vc4_wait_for_seqno(struct drm_device *dev, uint64_t seqno, uint64_t timeout_ns,
		   bool interruptible)
{
	struct vc4_dev *vc4 = to_vc4_dev(dev);
	int ret = 0;
	unsigned long timeout_expire;
	DEFINE_WAIT(wait);

	if (vc4->finished_seqno >= seqno)
		return 0;

	if (timeout_ns == 0)
		return -ETIME;

	timeout_expire = jiffies + nsecs_to_jiffies(timeout_ns);

	trace_vc4_wait_for_seqno_begin(dev, seqno, timeout_ns);
	for (;;) {
		prepare_to_wait(&vc4->job_wait_queue, &wait,
				interruptible ? TASK_INTERRUPTIBLE :
				TASK_UNINTERRUPTIBLE);

		if (interruptible && signal_pending(current)) {
			ret = -ERESTARTSYS;
			break;
		}

		if (vc4->finished_seqno >= seqno)
			break;

		if (timeout_ns != ~0ull) {
			if (time_after_eq(jiffies, timeout_expire)) {
				ret = -ETIME;
				break;
			}
			schedule_timeout(timeout_expire - jiffies);
		} else {
			schedule();
		}
	}

	finish_wait(&vc4->job_wait_queue, &wait);
	trace_vc4_wait_for_seqno_end(dev, seqno);

	return ret;
}

This obsolete category once captured errors related to system feedback management, such as overly detailed error messages that might inadvertently disclose sensitive internal information.