[PATCH 5.14 815/849] video: backlight: Drop maximum brightness override for brightness zero

From: Greg Kroah-Hartman
Date: Mon Nov 15 2021 - 18:26:03 EST


From: Marek Vasut <marex@xxxxxxx>

commit 33a5471f8da976bf271a1ebbd6b9d163cb0cb6aa upstream.

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")
Cc: <stable@xxxxxxxxxxxxxxx> # 5.4+
Cc: <stable@xxxxxxxxxxxxxxx> # 4.19.x: ec665b756e6f7: backlight: gpio-backlight: Correct initial power state handling
Signed-off-by: Marek Vasut <marex@xxxxxxx>
Acked-by: Noralf Trønnes <noralf@xxxxxxxxxxx>
Reviewed-by: Daniel Thompson <daniel.thompson@xxxxxxxxxx>
Signed-off-by: Lee Jones <lee.jones@xxxxxxxxxx>
Signed-off-by: Greg Kroah-Hartman <gregkh@xxxxxxxxxxxxxxxxxxx>
---
drivers/video/backlight/backlight.c | 6 ------
1 file changed, 6 deletions(-)

--- a/drivers/video/backlight/backlight.c
+++ b/drivers/video/backlight/backlight.c
@@ -688,12 +688,6 @@ static struct backlight_device *of_find_
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;
}
}