static int genpd_runtime_resume()

in power/domain.c [942:1016]

• 57 lines of code
• 14 McCabe index (conditional complexity)

static int genpd_runtime_resume(struct device *dev)
{
	struct generic_pm_domain *genpd;
	struct generic_pm_domain_data *gpd_data = dev_gpd_data(dev);
	struct gpd_timing_data *td = &gpd_data->td;
	bool runtime_pm = pm_runtime_enabled(dev);
	ktime_t time_start;
	s64 elapsed_ns;
	int ret;
	bool timed = true;

	dev_dbg(dev, "%s()\n", __func__);

	genpd = dev_to_genpd(dev);
	if (IS_ERR(genpd))
		return -EINVAL;

	/*
	 * As we don't power off a non IRQ safe domain, which holds
	 * an IRQ safe device, we don't need to restore power to it.
	 */
	if (irq_safe_dev_in_no_sleep_domain(dev, genpd)) {
		timed = false;
		goto out;
	}

	genpd_lock(genpd);
	ret = genpd_power_on(genpd, 0);
	if (!ret)
		genpd_restore_performance_state(dev, gpd_data->rpm_pstate);
	genpd_unlock(genpd);

	if (ret)
		return ret;

 out:
	/* Measure resume latency. */
	time_start = 0;
	if (timed && runtime_pm)
		time_start = ktime_get();

	ret = genpd_start_dev(genpd, dev);
	if (ret)
		goto err_poweroff;

	ret = __genpd_runtime_resume(dev);
	if (ret)
		goto err_stop;

	/* Update resume latency value if the measured time exceeds it. */
	if (timed && runtime_pm) {
		elapsed_ns = ktime_to_ns(ktime_sub(ktime_get(), time_start));
		if (elapsed_ns > td->resume_latency_ns) {
			td->resume_latency_ns = elapsed_ns;
			dev_dbg(dev, "resume latency exceeded, %lld ns\n",
				elapsed_ns);
			genpd->max_off_time_changed = true;
			td->constraint_changed = true;
		}
	}

	return 0;

err_stop:
	genpd_stop_dev(genpd, dev);
err_poweroff:
	if (!pm_runtime_is_irq_safe(dev) || genpd_is_irq_safe(genpd)) {
		genpd_lock(genpd);
		gpd_data->rpm_pstate = genpd_drop_performance_state(dev);
		genpd_power_off(genpd, true, 0);
		genpd_unlock(genpd);
	}

	return ret;
}