Re: [PATCH v1 2/2] mmc: sdhci-npcm: Add NPCM SDHCI driver

[Adrian Hunter]

On 30/11/22 17:08, Tomer Maimon wrote:
> Add Nuvoton NPCM BMC sdhci-pltfm controller driver.
> 
> Signed-off-by: Tomer Maimon <tmaimon77@xxxxxxxxx>
> ---
>  drivers/mmc/host/Kconfig      |  8 ++++
>  drivers/mmc/host/Makefile     |  1 +
>  drivers/mmc/host/sdhci-npcm.c | 81 +++++++++++++++++++++++++++++++++++
>  3 files changed, 90 insertions(+)
>  create mode 100644 drivers/mmc/host/sdhci-npcm.c
> 
> diff --git a/drivers/mmc/host/Kconfig b/drivers/mmc/host/Kconfig
> index fb1062a6394c..4b2d9ce4308c 100644
> --- a/drivers/mmc/host/Kconfig
> +++ b/drivers/mmc/host/Kconfig
> @@ -709,6 +709,14 @@ config MMC_TMIO
>  	  This provides support for the SD/MMC cell found in TC6393XB,
>  	  T7L66XB and also HTC ASIC3
>  
> +config MMC_SDHCI_NPCM
> +	tristate "Secure Digital Host Controller Interface support for NPCM"
> +	depends on ARCH_NPCM || COMPILE_TEST
> +	depends on MMC_SDHCI_PLTFM
> +	help
> +	  This provides support for the SD/eMMC controller found in
> +	  NPCM BMC family SoCs.
> +
>  config MMC_SDHI
>  	tristate "Renesas SDHI SD/SDIO controller support"
>  	depends on SUPERH || ARCH_RENESAS || COMPILE_TEST
> diff --git a/drivers/mmc/host/Makefile b/drivers/mmc/host/Makefile
> index 4e4ceb32c4b4..801086613d7f 100644
> --- a/drivers/mmc/host/Makefile
> +++ b/drivers/mmc/host/Makefile
> @@ -37,6 +37,7 @@ obj-$(CONFIG_MMC_SPI)		+= of_mmc_spi.o
>  obj-$(CONFIG_MMC_S3C)   	+= s3cmci.o
>  obj-$(CONFIG_MMC_SDRICOH_CS)	+= sdricoh_cs.o
>  obj-$(CONFIG_MMC_TMIO)		+= tmio_mmc.o
> +obj-$(CONFIG_MMC_SDHCI_NPCM)	+= sdhci-npcm.o
>  obj-$(CONFIG_MMC_TMIO_CORE)	+= tmio_mmc_core.o
>  obj-$(CONFIG_MMC_SDHI)		+= renesas_sdhi_core.o
>  obj-$(CONFIG_MMC_SDHI_SYS_DMAC)		+= renesas_sdhi_sys_dmac.o
> diff --git a/drivers/mmc/host/sdhci-npcm.c b/drivers/mmc/host/sdhci-npcm.c
> new file mode 100644
> index 000000000000..298c5f3e7c2b
> --- /dev/null
> +++ b/drivers/mmc/host/sdhci-npcm.c
> @@ -0,0 +1,81 @@
> +// SPDX-License-Identifier: GPL-2.0+
> +/*
> + * NPCM SDHC MMC host controller driver.
> + *
> + */
> +
> +#include <linux/clk.h>
> +#include <linux/err.h>
> +#include <linux/io.h>
> +#include <linux/mmc/host.h>
> +#include <linux/mmc/mmc.h>
> +#include <linux/module.h>
> +#include <linux/of.h>
> +
> +#include "sdhci-pltfm.h"
> +
> +static const struct sdhci_pltfm_data npcm_sdhci_pdata = {
> +	.quirks  = SDHCI_QUIRK_DELAY_AFTER_POWER,
> +	.quirks2 = SDHCI_QUIRK2_STOP_WITH_TC |
> +		   SDHCI_QUIRK2_NO_1_8_V,
> +};
> +
> +static int npcm_sdhci_probe(struct platform_device *pdev)
> +{
> +	struct sdhci_pltfm_host *pltfm_host;
> +	struct sdhci_host *host;
> +	u32 caps;
> +	int ret;
> +
> +	host = sdhci_pltfm_init(pdev, &npcm_sdhci_pdata, 0);
> +	if (IS_ERR(host))
> +		return PTR_ERR(host);
> +
> +	pltfm_host = sdhci_priv(host);
> +	pltfm_host->clk = devm_clk_get(&pdev->dev, NULL);

For an optional clock, something like:

	pltfm_host->clk = devm_clk_get_optional(&pdev->dev, NULL);
	if (IS_ERR(pltfm_host->clk))
		return PTR_ERR(pltfm_host->clk);

will handle -EPROBE_DEFER

> +
> +	if (!IS_ERR(pltfm_host->clk))
> +		clk_prepare_enable(pltfm_host->clk);
> +
> +	caps = sdhci_readl(host, SDHCI_CAPABILITIES);
> +	if (caps & SDHCI_CAN_DO_8BIT)
> +		host->mmc->caps |= MMC_CAP_8_BIT_DATA;
> +
> +	ret = mmc_of_parse(host->mmc);
> +	if (ret)
> +		goto err_sdhci_add;
> +
> +	ret = sdhci_add_host(host);
> +	if (ret)
> +		goto err_sdhci_add;
> +
> +	return 0;
> +
> +err_sdhci_add:
> +	clk_disable_unprepare(pltfm_host->clk);
> +	sdhci_pltfm_free(pdev);
> +	return ret;
> +}
> +
> +static const struct of_device_id npcm_sdhci_of_match[] = {
> +	{ .compatible = "nuvoton,npcm750-sdhci" },
> +	{ .compatible = "nuvoton,npcm845-sdhci" },
> +	{ }
> +};
> +MODULE_DEVICE_TABLE(of, npcm_sdhci_of_match);
> +
> +static struct platform_driver npcm_sdhci_driver = {
> +	.driver = {
> +		.name	= "npcm-sdhci",
> +		.of_match_table = npcm_sdhci_of_match,
> +		.pm	= &sdhci_pltfm_pmops,
> +	},
> +	.probe		= npcm_sdhci_probe,
> +	.remove		= sdhci_pltfm_unregister,
> +};
> +
> +module_platform_driver(npcm_sdhci_driver);
> +
> +MODULE_DESCRIPTION("NPCM Secure Digital Host Controller Interface driver");
> +MODULE_AUTHOR("Tomer Maimon <tomer.maimon@xxxxxxxxxxx>");
> +MODULE_LICENSE("GPL v2");

WARNING: Prefer "GPL" over "GPL v2" - see commit bf7fbeeae6db ("module: Cure the MODULE_LICENSE "GPL" vs. "GPL v2" bogosity")
#133: FILE: drivers/mmc/host/sdhci-npcm.c:81:
+MODULE_LICENSE("GPL v2");