diff --git a/atusb/fw/usb/usb.c b/atusb/fw/usb/usb.c
index f677d03..134ffc7 100644
--- a/atusb/fw/usb/usb.c
+++ b/atusb/fw/usb/usb.c
@@ -37,7 +37,7 @@ extern void panic(void);
 
 int (*user_setup)(const struct setup_request *setup);
 int (*user_get_descriptor)(uint8_t type, uint8_t index,
-    const uint8_t * const *reply, uint8_t *size);
+    const uint8_t **reply, uint8_t *size);
 void (*user_reset)(void);
 
 
diff --git a/atusb/fw/usb/usb.h b/atusb/fw/usb/usb.h
index 5e9a3dc..8868ffd 100644
--- a/atusb/fw/usb/usb.h
+++ b/atusb/fw/usb/usb.h
@@ -126,7 +126,7 @@ extern struct ep_descr eps[];
 
 extern int (*user_setup)(const struct setup_request *setup);
 extern int (*user_get_descriptor)(uint8_t type, uint8_t index,
-    const uint8_t * const *reply, uint8_t *size);
+    const uint8_t **reply, uint8_t *size);
 extern void (*user_reset)(void);