Re: [PATCH 10/13] leds: backlight trigger: Maintain global list of led backlight triggers

[Thomas Zimmermann <tzimmermann@suse.de>]

Hi

Am 11.02.25 um 15:00 schrieb Lee Jones:
> On Thu, 06 Feb 2025, Thomas Zimmermann wrote:
>
>> Maintain a list of led backlight triggers. This will replace the
>> fbdev notifiers that all backlight triggers currently subscribe to.
>>
>> Signed-off-by: Thomas Zimmermann <tzimmermann@suse.de>
>> ---
>>   drivers/leds/trigger/ledtrig-backlight.c | 13 +++++++++++++
>>   1 file changed, 13 insertions(+)
>>
>> diff --git a/drivers/leds/trigger/ledtrig-backlight.c b/drivers/leds/trigger/ledtrig-backlight.c
>> index 487577d22cfc..c1c1aa60cf07 100644
>> --- a/drivers/leds/trigger/ledtrig-backlight.c
>> +++ b/drivers/leds/trigger/ledtrig-backlight.c
>> @@ -23,8 +23,13 @@ struct bl_trig_notifier {
>>   	int old_status;
>>   	struct notifier_block notifier;
>>   	unsigned invert;
>> +
>> +	struct list_head entry;
> You don't appear to be doing anything with the list here.
>
> It would be better if you introduced the list when it's first utilised.

That's patch 12. I'll merge them.

Best regards
Thomas

>
>>   };
>>   
>> +static struct list_head ledtrig_backlight_list;
>> +static struct mutex ledtrig_backlight_list_mutex;
>> +
>>   static int fb_notifier_callback(struct notifier_block *p,
>>   				unsigned long event, void *data)
>>   {
>> @@ -118,6 +123,10 @@ static int bl_trig_activate(struct led_classdev *led)
>>   	if (ret)
>>   		dev_err(led->dev, "unable to register backlight trigger\n");
>>   
>> +	mutex_lock(&ledtrig_backlight_list_mutex);
>> +	list_add(&n->entry, &ledtrig_backlight_list);
>> +	mutex_unlock(&ledtrig_backlight_list_mutex);
>> +
>>   	return 0;
>>   }
>>   
>> @@ -125,6 +134,10 @@ static void bl_trig_deactivate(struct led_classdev *led)
>>   {
>>   	struct bl_trig_notifier *n = led_get_trigger_data(led);
>>   
>> +	mutex_lock(&ledtrig_backlight_list_mutex);
>> +	list_del(&n->entry);
>> +	mutex_unlock(&ledtrig_backlight_list_mutex);
>> +
>>   	fb_unregister_client(&n->notifier);
>>   	kfree(n);
>>   }
>> -- 
>> 2.48.1
>>

-- 
--
Thomas Zimmermann
Graphics Driver Developer
SUSE Software Solutions Germany GmbH
Frankenstrasse 146, 90461 Nuernberg, Germany
GF: Ivo Totev, Andrew Myers, Andrew McDonald, Boudien Moerman
HRB 36809 (AG Nuernberg)