static int s3cmci_probe()

in host/s3cmci.c [1508:1689]

• 141 lines of code
• 20 McCabe index (conditional complexity)

static int s3cmci_probe(struct platform_device *pdev)
{
	struct s3cmci_host *host;
	struct mmc_host	*mmc;
	int ret;

	mmc = mmc_alloc_host(sizeof(struct s3cmci_host), &pdev->dev);
	if (!mmc) {
		ret = -ENOMEM;
		goto probe_out;
	}

	host = mmc_priv(mmc);
	host->mmc 	= mmc;
	host->pdev	= pdev;

	if (pdev->dev.of_node)
		ret = s3cmci_probe_dt(host);
	else
		ret = s3cmci_probe_pdata(host);

	if (ret)
		goto probe_free_host;

	host->pdata = pdev->dev.platform_data;

	spin_lock_init(&host->complete_lock);
	tasklet_setup(&host->pio_tasklet, pio_tasklet);

	if (host->is2440) {
		host->sdiimsk	= S3C2440_SDIIMSK;
		host->sdidata	= S3C2440_SDIDATA;
		host->clk_div	= 1;
	} else {
		host->sdiimsk	= S3C2410_SDIIMSK;
		host->sdidata	= S3C2410_SDIDATA;
		host->clk_div	= 2;
	}

	host->complete_what 	= COMPLETION_NONE;
	host->pio_active 	= XFER_NONE;

	host->mem = platform_get_resource(pdev, IORESOURCE_MEM, 0);
	if (!host->mem) {
		dev_err(&pdev->dev,
			"failed to get io memory region resource.\n");

		ret = -ENOENT;
		goto probe_free_host;
	}

	host->mem = request_mem_region(host->mem->start,
				       resource_size(host->mem), pdev->name);

	if (!host->mem) {
		dev_err(&pdev->dev, "failed to request io memory region.\n");
		ret = -ENOENT;
		goto probe_free_host;
	}

	host->base = ioremap(host->mem->start, resource_size(host->mem));
	if (!host->base) {
		dev_err(&pdev->dev, "failed to ioremap() io memory region.\n");
		ret = -EINVAL;
		goto probe_free_mem_region;
	}

	host->irq = platform_get_irq(pdev, 0);
	if (host->irq <= 0) {
		ret = -EINVAL;
		goto probe_iounmap;
	}

	if (request_irq(host->irq, s3cmci_irq, IRQF_NO_AUTOEN, DRIVER_NAME, host)) {
		dev_err(&pdev->dev, "failed to request mci interrupt.\n");
		ret = -ENOENT;
		goto probe_iounmap;
	}

	host->irq_state = false;

	/* Depending on the dma state, get a DMA channel to use. */

	if (s3cmci_host_usedma(host)) {
		host->dma = dma_request_chan(&pdev->dev, "rx-tx");
		ret = PTR_ERR_OR_ZERO(host->dma);
		if (ret) {
			dev_err(&pdev->dev, "cannot get DMA channel.\n");
			goto probe_free_irq;
		}
	}

	host->clk = clk_get(&pdev->dev, "sdi");
	if (IS_ERR(host->clk)) {
		dev_err(&pdev->dev, "failed to find clock source.\n");
		ret = PTR_ERR(host->clk);
		host->clk = NULL;
		goto probe_free_dma;
	}

	ret = clk_prepare_enable(host->clk);
	if (ret) {
		dev_err(&pdev->dev, "failed to enable clock source.\n");
		goto clk_free;
	}

	host->clk_rate = clk_get_rate(host->clk);

	mmc->ops 	= &s3cmci_ops;
	mmc->ocr_avail	= MMC_VDD_32_33 | MMC_VDD_33_34;
#ifdef CONFIG_MMC_S3C_HW_SDIO_IRQ
	mmc->caps	= MMC_CAP_4_BIT_DATA | MMC_CAP_SDIO_IRQ;
#else
	mmc->caps	= MMC_CAP_4_BIT_DATA;
#endif
	mmc->f_min 	= host->clk_rate / (host->clk_div * 256);
	mmc->f_max 	= host->clk_rate / host->clk_div;

	if (host->pdata->ocr_avail)
		mmc->ocr_avail = host->pdata->ocr_avail;

	mmc->max_blk_count	= 4095;
	mmc->max_blk_size	= 4095;
	mmc->max_req_size	= 4095 * 512;
	mmc->max_seg_size	= mmc->max_req_size;

	mmc->max_segs		= 128;

	dbg(host, dbg_debug,
	    "probe: mode:%s mapped mci_base:%p irq:%u irq_cd:%u dma:%p.\n",
	    (host->is2440?"2440":""),
	    host->base, host->irq, host->irq_cd, host->dma);

	ret = s3cmci_cpufreq_register(host);
	if (ret) {
		dev_err(&pdev->dev, "failed to register cpufreq\n");
		goto free_dmabuf;
	}

	ret = mmc_add_host(mmc);
	if (ret) {
		dev_err(&pdev->dev, "failed to add mmc host.\n");
		goto free_cpufreq;
	}

	s3cmci_debugfs_attach(host);

	platform_set_drvdata(pdev, mmc);
	dev_info(&pdev->dev, "%s - using %s, %s SDIO IRQ\n", mmc_hostname(mmc),
		 s3cmci_host_usedma(host) ? "dma" : "pio",
		 mmc->caps & MMC_CAP_SDIO_IRQ ? "hw" : "sw");

	return 0;

 free_cpufreq:
	s3cmci_cpufreq_deregister(host);

 free_dmabuf:
	clk_disable_unprepare(host->clk);

 clk_free:
	clk_put(host->clk);

 probe_free_dma:
	if (s3cmci_host_usedma(host))
		dma_release_channel(host->dma);

 probe_free_irq:
	free_irq(host->irq, host);

 probe_iounmap:
	iounmap(host->base);

 probe_free_mem_region:
	release_mem_region(host->mem->start, resource_size(host->mem));

 probe_free_host:
	mmc_free_host(mmc);

 probe_out:
	return ret;
}