Merge #19459

19459: drivers/usbus_synopsys_dwc2: fix interrupt handling in DMA mode r=dylad a=gschorcht

### Contribution description

This PR fixes the interrupt handling for IN endpoints in DMA mode.

In DMA mode, both the `XFRC` (Transfer Complete) interrupt and the `TXFE` (TX FIFO Empty) interrupt for IN EP1 ... EPn were used to generate the `USBDEV_EVENT_TR_COMPLETE`. This led to problems with USBUS MSC. With this fix, the `TXFE` interrupt is used only in non-DMA mode or only for IN EP0 in DMA mode while the `XFRC` (Transfer Complete) is used only in DMA mode for IN EP1 ... EPn.

### Testing procedure

This PR should work together with PR #19458 for SD Card interface for a board with USB HS port, for example:
```
USEMODULE='sdcard_spi mtd_sdcard_default periph_usbdev_hs_ulpi' \
CFLAGS='-DSDCARD_SPI_PARAM_CLK=GPIO_PIN\(PORT_I,1\) -DSDCARD_SPI_PARAM_MISO=GPIO_PIN\(PORT_B,14\) -DSDCARD_SPI_PARAM_MOSI=GPIO_PIN\(PORT_B,15\) -DSDCARD_SPI_PARAM_CS=GPIO_PIN\(PORT_A,8\)' \
BOARD=stm32f746g-disco make -j8 -C tests/usbus_msc flash
```
It should still work for CDC ECM for such a board:
```
USEMODULE='periph_usbdev_hs_ulpi stdio_cdc_acm' BOARD=stm32f746g-disco make -j8 -C tests/usbus_cdc_ecm flash
```

### Issues/PRs references


Co-authored-by: Gunar Schorcht <gunar@schorcht.net>

drivers/usbdev_synopsys_dwc2/usbdev_synopsys_dwc2.c

@@ -1333,8 +1333,9 @@ static int _usbdev_ep_xmit(usbdev_ep_t *ep, uint8_t *buf, size_t len)
         _in_regs(conf, ep->num)->DIEPTSIZ = dieptsiz;
 
         /* Intentionally enabling this before the FIFO is filled, unmasking the
-        * interrupts after the FIFO is filled doesn't always trigger the ISR */
-        /* TX FIFO empty interrupt is only used in non-dma mode */
+         * interrupts after the FIFO is filled doesn't always trigger the ISR */
+        /* TX FIFO empty interrupt is used for EP0..EPn in non-DMA mode and
+         * for EP0 for DMA mode */
         _device_regs(conf)->DAINTMSK |= 1 << ep->num;
         _device_regs(conf)->DIEPEMPMSK |= 1 << ep->num;
 
@@ -1447,18 +1448,22 @@ static void _usbdev_ep_esr(usbdev_ep_t *ep)
     if (ep->dir == USB_EP_DIR_IN) {
         uint32_t status = _in_regs(conf, ep->num)->DIEPINT;
 
-        /* XFRC interrupt is used for all endpoints when DMA is enabled */
-        if (status & USB_OTG_DIEPINT_XFRC && _uses_dma(conf)) {
+        /* XFRC interrupt is used for EP1..EPn in DMA mode but
+         * cleared in any case */
+        if (status & USB_OTG_DIEPINT_XFRC) {
             _in_regs(conf, ep->num)->DIEPINT = USB_OTG_DIEPINT_XFRC;
-            if (ep->num != 0) {
+            if (_uses_dma(conf) && (ep->num != 0)) {
                 usbdev->usbdev.epcb(ep, USBDEV_EVENT_TR_COMPLETE);
             }
         }
         else
-        /* TXFE empty interrupt is only used with DMA disabled */
+        /* TXFE interrupt is used for all EPs in non-DMA mode but only for EP0
+         * in DMA mode. It is disabled in any case. */
         if (status & USB_OTG_DIEPINT_TXFE) {
             _device_regs(conf)->DIEPEMPMSK &= ~(1 << ep->num);
-            usbdev->usbdev.epcb(ep, USBDEV_EVENT_TR_COMPLETE);
+            if (!_uses_dma(conf) || (ep->num == 0)) {
+                usbdev->usbdev.epcb(ep, USBDEV_EVENT_TR_COMPLETE);
+            }
         }
     }
     else {