Re: [PATCH v6 16/16] drm/vkms: Allow to configure connector status via configfs

[Harry Wentland <harry.wentland@amd.com>]

On 2025-09-01 08:25, José Expósito wrote:
> When a connector is created, add a `status` file to allow to update the
> connector status to:
> 
>   - 1 connector_status_connected
>   - 2 connector_status_disconnected
>   - 3 connector_status_unknown
> 
> If the device is enabled, updating the status hot-plug or unplugs the
> connector.
> 
> Tested-by: Mark Yacoub <markyacoub@google.com>
> Reviewed-by: Louis Chauvet <louis.chauvet@bootlin.com>
> Signed-off-by: José Expósito <jose.exposito89@gmail.com>
> ---
>   Documentation/gpu/vkms.rst            |  5 +++
>   drivers/gpu/drm/vkms/vkms_configfs.c  | 48 +++++++++++++++++++++++++++
>   drivers/gpu/drm/vkms/vkms_connector.c |  7 ++++
>   drivers/gpu/drm/vkms/vkms_connector.h |  6 ++++
>   4 files changed, 66 insertions(+)
> 
> diff --git a/Documentation/gpu/vkms.rst b/Documentation/gpu/vkms.rst
> index 364b574a8cae..3574e01b928d 100644
> --- a/Documentation/gpu/vkms.rst
> +++ b/Documentation/gpu/vkms.rst
> @@ -108,6 +108,11 @@ Last but not least, create one or more connectors::
>   
>     sudo mkdir /config/vkms/my-vkms/connectors/connector0
>   
> +Connectors have 1 configurable attribute:
> +
> +- status: Connection status: 1 connected, 2 disconnected, 3 unknown (same values
> +  as those exposed by the "status" property of a connector)
> +
>   To finish the configuration, link the different pipeline items::
>   
>     sudo ln -s /config/vkms/my-vkms/crtcs/crtc0 /config/vkms/my-vkms/planes/plane0/possible_crtcs
> diff --git a/drivers/gpu/drm/vkms/vkms_configfs.c b/drivers/gpu/drm/vkms/vkms_configfs.c
> index 8e90acbebd6a..07ab794e1052 100644
> --- a/drivers/gpu/drm/vkms/vkms_configfs.c
> +++ b/drivers/gpu/drm/vkms/vkms_configfs.c
> @@ -7,6 +7,7 @@
>   #include "vkms_drv.h"
>   #include "vkms_config.h"
>   #include "vkms_configfs.h"
> +#include "vkms_connector.h"
>   
>   /* To avoid registering configfs more than once or unregistering on error */
>   static bool is_configfs_registered;
> @@ -512,6 +513,52 @@ static const struct config_item_type encoder_group_type = {
>   	.ct_owner	= THIS_MODULE,
>   };
>   
> +static ssize_t connector_status_show(struct config_item *item, char *page)
> +{
> +	struct vkms_configfs_connector *connector;
> +	enum drm_connector_status status;
> +
> +	connector = connector_item_to_vkms_configfs_connector(item);
> +
> +	scoped_guard(mutex, &connector->dev->lock)
> +		status = vkms_config_connector_get_status(connector->config);
> +
> +	return sprintf(page, "%u", status);
> +}
> +
> +static ssize_t connector_status_store(struct config_item *item,
> +				      const char *page, size_t count)
> +{
> +	struct vkms_configfs_connector *connector;
> +	enum drm_connector_status status;
> +
> +	connector = connector_item_to_vkms_configfs_connector(item);
> +
> +	if (kstrtouint(page, 10, &status))
> +		return -EINVAL;
> +
> +	if (status != connector_status_connected &&
> +	    status != connector_status_disconnected &&
> +	    status != connector_status_unknown)
> +		return -EINVAL;
> +
> +	scoped_guard(mutex, &connector->dev->lock) {
> +		vkms_config_connector_set_status(connector->config, status);
> +
> +		if (connector->dev->enabled)
> +			vkms_trigger_connector_hotplug(connector->dev->config->dev);
> +	}
> +
> +	return (ssize_t)count;
> +}
> +
> +CONFIGFS_ATTR(connector_, status);
> +
> +static struct configfs_attribute *connector_item_attrs[] = {
> +	&connector_attr_status,
> +	NULL,
> +};
> +
>   static void connector_release(struct config_item *item)
>   {
>   	struct vkms_configfs_connector *connector;
> @@ -531,6 +578,7 @@ static struct configfs_item_operations connector_item_operations = {
>   };
>   
>   static const struct config_item_type connector_item_type = {
> +	.ct_attrs	= connector_item_attrs,
>   	.ct_item_ops	= &connector_item_operations,
>   	.ct_owner	= THIS_MODULE,
>   };
> diff --git a/drivers/gpu/drm/vkms/vkms_connector.c b/drivers/gpu/drm/vkms/vkms_connector.c
> index 89fa8d9d739b..b0a6b212d3f4 100644
> --- a/drivers/gpu/drm/vkms/vkms_connector.c
> +++ b/drivers/gpu/drm/vkms/vkms_connector.c
> @@ -87,3 +87,10 @@ struct vkms_connector *vkms_connector_init(struct vkms_device *vkmsdev)
>   
>   	return connector;
>   }
> +
> +void vkms_trigger_connector_hotplug(struct vkms_device *vkmsdev)
> +{
> +	struct drm_device *dev = &vkmsdev->drm;
> +
> +	drm_kms_helper_hotplug_event(dev);
> +}
> diff --git a/drivers/gpu/drm/vkms/vkms_connector.h b/drivers/gpu/drm/vkms/vkms_connector.h
> index 90f835f70b3b..35f2adf97e32 100644
> --- a/drivers/gpu/drm/vkms/vkms_connector.h
> +++ b/drivers/gpu/drm/vkms/vkms_connector.h
> @@ -26,4 +26,10 @@ struct vkms_connector {
>    */
>   struct vkms_connector *vkms_connector_init(struct vkms_device *vkmsdev);
>   
> +/**
> + * struct vkms_device *vkmsdev() - Update the device's connectors status

vkms_trigger_connector_hotplug()

(or something like that)

After fixing I recommend running 'make htmldocs' and checking for 
errors/warnings in the new changes.

Harry

> + * @vkmsdev: VKMS device to update
> + */
> +void vkms_trigger_connector_hotplug(struct vkms_device *vkmsdev);
> +
>   #endif /* _VKMS_CONNECTOR_H_ */