drm/i915: HDCP: fix Ri prime check done during link check

The check was always succeeding even in case of a mismatch due to the
HDCP_STATUS_ENC bit being set. Make sure both bits are actually set.
Signed-off-by: Oliver Barta <oliver.barta@aptiv.com>
Fixes: 2320175f ("drm/i915: Implement HDCP for HDMI")
Reviewed-by: Ramalingam C <ramalingam.c@intel.com>
Signed-off-by: Jani Nikula <jani.nikula@intel.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20200328104100.12162-1-oliver.barta@aptiv.com
(cherry picked from commit 3ffaf56e)
Signed-off-by: Rodrigo Vivi <rodrigo.vivi@intel.com>

drivers/gpu/drm/i915/display/intel_hdmi.c

@@ -1536,7 +1536,8 @@ bool intel_hdmi_hdcp_check_link(struct intel_digital_port *intel_dig_port)
 	intel_de_write(i915, HDCP_RPRIME(i915, cpu_transcoder, port), ri.reg);
 
 	/* Wait for Ri prime match */
-	if (wait_for(intel_de_read(i915, HDCP_STATUS(i915, cpu_transcoder, port)) &
+	if (wait_for((intel_de_read(i915, HDCP_STATUS(i915, cpu_transcoder, port)) &
+		      (HDCP_STATUS_RI_MATCH | HDCP_STATUS_ENC)) ==
 		     (HDCP_STATUS_RI_MATCH | HDCP_STATUS_ENC), 1)) {
 		DRM_ERROR("Ri' mismatch detected, link check failed (%x)\n",
 			  intel_de_read(i915, HDCP_STATUS(i915, cpu_transcoder, port)));