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>
1 file changed