Re: [PATCH] led: core: Fix brightness setting when setting active_off=0

[Jacek Anaszewski <jacek.anaszewski@gmail.com>]

Hi Matthieu,

I was to send this fix for 4.15-rc5, but just realized the
possible mistake in the subject. Would you mind if I did
the following amendment?:

s/active_off/delay_off/

-- 
Best regards,
Jacek Anaszewski

On 12/13/2017 09:16 PM, Jacek Anaszewski wrote:
> Hi Matthieu,
> 
> Thanks for catching this. Applied.
> 
> On 12/12/2017 11:10 AM, Matthieu CASTET wrote:
>> With the current code, the following sequence won't work :
>> echo timer > trigger
>>
>> echo 0 >  delay_off
>> * at this point we call
>> ** led_delay_off_store
>> ** led_blink_set
>> *** stop timer
>> ** led_blink_setup
>> ** led_set_software_blink
>> *** if !delay_on, led off
>> *** if !delay_off, set led_set_brightness_nosleep <--- LED_BLINK_SW is set but timer is stop
>> *** otherwise start timer/set LED_BLINK_SW flag
>>
>> echo xxx > brightness
>> * led_set_brightness
>> ** if LED_BLINK_SW
>> *** if brightness=0, led off
>> *** else apply brightness if next timer <--- timer is stop, and will never apply new setting
>> ** otherwise set led_set_brightness_nosleep
>>
>> To fix that, when we delete the timer, we should clear LED_BLINK_SW.
>>
>> Cc: linux-leds@vger.kernel.org
>> Signed-off-by: Matthieu CASTET <matthieu.castet@parrot.com>
>> ---
>>  drivers/leds/led-core.c | 2 +-
>>  1 file changed, 1 insertion(+), 1 deletion(-)
>>
>> diff --git a/drivers/leds/led-core.c b/drivers/leds/led-core.c
>> index fd83c7f77a95..f3654fd2eaf3 100644
>> --- a/drivers/leds/led-core.c
>> +++ b/drivers/leds/led-core.c
>> @@ -186,7 +186,7 @@ void led_blink_set(struct led_classdev *led_cdev,
>>  		   unsigned long *delay_on,
>>  		   unsigned long *delay_off)
>>  {
>> -	del_timer_sync(&led_cdev->blink_timer);
>> +	led_stop_software_blink(led_cdev);
>>  
>>  	clear_bit(LED_BLINK_ONESHOT, &led_cdev->work_flags);
>>  	clear_bit(LED_BLINK_ONESHOT_STOP, &led_cdev->work_flags);
>>
>