From: Bill Pemberton Date: Wed, 13 Mar 2013 13:50:15 +0000 (-0400) Subject: USB: quatech2: only write to the tty if the port is open. X-Git-Url: https://git.stricted.de/?a=commitdiff_plain;h=27b351c5546008c640b3e65152f60ca74b3706f1;p=GitHub%2Fmoto-9609%2Fandroid_kernel_motorola_exynos9610.git 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 --- 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)