Re: sending bulk request over interrupt endpoint

On Wed, 21 Feb 2007, Max Asbock wrote:

> I am looking at a UHCI usb device which has endpoints of type interrupt.
> A userspace daemon attempts to submit an urb of type bulk to the device.
> This fails and -EINVAl is returned.
> Is it legal to send a bulk request to an interrupt endpoint?
> proc_do_submiturb doesn't complain about this case.

You have found a bug in proc_do_submiturb().  It should indeed be legal to
submit a bulk request to an interrupt endpoint.

> The EINVAL comes from uhci_submit_interrupt because urb->interval is not
> initialized for a bulk request on an interrupt endpoint. 
> 
> I don't really know anything about USB, so I hope this makes some sense.
> The device and userspace daemon worked with earlier kernels. Maybe just
> by accident? 

It used to be that uhci-hcd did not check for illegal intervals in 
interrupt URBs.  Now it does; that's why the behavior has changed.

I believe the patch below will fix your problem.  Please let us know if it 
works.

Alan Stern



Index: usb-2.6/drivers/usb/core/devio.c
===================================================================
--- usb-2.6.orig/drivers/usb/core/devio.c
+++ usb-2.6/drivers/usb/core/devio.c
@@ -912,7 +912,7 @@ static int proc_do_submiturb(struct dev_
 	struct async *as;
 	struct usb_ctrlrequest *dr = NULL;
 	unsigned int u, totlen, isofrmlen;
-	int ret, interval = 0, ifnum = -1;
+	int ret, ifnum = -1;
 
 	if (uurb->flags & ~(USBDEVFS_URB_ISO_ASAP|USBDEVFS_URB_SHORT_NOT_OK|
 			   URB_NO_FSBR|URB_ZERO_PACKET))
@@ -992,7 +992,6 @@ static int proc_do_submiturb(struct dev_
 		if ((ep->desc.bmAttributes & USB_ENDPOINT_XFERTYPE_MASK)
 				!= USB_ENDPOINT_XFER_ISOC)
 			return -EINVAL;
-		interval = 1 << min (15, ep->desc.bInterval - 1);
 		isofrmlen = sizeof(struct usbdevfs_iso_packet_desc) * uurb->number_of_packets;
 		if (!(isopkt = kmalloc(isofrmlen, GFP_KERNEL)))
 			return -ENOMEM;
@@ -1021,10 +1020,6 @@ static int proc_do_submiturb(struct dev_
 		if ((ep->desc.bmAttributes & USB_ENDPOINT_XFERTYPE_MASK)
 				!= USB_ENDPOINT_XFER_INT)
 			return -EINVAL;
-		if (ps->dev->speed == USB_SPEED_HIGH)
-			interval = 1 << min (15, ep->desc.bInterval - 1);
-		else
-			interval = ep->desc.bInterval;
 		if (uurb->buffer_length > MAX_USBFS_BUFFER_SIZE)
 			return -EINVAL;
 		if (!access_ok((uurb->endpoint & USB_DIR_IN) ? VERIFY_WRITE : VERIFY_READ, uurb->buffer, uurb->buffer_length))
@@ -1053,7 +1048,11 @@ static int proc_do_submiturb(struct dev_
 	as->urb->setup_packet = (unsigned char*)dr;
 	as->urb->start_frame = uurb->start_frame;
 	as->urb->number_of_packets = uurb->number_of_packets;
-	as->urb->interval = interval;
+	if (uurb->type == USBDEVFS_URB_TYPE_ISO ||
+			ps->dev->speed == USB_SPEED_HIGH)
+		as->urb->interval = 1 << min(15, ep->desc.bInterval - 1);
+	else
+		as->urb->interval = ep->desc.bInterval;
         as->urb->context = as;
         as->urb->complete = async_completed;
 	for (totlen = u = 0; u < uurb->number_of_packets; u++) {
Index: usb-2.6/drivers/usb/core/message.c
===================================================================
--- usb-2.6.orig/drivers/usb/core/message.c
+++ usb-2.6/drivers/usb/core/message.c
@@ -221,10 +221,15 @@ int usb_bulk_msg(struct usb_device *usb_
 
 	if ((ep->desc.bmAttributes & USB_ENDPOINT_XFERTYPE_MASK) ==
 			USB_ENDPOINT_XFER_INT) {
+		int interval;
+
+		if (usb_dev->speed == USB_SPEED_HIGH)
+			interval = 1 << min(15, ep->desc.bInterval - 1);
+		else
+			interval = ep->desc.bInterval;
 		pipe = (pipe & ~(3 << 30)) | (PIPE_INTERRUPT << 30);
 		usb_fill_int_urb(urb, usb_dev, pipe, data, len,
-				usb_api_blocking_completion, NULL,
-				ep->desc.bInterval);
+				usb_api_blocking_completion, NULL, interval);
 	} else
 		usb_fill_bulk_urb(urb, usb_dev, pipe, data, len,
 				usb_api_blocking_completion, NULL);


-------------------------------------------------------------------------
Take Surveys. Earn Cash. Influence the Future of IT
Join SourceForge.net's Techsay panel and you'll get the chance to share your
opinions on IT & business topics through brief surveys-and earn cash
http://www.techsay.com/default.php?page=join.php&p=sourceforge&CID=DEVDEV
_______________________________________________
[email protected]
To unsubscribe, use the last form field at:
https://lists.sourceforge.net/lists/listinfo/linux-usb-devel