drm/amdgpu/display: split dp connector registration (v4)

Split into init and register functions to avoid a segfault
in some configs when the load/unload callbacks are removed.

v2:
- add back accidently dropped has_aux setting
- set dev in late_register

v3:
- fix dp cec ordering

v4:
- squash in kdev reference fix
Reviewed-by: Daniel Vetter <daniel.vetter@ffwll.ch>
Tested-by: Thomas Zimmermann <tzimmermann@suse.de>
Signed-off-by: Alex Deucher <alexander.deucher@amd.com>

drivers/gpu/drm/amd/amdgpu/amdgpu_connectors.c

@@ -1461,6 +1461,20 @@ static enum drm_mode_status amdgpu_connector_dp_mode_valid(struct drm_connector
 	return MODE_OK;
 }
 
+static int
+amdgpu_connector_late_register(struct drm_connector *connector)
+{
+	struct amdgpu_connector *amdgpu_connector = to_amdgpu_connector(connector);
+	int r = 0;
+
+	if (amdgpu_connector->ddc_bus->has_aux) {
+		amdgpu_connector->ddc_bus->aux.dev = amdgpu_connector->base.kdev;
+		r = drm_dp_aux_register(&amdgpu_connector->ddc_bus->aux);
+	}
+
+	return r;
+}
+
 static const struct drm_connector_helper_funcs amdgpu_connector_dp_helper_funcs = {
 	.get_modes = amdgpu_connector_dp_get_modes,
 	.mode_valid = amdgpu_connector_dp_mode_valid,
@@ -1475,6 +1489,7 @@ static const struct drm_connector_funcs amdgpu_connector_dp_funcs = {
 	.early_unregister = amdgpu_connector_unregister,
 	.destroy = amdgpu_connector_destroy,
 	.force = amdgpu_connector_dvi_force,
+	.late_register = amdgpu_connector_late_register,
 };
 
 static const struct drm_connector_funcs amdgpu_connector_edp_funcs = {
@@ -1485,6 +1500,7 @@ static const struct drm_connector_funcs amdgpu_connector_edp_funcs = {
 	.early_unregister = amdgpu_connector_unregister,
 	.destroy = amdgpu_connector_destroy,
 	.force = amdgpu_connector_dvi_force,
+	.late_register = amdgpu_connector_late_register,
 };
 
 void

drivers/gpu/drm/amd/amdgpu/atombios_dp.c

@@ -186,16 +186,10 @@ amdgpu_atombios_dp_aux_transfer(struct drm_dp_aux *aux, struct drm_dp_aux_msg *m
 
 void amdgpu_atombios_dp_aux_init(struct amdgpu_connector *amdgpu_connector)
 {
-	int ret;
-
 	amdgpu_connector->ddc_bus->rec.hpd = amdgpu_connector->hpd.hpd;
-	amdgpu_connector->ddc_bus->aux.dev = amdgpu_connector->base.kdev;
 	amdgpu_connector->ddc_bus->aux.transfer = amdgpu_atombios_dp_aux_transfer;
-	ret = drm_dp_aux_register(&amdgpu_connector->ddc_bus->aux);
-	if (!ret)
-		amdgpu_connector->ddc_bus->has_aux = true;
-
-	WARN(ret, "drm_dp_aux_register_i2c_bus() failed with error %d\n", ret);
+	drm_dp_aux_init(&amdgpu_connector->ddc_bus->aux);
+	amdgpu_connector->ddc_bus->has_aux = true;
 }
 
 /***** general DP utility functions *****/

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

@@ -155,6 +155,12 @@ amdgpu_dm_mst_connector_late_register(struct drm_connector *connector)
 	struct amdgpu_dm_connector *amdgpu_dm_connector =
 		to_amdgpu_dm_connector(connector);
 	struct drm_dp_mst_port *port = amdgpu_dm_connector->port;
+	int r;
+
+	amdgpu_dm_connector->dm_dp_aux.aux.dev = connector->kdev;
+	r = drm_dp_aux_register(&amdgpu_dm_connector->dm_dp_aux.aux);
+	if (r)
+		return r;
 
 #if defined(CONFIG_DEBUG_FS)
 	connector_debugfs_init(amdgpu_dm_connector);
@@ -480,11 +486,10 @@ void amdgpu_dm_initialize_dp_connector(struct amdgpu_display_manager *dm,
 				       struct amdgpu_dm_connector *aconnector)
 {
 	aconnector->dm_dp_aux.aux.name = "dmdc";
-	aconnector->dm_dp_aux.aux.dev = aconnector->base.kdev;
 	aconnector->dm_dp_aux.aux.transfer = dm_dp_aux_transfer;
 	aconnector->dm_dp_aux.ddc_service = aconnector->dc_link->ddc;
 
-	drm_dp_aux_register(&aconnector->dm_dp_aux.aux);
+	drm_dp_aux_init(&aconnector->dm_dp_aux.aux);
 	drm_dp_cec_register_connector(&aconnector->dm_dp_aux.aux,
 				      &aconnector->base);