Re: [PATCH 2/4] drm/bridge-connector: handle subconnector types

[Neil Armstrong <neil.armstrong@linaro.org>]

On 29/07/2023 02:49, Dmitry Baryshkov wrote:
> If the created connector type supports subconnector type property,
> create and attach corresponding it. The default subtype value is 0,
> which maps to the DRM_MODE_SUBCONNECTOR_Unknown type.
> 
> Signed-off-by: Dmitry Baryshkov <dmitry.baryshkov@linaro.org>
> ---
>   drivers/gpu/drm/drm_bridge_connector.c | 33 +++++++++++++++++++++++++-
>   include/drm/drm_bridge.h               |  4 ++++
>   2 files changed, 36 insertions(+), 1 deletion(-)
> 
> diff --git a/drivers/gpu/drm/drm_bridge_connector.c b/drivers/gpu/drm/drm_bridge_connector.c
> index 07b5930b1282..a7b92f0d2430 100644
> --- a/drivers/gpu/drm/drm_bridge_connector.c
> +++ b/drivers/gpu/drm/drm_bridge_connector.c
> @@ -329,7 +329,9 @@ struct drm_connector *drm_bridge_connector_init(struct drm_device *drm,
>   	struct drm_connector *connector;
>   	struct i2c_adapter *ddc = NULL;
>   	struct drm_bridge *bridge, *panel_bridge = NULL;
> +	enum drm_mode_subconnector subconnector;
>   	int connector_type;
> +	int ret;
>   
>   	bridge_connector = kzalloc(sizeof(*bridge_connector), GFP_KERNEL);
>   	if (!bridge_connector)
> @@ -365,8 +367,10 @@ struct drm_connector *drm_bridge_connector_init(struct drm_device *drm,
>   		if (bridge->ops & DRM_BRIDGE_OP_MODES)
>   			bridge_connector->bridge_modes = bridge;
>   
> -		if (!drm_bridge_get_next_bridge(bridge))
> +		if (!drm_bridge_get_next_bridge(bridge)) {
>   			connector_type = bridge->type;
> +			subconnector = bridge->subtype;
> +		}
>   
>   #ifdef CONFIG_OF
>   		if (!drm_bridge_get_next_bridge(bridge) &&
> @@ -399,6 +403,33 @@ struct drm_connector *drm_bridge_connector_init(struct drm_device *drm,
>   	if (panel_bridge)
>   		drm_panel_bridge_set_orientation(connector, panel_bridge);
>   
> +	if (connector_type == DRM_MODE_CONNECTOR_DisplayPort) {
> +		drm_connector_attach_dp_subconnector_property(connector, subconnector);
> +	} else if (connector_type == DRM_MODE_CONNECTOR_DVII) {
> +		ret = drm_mode_create_dvi_i_properties(drm);
> +		if (ret)
> +			return ERR_PTR(ret);
> +
> +		drm_object_attach_property(&connector->base,
> +					   drm->mode_config.dvi_i_subconnector_property,
> +					   subconnector);
> +	} else if (connector_type == DRM_MODE_CONNECTOR_TV) {
> +		ret = drm_mode_create_tv_properties(drm,
> +						    BIT(DRM_MODE_TV_MODE_NTSC) |
> +						    BIT(DRM_MODE_TV_MODE_NTSC_443) |
> +						    BIT(DRM_MODE_TV_MODE_NTSC_J) |
> +						    BIT(DRM_MODE_TV_MODE_PAL) |
> +						    BIT(DRM_MODE_TV_MODE_PAL_M) |
> +						    BIT(DRM_MODE_TV_MODE_PAL_N) |
> +						    BIT(DRM_MODE_TV_MODE_SECAM));
> +		if (ret)
> +			return ERR_PTR(ret);

I don't think this is right, this should be called from the appropriate encoder
device depending on the analog tv mode capabilities.


> +
> +		drm_object_attach_property(&connector->base,
> +					   drm->mode_config.tv_subconnector_property,
> +					   subconnector);

Here, only add the property if drm->mode_config.tv_subconnector_property exists,
and perhaps add a warning if not.

AFAIK same for DRM_MODE_CONNECTOR_DVII.

> +	}
> +
>   	return connector;
>   }
>   EXPORT_SYMBOL_GPL(drm_bridge_connector_init);
> diff --git a/include/drm/drm_bridge.h b/include/drm/drm_bridge.h
> index bf964cdfb330..68b14ac5ac0d 100644
> --- a/include/drm/drm_bridge.h
> +++ b/include/drm/drm_bridge.h
> @@ -739,6 +739,10 @@ struct drm_bridge {
>   	 * identifies the type of connected display.
>   	 */
>   	int type;
> +	/**
> +	 * @subtype: the subtype of the connector for the DP/TV/DVI-I cases.
> +	 */
> +	enum drm_mode_subconnector subtype;
>   	/**
>   	 * @interlace_allowed: Indicate that the bridge can handle interlaced
>   	 * modes.