USB: ch341: fix TIOCMIWAIT and disconnect

Use tty-port modem-status-change wait queue on which processes are woken
up at hangup and disconnect.

Currently a process waiting on modem-status changes will not be woken on
device disconnect as wake up was only done in dtr_rts which isn't
guaranteed to be called (e.g. if HUPCL is not set).

Also remove the redundant wake-up call from dtr_rts.

Signed-off-by: Johan Hovold <jhovold@gmail.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
This commit is contained in:
Johan Hovold 2013-03-21 12:37:01 +01:00 committed by Greg Kroah-Hartman
parent 7bb98f0edd
commit 3f55043192

View File

@ -296,7 +296,6 @@ static void ch341_dtr_rts(struct usb_serial_port *port, int on)
priv->line_control &= ~(CH341_BIT_RTS | CH341_BIT_DTR);
spin_unlock_irqrestore(&priv->lock, flags);
ch341_set_handshake(port->serial->dev, priv->line_control);
wake_up_interruptible(&port->delta_msr_wait);
}
static void ch341_close(struct usb_serial_port *port)
@ -489,7 +488,7 @@ static void ch341_read_int_callback(struct urb *urb)
tty_kref_put(tty);
}
wake_up_interruptible(&port->delta_msr_wait);
wake_up_interruptible(&port->port.delta_msr_wait);
}
exit:
@ -516,7 +515,7 @@ static int ch341_tiocmiwait(struct tty_struct *tty, unsigned long arg)
spin_unlock_irqrestore(&priv->lock, flags);
while (!multi_change) {
interruptible_sleep_on(&port->delta_msr_wait);
interruptible_sleep_on(&port->port.delta_msr_wait);
/* see if a signal did it */
if (signal_pending(current))
return -ERESTARTSYS;