diff mbox series

[V2] video: backlight: Drop maximum brightness override for brightness zero

Message ID 20210713191633.121317-1-marex@denx.de
State New
Headers show
Series [V2] video: backlight: Drop maximum brightness override for brightness zero | expand

Commit Message

Marek Vasut July 13, 2021, 7:16 p.m. UTC
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 <noralf@tronnes.org>
Reviewed-by: Daniel Thompson <daniel.thompson@linaro.org>
Cc: <stable@vger.kernel.org> # 5.4+
Cc: <stable@vger.kernel.org> # 4.19.x: ec665b756e6f7: backlight: gpio-backlight: Correct initial power state handling
Signed-off-by: Marek Vasut <marex@denx.de>
Cc: Daniel Thompson <daniel.thompson@linaro.org>
Cc: Meghana Madhyastha <meghana.madhyastha@gmail.com>
Cc: Noralf Trønnes <noralf@tronnes.org>
Cc: Sean Paul <seanpaul@chromium.org>
Cc: Thierry Reding <treding@nvidia.com>
---
V2: Add AB/RB, CC stable
---
 drivers/video/backlight/backlight.c | 6 ------
 1 file changed, 6 deletions(-)

Comments

Marek Vasut Sept. 11, 2021, 6:40 p.m. UTC | #1
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 <noralf@tronnes.org>

> Reviewed-by: Daniel Thompson <daniel.thompson@linaro.org>

> Cc: <stable@vger.kernel.org> # 5.4+

> Cc: <stable@vger.kernel.org> # 4.19.x: ec665b756e6f7: backlight: gpio-backlight: Correct initial power state handling

> Signed-off-by: Marek Vasut <marex@denx.de>

> Cc: Daniel Thompson <daniel.thompson@linaro.org>

> Cc: Meghana Madhyastha <meghana.madhyastha@gmail.com>

> Cc: Noralf Trønnes <noralf@tronnes.org>

> Cc: Sean Paul <seanpaul@chromium.org>

> Cc: Thierry Reding <treding@nvidia.com>

> ---

> 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.
diff mbox series

Patch

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;
 		}
 	}