pavel, any thoughts?
Thanks,
Eddie
Fixes: 4d71a4a12b13 ("leds: Add support for setting brightness in a synchronous way")
Signed-off-by: Eddie James <eajames@xxxxxxxxxxxxx>
---
drivers/leds/led-class.c | 2 ++
1 file changed, 2 insertions(+)
diff --git a/drivers/leds/led-class.c b/drivers/leds/led-class.c
index 6a8ea94834fa..861a1cb5df5b 100644
--- a/drivers/leds/led-class.c
+++ b/drivers/leds/led-class.c
@@ -55,6 +55,8 @@ static ssize_t brightness_store(struct device *dev,
if (state == LED_OFF)
led_trigger_remove(led_cdev);
+ /* flush out any request to disable blinking */
+ flush_work(&led_cdev->set_brightness_work);
led_set_brightness(led_cdev, state);
flush_work(&led_cdev->set_brightness_work);
