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USB: xhci: Fix command wait list handling.

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In the xHCI driver, configure endpoint commands that are submitted to the
hardware may involve one of two data structures.  If the configure
endpoint command is setting up a new configuration or modifying max packet
sizes, the data structures and completions are statically allocated in the
xhci_virt_device structure.  If the command is being used to set up
streams or add hub information, then the data structures are dynamically
allocated, and placed on a device command waiting list.

Break out the code to check whether a completed command is in the device
command waiting list.  Fix a subtle bug in the old code: continue
processing the command if the command isn't in the wait list.  In the old
code, if there was a command in the wait list, but it didn't match the
completed command, the completed command event would be dropped.

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 2009-09-04 10:53:15 -07:00 committed by Greg Kroah-Hartman
parent 913a8a344f
commit a50c8aa953
1 changed files with 29 additions and 17 deletions
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46
drivers/usb/host/xhci-ring.c
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@ -685,6 +685,34 @@ static void handle_reset_ep_completion(struct xhci_hcd *xhci,
}
}
/* Check to see if a command in the device's command queue matches this one.
* Signal the completion or free the command, and return 1. Return 0 if the
* completed command isn't at the head of the command list.
*/
static int handle_cmd_in_cmd_wait_list(struct xhci_hcd *xhci,
struct xhci_virt_device *virt_dev,
struct xhci_event_cmd *event)
{
struct xhci_command *command;
if (list_empty(&virt_dev->cmd_list))
return 0;
command = list_entry(virt_dev->cmd_list.next,
struct xhci_command, cmd_list);
if (xhci->cmd_ring->dequeue != command->command_trb)
return 0;
command->status =
GET_COMP_CODE(event->status);
list_del(&command->cmd_list);
if (command->completion)
complete(command->completion);
else
xhci_free_command(xhci, command);
return 1;
}
static void handle_cmd_completion(struct xhci_hcd *xhci,
struct xhci_event_cmd *event)
{
@ -724,24 +752,8 @@ static void handle_cmd_completion(struct xhci_hcd *xhci,
break;
case TRB_TYPE(TRB_CONFIG_EP):
virt_dev = xhci->devs[slot_id];
/* Check to see if a command in the device's command queue
* matches this one. Signal the completion or free the command.
*/
if (!list_empty(&virt_dev->cmd_list)) {
struct xhci_command *command;
command = list_entry(virt_dev->cmd_list.next,
struct xhci_command, cmd_list);
if (xhci->cmd_ring->dequeue == command->command_trb) {
command->status =
GET_COMP_CODE(event->status);
list_del(&command->cmd_list);
if (command->completion)
complete(command->completion);
else
xhci_free_command(xhci, command);
}
if (handle_cmd_in_cmd_wait_list(xhci, virt_dev, event))
break;
}
/*
* Configure endpoint commands can come from the USB core
* configuration or alt setting changes, or because the HW