1 files changed, 2 insertions, 1 deletions
diff --git a/boot/usb.c b/boot/usb.c
index 1454750..7670491 100644
--- a/boot/usb.c
+++ b/boot/usb.c
@@ -51,6 +51,7 @@ static const char *usb_strings[] = {
   /* This string is used by ST Microelectronics' DfuSe utility. */
   "@Internal Flash   /0x08000000/04*016Kg,01*064Kg,07*128Kg",
 };
+#define N_USB_STRINGS  (sizeof(usb_strings)/sizeof(usb_strings[0]))
 
 void
 usb_set_config (usbd_device *usbd_dev, uint16_t wValue)
@@ -79,7 +80,7 @@ void usb (void)
   MAP_AF_100 (USB_DM, GPIO_AF10);
 
 
-  usbd_dev = usbd_init (&otgfs_usb_driver, &dev, &config, usb_strings, 4, usbd_control_buffer, sizeof (usbd_control_buffer));
+  usbd_dev = usbd_init (&otgfs_usb_driver, &dev, &config, usb_strings, N_USB_STRINGS, usbd_control_buffer, sizeof (usbd_control_buffer));
 
   OTG_FS_GCCFG |= OTG_GCCFG_NOVBUSSENS;
   OTG_FS_GCCFG &= ~OTG_GCCFG_VBUSASEN;