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

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

[Matthieu CASTET]

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);
-- 
2.15.0

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

[Jacek Anaszewski]

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);
> 

-- 
Best regards,
Jacek Anaszewski

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

[Jacek Anaszewski]

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);
>>
> 

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

[Matthieu CASTET]

Hi Jacek,

Le Sat, 23 Dec 2017 11:33:40 +0100,
Jacek Anaszewski <jacek.anaszewski@gmail.com> a écrit :

> 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/
> 

No problem ;)