drm: Add checks for atomic_[duplicate/destroy]_state with atomic drivers

This patch add checks for atomic_[duplicate/destroy]_state of
drm_[connector/crtc/plane]_funcs for atomic drivers in the relevant
drm_*_init functions since these callback are mandatory for atomic drivers.

Update the kerneldoc comments for those callbacks.
Signed-off-by: Haneen Mohammed <hamohammed.sa@gmail.com>
Reviewed-by: Sean Paul <seanpaul@chromium.org>
Signed-off-by: Daniel Vetter <daniel.vetter@ffwll.ch>
Link: https://patchwork.freedesktop.org/patch/msgid/20180525012555.GA8448@haneen-vb

drivers/gpu/drm/drm_connector.c

@@ -195,6 +195,10 @@ int drm_connector_init(struct drm_device *dev,
 	struct ida *connector_ida =
 		&drm_connector_enum_list[connector_type].ida;
 
+	WARN_ON(drm_drv_uses_atomic_modeset(dev) &&
+		(!funcs->atomic_destroy_state ||
+		 !funcs->atomic_duplicate_state));
+
 	ret = __drm_mode_object_add(dev, &connector->base,
 				    DRM_MODE_OBJECT_CONNECTOR,
 				    false, drm_connector_free);

drivers/gpu/drm/drm_crtc.c

@@ -286,6 +286,10 @@ int drm_crtc_init_with_planes(struct drm_device *dev, struct drm_crtc *crtc,
 	if (WARN_ON(config->num_crtc >= 32))
 		return -EINVAL;
 
+	WARN_ON(drm_drv_uses_atomic_modeset(dev) &&
+		(!funcs->atomic_destroy_state ||
+		 !funcs->atomic_duplicate_state));
+
 	crtc->dev = dev;
 	crtc->funcs = funcs;
 

drivers/gpu/drm/drm_plane.c

@@ -177,6 +177,10 @@ int drm_universal_plane_init(struct drm_device *dev, struct drm_plane *plane,
 	if (WARN_ON(config->num_total_plane >= 32))
 		return -EINVAL;
 
+	WARN_ON(drm_drv_uses_atomic_modeset(dev) &&
+		(!funcs->atomic_destroy_state ||
+		 !funcs->atomic_duplicate_state));
+
 	ret = drm_mode_object_add(dev, &plane->base, DRM_MODE_OBJECT_PLANE);
 	if (ret)
 		return ret;

include/drm/drm_connector.h

@@ -616,6 +616,8 @@ struct drm_connector_funcs {
 	 * cleaned up by calling the @atomic_destroy_state hook in this
 	 * structure.
 	 *
+	 * This callback is mandatory for atomic drivers.
+	 *
 	 * Atomic drivers which don't subclass &struct drm_connector_state should use
 	 * drm_atomic_helper_connector_duplicate_state(). Drivers that subclass the
 	 * state structure to extend it with driver-private state should use
@@ -642,6 +644,8 @@ struct drm_connector_funcs {
 	 *
 	 * Destroy a state duplicated with @atomic_duplicate_state and release
 	 * or unreference all resources it references
+	 *
+	 * This callback is mandatory for atomic drivers.
 	 */
 	void (*atomic_destroy_state)(struct drm_connector *connector,
 				     struct drm_connector_state *state);

include/drm/drm_crtc.h

@@ -506,6 +506,8 @@ struct drm_crtc_funcs {
 	 * cleaned up by calling the @atomic_destroy_state hook in this
 	 * structure.
 	 *
+	 * This callback is mandatory for atomic drivers.
+	 *
 	 * Atomic drivers which don't subclass &struct drm_crtc_state should use
 	 * drm_atomic_helper_crtc_duplicate_state(). Drivers that subclass the
 	 * state structure to extend it with driver-private state should use
@@ -532,6 +534,8 @@ struct drm_crtc_funcs {
 	 *
 	 * Destroy a state duplicated with @atomic_duplicate_state and release
 	 * or unreference all resources it references
+	 *
+	 * This callback is mandatory for atomic drivers.
 	 */
 	void (*atomic_destroy_state)(struct drm_crtc *crtc,
 				     struct drm_crtc_state *state);

include/drm/drm_plane.h

@@ -288,6 +288,8 @@ struct drm_plane_funcs {
 	 * cleaned up by calling the @atomic_destroy_state hook in this
 	 * structure.
 	 *
+	 * This callback is mandatory for atomic drivers.
+	 *
 	 * Atomic drivers which don't subclass &struct drm_plane_state should use
 	 * drm_atomic_helper_plane_duplicate_state(). Drivers that subclass the
 	 * state structure to extend it with driver-private state should use
@@ -314,6 +316,8 @@ struct drm_plane_funcs {
 	 *
 	 * Destroy a state duplicated with @atomic_duplicate_state and release
 	 * or unreference all resources it references
+	 *
+	 * This callback is mandatory for atomic drivers.
 	 */
 	void (*atomic_destroy_state)(struct drm_plane *plane,
 				     struct drm_plane_state *state);