drm/sun4i: return only planes for layers created

As we are going to add support for the Allwinner DE2 Mixer in sun4i-drm
driver, we will finally have two types of layers.

Each layer is bound to a drm_plane that is CRTC-specific, so we create
them when initializing CRTC (calling sun4i_layers_init, which will be
generalized in next patch). The drm_plane's will be used when creating
CRTC, but the CRTC initialization code do not care other properties of
the layer, so we let the sun4i_layers_init function return drm_plane's
only.

As we have no need to trace the layers after the CRTC is properly
created, we drop the layers pointer in sun4i_crtc struct.

Doing this uncouples the CRTC code from the type of layer (the
sun4i_layers_init function name is still hardcoded and will be changed
in the next patch), so that we can finally gain support for the
mixer in DE2, which has different layers.
Signed-off-by: Icenowy Zheng <icenowy@aosc.io>
Reviewed-by: Chen-Yu Tsai <wens@csie.org>
Signed-off-by: Maxime Ripard <maxime.ripard@free-electrons.com>

drivers/gpu/drm/sun4i/sun4i_crtc.c

@@ -139,6 +139,7 @@ struct sun4i_crtc *sun4i_crtc_init(struct drm_device *drm,
 				   struct sun4i_tcon *tcon)
 {
 	struct sun4i_crtc *scrtc;
+	struct drm_plane **planes;
 	struct drm_plane *primary = NULL, *cursor = NULL;
 	int ret, i;
 
@@ -149,22 +150,22 @@ struct sun4i_crtc *sun4i_crtc_init(struct drm_device *drm,
 	scrtc->tcon = tcon;
 
 	/* Create our layers */
-	scrtc->layers = sun4i_layers_init(drm, scrtc->backend);
-	if (IS_ERR(scrtc->layers)) {
+	planes = sun4i_layers_init(drm, scrtc);
+	if (IS_ERR(planes)) {
 		dev_err(drm->dev, "Couldn't create the planes\n");
 		return NULL;
 	}
 
 	/* find primary and cursor planes for drm_crtc_init_with_planes */
-	for (i = 0; scrtc->layers[i]; i++) {
-		struct sun4i_layer *layer = scrtc->layers[i];
+	for (i = 0; planes[i]; i++) {
+		struct drm_plane *plane = planes[i];
 
-		switch (layer->plane.type) {
+		switch (plane->type) {
 		case DRM_PLANE_TYPE_PRIMARY:
-			primary = &layer->plane;
+			primary = plane;
 			break;
 		case DRM_PLANE_TYPE_CURSOR:
-			cursor = &layer->plane;
+			cursor = plane;
 			break;
 		default:
 			break;
@@ -188,12 +189,12 @@ struct sun4i_crtc *sun4i_crtc_init(struct drm_device *drm,
 						   1);
 
 	/* Set possible_crtcs to this crtc for overlay planes */
-	for (i = 0; scrtc->layers[i]; i++) {
+	for (i = 0; planes[i]; i++) {
 		uint32_t possible_crtcs = BIT(drm_crtc_index(&scrtc->crtc));
-		struct sun4i_layer *layer = scrtc->layers[i];
+		struct drm_plane *plane = planes[i];
 
-		if (layer->plane.type == DRM_PLANE_TYPE_OVERLAY)
-			layer->plane.possible_crtcs = possible_crtcs;
+		if (plane->type == DRM_PLANE_TYPE_OVERLAY)
+			plane->possible_crtcs = possible_crtcs;
 	}
 
 	return scrtc;

drivers/gpu/drm/sun4i/sun4i_crtc.h

@@ -19,7 +19,6 @@ struct sun4i_crtc {
 
 	struct sun4i_backend		*backend;
 	struct sun4i_tcon		*tcon;
-	struct sun4i_layer		**layers;
 };
 
 static inline struct sun4i_crtc *drm_crtc_to_sun4i_crtc(struct drm_crtc *crtc)

drivers/gpu/drm/sun4i/sun4i_layer.c

@@ -16,6 +16,7 @@
 #include <drm/drmP.h>
 
 #include "sun4i_backend.h"
+#include "sun4i_crtc.h"
 #include "sun4i_layer.h"
 
 struct sun4i_plane_desc {
@@ -128,15 +129,16 @@ static struct sun4i_layer *sun4i_layer_init_one(struct drm_device *drm,
 	return layer;
 }
 
-struct sun4i_layer **sun4i_layers_init(struct drm_device *drm,
-				       struct sun4i_backend *backend)
+struct drm_plane **sun4i_layers_init(struct drm_device *drm,
+				     struct sun4i_crtc *crtc)
 {
-	struct sun4i_layer **layers;
+	struct drm_plane **planes;
+	struct sun4i_backend *backend = crtc->backend;
 	int i;
 
-	layers = devm_kcalloc(drm->dev, ARRAY_SIZE(sun4i_backend_planes) + 1,
-			      sizeof(*layers), GFP_KERNEL);
-	if (!layers)
+	planes = devm_kcalloc(drm->dev, ARRAY_SIZE(sun4i_backend_planes) + 1,
+			      sizeof(*planes), GFP_KERNEL);
+	if (!planes)
 		return ERR_PTR(-ENOMEM);
 
 	/*
@@ -178,8 +180,8 @@ struct sun4i_layer **sun4i_layers_init(struct drm_device *drm,
 				   SUN4I_BACKEND_ATTCTL_REG0_LAY_PIPESEL(plane->pipe));
 
 		layer->id = i;
-		layers[i] = layer;
+		planes[i] = &layer->plane;
 	};
 
-	return layers;
+	return planes;
 }

drivers/gpu/drm/sun4i/sun4i_layer.h

@@ -26,7 +26,7 @@ plane_to_sun4i_layer(struct drm_plane *plane)
 	return container_of(plane, struct sun4i_layer, plane);
 }
 
-struct sun4i_layer **sun4i_layers_init(struct drm_device *drm,
-				       struct sun4i_backend *backend);
+struct drm_plane **sun4i_layers_init(struct drm_device *drm,
+				     struct sun4i_crtc *crtc);
 
 #endif /* _SUN4I_LAYER_H_ */