static int nhi_probe()

in nhi.c [1180:1276]

• 74 lines of code
• 15 McCabe index (conditional complexity)

static int nhi_probe(struct pci_dev *pdev, const struct pci_device_id *id)
{
	struct tb_nhi *nhi;
	struct tb *tb;
	int res;

	if (!nhi_imr_valid(pdev)) {
		dev_warn(&pdev->dev, "firmware image not valid, aborting\n");
		return -ENODEV;
	}

	res = pcim_enable_device(pdev);
	if (res) {
		dev_err(&pdev->dev, "cannot enable PCI device, aborting\n");
		return res;
	}

	res = pcim_iomap_regions(pdev, 1 << 0, "thunderbolt");
	if (res) {
		dev_err(&pdev->dev, "cannot obtain PCI resources, aborting\n");
		return res;
	}

	nhi = devm_kzalloc(&pdev->dev, sizeof(*nhi), GFP_KERNEL);
	if (!nhi)
		return -ENOMEM;

	nhi->pdev = pdev;
	nhi->ops = (const struct tb_nhi_ops *)id->driver_data;
	/* cannot fail - table is allocated bin pcim_iomap_regions */
	nhi->iobase = pcim_iomap_table(pdev)[0];
	nhi->hop_count = ioread32(nhi->iobase + REG_HOP_COUNT) & 0x3ff;
	dev_dbg(&pdev->dev, "total paths: %d\n", nhi->hop_count);

	nhi->tx_rings = devm_kcalloc(&pdev->dev, nhi->hop_count,
				     sizeof(*nhi->tx_rings), GFP_KERNEL);
	nhi->rx_rings = devm_kcalloc(&pdev->dev, nhi->hop_count,
				     sizeof(*nhi->rx_rings), GFP_KERNEL);
	if (!nhi->tx_rings || !nhi->rx_rings)
		return -ENOMEM;

	nhi_check_quirks(nhi);

	res = nhi_init_msi(nhi);
	if (res) {
		dev_err(&pdev->dev, "cannot enable MSI, aborting\n");
		return res;
	}

	spin_lock_init(&nhi->lock);

	res = dma_set_mask_and_coherent(&pdev->dev, DMA_BIT_MASK(64));
	if (res)
		res = dma_set_mask_and_coherent(&pdev->dev, DMA_BIT_MASK(32));
	if (res) {
		dev_err(&pdev->dev, "failed to set DMA mask\n");
		return res;
	}

	pci_set_master(pdev);

	if (nhi->ops && nhi->ops->init) {
		res = nhi->ops->init(nhi);
		if (res)
			return res;
	}

	tb = nhi_select_cm(nhi);
	if (!tb) {
		dev_err(&nhi->pdev->dev,
			"failed to determine connection manager, aborting\n");
		return -ENODEV;
	}

	dev_dbg(&nhi->pdev->dev, "NHI initialized, starting thunderbolt\n");

	res = tb_domain_add(tb);
	if (res) {
		/*
		 * At this point the RX/TX rings might already have been
		 * activated. Do a proper shutdown.
		 */
		tb_domain_put(tb);
		nhi_shutdown(nhi);
		return res;
	}
	pci_set_drvdata(pdev, tb);

	device_wakeup_enable(&pdev->dev);

	pm_runtime_allow(&pdev->dev);
	pm_runtime_set_autosuspend_delay(&pdev->dev, TB_AUTOSUSPEND_DELAY);
	pm_runtime_use_autosuspend(&pdev->dev);
	pm_runtime_put_autosuspend(&pdev->dev);

	return 0;
}