On Sat, Oct 18, 2025 at 04:01:21AM +0200, Louis Chauvet wrote:
> In order to allow creating dynamic connector, add the required
> infrastructure in vkms_connector.
>
> Co-developed-by: José Expósito <jose.exposito89@gmail.com>
> Signed-off-by: José Expósito <jose.exposito89@gmail.com>
> [Louis Chauvet: use drm_atomic_helper_connector_reset instead of
> drm_mode_config_reset because connector is not yet registered]
Aha! That was why, thanks a lot for figuring this out :)
> Signed-off-by: Louis Chauvet <louis.chauvet@bootlin.com>
> ---
> drivers/gpu/drm/vkms/vkms_connector.c | 69 ++++++++++++++++++++++++++++++++++-
> drivers/gpu/drm/vkms/vkms_connector.h | 33 +++++++++++++++++
> drivers/gpu/drm/vkms/vkms_output.c | 11 +++++-
> 3 files changed, 111 insertions(+), 2 deletions(-)
>
> diff --git a/drivers/gpu/drm/vkms/vkms_connector.c b/drivers/gpu/drm/vkms/vkms_connector.c
> index 339d747e729e..77a544728721 100644
> --- a/drivers/gpu/drm/vkms/vkms_connector.c
> +++ b/drivers/gpu/drm/vkms/vkms_connector.c
> @@ -1,5 +1,4 @@
> // SPDX-License-Identifier: GPL-2.0+
> -
> #include <drm/drm_atomic_helper.h>
> #include <drm/drm_edid.h>
> #include <drm/drm_managed.h>
> @@ -144,9 +143,77 @@ struct vkms_connector *vkms_connector_init(struct vkms_device *vkmsdev,
> return connector;
> }
>
> +static const struct drm_connector_funcs vkms_dynamic_connector_funcs = {
> + .fill_modes = drm_helper_probe_single_connector_modes,
> + .reset = drm_atomic_helper_connector_reset,
> + .atomic_duplicate_state = drm_atomic_helper_connector_duplicate_state,
> + .atomic_destroy_state = drm_atomic_helper_connector_destroy_state,
> + .destroy = drm_connector_cleanup,
> + .detect = vkms_connector_detect,
> +};
> +
> void vkms_trigger_connector_hotplug(struct vkms_device *vkmsdev)
> {
> struct drm_device *dev = &vkmsdev->drm;
>
> drm_kms_helper_hotplug_event(dev);
> }
> +
> +struct vkms_connector *vkms_connector_hot_add(struct vkms_device *vkmsdev,
> + struct vkms_config_connector *connector_cfg)
> +{
> + struct vkms_config_encoder *encoder_cfg;
> + struct vkms_connector *connector;
> + int ret;
> + unsigned long idx = 0;
> +
> + connector = kzalloc(sizeof(*connector), GFP_KERNEL);
Could we use drmm_kzalloc instead?
> + if (IS_ERR(connector))
> + return connector;
> + ret = drm_connector_dynamic_init(&vkmsdev->drm,
> + &connector->base,
> + &vkms_dynamic_connector_funcs,
> + connector_cfg->type,
> + NULL);
> + if (ret)
> + return ERR_PTR(ret);
> + drm_connector_helper_add(&connector->base, &vkms_conn_helper_funcs);
> +
> + vkms_config_connector_for_each_possible_encoder(connector_cfg, idx, encoder_cfg) {
> + ret = drm_connector_attach_encoder(&connector->base,
> + encoder_cfg->encoder);
> + if (ret)
> + return ERR_PTR(ret);
> + }
> +
> + drm_atomic_helper_connector_reset(&connector->base);
> +
> + ret = drm_connector_dynamic_register(&connector->base);
> + if (ret)
> + return ERR_PTR(ret);
> +
> + return connector;
> +}
> +
> +void vkms_connector_hot_remove(struct vkms_device *vkmsdev,
> + struct vkms_connector *connector)
> +{
> + drm_connector_unregister(&connector->base);
> + drm_mode_config_reset(&vkmsdev->drm);
> + drm_connector_put(&connector->base);
> +}
> +
> +int vkms_connector_hot_attach_encoder(struct vkms_device *vkmsdev,
> + struct vkms_connector *connector,
> + struct drm_encoder *encoder)
> +{
> + int ret;
> +
> + ret = drm_connector_attach_encoder(&connector->base, encoder);
> + if (ret)
> + return ret;
> +
> + drm_mode_config_reset(&vkmsdev->drm);
> +
> + return ret;
> +}
> diff --git a/drivers/gpu/drm/vkms/vkms_connector.h b/drivers/gpu/drm/vkms/vkms_connector.h
> index a124c5403697..224950c13a93 100644
> --- a/drivers/gpu/drm/vkms/vkms_connector.h
> +++ b/drivers/gpu/drm/vkms/vkms_connector.h
> @@ -7,6 +7,7 @@
>
> #define drm_connector_to_vkms_connector(target) \
> container_of(target, struct vkms_connector, base)
> +struct vkms_config_connector;
>
> /**
> * struct vkms_connector - VKMS custom type wrapping around the DRM connector
> @@ -33,4 +34,36 @@ struct vkms_connector *vkms_connector_init(struct vkms_device *vkmsdev,
> */
> void vkms_trigger_connector_hotplug(struct vkms_device *vkmsdev);
>
> +/**
> + * vkms_connector_hot_add() - Create a connector after the device is created
> + * @vkmsdev: Device to hot-add the connector to
> + * @connector_cfg: Connector's configuration
> + *
> + * Returns:
> + * The connector or an error on failure.
> + */
> +struct vkms_connector *vkms_connector_hot_add(struct vkms_device *vkmsdev,
> + struct vkms_config_connector *connector_cfg);
> +
> +/**
> + * vkms_connector_hot_remove() - Remove a connector after a device is created
> + * @connector: The connector to hot-remove
> + */
> +void vkms_connector_hot_remove(struct vkms_device *vkmsdev,
> + struct vkms_connector *connector);
> +
> +/**
> + * vkms_connector_hot_attach_encoder() - Attach a connector to a encoder after
> + * the device is created.
> + * @vkmsdev: Device containing the connector and the encoder
> + * @connector: Connector to attach to @encoder
> + * @encoder: Target encoder
> + *
> + * Returns:
> + * 0 on success or an error on failure.
> + */
> +int vkms_connector_hot_attach_encoder(struct vkms_device *vkmsdev,
> + struct vkms_connector *connector,
> + struct drm_encoder *encoder);
> +
> #endif /* _VKMS_CONNECTOR_H_ */
> diff --git a/drivers/gpu/drm/vkms/vkms_output.c b/drivers/gpu/drm/vkms/vkms_output.c
> index 217f054d9598..aba2f9ab243d 100644
> --- a/drivers/gpu/drm/vkms/vkms_output.c
> +++ b/drivers/gpu/drm/vkms/vkms_output.c
> @@ -92,7 +92,7 @@ int vkms_output_init(struct vkms_device *vkmsdev)
> }
> }
>
> - vkms_config_for_each_connector(vkmsdev->config, connector_cfg) {
> + vkms_config_for_each_connector_static(vkmsdev->config, connector_cfg) {
> struct vkms_config_encoder *possible_encoder;
> unsigned long idx = 0;
>
> @@ -116,5 +116,14 @@ int vkms_output_init(struct vkms_device *vkmsdev)
>
> drm_mode_config_reset(dev);
>
> + vkms_config_for_each_connector_dynamic(vkmsdev->config, connector_cfg) {
> + if (connector_cfg->enabled) {
> + connector_cfg->connector = vkms_connector_hot_add(vkmsdev, connector_cfg);
> +
> + if (IS_ERR(connector_cfg->connector))
> + return PTR_ERR(connector_cfg->connector);
> + }
> + }
> +
> return 0;
> }
>
> --
> 2.51.0
>