diff --git a/src/portable/st/stm32_fsdev/dcd_stm32_fsdev.c b/src/portable/st/stm32_fsdev/dcd_stm32_fsdev.c
index 702b32f9c..648e8f8d0 100644
--- a/src/portable/st/stm32_fsdev/dcd_stm32_fsdev.c
+++ b/src/portable/st/stm32_fsdev/dcd_stm32_fsdev.c
@@ -649,7 +649,6 @@ void dcd_int_handler(uint8_t rhport) {
   /* Put SOF flag at the beginning of ISR in case to get least amount of jitter if it is used for timing purposes */
   if(int_status & USB_ISTR_SOF) {
     clear_istr_bits(USB_ISTR_SOF);
-    if (tu_stm32_sof_cb) tu_stm32_sof_cb();
     dcd_event_sof(0, USB->FNR & USB_FNR_FN, true);
   }
 
diff --git a/src/portable/st/stm32_fsdev/dcd_stm32_fsdev_pvt_st.h b/src/portable/st/stm32_fsdev/dcd_stm32_fsdev_pvt_st.h
index ded13ae14..98cf008d4 100644
--- a/src/portable/st/stm32_fsdev/dcd_stm32_fsdev_pvt_st.h
+++ b/src/portable/st/stm32_fsdev/dcd_stm32_fsdev_pvt_st.h
@@ -119,9 +119,6 @@
 // Volatile is also needed to prevent the optimizer from changing access to 32-bit (as 32-bit access is forbidden)
 static __IO uint16_t * const pma = (__IO uint16_t*)USB_PMAADDR;
 
-// This callback is called on SOF and can be used to e.g. capture a timer value for timing purposes
-TU_ATTR_WEAK void tu_stm32_sof_cb(void);
-
 // prototypes
 TU_ATTR_ALWAYS_INLINE static inline __IO uint16_t* pcd_ep_rx_cnt_ptr(USB_TypeDef * USBx, uint32_t bEpNum);
 TU_ATTR_ALWAYS_INLINE static inline __IO uint16_t* pcd_ep_tx_cnt_ptr(USB_TypeDef * USBx, uint32_t bEpNum);