USB: ch341: refactor line-status handling

Refactor line-status handling.

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

diff --git a/drivers/usb/serial/ch341.c b/drivers/usb/serial/ch341.c
index 8908760cca9fa4eed2430f4438f16cd2d3b42273..f647dbdcb27dc94726f272fc583e705fb2454238 100644 (file)
--- a/drivers/usb/serial/ch341.c
+++ b/drivers/usb/serial/ch341.c
@@ -440,6 +440,33 @@ static int ch341_tiocmset(struct tty_struct *tty,
        return ch341_set_handshake(port->serial->dev, control);
 }
 
+static void ch341_update_line_status(struct usb_serial_port *port,
+                                       unsigned char *data, size_t len)
+{
+       struct ch341_private *priv = usb_get_serial_port_data(port);
+       unsigned long flags;
+       u8 prev_line_status = priv->line_status;
+
+       if (len < 4)
+               return;
+
+       spin_lock_irqsave(&priv->lock, flags);
+       priv->line_status = (~(data[2])) & CH341_BITS_MODEM_STAT;
+       if ((data[1] & CH341_MULT_STAT))
+               priv->multi_status_change = 1;
+       spin_unlock_irqrestore(&priv->lock, flags);
+
+       if ((priv->line_status ^ prev_line_status) & CH341_BIT_DCD) {
+               struct tty_struct *tty = tty_port_tty_get(&port->port);
+               if (tty)
+                       usb_serial_handle_dcd_change(port, tty,
+                                       priv->line_status & CH341_BIT_DCD);
+               tty_kref_put(tty);
+       }
+
+       wake_up_interruptible(&port->port.delta_msr_wait);
+}
+
 static void ch341_read_int_callback(struct urb *urb)
 {
        struct usb_serial_port *port = (struct usb_serial_port *) urb->context;
@@ -466,29 +493,7 @@ static void ch341_read_int_callback(struct urb *urb)
 
        usb_serial_debug_data(&port->dev, __func__,
                              urb->actual_length, urb->transfer_buffer);
-
-       if (actual_length >= 4) {
-               struct ch341_private *priv = usb_get_serial_port_data(port);
-               unsigned long flags;
-               u8 prev_line_status = priv->line_status;
-
-               spin_lock_irqsave(&priv->lock, flags);
-               priv->line_status = (~(data[2])) & CH341_BITS_MODEM_STAT;
-               if ((data[1] & CH341_MULT_STAT))
-                       priv->multi_status_change = 1;
-               spin_unlock_irqrestore(&priv->lock, flags);
-
-               if ((priv->line_status ^ prev_line_status) & CH341_BIT_DCD) {
-                       struct tty_struct *tty = tty_port_tty_get(&port->port);
-                       if (tty)
-                               usb_serial_handle_dcd_change(port, tty,
-                                           priv->line_status & CH341_BIT_DCD);
-                       tty_kref_put(tty);
-               }
-
-               wake_up_interruptible(&port->port.delta_msr_wait);
-       }
-
+       ch341_update_line_status(port, data, actual_length);
 exit:
        status = usb_submit_urb(urb, GFP_ATOMIC);
        if (status)