lk/linux-kernel-test
1
0
Fork 0
Code Issues Pull Requests Releases Wiki Activity

USB: EHCI: update toggle state for linked QHs

Browse Source 
This is an update to the "usb-ehci-update-toggle-state-for-linked-qhs"
patch.  Since an HCD's endpoint_reset method can be called in
interrupt context, it mustn't assume that interrupts are enabled or
that it can sleep.

So we revert to the original way of refreshing QHs' toggle bits.  Now
the endpoint_reset method merely clears the toggle flag in the device
structure (as was done before) and starts an async QH unlink.  When the
QH is linked again, after the unlink finishes and an URB is queued,
the qh_refresh() routine will update the QH's toggle bit.

Signed-off-by: Alan Stern <stern@rowland.harvard.edu>
Tested-by: David <david@unsolicited.net>
CC: David Brownell <david-b@pacbell.net>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
This commit is contained in:
Alan Stern
2009-06-11 14:56:22 -04:00
committed by Greg Kroah-Hartman
parent 9525dcb30f
commit a455212d19
2 changed files with 34 additions and 20 deletions
Download Patch File Download Diff File Expand all files Collapse all files

35
drivers/usb/host/ehci-hcd.c
View File

@@ -1030,12 +1030,14 @@ ehci_endpoint_reset(struct usb_hcd *hcd, struct usb_host_endpoint *ep)
struct ehci_hcd *ehci = hcd_to_ehci(hcd);
struct ehci_qh *qh;
int eptype = usb_endpoint_type(&ep->desc);
int epnum = usb_endpoint_num(&ep->desc);
int is_out = usb_endpoint_dir_out(&ep->desc);
unsigned long flags;
if (eptype != USB_ENDPOINT_XFER_BULK && eptype != USB_ENDPOINT_XFER_INT)
return;
rescan:
spin_lock_irq(&ehci->lock);
spin_lock_irqsave(&ehci->lock, flags);
qh = ep->hcpriv;
/* For Bulk and Interrupt endpoints we maintain the toggle state
@@ -1044,29 +1046,24 @@ ehci_endpoint_reset(struct usb_hcd *hcd, struct usb_host_endpoint *ep)
* the toggle bit in the QH.
*/
if (qh) {
usb_settoggle(qh->dev, epnum, is_out, 0);
if (!list_empty(&qh->qtd_list)) {
WARN_ONCE(1, "clear_halt for a busy endpoint\n");
} else if (qh->qh_state == QH_STATE_IDLE) {
qh->hw_token &= ~cpu_to_hc32(ehci, QTD_TOGGLE);
} else {
/* It's not safe to write into the overlay area
* while the QH is active. Unlink it first and
* wait for the unlink to complete.
} else if (qh->qh_state == QH_STATE_LINKED) {
/* The toggle value in the QH can't be updated
* while the QH is active. Unlink it now;
* re-linking will call qh_refresh().
*/
if (qh->qh_state == QH_STATE_LINKED) {
if (eptype == USB_ENDPOINT_XFER_BULK) {
unlink_async(ehci, qh);
} else {
intr_deschedule(ehci, qh);
(void) qh_schedule(ehci, qh);
}
if (eptype == USB_ENDPOINT_XFER_BULK) {
unlink_async(ehci, qh);
} else {
intr_deschedule(ehci, qh);
(void) qh_schedule(ehci, qh);
}
spin_unlock_irq(&ehci->lock);
schedule_timeout_uninterruptible(1);
goto rescan;
}
}
spin_unlock_irq(&ehci->lock);
spin_unlock_irqrestore(&ehci->lock, flags);
}
static int ehci_get_frame (struct usb_hcd *hcd)