4.9-stable review patch. If anyone has any objections, please let me know. ------------------ From: Christophe JAILLET <christophe.jaillet@xxxxxxxxxx> [ Upstream commit 0f0861e31e3c59ca4bc1ec59d99260cfca79740e ] If 'sun4i_backend_drm_format_to_layer()' does not return 0, then 'val' is left unmodified. As it is not initialized either, the return value can be anything. It is likely that returning the error code was expected here. As the only caller of 'sun4i_backend_update_layer_formats()' does not check the return value, this fix is purely theorical. Signed-off-by: Christophe JAILLET <christophe.jaillet@xxxxxxxxxx> Signed-off-by: Maxime Ripard <maxime.ripard@xxxxxxxxxxxxxxxxxx> Signed-off-by: Sasha Levin <alexander.levin@xxxxxxxxxxx> Signed-off-by: Greg Kroah-Hartman <gregkh@xxxxxxxxxxxxxxxxxxx> --- drivers/gpu/drm/sun4i/sun4i_backend.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) --- a/drivers/gpu/drm/sun4i/sun4i_backend.c +++ b/drivers/gpu/drm/sun4i/sun4i_backend.c @@ -172,7 +172,7 @@ int sun4i_backend_update_layer_formats(s ret = sun4i_backend_drm_format_to_layer(plane, fb->pixel_format, &val); if (ret) { DRM_DEBUG_DRIVER("Invalid format\n"); - return val; + return ret; } regmap_update_bits(backend->regs, SUN4I_BACKEND_ATTCTL_REG1(layer),