mmc: sdhci-npcm: Add NPCM SDHCI driver

Add Nuvoton NPCM BMC sdhci-pltfm controller driver.

Signed-off-by: Tomer Maimon <tmaimon77@gmail.com>
Acked-by: Adrian Hunter <adrian.hunter@intel.com>
Reviewed-by: Andy Shevchenko <andy.shevchenko@gmail.com>
Link: https://lore.kernel.org/r/20231002200610.129799-3-tmaimon77@gmail.com
Signed-off-by: Ulf Hansson <ulf.hansson@linaro.org>

Author: tmaimon

drivers/mmc/host/Kconfig

@@ -429,6 +429,14 @@ config MMC_SDHCI_IPROC
 
 	  If unsure, say N.
 
+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_MESON_GX
 	tristate "Amlogic S905/GX*/AXG SD/MMC Host Controller support"
 	depends on ARCH_MESON|| COMPILE_TEST

drivers/mmc/host/Makefile

@@ -89,6 +89,7 @@ obj-$(CONFIG_MMC_SDHCI_OF_DWCMSHC)	+= sdhci-of-dwcmshc.o
 obj-$(CONFIG_MMC_SDHCI_OF_SPARX5)	+= sdhci-of-sparx5.o
 obj-$(CONFIG_MMC_SDHCI_BCM_KONA)	+= sdhci-bcm-kona.o
 obj-$(CONFIG_MMC_SDHCI_IPROC)		+= sdhci-iproc.o
+obj-$(CONFIG_MMC_SDHCI_NPCM)		+= sdhci-npcm.o
 obj-$(CONFIG_MMC_SDHCI_MSM)		+= sdhci-msm.o
 obj-$(CONFIG_MMC_SDHCI_ST)		+= sdhci-st.o
 obj-$(CONFIG_MMC_SDHCI_MICROCHIP_PIC32)	+= sdhci-pic32.o

drivers/mmc/host/sdhci-npcm.c

@@ -0,0 +1,94 @@
+// SPDX-License-Identifier: GPL-2.0+
+/*
+ * NPCM SDHC MMC host controller driver.
+ *
+ * Copyright (c) 2023 Nuvoton Technology corporation.
+ */
+
+#include <linux/clk.h>
+#include <linux/err.h>
+#include <linux/io.h>
+#include <linux/mmc/host.h>
+#include <linux/mmc/mmc.h>
+#include <linux/mod_devicetable.h>
+#include <linux/module.h>
+#include <linux/of.h>
+
+#include "sdhci-pltfm.h"
+
+static const struct sdhci_pltfm_data npcm7xx_sdhci_pdata = {
+	.quirks  = SDHCI_QUIRK_DELAY_AFTER_POWER,
+	.quirks2 = SDHCI_QUIRK2_STOP_WITH_TC |
+		   SDHCI_QUIRK2_NO_1_8_V,
+};
+
+static const struct sdhci_pltfm_data npcm8xx_sdhci_pdata = {
+	.quirks  = SDHCI_QUIRK_DELAY_AFTER_POWER,
+	.quirks2 = SDHCI_QUIRK2_STOP_WITH_TC,
+};
+
+static int npcm_sdhci_probe(struct platform_device *pdev)
+{
+	const struct sdhci_pltfm_data *data;
+	struct sdhci_pltfm_host *pltfm_host;
+	struct device *dev = &pdev->dev;
+	struct sdhci_host *host;
+	u32 caps;
+	int ret;
+
+	data = of_device_get_match_data(dev);
+	if (!data)
+		return -EINVAL;
+
+	host = sdhci_pltfm_init(pdev, data, 0);
+	if (IS_ERR(host))
+		return PTR_ERR(host);
+
+	pltfm_host = sdhci_priv(host);
+
+	pltfm_host->clk = devm_clk_get_optional_enabled(dev, NULL);
+	if (IS_ERR(pltfm_host->clk)) {
+		ret = PTR_ERR(pltfm_host->clk);
+		goto err_sdhci;
+	}
+
+	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;
+
+	ret = sdhci_add_host(host);
+	if (ret)
+		goto err_sdhci;
+
+	return 0;
+
+err_sdhci:
+	sdhci_pltfm_free(pdev);
+	return ret;
+}
+
+static const struct of_device_id npcm_sdhci_of_match[] = {
+	{ .compatible = "nuvoton,npcm750-sdhci", .data = &npcm7xx_sdhci_pdata },
+	{ .compatible = "nuvoton,npcm845-sdhci", .data = &npcm8xx_sdhci_pdata },
+	{ }
+};
+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_new	= sdhci_pltfm_remove,
+};
+module_platform_driver(npcm_sdhci_driver);
+
+MODULE_DESCRIPTION("NPCM Secure Digital Host Controller Interface driver");
+MODULE_AUTHOR("Tomer Maimon <tomer.maimon@nuvoton.com>");
+MODULE_LICENSE("GPL");