On Fri, 14 Mar 2025, Craig McQueen wrote:
> Accept "default" written to sysfs trigger attr.
> If the text "default" is written to the LED's sysfs 'trigger' attr, then
> call led_trigger_set_default() to set the LED to its default trigger.
>
> If the default trigger is set to "none", then led_trigger_set_default()
> will remove a trigger. This is in contrast to the default trigger being
> unset, in which case led_trigger_set_default() does nothing.
I can't take this without a SoB.
It would be nice to have Jacek's Reviewed-by at this point too.
> ---
> Documentation/ABI/testing/sysfs-class-led | 6 ++++++
> drivers/leds/led-triggers.c | 13 +++++++++++++
> 2 files changed, 19 insertions(+)
>
> diff --git a/Documentation/ABI/testing/sysfs-class-led b/Documentation/ABI/testing/sysfs-class-led
> index 2e24ac3bd7ef..0313b82644f2 100644
> --- a/Documentation/ABI/testing/sysfs-class-led
> +++ b/Documentation/ABI/testing/sysfs-class-led
> @@ -72,6 +72,12 @@ Description:
> /sys/class/leds/<led> once a given trigger is selected. For
> their documentation see `sysfs-class-led-trigger-*`.
>
> + Writing "none" removes the trigger for this LED.
> +
> + Writing "default" sets the trigger to the LED's default trigger
> + (which would often be configured in the device tree for the
> + hardware).
> +
> What: /sys/class/leds/<led>/inverted
> Date: January 2011
> KernelVersion: 2.6.38
> diff --git a/drivers/leds/led-triggers.c b/drivers/leds/led-triggers.c
> index b2d40f87a5ff..3799dcc1cf07 100644
> --- a/drivers/leds/led-triggers.c
> +++ b/drivers/leds/led-triggers.c
> @@ -54,6 +54,11 @@ ssize_t led_trigger_write(struct file *filp, struct kobject *kobj,
> goto unlock;
> }
>
> + if (sysfs_streq(buf, "default")) {
> + led_trigger_set_default(led_cdev);
> + goto unlock;
> + }
> +
> down_read(&triggers_list_lock);
> list_for_each_entry(trig, &trigger_list, next_trig) {
> if (sysfs_streq(buf, trig->name) && trigger_relevant(led_cdev, trig)) {
> @@ -98,6 +103,9 @@ static int led_trigger_format(char *buf, size_t size,
> int len = led_trigger_snprintf(buf, size, "%s",
> led_cdev->trigger ? "none" : "[none]");
>
> + if (led_cdev->default_trigger)
> + len += led_trigger_snprintf(buf + len, size - len, " default");
> +
> list_for_each_entry(trig, &trigger_list, next_trig) {
> bool hit;
>
> @@ -281,6 +289,11 @@ void led_trigger_set_default(struct led_classdev *led_cdev)
> if (!led_cdev->default_trigger)
> return;
>
> + if (!strcmp(led_cdev->default_trigger, "none")) {
> + led_trigger_remove(led_cdev);
> + return;
> + }
> +
> down_read(&triggers_list_lock);
> down_write(&led_cdev->trigger_lock);
> list_for_each_entry(trig, &trigger_list, next_trig) {
> --
> 2.48.1
>
>
--
Lee Jones [李琼斯]
