static int scmi_probe()

in arm_scmi/driver.c [1805:1909]

• 77 lines of code
• 13 McCabe index (conditional complexity)

static int scmi_probe(struct platform_device *pdev)
{
	int ret;
	struct scmi_handle *handle;
	const struct scmi_desc *desc;
	struct scmi_info *info;
	struct device *dev = &pdev->dev;
	struct device_node *child, *np = dev->of_node;

	desc = of_device_get_match_data(dev);
	if (!desc)
		return -EINVAL;

	info = devm_kzalloc(dev, sizeof(*info), GFP_KERNEL);
	if (!info)
		return -ENOMEM;

	info->dev = dev;
	info->desc = desc;
	INIT_LIST_HEAD(&info->node);
	idr_init(&info->protocols);
	mutex_init(&info->protocols_mtx);
	idr_init(&info->active_protocols);

	platform_set_drvdata(pdev, info);
	idr_init(&info->tx_idr);
	idr_init(&info->rx_idr);

	handle = &info->handle;
	handle->dev = info->dev;
	handle->version = &info->version;
	handle->devm_protocol_get = scmi_devm_protocol_get;
	handle->devm_protocol_put = scmi_devm_protocol_put;

	if (desc->ops->link_supplier) {
		ret = desc->ops->link_supplier(dev);
		if (ret)
			return ret;
	}

	ret = scmi_txrx_setup(info, dev, SCMI_PROTOCOL_BASE);
	if (ret)
		return ret;

	ret = scmi_xfer_info_init(info);
	if (ret)
		goto clear_txrx_setup;

	if (scmi_notification_init(handle))
		dev_err(dev, "SCMI Notifications NOT available.\n");

	/*
	 * Trigger SCMI Base protocol initialization.
	 * It's mandatory and won't be ever released/deinit until the
	 * SCMI stack is shutdown/unloaded as a whole.
	 */
	ret = scmi_protocol_acquire(handle, SCMI_PROTOCOL_BASE);
	if (ret) {
		dev_err(dev, "unable to communicate with SCMI\n");
		goto notification_exit;
	}

	mutex_lock(&scmi_list_mutex);
	list_add_tail(&info->node, &scmi_list);
	mutex_unlock(&scmi_list_mutex);

	for_each_available_child_of_node(np, child) {
		u32 prot_id;

		if (of_property_read_u32(child, "reg", &prot_id))
			continue;

		if (!FIELD_FIT(MSG_PROTOCOL_ID_MASK, prot_id))
			dev_err(dev, "Out of range protocol %d\n", prot_id);

		if (!scmi_is_protocol_implemented(handle, prot_id)) {
			dev_err(dev, "SCMI protocol %d not implemented\n",
				prot_id);
			continue;
		}

		/*
		 * Save this valid DT protocol descriptor amongst
		 * @active_protocols for this SCMI instance/
		 */
		ret = idr_alloc(&info->active_protocols, child,
				prot_id, prot_id + 1, GFP_KERNEL);
		if (ret != prot_id) {
			dev_err(dev, "SCMI protocol %d already activated. Skip\n",
				prot_id);
			continue;
		}

		of_node_get(child);
		scmi_create_protocol_devices(child, info, prot_id);
	}

	return 0;

notification_exit:
	scmi_notification_exit(&info->handle);
clear_txrx_setup:
	scmi_cleanup_txrx_channels(info);
	return ret;
}