Re: [PATCH RFC v3] mmc: sdhci-msm: Add support for MSM chipsets

[Georgi Djakov <gdjakov@mm-sol.com>]

Hi Ivan,

On 08/23/2013 10:34 AM, Ivan T. Ivanov wrote:
> Hi Georgi,
>
> On Tue, 2013-08-20 at 19:44 +0300, Georgi Djakov wrote:
>> This platform driver adds the support of Secure Digital Host
>> Controller Interface compliant controller in MSM chipsets.
>>
>> CC: Asutosh Das <asutoshd@codeaurora.org>
>> CC: Venkat Gopalakrishnan <venkatg@codeaurora.org>
>> CC: Sahitya Tummala <stummala@codeaurora.org>
>> CC: Subhash Jadavani <subhashj@codeaurora.org>
>> Signed-off-by: Georgi Djakov <gdjakov@mm-sol.com>
>> ---
>> Changes from v2:
>> - Added DT bindings for clocks
>> - Moved voltage regulators data to platform data
>> - Removed unneeded includes
>> - Removed obsolete and wrapper functions
>> - Removed error checking where unnecessary
>> - Removed redundant _clk suffix from clock names
>> - Just return instead of goto where possible
>> - Minor fixes
>>
>
> Is this version intermediate step before you address
> all previous comments?
>
>
>> +
>> +static const struct of_device_id sdhci_msm_dt_match[] = {
>> +	{.compatible = "qcom,sdhci-msm"},
>
> Missing termination entry
>
>> +};
>> +
>> +MODULE_DEVICE_TABLE(of, sdhci_msm_dt_match);
>> +
>> +static int sdhci_msm_probe(struct platform_device *pdev)
>> +{
>> +	struct sdhci_host *host;
>> +	struct sdhci_pltfm_host *pltfm_host;
>> +	struct sdhci_msm_host *msm_host;
>> +	struct resource *core_memres = NULL;
>> +	int ret = 0, dead = 0;
>> +	struct pinctrl	*pinctrl;
>> +
>> +	msm_host = devm_kzalloc(&pdev->dev, sizeof(struct sdhci_msm_host),
>> +				GFP_KERNEL);
>> +	if (!msm_host)
>> +		return -ENOMEM;
>> +
>> +	host = sdhci_pltfm_init(pdev, &msm_host->sdhci_msm_pdata, 0);
>> +	if (IS_ERR(host)) {
>> +		dev_err(mmc_dev(host->mmc), "sdhci_pltfm_init error\n");
>> +		return PTR_ERR(host);
>> +	}
>> +
>> +	pltfm_host = sdhci_priv(host);
>> +	pltfm_host->priv = msm_host;
>> +	msm_host->mmc = host->mmc;
>> +	msm_host->pdev = pdev;
>> +
>> +	ret = mmc_of_parse(host->mmc);
>> +	if (ret)
>
> Shouldn't sdhci_pltfm_init operation be reverted?
>
>> +		return ret;
>> +
>> +	/* Extract platform data */
>> +	if (pdev->dev.of_node) {
>> +		msm_host->pdata = sdhci_msm_populate_pdata(&pdev->dev);
>> +		if (!msm_host->pdata) {
>> +			dev_err(&pdev->dev, "DT parsing error\n");
>> +			goto pltfm_free;
>> +		}
>> +	} else {
>> +		dev_err(&pdev->dev, "No device tree node\n");
>> +		goto pltfm_free;
>> +	}
>> +
>> +	/* Setup pins */
>> +	pinctrl = devm_pinctrl_get_select_default(&pdev->dev);
>> +	if (IS_ERR(pinctrl))
>> +		dev_warn(&pdev->dev, "pins are not configured by the driver\n");
>> +
>> +	/* Setup Clocks */
>> +
>> +	/* Setup SDCC bus voter clock. */
>> +	msm_host->bus_clk = devm_clk_get(&pdev->dev, "bus");
>> +	if (!IS_ERR_OR_NULL(msm_host->bus_clk)) {
>> +		/* Vote for max. clk rate for max. performance */
>> +		ret = clk_set_rate(msm_host->bus_clk, INT_MAX);
>> +		if (ret)
>> +			goto pltfm_free;
>> +		ret = clk_prepare_enable(msm_host->bus_clk);
>> +		if (ret)
>> +			goto pltfm_free;
>> +	}
>> +
>> +	/* Setup main peripheral bus clock */
>> +	msm_host->pclk = devm_clk_get(&pdev->dev, "iface");
>> +	if (!IS_ERR(msm_host->pclk)) {
>> +		ret = clk_prepare_enable(msm_host->pclk);
>> +		if (ret) {
>> +			dev_err(&pdev->dev,
>> +				"Main peripheral clock setup failed (%d)\n",
>> +				ret);
>> +			goto bus_clk_disable;
>> +		}
>> +	}
>> +
>> +	/* Setup SDC MMC clock */
>> +	msm_host->clk = devm_clk_get(&pdev->dev, "core");
>> +	if (IS_ERR(msm_host->clk)) {
>> +		ret = PTR_ERR(msm_host->clk);
>> +		dev_err(&pdev->dev, "SDC MMC clock setup failed (%d)\n", ret);
>> +		goto pclk_disable;
>> +	}
>> +
>> +	ret = clk_prepare_enable(msm_host->clk);
>> +	if (ret)
>> +		goto pclk_disable;
>> +
>> +	/* Setup regulators */
>> +	ret = sdhci_msm_vreg_init(&pdev->dev, msm_host->pdata, true);
>> +	if (ret) {
>> +		dev_err(&pdev->dev, "Regulator setup failed (%d)\n", ret);
>> +		goto clk_disable;
>> +	}
>> +
>> +	/* Reset the core and Enable SDHC mode */
>> +	core_memres = platform_get_resource_byname(pdev,
>> +						   IORESOURCE_MEM, "core_mem");
>> +	msm_host->core_mem = devm_ioremap(&pdev->dev, core_memres->start,
>> +					  resource_size(core_memres));
>> +
>> +	if (!msm_host->core_mem) {
>> +		dev_err(&pdev->dev, "Failed to remap registers\n");
>> +		ret = -ENOMEM;
>> +		goto vreg_deinit;
>> +	}
>> +
>> +	/* Set SW_RST bit in POWER register (Offset 0x0) */
>> +	writel_relaxed(CORE_SW_RST, msm_host->core_mem + CORE_POWER);
>> +	/* Set HC_MODE_EN bit in HC_MODE register */
>> +	writel_relaxed(HC_MODE_EN, (msm_host->core_mem + CORE_HC_MODE));
>> +
>> +	/*
>> +	 * Following are the deviations from SDHC spec v3.0 -
>> +	 * 1. Card detection is handled using separate GPIO.
>> +	 * 2. Bus power control is handled by interacting with PMIC.
>> +	 */
>> +	host->quirks |= SDHCI_QUIRK_BROKEN_CARD_DETECTION;
>> +
>> +	/* Setup PWRCTL irq */
>> +	msm_host->pwr_irq = platform_get_irq_byname(pdev, "pwr_irq");
>> +	if (msm_host->pwr_irq < 0) {
>> +		dev_err(&pdev->dev, "Failed to get pwr_irq by name (%d)\n",
>> +			msm_host->pwr_irq);
>> +		goto vreg_deinit;
>> +	}
>> +	ret = devm_request_threaded_irq(&pdev->dev, msm_host->pwr_irq, NULL,
>> +					sdhci_msm_pwr_irq, IRQF_ONESHOT,
>> +					dev_name(&pdev->dev), host);
>> +	if (ret) {
>> +		dev_err(&pdev->dev, "Request threaded irq(%d) failed (%d)\n",
>> +			msm_host->pwr_irq, ret);
>> +		goto vreg_deinit;
>> +	}
>> +
>> +	/* Enable pwr irq interrupts */
>> +	writel_relaxed(INT_MASK, (msm_host->core_mem + CORE_PWRCTL_MASK));
>> +
>> +	/* Set host capabilities */
>> +	msm_host->mmc->caps |= msm_host->pdata->caps;
>> +	msm_host->mmc->caps2 |= msm_host->pdata->caps2;
>> +
>> +	ret = sdhci_add_host(host);
>> +	if (ret) {
>> +		dev_err(&pdev->dev, "Add host failed (%d)\n", ret);
>> +		goto vreg_deinit;
>> +	}
>> +
>> +	/* Set core clk rate */
>> +	ret = clk_set_rate(msm_host->clk, host->max_clk);
>> +	if (ret) {
>> +		dev_err(&pdev->dev, "MClk rate set failed (%d)\n", ret);
>> +		goto remove_host;
>> +	}
>> +
>> +	host->mmc->max_current_180 = host->mmc->max_current_300 =
>> +	host->mmc->max_current_330 = sdhci_msm_get_vdd_max_current(msm_host);
>> +
>> +	/* Successful initialization */
>> +	goto out;
>> +
>> +remove_host:
>> +	dead = (readl_relaxed(host->ioaddr + SDHCI_INT_STATUS) == 0xffffffff);
>> +	sdhci_remove_host(host, dead);
>> +vreg_deinit:
>> +	sdhci_msm_vreg_init(&pdev->dev, msm_host->pdata, false);
>> +clk_disable:
>> +	if (!IS_ERR(msm_host->clk))
>> +		clk_disable_unprepare(msm_host->clk);
>> +pclk_disable:
>> +	if (!IS_ERR(msm_host->pclk))
>> +		clk_disable_unprepare(msm_host->pclk);
>> +bus_clk_disable:
>> +	if (!IS_ERR_OR_NULL(msm_host->bus_clk))
>> +		clk_disable_unprepare(msm_host->bus_clk);
>> +pltfm_free:
>> +	sdhci_pltfm_free(pdev);
>> +out:
>> +	return ret;
>> +}
>> +
>
> <snip>
>
>> +
>> +static struct platform_driver sdhci_msm_driver = {
>> +	.probe = sdhci_msm_probe,
>> +	.remove = sdhci_msm_remove,
>> +	.driver = {
>> +		   .name = "sdhci_msm",
>> +		   .owner = THIS_MODULE,
>> +		   .of_match_table = of_match_ptr(sdhci_msm_dt_match),
>
> of_match_ptr is not really required.
>

Thank you for the additional comments. I'll address all issues in the 
next version.

BR,
Georgi