drm/i915: HDCP state handling in ddi_update_pipe

The downgrade of the fullmodeset into fastset
intel_encoder->update_pipe, in possible scenario, skips the En/Dis-able
DDI. Hence breaks the HDCP state change handling.

We also don't have any hdcp tests in CI, because the shard runs don't
have hdcp capable outputs :-/

So this change fixs it by handling the HDCP state change request at
intel_encoder->update_pipe too along with enable and disable of the DDI.

Fixes: d19f958d ("drm/i915: Enable fastset for non-boot modesets.")

v2:
  Added commit id that broke the HDCP [Daniel]
Signed-off-by: Ramalingam C <ramalingam.c@intel.com>
cc: Maarten Lankhorst <maarten.lankhorst@linux.intel.com>
cc: Hans de Goede <hdegoede@redhat.com>
cc: Daniel Vetter <daniel.vetter@intel.com>
Signed-off-by: Daniel Vetter <daniel.vetter@ffwll.ch>
Link: https://patchwork.freedesktop.org/patch/msgid/1549295080-18353-1-git-send-email-ramalingam.c@intel.com

drivers/gpu/drm/i915/intel_ddi.c

@@ -3568,6 +3568,13 @@ static void intel_ddi_update_pipe(struct intel_encoder *encoder,
 {
 	if (!intel_crtc_has_type(crtc_state, INTEL_OUTPUT_HDMI))
 		intel_ddi_update_pipe_dp(encoder, crtc_state, conn_state);
+
+	if (conn_state->content_protection ==
+	    DRM_MODE_CONTENT_PROTECTION_DESIRED)
+		intel_hdcp_enable(to_intel_connector(conn_state->connector));
+	else if (conn_state->content_protection ==
+		 DRM_MODE_CONTENT_PROTECTION_UNDESIRED)
+		intel_hdcp_disable(to_intel_connector(conn_state->connector));
 }
 
 static void intel_ddi_set_fia_lane_count(struct intel_encoder *encoder,