1 files changed, 34 insertions, 15 deletions

diff --git a/drivers/gpu/drm/drm_atomic_helper.c b/drivers/gpu/drm/drm_atomic_helper.c
index 997fd21e5388..43a0b3dfa846 100644
--- a/drivers/gpu/drm/drm_atomic_helper.c
+++ b/drivers/gpu/drm/drm_atomic_helper.c
@@ -384,8 +384,6 @@ mode_fixup(struct drm_atomic_state *state)
                  */
                 encoder = conn_state->best_encoder;
                 funcs = encoder->helper_private;
-                if (!funcs)
-                        continue;
 
                 ret = drm_bridge_mode_fixup(encoder->bridge, &crtc_state->mode,
                                 &crtc_state->adjusted_mode);
@@ -394,7 +392,7 @@ mode_fixup(struct drm_atomic_state *state)
                         return -EINVAL;
                 }
 
-                if (funcs->atomic_check) {
+                if (funcs && funcs->atomic_check) {
                         ret = funcs->atomic_check(encoder, crtc_state,
                                                   conn_state);
                         if (ret) {
@@ -402,7 +400,7 @@ mode_fixup(struct drm_atomic_state *state)
                                                  encoder->base.id, encoder->name);
                                 return ret;
                         }
-                } else if (funcs->mode_fixup) {
+                } else if (funcs && funcs->mode_fixup) {
                         ret = funcs->mode_fixup(encoder, &crtc_state->mode,
                                                 &crtc_state->adjusted_mode);
                         if (!ret) {
@@ -707,12 +705,14 @@ disable_outputs(struct drm_device *dev, struct drm_atomic_state *old_state)
                 drm_bridge_disable(encoder->bridge);
 
                 /* Right function depends upon target state. */
-                if (connector->state->crtc && funcs->prepare)
-                        funcs->prepare(encoder);
-                else if (funcs->disable)
-                        funcs->disable(encoder);
-                else
-                        funcs->dpms(encoder, DRM_MODE_DPMS_OFF);
+                if (funcs) {
+                        if (connector->state->crtc && funcs->prepare)
+                                funcs->prepare(encoder);
+                        else if (funcs->disable)
+                                funcs->disable(encoder);
+                        else if (funcs->dpms)
+                                funcs->dpms(encoder, DRM_MODE_DPMS_OFF);
+                }
 
                 drm_bridge_post_disable(encoder->bridge);
         }
@@ -873,7 +873,7 @@ crtc_set_mode(struct drm_device *dev, struct drm_atomic_state *old_state)
                  * Each encoder has at most one connector (since we always steal
                  * it away), so we won't call mode_set hooks twice.
                  */
-                if (funcs->mode_set)
+                if (funcs && funcs->mode_set)
                         funcs->mode_set(encoder, mode, adjusted_mode);
 
                 drm_bridge_mode_set(encoder->bridge, mode, adjusted_mode);
@@ -974,10 +974,12 @@ void drm_atomic_helper_commit_modeset_enables(struct drm_device *dev,
                  */
                 drm_bridge_pre_enable(encoder->bridge);
 
-                if (funcs->enable)
-                        funcs->enable(encoder);
-                else
-                        funcs->commit(encoder);
+                if (funcs) {
+                        if (funcs->enable)
+                                funcs->enable(encoder);
+                        else if (funcs->commit)
+                                funcs->commit(encoder);
+                }
 
                 drm_bridge_enable(encoder->bridge);
         }
@@ -2481,6 +2483,23 @@ backoff:
 EXPORT_SYMBOL(drm_atomic_helper_connector_dpms);
 
 /**
+ * drm_atomic_helper_best_encoder - Helper for &drm_connector_helper_funcs
+ *                                  ->best_encoder callback
+ * @connector: Connector control structure
+ *
+ * This is a &drm_connector_helper_funcs ->best_encoder callback helper for
+ * connectors that support exactly 1 encoder, statically determined at driver
+ * init time.
+ */
+struct drm_encoder *
+drm_atomic_helper_best_encoder(struct drm_connector *connector)
+{
+        WARN_ON(connector->encoder_ids[1]);
+        return drm_encoder_find(connector->dev, connector->encoder_ids[0]);
+}
+EXPORT_SYMBOL(drm_atomic_helper_best_encoder);
+
+/**
  * DOC: atomic state reset and initialization
  *
  * Both the drm core and the atomic helpers assume that there is always the full