drm/atomic: Extract needs_modeset function

We use the same check already in the atomic core, so might as well
make this official. And it's also reused in e.g. i915.

Motivated by Maarten's idea to extract a connector_changed state out
of mode_changed.

Cc: Maarten Lankhorst <maarten.lankhorst@linux.intel.com>
Reviewed-By: Maarten Lankhorst <maarten.lankhorst@linux.intel.com>
Signed-off-by: Daniel Vetter <daniel.vetter@intel.com>
diff --git a/drivers/gpu/drm/drm_atomic_helper.c b/drivers/gpu/drm/drm_atomic_helper.c
index 536ae4d..b06a607 100644
--- a/drivers/gpu/drm/drm_atomic_helper.c
+++ b/drivers/gpu/drm/drm_atomic_helper.c
@@ -331,12 +331,6 @@
 	return 0;
 }
 
-static bool
-needs_modeset(struct drm_crtc_state *state)
-{
-	return state->mode_changed || state->active_changed;
-}
-
 /**
  * drm_atomic_helper_check_modeset - validate state object for modeset changes
  * @dev: DRM device
@@ -414,7 +408,7 @@
 			crtc_state->active_changed = true;
 		}
 
-		if (!needs_modeset(crtc_state))
+		if (!drm_atomic_crtc_needs_modeset(crtc_state))
 			continue;
 
 		DRM_DEBUG_ATOMIC("[CRTC:%d] needs all connectors, enable: %c, active: %c\n",
@@ -564,7 +558,7 @@
 		old_crtc_state = old_state->crtc_states[drm_crtc_index(old_conn_state->crtc)];
 
 		if (!old_crtc_state->active ||
-		    !needs_modeset(old_conn_state->crtc->state))
+		    !drm_atomic_crtc_needs_modeset(old_conn_state->crtc->state))
 			continue;
 
 		encoder = old_conn_state->best_encoder;
@@ -601,7 +595,7 @@
 		const struct drm_crtc_helper_funcs *funcs;
 
 		/* Shut down everything that needs a full modeset. */
-		if (!needs_modeset(crtc->state))
+		if (!drm_atomic_crtc_needs_modeset(crtc->state))
 			continue;
 
 		if (!old_crtc_state->active)
@@ -792,7 +786,7 @@
 		const struct drm_crtc_helper_funcs *funcs;
 
 		/* Need to filter out CRTCs where only planes change. */
-		if (!needs_modeset(crtc->state))
+		if (!drm_atomic_crtc_needs_modeset(crtc->state))
 			continue;
 
 		if (!crtc->state->active)
@@ -819,7 +813,7 @@
 			continue;
 
 		if (!connector->state->crtc->state->active ||
-		    !needs_modeset(connector->state->crtc->state))
+		    !drm_atomic_crtc_needs_modeset(connector->state->crtc->state))
 			continue;
 
 		encoder = connector->state->best_encoder;