static int port100_probe()

in port100.c [1489:1620]

• 106 lines of code
• 17 McCabe index (conditional complexity)

static int port100_probe(struct usb_interface *interface,
			 const struct usb_device_id *id)
{
	struct port100 *dev;
	int rc;
	struct usb_host_interface *iface_desc;
	struct usb_endpoint_descriptor *endpoint;
	int in_endpoint;
	int out_endpoint;
	u16 fw_version;
	u64 cmd_type_mask;
	int i;

	dev = devm_kzalloc(&interface->dev, sizeof(struct port100), GFP_KERNEL);
	if (!dev)
		return -ENOMEM;

	mutex_init(&dev->out_urb_lock);
	dev->udev = usb_get_dev(interface_to_usbdev(interface));
	dev->interface = interface;
	usb_set_intfdata(interface, dev);

	in_endpoint = out_endpoint = 0;
	iface_desc = interface->cur_altsetting;
	for (i = 0; i < iface_desc->desc.bNumEndpoints; ++i) {
		endpoint = &iface_desc->endpoint[i].desc;

		if (!in_endpoint && usb_endpoint_is_bulk_in(endpoint))
			in_endpoint = endpoint->bEndpointAddress;

		if (!out_endpoint && usb_endpoint_is_bulk_out(endpoint))
			out_endpoint = endpoint->bEndpointAddress;
	}

	if (!in_endpoint || !out_endpoint) {
		nfc_err(&interface->dev,
			"Could not find bulk-in or bulk-out endpoint\n");
		rc = -ENODEV;
		goto error;
	}

	dev->in_urb = usb_alloc_urb(0, GFP_KERNEL);
	dev->out_urb = usb_alloc_urb(0, GFP_KERNEL);

	if (!dev->in_urb || !dev->out_urb) {
		nfc_err(&interface->dev, "Could not allocate USB URBs\n");
		rc = -ENOMEM;
		goto error;
	}

	usb_fill_bulk_urb(dev->in_urb, dev->udev,
			  usb_rcvbulkpipe(dev->udev, in_endpoint),
			  NULL, 0, NULL, dev);
	usb_fill_bulk_urb(dev->out_urb, dev->udev,
			  usb_sndbulkpipe(dev->udev, out_endpoint),
			  NULL, 0, port100_send_complete, dev);
	dev->out_urb->transfer_flags = URB_ZERO_PACKET;

	dev->skb_headroom = PORT100_FRAME_HEADER_LEN +
			    PORT100_COMM_RF_HEAD_MAX_LEN;
	dev->skb_tailroom = PORT100_FRAME_TAIL_LEN;

	init_completion(&dev->cmd_cancel_done);
	INIT_WORK(&dev->cmd_complete_work, port100_wq_cmd_complete);

	/* The first thing to do with the Port-100 is to set the command type
	 * to be used. If supported we use command type 1. 0 otherwise.
	 */
	cmd_type_mask = port100_get_command_type_mask(dev);
	if (!cmd_type_mask) {
		nfc_err(&interface->dev,
			"Could not get supported command types\n");
		rc = -ENODEV;
		goto error;
	}

	if (PORT100_CMD_TYPE_IS_SUPPORTED(cmd_type_mask, PORT100_CMD_TYPE_1))
		dev->cmd_type = PORT100_CMD_TYPE_1;
	else
		dev->cmd_type = PORT100_CMD_TYPE_0;

	rc = port100_set_command_type(dev, dev->cmd_type);
	if (rc) {
		nfc_err(&interface->dev,
			"The device does not support command type %u\n",
			dev->cmd_type);
		goto error;
	}

	fw_version = port100_get_firmware_version(dev);
	if (!fw_version)
		nfc_err(&interface->dev,
			"Could not get device firmware version\n");

	nfc_info(&interface->dev,
		 "Sony NFC Port-100 Series attached (firmware v%x.%02x)\n",
		 (fw_version & 0xFF00) >> 8, fw_version & 0xFF);

	dev->nfc_digital_dev = nfc_digital_allocate_device(&port100_digital_ops,
							   PORT100_PROTOCOLS,
							   PORT100_CAPABILITIES,
							   dev->skb_headroom,
							   dev->skb_tailroom);
	if (!dev->nfc_digital_dev) {
		nfc_err(&interface->dev,
			"Could not allocate nfc_digital_dev\n");
		rc = -ENOMEM;
		goto error;
	}

	nfc_digital_set_parent_dev(dev->nfc_digital_dev, &interface->dev);
	nfc_digital_set_drvdata(dev->nfc_digital_dev, dev);

	rc = nfc_digital_register_device(dev->nfc_digital_dev);
	if (rc) {
		nfc_err(&interface->dev,
			"Could not register digital device\n");
		goto free_nfc_dev;
	}

	return 0;

free_nfc_dev:
	nfc_digital_free_device(dev->nfc_digital_dev);

error:
	usb_free_urb(dev->in_urb);
	usb_free_urb(dev->out_urb);
	usb_put_dev(dev->udev);

	return rc;
}