The plane's opacity should be reseted while the plane is disabled. It prevents from seeing a possible global or layer background color set earlier. Signed-off-by: Yannick Fertre <yannick.fertre@xxxxxxxxxxx> --- drivers/gpu/drm/stm/ltdc.c | 3 +++ 1 file changed, 3 insertions(+) diff --git a/drivers/gpu/drm/stm/ltdc.c b/drivers/gpu/drm/stm/ltdc.c index 5576fdae4962..cb4f08673a64 100644 --- a/drivers/gpu/drm/stm/ltdc.c +++ b/drivers/gpu/drm/stm/ltdc.c @@ -1514,6 +1514,9 @@ static void ltdc_plane_atomic_disable(struct drm_plane *plane, /* Disable layer */ regmap_write_bits(ldev->regmap, LTDC_L1CR + lofs, LXCR_LEN | LXCR_CLUTEN | LXCR_HMEN, 0); + /* Reset the layer transparency to hide any related background color */ + regmap_write_bits(ldev->regmap, LTDC_L1CACR + lofs, LXCACR_CONSTA, 0x00); + /* Commit shadow registers = update plane at next vblank */ if (ldev->caps.plane_reg_shadow) regmap_write_bits(ldev->regmap, LTDC_L1RCR + lofs, -- 2.34.1