Re: [PATCH v6 2/2] spi: cadence-quadpsi: Add support for the Cadence QSPI controller

From: Vignesh Raghavendra
Date: Wed Jan 08 2020 - 00:25:30 EST


Hi,
[...]
On 30/12/19 1:11 pm, Ramuthevar,Vadivel MuruganX wrote:
> +static int cqspi_probe(struct platform_device *pdev)
> +{
> + struct device *dev = &pdev->dev;
> + struct struct_cqspi *cqspi;
> + struct spi_master *master;
> + struct reset_control *rstc, *rstc_ocp;
> + const struct cqspi_driver_platdata *ddata;
> + struct cqspi_platform_data *pdata = NULL;
> + struct resource *res = NULL;
> + int ret;
> +
> + master = spi_alloc_master(&pdev->dev, sizeof(*cqspi));
> + if (!master) {
> + dev_err(&pdev->dev, "spi_alloc_master failed\n");
> + return -ENOMEM;
> + }
> + master->mode_bits = SPI_RX_QUAD | SPI_TX_DUAL | SPI_RX_DUAL |
> + SPI_RX_OCTAL;
> + master->setup = cqspi_setup;
> + master->mem_ops = &cqspi_mem_ops;
> + master->dev.of_node = pdev->dev.of_node;
> + cqspi = spi_master_get_devdata(master);
> + cqspi->pdev = pdev;
> +
> + pdata = devm_kmalloc(&pdev->dev, sizeof(*pdata), GFP_KERNEL);

devm_kzalloc()?

> + if (!pdata)
> + return -ENOMEM;
> +
> + pdev->dev.platform_data = pdata;
> +
> + /* Obtain QSPI clock. */
> + cqspi->clk = devm_clk_get(&pdev->dev, "qspi");

clock-name of "qspi" is not mandatory as per DT binding and current DT
files don't have clock-names property. This therefore cause probe to
fail. This should remain:

cqspi->clk = devm_clk_get(&pdev->dev, "NULL");

> + if (IS_ERR(cqspi->clk)) {
> + dev_err(&pdev->dev, "cannot get qspi clk\n");
> + return PTR_ERR(cqspi->clk);
> + }
> + pdata->master_ref_clk_hz = clk_get_rate(cqspi->clk);
> +
> + ret = clk_prepare_enable(cqspi->clk);
> + if (ret < 0) {
> + dev_err(&pdev->dev, "failed to enable qspi clock: %d\n", ret);
> + return ret;
> + }
> +
> + /* Obtain configuration from OF. */
> + ret = cqspi_of_get_pdata(pdev);
> + if (ret) {
> + dev_err(&pdev->dev, "Get platform data failed.\n");
> + return -ENODEV;
> + }
> +
> + cqspi->res = res;
> + /* Obtain and remap controller address. */
> + res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
> + cqspi->iobase = devm_ioremap_resource(&pdev->dev, res);
> + if (IS_ERR(cqspi->iobase)) {
> + dev_err(dev, "Cannot remap controller address.\n");
> + return PTR_ERR(cqspi->iobase);
> + }
> +
> + /* Obtain and remap AHB address. */
> + res = platform_get_resource(pdev, IORESOURCE_MEM, 1);
> + cqspi->qspi_ahb_virt = devm_ioremap_resource(dev, res);
> + if (IS_ERR(cqspi->qspi_ahb_virt)) {
> + dev_err(dev, "Cannot remap AHB address.\n");
> + return PTR_ERR(cqspi->qspi_ahb_virt);
> + }
> + cqspi->ahbbase = res;
> + cqspi->ahb_size = resource_size(res);
> +
> + /* Obtain QSPI reset control */
> + rstc = devm_reset_control_get_optional_exclusive(dev, "qspi");
> + if (IS_ERR(rstc)) {
> + dev_err(dev, "Cannot get QSPI reset.\n");
> + return PTR_ERR(rstc);
> + }
> +
> + rstc_ocp = devm_reset_control_get_optional_exclusive(dev, "qspi-ocp");
> + if (IS_ERR(rstc_ocp)) {
> + dev_err(dev, "Cannot get QSPI OCP reset.\n");
> + return PTR_ERR(rstc_ocp);
> + }
> +
> + reset_control_assert(rstc);
> + reset_control_deassert(rstc);
> +
> + reset_control_assert(rstc_ocp);
> + reset_control_deassert(rstc_ocp);
> +
> + ddata = of_device_get_match_data(dev);
> + if (ddata && (ddata->quirks & CQSPI_NEEDS_WR_DELAY))
> + cqspi->wr_delay = 5 * DIV_ROUND_UP(NSEC_PER_SEC,
> + pdata->master_ref_clk_hz);
> +
> + if (ddata && (ddata->quirks & CQSPI_DISABLE_DAC_MODE))
> + cqspi->use_dac_mode = false;
> +
> + init_completion(&cqspi->transfer_complete);
> +
> + /* Obtain IRQ line. */
> + cqspi->irq = platform_get_irq(pdev, 0);
> + if (cqspi->irq < 0) {
> + dev_err(dev, "platform_get_irq failed.\n");
> + ret = -ENXIO;
> + }
> + ret = devm_request_irq(dev, cqspi->irq, cqspi_irq_handler, 0,
> + pdev->name, cqspi);
> + if (ret) {
> + dev_err(dev, "request_irq failed.\n");
> + goto out_clk_disable;
> + }
> +
> + master->bus_num = pdata->bus_num;
> + master->num_chipselect = pdata->num_chipselect;

Where is pdata->bus_num and pdata->num_chipselect initialized? This
causes devm_spi_register_master() to fail randomly as num_chipselect may
be 0.

> + mutex_init(&cqspi->lock);
> + platform_set_drvdata(pdev, master);
> + cqspi_controller_init(cqspi);
> + cqspi->current_cs = -1;
> +
> + ret = devm_spi_register_master(dev, master);
> + if (ret) {
> + dev_err(&pdev->dev, "devm_spi_register_master failed.\n");
> + goto err_of;
> + }
> +
> + return 0;
> +
> +out_clk_disable:
> + clk_disable_unprepare(cqspi->clk);
> +err_of:
> + spi_master_put(master);
> + dev_err(&pdev->dev, "Cadence QSPI controller probe failed\n");
> + return ret;
> +}
> +

--
Regards
Vignesh