drm/amd/display: Return drm_connector from find_first_crtc_matching_connector

[WHY]
We will be dealing with two types of connector: amdgpu_dm_connector
and drm_writeback_connector.

[HOW]
We want to find both and then cast to the appriopriate type afterwards.
Reviewed-by: Alex Hung <alex.hung@amd.com>
Signed-off-by: Harry Wentland <harry.wentland@amd.com>
Signed-off-by: Alex Hung <alex.hung@amd.com>
Signed-off-by: Alex Deucher <alexander.deucher@amd.com>

drivers/gpu/drm/amd/display/amdgpu_dm/amdgpu_dm.c

@@ -2699,7 +2699,7 @@ static int dm_suspend(void *handle)
 	return dm_set_power_state(dm->dc, DC_ACPI_CM_POWER_STATE_D3);
 }
 
-struct amdgpu_dm_connector *
+struct drm_connector *
 amdgpu_dm_find_first_crtc_matching_connector(struct drm_atomic_state *state,
 					     struct drm_crtc *crtc)
 {
@@ -2712,7 +2712,7 @@ amdgpu_dm_find_first_crtc_matching_connector(struct drm_atomic_state *state,
 		crtc_from_state = new_con_state->crtc;
 
 		if (crtc_from_state == crtc)
-			return to_amdgpu_dm_connector(connector);
+			return connector;
 	}
 
 	return NULL;
@@ -9439,6 +9439,7 @@ static int dm_update_crtc_state(struct amdgpu_display_manager *dm,
 	 * update changed items
 	 */
 	struct amdgpu_crtc *acrtc = NULL;
+	struct drm_connector *connector = NULL;
 	struct amdgpu_dm_connector *aconnector = NULL;
 	struct drm_connector_state *drm_new_conn_state = NULL, *drm_old_conn_state = NULL;
 	struct dm_connector_state *dm_new_conn_state = NULL, *dm_old_conn_state = NULL;
@@ -9448,7 +9449,8 @@ static int dm_update_crtc_state(struct amdgpu_display_manager *dm,
 	dm_old_crtc_state = to_dm_crtc_state(old_crtc_state);
 	dm_new_crtc_state = to_dm_crtc_state(new_crtc_state);
 	acrtc = to_amdgpu_crtc(crtc);
-	aconnector = amdgpu_dm_find_first_crtc_matching_connector(state, crtc);
+	connector = amdgpu_dm_find_first_crtc_matching_connector(state, crtc);
+	aconnector = to_amdgpu_dm_connector(connector);
 
 	/* TODO This hack should go away */
 	if (aconnector && enable) {

drivers/gpu/drm/amd/display/amdgpu_dm/amdgpu_dm.h

@@ -834,7 +834,7 @@ struct dc_stream_state *
 int dm_atomic_get_state(struct drm_atomic_state *state,
 			struct dm_atomic_state **dm_state);
 
-struct amdgpu_dm_connector *
+struct drm_connector *
 amdgpu_dm_find_first_crtc_matching_connector(struct drm_atomic_state *state,
 					     struct drm_crtc *crtc);
 

drivers/gpu/drm/amd/display/amdgpu_dm/amdgpu_dm_mst_types.c

@@ -1500,14 +1500,16 @@ int pre_validate_dsc(struct drm_atomic_state *state,
 		int ind = find_crtc_index_in_state_by_stream(state, stream);
 
 		if (ind >= 0) {
+			struct drm_connector *connector;
 			struct amdgpu_dm_connector *aconnector;
 			struct drm_connector_state *drm_new_conn_state;
 			struct dm_connector_state *dm_new_conn_state;
 			struct dm_crtc_state *dm_old_crtc_state;
 
-			aconnector =
+			connector =
 				amdgpu_dm_find_first_crtc_matching_connector(state,
 									     state->crtcs[ind].ptr);
+			aconnector = to_amdgpu_dm_connector(connector);
 			drm_new_conn_state =
 				drm_atomic_get_new_connector_state(state,
 								   &aconnector->base);