Re: Patch "USB: serial: ch341: fix resume after reset" has been added to the 4.4-stable tree

[Greg KH <gregkh@linuxfoundation.org>]

On Tue, Jan 17, 2017 at 03:22:05PM +0100, Johan Hovold wrote:
> On Tue, Jan 17, 2017 at 02:04:41PM +0100, Greg Kroah-Hartman wrote:
> > 
> > This is a note to let you know that I've just added the patch titled
> > 
> >     USB: serial: ch341: fix resume after reset
> > 
> > to the 4.4-stable tree which can be found at:
> >     http://www.kernel.org/git/?p=linux/kernel/git/stable/stable-queue.git;a=summary
> > 
> > The filename of the patch is:
> >      usb-serial-ch341-fix-resume-after-reset.patch
> > and it can be found in the queue-4.4 subdirectory.
> > 
> > If you, or anyone else, feels it should not be added to the stable tree,
> > please let <stable@vger.kernel.org> know about it.
> > 
> > 
> > From ce5e292828117d1b71cbd3edf9e9137cf31acd30 Mon Sep 17 00:00:00 2001
> > From: Johan Hovold <johan@kernel.org>
> > Date: Fri, 6 Jan 2017 19:15:14 +0100
> > Subject: USB: serial: ch341: fix resume after reset
> > 
> > From: Johan Hovold <johan@kernel.org>
> > 
> > commit ce5e292828117d1b71cbd3edf9e9137cf31acd30 upstream.
> > 
> > Fix reset-resume handling which failed to resubmit the read and
> > interrupt URBs, thereby leaving a port that was open before suspend in a
> > broken state until closed and reopened.
> > 
> > Fixes: 1ded7ea47b88 ("USB: ch341 serial: fix port number changed after resume")
> > Fixes: 2bfd1c96a9fb ("USB: serial: ch341: remove reset_resume callback")
> > Signed-off-by: Johan Hovold <johan@kernel.org>
> > Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
> > 
> > ---
> >  drivers/usb/serial/ch341.c |   17 +++++++++++++----
> >  1 file changed, 13 insertions(+), 4 deletions(-)
> > 
> > --- a/drivers/usb/serial/ch341.c
> > +++ b/drivers/usb/serial/ch341.c
> > @@ -538,14 +538,23 @@ static int ch341_tiocmget(struct tty_str
> >  
> >  static int ch341_reset_resume(struct usb_serial *serial)
> >  {
> > -	struct ch341_private *priv;
> > -
> > -	priv = usb_get_serial_port_data(serial->port[0]);
> > +	struct usb_serial_port *port = serial->port[0];
> > +	struct ch341_private *priv = usb_get_serial_port_data(port);
> > +	int ret;
> >  
> >  	/* reconfigure ch341 serial port after bus-reset */
> >  	ch341_configure(serial->dev, priv);
> >  
> > -	return 0;
> > +	if (tty_port_initialized(&port->port)) {
> 
> Note that this needs to be
> 
> 	if (test_bit(ASYNCB_INITIALIZED, &port->port.flags))
> 
> prior to commit d41861ca19c9 ("tty: Replace ASYNC_INITIALIZED bit and
> update atomically") that went into 4.7.
> 
> I'll send a backport.

Many thanks, my build system just hit this error.  I'll drop this patch
for now.

greg k-h