1 files changed, 16 insertions, 12 deletions

diff --git a/drivers/gpu/drm/amd/display/amdgpu_dm/amdgpu_dm_mst_types.c b/drivers/gpu/drm/amd/display/amdgpu_dm/amdgpu_dm_mst_types.c
index f3d87f418d2e..8291d74f26bc 100644
--- a/drivers/gpu/drm/amd/display/amdgpu_dm/amdgpu_dm_mst_types.c
+++ b/drivers/gpu/drm/amd/display/amdgpu_dm/amdgpu_dm_mst_types.c
@@ -83,17 +83,21 @@ static ssize_t dm_dp_aux_transfer(struct drm_dp_aux *aux,
 	enum i2c_mot_mode mot = (msg->request & DP_AUX_I2C_MOT) ?
 		I2C_MOT_TRUE : I2C_MOT_FALSE;
 	enum ddc_result res;
+	ssize_t read_bytes;
+
+	if (WARN_ON(msg->size > 16))
+		return -E2BIG;
 
 	switch (msg->request & ~DP_AUX_I2C_MOT) {
 	case DP_AUX_NATIVE_READ:
-		res = dal_ddc_service_read_dpcd_data(
+		read_bytes = dal_ddc_service_read_dpcd_data(
 				TO_DM_AUX(aux)->ddc_service,
 				false,
 				I2C_MOT_UNDEF,
 				msg->address,
 				msg->buffer,
 				msg->size);
-		break;
+		return read_bytes;
 	case DP_AUX_NATIVE_WRITE:
 		res = dal_ddc_service_write_dpcd_data(
 				TO_DM_AUX(aux)->ddc_service,
@@ -104,14 +108,14 @@ static ssize_t dm_dp_aux_transfer(struct drm_dp_aux *aux,
 				msg->size);
 		break;
 	case DP_AUX_I2C_READ:
-		res = dal_ddc_service_read_dpcd_data(
+		read_bytes = dal_ddc_service_read_dpcd_data(
 				TO_DM_AUX(aux)->ddc_service,
 				true,
 				mot,
 				msg->address,
 				msg->buffer,
 				msg->size);
-		break;
+		return read_bytes;
 	case DP_AUX_I2C_WRITE:
 		res = dal_ddc_service_write_dpcd_data(
 				TO_DM_AUX(aux)->ddc_service,
@@ -174,12 +178,6 @@ static const struct drm_connector_funcs dm_dp_mst_connector_funcs = {
 	.atomic_get_property = amdgpu_dm_connector_atomic_get_property
 };
 
-static int dm_connector_update_modes(struct drm_connector *connector,
-				struct edid *edid)
-{
-	return drm_add_edid_modes(connector, edid);
-}
-
 void dm_dp_mst_dc_sink_create(struct drm_connector *connector)
 {
 	struct amdgpu_dm_connector *aconnector = to_amdgpu_dm_connector(connector);
@@ -189,6 +187,12 @@ void dm_dp_mst_dc_sink_create(struct drm_connector *connector)
 			.link = aconnector->dc_link,
 			.sink_signal = SIGNAL_TYPE_DISPLAY_PORT_MST };
 
+	/*
+	 * TODO: Need to further figure out why ddc.algo is NULL while MST port exists
+	 */
+	if (!aconnector->port || !aconnector->port->aux.ddc.algo)
+		return;
+
 	edid = drm_dp_mst_get_edid(connector, &aconnector->mst_port->mst_mgr, aconnector->port);
 
 	if (!edid) {
@@ -222,7 +226,7 @@ static int dm_dp_mst_get_modes(struct drm_connector *connector)
 	int ret = 0;
 
 	if (!aconnector)
-		return dm_connector_update_modes(connector, NULL);
+		return drm_add_edid_modes(connector, NULL);
 
 	if (!aconnector->edid) {
 		struct edid *edid;
@@ -258,7 +262,7 @@ static int dm_dp_mst_get_modes(struct drm_connector *connector)
 						&aconnector->base, edid);
 	}
 
-	ret = dm_connector_update_modes(connector, aconnector->edid);
+	ret = drm_add_edid_modes(connector, aconnector->edid);
 
 	return ret;
 }