drivers: disk: add DISK_IOCTL_CTRL_DEINIT command to supported IOCTLs

Add DISK_IOCTL_CTRL_DEINIT ioctl command to disk subsystem. When
disk_access_ioctl() is called with this command, the disk will be
de-initialized. After this IOCTL completes, the disk can safely be
reinitialized.

Fixes #60628

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

drivers/disk/flashdisk.c

@@ -435,6 +435,7 @@ static int disk_flash_access_ioctl(struct disk_info *disk, uint8_t cmd, void *bu
 	ctx = CONTAINER_OF(disk, struct flashdisk_data, info);
 
 	switch (cmd) {
+	case DISK_IOCTL_CTRL_DEINIT:
 	case DISK_IOCTL_CTRL_SYNC:
 		k_mutex_lock(&ctx->lock, K_FOREVER);
 		rc = flashdisk_cache_commit(ctx);

drivers/disk/loopback_disk.c

@@ -107,6 +107,7 @@ static int loopback_disk_access_ioctl(struct disk_info *disk, uint8_t cmd, void
 		*(uint32_t *)buff = LOOPBACK_SECTOR_SIZE;
 		return 0;
 	}
+	case DISK_IOCTL_CTRL_DEINIT:
 	case DISK_IOCTL_CTRL_SYNC:
 		return fs_sync(&ctx->file);
 	case DISK_IOCTL_CTRL_INIT:

drivers/disk/mmc_subsys.c

@@ -85,6 +85,13 @@ static int disk_mmc_access_ioctl(struct disk_info *disk, uint8_t cmd, void *buf)
 	switch (cmd) {
 	case DISK_IOCTL_CTRL_INIT:
 		return disk_mmc_access_init(disk);
+	case DISK_IOCTL_CTRL_DEINIT:
+		mmc_ioctl(&data->card, DISK_IOCTL_CTRL_SYNC, NULL);
+		/* sd_init() will toggle power to MMC, so we can just mark
+		 * disk as uninitialized
+		 */
+		data->status = SD_UNINIT;
+		return 0;
 	default:
 		return mmc_ioctl(&data->card, cmd, buf);
 	}

drivers/disk/nvme/nvme_disk.c

@@ -178,6 +178,7 @@ static int nvme_disk_ioctl(struct disk_info *disk, uint8_t cmd, void *buff)
 		*(uint32_t *)buff = nvme_namespace_get_sector_size(ns);
 
 		break;
+	case DISK_IOCTL_CTRL_DEINIT:
 	case DISK_IOCTL_CTRL_SYNC:
 		ret = nvme_disk_flush(ns);
 		break;

drivers/disk/ramdisk.c

@@ -94,6 +94,7 @@ static int disk_ram_access_ioctl(struct disk_info *disk, uint8_t cmd, void *buff
 		*(uint32_t *)buff  = 1U;
 		break;
 	case DISK_IOCTL_CTRL_INIT:
+	case DISK_IOCTL_CTRL_DEINIT:
 		break;
 	default:
 		return -EINVAL;

drivers/disk/sdmmc_stm32.c

@@ -307,14 +307,18 @@ static int stm32_sdmmc_access_init(struct disk_info *disk)
 	return 0;
 }
 
-#if !defined(CONFIG_SDMMC_STM32_EMMC)
-static void stm32_sdmmc_access_deinit(struct stm32_sdmmc_priv *priv)
+static int stm32_sdmmc_access_deinit(struct stm32_sdmmc_priv *priv)
 {
+#if defined(CONFIG_SDMMC_STM32_EMMC)
+	HAL_MMC_DeInit(&priv->hsd);
+#else
 	HAL_SD_DeInit(&priv->hsd);
 
 	stm32_sdmmc_clock_disable(priv);
-}
 #endif
+	priv->status = DISK_STATUS_UNINIT;
+	return 0;
+}
 
 static int stm32_sdmmc_access_status(struct disk_info *disk)
 {
@@ -483,6 +487,8 @@ static int stm32_sdmmc_access_ioctl(struct disk_info *disk, uint8_t cmd,
 		break;
 	case DISK_IOCTL_CTRL_INIT:
 		return stm32_sdmmc_access_init(disk);
+	case DISK_IOCTL_CTRL_DEINIT:
+		return stm32_sdmmc_access_deinit(priv);
 	default:
 		return -EINVAL;
 	}

drivers/disk/sdmmc_subsys.c

@@ -89,8 +89,16 @@ static int disk_sdmmc_access_ioctl(struct disk_info *disk, uint8_t cmd, void *bu
 	const struct device *dev = disk->dev;
 	struct sdmmc_data *data = dev->data;
 
+	switch (cmd) {
 	case DISK_IOCTL_CTRL_INIT:
 		return disk_sdmmc_access_init(disk);
+	case DISK_IOCTL_CTRL_DEINIT:
+		sdmmc_ioctl(&data->card, DISK_IOCTL_CTRL_SYNC, NULL);
+		/* sd_init() will toggle power to SDMMC, so we can just mark
+		 * disk as uninitialized
+		 */
+		data->status = SD_UNINIT;
+		return 0;
 	default:
 		return sdmmc_ioctl(&data->card, cmd, buf);
 	}

include/zephyr/drivers/disk.h

@@ -55,6 +55,18 @@ extern "C" {
  * device
  */
 #define DISK_IOCTL_CTRL_INIT			6
+/** Deinitialize the disk. This IOCTL can be used to de-initialize the disk,
+ * enabling it to be removed from the system if the disk is hot-pluggable.
+ * Disk usage is reference counted, so for a given disk the
+ * `DISK_IOCTL_CTRL_DEINIT` IOCTL must be issued as many times as the
+ * `DISK_IOCTL_CTRL_INIT` IOCTL was issued in order to de-initialize it.
+ *
+ * This macro optionally accepts a pointer to a boolean as the `buf` parameter,
+ * which if true indicates the disk should be forcibly stopped, ignoring all
+ * reference counts. The disk driver must report success if a forced stop is
+ * requested, but this operation is inherently unsafe.
+ */
+#define DISK_IOCTL_CTRL_DEINIT			7
 
 /**
  * @brief Possible return bitmasks for disk_status()

include/zephyr/storage/disk_access.h

@@ -44,7 +44,8 @@ extern "C" {
  * @ref disk_access_ioctl with the IOCTL @ref DISK_IOCTL_CTRL_INIT.
  *
  * Disk initialization is reference counted, so only the first successful call
- * to initialize a uninitialized disk will actually initialize the disk
+ * to initialize a uninitialized (or previously de-initialized) disk will
+ * actually initialize the disk
  *
  * @param[in] pdrv          Disk name
  *

subsys/disk/disk_access.c

@@ -139,6 +139,24 @@ int disk_access_ioctl(const char *pdrv, uint8_t cmd, void *buf)
 				LOG_ERR("Disk reference count at max value");
 			}
 			break;
+		case DISK_IOCTL_CTRL_DEINIT:
+			if ((buf != NULL) && (*((bool *)buf))) {
+				/* Force deinit disk */
+				disk->refcnt = 0U;
+				disk->ops->ioctl(disk, cmd, buf);
+				rc = 0;
+			} else if (disk->refcnt == 1U) {
+				rc = disk->ops->ioctl(disk, cmd, buf);
+				if (rc == 0) {
+					disk->refcnt--;
+				}
+			} else if (disk->refcnt > 0) {
+				disk->refcnt--;
+				rc = 0;
+			} else {
+				LOG_WRN("Disk is already deinitialized");
+			}
+			break;
 		default:
 			rc = disk->ops->ioctl(disk, cmd, buf);
 		}