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usb: Clear both buffers when clearing a control transfer TT buffer. 

Control transfers have both IN and OUT (or SETUP) packets, so when
clearing TT buffers for a control transfer it's necessary to send
two HUB_CLEAR_TT_BUFFER requests to the hub.

Signed-off-by: William Gulland <wgulland@google.com>
Acked-by: Alan Stern <stern@rowland.harvard.edu>
Cc: stable <stable@vger.kernel.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
This commit is contained in:
William Gulland 2013-06-27 16:10:20 -07:00 committed by Greg Kroah-Hartman
parent 172d934c92
commit 2c7b871b91
1 changed files with 9 additions and 0 deletions
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9
drivers/usb/core/hub.c
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@ -668,6 +668,15 @@ static void hub_irq(struct urb *urb)
static inline int
hub_clear_tt_buffer (struct usb_device *hdev, u16 devinfo, u16 tt)
{
/* Need to clear both directions for control ep */
if (((devinfo >> 11) & USB_ENDPOINT_XFERTYPE_MASK) ==
USB_ENDPOINT_XFER_CONTROL) {
int status = usb_control_msg(hdev, usb_sndctrlpipe(hdev, 0),
HUB_CLEAR_TT_BUFFER, USB_RT_PORT,
devinfo ^ 0x8000, tt, NULL, 0, 1000);
if (status)
return status;
}
return usb_control_msg(hdev, usb_sndctrlpipe(hdev, 0),
HUB_CLEAR_TT_BUFFER, USB_RT_PORT, devinfo,
tt, NULL, 0, 1000);