Re: [PATCH 2/2] leds: lp8864: Register a backlight device

On Mon, Aug 17, 2026 at 07:08:15PM +0200, A. Sverdlin wrote:

From: Alexander Sverdlin <alexander.sverdlin@siemens.com>

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.