fs: fat_fs: make IOCTL call to de-initialize disk in fatfs_unmount()

Make call to de-initialize disk in fatfs_unmount(). This will permit the
disk to be reinitialized when it is mounted with fatfs_mount().

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

modules/fatfs/zfs_diskio.c

@@ -1,6 +1,7 @@
 /*
  * Copyright (c) 2018-2021 Zephyr contributors
  * Copyright (c) 2022 Nordic Semiconductor ASA
+ * Copyright 2024 NXP
  *
  * SPDX-License-Identifier: Apache-2.0
  */
@@ -12,6 +13,7 @@
  */
 #include <ff.h>
 #include <diskio.h>	/* FatFs lower layer API */
+#include <zfs_diskio.h> /* Zephyr specific FatFS API */
 #include <zephyr/storage/disk_access.h>
 
 static const char * const pdrv_str[] = {FF_VOLUME_STRS};
@@ -31,13 +33,9 @@ DSTATUS disk_status(BYTE pdrv)
 /* Initialize a Drive */
 DSTATUS disk_initialize(BYTE pdrv)
 {
-	__ASSERT(pdrv < ARRAY_SIZE(pdrv_str), "pdrv out-of-range\n");
+	uint8_t param = DISK_IOCTL_POWER_ON;
 
-	if (disk_access_init(pdrv_str[pdrv]) != 0) {
-		return STA_NOINIT;
-	} else {
-		return RES_OK;
-	}
+	return disk_ioctl(pdrv, CTRL_POWER, &param);
 }
 
 /* Read Sector(s) */
@@ -109,6 +107,27 @@ DRESULT disk_ioctl(BYTE pdrv, BYTE cmd, void *buff)
 		}
 		break;
 
+	/* Optional IOCTL command used by Zephyr fs_unmount implementation,
+	 * not called by FATFS
+	 */
+	case CTRL_POWER:
+		if (((*(uint8_t *)buff)) == DISK_IOCTL_POWER_OFF) {
+			/* Power disk off */
+			if (disk_access_ioctl(pdrv_str[pdrv],
+					      DISK_IOCTL_CTRL_DEINIT,
+					      NULL) != 0) {
+				ret = RES_ERROR;
+			}
+		} else {
+			/* Power disk on */
+			if (disk_access_ioctl(pdrv_str[pdrv],
+					      DISK_IOCTL_CTRL_INIT,
+					      NULL) != 0) {
+				ret = STA_NOINIT;
+			}
+		}
+		break;
+
 	default:
 		ret = RES_PARERR;
 		break;

modules/fatfs/zfs_diskio.h

@@ -0,0 +1,22 @@
+/*
+ * Copyright 2024 NXP
+ *
+ * SPDX-License-Identifier: Apache-2.0
+ */
+
+#ifndef ZEPHYR_MODULES_FATFS_ZFS_DISKIO_H_
+#define ZEPHYR_MODULES_FATFS_ZFS_DISKIO_H_
+/*
+ * Header file for Zephyr specific portions of the FatFS disk interface.
+ * These APIs are internal to Zephyr's FatFS VFS implementation
+ */
+
+/*
+ * Values that can be passed to buffer pointer used by disk_ioctl() when
+ * sending CTRL_POWER IOCTL
+ */
+#define DISK_IOCTL_POWER_OFF 0x0
+#define DISK_IOCTL_POWER_ON 0x1
+
+
+#endif /* ZEPHYR_MODULES_FATFS_ZFS_DISKIO_H_ */

subsys/fs/fat_fs.c

@@ -1,5 +1,6 @@
 /*
  * Copyright (c) 2016 Intel Corporation.
+ * Copyright 2024 NXP
  *
  * SPDX-License-Identifier: Apache-2.0
  */
@@ -14,6 +15,10 @@
 #include <zephyr/fs/fs_sys.h>
 #include <zephyr/sys/__assert.h>
 #include <ff.h>
+#include <diskio.h>
+#include <zfs_diskio.h> /* Zephyr specific FatFS API */
+#include <zephyr/logging/log.h>
+LOG_MODULE_DECLARE(fs, CONFIG_FS_LOG_LEVEL);
 
 #define FATFS_MAX_FILE_NAME 12 /* Uses 8.3 SFN */
 
@@ -64,6 +69,23 @@ static int translate_error(int error)
 	return -EIO;
 }
 
+static int translate_disk_error(int error)
+{
+	switch (error) {
+	case RES_OK:
+		return 0;
+	case RES_WRPRT:
+		return -EPERM;
+	case RES_PARERR:
+		return -EINVAL;
+	case RES_NOTRDY:
+	case RES_ERROR:
+		return -EIO;
+	}
+
+	return -EIO;
+}
+
 /* Converts a zephyr path like /SD:/foo into a path digestible by FATFS by stripping the
  * leading slash, i.e. SD:/foo.
  */
@@ -463,10 +485,23 @@ static int fatfs_mount(struct fs_mount_t *mountp)
 static int fatfs_unmount(struct fs_mount_t *mountp)
 {
 	FRESULT res;
+	DRESULT disk_res;
+	uint8_t param = DISK_IOCTL_POWER_OFF;
 
 	res = f_mount(NULL, translate_path(mountp->mnt_point), 0);
+	if (res != FR_OK) {
+		LOG_ERR("Unmount failed (%d)", res);
+		return translate_error(res);
+	}
 
-	return translate_error(res);
+	/* Make direct disk IOCTL call to deinit disk */
+	disk_res = disk_ioctl(((FATFS *)mountp->fs_data)->pdrv, CTRL_POWER, &param);
+	if (disk_res != RES_OK) {
+		LOG_ERR("Could not power off disk (%d)", disk_res);
+		return translate_disk_error(disk_res);
+	}
+
+	return 0;
 }
 
 #if defined(CONFIG_FILE_SYSTEM_MKFS) && defined(CONFIG_FS_FATFS_MKFS)