drm/i915/dp: Preparation for DP phy compliance auto test

During DP phy compliance auto test mode, sink will request
combination of different test pattern with differnt level of
vswing, pre-emphasis. Function added to prepare for it.
Reviewed-by: NManasi Navare <manasi.d.navare@intel.com>
Signed-off-by: NAnimesh Manna <animesh.manna@intel.com>
Signed-off-by: NMaarten Lankhorst <maarten.lankhorst@linux.intel.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20200316103759.12867-5-animesh.manna@intel.com

drivers/gpu/drm/i915/display/intel_display_types.h

@@ -1238,6 +1238,7 @@ struct intel_dp_compliance_data {
 	u8 video_pattern;
 	u16 hdisplay, vdisplay;
 	u8 bpc;
+	struct drm_dp_phy_test_params phytest;
 };
 
 struct intel_dp_compliance {

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

@@ -5001,9 +5001,33 @@ static u8 intel_dp_autotest_edid(struct intel_dp *intel_dp)
 	return test_result;
 }
 
+static u8 intel_dp_prepare_phytest(struct intel_dp *intel_dp)
+{
+	struct drm_dp_phy_test_params *data =
+		&intel_dp->compliance.test_data.phytest;
+
+	if (drm_dp_get_phy_test_pattern(&intel_dp->aux, data)) {
+		DRM_DEBUG_KMS("DP Phy Test pattern AUX read failure\n");
+		return DP_TEST_NAK;
+	}
+
+	/*
+	 * link_mst is set to false to avoid executing mst related code
+	 * during compliance testing.
+	 */
+	intel_dp->link_mst = false;
+
+	return DP_TEST_ACK;
+}
+
 static u8 intel_dp_autotest_phy_pattern(struct intel_dp *intel_dp)
 {
 	u8 test_result = DP_TEST_NAK;
+
+	test_result = intel_dp_prepare_phytest(intel_dp);
+	if (test_result != DP_TEST_ACK)
+		DRM_ERROR("Phy test preparation failed\n");
+
 	return test_result;
 }