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USB: xhci: Deal with stalled endpoints.

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When an endpoint on a device under an xHCI host controller stalls, the
host controller driver must let the hardware know that the USB core has
successfully cleared the halt condition.  The HCD submits a Reset Endpoint
Command, which will clear the toggle bit for USB 2.0 devices, and set the
sequence number to zero for USB 3.0 devices.

The xHCI urb_enqueue will accept new URBs while the endpoint is halted,
and will queue them to the hardware rings.  However, the endpoint doorbell
will not be rung until the Reset Endpoint Command completes.

Don't queue a reset endpoint command for root hubs.  khubd clears halt
conditions on the roothub during the initialization process, but the roothub
isn't a real device, so the xHCI host controller doesn't need to know about the
cleared halt.

Signed-off-by: Sarah Sharp <sarah.a.sharp@linux.intel.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
This commit is contained in:
Sarah Sharp
2009-07-27 12:03:15 -07:00
committed by Greg Kroah-Hartman
parent f9dc68fe7a
commit a1587d97ce
4 changed files with 85 additions and 4 deletions
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1
drivers/usb/host/xhci-pci.c
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@@ -117,6 +117,7 @@ static const struct hc_driver xhci_pci_hc_driver = {
.free_dev = xhci_free_dev,
.add_endpoint = xhci_add_endpoint,
.drop_endpoint = xhci_drop_endpoint,
.endpoint_reset = xhci_endpoint_reset,
.check_bandwidth = xhci_check_bandwidth,
.reset_bandwidth = xhci_reset_bandwidth,
.address_device = xhci_address_device,