tty: Fix various bogus WARN checks in the usb serial layer

[safe/jmp/linux-2.6] / drivers / usb / serial / usb-serial.c

diff --git a/drivers/usb/serial/usb-serial.c b/drivers/usb/serial/usb-serial.c
index b0649d9..3873660 100644 (file)
--- a/drivers/usb/serial/usb-serial.c
+++ b/drivers/usb/serial/usb-serial.c
@@ -254,15 +254,12 @@ static int serial_activate(struct tty_port *tport, struct tty_struct *tty)
        struct usb_serial *serial = port->serial;
        int retval;
 
-       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;
 }
 
@@ -276,57 +273,40 @@ static int serial_open(struct tty_struct *tty, struct file *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);
 }
 
 /**
@@ -378,10 +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);
 
@@ -393,7 +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);
 }
@@ -401,7 +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 ;) */
@@ -416,7 +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);
@@ -427,7 +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);
@@ -441,8 +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) {
@@ -457,7 +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)
@@ -472,7 +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)
@@ -533,7 +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;
@@ -546,7 +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;
@@ -615,8 +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);
@@ -716,6 +682,7 @@ 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,
@@ -914,7 +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;
@@ -957,9 +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;