tree 766c1d602d3942be6ba24086c7752926f70197c5
parent 3f8bc5e4da29c7e05edeca6b475abb4fb01a5a13
author Bill Pemberton <wfp5p@virginia.edu> 1363182615 -0400
committer Greg Kroah-Hartman <gregkh@linuxfoundation.org> 1363203167 -0700

USB: quatech2: only write to the tty if the port is open.

The commit 2e124b4a390ca85325fae75764bef92f0547fa25 removed the checks
that prevented qt2_process_read_urb() from trying to put chars into
ttys that weren't actually opened.  This resulted in 'tty is NULL'
warnings from flush_to_ldisc() when the device was used.

The devices use just one read urb for all ports.  As a result
qt2_process_read_urb() may be called with the current port set to a
port number that has not been opened.  Add a check if the port is open
before calling tty_flip_buffer_push().

Signed-off-by: Bill Pemberton <wfp5p@virginia.edu>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>