static int __maybe_unused intel_resume()

in intel.c [1718:1811]

• 60 lines of code
• 12 McCabe index (conditional complexity)

static int __maybe_unused intel_resume(struct device *dev)
{
	struct sdw_cdns *cdns = dev_get_drvdata(dev);
	struct sdw_intel *sdw = cdns_to_intel(cdns);
	struct sdw_bus *bus = &cdns->bus;
	int link_flags;
	bool multi_link;
	int ret;

	if (bus->prop.hw_disabled || !sdw->startup_done) {
		dev_dbg(dev, "SoundWire master %d is disabled or not-started, ignoring\n",
			bus->link_id);
		return 0;
	}

	link_flags = md_flags >> (bus->link_id * 8);
	multi_link = !(link_flags & SDW_INTEL_MASTER_DISABLE_MULTI_LINK);

	if (pm_runtime_suspended(dev)) {
		dev_dbg(dev, "%s: pm_runtime status was suspended, forcing active\n", __func__);

		/* follow required sequence from runtime_pm.rst */
		pm_runtime_disable(dev);
		pm_runtime_set_active(dev);
		pm_runtime_mark_last_busy(dev);
		pm_runtime_enable(dev);

		link_flags = md_flags >> (bus->link_id * 8);

		if (!(link_flags & SDW_INTEL_MASTER_DISABLE_PM_RUNTIME_IDLE))
			pm_runtime_idle(dev);
	}

	ret = intel_init(sdw);
	if (ret) {
		dev_err(dev, "%s failed: %d\n", __func__, ret);
		return ret;
	}

	/*
	 * make sure all Slaves are tagged as UNATTACHED and provide
	 * reason for reinitialization
	 */
	sdw_clear_slave_status(bus, SDW_UNATTACH_REQUEST_MASTER_RESET);

	ret = sdw_cdns_enable_interrupt(cdns, true);
	if (ret < 0) {
		dev_err(dev, "cannot enable interrupts during resume\n");
		return ret;
	}

	/*
	 * follow recommended programming flows to avoid timeouts when
	 * gsync is enabled
	 */
	if (multi_link)
		intel_shim_sync_arm(sdw);

	ret = sdw_cdns_init(&sdw->cdns);
	if (ret < 0) {
		dev_err(dev, "unable to initialize Cadence IP during resume\n");
		return ret;
	}

	ret = sdw_cdns_exit_reset(cdns);
	if (ret < 0) {
		dev_err(dev, "unable to exit bus reset sequence during resume\n");
		return ret;
	}

	if (multi_link) {
		ret = intel_shim_sync_go(sdw);
		if (ret < 0) {
			dev_err(dev, "sync go failed during resume\n");
			return ret;
		}
	}
	sdw_cdns_check_self_clearing_bits(cdns, __func__,
					  true, INTEL_MASTER_RESET_ITERATIONS);

	/*
	 * after system resume, the pm_runtime suspend() may kick in
	 * during the enumeration, before any children device force the
	 * master device to remain active.  Using pm_runtime_get()
	 * routines is not really possible, since it'd prevent the
	 * master from suspending.
	 * A reasonable compromise is to update the pm_runtime
	 * counters and delay the pm_runtime suspend by several
	 * seconds, by when all enumeration should be complete.
	 */
	pm_runtime_mark_last_busy(dev);

	return ret;
}