diff options
| -rw-r--r-- | drivers/usb/core/hcd.c | 65 |
1 files changed, 35 insertions, 30 deletions
diff --git a/drivers/usb/core/hcd.c b/drivers/usb/core/hcd.c index dc9628c58933..ea20a3a5a9b9 100644 --- a/drivers/usb/core/hcd.c +++ b/drivers/usb/core/hcd.c @@ -633,31 +633,20 @@ static int rh_urb_enqueue (struct usb_hcd *hcd, struct urb *urb) /*-------------------------------------------------------------------------*/ -/* Asynchronous unlinks of root-hub control URBs are legal, but they - * don't do anything. Status URB unlinks must be made in process context - * with interrupts enabled. +/* Unlinks of root-hub control URBs are legal, but they don't do anything + * since these URBs always execute synchronously. */ static int usb_rh_urb_dequeue (struct usb_hcd *hcd, struct urb *urb) { - if (usb_pipeendpoint(urb->pipe) == 0) { /* Control URB */ - if (in_interrupt()) - return 0; /* nothing to do */ - - spin_lock_irq(&urb->lock); /* from usb_kill_urb */ - ++urb->reject; - spin_unlock_irq(&urb->lock); - - wait_event(usb_kill_urb_queue, - atomic_read(&urb->use_count) == 0); + unsigned long flags; - spin_lock_irq(&urb->lock); - --urb->reject; - spin_unlock_irq(&urb->lock); + if (usb_pipeendpoint(urb->pipe) == 0) { /* Control URB */ + ; /* Do nothing */ } else { /* Status URB */ if (!hcd->uses_new_polling) - del_timer_sync (&hcd->rh_timer); - local_irq_disable (); + del_timer (&hcd->rh_timer); + local_irq_save (flags); spin_lock (&hcd_root_hub_lock); if (urb == hcd->status_urb) { hcd->status_urb = NULL; @@ -667,7 +656,7 @@ static int usb_rh_urb_dequeue (struct usb_hcd *hcd, struct urb *urb) spin_unlock (&hcd_root_hub_lock); if (urb) usb_hcd_giveback_urb (hcd, urb, NULL); - local_irq_enable (); + local_irq_restore (flags); } return 0; @@ -1355,7 +1344,8 @@ done: /*-------------------------------------------------------------------------*/ /* disables the endpoint: cancels any pending urbs, then synchronizes with - * the hcd to make sure all endpoint state is gone from hardware. use for + * the hcd to make sure all endpoint state is gone from hardware, and then + * waits until the endpoint's queue is completely drained. use for * set_configuration, set_interface, driver removal, physical disconnect. * * example: a qh stored in ep->hcpriv, holding state related to endpoint @@ -1374,22 +1364,13 @@ hcd_endpoint_disable (struct usb_device *udev, struct usb_host_endpoint *ep) local_irq_disable (); - /* FIXME move most of this into message.c as part of its - * endpoint disable logic - */ - /* ep is already gone from udev->ep_{in,out}[]; no more submits */ rescan: spin_lock (&hcd_data_lock); list_for_each_entry (urb, &ep->urb_list, urb_list) { int tmp; - /* another cpu may be in hcd, spinning on hcd_data_lock - * to giveback() this urb. the races here should be - * small, but a full fix needs a new "can't submit" - * urb state. - * FIXME urb->reject should allow that... - */ + /* the urb may already have been unlinked */ if (urb->status != -EINPROGRESS) continue; usb_get_urb (urb); @@ -1431,6 +1412,30 @@ rescan: might_sleep (); if (hcd->driver->endpoint_disable) hcd->driver->endpoint_disable (hcd, ep); + + /* Wait until the endpoint queue is completely empty. Most HCDs + * will have done this already in their endpoint_disable method, + * but some might not. And there could be root-hub control URBs + * still pending since they aren't affected by the HCDs' + * endpoint_disable methods. + */ + while (!list_empty (&ep->urb_list)) { + spin_lock_irq (&hcd_data_lock); + + /* The list may have changed while we acquired the spinlock */ + urb = NULL; + if (!list_empty (&ep->urb_list)) { + urb = list_entry (ep->urb_list.prev, struct urb, + urb_list); + usb_get_urb (urb); + } + spin_unlock_irq (&hcd_data_lock); + + if (urb) { + usb_kill_urb (urb); + usb_put_urb (urb); + } + } } /*-------------------------------------------------------------------------*/ |