static int sbp2_probe()

in sbp2.c [1122:1190]

• 45 lines of code
• 6 McCabe index (conditional complexity)

static int sbp2_probe(struct fw_unit *unit, const struct ieee1394_device_id *id)
{
	struct fw_device *device = fw_parent_device(unit);
	struct sbp2_target *tgt;
	struct sbp2_logical_unit *lu;
	struct Scsi_Host *shost;
	u32 model, firmware_revision;

	/* cannot (or should not) handle targets on the local node */
	if (device->is_local)
		return -ENODEV;

	shost = scsi_host_alloc(&scsi_driver_template, sizeof(*tgt));
	if (shost == NULL)
		return -ENOMEM;

	tgt = (struct sbp2_target *)shost->hostdata;
	dev_set_drvdata(&unit->device, tgt);
	tgt->unit = unit;
	INIT_LIST_HEAD(&tgt->lu_list);
	spin_lock_init(&tgt->lock);
	tgt->guid = (u64)device->config_rom[3] << 32 | device->config_rom[4];

	if (fw_device_enable_phys_dma(device) < 0)
		goto fail_shost_put;

	shost->max_cmd_len = SBP2_MAX_CDB_SIZE;

	if (scsi_add_host_with_dma(shost, &unit->device,
				   device->card->device) < 0)
		goto fail_shost_put;

	/* implicit directory ID */
	tgt->directory_id = ((unit->directory - device->config_rom) * 4
			     + CSR_CONFIG_ROM) & 0xffffff;

	firmware_revision = SBP2_ROM_VALUE_MISSING;
	model		  = SBP2_ROM_VALUE_MISSING;

	if (sbp2_scan_unit_dir(tgt, unit->directory, &model,
			       &firmware_revision) < 0)
		goto fail_remove;

	sbp2_clamp_management_orb_timeout(tgt);
	sbp2_init_workarounds(tgt, model, firmware_revision);

	/*
	 * At S100 we can do 512 bytes per packet, at S200 1024 bytes,
	 * and so on up to 4096 bytes.  The SBP-2 max_payload field
	 * specifies the max payload size as 2 ^ (max_payload + 2), so
	 * if we set this to max_speed + 7, we get the right value.
	 */
	tgt->max_payload = min3(device->max_speed + 7, 10U,
				device->card->max_receive - 1);

	/* Do the login in a workqueue so we can easily reschedule retries. */
	list_for_each_entry(lu, &tgt->lu_list, link)
		sbp2_queue_work(lu, DIV_ROUND_UP(HZ, 5));

	return 0;

 fail_remove:
	sbp2_remove(unit);
	return -ENOMEM;

 fail_shost_put:
	scsi_host_put(shost);
	return -ENOMEM;
}