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Connector link-status property to indicate the status of link. The default value of link-status is "GOOD". If something fails during or after modeset, the kernel driver may set this to "BAD" and issue a hotplug uevent. Drivers should update this value using drm_connector_set_link_status_property(). When user-space receives the hotplug uevent and detects a "BAD" link-status, the sink doesn't receive pixels anymore (e.g. the screen becomes completely black). The list of available modes may have changed. User-space is expected to pick a new mode if the current one has disappeared and perform a new modeset with link-status set to "GOOD" to re-enable the connector. If multiple connectors share the same CRTC and one of them gets a "BAD" link-status, the other are unaffected (ie. the sinks still continue to receive pixels). When user-space performs an atomic commit on a connector with a "BAD" link-status without resetting the property to "GOOD", the sink may still not receive pixels. When user-space performs an atomic commit which resets the link-status property to "GOOD" without the ALLOW_MODESET flag set, it might fail because a modeset is required. User-space can only change link-status to "GOOD", changing it to "BAD" is a no-op. For backwards compatibility with non-atomic userspace the kernel tries to automatically set the link-status back to "GOOD" in the SETCRTC IOCTL. This might fail if the mode is no longer valid, similar to how it might fail if a different screen has been connected in the interim.