backlight: Add backlight_device parameter to check_fb

check_fb from backlight_ops lacks a reference to the backlight_device
that's being referred to. Add this parameter so a backlight_device
can be mapped to a single framebuffer, especially if the same driver
handles multiple devices on a single system.
Signed-off-by: Bruno Prémont <bonbons@linux-vserver.org>
Signed-off-by: Richard Purdie <rpurdie@linux.intel.com>

drivers/video/backlight/adx_bl.c

@@ -56,7 +56,7 @@ static int adx_backlight_get_brightness(struct backlight_device *bldev)
 	return brightness & 0xff;
 }
 
-static int adx_backlight_check_fb(struct fb_info *fb)
+static int adx_backlight_check_fb(struct backlight_device *bldev, struct fb_info *fb)
 {
 	return 1;
 }

drivers/video/backlight/backlight.c

@@ -38,7 +38,7 @@ static int fb_notifier_callback(struct notifier_block *self,
 	mutex_lock(&bd->ops_lock);
 	if (bd->ops)
 		if (!bd->ops->check_fb ||
-		    bd->ops->check_fb(evdata->info)) {
+		    bd->ops->check_fb(bd, evdata->info)) {
 			bd->props.fb_blank = *(int *)evdata->data;
 			if (bd->props.fb_blank == FB_BLANK_UNBLANK)
 				bd->props.state &= ~BL_CORE_FBBLANK;

include/linux/backlight.h

@@ -47,7 +47,7 @@ struct backlight_ops {
 	int (*get_brightness)(struct backlight_device *);
 	/* Check if given framebuffer device is the one bound to this backlight;
 	   return 0 if not, !=0 if it is. If NULL, backlight always matches the fb. */
-	int (*check_fb)(struct fb_info *);
+	int (*check_fb)(struct backlight_device *, struct fb_info *);
 };
 
 /* This structure defines all the properties of a backlight */