static int spi_imx_probe()

in spi-imx.c [1592:1764]


static int spi_imx_probe(struct platform_device *pdev)
{
	struct device_node *np = pdev->dev.of_node;
	struct spi_master *master;
	struct spi_imx_data *spi_imx;
	struct resource *res;
	int ret, irq, spi_drctl;
	const struct spi_imx_devtype_data *devtype_data =
			of_device_get_match_data(&pdev->dev);
	bool slave_mode;
	u32 val;

	slave_mode = devtype_data->has_slavemode &&
			of_property_read_bool(np, "spi-slave");
	if (slave_mode)
		master = spi_alloc_slave(&pdev->dev,
					 sizeof(struct spi_imx_data));
	else
		master = spi_alloc_master(&pdev->dev,
					  sizeof(struct spi_imx_data));
	if (!master)
		return -ENOMEM;

	ret = of_property_read_u32(np, "fsl,spi-rdy-drctl", &spi_drctl);
	if ((ret < 0) || (spi_drctl >= 0x3)) {
		/* '11' is reserved */
		spi_drctl = 0;
	}

	platform_set_drvdata(pdev, master);

	master->bits_per_word_mask = SPI_BPW_RANGE_MASK(1, 32);
	master->bus_num = np ? -1 : pdev->id;
	master->use_gpio_descriptors = true;

	spi_imx = spi_master_get_devdata(master);
	spi_imx->bitbang.master = master;
	spi_imx->dev = &pdev->dev;
	spi_imx->slave_mode = slave_mode;

	spi_imx->devtype_data = devtype_data;

	/*
	 * Get number of chip selects from device properties. This can be
	 * coming from device tree or boardfiles, if it is not defined,
	 * a default value of 3 chip selects will be used, as all the legacy
	 * board files have <= 3 chip selects.
	 */
	if (!device_property_read_u32(&pdev->dev, "num-cs", &val))
		master->num_chipselect = val;
	else
		master->num_chipselect = 3;

	spi_imx->bitbang.setup_transfer = spi_imx_setupxfer;
	spi_imx->bitbang.txrx_bufs = spi_imx_transfer;
	spi_imx->bitbang.master->setup = spi_imx_setup;
	spi_imx->bitbang.master->cleanup = spi_imx_cleanup;
	spi_imx->bitbang.master->prepare_message = spi_imx_prepare_message;
	spi_imx->bitbang.master->unprepare_message = spi_imx_unprepare_message;
	spi_imx->bitbang.master->slave_abort = spi_imx_slave_abort;
	spi_imx->bitbang.master->mode_bits = SPI_CPOL | SPI_CPHA | SPI_CS_HIGH \
					     | SPI_NO_CS;
	if (is_imx35_cspi(spi_imx) || is_imx51_ecspi(spi_imx) ||
	    is_imx53_ecspi(spi_imx))
		spi_imx->bitbang.master->mode_bits |= SPI_LOOP | SPI_READY;

	if (is_imx51_ecspi(spi_imx) &&
	    device_property_read_u32(&pdev->dev, "cs-gpios", NULL))
		/*
		 * When using HW-CS implementing SPI_CS_WORD can be done by just
		 * setting the burst length to the word size. This is
		 * considerably faster than manually controlling the CS.
		 */
		spi_imx->bitbang.master->mode_bits |= SPI_CS_WORD;

	spi_imx->spi_drctl = spi_drctl;

	init_completion(&spi_imx->xfer_done);

	res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
	spi_imx->base = devm_ioremap_resource(&pdev->dev, res);
	if (IS_ERR(spi_imx->base)) {
		ret = PTR_ERR(spi_imx->base);
		goto out_master_put;
	}
	spi_imx->base_phys = res->start;

	irq = platform_get_irq(pdev, 0);
	if (irq < 0) {
		ret = irq;
		goto out_master_put;
	}

	ret = devm_request_irq(&pdev->dev, irq, spi_imx_isr, 0,
			       dev_name(&pdev->dev), spi_imx);
	if (ret) {
		dev_err(&pdev->dev, "can't get irq%d: %d\n", irq, ret);
		goto out_master_put;
	}

	spi_imx->clk_ipg = devm_clk_get(&pdev->dev, "ipg");
	if (IS_ERR(spi_imx->clk_ipg)) {
		ret = PTR_ERR(spi_imx->clk_ipg);
		goto out_master_put;
	}

	spi_imx->clk_per = devm_clk_get(&pdev->dev, "per");
	if (IS_ERR(spi_imx->clk_per)) {
		ret = PTR_ERR(spi_imx->clk_per);
		goto out_master_put;
	}

	ret = clk_prepare_enable(spi_imx->clk_per);
	if (ret)
		goto out_master_put;

	ret = clk_prepare_enable(spi_imx->clk_ipg);
	if (ret)
		goto out_put_per;

	pm_runtime_set_autosuspend_delay(spi_imx->dev, MXC_RPM_TIMEOUT);
	pm_runtime_use_autosuspend(spi_imx->dev);
	pm_runtime_get_noresume(spi_imx->dev);
	pm_runtime_set_active(spi_imx->dev);
	pm_runtime_enable(spi_imx->dev);

	spi_imx->spi_clk = clk_get_rate(spi_imx->clk_per);
	/*
	 * Only validated on i.mx35 and i.mx6 now, can remove the constraint
	 * if validated on other chips.
	 */
	if (spi_imx->devtype_data->has_dmamode) {
		ret = spi_imx_sdma_init(&pdev->dev, spi_imx, master);
		if (ret == -EPROBE_DEFER)
			goto out_runtime_pm_put;

		if (ret < 0)
			dev_dbg(&pdev->dev, "dma setup error %d, use pio\n",
				ret);
	}

	spi_imx->devtype_data->reset(spi_imx);

	spi_imx->devtype_data->intctrl(spi_imx, 0);

	master->dev.of_node = pdev->dev.of_node;
	ret = spi_bitbang_start(&spi_imx->bitbang);
	if (ret) {
		dev_err_probe(&pdev->dev, ret, "bitbang start failed\n");
		goto out_bitbang_start;
	}

	pm_runtime_mark_last_busy(spi_imx->dev);
	pm_runtime_put_autosuspend(spi_imx->dev);

	return ret;

out_bitbang_start:
	if (spi_imx->devtype_data->has_dmamode)
		spi_imx_sdma_exit(spi_imx);
out_runtime_pm_put:
	pm_runtime_dont_use_autosuspend(spi_imx->dev);
	pm_runtime_set_suspended(&pdev->dev);
	pm_runtime_disable(spi_imx->dev);

	clk_disable_unprepare(spi_imx->clk_ipg);
out_put_per:
	clk_disable_unprepare(spi_imx->clk_per);
out_master_put:
	spi_master_put(master);

	return ret;
}