drm/bridge: dw-hdmi: Use drm_atomic_helper_best_encoder()

We have a 1:1 relationship between connectors and encoders, which means
we can rely on the drm_atomic_helper_best_encoder() behavior.

We still have to explicitly assign ->best_encoder() to
drm_atomic_helper_best_encoder(), because the automated fallback to
drm_atomic_helper_best_encoder() when ->best_encoder() is NULL is only
available when the DRM device is using the atomic helpers, and this bridge
is compatible with non-atomic and atomic devices.

Signed-off-by: Boris Brezillon <boris.brezillon@free-electrons.com>
Signed-off-by: Daniel Vetter <daniel.vetter@ffwll.ch>
Link: http://patchwork.freedesktop.org/patch/msgid/1465300095-16971-21-git-send-email-boris.brezillon@free-electrons.com

drivers/gpu/drm/bridge/dw-hdmi.c

@@ -1476,15 +1476,6 @@ dw_hdmi_connector_mode_valid(struct drm_connector *connector,
 	return mode_status;
 }
 
-static struct drm_encoder *dw_hdmi_connector_best_encoder(struct drm_connector
-							   *connector)
-{
-	struct dw_hdmi *hdmi = container_of(connector, struct dw_hdmi,
-					     connector);
-
-	return hdmi->encoder;
-}
-
 static void dw_hdmi_connector_destroy(struct drm_connector *connector)
 {
 	drm_connector_unregister(connector);
@@ -1525,7 +1516,7 @@ static const struct drm_connector_funcs dw_hdmi_atomic_connector_funcs = {
 static const struct drm_connector_helper_funcs dw_hdmi_connector_helper_funcs = {
 	.get_modes = dw_hdmi_connector_get_modes,
 	.mode_valid = dw_hdmi_connector_mode_valid,
-	.best_encoder = dw_hdmi_connector_best_encoder,
+	.best_encoder = drm_atomic_helper_best_encoder,
 };
 
 static const struct drm_bridge_funcs dw_hdmi_bridge_funcs = {