Commit c24c838e authored by Johan Hovold's avatar Johan Hovold Committed by Greg Kroah-Hartman
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USB: ssu100: switch to generic TIOCMIWAIT implementation 



Switch to the generic TIOCMIWAIT implementation.

This also fixes the issue with processes waiting for
modem-status-changes not being woken up at disconnect.

Signed-off-by: default avatarJohan Hovold <jhovold@gmail.com>
Signed-off-by: default avatarGreg Kroah-Hartman <gregkh@linuxfoundation.org>
parent 31ecdb6b

drivers/usb/serial/ssu100.c

+2 −48
Original line number Diff line number Diff line
@@ -337,49 +337,6 @@ static int get_serial_info(struct usb_serial_port *port, 
	return 0;

}



static int wait_modem_info(struct usb_serial_port *port, unsigned int arg)

{

	struct ssu100_port_private *priv = usb_get_serial_port_data(port);

	struct async_icount prev, cur;

	unsigned long flags;



	spin_lock_irqsave(&priv->status_lock, flags);

	prev = port->icount;

	spin_unlock_irqrestore(&priv->status_lock, flags);



	while (1) {

		wait_event_interruptible(port->delta_msr_wait,

					 (port->serial->disconnected ||

					  (port->icount.rng != prev.rng) ||

					  (port->icount.dsr != prev.dsr) ||

					  (port->icount.dcd != prev.dcd) ||

					  (port->icount.cts != prev.cts)));



		if (signal_pending(current))

			return -ERESTARTSYS;



		if (port->serial->disconnected)

			return -EIO;



		spin_lock_irqsave(&priv->status_lock, flags);

		cur = port->icount;

		spin_unlock_irqrestore(&priv->status_lock, flags);



		if ((prev.rng == cur.rng) &&

		    (prev.dsr == cur.dsr) &&

		    (prev.dcd == cur.dcd) &&

		    (prev.cts == cur.cts))

			return -EIO;



		if ((arg & TIOCM_RNG && (prev.rng != cur.rng)) ||

		    (arg & TIOCM_DSR && (prev.dsr != cur.dsr)) ||

		    (arg & TIOCM_CD  && (prev.dcd != cur.dcd)) ||

		    (arg & TIOCM_CTS && (prev.cts != cur.cts)))

			return 0;

	}

	return 0;

}



static int ssu100_ioctl(struct tty_struct *tty,

		    unsigned int cmd, unsigned long arg)

{
@@ -391,10 +348,6 @@ static int ssu100_ioctl(struct tty_struct *tty, 
	case TIOCGSERIAL:

		return get_serial_info(port,

				       (struct serial_struct __user *) arg);



	case TIOCMIWAIT:

		return wait_modem_info(port, arg);



	default:

		break;

	}
@@ -509,7 +462,7 @@ static void ssu100_update_msr(struct usb_serial_port *port, u8 msr) 
			port->icount.dcd++;

		if (msr & UART_MSR_TERI)

			port->icount.rng++;

		wake_up_interruptible(&port->delta_msr_wait);

		wake_up_interruptible(&port->port.delta_msr_wait);

	}

}
@@ -607,6 +560,7 @@ static struct usb_serial_driver ssu100_device = { 
	.process_read_urb    = ssu100_process_read_urb,

	.tiocmget            = ssu100_tiocmget,

	.tiocmset            = ssu100_tiocmset,

	.tiocmiwait          = usb_serial_generic_tiocmiwait,

	.get_icount	     = usb_serial_generic_get_icount,

	.ioctl               = ssu100_ioctl,

	.set_termios         = ssu100_set_termios,

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