Re: [PATCH RESEND v7 1/2] drm: Introduce pending_hp to drm_connector

[Dmitry Baryshkov]

On Wed, Apr 15, 2026 at 07:59:39PM +0200, Nicolas Frattaroli wrote:
> From: Marius Vlad <marius.vlad@xxxxxxxxxxxxx>
> 
> Introduce a new boolean variable used to track whether a connector has
> changed its status since the last hotplug event for it was sent to
> userspace. It is used by both the polling and HPD path.
> 
> A subsequent change will make use of this new member to propagate
> per-connector udev hotplug events to userspace, rather than sending a
> global hotplug event.
> 
> Signed-off-by: Marius Vlad <marius.vlad@xxxxxxxxxxxxx>
> Signed-off-by: Nicolas Frattaroli <nicolas.frattaroli@xxxxxxxxxxxxx>
> ---
>  drivers/gpu/drm/drm_connector.c    |  1 +
>  drivers/gpu/drm/drm_probe_helper.c | 17 +++++++++++++++++
>  drivers/gpu/drm/drm_sysfs.c        |  2 ++
>  include/drm/drm_connector.h        |  3 +++
>  4 files changed, 23 insertions(+)
> 
> diff --git a/drivers/gpu/drm/drm_connector.c b/drivers/gpu/drm/drm_connector.c
> index 3fa4d2082cd7..b1abdef6778a 100644
> --- a/drivers/gpu/drm/drm_connector.c
> +++ b/drivers/gpu/drm/drm_connector.c
> @@ -274,6 +274,7 @@ static int drm_connector_init_only(struct drm_device *dev,
>  
>  	/* provide ddc symlink in sysfs */
>  	connector->ddc = ddc;
> +	connector->pending_hp = false;

Can we use epoch_counter directly instead of adding a new property?

>  
>  	INIT_LIST_HEAD(&connector->head);
>  	INIT_LIST_HEAD(&connector->global_connector_list_entry);
> diff --git a/drivers/gpu/drm/drm_probe_helper.c b/drivers/gpu/drm/drm_probe_helper.c
> index d4dc8cb45bce..f8cbd6713960 100644
> --- a/drivers/gpu/drm/drm_probe_helper.c
> +++ b/drivers/gpu/drm/drm_probe_helper.c
> @@ -732,6 +732,17 @@ EXPORT_SYMBOL(drm_helper_probe_single_connector_modes);
>   */
>  void drm_kms_helper_hotplug_event(struct drm_device *dev)
>  {
> +	struct drm_connector *connector;
> +	struct drm_connector_list_iter conn_iter;
> +
> +	mutex_lock(&dev->mode_config.mutex);
> +	drm_connector_list_iter_begin(dev, &conn_iter);
> +	drm_for_each_connector_iter(connector, &conn_iter) {
> +		connector->pending_hp = false;
> +	}
> +	drm_connector_list_iter_end(&conn_iter);
> +	mutex_unlock(&dev->mode_config.mutex);
> +
>  	drm_sysfs_hotplug_event(dev);
>  	drm_client_dev_hotplug(dev);
>  }
> @@ -748,6 +759,10 @@ void drm_kms_helper_connector_hotplug_event(struct drm_connector *connector)
>  {
>  	struct drm_device *dev = connector->dev;
>  
> +	mutex_lock(&dev->mode_config.mutex);
> +	connector->pending_hp = false;
> +	mutex_unlock(&dev->mode_config.mutex);
> +
>  	drm_sysfs_connector_hotplug_event(connector);
>  	drm_client_dev_hotplug(dev);
>  }
> @@ -837,6 +852,7 @@ static void output_poll_execute(struct work_struct *work)
>  				    old_epoch_counter, connector->epoch_counter);
>  
>  			changed = true;
> +			connector->pending_hp = true;
>  		}
>  	}
>  	drm_connector_list_iter_end(&conn_iter);
> @@ -1101,6 +1117,7 @@ bool drm_helper_hpd_irq_event(struct drm_device *dev)
>  				first_changed_connector = connector;
>  			}
>  
> +			connector->pending_hp = true;
>  			changed++;
>  		}
>  	}
> diff --git a/drivers/gpu/drm/drm_sysfs.c b/drivers/gpu/drm/drm_sysfs.c
> index ef4e923a8728..47a6b322e873 100644
> --- a/drivers/gpu/drm/drm_sysfs.c
> +++ b/drivers/gpu/drm/drm_sysfs.c
> @@ -216,6 +216,8 @@ static ssize_t status_store(struct device *device,
>  			    connector->base.id, connector->name,
>  			    old_force, connector->force);
>  
> +		connector->pending_hp = true;
> +
>  		connector->funcs->fill_modes(connector,
>  					     dev->mode_config.max_width,
>  					     dev->mode_config.max_height);
> diff --git a/include/drm/drm_connector.h b/include/drm/drm_connector.h
> index 3e422a4f2e72..70a740301089 100644
> --- a/include/drm/drm_connector.h
> +++ b/include/drm/drm_connector.h
> @@ -2251,6 +2251,9 @@ struct drm_connector {
>  	/** @force: a DRM_FORCE_<foo> state for forced mode sets */
>  	enum drm_connector_force force;
>  
> +	/** @pending_hp: true if connector changed since last hotplug event */
> +	bool pending_hp;
> +
>  	/**
>  	 * @edid_override: Override EDID set via debugfs.
>  	 *
> 
> -- 
> 2.53.0
> 

-- 
With best wishes
Dmitry