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DRM_KMS_HELPER_POLL_(9) DRM Core DRM_KMS_HELPER_POLL_(9)

NAME

drm_kms_helper_poll_init - initialize and enable output polling

SYNOPSIS

void drm_kms_helper_poll_init(struct drm_device * dev);

ARGUMENTS

dev
drm_device

DESCRIPTION

This function intializes and then also enables output polling support for dev. Drivers which do not have reliable hotplug support in hardware can use this helper infrastructure to regularly poll such connectors for changes in their connection state.
Drivers can control which connectors are polled by setting the DRM_CONNECTOR_POLL_CONNECT and DRM_CONNECTOR_POLL_DISCONNECT flags. On connectors where probing live outputs can result in visual distortion drivers should not set the DRM_CONNECTOR_POLL_DISCONNECT flag to avoid this. Connectors which have no flag or only DRM_CONNECTOR_POLL_HPD set are completely ignored by the polling logic.
Note that a connector can be both polled and probed from the hotplug handler, in case the hotplug interrupt is known to be unreliable.

AUTHORS

Jesse Barnes <jesse.barnes@intel.com>
 
Intel Corporation,
Initial version
Laurent Pinchart <laurent.pinchart@ideasonboard.com>
 
Ideas on board SPRL,
Driver internals
Daniel Vetter <daniel.vetter@ffwll.ch>
 
Intel Corporation,
Contributions all over the place

COPYRIGHT

May 2018 Kernel Hackers Manual 3.16