From 27b351c5546008c640b3e65152f60ca74b3706f1 Mon Sep 17 00:00:00 2001 From: Bill Pemberton Date: Wed, 13 Mar 2013 09:50:15 -0400 Subject: [PATCH] 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 Signed-off-by: Greg Kroah-Hartman --- drivers/usb/serial/quatech2.c | 7 +++++-- 1 file changed, 5 insertions(+), 2 deletions(-) diff --git a/drivers/usb/serial/quatech2.c b/drivers/usb/serial/quatech2.c index 00e6c9bac8a3..d643a4d4d770 100644 --- a/drivers/usb/serial/quatech2.c +++ b/drivers/usb/serial/quatech2.c @@ -661,7 +661,9 @@ void qt2_process_read_urb(struct urb *urb) __func__); break; } - tty_flip_buffer_push(&port->port); + + if (port_priv->is_open) + tty_flip_buffer_push(&port->port); newport = *(ch + 3); @@ -704,7 +706,8 @@ void qt2_process_read_urb(struct urb *urb) tty_insert_flip_string(&port->port, ch, 1); } - tty_flip_buffer_push(&port->port); + if (port_priv->is_open) + tty_flip_buffer_push(&port->port); } static void qt2_write_bulk_callback(struct urb *urb) -- 2.39.5