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@xxxxxxx>
> ---
> 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.
> };
>
> +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
>
--
Lee Jones [李琼斯]
