static int sbefifo_probe()

in fsi-sbefifo.c [950:1022]

• 54 lines of code
• 8 McCabe index (conditional complexity)

static int sbefifo_probe(struct device *dev)
{
	struct fsi_device *fsi_dev = to_fsi_dev(dev);
	struct sbefifo *sbefifo;
	struct device_node *np;
	struct platform_device *child;
	char child_name[32];
	int rc, didx, child_idx = 0;

	dev_dbg(dev, "Found sbefifo device\n");

	sbefifo = kzalloc(sizeof(*sbefifo), GFP_KERNEL);
	if (!sbefifo)
		return -ENOMEM;

	/* Grab a reference to the device (parent of our cdev), we'll drop it later */
	if (!get_device(dev)) {
		kfree(sbefifo);
		return -ENODEV;
	}

	sbefifo->magic = SBEFIFO_MAGIC;
	sbefifo->fsi_dev = fsi_dev;
	dev_set_drvdata(dev, sbefifo);
	mutex_init(&sbefifo->lock);

	/*
	 * Try cleaning up the FIFO. If this fails, we still register the
	 * driver and will try cleaning things up again on the next access.
	 */
	rc = sbefifo_cleanup_hw(sbefifo);
	if (rc && rc != -ESHUTDOWN)
		dev_err(dev, "Initial HW cleanup failed, will retry later\n");

	/* Create chardev for userspace access */
	sbefifo->dev.type = &fsi_cdev_type;
	sbefifo->dev.parent = dev;
	sbefifo->dev.release = sbefifo_free;
	device_initialize(&sbefifo->dev);

	/* Allocate a minor in the FSI space */
	rc = fsi_get_new_minor(fsi_dev, fsi_dev_sbefifo, &sbefifo->dev.devt, &didx);
	if (rc)
		goto err;

	dev_set_name(&sbefifo->dev, "sbefifo%d", didx);
	cdev_init(&sbefifo->cdev, &sbefifo_fops);
	rc = cdev_device_add(&sbefifo->cdev, &sbefifo->dev);
	if (rc) {
		dev_err(dev, "Error %d creating char device %s\n",
			rc, dev_name(&sbefifo->dev));
		goto err_free_minor;
	}

	/* Create platform devs for dts child nodes (occ, etc) */
	for_each_available_child_of_node(dev->of_node, np) {
		snprintf(child_name, sizeof(child_name), "%s-dev%d",
			 dev_name(&sbefifo->dev), child_idx++);
		child = of_platform_device_create(np, child_name, dev);
		if (!child)
			dev_warn(dev, "failed to create child %s dev\n",
				 child_name);
	}

	device_create_file(&sbefifo->dev, &dev_attr_timeout);

	return 0;
 err_free_minor:
	fsi_free_minor(sbefifo->dev.devt);
 err:
	put_device(&sbefifo->dev);
	return rc;
}