1 files changed, 11 insertions, 0 deletions

diff --git a/drivers/usb/serial/pl2303.c b/drivers/usb/serial/pl2303.c
index 45c40e6e9737..08c9181b8e48 100644
--- a/drivers/usb/serial/pl2303.c
+++ b/drivers/usb/serial/pl2303.c
@@ -678,9 +678,11 @@ static void pl2303_update_line_status(struct usb_serial_port *port,
 {
 
         struct pl2303_private *priv = usb_get_serial_port_data(port);
+        struct tty_struct *tty;
         unsigned long flags;
         u8 status_idx = UART_STATE;
         u8 length = UART_STATE + 1;
+        u8 prev_line_status;
         u16 idv, idp;
 
         idv = le16_to_cpu(port->serial->dev->descriptor.idVendor);
@@ -702,11 +704,20 @@ static void pl2303_update_line_status(struct usb_serial_port *port,
 
         /* Save off the uart status for others to look at */
         spin_lock_irqsave(&priv->lock, flags);
+        prev_line_status = priv->line_status;
         priv->line_status = data[status_idx];
         spin_unlock_irqrestore(&priv->lock, flags);
         if (priv->line_status & UART_BREAK_ERROR)
                 usb_serial_handle_break(port);
         wake_up_interruptible(&priv->delta_msr_wait);
+
+        tty = tty_port_tty_get(&port->port);
+        if (!tty)
+                return;
+        if ((priv->line_status ^ prev_line_status) & UART_DCD)
+                usb_serial_handle_dcd_change(port, tty,
+                                priv->line_status & UART_DCD);
+        tty_kref_put(tty);
 }
 
 static void pl2303_read_int_callback(struct urb *urb)