releases/4.4.44/usb-serial-ch341-fix-open-and-resume-after-b0.patch

   1 From a20047f36e2f6a1eea4f1fd261aaa55882369868 Mon Sep 17 00:00:00 2001
   2 From: Johan Hovold <johan@kernel.org>
   3 Date: Fri, 6 Jan 2017 19:15:11 +0100
   4 Subject: USB: serial: ch341: fix open and resume after B0
   5
   6 From: Johan Hovold <johan@kernel.org>
   7
   8 commit a20047f36e2f6a1eea4f1fd261aaa55882369868 upstream.
   9
  10 The private baud_rate variable is used to configure the port at open and
  11 reset-resume and must never be set to (and left at) zero or reset-resume
  12 and all further open attempts will fail.
  13
  14 Fixes: aa91def41a7b ("USB: ch341: set tty baud speed according to tty struct")
  15 Fixes: 664d5df92e88 ("USB: usb-serial ch341: support for DTR/RTS/CTS")
  16 Signed-off-by: Johan Hovold <johan@kernel.org>
  17 Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
  18
  19 ---
  20  drivers/usb/serial/ch341.c |    3 +--
  21  1 file changed, 1 insertion(+), 2 deletions(-)
  22
  23 --- a/drivers/usb/serial/ch341.c
  24 +++ b/drivers/usb/serial/ch341.c
  25 @@ -361,12 +361,11 @@ static void ch341_set_termios(struct tty
  26
  27         baud_rate = tty_get_baud_rate(tty);
  28
  29 -       priv->baud_rate = baud_rate;
  30 -
  31         if (baud_rate) {
  32                 spin_lock_irqsave(&priv->lock, flags);
  33                 priv->line_control |= (CH341_BIT_DTR | CH341_BIT_RTS);
  34                 spin_unlock_irqrestore(&priv->lock, flags);
  35 +               priv->baud_rate = baud_rate;
  36                 ch341_set_baudrate(port->serial->dev, priv);
  37         } else {
  38                 spin_lock_irqsave(&priv->lock, flags);