3 files changed, 62 insertions, 6 deletions

diff --git a/drivers/usb/core/config.c b/drivers/usb/core/config.c
index 42468bbeffd2..baf5bc844b6f 100644
--- a/drivers/usb/core/config.c
+++ b/drivers/usb/core/config.c
@@ -507,8 +507,8 @@ static int usb_parse_endpoint(struct device *ddev, int cfgno,
 	}
 
 	/* Parse a possible eUSB2 periodic endpoint companion descriptor */
-	if (bcdUSB == 0x0220 && d->wMaxPacketSize == 0 &&
-	    (usb_endpoint_xfer_isoc(d) || usb_endpoint_xfer_int(d)))
+	if (udev->speed == USB_SPEED_HIGH && bcdUSB == 0x0220 &&
+	    !le16_to_cpu(d->wMaxPacketSize) && usb_endpoint_is_isoc_in(d))
 		usb_parse_eusb2_isoc_endpoint_companion(ddev, cfgno, inum, asnum,
 							endpoint, buffer, size);
 
diff --git a/drivers/usb/core/urb.c b/drivers/usb/core/urb.c
index 7a76d5a62db1..ff8df16cca35 100644
--- a/drivers/usb/core/urb.c
+++ b/drivers/usb/core/urb.c
@@ -372,6 +372,7 @@ int usb_submit_urb(struct urb *urb, gfp_t mem_flags)
 	struct usb_host_endpoint	*ep;
 	int				is_out;
 	unsigned int			allowed;
+	bool				is_eusb2_isoch_double;
 
 	if (!urb || !urb->complete)
 		return -EINVAL;
@@ -434,7 +435,8 @@ int usb_submit_urb(struct urb *urb, gfp_t mem_flags)
 		return -ENODEV;
 
 	max = usb_endpoint_maxp(&ep->desc);
-	if (max <= 0) {
+	is_eusb2_isoch_double = usb_endpoint_is_hs_isoc_double(dev, ep);
+	if (!max && !is_eusb2_isoch_double) {
 		dev_dbg(&dev->dev,
 			"bogus endpoint ep%d%s in %s (bad maxpacket %d)\n",
 			usb_endpoint_num(&ep->desc), is_out ? "out" : "in",
@@ -467,9 +469,13 @@ int usb_submit_urb(struct urb *urb, gfp_t mem_flags)
 			max = le32_to_cpu(isoc_ep_comp->dwBytesPerInterval);
 		}
 
-		/* "high bandwidth" mode, 1-3 packets/uframe? */
-		if (dev->speed == USB_SPEED_HIGH)
-			max *= usb_endpoint_maxp_mult(&ep->desc);
+		/* High speed, 1-3 packets/uframe, max 6 for eUSB2 double bw */
+		if (dev->speed == USB_SPEED_HIGH) {
+			if (is_eusb2_isoch_double)
+				max = le32_to_cpu(ep->eusb2_isoc_ep_comp.dwBytesPerInterval);
+			else
+				max *= usb_endpoint_maxp_mult(&ep->desc);
+		}
 
 		if (urb->number_of_packets <= 0)
 			return -EINVAL;
diff --git a/drivers/usb/core/usb.c b/drivers/usb/core/usb.c
index fca7735fc660..b88b6271cb30 100644
--- a/drivers/usb/core/usb.c
+++ b/drivers/usb/core/usb.c
@@ -1110,6 +1110,56 @@ void usb_free_noncoherent(struct usb_device *dev, size_t size,
 }
 EXPORT_SYMBOL_GPL(usb_free_noncoherent);
 
+/**
+ * usb_endpoint_max_periodic_payload - Get maximum payload bytes per service
+ *				       interval
+ * @udev: The USB device
+ * @ep: The endpoint
+ *
+ * Returns: the maximum number of bytes isochronous or interrupt endpoint @ep
+ * can transfer during a service interval, or 0 for other endpoints.
+ */
+u32 usb_endpoint_max_periodic_payload(struct usb_device *udev,
+				      const struct usb_host_endpoint *ep)
+{
+	if (!usb_endpoint_xfer_isoc(&ep->desc) &&
+	    !usb_endpoint_xfer_int(&ep->desc))
+		return 0;
+
+	switch (udev->speed) {
+	case USB_SPEED_SUPER_PLUS:
+		if (USB_SS_SSP_ISOC_COMP(ep->ss_ep_comp.bmAttributes))
+			return le32_to_cpu(ep->ssp_isoc_ep_comp.dwBytesPerInterval);
+		fallthrough;
+	case USB_SPEED_SUPER:
+		return le16_to_cpu(ep->ss_ep_comp.wBytesPerInterval);
+	default:
+		if (usb_endpoint_is_hs_isoc_double(udev, ep))
+			return le32_to_cpu(ep->eusb2_isoc_ep_comp.dwBytesPerInterval);
+		return usb_endpoint_maxp(&ep->desc) * usb_endpoint_maxp_mult(&ep->desc);
+	}
+}
+EXPORT_SYMBOL_GPL(usb_endpoint_max_periodic_payload);
+
+/**
+ * usb_endpoint_is_hs_isoc_double - Tell whether an endpoint uses USB 2
+ *                                  Isochronous Double IN Bandwidth
+ * @udev: The USB device
+ * @ep: The endpoint
+ *
+ * Returns: true if an endpoint @ep conforms to USB 2 Isochronous Double IN
+ * Bandwidth ECN, false otherwise.
+ */
+bool usb_endpoint_is_hs_isoc_double(struct usb_device *udev,
+				    const struct usb_host_endpoint *ep)
+{
+	return ep->eusb2_isoc_ep_comp.bDescriptorType &&
+		le16_to_cpu(udev->descriptor.bcdUSB) == 0x220 &&
+		usb_endpoint_is_isoc_in(&ep->desc) &&
+		!le16_to_cpu(ep->desc.wMaxPacketSize);
+}
+EXPORT_SYMBOL_GPL(usb_endpoint_is_hs_isoc_double);
+
 /*
  * Notifications of device and interface registration
  */