USB: ch341: clean up line-status handling

Clean up line-status handling.

Signed-off-by: Johan Hovold <jhovold@gmail.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
This commit is contained in:
Johan Hovold 2014-01-02 22:49:29 +01:00 committed by Greg Kroah-Hartman
parent ac035628a9
commit b770081f88
1 changed files with 14 additions and 8 deletions

View File

@ -444,25 +444,31 @@ 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);
struct tty_struct *tty;
unsigned long flags;
u8 prev_line_status = priv->line_status;
u8 status;
u8 delta;
if (len < 4)
return;
status = ~data[2] & CH341_BITS_MODEM_STAT;
spin_lock_irqsave(&priv->lock, flags);
priv->line_status = (~(data[2])) & CH341_BITS_MODEM_STAT;
if ((data[1] & CH341_MULT_STAT))
delta = status ^ priv->line_status;
priv->line_status = status;
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)
if (delta & CH341_BIT_DCD) {
tty = tty_port_tty_get(&port->port);
if (tty) {
usb_serial_handle_dcd_change(port, tty,
priv->line_status & CH341_BIT_DCD);
status & CH341_BIT_DCD);
tty_kref_put(tty);
}
}
wake_up_interruptible(&port->port.delta_msr_wait);
}