tty_port,usb-console: Fix usb serial console open/close regression

Commit e1108a63e10d344284011cccc06328b2cd3e5da3 ("usb_serial: Use the
shutdown() operation") breaks the ability to use a usb console
starting in 2.6.33.  This was observed when using
console=ttyUSB0,115200 as a boot argument with an FTDI device.  The
error is:

ftdi_sio ttyUSB0: ftdi_submit_read_urb - failed submitting read urb, error -22

The handling of the ASYNCB_INITIALIZED changed in 2.6.32 such that in
tty_port_shutdown() it always clears the flag if it is set.  The fix
is to add a variable to the tty_port struct to indicate when the tty
port is a console.

CC: Alan Cox <alan@linux.intel.com>
CC: Alan Stern <stern@rowland.harvard.edu>
CC: Oliver Neukum <oliver@neukum.org>
CC: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Jason Wessel <jason.wessel@windriver.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>

3 files changed, 3 insertions, 1 deletions

diff --git a/drivers/char/tty_port.c b/drivers/char/tty_port.c
index be492dd66437..a3bd1d0b66cf 100644
--- a/drivers/char/tty_port.c
+++ b/drivers/char/tty_port.c
@@ -119,7 +119,7 @@ EXPORT_SYMBOL(tty_port_tty_set);
 static void tty_port_shutdown(struct tty_port *port)
 {
         mutex_lock(&port->mutex);
-        if (port->ops->shutdown &&
+        if (port->ops->shutdown && !port->console &&
                 test_and_clear_bit(ASYNCB_INITIALIZED, &port->flags))
                         port->ops->shutdown(port);
         mutex_unlock(&port->mutex);
diff --git a/drivers/usb/serial/console.c b/drivers/usb/serial/console.c
index b22ac3258523..f347da2ef00a 100644
--- a/drivers/usb/serial/console.c
+++ b/drivers/usb/serial/console.c
@@ -181,6 +181,7 @@ static int usb_console_setup(struct console *co, char *options)
         /* The console is special in terms of closing the device so
          * indicate this port is now acting as a system console. */
         port->console = 1;
+        port->port.console = 1;
 
         mutex_unlock(&serial->disc_mutex);
         return retval;
diff --git a/include/linux/tty.h b/include/linux/tty.h
index 593228a520e1..4409967db0c4 100644
--- a/include/linux/tty.h
+++ b/include/linux/tty.h
@@ -224,6 +224,7 @@ struct tty_port {
         wait_queue_head_t       close_wait;     /* Close waiters */
         wait_queue_head_t       delta_msr_wait; /* Modem status change */
         unsigned long           flags;          /* TTY flags ASY_*/
+        unsigned char           console:1;      /* port is a console */
         struct mutex            mutex;          /* Locking */
         struct mutex            buf_mutex;      /* Buffer alloc lock */
         unsigned char           *xmit_buf;      /* Optional buffer */