Re: [PATCH 1/2] video: always update the brightness when poking "brightness"

[Matthew Garrett <mjg59@srcf.ucam.org>]

Richard, how about something like this? If the hardware changes the 
state of the backlight behind us, the current code may make it 
impossible to set it back to the previous state without resynchronising 
the value first. Is there any currently supported hardware where this 
would be a sufficiently expensive or disruptive operation to warrant the 
check?

diff --git a/drivers/video/backlight/backlight.c b/drivers/video/backlight/backlight.c
index fab0bc8..064b428 100644
--- a/drivers/video/backlight/backlight.c
+++ b/drivers/video/backlight/backlight.c
@@ -134,10 +134,8 @@ static ssize_t backlight_store_brightness(struct device *dev,
 		else {
 			pr_debug("backlight: set brightness to %d\n",
 				 brightness);
-			if (bd->props.brightness != brightness) {
-				bd->props.brightness = brightness;
-				backlight_update_status(bd);
-			}
+			bd->props.brightness = brightness;
+			backlight_update_status(bd);
 			rc = count;
 		}
 	}

-- 
Matthew Garrett | mjg59@srcf.ucam.org