From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: From: Greg Kroah-Hartman To: linux-kernel@vger.kernel.org Cc: Greg Kroah-Hartman , stable@vger.kernel.org, William Gulland , Alan Stern Subject: [ 10/23] usb: Clear both buffers when clearing a control transfer TT buffer. Date: Fri, 2 Aug 2013 18:23:23 +0800 Message-Id: <20130802102037.658840405@linuxfoundation.org> In-Reply-To: <20130802102036.180660415@linuxfoundation.org> References: <20130802102036.180660415@linuxfoundation.org> Sender: linux-kernel-owner@vger.kernel.org List-ID: 3.0-stable review patch. If anyone has any objections, please let me know. ------------------ From: William Gulland commit 2c7b871b9102c497ba8f972aa5d38532f05b654d upstream. 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 Acked-by: Alan Stern Signed-off-by: Greg Kroah-Hartman --- drivers/usb/core/hub.c | 9 +++++++++ 1 file changed, 9 insertions(+) --- a/drivers/usb/core/hub.c +++ b/drivers/usb/core/hub.c @@ -463,6 +463,15 @@ resubmit: 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);