static int hub_master_probe()

in fsi-master-hub.c [195:260]

• 47 lines of code
• 5 McCabe index (conditional complexity)

static int hub_master_probe(struct device *dev)
{
	struct fsi_device *fsi_dev = to_fsi_dev(dev);
	struct fsi_master_hub *hub;
	uint32_t reg, links;
	__be32 __reg;
	int rc;

	rc = fsi_device_read(fsi_dev, FSI_MVER, &__reg, sizeof(__reg));
	if (rc)
		return rc;

	reg = be32_to_cpu(__reg);
	links = (reg >> 8) & 0xff;
	dev_dbg(dev, "hub version %08x (%d links)\n", reg, links);

	rc = fsi_slave_claim_range(fsi_dev->slave, FSI_HUB_LINK_OFFSET,
			FSI_HUB_LINK_SIZE * links);
	if (rc) {
		dev_err(dev, "can't claim slave address range for links");
		return rc;
	}

	hub = kzalloc(sizeof(*hub), GFP_KERNEL);
	if (!hub) {
		rc = -ENOMEM;
		goto err_release;
	}

	hub->addr = FSI_HUB_LINK_OFFSET;
	hub->size = FSI_HUB_LINK_SIZE * links;
	hub->upstream = fsi_dev;

	hub->master.dev.parent = dev;
	hub->master.dev.release = hub_master_release;
	hub->master.dev.of_node = of_node_get(dev_of_node(dev));

	hub->master.n_links = links;
	hub->master.read = hub_master_read;
	hub->master.write = hub_master_write;
	hub->master.send_break = hub_master_break;
	hub->master.link_enable = hub_master_link_enable;

	dev_set_drvdata(dev, hub);

	hub_master_init(hub);

	rc = fsi_master_register(&hub->master);
	if (rc)
		goto err_release;

	/* At this point, fsi_master_register performs the device_initialize(),
	 * and holds the sole reference on master.dev. This means the device
	 * will be freed (via ->release) during any subsequent call to
	 * fsi_master_unregister.  We add our own reference to it here, so we
	 * can perform cleanup (in _remove()) without it being freed before
	 * we're ready.
	 */
	get_device(&hub->master.dev);
	return 0;

err_release:
	fsi_slave_release_range(fsi_dev->slave, FSI_HUB_LINK_OFFSET,
			FSI_HUB_LINK_SIZE * links);
	return rc;
}