diff --git a/ports/stm32/usbd_cdc_interface.c b/ports/stm32/usbd_cdc_interface.c
index f6590ade52..3ab6157c46 100644
--- a/ports/stm32/usbd_cdc_interface.c
+++ b/ports/stm32/usbd_cdc_interface.c
@@ -186,7 +186,7 @@ void HAL_PCD_SOFCallback(PCD_HandleTypeDef *hpcd) {
 
         buffptr = cdc->tx_buf_ptr_out_shadow;
 
-        if (USBD_CDC_TransmitPacket(cdc->base.usbd, buffsize, &cdc->tx_buf[buffptr]) == USBD_OK) {
+        if (USBD_CDC_TransmitPacket(&cdc->base, buffsize, &cdc->tx_buf[buffptr]) == USBD_OK) {
             cdc->tx_buf_ptr_out_shadow += buffsize;
             if (cdc->tx_buf_ptr_out_shadow == USBD_CDC_TX_DATA_SIZE) {
                 cdc->tx_buf_ptr_out_shadow = 0;
@@ -226,7 +226,7 @@ int8_t usbd_cdc_receive(usbd_cdc_state_t *cdc_in, size_t len) {
     }
 
     // initiate next USB packet transfer
-    USBD_CDC_ReceivePacket(cdc->base.usbd, cdc->rx_packet_buf);
+    USBD_CDC_ReceivePacket(&cdc->base, cdc->rx_packet_buf);
 
     return USBD_OK;
 }
diff --git a/ports/stm32/usbdev/class/inc/usbd_cdc_msc_hid.h b/ports/stm32/usbdev/class/inc/usbd_cdc_msc_hid.h
index b9671ef3a6..d56bdf6b2c 100644
--- a/ports/stm32/usbdev/class/inc/usbd_cdc_msc_hid.h
+++ b/ports/stm32/usbdev/class/inc/usbd_cdc_msc_hid.h
@@ -162,8 +162,8 @@ int USBD_SelectMode(usbd_cdc_msc_hid_state_t *usbd, uint32_t mode, USBD_HID_Mode
 // returns the current usb mode
 uint8_t USBD_GetMode(usbd_cdc_msc_hid_state_t *usbd);
 
-uint8_t USBD_CDC_ReceivePacket(usbd_cdc_msc_hid_state_t *usbd, uint8_t *buf);
-uint8_t USBD_CDC_TransmitPacket(usbd_cdc_msc_hid_state_t *usbd, size_t len, const uint8_t *buf);
+uint8_t USBD_CDC_ReceivePacket(usbd_cdc_state_t *cdc, uint8_t *buf);
+uint8_t USBD_CDC_TransmitPacket(usbd_cdc_state_t *cdc, size_t len, const uint8_t *buf);
 
 static inline void USBD_MSC_RegisterStorage(usbd_cdc_msc_hid_state_t *usbd, USBD_StorageTypeDef *fops) {
     usbd->MSC_BOT_ClassData.bdev_ops = fops;
diff --git a/ports/stm32/usbdev/class/src/usbd_cdc_msc_hid.c b/ports/stm32/usbdev/class/src/usbd_cdc_msc_hid.c
index c2030043fb..3e27d1c6c5 100644
--- a/ports/stm32/usbdev/class/src/usbd_cdc_msc_hid.c
+++ b/ports/stm32/usbdev/class/src/usbd_cdc_msc_hid.c
@@ -1111,13 +1111,13 @@ uint8_t *USBD_CDC_MSC_HID_GetDeviceQualifierDescriptor(USBD_HandleTypeDef *pdev,
 }
 
 // data received on non-control OUT endpoint
-uint8_t USBD_CDC_TransmitPacket(usbd_cdc_msc_hid_state_t *usbd, size_t len, const uint8_t *buf) {
-    if (usbd->cdc->tx_in_progress == 0) {
+uint8_t USBD_CDC_TransmitPacket(usbd_cdc_state_t *cdc, size_t len, const uint8_t *buf) {
+    if (cdc->tx_in_progress == 0) {
         // transmit next packet
-        USBD_LL_Transmit(usbd->pdev, CDC_IN_EP, (uint8_t*)buf, len);
+        USBD_LL_Transmit(cdc->usbd->pdev, cdc->in_ep, (uint8_t*)buf, len);
 
         // Tx transfer in progress
-        usbd->cdc->tx_in_progress = 1;
+        cdc->tx_in_progress = 1;
         return USBD_OK;
     } else {
         return USBD_BUSY;
@@ -1125,17 +1125,17 @@ uint8_t USBD_CDC_TransmitPacket(usbd_cdc_msc_hid_state_t *usbd, size_t len, cons
 }
 
 // prepare OUT endpoint for reception
-uint8_t USBD_CDC_ReceivePacket(usbd_cdc_msc_hid_state_t *usbd, uint8_t *buf) {
+uint8_t USBD_CDC_ReceivePacket(usbd_cdc_state_t *cdc, uint8_t *buf) {
     // Suspend or Resume USB Out process
 
     #if !USBD_SUPPORT_HS_MODE
-    if (usbd->pdev->dev_speed == USBD_SPEED_HIGH) {
+    if (cdc->usbd->pdev->dev_speed == USBD_SPEED_HIGH) {
         return USBD_FAIL;
     }
     #endif
 
     // Prepare Out endpoint to receive next packet
-    USBD_LL_PrepareReceive(usbd->pdev, CDC_OUT_EP, buf, usbd_cdc_max_packet(usbd->pdev));
+    USBD_LL_PrepareReceive(cdc->usbd->pdev, CDC_OUT_EP, buf, usbd_cdc_max_packet(cdc->usbd->pdev));
 
     return USBD_OK;
 }