USB: keyspan_pda: clean up write-urb busy handling

Use port write_urbs_free mask rather than write_urb_busy field in struct
serial_port.

Compile-only tested.

Signed-off-by: Johan Hovold <jhovold@gmail.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>

1 files changed, 5 insertions, 5 deletions

diff --git a/drivers/usb/serial/keyspan_pda.c b/drivers/usb/serial/keyspan_pda.c
index fde553785d2b..9428cc0cfb12 100644
--- a/drivers/usb/serial/keyspan_pda.c
+++ b/drivers/usb/serial/keyspan_pda.c
@@ -479,11 +479,11 @@ static int keyspan_pda_write(struct tty_struct *tty,
            the device is full (wait until it says there is room)
         */
         spin_lock_bh(&port->lock);
-        if (port->write_urb_busy || priv->tx_throttled) {
+        if (!test_bit(0, &port->write_urbs_free) || priv->tx_throttled) {
                 spin_unlock_bh(&port->lock);
                 return 0;
         }
-        port->write_urb_busy = 1;
+        clear_bit(0, &port->write_urbs_free);
         spin_unlock_bh(&port->lock);
 
         /* At this point the URB is in our control, nobody else can submit it
@@ -565,7 +565,7 @@ static int keyspan_pda_write(struct tty_struct *tty,
         rc = count;
 exit:
         if (rc < 0)
-                port->write_urb_busy = 0;
+                set_bit(0, &port->write_urbs_free);
         return rc;
 }
 
@@ -575,7 +575,7 @@ static void keyspan_pda_write_bulk_callback(struct urb *urb)
         struct usb_serial_port *port = urb->context;
         struct keyspan_pda_private *priv;
 
-        port->write_urb_busy = 0;
+        set_bit(0, &port->write_urbs_free);
         priv = usb_get_serial_port_data(port);
 
         /* queue up a wakeup at scheduler time */
@@ -608,7 +608,7 @@ static int keyspan_pda_chars_in_buffer(struct tty_struct *tty)
            n_tty.c:normal_poll() ) that we're not writeable. */
 
         spin_lock_irqsave(&port->lock, flags);
-        if (port->write_urb_busy || priv->tx_throttled)
+        if (!test_bit(0, &port->write_urbs_free) || priv->tx_throttled)
                 ret = 256;
         spin_unlock_irqrestore(&port->lock, flags);
         return ret;