[PATCH] drm/radeon/kms: fix radeon_dp_get_modes for LVDS bridges (v2)

[alexdeucher at gmail.com]

From: Alex Deucher <alexander.deucher at amd.com>

Need to call ExternalEncoderControl to set up DDC before
trying to get an EDID for all DP bridge chips (including
DP to LVDS).

Also remove redundant encoder assignment.

V2: fix typo in commit message.

Signed-off-by: Alex Deucher <alexander.deucher at amd.com>
---
 drivers/gpu/drm/radeon/radeon_connectors.c |   25 +++++++++++++++++--------
 1 files changed, 17 insertions(+), 8 deletions(-)

diff --git a/drivers/gpu/drm/radeon/radeon_connectors.c b/drivers/gpu/drm/radeon/radeon_connectors.c
index e7cb3ab..8b3d8ed 100644
--- a/drivers/gpu/drm/radeon/radeon_connectors.c
+++ b/drivers/gpu/drm/radeon/radeon_connectors.c
@@ -1117,13 +1117,23 @@ static int radeon_dp_get_modes(struct drm_connector *connector)
 	    (connector->connector_type == DRM_MODE_CONNECTOR_LVDS)) {
 		struct drm_display_mode *mode;
 
-		if (!radeon_dig_connector->edp_on)
-			atombios_set_edp_panel_power(connector,
-						     ATOM_TRANSMITTER_ACTION_POWER_ON);
-		ret = radeon_ddc_get_modes(radeon_connector);
-		if (!radeon_dig_connector->edp_on)
-			atombios_set_edp_panel_power(connector,
-						     ATOM_TRANSMITTER_ACTION_POWER_OFF);
+		if (connector->connector_type == DRM_MODE_CONNECTOR_eDP) {
+			if (!radeon_dig_connector->edp_on)
+				atombios_set_edp_panel_power(connector,
+							     ATOM_TRANSMITTER_ACTION_POWER_ON);
+			ret = radeon_ddc_get_modes(radeon_connector);
+			if (!radeon_dig_connector->edp_on)
+				atombios_set_edp_panel_power(connector,
+							     ATOM_TRANSMITTER_ACTION_POWER_OFF);
+		} else {
+			/* need to setup ddc on the bridge */
+			if (radeon_connector_encoder_get_dp_bridge_encoder_id(connector) !=
+			    ENCODER_OBJECT_ID_NONE) {
+				if (encoder)
+					radeon_atom_ext_encoder_setup_ddc(encoder);
+			}
+			ret = radeon_ddc_get_modes(radeon_connector);
+		}
 
 		if (ret > 0) {
 			if (encoder) {
@@ -1134,7 +1144,6 @@ static int radeon_dp_get_modes(struct drm_connector *connector)
 			return ret;
 		}
 
-		encoder = radeon_best_single_encoder(connector);
 		if (!encoder)
 			return 0;
 
-- 
1.7.7.5