USB: add urb->unlinked field
This patch (as970) adds a new urb->unlinked field, which is used to
store the status of unlinked URBs since we can't use urb->status for
that purpose any more. To help simplify the HCDs, usbcore will check
urb->unlinked before calling the completion handler; if the value is
set it will automatically override the status reported by the HCD.
Signed-off-by: Alan Stern <stern@rowland.harvard.edu>
CC: David Brownell <david-b@pacbell.net>
CC: Olav Kongas <ok@artecdesign.ee>
CC: Yoshihiro Shimoda <shimoda.yoshihiro@renesas.com>
CC: Tony Olech <tony.olech@elandigitalsystems.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
diff --git a/drivers/usb/core/hcd.c b/drivers/usb/core/hcd.c
index 22a098b..ec17fc4 100644
--- a/drivers/usb/core/hcd.c
+++ b/drivers/usb/core/hcd.c
@@ -532,8 +532,7 @@
/* any errors get returned through the urb completion */
spin_lock_irq(&hcd_root_hub_lock);
- if (urb->status == -EINPROGRESS)
- urb->status = status;
+ urb->status = status;
usb_hcd_unlink_urb_from_ep(hcd, urb);
/* This peculiar use of spinlocks echoes what real HC drivers do.
@@ -1024,6 +1023,7 @@
switch (hcd->state) {
case HC_STATE_RUNNING:
case HC_STATE_RESUMING:
+ urb->unlinked = 0;
list_add_tail(&urb->urb_list, &urb->ep->urb_list);
break;
default:
@@ -1071,9 +1071,9 @@
/* Any status except -EINPROGRESS means something already started to
* unlink this URB from the hardware. So there's no more work to do.
*/
- if (urb->status != -EINPROGRESS)
+ if (urb->unlinked)
return -EBUSY;
- urb->status = status;
+ urb->unlinked = status;
/* IRQ setup can easily be broken so that USB controllers
* never get completion IRQs ... maybe even the ones we need to
@@ -1259,6 +1259,10 @@
* (and is done using urb->hcpriv). It also released all HCD locks;
* the device driver won't cause problems if it frees, modifies,
* or resubmits this URB.
+ *
+ * If @urb was unlinked, the value of @urb->status will be overridden by
+ * @urb->unlinked. Erroneous short transfers are detected in case
+ * the HCD hasn't checked for them.
*/
void usb_hcd_giveback_urb (struct usb_hcd *hcd, struct urb *urb)
{
@@ -1266,7 +1270,9 @@
usbmon_urb_complete (&hcd->self, urb);
usb_unanchor_urb(urb);
urb->hcpriv = NULL;
- if (unlikely((urb->transfer_flags & URB_SHORT_NOT_OK) &&
+ if (unlikely(urb->unlinked))
+ urb->status = urb->unlinked;
+ else if (unlikely((urb->transfer_flags & URB_SHORT_NOT_OK) &&
urb->actual_length < urb->transfer_buffer_length &&
!urb->status))
urb->status = -EREMOTEIO;
@@ -1305,8 +1311,7 @@
list_for_each_entry (urb, &ep->urb_list, urb_list) {
int is_in;
- /* the urb may already have been unlinked */
- if (urb->status != -EINPROGRESS)
+ if (urb->unlinked)
continue;
usb_get_urb (urb);
is_in = usb_urb_dir_in(urb);