[PATCH RESEND v3 1/6] drm/connector: report IRQ_HPD events to drm_connector_oob_hotplug_event()

Maxime Ripard mripard at kernel.org
Thu May 21 00:47:29 PDT 2026


On Wed, May 13, 2026 at 09:23:21PM +0300, Dmitry Baryshkov wrote:
> The DisplayPort standard defines a special kind of events called IRQ.
> These events are used to notify DP Source about the events on the Sink
> side. It is extremely important for DP MST handling, where the MST
> events are reported through this IRQ.
> 
> In case of the USB-C DP AltMode there is no actual HPD pulse, but the
> events are ported through the bits in the AltMode VDOs.
> 
> Extend the drm_connector_oob_hotplug_event() interface and report IRQ
> events to the DisplayPort Sink drivers.
> 
> Signed-off-by: Dmitry Baryshkov <dmitry.baryshkov at oss.qualcomm.com>
> ---
>  drivers/gpu/drm/drm_connector.c          |  5 ++++-
>  drivers/usb/typec/altmodes/displayport.c | 15 +++++++++++----
>  include/drm/drm_connector.h              | 19 ++++++++++++++++++-
>  3 files changed, 33 insertions(+), 6 deletions(-)
> 
> diff --git a/drivers/gpu/drm/drm_connector.c b/drivers/gpu/drm/drm_connector.c
> index 47dc53c4a738..edee9daccd51 100644
> --- a/drivers/gpu/drm/drm_connector.c
> +++ b/drivers/gpu/drm/drm_connector.c
> @@ -3510,6 +3510,8 @@ struct drm_connector *drm_connector_find_by_fwnode(struct fwnode_handle *fwnode)
>   * drm_connector_oob_hotplug_event - Report out-of-band hotplug event to connector
>   * @connector_fwnode: fwnode_handle to report the event on
>   * @status: hot plug detect logical state
> + * @extra_status: additional information provided by the sink without changing
> + * the HPD state (or in addition to such a change).
>   *
>   * On some hardware a hotplug event notification may come from outside the display
>   * driver / device. An example of this is some USB Type-C setups where the hardware
> @@ -3520,7 +3522,8 @@ struct drm_connector *drm_connector_find_by_fwnode(struct fwnode_handle *fwnode)
>   * a drm_connector reference through calling drm_connector_find_by_fwnode().
>   */
>  void drm_connector_oob_hotplug_event(struct fwnode_handle *connector_fwnode,
> -				     enum drm_connector_status status)
> +				     enum drm_connector_status status,
> +				     enum drm_connector_status_extra extra_status)
>  {
>  	struct drm_connector *connector;
>  
> diff --git a/drivers/usb/typec/altmodes/displayport.c b/drivers/usb/typec/altmodes/displayport.c
> index 35d9c3086990..7182a8e2e710 100644
> --- a/drivers/usb/typec/altmodes/displayport.c
> +++ b/drivers/usb/typec/altmodes/displayport.c
> @@ -189,7 +189,9 @@ static int dp_altmode_status_update(struct dp_altmode *dp)
>  	} else {
>  		drm_connector_oob_hotplug_event(dp->connector_fwnode,
>  						hpd ? connector_status_connected :
> -						      connector_status_disconnected);
> +						      connector_status_disconnected,
> +						(hpd && irq_hpd) ? DRM_CONNECTOR_DP_IRQ_HPD :
> +								   DRM_CONNECTOR_NO_EXTRA_STATUS);

Since the extra status itself, and what the options mean, are DP specific, do we really want to
extend drm_connector_oob_hotplug_event()? I think I'd prefer to have a DP specific variant, with its
own set of parameters.

Maxime
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