diff --git a/payloads/libpayload/drivers/usb/ehci.c b/payloads/libpayload/drivers/usb/ehci.c
index 6e9f03aff0..35292e5706 100644
--- a/payloads/libpayload/drivers/usb/ehci.c
+++ b/payloads/libpayload/drivers/usb/ehci.c
@@ -270,6 +270,7 @@ static void free_qh_and_tds(ehci_qh_t *qh, qtd_t *cur)
 
 static int wait_for_tds(qtd_t *head)
 {
+	/* returns the amount of bytes *not* transmitted, or -1 for error */
 	int result = 0;
 	qtd_t *cur = head;
 	while (1) {
@@ -291,16 +292,18 @@ static int wait_for_tds(qtd_t *head)
 		if (timeout < 0) {
 			usb_debug("Error: ehci: queue transfer "
 				"processing timed out.\n");
-			return 1;
+			return -1;
 		}
 		if (cur->token & QTD_HALTED) {
 			usb_debug("ERROR with packet\n");
 			dump_td(virt_to_phys(cur));
 			usb_debug("-----------------\n");
-			return 1;
+			return -1;
 		}
+		result += (cur->token & QTD_TOTAL_LEN_MASK)
+				>> QTD_TOTAL_LEN_SHIFT;
 		if (cur->next_qtd & 1) {
-			return 0;
+			break;
 		}
 		if (0) dump_td(virt_to_phys(cur));
 		/* helps debugging the TD chain */
@@ -338,13 +341,13 @@ static int ehci_process_async_schedule(
 	int result;
 
 	/* make sure async schedule is disabled */
-	if (ehci_set_async_schedule(ehcic, 0)) return 1;
+	if (ehci_set_async_schedule(ehcic, 0)) return -1;
 
 	/* hook up QH */
 	ehcic->operation->asynclistaddr = virt_to_phys(qhead);
 
 	/* start async schedule */
-	if (ehci_set_async_schedule(ehcic, 1)) return 1;
+	if (ehci_set_async_schedule(ehcic, 1)) return -1;
 
 	/* wait for result */
 	result = wait_for_tds(head);
@@ -358,6 +361,7 @@ static int ehci_process_async_schedule(
 static int ehci_bulk (endpoint_t *ep, int size, u8 *data, int finalize)
 {
 	int result = 0;
+	int remaining = size;
 	int endp = ep->endpoint & 0xf;
 	int pid = (ep->direction==IN)?EHCI_IN:EHCI_OUT;
 
@@ -365,7 +369,7 @@ static int ehci_bulk (endpoint_t *ep, int size, u8 *data, int finalize)
 	if (ep->dev->speed < 2) {
 		/* we need a split transaction */
 		if (closest_usb2_hub(ep->dev, &hubaddr, &hubport))
-			return 1;
+			return -1;
 	}
 
 	qtd_t *head = memalign(64, sizeof(qtd_t));
@@ -375,12 +379,12 @@ static int ehci_bulk (endpoint_t *ep, int size, u8 *data, int finalize)
 		cur->token = QTD_ACTIVE |
 			(pid << QTD_PID_SHIFT) |
 			(0 << QTD_CERR_SHIFT);
-		u32 chunk = fill_td(cur, data, size);
-		size -= chunk;
+		u32 chunk = fill_td(cur, data, remaining);
+		remaining -= chunk;
 		data += chunk;
 
 		cur->alt_next_qtd = QTD_TERMINATE;
-		if (size == 0) {
+		if (remaining == 0) {
 			cur->next_qtd = virt_to_phys(0) | QTD_TERMINATE;
 			break;
 		} else {
@@ -411,10 +415,13 @@ static int ehci_bulk (endpoint_t *ep, int size, u8 *data, int finalize)
 
 	result = ehci_process_async_schedule(
 			EHCI_INST(ep->dev->controller), qh, head);
+	if (result >= 0)
+		result = size - result;
 
 	ep->toggle = (cur->token & QTD_TOGGLE_MASK) >> QTD_TOGGLE_SHIFT;
 
 	free_qh_and_tds(qh, head);
+
 	return result;
 }
 
@@ -432,7 +439,7 @@ static int ehci_control (usbdev_t *dev, direction_t dir, int drlen, void *devreq
 	if (dev->speed < 2) {
 		/* we need a split transaction */
 		if (closest_usb2_hub(dev, &hubaddr, &hubport))
-			return 1;
+			return -1;
 		non_hs_ctrl_ep = 1;
 	}
 
@@ -499,6 +506,8 @@ static int ehci_control (usbdev_t *dev, direction_t dir, int drlen, void *devreq
 
 	result = ehci_process_async_schedule(
 			EHCI_INST(dev->controller), qh, head);
+	if (result >= 0)
+		result = dalen - result;
 
 	free_qh_and_tds(qh, head);
 	return result;
diff --git a/payloads/libpayload/drivers/usb/ohci.c b/payloads/libpayload/drivers/usb/ohci.c
index 51ea8fb433..8a09a953f4 100644
--- a/payloads/libpayload/drivers/usb/ohci.c
+++ b/payloads/libpayload/drivers/usb/ohci.c
@@ -44,7 +44,7 @@ static int ohci_control (usbdev_t *dev, direction_t dir, int drlen, void *devreq
 static void* ohci_create_intr_queue (endpoint_t *ep, int reqsize, int reqcount, int reqtiming);
 static void ohci_destroy_intr_queue (endpoint_t *ep, void *queue);
 static u8* ohci_poll_intr_queue (void *queue);
-static void ohci_process_done_queue(ohci_t *ohci, int spew_debug);
+static int ohci_process_done_queue(ohci_t *ohci, int spew_debug);
 
 #ifdef USB_DEBUG
 static void
@@ -319,13 +319,13 @@ wait_for_ed(usbdev_t *dev, ed_t *head, int pages)
 		usb_debug("Error: ohci: endpoint "
 			"descriptor processing timed out.\n");
 	/* Clear the done queue. */
-	ohci_process_done_queue(OHCI_INST(dev->controller), 1);
+	int result = ohci_process_done_queue(OHCI_INST(dev->controller), 1);
 
 	if (head->head_pointer & 1) {
 		usb_debug("HALTED!\n");
-		return 1;
+		return -1;
 	}
-	return 0;
+	return result;
 }
 
 static void
@@ -353,6 +353,7 @@ static int
 ohci_control (usbdev_t *dev, direction_t dir, int drlen, void *devreq, int dalen,
 	      unsigned char *data)
 {
+	int remaining = dalen;
 	td_t *cur;
 
 	// pages are specified as 4K in OHCI, so don't use getpagesize()
@@ -390,21 +391,21 @@ ohci_control (usbdev_t *dev, direction_t dir, int drlen, void *devreq, int dalen
 		cur->current_buffer_pointer = virt_to_phys(data);
 		pages--;
 		int consumed = (4096 - ((unsigned long)data % 4096));
-		if (consumed >= dalen) {
+		if (consumed >= remaining) {
 			// end of data is within same page
-			cur->buffer_end = virt_to_phys(data + dalen - 1);
-			dalen = 0;
+			cur->buffer_end = virt_to_phys(data + remaining - 1);
+			remaining = 0;
 			/* assert(pages == 0); */
 		} else {
-			dalen -= consumed;
+			remaining -= consumed;
 			data += consumed;
 			pages--;
-			int second_page_size = dalen;
-			if (dalen > 4096) {
+			int second_page_size = remaining;
+			if (remaining > 4096) {
 				second_page_size = 4096;
 			}
 			cur->buffer_end = virt_to_phys(data + second_page_size - 1);
-			dalen -= second_page_size;
+			remaining -= second_page_size;
 			data += second_page_size;
 		}
 	}
@@ -452,7 +453,7 @@ ohci_control (usbdev_t *dev, direction_t dir, int drlen, void *devreq, int dalen
 	OHCI_INST(dev->controller)->opreg->HcControl |= ControlListEnable;
 	OHCI_INST(dev->controller)->opreg->HcCommandStatus = ControlListFilled;
 
-	int failure = wait_for_ed(dev, head,
+	int result = wait_for_ed(dev, head,
 			(dalen==0)?0:(last_page - first_page + 1));
 	/* Wait some frames before and one after disabling list access. */
 	mdelay(4);
@@ -462,7 +463,10 @@ ohci_control (usbdev_t *dev, direction_t dir, int drlen, void *devreq, int dalen
 	/* free memory */
 	ohci_free_ed(head);
 
-	return failure;
+	if (result >= 0)
+		result = dalen - result;
+
+	return result;
 }
 
 /* finalize == 1: if data is of packet aligned size, add a zero length packet */
@@ -470,6 +474,7 @@ static int
 ohci_bulk (endpoint_t *ep, int dalen, u8 *data, int finalize)
 {
 	int i;
+	int remaining = dalen;
 	usb_debug("bulk: %x bytes from %x, finalize: %x, maxpacketsize: %x\n", dalen, data, finalize, ep->maxpacketsize);
 
 	td_t *cur, *next;
@@ -499,28 +504,28 @@ ohci_bulk (endpoint_t *ep, int dalen, u8 *data, int finalize)
                         TD_CC_NOACCESS;
 		cur->current_buffer_pointer = virt_to_phys(data);
 		pages--;
-		if (dalen == 0) {
+		if (remaining == 0) {
 			/* magic TD for empty packet transfer */
 			cur->current_buffer_pointer = 0;
 			cur->buffer_end = 0;
 			/* assert((pages == 0) && finalize); */
 		}
 		int consumed = (4096 - ((unsigned long)data % 4096));
-		if (consumed >= dalen) {
+		if (consumed >= remaining) {
 			// end of data is within same page
-			cur->buffer_end = virt_to_phys(data + dalen - 1);
-			dalen = 0;
+			cur->buffer_end = virt_to_phys(data + remaining - 1);
+			remaining = 0;
 			/* assert(pages == finalize); */
 		} else {
-			dalen -= consumed;
+			remaining -= consumed;
 			data += consumed;
 			pages--;
-			int second_page_size = dalen;
-			if (dalen > 4096) {
+			int second_page_size = remaining;
+			if (remaining > 4096) {
 				second_page_size = 4096;
 			}
 			cur->buffer_end = virt_to_phys(data + second_page_size - 1);
-			dalen -= second_page_size;
+			remaining -= second_page_size;
 			data += second_page_size;
 		}
 		/* One more TD. */
@@ -556,7 +561,7 @@ ohci_bulk (endpoint_t *ep, int dalen, u8 *data, int finalize)
 	OHCI_INST(ep->dev->controller)->opreg->HcControl |= BulkListEnable;
 	OHCI_INST(ep->dev->controller)->opreg->HcCommandStatus = BulkListFilled;
 
-	int failure = wait_for_ed(ep->dev, head,
+	int result = wait_for_ed(ep->dev, head,
 			(dalen==0)?0:(last_page - first_page + 1));
 	/* Wait some frames before and one after disabling list access. */
 	mdelay(4);
@@ -568,12 +573,12 @@ ohci_bulk (endpoint_t *ep, int dalen, u8 *data, int finalize)
 	/* free memory */
 	ohci_free_ed(head);
 
-	if (failure) {
-		/* try cleanup */
+	if (result >= 0)
+		result = dalen - result;
+	else
 		clear_stall(ep);
-	}
 
-	return failure;
+	return result;
 }
 
 
@@ -778,9 +783,11 @@ ohci_poll_intr_queue(void *const q_)
 	return data;
 }
 
-static void
+static int
 ohci_process_done_queue(ohci_t *const ohci, const int spew_debug)
 {
+	/* returns the amount of bytes *not* transmitted for short packets */
+	int result = 0;
 	int i, j;
 
 	/* Temporary queue of interrupt queue TDs (to reverse order). */
@@ -788,7 +795,7 @@ ohci_process_done_queue(ohci_t *const ohci, const int spew_debug)
 
 	/* Check if done head has been written. */
 	if (!(ohci->opreg->HcInterruptStatus & WritebackDoneHead))
-		return;
+		return 0;
 	/* Fetch current done head.
 	   Lsb is only interesting for hw interrupts. */
 	u32 phys_done_queue = ohci->hcca->HccaDoneHead & ~1;
@@ -805,7 +812,11 @@ ohci_process_done_queue(ohci_t *const ohci, const int spew_debug)
 
 		switch (done_td->config & TD_QUEUETYPE_MASK) {
 		case TD_QUEUETYPE_ASYNC:
-			/* Free processed async TDs. */
+			/* Free processed async TDs and count short transfer. */
+			if (done_td->current_buffer_pointer)
+				result += (done_td->buffer_end & 0xfff) -
+						(done_td->current_buffer_pointer
+						& 0xfff) + 1;
 			free((void *)done_td);
 			break;
 		case TD_QUEUETYPE_INTR: {
@@ -862,5 +873,7 @@ ohci_process_done_queue(ohci_t *const ohci, const int spew_debug)
 	}
 	if (spew_debug)
 		usb_debug("processed %d done tds, %d intr tds thereof.\n", i, j);
+
+	return result;
 }
 
diff --git a/payloads/libpayload/drivers/usb/uhci.c b/payloads/libpayload/drivers/usb/uhci.c
index df9bdca03c..94d855205b 100644
--- a/payloads/libpayload/drivers/usb/uhci.c
+++ b/payloads/libpayload/drivers/usb/uhci.c
@@ -383,7 +383,7 @@ uhci_control (usbdev_t *dev, direction_t dir, int drlen, void *devreq, int dalen
 	} else {
 		usb_debug ("control packet, req %x\n", req);
 		td_dump (td);
-		result = 1;
+		result = -1;
 	}
 	free (tds);
 	return result;
@@ -465,7 +465,7 @@ uhci_bulk (endpoint_t *ep, int size, u8 *data, int finalize)
 		usb_debug("Stalled. Trying to clean up.\n");
 		clear_stall (ep);
 		free (tds);
-		return 1;
+		return -1;
 	}
 	ep->toggle = toggle;
 	free (tds);
diff --git a/payloads/libpayload/drivers/usb/usb.c b/payloads/libpayload/drivers/usb/usb.c
index 23561c40aa..83d03735a8 100644
--- a/payloads/libpayload/drivers/usb/usb.c
+++ b/payloads/libpayload/drivers/usb/usb.c
@@ -157,7 +157,7 @@ get_descriptor (usbdev_t *dev, unsigned char bmRequestType, int descType,
 	dr.wValue = (descType << 8) | descIdx;
 	dr.wIndex = langID;
 	dr.wLength = 8;
-	if (dev->controller->control (dev, IN, sizeof (dr), &dr, 8, buf)) {
+	if (dev->controller->control (dev, IN, sizeof (dr), &dr, 8, buf) < 0) {
 		usb_debug ("getting descriptor size (type %x) failed\n",
 			descType);
 	}
@@ -181,7 +181,7 @@ get_descriptor (usbdev_t *dev, unsigned char bmRequestType, int descType,
 	memset (result, 0, size);
 	dr.wLength = size;
 	if (dev->controller->
-	    control (dev, IN, sizeof (dr), &dr, size, result)) {
+	    control (dev, IN, sizeof (dr), &dr, size, result) < 0) {
 		usb_debug ("getting descriptor (type %x, size %x) failed\n",
 			descType, size);
 	}
@@ -213,7 +213,7 @@ clear_feature (usbdev_t *dev, int endp, int feature, int rtype)
 	dr.wValue = feature;
 	dr.wIndex = endp;
 	dr.wLength = 0;
-	return dev->controller->control (dev, OUT, sizeof (dr), &dr, 0, 0);
+	return dev->controller->control (dev, OUT, sizeof (dr), &dr, 0, 0) < 0;
 }
 
 int
@@ -272,7 +272,7 @@ set_address (hci_t *controller, int speed, int hubport, int hubaddr)
 	dev->endpoints[0].toggle = 0;
 	dev->endpoints[0].direction = SETUP;
 	mdelay (50);
-	if (dev->controller->control (dev, OUT, sizeof (dr), &dr, 0, 0)) {
+	if (dev->controller->control (dev, OUT, sizeof (dr), &dr, 0, 0) < 0) {
 		usb_debug ("set_address failed\n");
 		return -1;
 	}
diff --git a/payloads/libpayload/drivers/usb/usbmsc.c b/payloads/libpayload/drivers/usb/usbmsc.c
index f1de483170..2d28fbd12f 100644
--- a/payloads/libpayload/drivers/usb/usbmsc.c
+++ b/payloads/libpayload/drivers/usb/usbmsc.c
@@ -184,7 +184,7 @@ reset_transport (usbdev_t *dev)
 	dr.wLength = 0;
 
 	/* if any of these fails, detach device, as we are lost */
-	if (dev->controller->control (dev, OUT, sizeof (dr), &dr, 0, 0) ||
+	if (dev->controller->control (dev, OUT, sizeof (dr), &dr, 0, 0) < 0 ||
 			clear_stall (MSC_INST (dev)->bulk_in) ||
 			clear_stall (MSC_INST (dev)->bulk_out)) {
 		usb_debug ("Detaching unresponsive device.\n");
@@ -211,9 +211,8 @@ get_max_luns (usbdev_t *dev)
 	dr.wValue = 0;
 	dr.wIndex = 0;
 	dr.wLength = 1;
-	if (dev->controller->control (dev, IN, sizeof (dr), &dr, 1, &luns)) {
+	if (dev->controller->control (dev, IN, sizeof (dr), &dr, 1, &luns) < 0)
 		luns = 0;	// assume only 1 lun if req fails
-	}
 	return luns;
 }
 
@@ -239,10 +238,10 @@ wrap_cbw (cbw_t *cbw, int datalen, cbw_direction dir, const u8 *cmd,
 static int
 get_csw (endpoint_t *ep, csw_t *csw)
 {
-	if (ep->dev->controller->bulk (ep, sizeof (csw_t), (u8 *) csw, 1)) {
+	if (ep->dev->controller->bulk (ep, sizeof (csw_t), (u8 *) csw, 1) < 0) {
 		clear_stall (ep);
 		if (ep->dev->controller->bulk
-				(ep, sizeof (csw_t), (u8 *) csw, 1)) {
+				(ep, sizeof (csw_t), (u8 *) csw, 1) < 0) {
 			return reset_transport (ep->dev);
 		}
 	}
@@ -265,17 +264,17 @@ execute_command (usbdev_t *dev, cbw_direction dir, const u8 *cb, int cblen,
 	}
 	wrap_cbw (&cbw, buflen, dir, cb, cblen);
 	if (dev->controller->
-	    bulk (MSC_INST (dev)->bulk_out, sizeof (cbw), (u8 *) &cbw, 0)) {
+	    bulk (MSC_INST (dev)->bulk_out, sizeof (cbw), (u8 *) &cbw, 0) < 0) {
 		return reset_transport (dev);
 	}
 	if (buflen > 0) {
 		if (dir == cbw_direction_data_in) {
 			if (dev->controller->
-			    bulk (MSC_INST (dev)->bulk_in, buflen, buf, 0))
+			    bulk (MSC_INST (dev)->bulk_in, buflen, buf, 0) < 0)
 				clear_stall (MSC_INST (dev)->bulk_in);
 		} else {
 			if (dev->controller->
-			    bulk (MSC_INST (dev)->bulk_out, buflen, buf, 0))
+			    bulk (MSC_INST (dev)->bulk_out, buflen, buf, 0) < 0)
 				clear_stall (MSC_INST (dev)->bulk_out);
 		}
 	}
diff --git a/payloads/libpayload/drivers/usb/xhci.c b/payloads/libpayload/drivers/usb/xhci.c
index 341b5969c2..512cf5d106 100644
--- a/payloads/libpayload/drivers/usb/xhci.c
+++ b/payloads/libpayload/drivers/usb/xhci.c
@@ -242,7 +242,7 @@ static int
 xhci_control (usbdev_t *dev, direction_t dir, int drlen, void *devreq, int dalen,
 	      unsigned char *data)
 {
-	return 1;
+	return -1;
 }
 
 /* finalize == 1: if data is of packet aligned size, add a zero length packet */
@@ -252,7 +252,7 @@ xhci_bulk (endpoint_t *ep, int size, u8 *data, int finalize)
 	int maxpsize = ep->maxpacketsize;
 	if (maxpsize == 0)
 		fatal("MaxPacketSize == 0!!!");
-	return 1;
+	return -1;
 }
 
 /* create and hook-up an intr queue into device schedule */