From: William Gulland Date: Thu, 27 Jun 2013 23:10:20 +0000 (-0700) Subject: usb: Clear both buffers when clearing a control transfer TT buffer. X-Git-Tag: firefly_0821_release~6453^2~1303 X-Git-Url: http://demsky.eecs.uci.edu/git/?a=commitdiff_plain;h=889ba7bc28e5db5da40f648c91678dcc2d2837fd;p=firefly-linux-kernel-4.4.55.git usb: Clear both buffers when clearing a control transfer TT buffer. 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 --- diff --git a/drivers/usb/core/hub.c b/drivers/usb/core/hub.c index feef9351463d..868ad745a500 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);