drm/radeon: fix dig encoder selection on DCE61

Was using the DCE41 code which was wrong. Fixes
blank displays on a number of Trinity systems.
Signed-off-by: Alex Deucher <alexander.deucher@amd.com>
Cc: stable@vger.kernel.org

drivers/gpu/drm/radeon/atombios_encoders.c

@@ -1769,13 +1769,34 @@ static int radeon_atom_pick_dig_encoder(struct drm_encoder *encoder)
 	struct radeon_crtc *radeon_crtc = to_radeon_crtc(encoder->crtc);
 	struct radeon_encoder *radeon_encoder = to_radeon_encoder(encoder);
 	struct drm_encoder *test_encoder;
-	struct radeon_encoder_atom_dig *dig;
+	struct radeon_encoder_atom_dig *dig = radeon_encoder->enc_priv;
 	uint32_t dig_enc_in_use = 0;
 
+	if (ASIC_IS_DCE6(rdev)) {
+		/* DCE6 */
+		switch (radeon_encoder->encoder_id) {
+		case ENCODER_OBJECT_ID_INTERNAL_UNIPHY:
+			if (dig->linkb)
+				return 1;
+			else
+				return 0;
+			break;
+		case ENCODER_OBJECT_ID_INTERNAL_UNIPHY1:
+			if (dig->linkb)
+				return 3;
+			else
+				return 2;
+			break;
+		case ENCODER_OBJECT_ID_INTERNAL_UNIPHY2:
+			if (dig->linkb)
+				return 5;
+			else
+				return 4;
+			break;
+		}
+	} else if (ASIC_IS_DCE4(rdev)) {
 		/* DCE4/5 */
-	if (ASIC_IS_DCE4(rdev)) {
-		dig = radeon_encoder->enc_priv;
-		if (ASIC_IS_DCE41(rdev)) {
+		if (ASIC_IS_DCE41(rdev) && !ASIC_IS_DCE61(rdev)) {
 			/* ontario follows DCE4 */
 			if (rdev->family == CHIP_PALM) {
 				if (dig->linkb)