4.19-stable review patch. If anyone has any objections, please let me know. ------------------ From: Thomas Zimmermann <tzimmermann@xxxxxxx> commit 7b91d017f77c1bda56f27c2f4bbb70de7c6eca08 upstream. Struct gpio_backlight_platform_data refers to a platform device within the Linux device hierarchy. The test in gpio_backlight_check_fb() compares it against the fbdev device in struct fb_info.dev, which is different. Fix the test by comparing to struct fb_info.device. Fixes a bug in the backlight driver and prepares fbdev for making struct fb_info.dev optional. v2: * move renames into separate patch (Javier, Sam, Michael) Signed-off-by: Thomas Zimmermann <tzimmermann@xxxxxxx> Fixes: 8b770e3c9824 ("backlight: Add GPIO-based backlight driver") Cc: Laurent Pinchart <laurent.pinchart+renesas@xxxxxxxxxxxxxxxx> Cc: Rich Felker <dalias@xxxxxxxx> Cc: John Paul Adrian Glaubitz <glaubitz@xxxxxxxxxxxxxxxxxxx> Cc: Lee Jones <lee@xxxxxxxxxx> Cc: Daniel Thompson <daniel.thompson@xxxxxxxxxx> Cc: Jingoo Han <jingoohan1@xxxxxxxxx> Cc: linux-sh@xxxxxxxxxxxxxxx Cc: dri-devel@xxxxxxxxxxxxxxxxxxxxx Cc: <stable@xxxxxxxxxxxxxxx> # v3.12+ Reviewed-by: Sam Ravnborg <sam@xxxxxxxxxxxx> Reviewed-by: Daniel Thompson <daniel.thompson@xxxxxxxxxx> Link: https://patchwork.freedesktop.org/patch/msgid/20230613110953.24176-4-tzimmermann@xxxxxxx Signed-off-by: Greg Kroah-Hartman <gregkh@xxxxxxxxxxxxxxxxxxx> --- drivers/video/backlight/gpio_backlight.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) --- a/drivers/video/backlight/gpio_backlight.c +++ b/drivers/video/backlight/gpio_backlight.c @@ -48,7 +48,7 @@ static int gpio_backlight_check_fb(struc { struct gpio_backlight *gbl = bl_get_data(bl); - return gbl->fbdev == NULL || gbl->fbdev == info->dev; + return gbl->fbdev == NULL || gbl->fbdev == info->device; } static const struct backlight_ops gpio_backlight_ops = {