# Re: \[PATCH V2\] video: backlight: Drop maximum brightness override for brightness zero

- From: Marek Vasut \<marex@denx.de\>
- Date: 2021-09-11 18:40:59 
- List: linux-fbdev
- Page: https://ratatoskr.run/linux-fbdev/2021/09/6884157
- Thread: https://ratatoskr.run/dri-devel/2021/07/6881225/t.md

```text
On 7/13/21 9:16 PM, Marek Vasut wrote:
> The note in c2adda27d202f ("video: backlight: Add of_find_backlight helper
> in backlight.c") says that gpio-backlight uses brightness as power state.
> This has been fixed since in ec665b756e6f7 ("backlight: gpio-backlight:
> Correct initial power state handling") and other backlight drivers do not
> require this workaround. Drop the workaround.
>
> This fixes the case where e.g. pwm-backlight can perfectly well be set to
> brightness 0 on boot in DT, which without this patch leads to the display
> brightness to be max instead of off.
>
> Fixes: c2adda27d202f ("video: backlight: Add of_find_backlight helper in backlight.c")
> Acked-by: Noralf Trønnes <redacted>
> Reviewed-by: Daniel Thompson <redacted>
> Cc: <redacted> # 5.4+
> Cc: <redacted> # 4.19.x: ec665b756e6f7: backlight: gpio-backlight: Correct initial power state handling
> Signed-off-by: Marek Vasut <marex@denx.de>
> Cc: Daniel Thompson <redacted>
> Cc: Meghana Madhyastha <redacted>
> Cc: Noralf Trønnes <redacted>
> Cc: Sean Paul <redacted>
> Cc: Thierry Reding <redacted>
> ---
> V2: Add AB/RB, CC stable
> ---
>   drivers/video/backlight/backlight.c | 6 ------
>   1 file changed, 6 deletions(-)
>
> diff --git a/drivers/video/backlight/backlight.c b/drivers/video/backlight/backlight.c
> index 537fe1b376ad7..fc990e576340b 100644
> --- a/drivers/video/backlight/backlight.c
> +++ b/drivers/video/backlight/backlight.c
> @@ -688,12 +688,6 @@ static struct backlight_device *of_find_backlight(struct device *dev)
>   			of_node_put(np);
>   			if (!bd)
>   				return ERR_PTR(-EPROBE_DEFER);
> -			/*
> -			 * Note: gpio_backlight uses brightness as
> -			 * power state during probe
> -			 */
> -			if (!bd->props.brightness)
> -				bd->props.brightness = bd->props.max_brightness;
>   		}
>   	}
>   
>

Any news on this ?

Expanding CC list.
```