drivers: disk: add SDMMC zephyr disk driver

Add generic sdmmc zephyr disk driver, which uses the SDMMC subsystem

Signed-off-by: Daniel DeGrasse <daniel.degrasse@nxp.com>

drivers/disk/CMakeLists.txt

@@ -11,5 +11,6 @@ zephyr_library_sources_ifdef(CONFIG_DISK_DRIVER_RAM ramdisk.c)
 zephyr_library_sources_ifdef(CONFIG_SDMMC_OVER_SPI sdmmc_spi.c)
 zephyr_library_sources_ifdef(CONFIG_SDMMC_STM32 sdmmc_stm32.c)
 zephyr_library_sources_ifdef(CONFIG_SDMMC_USDHC usdhc.c)
+zephyr_library_sources_ifdef(CONFIG_SDMMC_SUBSYS sdmmc_subsys.c)
 
 endif()

drivers/disk/Kconfig.sdmmc

@@ -5,6 +5,7 @@
 DT_COMPAT_ZEPHYR_MMC_SPI_SLOT := zephyr,mmc-spi-slot
 DT_COMPAT_NXP_USDHC := nxp,imx-usdhc
 DT_COMPAT_ST_STM32_SDMMC := st,stm32-sdmmc
+DT_COMPAT_ZEPHYR_MMC := zephyr,sdmmc-disk
 
 config DISK_DRIVER_SDMMC
 	bool "SDMMC card driver"
@@ -33,6 +34,14 @@ config SDMMC_OVER_SPI
 	help
 	  File system on a SDHC card accessed over SPI.
 
+config SDMMC_SUBSYS
+	bool "SDMMC access via SD subsystem"
+	select SD_STACK
+	select SDHC
+	default $(dt_compat_enabled,$(DT_COMPAT_ZEPHYR_MMC))
+	help
+	  Enable SDMMC access via SD subsystem
+
 config SDMMC_USDHC
 	bool "NXP i.MXRT USDHC driver"
 	depends on (HAS_MCUX_USDHC1 || HAS_MCUX_USDHC2)

drivers/disk/sdmmc_subsys.c

@@ -0,0 +1,141 @@
+/*
+ * Copyright 2022 NXP
+ *
+ * SPDX-License-Identifier: Apache-2.0
+ */
+
+/*
+ * SDMMC disk driver using zephyr SD subsystem
+ */
+#define DT_DRV_COMPAT zephyr_sdmmc_disk
+
+#include <zephyr/sd/sdmmc.h>
+#include <zephyr/drivers/disk.h>
+
+
+enum sd_status {
+	SD_UNINIT,
+	SD_ERROR,
+	SD_OK,
+};
+
+struct sdmmc_config {
+	const struct device *host_controller;
+};
+
+struct sdmmc_data {
+	struct sd_card card;
+	enum sd_status status;
+	char *name;
+};
+
+
+static int disk_sdmmc_access_init(struct disk_info *disk)
+{
+	const struct device *dev = disk->dev;
+	const struct sdmmc_config *cfg = dev->config;
+	struct sdmmc_data *data = dev->data;
+	int ret;
+
+	if (data->status == SD_OK) {
+		/* Called twice, don't reinit */
+		return 0;
+	}
+
+	if (!sd_is_card_present(cfg->host_controller)) {
+		return DISK_STATUS_NOMEDIA;
+	}
+
+	ret = sd_init(cfg->host_controller, &data->card);
+	if (ret) {
+		data->status = SD_ERROR;
+		return ret;
+	}
+	data->status = SD_OK;
+	return 0;
+}
+
+static int disk_sdmmc_access_status(struct disk_info *disk)
+{
+	const struct device *dev = disk->dev;
+	const struct sdmmc_config *cfg = dev->config;
+	struct sdmmc_data *data = dev->data;
+
+	if (!sd_is_card_present(cfg->host_controller)) {
+		return DISK_STATUS_NOMEDIA;
+	}
+	if (data->status == SD_OK) {
+		return DISK_STATUS_OK;
+	} else {
+		return DISK_STATUS_UNINIT;
+	}
+}
+
+static int disk_sdmmc_access_read(struct disk_info *disk, uint8_t *buf,
+				 uint32_t sector, uint32_t count)
+{
+	const struct device *dev = disk->dev;
+	struct sdmmc_data *data = dev->data;
+
+	return sdmmc_read_blocks(&data->card, buf, sector, count);
+}
+
+static int disk_sdmmc_access_write(struct disk_info *disk, const uint8_t *buf,
+				 uint32_t sector, uint32_t count)
+{
+	const struct device *dev = disk->dev;
+	struct sdmmc_data *data = dev->data;
+
+	return sdmmc_write_blocks(&data->card, buf, sector, count);
+}
+
+static int disk_sdmmc_access_ioctl(struct disk_info *disk, uint8_t cmd, void *buf)
+{
+	const struct device *dev = disk->dev;
+	struct sdmmc_data *data = dev->data;
+
+	return sdmmc_ioctl(&data->card, cmd, buf);
+}
+
+static const struct disk_operations sdmmc_disk_ops = {
+	.init = disk_sdmmc_access_init,
+	.status = disk_sdmmc_access_status,
+	.read = disk_sdmmc_access_read,
+	.write = disk_sdmmc_access_write,
+	.ioctl = disk_sdmmc_access_ioctl,
+};
+
+static struct disk_info sdmmc_disk = {
+	.ops = &sdmmc_disk_ops,
+};
+
+static int disk_sdmmc_init(const struct device *dev)
+{
+	struct sdmmc_data *data = dev->data;
+
+	data->status = SD_UNINIT;
+	sdmmc_disk.dev = dev;
+	sdmmc_disk.name = data->name;
+
+	return disk_access_register(&sdmmc_disk);
+}
+
+#define DISK_ACCESS_SDMMC_INIT(n)						\
+	static const struct sdmmc_config sdmmc_config_##n = {			\
+		.host_controller = DEVICE_DT_GET(DT_INST_PARENT(n)),		\
+	};									\
+										\
+	static struct sdmmc_data sdmmc_data_##n = {				\
+		.name = CONFIG_SDMMC_VOLUME_NAME,				\
+	};									\
+										\
+	DEVICE_DT_INST_DEFINE(n,						\
+			&disk_sdmmc_init,					\
+			NULL,							\
+			&sdmmc_data_##n,					\
+			&sdmmc_config_##n,					\
+			POST_KERNEL,						\
+			CONFIG_SDMMC_INIT_PRIORITY,				\
+			NULL);
+
+DT_INST_FOREACH_STATUS_OKAY(DISK_ACCESS_SDMMC_INIT)