3 files changed, 24 insertions, 20 deletions

diff --git a/drivers/gpu/drm/sti/sti_drm_plane.c b/drivers/gpu/drm/sti/sti_drm_plane.c
index 64d4ed43dda3..5427bc28f205 100644
--- a/drivers/gpu/drm/sti/sti_drm_plane.c
+++ b/drivers/gpu/drm/sti/sti_drm_plane.c
@@ -15,17 +15,16 @@
 #include "sti_drm_plane.h"
 #include "sti_vtg.h"
 
+/* (Background) < GDP0 < GDP1 < VID0 < VID1 < GDP2 < GDP3 < (ForeGround) */
 enum sti_layer_desc sti_layer_default_zorder[] = {
         STI_GDP_0,
-        STI_VID_0,
         STI_GDP_1,
+        STI_VID_0,
         STI_VID_1,
         STI_GDP_2,
         STI_GDP_3,
 };
 
-/* (Background) < GDP0 < VID0 < GDP1 < VID1 < GDP2 < GDP3 < (ForeGround) */
-
 static int
 sti_drm_update_plane(struct drm_plane *plane, struct drm_crtc *crtc,
                      struct drm_framebuffer *fb, int crtc_x, int crtc_y,
@@ -191,8 +190,7 @@ static const struct drm_plane_helper_funcs sti_drm_plane_helpers_funcs = {
         .atomic_disable = sti_drm_plane_atomic_disable,
 };
 
-static void sti_drm_plane_attach_zorder_property(struct drm_plane *plane,
-                                                 uint64_t default_val)
+static void sti_drm_plane_attach_zorder_property(struct drm_plane *plane)
 {
         struct drm_device *dev = plane->dev;
         struct sti_drm_private *private = dev->dev_private;
@@ -201,16 +199,15 @@ static void sti_drm_plane_attach_zorder_property(struct drm_plane *plane,
 
         prop = private->plane_zorder_property;
         if (!prop) {
-                prop = drm_property_create_range(dev, 0, "zpos", 0,
-                                                 GAM_MIXER_NB_DEPTH_LEVEL - 1);
+                prop = drm_property_create_range(dev, 0, "zpos", 1,
+                                                 GAM_MIXER_NB_DEPTH_LEVEL);
                 if (!prop)
                         return;
 
                 private->plane_zorder_property = prop;
         }
 
-        drm_object_attach_property(&plane->base, prop, default_val);
-        layer->zorder = default_val;
+        drm_object_attach_property(&plane->base, prop, layer->zorder);
 }
 
 struct drm_plane *sti_drm_plane_init(struct drm_device *dev,
@@ -219,7 +216,6 @@ struct drm_plane *sti_drm_plane_init(struct drm_device *dev,
                                      enum drm_plane_type type)
 {
         int err, i;
-        uint64_t default_zorder = 0;
 
         err = drm_universal_plane_init(dev, &layer->plane, possible_crtcs,
                              &sti_drm_plane_funcs,
@@ -236,15 +232,14 @@ struct drm_plane *sti_drm_plane_init(struct drm_device *dev,
                 if (sti_layer_default_zorder[i] == layer->desc)
                         break;
 
-        default_zorder = i + 1;
+        layer->zorder = i + 1;
 
         if (type == DRM_PLANE_TYPE_OVERLAY)
-                sti_drm_plane_attach_zorder_property(&layer->plane,
-                                default_zorder);
+                sti_drm_plane_attach_zorder_property(&layer->plane);
 
         DRM_DEBUG_DRIVER("drm plane:%d mapped to %s with zorder:%llu\n",
                          layer->plane.base.id,
-                         sti_layer_to_str(layer), default_zorder);
+                         sti_layer_to_str(layer), layer->zorder);
 
         return &layer->plane;
 }
diff --git a/drivers/gpu/drm/sti/sti_mixer.c b/drivers/gpu/drm/sti/sti_mixer.c
index 13a4b84deab6..61a2048cf5d6 100644
--- a/drivers/gpu/drm/sti/sti_mixer.c
+++ b/drivers/gpu/drm/sti/sti_mixer.c
@@ -103,10 +103,11 @@ static void sti_mixer_set_background_area(struct sti_mixer *mixer,
 
 int sti_mixer_set_layer_depth(struct sti_mixer *mixer, struct sti_layer *layer)
 {
-        int layer_id = 0, depth = layer->zorder;
+        int layer_id, depth = layer->zorder;
+        unsigned int i;
         u32 mask, val;
 
-        if (depth >= GAM_MIXER_NB_DEPTH_LEVEL)
+        if ((depth < 1) || (depth > GAM_MIXER_NB_DEPTH_LEVEL))
                 return 1;
 
         switch (layer->desc) {
@@ -136,15 +137,23 @@ int sti_mixer_set_layer_depth(struct sti_mixer *mixer, struct sti_layer *layer)
                 DRM_ERROR("Unknown layer %d\n", layer->desc);
                 return 1;
         }
-        mask = GAM_DEPTH_MASK_ID << (3 * depth);
-        layer_id = layer_id << (3 * depth);
+
+        /* Search if a previous depth was already assigned to the layer */
+        val = sti_mixer_reg_read(mixer, GAM_MIXER_CRB);
+        for (i = 0; i < GAM_MIXER_NB_DEPTH_LEVEL; i++) {
+                mask = GAM_DEPTH_MASK_ID << (3 * i);
+                if ((val & mask) == layer_id << (3 * i))
+                        break;
+        }
+
+        mask |= GAM_DEPTH_MASK_ID << (3 * (depth - 1));
+        layer_id = layer_id << (3 * (depth - 1));
 
         DRM_DEBUG_DRIVER("%s %s depth=%d\n", sti_mixer_to_str(mixer),
                          sti_layer_to_str(layer), depth);
         dev_dbg(mixer->dev, "GAM_MIXER_CRB val 0x%x mask 0x%x\n",
                 layer_id, mask);
 
-        val = sti_mixer_reg_read(mixer, GAM_MIXER_CRB);
         val &= ~mask;
         val |= layer_id;
         sti_mixer_reg_write(mixer, GAM_MIXER_CRB, val);
diff --git a/drivers/gpu/drm/sti/sti_mixer.h b/drivers/gpu/drm/sti/sti_mixer.h
index b97282182908..eb663f65f814 100644
--- a/drivers/gpu/drm/sti/sti_mixer.h
+++ b/drivers/gpu/drm/sti/sti_mixer.h
@@ -49,7 +49,7 @@ int sti_mixer_active_video_area(struct sti_mixer *mixer,
 void sti_mixer_set_background_status(struct sti_mixer *mixer, bool enable);
 
 /* depth in Cross-bar control = z order */
-#define GAM_MIXER_NB_DEPTH_LEVEL 7
+#define GAM_MIXER_NB_DEPTH_LEVEL 6
 
 #define STI_MIXER_MAIN 0
 #define STI_MIXER_AUX  1