[nrf fromtree] drivers: udc_dwc2: Rearm isochronous OUT endpoints during incompisoout

Rearm isochronous endpoints when handling incomplete iso out interrupt
to make it possible to rearm the endpoint in time (before SOF),
especially when operating at High-Speed.

Signed-off-by: Tomasz Moń <[email protected]>
(cherry picked from commit 6eb2fa8)

Author: tmon-nordic

drivers/usb/udc/udc_dwc2.c

@@ -121,6 +121,7 @@ struct udc_dwc2_data {
 	/* Isochronous endpoint enabled (IN on bits 0-15, OUT on bits 16-31) */
 	uint32_t iso_enabled;
 	uint16_t iso_in_rearm;
+	uint16_t iso_out_rearm;
 	uint16_t ep_out_disable;
 	uint16_t ep_out_stall;
 	uint16_t txf_set;
@@ -2776,6 +2777,7 @@ static inline void dwc2_handle_oepint(const struct device *dev)
 	while (epint) {
 		uint8_t n = find_lsb_set(epint) - 1;
 		mem_addr_t doepint_reg = (mem_addr_t)&base->out_ep[n].doepint;
+		mem_addr_t doepctl_reg = (mem_addr_t)&base->out_ep[n].doepctl;
 		uint32_t doepint;
 		uint32_t status;
 
@@ -2828,7 +2830,20 @@ static inline void dwc2_handle_oepint(const struct device *dev)
 		}
 
 		if (status & USB_DWC2_DOEPINT_EPDISBLD) {
+			uint32_t doepctl = sys_read32(doepctl_reg);
+
 			k_event_post(&priv->ep_disabled, BIT(16 + n));
+
+			if ((usb_dwc2_get_depctl_eptype(doepctl) == USB_DWC2_DEPCTL_EPTYPE_ISO) &&
+			    (priv->iso_out_rearm & BIT(n))) {
+				struct udc_ep_config *cfg;
+
+				/* Try to queue next packet before SOF */
+				cfg = udc_get_ep_cfg(dev, n | USB_EP_DIR_OUT);
+				dwc2_handle_xfer_next(dev, cfg);
+
+				priv->iso_out_rearm &= ~BIT(n);
+			}
 		}
 
 		epint &= ~BIT(n);
@@ -2913,6 +2928,7 @@ static void dwc2_handle_incompisoout(const struct device *dev)
 		((priv->sof_num & 1) ? USB_DWC2_DEPCTL_DPID : 0) |
 		USB_DWC2_DEPCTL_USBACTEP;
 	uint32_t eps = (priv->iso_enabled & 0xFFFF0000UL) >> 16;
+	uint16_t rearm = 0;
 
 	while (eps) {
 		uint8_t i = find_lsb_set(eps) - 1;
@@ -2935,12 +2951,17 @@ static void dwc2_handle_incompisoout(const struct device *dev)
 			buf = udc_buf_get(cfg);
 			if (buf) {
 				udc_submit_ep_event(dev, buf, 0);
+
+				rearm |= BIT(i);
 			}
 		}
 
 		eps &= ~BIT(i);
 	}
 
+	/* Mark endpoints to re-arm in EPDISBLD handler */
+	priv->iso_out_rearm = rearm;
+
 	sys_write32(USB_DWC2_GINTSTS_INCOMPISOOUT, gintsts_reg);
 }