drm/sun4i: Fix DE2 VI layer format support

DE2 VI layer doesn't support blending which means alpha channel is
ignored. Replace all formats with alpha with "don't care" (X) channel.

Fixes: 7480ba4d ("drm/sun4i: Add support for DE2 VI planes")
Acked-by: Maxime Ripard <mripard@kernel.org>
Signed-off-by: Jernej Skrabec <jernej.skrabec@siol.net>
Link: https://patchwork.freedesktop.org/patch/msgid/20200224173901.174016-4-jernej.skrabec@siol.net

drivers/gpu/drm/sun4i/sun8i_mixer.c

@@ -106,48 +106,104 @@ static const struct de2_fmt_info de2_formats[] = {
 		.rgb = true,
 		.csc = SUN8I_CSC_MODE_OFF,
 	},
+	{
+		/* for DE2 VI layer which ignores alpha */
+		.drm_fmt = DRM_FORMAT_XRGB4444,
+		.de2_fmt = SUN8I_MIXER_FBFMT_ARGB4444,
+		.rgb = true,
+		.csc = SUN8I_CSC_MODE_OFF,
+	},
 	{
 		.drm_fmt = DRM_FORMAT_ABGR4444,
 		.de2_fmt = SUN8I_MIXER_FBFMT_ABGR4444,
 		.rgb = true,
 		.csc = SUN8I_CSC_MODE_OFF,
 	},
+	{
+		/* for DE2 VI layer which ignores alpha */
+		.drm_fmt = DRM_FORMAT_XBGR4444,
+		.de2_fmt = SUN8I_MIXER_FBFMT_ABGR4444,
+		.rgb = true,
+		.csc = SUN8I_CSC_MODE_OFF,
+	},
 	{
 		.drm_fmt = DRM_FORMAT_RGBA4444,
 		.de2_fmt = SUN8I_MIXER_FBFMT_RGBA4444,
 		.rgb = true,
 		.csc = SUN8I_CSC_MODE_OFF,
 	},
+	{
+		/* for DE2 VI layer which ignores alpha */
+		.drm_fmt = DRM_FORMAT_RGBX4444,
+		.de2_fmt = SUN8I_MIXER_FBFMT_RGBA4444,
+		.rgb = true,
+		.csc = SUN8I_CSC_MODE_OFF,
+	},
 	{
 		.drm_fmt = DRM_FORMAT_BGRA4444,
 		.de2_fmt = SUN8I_MIXER_FBFMT_BGRA4444,
 		.rgb = true,
 		.csc = SUN8I_CSC_MODE_OFF,
 	},
+	{
+		/* for DE2 VI layer which ignores alpha */
+		.drm_fmt = DRM_FORMAT_BGRX4444,
+		.de2_fmt = SUN8I_MIXER_FBFMT_BGRA4444,
+		.rgb = true,
+		.csc = SUN8I_CSC_MODE_OFF,
+	},
 	{
 		.drm_fmt = DRM_FORMAT_ARGB1555,
 		.de2_fmt = SUN8I_MIXER_FBFMT_ARGB1555,
 		.rgb = true,
 		.csc = SUN8I_CSC_MODE_OFF,
 	},
+	{
+		/* for DE2 VI layer which ignores alpha */
+		.drm_fmt = DRM_FORMAT_XRGB1555,
+		.de2_fmt = SUN8I_MIXER_FBFMT_ARGB1555,
+		.rgb = true,
+		.csc = SUN8I_CSC_MODE_OFF,
+	},
 	{
 		.drm_fmt = DRM_FORMAT_ABGR1555,
 		.de2_fmt = SUN8I_MIXER_FBFMT_ABGR1555,
 		.rgb = true,
 		.csc = SUN8I_CSC_MODE_OFF,
 	},
+	{
+		/* for DE2 VI layer which ignores alpha */
+		.drm_fmt = DRM_FORMAT_XBGR1555,
+		.de2_fmt = SUN8I_MIXER_FBFMT_ABGR1555,
+		.rgb = true,
+		.csc = SUN8I_CSC_MODE_OFF,
+	},
 	{
 		.drm_fmt = DRM_FORMAT_RGBA5551,
 		.de2_fmt = SUN8I_MIXER_FBFMT_RGBA5551,
 		.rgb = true,
 		.csc = SUN8I_CSC_MODE_OFF,
 	},
+	{
+		/* for DE2 VI layer which ignores alpha */
+		.drm_fmt = DRM_FORMAT_RGBX5551,
+		.de2_fmt = SUN8I_MIXER_FBFMT_RGBA5551,
+		.rgb = true,
+		.csc = SUN8I_CSC_MODE_OFF,
+	},
 	{
 		.drm_fmt = DRM_FORMAT_BGRA5551,
 		.de2_fmt = SUN8I_MIXER_FBFMT_BGRA5551,
 		.rgb = true,
 		.csc = SUN8I_CSC_MODE_OFF,
 	},
+	{
+		/* for DE2 VI layer which ignores alpha */
+		.drm_fmt = DRM_FORMAT_BGRX5551,
+		.de2_fmt = SUN8I_MIXER_FBFMT_BGRA5551,
+		.rgb = true,
+		.csc = SUN8I_CSC_MODE_OFF,
+	},
 	{
 		.drm_fmt = DRM_FORMAT_ARGB2101010,
 		.de2_fmt = SUN8I_MIXER_FBFMT_ARGB2101010,

drivers/gpu/drm/sun4i/sun8i_vi_layer.c

@@ -398,26 +398,26 @@ static const struct drm_plane_funcs sun8i_vi_layer_funcs = {
 };
 
 /*
- * While all RGB formats are supported, VI planes don't support
- * alpha blending, so there is no point having formats with alpha
- * channel if their opaque analog exist.
+ * While DE2 VI layer supports same RGB formats as UI layer, alpha
+ * channel is ignored. This structure lists all unique variants
+ * where alpha channel is replaced with "don't care" (X) channel.
  */
 static const u32 sun8i_vi_layer_formats[] = {
-	DRM_FORMAT_ABGR1555,
-	DRM_FORMAT_ABGR4444,
-	DRM_FORMAT_ARGB1555,
-	DRM_FORMAT_ARGB4444,
 	DRM_FORMAT_BGR565,
 	DRM_FORMAT_BGR888,
-	DRM_FORMAT_BGRA5551,
-	DRM_FORMAT_BGRA4444,
+	DRM_FORMAT_BGRX4444,
+	DRM_FORMAT_BGRX5551,
 	DRM_FORMAT_BGRX8888,
 	DRM_FORMAT_RGB565,
 	DRM_FORMAT_RGB888,
-	DRM_FORMAT_RGBA4444,
-	DRM_FORMAT_RGBA5551,
+	DRM_FORMAT_RGBX4444,
+	DRM_FORMAT_RGBX5551,
 	DRM_FORMAT_RGBX8888,
+	DRM_FORMAT_XBGR1555,
+	DRM_FORMAT_XBGR4444,
 	DRM_FORMAT_XBGR8888,
+	DRM_FORMAT_XRGB1555,
+	DRM_FORMAT_XRGB4444,
 	DRM_FORMAT_XRGB8888,
 
 	DRM_FORMAT_NV16,