diff --git a/ports/stm32/mpconfigboard_common.h b/ports/stm32/mpconfigboard_common.h
index 67a6ee990e..15513fba9c 100644
--- a/ports/stm32/mpconfigboard_common.h
+++ b/ports/stm32/mpconfigboard_common.h
@@ -548,11 +548,9 @@
 //  - MICROPY_HW_BDEV_SPIFLASH - pointer to a spi_bdev_t
 //  - MICROPY_HW_BDEV_SPIFLASH_CONFIG - pointer to an mp_spiflash_config_t
 //  - MICROPY_HW_BDEV_SPIFLASH_SIZE_BYTES - size in bytes of the SPI flash
-#define MICROPY_HW_BDEV_IOCTL(op, arg) ( \
-    (op) == BDEV_IOCTL_NUM_BLOCKS ? (MICROPY_HW_BDEV_SPIFLASH_SIZE_BYTES / FLASH_BLOCK_SIZE) : \
-    (op) == BDEV_IOCTL_INIT ? spi_bdev_ioctl(MICROPY_HW_BDEV_SPIFLASH, (op), (uint32_t)MICROPY_HW_BDEV_SPIFLASH_CONFIG) : \
-    spi_bdev_ioctl(MICROPY_HW_BDEV_SPIFLASH, (op), (arg)) \
-    )
+// The board can specify the SPI flash chip(s) being used as comma separated list in:
+//  - MICROPY_HW_SPIFLASH_DEVICES
+#define MICROPY_HW_BDEV_IOCTL(op, arg) (spi_bdev_ioctl(MICROPY_HW_BDEV_SPIFLASH, (op), (arg)))
 #define MICROPY_HW_BDEV_READBLOCKS(dest, bl, n) spi_bdev_readblocks(MICROPY_HW_BDEV_SPIFLASH, (dest), (bl), (n))
 #define MICROPY_HW_BDEV_WRITEBLOCKS(src, bl, n) spi_bdev_writeblocks(MICROPY_HW_BDEV_SPIFLASH, (src), (bl), (n))
 #endif
diff --git a/ports/stm32/spibdev.c b/ports/stm32/spibdev.c
index fecd4a9915..5366b41cb7 100644
--- a/ports/stm32/spibdev.c
+++ b/ports/stm32/spibdev.c
@@ -29,16 +29,33 @@
 #include "irq.h"
 #include "led.h"
 #include "storage.h"
+#include "drivers/memory/external_flash_device.h"
 
 #if MICROPY_HW_ENABLE_STORAGE
 
 int32_t spi_bdev_ioctl(spi_bdev_t *bdev, uint32_t op, uint32_t arg) {
     switch (op) {
         case BDEV_IOCTL_INIT:
+            #ifdef MICROPY_HW_BDEV_SPIFLASH_CONFIG
+            if (!arg) {
+                arg = (uint32_t)(MICROPY_HW_BDEV_SPIFLASH_CONFIG);
+            }
+            #endif
             bdev->spiflash.config = (const mp_spiflash_config_t *)arg;
-            mp_spiflash_init(&bdev->spiflash);
+            int ret = mp_spiflash_init(&bdev->spiflash);
             bdev->flash_tick_counter_last_write = 0;
-            return 0;
+            return ret;
+
+        case BDEV_IOCTL_NUM_BLOCKS:
+            #if MICROPY_HW_BDEV_SPIFLASH_SIZE_BYTES
+            return MICROPY_HW_BDEV_SPIFLASH_SIZE_BYTES / FLASH_BLOCK_SIZE;
+            #else
+            if (bdev->spiflash.device != NULL) {
+                external_flash_device *flash = (external_flash_device *)bdev->spiflash.device;
+                return flash->total_size / FLASH_BLOCK_SIZE;
+            }
+            return -1;
+            #endif
 
         case BDEV_IOCTL_IRQ_HANDLER: {
             int ret = 0;
diff --git a/ports/stm32/storage.c b/ports/stm32/storage.c
index 97286ba865..2e6d185b77 100644
--- a/ports/stm32/storage.c
+++ b/ports/stm32/storage.c
@@ -48,11 +48,11 @@ static void storage_systick_callback(uint32_t ticks_ms);
 
 void storage_init(void) {
     if (!storage_is_initialised) {
-        storage_is_initialised = true;
-
         systick_enable_dispatch(SYSTICK_DISPATCH_STORAGE, storage_systick_callback);
 
-        MICROPY_HW_BDEV_IOCTL(BDEV_IOCTL_INIT, 0);
+        if (MICROPY_HW_BDEV_IOCTL(BDEV_IOCTL_INIT, 0) == 0) {
+            storage_is_initialised = true;
+        }
 
         #if defined(MICROPY_HW_BDEV2_IOCTL)
         MICROPY_HW_BDEV2_IOCTL(BDEV_IOCTL_INIT, 0);