diff options
Diffstat (limited to 'drivers/usb/serial/pl2303.c')
| -rw-r--r-- | drivers/usb/serial/pl2303.c | 26 |
1 files changed, 15 insertions, 11 deletions
diff --git a/drivers/usb/serial/pl2303.c b/drivers/usb/serial/pl2303.c index 9951dfddc784..11de1f169308 100644 --- a/drivers/usb/serial/pl2303.c +++ b/drivers/usb/serial/pl2303.c @@ -808,7 +808,8 @@ static void pl2303_update_line_status(struct usb_serial_port *port, struct tty_struct *tty; unsigned long flags; unsigned int status_idx = UART_STATE_INDEX; - u8 prev_line_status; + u8 status; + u8 delta; if (spriv->quirks & PL2303_QUIRK_UART_STATE_IDX0) status_idx = 0; @@ -816,24 +817,27 @@ static void pl2303_update_line_status(struct usb_serial_port *port, if (actual_length < status_idx + 1) return; + status = data[status_idx]; + /* 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]; + delta = priv->line_status ^ status; + priv->line_status = status; spin_unlock_irqrestore(&priv->lock, flags); - if (priv->line_status & UART_BREAK_ERROR) + if (status & UART_BREAK_ERROR) usb_serial_handle_break(port); wake_up_interruptible(&port->port.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); + if (delta & UART_DCD) { + tty = tty_port_tty_get(&port->port); + if (tty) { + usb_serial_handle_dcd_change(port, tty, + status & UART_DCD); + tty_kref_put(tty); + } + } } static void pl2303_read_int_callback(struct urb *urb) |