[PATCH V2] video: backlight: Drop maximum brightness override for brightness zero - Linux-stable-mirror

13 Jul 2021

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;
    	}
    }
-- 
2.30.2


    