Commit 774921a2 authored by David Brownell's avatar David Brownell Committed by Greg Kroah-Hartman

[PATCH] urb->transfer_flags updates

This patch fixes two problems that have already been discussed
on this list:

- USB_QUEUE_BULK is rather pointless (and UHCI-specific).
   If drivers really want only one bulk urb queued at a time,
   they just shouldn't issue such urbs till others complete.

     FIX:  remove it entirely.

- USB_DISABLE_SPD is horribly named (based on a UHCI flag).
   What it really does is turn non-ISO short reads into errors.

     FIX:  rename it.  Now it's URB_SHORT_NOT_OK.

I changed all the drivers using these two flags, including
corresponding changes in the "usbfs" API.

Most of the patch by volume is doc updates:

- Documentation/usb/URB.txt hadn't been updated in two years (!)
   and was pretty out of date.  It also had many details that were
   inappropriately specific to usb-uhci.
- Most of the URB flags weren't even commented as to intent.
- DISABLE_SPD was often documented as if it were SHORT_IS_OK.
- There was still some doc saying how iso should use urb->next.

There are also some related updates:

- Some of the submit sanity checks for transfer flags were
   overly broad ... SHORT_NOT_OK is only for reads, NO_FSBR
   is for non-periodic requests, ZERO_PACKET only for writes.
- The ohci-hcd code thought SHORT_NOT_OK worked for ISO.
- The uhci-hcd code thought QUEUE_BULK applied to non-bulk

Note that this patch doesn't update any of the "old" HCDs,
including usb-ohci-hcd.

In the case of usb-uhci{,-hcd} it'd have been painful to fix
the QUEUE_BULK logic.  That logic was, I think, the original
reason to have that flag!  So I count switching to "uhci-hcd"
as a win already ... :)
parent 9ad568e6
This diff is collapsed.
......@@ -22,9 +22,8 @@ USB-specific:
-ENODEV specified USB-device or bus doesn't exist
-ENXIO a control or interrupt URB is already queued to this endpoint;
or (UHCI only) a bulk URB is already queued to this endpoint
and USB_QUEUE_BULK wasn't used
-ENXIO host controller driver does not support queuing of this type
of urb. (treat as a host controller bug.)
-EINVAL a) Invalid transfer type specified (or not supported)
b) Invalid interrupt interval (0<=n<256)
......@@ -90,9 +89,9 @@ one or more packets could finish before an error stops further endpoint I/O.
greater than either the max packet size of the
endpoint or the remaining buffer size. "Babble".
-EREMOTEIO The endpoint returned less than max packet size
and that amount did not fill the specified buffer
(and USB_DISBLE_SPD was not set in transfer_flags)
-EREMOTEIO The data read from the endpoint did not fill the
specified buffer, and URB_SHORT_NOT_OK was set in
urb->transfer_flags.
-ETIMEDOUT transfer timed out, NAK
......
......@@ -176,7 +176,6 @@ static int hci_usb_rx_submit(struct hci_usb *husb, struct urb *urb)
pipe = usb_rcvbulkpipe(husb->udev, husb->bulk_in_ep);
FILL_BULK_URB(urb, husb->udev, pipe, skb->data, size, hci_usb_rx_complete, skb);
urb->transfer_flags = USB_QUEUE_BULK;
skb_queue_tail(&husb->pending_q, skb);
err = usb_submit_urb(urb, GFP_ATOMIC);
......@@ -318,7 +317,7 @@ static inline int hci_usb_send_bulk(struct hci_usb *husb, struct sk_buff *skb)
FILL_BULK_URB(urb, husb->udev, pipe, skb->data, skb->len,
hci_usb_tx_complete, skb);
urb->transfer_flags = USB_QUEUE_BULK | USB_ZERO_PACKET;
urb->transfer_flags = USB_ZERO_PACKET;
BT_DBG("%s urb %p len %d", husb->hdev.name, urb, skb->len);
......
......@@ -273,7 +273,7 @@ static void irda_usb_change_speed_xbofs(struct irda_usb_cb *self)
frame, IRDA_USB_SPEED_MTU,
speed_bulk_callback, self);
urb->transfer_buffer_length = USB_IRDA_HEADER;
urb->transfer_flags = USB_QUEUE_BULK | USB_ASYNC_UNLINK;
urb->transfer_flags = USB_ASYNC_UNLINK;
urb->timeout = MSECS_TO_JIFFIES(100);
/* Irq disabled -> GFP_ATOMIC */
......@@ -410,7 +410,7 @@ static int irda_usb_hard_xmit(struct sk_buff *skb, struct net_device *netdev)
urb->transfer_buffer_length = skb->len;
/* Note : unlink *must* be Asynchronous because of the code in
* irda_usb_net_timeout() -> call in irq - Jean II */
urb->transfer_flags = USB_QUEUE_BULK | USB_ASYNC_UNLINK;
urb->transfer_flags = USB_ASYNC_UNLINK;
/* This flag (USB_ZERO_PACKET) indicates that what we send is not
* a continuous stream of data but separate packets.
* In this case, the USB layer will insert an empty USB frame (TD)
......@@ -736,7 +736,6 @@ static void irda_usb_submit(struct irda_usb_cb *self, struct sk_buff *skb, struc
usb_rcvbulkpipe(self->usbdev, self->bulk_in_ep),
skb->data, skb->truesize,
irda_usb_receive, skb);
urb->transfer_flags = USB_QUEUE_BULK;
/* Note : unlink *must* be synchronous because of the code in
* irda_usb_net_close() -> free the skb - Jean II */
urb->status = 0;
......
......@@ -537,7 +537,6 @@ static int bluetooth_write (struct tty_struct * tty, int from_user, const unsign
/* build up our urb */
FILL_BULK_URB (urb, bluetooth->dev, usb_sndbulkpipe(bluetooth->dev, bluetooth->bulk_out_endpointAddress),
urb->transfer_buffer, buffer_size, bluetooth_write_bulk_callback, bluetooth);
urb->transfer_flags |= USB_QUEUE_BULK;
/* send it down the pipe */
retval = usb_submit_urb(urb, GFP_KERNEL);
......
......@@ -780,7 +780,7 @@ static int proc_submiturb(struct dev_state *ps, void *arg)
if (copy_from_user(&uurb, arg, sizeof(uurb)))
return -EFAULT;
if (uurb.flags & ~(USBDEVFS_URB_ISO_ASAP|USBDEVFS_URB_DISABLE_SPD|USBDEVFS_URB_QUEUE_BULK|
if (uurb.flags & ~(USBDEVFS_URB_ISO_ASAP|USBDEVFS_URB_SHORT_NOT_OK|
USB_NO_FSBR|USB_ZERO_PACKET))
return -EINVAL;
if (!uurb.buffer)
......
......@@ -105,7 +105,7 @@ struct urb * usb_get_urb(struct urb *urb)
* any transfer flags.
*
* Successful submissions return 0; otherwise this routine returns a
* negative error number. If the submission is successful, the complete
* negative error number. If the submission is successful, the complete()
* fuction of the urb will be called when the USB host driver is
* finished with the urb (either a successful transmission, or some
* error case.)
......@@ -117,8 +117,8 @@ struct urb * usb_get_urb(struct urb *urb)
* driver which issued the request. The completion handler may then
* immediately free or reuse that URB.
*
* Bulk URBs will be queued if the USB_QUEUE_BULK transfer flag is set
* in the URB. This can be used to maximize bandwidth utilization by
* Bulk URBs may be queued by submitting an URB to an endpoint before
* previous ones complete. This can maximize bandwidth utilization by
* letting the USB controller start work on the next URB without any
* delay to report completion (scheduling and processing an interrupt)
* and then submit that next request.
......@@ -128,16 +128,19 @@ struct urb * usb_get_urb(struct urb *urb)
*
* Reserved Bandwidth Transfers:
*
* Periodic URBs (interrupt or isochronous) are completed repeatedly,
* Periodic URBs (interrupt or isochronous) are performed repeatedly.
*
* For interrupt requests this is (currently) automagically done
* until the original request is aborted. When the completion callback
* indicates the URB has been unlinked (with a special status code),
* control of that URB returns to the device driver. Otherwise, the
* completion handler does not control the URB, and should not change
* any of its fields.
*
* Note that isochronous URBs should be submitted in a "ring" data
* structure (using urb->next) to ensure that they are resubmitted
* appropriately.
* For isochronous requests, the completion handler is expected to
* submit an urb, typically resubmitting its parameter, until drivers
* stop wanting data transfers. (For example, audio playback might have
* finished, or a webcam turned off.)
*
* If the USB subsystem can't reserve sufficient bandwidth to perform
* the periodic request, and bandwidth reservation is being done for
......@@ -274,17 +277,18 @@ int usb_submit_urb(struct urb *urb, int mem_flags)
/* enforce simple/standard policy */
allowed = USB_ASYNC_UNLINK; // affects later unlinks
allowed |= USB_NO_FSBR; // only affects UHCI
switch (temp) {
case PIPE_CONTROL:
allowed |= USB_DISABLE_SPD;
break;
case PIPE_BULK:
allowed |= USB_DISABLE_SPD | USB_QUEUE_BULK
| USB_ZERO_PACKET | URB_NO_INTERRUPT;
break;
case PIPE_INTERRUPT:
allowed |= USB_DISABLE_SPD;
allowed |= URB_NO_INTERRUPT;
if (is_out)
allowed |= USB_ZERO_PACKET;
/* FALLTHROUGH */
case PIPE_CONTROL:
allowed |= USB_NO_FSBR; /* only affects UHCI */
/* FALLTHROUGH */
default: /* all non-iso endpoints */
if (!is_out)
allowed |= URB_SHORT_NOT_OK;
break;
case PIPE_ISOCHRONOUS:
allowed |= USB_ISO_ASAP;
......
......@@ -170,7 +170,7 @@ static void ehci_urb_complete (
/* cleanse status if we saw no error */
if (likely (urb->status == -EINPROGRESS)) {
if (urb->actual_length != urb->transfer_buffer_length
&& (urb->transfer_flags & USB_DISABLE_SPD))
&& (urb->transfer_flags & URB_SHORT_NOT_OK))
urb->status = -EREMOTEIO;
else
urb->status = 0;
......@@ -202,7 +202,7 @@ static void ehci_urb_done (
if (likely (urb->status == -EINPROGRESS)) {
if (urb->actual_length != urb->transfer_buffer_length
&& (urb->transfer_flags & USB_DISABLE_SPD))
&& (urb->transfer_flags & URB_SHORT_NOT_OK))
urb->status = -EREMOTEIO;
else
urb->status = 0;
......@@ -793,7 +793,7 @@ submit_async (
last_qtd->hw_next = hw_next;
/* previous urb allows short rx? maybe optimize. */
if (!(last_qtd->urb->transfer_flags & USB_DISABLE_SPD)
if (!(last_qtd->urb->transfer_flags & URB_SHORT_NOT_OK)
&& (epnum & 0x10)) {
// only the last QTD for now
last_qtd->hw_alt_next = hw_next;
......
......@@ -726,10 +726,6 @@ static void td_done (struct urb *urb, struct td *td)
int dlen = 0;
cc = (tdPSW >> 12) & 0xF;
if (! ((urb->transfer_flags & USB_DISABLE_SPD)
&& (cc == TD_DATAUNDERRUN)))
cc = TD_CC_NOERROR;
if (usb_pipeout (urb->pipe))
dlen = urb->iso_frame_desc [td->index].length;
else
......@@ -758,9 +754,9 @@ static void td_done (struct urb *urb, struct td *td)
usb_pipeendpoint (urb->pipe),
usb_pipeout (urb->pipe));
/* update packet status if needed (short may be ok) */
if (((urb->transfer_flags & USB_DISABLE_SPD) != 0
&& cc == TD_DATAUNDERRUN))
/* update packet status if needed (short is normally ok) */
if (cc == TD_DATAUNDERRUN
&& !(urb->transfer_flags & URB_SHORT_NOT_OK))
cc = TD_CC_NOERROR;
if (cc != TD_CC_NOERROR) {
spin_lock (&urb->lock);
......
......@@ -491,7 +491,7 @@ static int uhci_fixup_toggle(struct urb *urb, unsigned int toggle)
}
/* This function will append one URB's QH to another URB's QH. This is for */
/* USB_QUEUE_BULK support for bulk transfers and soon implicitily for */
/* queuing bulk transfers and soon implicitily for */
/* control transfers */
static void uhci_append_queued_urb(struct uhci_hcd *uhci, struct urb *eurb, struct urb *urb)
{
......@@ -840,7 +840,7 @@ static int uhci_submit_control(struct uhci_hcd *uhci, struct urb *urb)
*/
destination ^= (USB_PID_SETUP ^ usb_packetid(urb->pipe));
if (!(urb->transfer_flags & USB_DISABLE_SPD))
if (!(urb->transfer_flags & URB_SHORT_NOT_OK))
status |= TD_CTRL_SPD;
/*
......@@ -1006,7 +1006,7 @@ static int uhci_result_control(struct uhci_hcd *uhci, struct urb *urb)
/* Check to see if we received a short packet */
if (uhci_actual_length(td_status(td)) < uhci_expected_length(td_token(td))) {
if (urb->transfer_flags & USB_DISABLE_SPD) {
if (urb->transfer_flags & URB_SHORT_NOT_OK) {
ret = -EREMOTEIO;
goto err;
}
......@@ -1128,7 +1128,7 @@ static int uhci_result_interrupt(struct uhci_hcd *uhci, struct urb *urb)
goto td_error;
if (uhci_actual_length(td_status(td)) < uhci_expected_length(td_token(td))) {
if (urb->transfer_flags & USB_DISABLE_SPD) {
if (urb->transfer_flags & URB_SHORT_NOT_OK) {
ret = -EREMOTEIO;
goto err;
} else
......@@ -1210,7 +1210,7 @@ static int uhci_submit_bulk(struct uhci_hcd *uhci, struct urb *urb, struct urb *
/* 3 errors */
status = TD_CTRL_ACTIVE | uhci_maxerr(3);
if (!(urb->transfer_flags & USB_DISABLE_SPD))
if (!(urb->transfer_flags & URB_SHORT_NOT_OK))
status |= TD_CTRL_SPD;
/*
......@@ -1276,7 +1276,7 @@ static int uhci_submit_bulk(struct uhci_hcd *uhci, struct urb *urb, struct urb *
/* Always assume breadth first */
uhci_insert_tds_in_qh(qh, urb, 1);
if (urb->transfer_flags & USB_QUEUE_BULK && eurb)
if (eurb)
uhci_append_queued_urb(uhci, eurb, urb);
else
uhci_insert_qh(uhci, uhci->skel_bulk_qh, urb);
......@@ -1470,10 +1470,6 @@ static int uhci_urb_enqueue(struct usb_hcd *hcd, struct urb *urb, int mem_flags)
spin_lock_irqsave(&uhci->urb_list_lock, flags);
eurb = uhci_find_urb_ep(uhci, urb);
if (eurb && !(urb->transfer_flags & USB_QUEUE_BULK)) {
spin_unlock_irqrestore(&uhci->urb_list_lock, flags);
return -ENXIO;
}
if (!uhci_alloc_urb_priv(uhci, urb)) {
spin_unlock_irqrestore(&uhci->urb_list_lock, flags);
......@@ -1482,10 +1478,15 @@ static int uhci_urb_enqueue(struct usb_hcd *hcd, struct urb *urb, int mem_flags)
switch (usb_pipetype(urb->pipe)) {
case PIPE_CONTROL:
if (eurb)
ret = -ENXIO; /* no control queueing yet */
else
ret = uhci_submit_control(uhci, urb);
break;
case PIPE_INTERRUPT:
if (urb->bandwidth == 0) { /* not yet checked/allocated */
if (eurb)
ret = -ENXIO; /* no interrupt queueing yet */
else if (urb->bandwidth == 0) { /* not yet checked/allocated */
bustime = usb_check_bandwidth(urb->dev, urb);
if (bustime < 0)
ret = bustime;
......
......@@ -593,7 +593,6 @@ static int se401_start_stream(struct usb_se401 *se401)
se401->sbuf[i].data, SE401_PACKETSIZE,
se401_video_irq,
se401);
urb->transfer_flags |= USB_QUEUE_BULK;
se401->urb[i]=urb;
......
......@@ -776,7 +776,6 @@ static int stv680_start_stream (struct usb_stv *stv680)
stv680->sbuf[i].data, stv680->rawbufsize,
stv680_video_irq, stv680);
urb->timeout = PENCAM_TIMEOUT * 2;
urb->transfer_flags |= USB_QUEUE_BULK;
stv680->urb[i] = urb;
err = usb_submit_urb (stv680->urb[i], GFP_KERNEL);
if (err)
......
......@@ -1317,9 +1317,6 @@ static void rx_submit (struct usbnet *dev, struct urb *urb, int flags)
usb_rcvbulkpipe (dev->udev, dev->driver_info->in),
skb->data, size, rx_complete, skb);
urb->transfer_flags |= USB_ASYNC_UNLINK;
#ifdef REALLY_QUEUE
urb->transfer_flags |= USB_QUEUE_BULK;
#endif
#if 0
// Idle-but-posted reads with UHCI really chew up
// PCI bandwidth unless FSBR is disabled
......@@ -1802,9 +1799,6 @@ static int usbnet_start_xmit (struct sk_buff *skb, struct net_device *net)
usb_sndbulkpipe (dev->udev, info->out),
skb->data, skb->len, tx_complete, skb);
urb->transfer_flags |= USB_ASYNC_UNLINK;
#ifdef REALLY_QUEUE
urb->transfer_flags |= USB_QUEUE_BULK;
#endif
// FIXME urb->timeout = ... jiffies ... ;
spin_lock_irqsave (&dev->txq.lock, flags);
......
......@@ -171,8 +171,6 @@ static int empeg_open (struct usb_serial_port *port, struct file *filp)
empeg_read_bulk_callback,
port);
port->read_urb->transfer_flags |= USB_QUEUE_BULK;
result = usb_submit_urb(port->read_urb, GFP_KERNEL);
if (result)
......@@ -270,8 +268,6 @@ static int empeg_write (struct usb_serial_port *port, int from_user, const unsig
empeg_write_bulk_callback,
port);
urb->transfer_flags |= USB_QUEUE_BULK;
/* send it down the pipe */
status = usb_submit_urb(urb, GFP_ATOMIC);
if (status) {
......@@ -424,8 +420,6 @@ static void empeg_read_bulk_callback (struct urb *urb)
empeg_read_bulk_callback,
port);
port->read_urb->transfer_flags |= USB_QUEUE_BULK;
result = usb_submit_urb(port->read_urb, GFP_ATOMIC);
if (result)
......
......@@ -1460,9 +1460,6 @@ static void send_more_port_data(struct edgeport_serial *edge_serial, struct edge
usb_sndbulkpipe(edge_serial->serial->dev, edge_serial->bulk_out_endpoint),
buffer, count+2, edge_bulk_out_data_callback, edge_port);
/* set the USB_BULK_QUEUE flag so that we can shove a bunch of urbs at once down the pipe */
urb->transfer_flags |= USB_QUEUE_BULK;
urb->dev = edge_serial->serial->dev;
status = usb_submit_urb(urb, GFP_ATOMIC);
if (status) {
......@@ -2488,9 +2485,6 @@ static int write_cmd_usb (struct edgeport_port *edge_port, unsigned char *buffer
usb_sndbulkpipe(edge_serial->serial->dev, edge_serial->bulk_out_endpoint),
buffer, length, edge_bulk_out_cmd_callback, edge_port);
/* set the USB_BULK_QUEUE flag so that we can shove a bunch of urbs at once down the pipe */
urb->transfer_flags |= USB_QUEUE_BULK;
edge_port->commandPending = TRUE;
status = usb_submit_urb(urb, GFP_ATOMIC);
......
......@@ -311,7 +311,6 @@ static int ir_open (struct usb_serial_port *port, struct file *filp)
port->read_urb->transfer_buffer_length,
ir_read_bulk_callback,
port);
port->read_urb->transfer_flags = USB_QUEUE_BULK;
result = usb_submit_urb(port->read_urb, GFP_KERNEL);
if (result)
err("%s - failed submitting read urb, error %d", __FUNCTION__, result);
......@@ -389,9 +388,7 @@ static int ir_write (struct usb_serial_port *port, int from_user, const unsigned
ir_write_bulk_callback,
port);
port->write_urb->transfer_flags
= USB_QUEUE_BULK
| USB_ZERO_PACKET;
port->write_urb->transfer_flags = USB_ZERO_PACKET;
result = usb_submit_urb (port->write_urb, GFP_ATOMIC);
if (result)
......@@ -501,8 +498,6 @@ static void ir_read_bulk_callback (struct urb *urb)
ir_read_bulk_callback,
port);
port->read_urb->transfer_flags = USB_QUEUE_BULK;
result = usb_submit_urb(port->read_urb, GFP_ATOMIC);
if (result)
......@@ -598,9 +593,7 @@ static void ir_set_termios (struct usb_serial_port *port, struct termios *old_te
ir_write_bulk_callback,
port);
port->write_urb->transfer_flags
= USB_QUEUE_BULK
| USB_ZERO_PACKET;
port->write_urb->transfer_flags = USB_ZERO_PACKET;
result = usb_submit_urb (port->write_urb, GFP_KERNEL);
if (result)
......
......@@ -391,7 +391,6 @@ static int klsi_105_open (struct usb_serial_port *port, struct file *filp)
port->read_urb->transfer_buffer_length,
klsi_105_read_bulk_callback,
port);
port->read_urb->transfer_flags |= USB_QUEUE_BULK;
rc = usb_submit_urb(port->read_urb, GFP_KERNEL);
if (rc) {
......@@ -537,8 +536,6 @@ static int klsi_105_write (struct usb_serial_port *port, int from_user,
URB_TRANSFER_BUFFER_SIZE,
klsi_105_write_bulk_callback,
port);
urb->transfer_flags |= USB_QUEUE_BULK;
/* send the data out the bulk port */
result = usb_submit_urb(urb, GFP_ATOMIC);
......
......@@ -390,7 +390,6 @@ static int visor_write (struct usb_serial_port *port, int from_user, const unsig
port->bulk_out_endpointAddress),
buffer, count,
visor_write_bulk_callback, port);
urb->transfer_flags |= USB_QUEUE_BULK;
/* send it down the pipe */
status = usb_submit_urb(urb, GFP_ATOMIC);
......
......@@ -466,7 +466,7 @@ const struct usb_device_id *usb_match_id(struct usb_device *dev,
* than changeable ("unstable") ones like bus numbers or device addresses.
*
* With a partial exception for devices connected to USB 2.0 root hubs, these
* identifiers are also predictable: so long as the device tree isn't changed,
* identifiers are also predictable. So long as the device tree isn't changed,
* plugging any USB device into a given hub port always gives it the same path.
* Because of the use of "companion" controllers, devices connected to ports on
* USB 2.0 root hubs (EHCI host controllers) will get one path ID if they are
......@@ -722,16 +722,14 @@ extern void usb_deregister_dev(int num_minors, int start_minor);
/*
* urb->transfer_flags:
*
* FIXME should be URB_* flags
* FIXME should _all_ be URB_* flags
*/
#define USB_DISABLE_SPD 0x0001
#define USB_ISO_ASAP 0x0002
#define USB_ASYNC_UNLINK 0x0008
#define USB_QUEUE_BULK 0x0010
#define USB_NO_FSBR 0x0020
#define URB_SHORT_NOT_OK 0x0001 /* report short reads as errors */
#define USB_ISO_ASAP 0x0002 /* iso-only, urb->start_frame ignored */
#define USB_ASYNC_UNLINK 0x0008 /* usb_unlink_urb() returns asap */
#define USB_NO_FSBR 0x0020 /* UHCI-specific */
#define USB_ZERO_PACKET 0x0040 /* Finish bulk OUTs with short packet */
#define URB_NO_INTERRUPT 0x0080 /* HINT: no non-error interrupt needed */
/* ... less overhead for QUEUE_BULK */
#define USB_TIMEOUT_KILLED 0x1000 /* only set by HCD! */
struct usb_iso_packet_descriptor {
......@@ -777,9 +775,9 @@ typedef void (*usb_complete_t)(struct urb *);
* @actual_length: This is read in non-iso completion functions, and
* it tells how many bytes (out of transfer_buffer_length) were
* transferred. It will normally be the same as requested, unless
* either an error was reported or a short read was performed and
* the USB_DISABLE_SPD transfer flag was used to say that such
* short reads are not errors.
* either an error was reported or a short read was performed.
* The URB_SHORT_NOT_OK transfer flag may be used to make such
* short reads be reported as errors.
* @setup_packet: Only used for control transfers, this points to eight bytes
* of setup data. Control transfers always start by sending this data
* to the device. Then transfer_buffer is read or written, if needed.
......@@ -814,14 +812,10 @@ typedef void (*usb_complete_t)(struct urb *);
*
* All non-isochronous URBs must also initialize
* transfer_buffer and transfer_buffer_length. They may provide the
* USB_DISABLE_SPD transfer flag, indicating that short reads are
* not to be treated as errors.
* URB_SHORT_NOT_OK transfer flag, indicating that short reads are
* to be treated as errors.
*
* Bulk URBs may pass the USB_QUEUE_BULK transfer flag, telling the host
* controller driver never to report an error if several bulk requests get
* queued to the same endpoint. Such queueing supports more efficient use
* of bus bandwidth, minimizing delays due to interrupts and scheduling,
* if the host controller hardware is smart enough. Bulk URBs can also
* Bulk URBs may
* use the USB_ZERO_PACKET transfer flag, indicating that bulk OUT transfers
* should always terminate with a short packet, even if it means adding an
* extra zero length packet.
......@@ -853,7 +847,7 @@ typedef void (*usb_complete_t)(struct urb *);
* the quality of service is only "best effort". Callers provide specially
* allocated URBs, with number_of_packets worth of iso_frame_desc structures
* at the end. Each such packet is an individual ISO transfer. Isochronous
* URBs are normally queued (no flag like USB_BULK_QUEUE is needed) so that
* URBs are normally queued, submitted by drivers to arrange that
* transfers are at least double buffered, and then explicitly resubmitted
* in completion handlers, so
* that data (such as audio or video) streams at as constant a rate as the
......@@ -892,7 +886,7 @@ struct urb
struct usb_device *dev; /* (in) pointer to associated device */
unsigned int pipe; /* (in) pipe information */
int status; /* (return) non-ISO status */
unsigned int transfer_flags; /* (in) USB_DISABLE_SPD | ...*/
unsigned int transfer_flags; /* (in) URB_SHORT_NOT_OK | ...*/
void *transfer_buffer; /* (in) associated data buffer */
int transfer_buffer_length; /* (in) data buffer length */
int actual_length; /* (return) actual transfer length */
......
......@@ -78,9 +78,8 @@ struct usbdevfs_connectinfo {
unsigned char slow;
};
#define USBDEVFS_URB_DISABLE_SPD 1
#define USBDEVFS_URB_SHORT_NOT_OK 1
#define USBDEVFS_URB_ISO_ASAP 2
#define USBDEVFS_URB_QUEUE_BULK 0x10
#define USBDEVFS_URB_TYPE_ISO 0
#define USBDEVFS_URB_TYPE_INTERRUPT 1
......
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