1 files changed, 31 insertions, 74 deletions

diff --git a/drivers/usb/serial/usb-serial.c b/drivers/usb/serial/usb-serial.c
index bd3fa7ff15b1..3873660d8217 100644
--- a/drivers/usb/serial/usb-serial.c
+++ b/drivers/usb/serial/usb-serial.c
@@ -247,96 +247,66 @@ static int serial_install(struct tty_driver *driver, struct tty_struct *tty)
         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);
+        mutex_lock(&serial->disc_mutex);
+        if (serial->disconnected)
+                retval = -ENODEV;
+        else
+                retval = port->serial->type->open(tty, port);
+        mutex_unlock(&serial->disc_mutex);
+        return retval;
+}
 
-        /* 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);
-        }
+static int serial_open(struct tty_struct *tty, struct file *filp)
+{
+        struct usb_serial_port *port = tty->driver_data;
 
-        /* Now do the correct tty layer semantics */
-        retval = tty_port_block_til_ready(&port->port, tty, filp);
-        return retval;
+        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
+ * @tport: tty port to shut down
  *
  * Shut down a USB serial port unless it is the console.  We never
- * shut down the console hardware as it will always be in use.
+ * shut down the console hardware as it will always be in use. Serialized
+ * against activate by the tport mutex and kept to matching open/close pairs
+ * of calls by the ASYNCB_INITIALIZED flag.
  */
-static void serial_down(struct usb_serial_port *port)
+static void serial_down(struct tty_port *tport)
 {
+        struct usb_serial_port *port =
+                container_of(tport, struct usb_serial_port, port);
         struct usb_serial_driver *drv = port->serial->type;
-
         /*
          * The console is magical.  Do not hang up the console hardware
          * or there will be tears.
          */
         if (port->console)
                 return;
-
-        /* Don't call the close method if the hardware hasn't been
-         * initialized.
-         */
-        if (!test_and_clear_bit(ASYNCB_INITIALIZED, &port->port.flags))
-                return;
-
-        mutex_lock(&port->mutex);
         if (drv->close)
                 drv->close(port);
-        mutex_unlock(&port->mutex);
 }
 
 static void serial_hangup(struct tty_struct *tty)
 {
         struct usb_serial_port *port = tty->driver_data;
-
         dbg("%s - port %d", __func__, port->number);
-
-        serial_down(port);
         tty_port_hangup(&port->port);
 }
 
 static void serial_close(struct tty_struct *tty, struct file *filp)
 {
         struct usb_serial_port *port = tty->driver_data;
-
         dbg("%s - port %d", __func__, port->number);
-
-        if (tty_hung_up_p(filp))
-                return;
-        if (tty_port_close_start(&port->port, tty, filp) == 0)
-                return;
-        serial_down(port);
-        tty_port_close_end(&port->port, tty);
-        tty_port_tty_set(&port->port, NULL);
+        tty_port_close(&port->port, tty, filp);
 }
 
 /**
@@ -388,10 +358,6 @@ static int serial_write(struct tty_struct *tty, const unsigned char *buf,
 
         dbg("%s - port %d, %d byte(s)", __func__, port->number, count);
 
-        /* count is managed under the mutex lock for the tty so cannot
-           drop to zero until after the last close completes */
-        WARN_ON(!port->port.count);
-
         /* pass on to the driver specific version of this function */
         retval = port->serial->type->write(tty, port, buf, count);
 
@@ -403,7 +369,6 @@ static int serial_write_room(struct tty_struct *tty)
 {
         struct usb_serial_port *port = tty->driver_data;
         dbg("%s - port %d", __func__, port->number);
-        WARN_ON(!port->port.count);
         /* pass on to the driver specific version of this function */
         return port->serial->type->write_room(tty);
 }
@@ -411,7 +376,7 @@ static int serial_write_room(struct tty_struct *tty)
 static int serial_chars_in_buffer(struct tty_struct *tty)
 {
         struct usb_serial_port *port = tty->driver_data;
-        dbg("%s = port %d", __func__, port->number);
+        dbg("%s - port %d", __func__, port->number);
 
         /* if the device was unplugged then any remaining characters
            fell out of the connector ;) */
@@ -426,7 +391,6 @@ static void serial_throttle(struct tty_struct *tty)
         struct usb_serial_port *port = tty->driver_data;
         dbg("%s - port %d", __func__, port->number);
 
-        WARN_ON(!port->port.count);
         /* pass on to the driver specific version of this function */
         if (port->serial->type->throttle)
                 port->serial->type->throttle(tty);
@@ -437,7 +401,6 @@ static void serial_unthrottle(struct tty_struct *tty)
         struct usb_serial_port *port = tty->driver_data;
         dbg("%s - port %d", __func__, port->number);
 
-        WARN_ON(!port->port.count);
         /* pass on to the driver specific version of this function */
         if (port->serial->type->unthrottle)
                 port->serial->type->unthrottle(tty);
@@ -451,8 +414,6 @@ static int serial_ioctl(struct tty_struct *tty, struct file *file,
 
         dbg("%s - port %d, cmd 0x%.4x", __func__, port->number, cmd);
 
-        WARN_ON(!port->port.count);
-
         /* pass on to the driver specific version of this function
            if it is available */
         if (port->serial->type->ioctl) {
@@ -467,7 +428,6 @@ static void serial_set_termios(struct tty_struct *tty, struct ktermios *old)
         struct usb_serial_port *port = tty->driver_data;
         dbg("%s - port %d", __func__, port->number);
 
-        WARN_ON(!port->port.count);
         /* pass on to the driver specific version of this function
            if it is available */
         if (port->serial->type->set_termios)
@@ -482,7 +442,6 @@ static int serial_break(struct tty_struct *tty, int break_state)
 
         dbg("%s - port %d", __func__, port->number);
 
-        WARN_ON(!port->port.count);
         /* pass on to the driver specific version of this function
            if it is available */
         if (port->serial->type->break_ctl)
@@ -543,7 +502,6 @@ static int serial_tiocmget(struct tty_struct *tty, struct file *file)
 
         dbg("%s - port %d", __func__, port->number);
 
-        WARN_ON(!port->port.count);
         if (port->serial->type->tiocmget)
                 return port->serial->type->tiocmget(tty, file);
         return -EINVAL;
@@ -556,7 +514,6 @@ static int serial_tiocmset(struct tty_struct *tty, struct file *file,
 
         dbg("%s - port %d", __func__, port->number);
 
-        WARN_ON(!port->port.count);
         if (port->serial->type->tiocmset)
                 return port->serial->type->tiocmset(tty, file, set, clear);
         return -EINVAL;
@@ -625,8 +582,7 @@ static void port_release(struct device *dev)
         usb_free_urb(port->write_urb);
         usb_free_urb(port->interrupt_in_urb);
         usb_free_urb(port->interrupt_out_urb);
-        if (!IS_ERR(port->write_fifo) && port->write_fifo)
-                kfifo_free(port->write_fifo);
+        kfifo_free(&port->write_fifo);
         kfree(port->bulk_in_buffer);
         kfree(port->bulk_out_buffer);
         kfree(port->interrupt_in_buffer);
@@ -725,6 +681,8 @@ static void serial_dtr_rts(struct tty_port *port, int on)
 static const struct tty_port_operations serial_port_ops = {
         .carrier_raised = serial_carrier_raised,
         .dtr_rts = serial_dtr_rts,
+        .activate = serial_activate,
+        .shutdown = serial_down,
 };
 
 int usb_serial_probe(struct usb_interface *interface,
@@ -923,7 +881,8 @@ int usb_serial_probe(struct usb_interface *interface,
                 port->port.ops = &serial_port_ops;
                 port->serial = serial;
                 spin_lock_init(&port->lock);
-                mutex_init(&port->mutex);
+                /* Keep this for private driver use for the moment but
+                   should probably go away */
                 INIT_WORK(&port->work, usb_serial_port_work);
                 serial->port[i] = port;
                 port->dev.parent = &interface->dev;
@@ -966,9 +925,7 @@ int usb_serial_probe(struct usb_interface *interface,
                         dev_err(&interface->dev, "No free urbs available\n");
                         goto probe_error;
                 }
-                port->write_fifo = kfifo_alloc(PAGE_SIZE, GFP_KERNEL,
-                        &port->lock);
-                if (IS_ERR(port->write_fifo))
+                if (kfifo_alloc(&port->write_fifo, PAGE_SIZE, GFP_KERNEL))
                         goto probe_error;
                 buffer_size = le16_to_cpu(endpoint->wMaxPacketSize);
                 port->bulk_out_size = buffer_size;