From 2c7b871b9102c497ba8f972aa5d38532f05b654d Mon Sep 17 00:00:00 2001 From: William Gulland Date: Thu, 27 Jun 2013 16:10:20 -0700 Subject: [PATCH] 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 Acked-by: Alan Stern Cc: stable Signed-off-by: Greg Kroah-Hartman --- drivers/usb/core/hub.c | 9 +++++++++ 1 file changed, 9 insertions(+) diff --git a/drivers/usb/core/hub.c b/drivers/usb/core/hub.c index c857471519e3..4a8a1d68002c 100644 --- a/drivers/usb/core/hub.c +++ b/drivers/usb/core/hub.c @@ -668,6 +668,15 @@ 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);