tty_port: add "tty_port_open" helper
For the moment this just moves the USB logic over and fixes the 'what if
we open and hangup at the same time' race noticed by Oliver Neukum.
Signed-off-by: Alan Cox <alan@linux.intel.com>
Cc: Alan Stern <stern@rowland.harvard.edu>
Cc: Oliver Neukum <oliver@neukum.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
diff --git a/drivers/usb/serial/usb-serial.c b/drivers/usb/serial/usb-serial.c
index bd3fa7f..b0649d9 100644
--- a/drivers/usb/serial/usb-serial.c
+++ b/drivers/usb/serial/usb-serial.c
@@ -247,43 +247,33 @@
return retval;
}
-static int serial_open(struct tty_struct *tty, struct file *filp)
+static int serial_activate(struct tty_port *tport, struct tty_struct *tty)
{
- struct usb_serial_port *port = tty->driver_data;
+ struct usb_serial_port *port =
+ container_of(tport, struct usb_serial_port, port);
struct usb_serial *serial = port->serial;
int retval;
- dbg("%s - port %d", __func__, port->number);
-
- spin_lock_irq(&port->port.lock);
- if (!tty_hung_up_p(filp))
- ++port->port.count;
- spin_unlock_irq(&port->port.lock);
- tty_port_tty_set(&port->port, tty);
-
- /* Do the device-specific open only if the hardware isn't
- * already initialized.
- */
- if (!test_bit(ASYNCB_INITIALIZED, &port->port.flags)) {
- if (mutex_lock_interruptible(&port->mutex))
- return -ERESTARTSYS;
- mutex_lock(&serial->disc_mutex);
- if (serial->disconnected)
- retval = -ENODEV;
- else
- retval = port->serial->type->open(tty, port);
- mutex_unlock(&serial->disc_mutex);
- mutex_unlock(&port->mutex);
- if (retval)
- return retval;
- set_bit(ASYNCB_INITIALIZED, &port->port.flags);
- }
-
- /* Now do the correct tty layer semantics */
- retval = tty_port_block_til_ready(&port->port, tty, filp);
+ if (mutex_lock_interruptible(&port->mutex))
+ return -ERESTARTSYS;
+ mutex_lock(&serial->disc_mutex);
+ if (serial->disconnected)
+ retval = -ENODEV;
+ else
+ retval = port->serial->type->open(tty, port);
+ mutex_unlock(&serial->disc_mutex);
+ mutex_unlock(&port->mutex);
return retval;
}
+static int serial_open(struct tty_struct *tty, struct file *filp)
+{
+ struct usb_serial_port *port = tty->driver_data;
+
+ dbg("%s - port %d", __func__, port->number);
+ return tty_port_open(&port->port, tty, filp);
+}
+
/**
* serial_down - shut down hardware
* @port: port to shut down
@@ -725,6 +715,7 @@
static const struct tty_port_operations serial_port_ops = {
.carrier_raised = serial_carrier_raised,
.dtr_rts = serial_dtr_rts,
+ .activate = serial_activate,
};
int usb_serial_probe(struct usb_interface *interface,
