drm/i915: Move intel_dp->prepare_link_train assignment into ddi code

It's a bit silly to go through intel_dp.c to assign the
prepare_link_train vfunc for ddi platforms when we can just
assign it directly from intel_ddi.c.
Signed-off-by: Ville Syrjälä <ville.syrjala@linux.intel.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20190604140214.9947-1-ville.syrjala@linux.intel.comReviewed-by: Manasi Navare <manasi.d.navare@intel.com>

drivers/gpu/drm/i915/intel_ddi.c

@@ -3650,7 +3650,7 @@ intel_ddi_post_pll_disable(struct intel_encoder *encoder,
 						  intel_ddi_main_link_aux_domain(dig_port));
 }
 
-void intel_ddi_prepare_link_retrain(struct intel_dp *intel_dp)
+static void intel_ddi_prepare_link_retrain(struct intel_dp *intel_dp)
 {
 	struct intel_digital_port *intel_dig_port = dp_to_dig_port(intel_dp);
 	struct drm_i915_private *dev_priv =
@@ -3958,6 +3958,9 @@ intel_ddi_init_dp_connector(struct intel_digital_port *intel_dig_port)
 		return NULL;
 
 	intel_dig_port->dp.output_reg = DDI_BUF_CTL(port);
+	intel_dig_port->dp.prepare_link_retrain =
+		intel_ddi_prepare_link_retrain;
+
 	if (!intel_dp_init_connector(intel_dig_port, connector)) {
 		kfree(connector);
 		return NULL;

drivers/gpu/drm/i915/intel_ddi.h

@@ -31,7 +31,6 @@ void intel_ddi_disable_transcoder_func(const struct intel_crtc_state *crtc_state
 void intel_ddi_enable_pipe_clock(const struct intel_crtc_state *crtc_state);
 void intel_ddi_disable_pipe_clock(const  struct intel_crtc_state *crtc_state);
 void intel_ddi_set_pipe_settings(const struct intel_crtc_state *crtc_state);
-void intel_ddi_prepare_link_retrain(struct intel_dp *intel_dp);
 bool intel_ddi_connector_get_hw_state(struct intel_connector *intel_connector);
 void intel_ddi_get_config(struct intel_encoder *encoder,
 			  struct intel_crtc_state *pipe_config);

drivers/gpu/drm/i915/intel_dp.c

@@ -7349,10 +7349,6 @@ intel_dp_init_connector(struct intel_digital_port *intel_dig_port,
 	intel_dp->pps_pipe = INVALID_PIPE;
 	intel_dp->active_pipe = INVALID_PIPE;
 
-	/* intel_dp vfuncs */
-	if (HAS_DDI(dev_priv))
-		intel_dp->prepare_link_retrain = intel_ddi_prepare_link_retrain;
-
 	/* Preserve the current hw state. */
 	intel_dp->DP = I915_READ(intel_dp->output_reg);
 	intel_dp->attached_connector = intel_connector;