Re: [PATCH 2/2] leds: lp8864: Register a backlight device
From: Daniel Thompson
Date: Mon Aug 24 2026 - 05:39:33 EST
On Mon, Aug 17, 2026 at 07:08:15PM +0200, A. Sverdlin wrote:
> From: Alexander Sverdlin <alexander.sverdlin@xxxxxxxxxxx>
>
> The LP8864/LP8866 is a display-cluster LED backlight driver. Expose a
> standard backlight class interface in addition to the LED class device,
> so it can be used by display/panel stacks that expect a backlight.
>
> Use the new devm_led_backlight_register() helper, which spawns a
> led-backlight device driven by our LED and tied to the I2C device
> lifetime. This keeps the driver a plain LED driver, requires no
> device-tree changes and remains backwards compatible with existing DTs.
> It is a no-op when the led-backlight support is not enabled.
... but when led-backlight support is enabled it will prohibit the use
of the LED sysfs interface.
Having zero DT changes is a nice property but it seems rather fragile to
change the ABI the userspace must use to manipulate the LED based on
CONFIG_LED_BL.
Is there no way to explictly configure which ABI should be used?
Daniel.