drm/tegra: dc: Use base atomic state helpers

Instead of duplicating the code, make use of the newly introduced atomic
state duplicate and destroy helpers. This allows changes to the base
atomic state handling to automatically propagate to the Tegra driver and
thereby prevent breakage resulting from both copies going out of sync.
Signed-off-by: Thierry Reding <treding@nvidia.com>

drivers/gpu/drm/tegra/dc.c

@@ -425,8 +425,8 @@ static void tegra_plane_reset(struct drm_plane *plane)
 {
 	struct tegra_plane_state *state;
 
-	if (plane->state && plane->state->fb)
-		drm_framebuffer_unreference(plane->state->fb);
+	if (plane->state)
+		__drm_atomic_helper_plane_destroy_state(plane, plane->state);
 
 	kfree(plane->state);
 	plane->state = NULL;
@@ -443,12 +443,14 @@ static struct drm_plane_state *tegra_plane_atomic_duplicate_state(struct drm_pla
 	struct tegra_plane_state *state = to_tegra_plane_state(plane->state);
 	struct tegra_plane_state *copy;
 
-	copy = kmemdup(state, sizeof(*state), GFP_KERNEL);
+	copy = kmalloc(sizeof(*copy), GFP_KERNEL);
 	if (!copy)
 		return NULL;
 
-	if (copy->base.fb)
-		drm_framebuffer_reference(copy->base.fb);
+	__drm_atomic_helper_plane_duplicate_state(plane, &copy->base);
+	copy->tiling = state->tiling;
+	copy->format = state->format;
+	copy->swap = state->swap;
 
 	return &copy->base;
 }
@@ -456,9 +458,7 @@ static struct drm_plane_state *tegra_plane_atomic_duplicate_state(struct drm_pla
 static void tegra_plane_atomic_destroy_state(struct drm_plane *plane,
 					     struct drm_plane_state *state)
 {
-	if (state->fb)
-		drm_framebuffer_unreference(state->fb);
-
+	__drm_atomic_helper_plane_destroy_state(plane, state);
 	kfree(state);
 }
 
@@ -1002,6 +1002,9 @@ static void tegra_crtc_reset(struct drm_crtc *crtc)
 {
 	struct tegra_dc_state *state;
 
+	if (crtc->state)
+		__drm_atomic_helper_crtc_destroy_state(crtc, crtc->state);
+
 	kfree(crtc->state);
 	crtc->state = NULL;
 
@@ -1018,14 +1021,15 @@ tegra_crtc_atomic_duplicate_state(struct drm_crtc *crtc)
 	struct tegra_dc_state *state = to_dc_state(crtc->state);
 	struct tegra_dc_state *copy;
 
-	copy = kmemdup(state, sizeof(*state), GFP_KERNEL);
+	copy = kmalloc(sizeof(*copy), GFP_KERNEL);
 	if (!copy)
 		return NULL;
 
-	copy->base.mode_changed = false;
-	copy->base.active_changed = false;
-	copy->base.planes_changed = false;
-	copy->base.event = NULL;
+	__drm_atomic_helper_crtc_duplicate_state(crtc, &copy->base);
+	copy->clk = state->clk;
+	copy->pclk = state->pclk;
+	copy->div = state->div;
+	copy->planes = state->planes;
 
 	return &copy->base;
 }
@@ -1033,6 +1037,7 @@ tegra_crtc_atomic_duplicate_state(struct drm_crtc *crtc)
 static void tegra_crtc_atomic_destroy_state(struct drm_crtc *crtc,
 					    struct drm_crtc_state *state)
 {
+	__drm_atomic_helper_crtc_destroy_state(crtc, state);
 	kfree(state);
 }