drm/ast: Enable primary plane with CRTC

As the CRTC requires a primary plane for display, ensure that the
primary plane is enabled with the CRTC.

Use drm_atomic_helper_check_crtc_state(). Add all affected planes
to the atomic state so that their state will be checked as well.
Signed-off-by: Thomas Zimmermann <tzimmermann@suse.de>
Acked-by: Jocelyn Falempe <jfalempe@redhat.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20220617103226.25617-4-tzimmermann@suse.de

drivers/gpu/drm/ast/ast_mode.c

@@ -1108,15 +1108,19 @@ ast_crtc_helper_mode_valid(struct drm_crtc *crtc, const struct drm_display_mode
 static int ast_crtc_helper_atomic_check(struct drm_crtc *crtc,
 					struct drm_atomic_state *state)
 {
-	struct drm_crtc_state *crtc_state = drm_atomic_get_new_crtc_state(state,
-									  crtc);
+	struct drm_crtc_state *crtc_state = drm_atomic_get_new_crtc_state(state, crtc);
 	struct drm_device *dev = crtc->dev;
 	struct ast_crtc_state *ast_state;
 	const struct drm_format_info *format;
 	bool succ;
+	int ret;
+
+	ret = drm_atomic_helper_check_crtc_state(crtc_state, false);
+	if (ret)
+		return ret;
 
 	if (!crtc_state->enable)
-		return 0; /* no mode checks if CRTC is being disabled */
+		goto out;
 
 	ast_state = to_ast_crtc_state(crtc_state);
 
@@ -1130,7 +1134,8 @@ static int ast_crtc_helper_atomic_check(struct drm_crtc *crtc,
 	if (!succ)
 		return -EINVAL;
 
-	return 0;
+out:
+	return drm_atomic_add_affected_planes(state, crtc);
 }
 
 static void ast_crtc_helper_atomic_begin(struct drm_crtc *crtc, struct drm_atomic_state *state)