drm/fsl-dcu: fix alpha blending

Fix alpha blending by enabling alpha blending for the whole frame if
a color mode with alpha channel is selected (DRM_FORMAT_ARGB*). Also
support color modes without alpha channel (DRM_FORMAT_XRGB*) by just
not enabling alpha blending on layer level.

Signed-off-by: Stefan Agner <stefan@agner.ch>

diff --git a/drivers/gpu/drm/fsl-dcu/fsl_dcu_drm_drv.h b/drivers/gpu/drm/fsl-dcu/fsl_dcu_drm_drv.h
index 579b9e44e7645f7e28aa3894dde708cc88bdc900..6413ac9e47699a1e97b8f91531b96ad22987944f 100644 (file)
--- a/drivers/gpu/drm/fsl-dcu/fsl_dcu_drm_drv.h
+++ b/drivers/gpu/drm/fsl-dcu/fsl_dcu_drm_drv.h
@@ -133,7 +133,9 @@
 #define DCU_LAYER_RLE_EN               BIT(15)
 #define DCU_LAYER_LUOFFS(x)            ((x) << 4)
 #define DCU_LAYER_BB_ON                        BIT(2)
-#define DCU_LAYER_AB(x)                        (x)
+#define DCU_LAYER_AB_NONE              0
+#define DCU_LAYER_AB_CHROMA_KEYING     1
+#define DCU_LAYER_AB_WHOLE_FRAME       2
 
 #define DCU_LAYER_CKMAX_R(x)           ((x) << 16)
 #define DCU_LAYER_CKMAX_G(x)           ((x) << 8)

diff --git a/drivers/gpu/drm/fsl-dcu/fsl_dcu_drm_plane.c b/drivers/gpu/drm/fsl-dcu/fsl_dcu_drm_plane.c
index 1ea70314be1dcea25ebca6652f578fdd8011dd18..274558b3b32b2804c60695fe08ca0e4753c1bfad 100644 (file)
--- a/drivers/gpu/drm/fsl-dcu/fsl_dcu_drm_plane.c
+++ b/drivers/gpu/drm/fsl-dcu/fsl_dcu_drm_plane.c
@@ -47,8 +47,11 @@ static int fsl_dcu_drm_plane_atomic_check(struct drm_plane *plane,
        switch (fb->pixel_format) {
        case DRM_FORMAT_RGB565:
        case DRM_FORMAT_RGB888:
+       case DRM_FORMAT_XRGB8888:
        case DRM_FORMAT_ARGB8888:
-       case DRM_FORMAT_BGRA4444:
+       case DRM_FORMAT_XRGB4444:
+       case DRM_FORMAT_ARGB4444:
+       case DRM_FORMAT_XRGB1555:
        case DRM_FORMAT_ARGB1555:
        case DRM_FORMAT_YUV422:
                return 0;
@@ -81,7 +84,7 @@ static void fsl_dcu_drm_plane_atomic_update(struct drm_plane *plane,
        struct drm_plane_state *state = plane->state;
        struct drm_framebuffer *fb = plane->state->fb;
        struct drm_gem_cma_object *gem;
-       unsigned int alpha, bpp;
+       unsigned int alpha = DCU_LAYER_AB_NONE, bpp;
        int index;
 
        if (!fb)
@@ -96,27 +99,30 @@ static void fsl_dcu_drm_plane_atomic_update(struct drm_plane *plane,
        switch (fb->pixel_format) {
        case DRM_FORMAT_RGB565:
                bpp = FSL_DCU_RGB565;
-               alpha = 0xff;
                break;
        case DRM_FORMAT_RGB888:
                bpp = FSL_DCU_RGB888;
-               alpha = 0xff;
                break;
        case DRM_FORMAT_ARGB8888:
+               alpha = DCU_LAYER_AB_WHOLE_FRAME;
+               /* fall-through */
+       case DRM_FORMAT_XRGB8888:
                bpp = FSL_DCU_ARGB8888;
-               alpha = 0xff;
                break;
-       case DRM_FORMAT_BGRA4444:
+       case DRM_FORMAT_ARGB4444:
+               alpha = DCU_LAYER_AB_WHOLE_FRAME;
+               /* fall-through */
+       case DRM_FORMAT_XRGB4444:
                bpp = FSL_DCU_ARGB4444;
-               alpha = 0xff;
                break;
        case DRM_FORMAT_ARGB1555:
+               alpha = DCU_LAYER_AB_WHOLE_FRAME;
+               /* fall-through */
+       case DRM_FORMAT_XRGB1555:
                bpp = FSL_DCU_ARGB1555;
-               alpha = 0xff;
                break;
        case DRM_FORMAT_YUV422:
                bpp = FSL_DCU_YUV422;
-               alpha = 0xff;
                break;
        default:
                return;
@@ -132,9 +138,9 @@ static void fsl_dcu_drm_plane_atomic_update(struct drm_plane *plane,
                     DCU_CTRLDESCLN(index, 3), gem->paddr);
        regmap_write(fsl_dev->regmap, DCU_CTRLDESCLN(index, 4),
                     DCU_LAYER_EN |
-                    DCU_LAYER_TRANS(alpha) |
+                    DCU_LAYER_TRANS(0xff) |
                     DCU_LAYER_BPP(bpp) |
-                    DCU_LAYER_AB(0));
+                    alpha);
        regmap_write(fsl_dev->regmap, DCU_CTRLDESCLN(index, 5),
                     DCU_LAYER_CKMAX_R(0xFF) |
                     DCU_LAYER_CKMAX_G(0xFF) |
@@ -202,8 +208,11 @@ static const struct drm_plane_funcs fsl_dcu_drm_plane_funcs = {
 static const u32 fsl_dcu_drm_plane_formats[] = {
        DRM_FORMAT_RGB565,
        DRM_FORMAT_RGB888,
+       DRM_FORMAT_XRGB8888,
        DRM_FORMAT_ARGB8888,
+       DRM_FORMAT_XRGB4444,
        DRM_FORMAT_ARGB4444,
+       DRM_FORMAT_XRGB1555,
        DRM_FORMAT_ARGB1555,
        DRM_FORMAT_YUV422,
 };