Re: [PATCH v2] drm/connector: Add of_drm_find_connector

[Andy Yan]

ping

On 7/3/20 5:45 PM, Andy Yan wrote:
> Add a function to look up a connector by
> device tree node, like what of_drm_find_bridge/panel
> does.
>
> Signed-off-by: Andy Yan <andy.yan@xxxxxxxxxxxxxx>
> Reported-by: kernel test robot <lkp@xxxxxxxxx>
>
> ---
>
> Changes in v2:
> - Add function declaration
>
>   drivers/gpu/drm/drm_connector.c | 33 +++++++++++++++++++++++++++++++++
>   include/drm/drm_connector.h     | 14 ++++++++++++++
>   2 files changed, 47 insertions(+)
>
> diff --git a/drivers/gpu/drm/drm_connector.c b/drivers/gpu/drm/drm_connector.c
> index d877ddc6dc57..516376cd1868 100644
> --- a/drivers/gpu/drm/drm_connector.c
> +++ b/drivers/gpu/drm/drm_connector.c
> @@ -743,6 +743,39 @@ void drm_connector_list_iter_end(struct drm_connector_list_iter *iter)
>   }
>   EXPORT_SYMBOL(drm_connector_list_iter_end);
>   
> +#ifdef CONFIG_OF
> +/**
> + * of_drm_find_connector - look up a connector using a device tree node
> + * @np: device tree node of the connector
> + *
> + *
> + * Return: A pointer to the connector which match the specified device tree
> + * node or NULL if no panel matching the device tree node can be found, or
> + * -ENODEV: the device is not available (status != "okay" or "ok")
> + */
> +struct drm_connector *of_drm_find_connector(struct drm_device *dev, const struct device_node *np)
> +{
> +	struct drm_connector *connector;
> +	struct drm_connector_list_iter conn_iter;
> +
> +	if (!of_device_is_available(np))
> +		return ERR_PTR(-ENODEV);
> +
> +	drm_connector_list_iter_begin(dev, &conn_iter);
> +	drm_for_each_connector_iter(connector, &conn_iter) {
> +		if (connector->of_node == np) {
> +			drm_connector_list_iter_end(&conn_iter);
> +			return connector;
> +		}
> +	}
> +	drm_connector_list_iter_end(&conn_iter);
> +
> +	return NULL;
> +}
> +EXPORT_SYMBOL(of_drm_find_connector);
> +#endif
> +
> +
>   static const struct drm_prop_enum_list drm_subpixel_enum_list[] = {
>   	{ SubPixelUnknown, "Unknown" },
>   	{ SubPixelHorizontalRGB, "Horizontal RGB" },
> diff --git a/include/drm/drm_connector.h b/include/drm/drm_connector.h
> index fd543d1db9b2..d249e0498375 100644
> --- a/include/drm/drm_connector.h
> +++ b/include/drm/drm_connector.h
> @@ -1129,6 +1129,9 @@ struct drm_connector {
>   	/** @attr: sysfs attributes */
>   	struct device_attribute *attr;
>   
> +	/** @of_node: device tree node */
> +	struct device_node *of_node;
> +
>   	/**
>   	 * @head:
>   	 *
> @@ -1647,6 +1650,17 @@ void drm_connector_list_iter_end(struct drm_connector_list_iter *iter);
>   bool drm_connector_has_possible_encoder(struct drm_connector *connector,
>   					struct drm_encoder *encoder);
>   
> +#if defined(CONFIG_OF)
> +struct drm_connector *
> +of_drm_find_connector(struct drm_device *dev, const struct device_node *np);
> +#else
> +static inline struct drm_connector *
> +of_drm_find_connector(struct drm_device *dev, const struct device_node *np)
> +{
> +	return ERR_PTR(-ENODEV);
> +}
> +#endif
> +
>   /**
>    * drm_for_each_connector_iter - connector_list iterator macro
>    * @connector: &struct drm_connector pointer used as cursor