drm/i915: check for audio and infoframe changes across mode sets v2

If these change (e.g. after a modeset following a fastboot), we need to
do a full mode set.

v2:
  - put under pipe_config check so we don't deref a null state (Jesse)

Signed-off-by: Jesse Barnes <jbarnes@virtuousgeek.org>
Reviewed-by: Ander Conselvan de Oliveira <ander.conselvan.de.oliveira@intel.com>
Signed-off-by: Daniel Vetter <daniel.vetter@ffwll.ch>

drivers/gpu/drm/i915/intel_display.c

@@ -11325,8 +11325,18 @@ static int intel_crtc_set_config(struct drm_mode_set *set)
 						   &modeset_pipes,
 						   &prepare_pipes,
 						   &disable_pipes);
-	if (IS_ERR(pipe_config))
+	if (IS_ERR(pipe_config)) {
 		goto fail;
+	} else if (pipe_config) {
+		if (to_intel_crtc(set->crtc)->new_config->has_audio !=
+		    to_intel_crtc(set->crtc)->config.has_audio)
+			config->mode_changed = true;
+
+		/* Force mode sets for any infoframe stuff */
+		if (to_intel_crtc(set->crtc)->new_config->has_infoframe ||
+		    to_intel_crtc(set->crtc)->config.has_infoframe)
+			config->mode_changed = true;
+	}
 
 	/* set_mode will free it in the mode_changed case */
 	if (!config->mode_changed)