static int rio_enum_mport()

in rio-scan.c [942:1011]

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

static int rio_enum_mport(struct rio_mport *mport, u32 flags)
{
	struct rio_net *net = NULL;
	int rc = 0;

	printk(KERN_INFO "RIO: enumerate master port %d, %s\n", mport->id,
	       mport->name);

	/*
	 * To avoid multiple start requests (repeat enumeration is not supported
	 * by this method) check if enumeration/discovery was performed for this
	 * mport: if mport was added into the list of mports for a net exit
	 * with error.
	 */
	if (mport->nnode.next || mport->nnode.prev)
		return -EBUSY;

	/* If somebody else enumerated our master port device, bail. */
	if (rio_enum_host(mport) < 0) {
		printk(KERN_INFO
		       "RIO: master port %d device has been enumerated by a remote host\n",
		       mport->id);
		rc = -EBUSY;
		goto out;
	}

	/* If master port has an active link, allocate net and enum peers */
	if (rio_mport_is_active(mport)) {
		net = rio_scan_alloc_net(mport, 1, 0);
		if (!net) {
			printk(KERN_ERR "RIO: failed to allocate new net\n");
			rc = -ENOMEM;
			goto out;
		}

		/* reserve mport destID in new net */
		rio_destid_reserve(net, mport->host_deviceid);

		/* Enable Input Output Port (transmitter receiver) */
		rio_enable_rx_tx_port(mport, 1, 0, 0, 0);

		/* Set component tag for host */
		rio_local_write_config_32(mport, RIO_COMPONENT_TAG_CSR,
					  next_comptag++);

		next_destid = rio_destid_alloc(net);

		if (rio_enum_peer(net, mport, 0, NULL, 0) < 0) {
			/* A higher priority host won enumeration, bail. */
			printk(KERN_INFO
			       "RIO: master port %d device has lost enumeration to a remote host\n",
			       mport->id);
			rio_clear_locks(net);
			rc = -EBUSY;
			goto out;
		}
		/* free the last allocated destID (unused) */
		rio_destid_free(net, next_destid);
		rio_update_route_tables(net);
		rio_clear_locks(net);
		rio_pw_enable(mport, 1);
	} else {
		printk(KERN_INFO "RIO: master port %d link inactive\n",
		       mport->id);
		rc = -EINVAL;
	}

      out:
	return rc;
}