static int ti_sci_probe()

in ti_sci.c [3294:3436]

• 115 lines of code
• 18 McCabe index (conditional complexity)

static int ti_sci_probe(struct platform_device *pdev)
{
	struct device *dev = &pdev->dev;
	const struct of_device_id *of_id;
	const struct ti_sci_desc *desc;
	struct ti_sci_xfer *xfer;
	struct ti_sci_info *info = NULL;
	struct ti_sci_xfers_info *minfo;
	struct mbox_client *cl;
	int ret = -EINVAL;
	int i;
	int reboot = 0;
	u32 h_id;

	of_id = of_match_device(ti_sci_of_match, dev);
	if (!of_id) {
		dev_err(dev, "OF data missing\n");
		return -EINVAL;
	}
	desc = of_id->data;

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

	info->dev = dev;
	info->desc = desc;
	ret = of_property_read_u32(dev->of_node, "ti,host-id", &h_id);
	/* if the property is not present in DT, use a default from desc */
	if (ret < 0) {
		info->host_id = info->desc->default_host_id;
	} else {
		if (!h_id) {
			dev_warn(dev, "Host ID 0 is reserved for firmware\n");
			info->host_id = info->desc->default_host_id;
		} else {
			info->host_id = h_id;
		}
	}

	reboot = of_property_read_bool(dev->of_node,
				       "ti,system-reboot-controller");
	INIT_LIST_HEAD(&info->node);
	minfo = &info->minfo;

	/*
	 * Pre-allocate messages
	 * NEVER allocate more than what we can indicate in hdr.seq
	 * if we have data description bug, force a fix..
	 */
	if (WARN_ON(desc->max_msgs >=
		    1 << 8 * sizeof(((struct ti_sci_msg_hdr *)0)->seq)))
		return -EINVAL;

	minfo->xfer_block = devm_kcalloc(dev,
					 desc->max_msgs,
					 sizeof(*minfo->xfer_block),
					 GFP_KERNEL);
	if (!minfo->xfer_block)
		return -ENOMEM;

	minfo->xfer_alloc_table = devm_kcalloc(dev,
					       BITS_TO_LONGS(desc->max_msgs),
					       sizeof(unsigned long),
					       GFP_KERNEL);
	if (!minfo->xfer_alloc_table)
		return -ENOMEM;
	bitmap_zero(minfo->xfer_alloc_table, desc->max_msgs);

	/* Pre-initialize the buffer pointer to pre-allocated buffers */
	for (i = 0, xfer = minfo->xfer_block; i < desc->max_msgs; i++, xfer++) {
		xfer->xfer_buf = devm_kcalloc(dev, 1, desc->max_msg_size,
					      GFP_KERNEL);
		if (!xfer->xfer_buf)
			return -ENOMEM;

		xfer->tx_message.buf = xfer->xfer_buf;
		init_completion(&xfer->done);
	}

	ret = ti_sci_debugfs_create(pdev, info);
	if (ret)
		dev_warn(dev, "Failed to create debug file\n");

	platform_set_drvdata(pdev, info);

	cl = &info->cl;
	cl->dev = dev;
	cl->tx_block = false;
	cl->rx_callback = ti_sci_rx_callback;
	cl->knows_txdone = true;

	spin_lock_init(&minfo->xfer_lock);
	sema_init(&minfo->sem_xfer_count, desc->max_msgs);

	info->chan_rx = mbox_request_channel_byname(cl, "rx");
	if (IS_ERR(info->chan_rx)) {
		ret = PTR_ERR(info->chan_rx);
		goto out;
	}

	info->chan_tx = mbox_request_channel_byname(cl, "tx");
	if (IS_ERR(info->chan_tx)) {
		ret = PTR_ERR(info->chan_tx);
		goto out;
	}
	ret = ti_sci_cmd_get_revision(info);
	if (ret) {
		dev_err(dev, "Unable to communicate with TISCI(%d)\n", ret);
		goto out;
	}

	ti_sci_setup_ops(info);

	if (reboot) {
		info->nb.notifier_call = tisci_reboot_handler;
		info->nb.priority = 128;

		ret = register_restart_handler(&info->nb);
		if (ret) {
			dev_err(dev, "reboot registration fail(%d)\n", ret);
			return ret;
		}
	}

	dev_info(dev, "ABI: %d.%d (firmware rev 0x%04x '%s')\n",
		 info->handle.version.abi_major, info->handle.version.abi_minor,
		 info->handle.version.firmware_revision,
		 info->handle.version.firmware_description);

	mutex_lock(&ti_sci_list_mutex);
	list_add_tail(&info->node, &ti_sci_list);
	mutex_unlock(&ti_sci_list_mutex);

	return of_platform_populate(dev->of_node, NULL, NULL, dev);
out:
	if (!IS_ERR(info->chan_tx))
		mbox_free_channel(info->chan_tx);
	if (!IS_ERR(info->chan_rx))
		mbox_free_channel(info->chan_rx);
	debugfs_remove(info->d);
	return ret;
}