drm: Add drm_universal_plane_init()

Add a new plane initialization interface for universal plane support
that allows a specific plane type (primary, cursor, or overlay) to
be specified.

drm_plane_init() remains as a compatibility API to reduce churn in
existing drivers.  The 'bool priv' parameter has been changed to
'bool is_primary' under the assumption that all existing uses of
private planes were representing primary planes.
Signed-off-by: Matt Roper <matthew.d.roper@intel.com>
Reviewed-by: Rob Clark <robdclark@gmail.com>

drivers/gpu/drm/drm_crtc.c

@@ -1000,26 +1000,25 @@ void drm_encoder_cleanup(struct drm_encoder *encoder)
 EXPORT_SYMBOL(drm_encoder_cleanup);
 
 /**
- * drm_plane_init - Initialise a new plane object
+ * drm_universal_plane_init - Initialize a new universal plane object
  * @dev: DRM device
  * @plane: plane object to init
  * @possible_crtcs: bitmask of possible CRTCs
  * @funcs: callbacks for the new plane
  * @formats: array of supported formats (%DRM_FORMAT_*)
  * @format_count: number of elements in @formats
- * @priv: plane is private (hidden from userspace)?
+ * @type: type of plane (overlay, primary, cursor)
  *
- * Inits a preallocate plane object created as base part of a driver plane
- * object.
+ * Initializes a plane object of type @type.
  *
  * Returns:
  * Zero on success, error code on failure.
  */
-int drm_plane_init(struct drm_device *dev, struct drm_plane *plane,
+int drm_universal_plane_init(struct drm_device *dev, struct drm_plane *plane,
 			     unsigned long possible_crtcs,
 			     const struct drm_plane_funcs *funcs,
 			     const uint32_t *formats, uint32_t format_count,
-		   bool priv)
+			     enum drm_plane_type type)
 {
 	int ret;
 
@@ -1044,26 +1043,49 @@ int drm_plane_init(struct drm_device *dev, struct drm_plane *plane,
 	memcpy(plane->format_types, formats, format_count * sizeof(uint32_t));
 	plane->format_count = format_count;
 	plane->possible_crtcs = possible_crtcs;
-	plane->type = DRM_PLANE_TYPE_OVERLAY;
+	plane->type = type;
 
-	/* private planes are not exposed to userspace, but depending on
-	 * display hardware, might be convenient to allow sharing programming
-	 * for the scanout engine with the crtc implementation.
-	 */
-	if (!priv) {
 	list_add_tail(&plane->head, &dev->mode_config.plane_list);
 	dev->mode_config.num_total_plane++;
 	if (plane->type == DRM_PLANE_TYPE_OVERLAY)
 		dev->mode_config.num_overlay_plane++;
-	} else {
-		INIT_LIST_HEAD(&plane->head);
-	}
 
  out:
 	drm_modeset_unlock_all(dev);
 
 	return ret;
 }
+EXPORT_SYMBOL(drm_universal_plane_init);
+
+/**
+ * drm_plane_init - Initialize a legacy plane
+ * @dev: DRM device
+ * @plane: plane object to init
+ * @possible_crtcs: bitmask of possible CRTCs
+ * @funcs: callbacks for the new plane
+ * @formats: array of supported formats (%DRM_FORMAT_*)
+ * @format_count: number of elements in @formats
+ * @is_primary: plane type (primary vs overlay)
+ *
+ * Legacy API to initialize a DRM plane.
+ *
+ * New drivers should call drm_universal_plane_init() instead.
+ *
+ * Returns:
+ * Zero on success, error code on failure.
+ */
+int drm_plane_init(struct drm_device *dev, struct drm_plane *plane,
+		   unsigned long possible_crtcs,
+		   const struct drm_plane_funcs *funcs,
+		   const uint32_t *formats, uint32_t format_count,
+		   bool is_primary)
+{
+	enum drm_plane_type type;
+
+	type = is_primary ? DRM_PLANE_TYPE_PRIMARY : DRM_PLANE_TYPE_OVERLAY;
+	return drm_universal_plane_init(dev, plane, possible_crtcs, funcs,
+					formats, format_count, type);
+}
 EXPORT_SYMBOL(drm_plane_init);
 
 /**
@@ -1081,13 +1103,13 @@ void drm_plane_cleanup(struct drm_plane *plane)
 	drm_modeset_lock_all(dev);
 	kfree(plane->format_types);
 	drm_mode_object_put(dev, &plane->base);
-	/* if not added to a list, it must be a private plane */
-	if (!list_empty(&plane->head)) {
+
+	BUG_ON(list_empty(&plane->head));
+
 	list_del(&plane->head);
 	dev->mode_config.num_total_plane--;
 	if (plane->type == DRM_PLANE_TYPE_OVERLAY)
 		dev->mode_config.num_overlay_plane--;
-	}
 	drm_modeset_unlock_all(dev);
 }
 EXPORT_SYMBOL(drm_plane_cleanup);

include/drm/drm_crtc.h

@@ -874,12 +874,19 @@ static inline bool drm_encoder_crtc_ok(struct drm_encoder *encoder,
 	return !!(encoder->possible_crtcs & drm_crtc_mask(crtc));
 }
 
+extern int drm_universal_plane_init(struct drm_device *dev,
+				    struct drm_plane *plane,
+				    unsigned long possible_crtcs,
+				    const struct drm_plane_funcs *funcs,
+				    const uint32_t *formats,
+				    uint32_t format_count,
+				    enum drm_plane_type type);
 extern int drm_plane_init(struct drm_device *dev,
 			  struct drm_plane *plane,
 			  unsigned long possible_crtcs,
 			  const struct drm_plane_funcs *funcs,
 			  const uint32_t *formats, uint32_t format_count,
-			  bool priv);
+			  bool is_primary);
 extern void drm_plane_cleanup(struct drm_plane *plane);
 extern void drm_plane_force_disable(struct drm_plane *plane);
 extern int drm_crtc_check_viewport(const struct drm_crtc *crtc,