Re: [PATCH v3 01/20] drm/amdgpu: Add error handling to amdgpu_dm_initialize_dp_connector()

[Mikita Lipski]

Thanks for the change!

Reviewed-by: Mikita Lipski <Mikita.Lipski@xxxxxxx>

On 2021-04-19 6:55 p.m., Lyude Paul wrote:
> While working on moving i2c device registration into drm_dp_aux_init() - I
> realized that in order to do so we need to make sure that drivers calling
> drm_dp_aux_init() handle any errors it could possibly return. In the
> process of doing that, I noticed that the majority of AMD's code for DP
> connector creation doesn't attempt to do any real error handling.
>
> So, let's fix this and also cleanup amdgpu_dm_initialize_dp_connector()
> while we're at it. This way we can handle the error codes from
> drm_dp_aux_init().
>
> Signed-off-by: Lyude Paul <lyude@xxxxxxxxxx>
> ---
>   .../gpu/drm/amd/display/amdgpu_dm/amdgpu_dm.c | 29 +++++++-----
>   .../display/amdgpu_dm/amdgpu_dm_mst_types.c   | 44 +++++++++++--------
>   .../display/amdgpu_dm/amdgpu_dm_mst_types.h   |  6 +--
>   3 files changed, 45 insertions(+), 34 deletions(-)
>
> diff --git a/drivers/gpu/drm/amd/display/amdgpu_dm/amdgpu_dm.c b/drivers/gpu/drm/amd/display/amdgpu_dm/amdgpu_dm.c
> index a0c8c41e4e57..fc5d315bbb05 100644
> --- a/drivers/gpu/drm/amd/display/amdgpu_dm/amdgpu_dm.c
> +++ b/drivers/gpu/drm/amd/display/amdgpu_dm/amdgpu_dm.c
> @@ -7608,10 +7608,9 @@ static int amdgpu_dm_connector_init(struct amdgpu_display_manager *dm,
>   
>   	aconnector->i2c = i2c;
>   	res = i2c_add_adapter(&i2c->base);
> -
>   	if (res) {
>   		DRM_ERROR("Failed to register hw i2c %d\n", link->link_index);
> -		goto out_free;
> +		goto fail_free;
>   	}
>   
>   	connector_type = to_drm_connector_type(link->connector_signal);
> @@ -7625,8 +7624,7 @@ static int amdgpu_dm_connector_init(struct amdgpu_display_manager *dm,
>   
>   	if (res) {
>   		DRM_ERROR("connector_init failed\n");
> -		aconnector->connector_id = -1;
> -		goto out_free;
> +		goto fail_id;
>   	}
>   
>   	drm_connector_helper_add(
> @@ -7643,15 +7641,22 @@ static int amdgpu_dm_connector_init(struct amdgpu_display_manager *dm,
>   	drm_connector_attach_encoder(
>   		&aconnector->base, &aencoder->base);
>   
> -	if (connector_type == DRM_MODE_CONNECTOR_DisplayPort
> -		|| connector_type == DRM_MODE_CONNECTOR_eDP)
> -		amdgpu_dm_initialize_dp_connector(dm, aconnector, link->link_index);
> -
> -out_free:
> -	if (res) {
> -		kfree(i2c);
> -		aconnector->i2c = NULL;
> +	if (connector_type == DRM_MODE_CONNECTOR_DisplayPort ||
> +	    connector_type == DRM_MODE_CONNECTOR_eDP) {
> +		res = amdgpu_dm_initialize_dp_connector(dm, aconnector, link->link_index);
> +		if (res)
> +			goto fail_cleanup;
>   	}
> +
> +	return 0;
> +fail_cleanup:
> +	drm_connector_cleanup(&aconnector->base);
> +fail_id:
> +	aconnector->connector_id = -1;
> +fail_free:
> +	kfree(i2c);
> +	aconnector->i2c = NULL;
> +
>   	return res;
>   }
>   
> 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 73cdb9fe981a..3dee9cce9c9e 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
> @@ -425,33 +425,39 @@ static const struct drm_dp_mst_topology_cbs dm_mst_cbs = {
>   	.add_connector = dm_dp_add_mst_connector,
>   };
>   
> -void amdgpu_dm_initialize_dp_connector(struct amdgpu_display_manager *dm,
> -				       struct amdgpu_dm_connector *aconnector,
> -				       int link_index)
> +int amdgpu_dm_initialize_dp_connector(struct amdgpu_display_manager *dm,
> +				      struct amdgpu_dm_connector *aconnector,
> +				      int link_index)
>   {
> -	aconnector->dm_dp_aux.aux.name =
> -		kasprintf(GFP_KERNEL, "AMDGPU DM aux hw bus %d",
> -			  link_index);
> -	aconnector->dm_dp_aux.aux.transfer = dm_dp_aux_transfer;
> -	aconnector->dm_dp_aux.ddc_service = aconnector->dc_link->ddc;
> +	struct amdgpu_dm_dp_aux *dm_aux = &aconnector->dm_dp_aux;
> +	int ret;
>   
> -	drm_dp_aux_init(&aconnector->dm_dp_aux.aux);
> -	drm_dp_cec_register_connector(&aconnector->dm_dp_aux.aux,
> -				      &aconnector->base);
> +	dm_aux->aux.name = kasprintf(GFP_KERNEL, "AMDGPU DM aux hw bus %d", link_index);
> +	if (!dm_aux->aux.name)
> +		return -ENOMEM;
> +
> +	dm_aux->aux.transfer = dm_dp_aux_transfer;
> +	dm_aux->ddc_service = aconnector->dc_link->ddc;
> +
> +	drm_dp_aux_init(&dm_aux->aux);
> +	drm_dp_cec_register_connector(&dm_aux->aux, &aconnector->base);
>   
>   	if (aconnector->base.connector_type == DRM_MODE_CONNECTOR_eDP)
> -		return;
> +		return 0;
>   
>   	aconnector->mst_mgr.cbs = &dm_mst_cbs;
> -	drm_dp_mst_topology_mgr_init(
> -		&aconnector->mst_mgr,
> -		adev_to_drm(dm->adev),
> -		&aconnector->dm_dp_aux.aux,
> -		16,
> -		4,
> -		aconnector->connector_id);
> +	ret = drm_dp_mst_topology_mgr_init(&aconnector->mst_mgr, adev_to_drm(dm->adev),
> +					   &dm_aux->aux, 16, 4, aconnector->connector_id);
> +	if (ret)
> +		goto unreg_cec;
>   
>   	drm_connector_attach_dp_subconnector_property(&aconnector->base);
> +
> +	return 0;
> +unreg_cec:
> +	drm_dp_cec_unregister_connector(&dm_aux->aux);
> +	kfree(dm_aux->aux.name);
> +	return ret;
>   }
>   
>   int dm_mst_get_pbn_divider(struct dc_link *link)
> diff --git a/drivers/gpu/drm/amd/display/amdgpu_dm/amdgpu_dm_mst_types.h b/drivers/gpu/drm/amd/display/amdgpu_dm/amdgpu_dm_mst_types.h
> index b38bd68121ce..cf771ff58bb3 100644
> --- a/drivers/gpu/drm/amd/display/amdgpu_dm/amdgpu_dm_mst_types.h
> +++ b/drivers/gpu/drm/amd/display/amdgpu_dm/amdgpu_dm_mst_types.h
> @@ -31,9 +31,9 @@ struct amdgpu_dm_connector;
>   
>   int dm_mst_get_pbn_divider(struct dc_link *link);
>   
> -void amdgpu_dm_initialize_dp_connector(struct amdgpu_display_manager *dm,
> -				       struct amdgpu_dm_connector *aconnector,
> -				       int link_index);
> +int amdgpu_dm_initialize_dp_connector(struct amdgpu_display_manager *dm,
> +				      struct amdgpu_dm_connector *aconnector,
> +				      int link_index);
>   
>   void
>   dm_dp_create_fake_mst_encoders(struct amdgpu_device *adev);