Merge pull request #15475 from OpenNuvoton/nvt_usbd_zlp

Nuvoton: Bug fix of Nuvoton HUSBD driver's endpoint write

Author: 0xc0170

targets/TARGET_NUVOTON/USBEndpoints_Nuvoton.cpp

@@ -915,11 +915,13 @@ static volatile int epComplete = 0;
 #define HSUSBD_GET_EP_MAX_PAYLOAD(ep)     HSUSBD->EP[ep].EPMPS
 #define HSUSBD_GET_EP_DATA_COUNT(ep)      (HSUSBD->EP[ep].EPDATCNT & 0xFFFFF)
 #define HSUSBD_SET_EP_SHORT_PACKET(ep)    HSUSBD->EP[ep].EPRSPCTL = ((HSUSBD->EP[ep].EPRSPCTL & 0x10) | 0x40)
+#define HSUSBD_SET_EP_ZERO_PACKET(ep)     HSUSBD->EP[ep].EPRSPCTL = ((HSUSBD->EP[ep].EPRSPCTL & 0x10) | 0x20)
 #define HSUSBD_GET_EP_INT_EN(ep)          HSUSBD->EP[ep].EPINTEN
 #elif defined (TARGET_NUC472)
 #define USBD_GET_EP_MAX_PAYLOAD(ep)       *((__IO uint32_t *) ((uint32_t)&USBD->EPAMPS + (uint32_t)(ep*0x28)))
 #define USBD_GET_EP_DATA_COUNT(ep)        *((__IO uint32_t *) ((uint32_t)&USBD->EPADATCNT + (uint32_t)(ep*0x28)))
 #define USBD_SET_EP_SHORT_PACKET(ep)      *((__IO uint32_t *) ((uint32_t)&USBD->EPARSPCTL + (uint32_t)(ep*0x28))) = ((*((__IO uint32_t *)((uint32_t)&USBD->EPARSPCTL+(uint32_t)(ep*0x28))) & 0x10) | 0x40)
+#define USBD_SET_EP_ZERO_PACKET(ep)       *((__IO uint32_t *) ((uint32_t)&USBD->EPARSPCTL + (uint32_t)(ep*0x28))) = (*((__IO uint32_t *)((uint32_t)&USBD->EPARSPCTL+(uint32_t)(ep*0x28))) & 0x10)
 #define USBD_SET_EP_BUF_FLUSH(ep)         *((__IO uint32_t *) ((uint32_t)&USBD->EPARSPCTL + (uint32_t)(ep*0x28))) = USBD_EPRSPCTL_FLUSH_Msk
 #define USBD_GET_EP_INT_EN(ep)            *((__IO uint32_t *) ((uint32_t)&USBD->EPAINTEN  + (uint32_t)(ep*0x28)))
 #define USBD_GET_EP_INT(ep)               *((__IO uint32_t *) ((uint32_t)&USBD->EPAINTSTS + (uint32_t)(ep*0x28)))
@@ -1699,6 +1701,18 @@ bool USBPhyHw::endpoint_write(usb_ep_t endpoint, uint8_t *data, uint32_t size)
         if (size > mps)
             return false;
 
+        /* Send Zero packet */
+        if (size == 0) {
+#if defined (TARGET_NUC472)
+            USBD_SET_EP_ZERO_PACKET(ep_hw_index);
+            USBD_ENABLE_EP_INT(ep_hw_index, USBD_GET_EP_INT_EN(ep_hw_index) | USBD_EPINTEN_TXPKIEN_Msk);
+#elif defined (TARGET_M480) || defined (TARGET_M460)
+            HSUSBD_SET_EP_ZERO_PACKET(ep_hw_index);
+            HSUSBD->EP[ep_hw_index].EPINTEN |= HSUSBD_EPINTEN_TXPKIEN_Msk;
+#endif
+            return true;
+        }
+
 #if defined (TARGET_NUC472)
         if(USBD_GET_EP_DATA_COUNT(ep_hw_index) & 0xFFFF)
         {