USB: mos7840: 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: Johan Hovold <jhovold@gmail.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

1 files changed, 2 insertions, 46 deletions

diff --git a/drivers/usb/serial/mos7840.c b/drivers/usb/serial/mos7840.c
index 92feae6e8851..f0b4e5c01e13 100644
--- a/drivers/usb/serial/mos7840.c
+++ b/drivers/usb/serial/mos7840.c
@@ -219,7 +219,6 @@ struct moschip_port {
         char open;
         char open_ports;
         wait_queue_head_t wait_chase;   /* for handling sleeping while waiting for chase to finish */
-        int delta_msr_cond;
         struct usb_serial_port *port;   /* loop back to the owner of this object */
 
         /* Offsets */
@@ -413,8 +412,7 @@ static void mos7840_handle_new_msr(struct moschip_port *port, __u8 new_msr)
                 if (new_msr & MOS_MSR_DELTA_RI)
                         icount->rng++;
 
-                mos7840_port->delta_msr_cond = 1;
-                wake_up_interruptible(&port->port->delta_msr_wait);
+                wake_up_interruptible(&port->port->port.delta_msr_wait);
         }
 }
 
@@ -2113,9 +2111,6 @@ static int mos7840_ioctl(struct tty_struct *tty,
         struct usb_serial_port *port = tty->driver_data;
         void __user *argp = (void __user *)arg;
         struct moschip_port *mos7840_port;
-        unsigned long flags;
-        struct async_icount cnow;
-        struct async_icount cprev;
 
         if (mos7840_port_paranoia_check(port, __func__))
                 return -1;
@@ -2141,46 +2136,6 @@ static int mos7840_ioctl(struct tty_struct *tty,
         case TIOCSSERIAL:
                 dev_dbg(&port->dev, "%s TIOCSSERIAL\n", __func__);
                 break;
-
-        case TIOCMIWAIT:
-                dev_dbg(&port->dev, "%s  TIOCMIWAIT\n", __func__);
-                spin_lock_irqsave(&port->lock, flags);
-                cprev = port->icount;
-                spin_unlock_irqrestore(&port->lock, flags);
-                while (1) {
-                        /* interruptible_sleep_on(&mos7840_port->delta_msr_wait); */
-                        mos7840_port->delta_msr_cond = 0;
-                        wait_event_interruptible(port->delta_msr_wait,
-                                                 (port->serial->disconnected ||
-                                                  mos7840_port->
-                                                  delta_msr_cond == 1));
-
-                        /* see if a signal did it */
-                        if (signal_pending(current))
-                                return -ERESTARTSYS;
-
-                        if (port->serial->disconnected)
-                                return -EIO;
-
-                        spin_lock_irqsave(&port->lock, flags);
-                        cnow = port->icount;
-                        spin_unlock_irqrestore(&port->lock, flags);
-
-                        if (cnow.rng == cprev.rng && cnow.dsr == cprev.dsr &&
-                            cnow.dcd == cprev.dcd && cnow.cts == cprev.cts)
-                                return -EIO;    /* no change => error */
-
-                        if (((arg & TIOCM_RNG) && (cnow.rng != cprev.rng)) ||
-                            ((arg & TIOCM_DSR) && (cnow.dsr != cprev.dsr)) ||
-                            ((arg & TIOCM_CD) && (cnow.dcd != cprev.dcd)) ||
-                            ((arg & TIOCM_CTS) && (cnow.cts != cprev.cts))) {
-                                return 0;
-                        }
-                        cprev = cnow;
-                }
-                /* NOTREACHED */
-                break;
-
         default:
                 break;
         }
@@ -2527,6 +2482,7 @@ static struct usb_serial_driver moschip7840_4port_device = {
         .break_ctl = mos7840_break,
         .tiocmget = mos7840_tiocmget,
         .tiocmset = mos7840_tiocmset,
+        .tiocmiwait = usb_serial_generic_tiocmiwait,
         .get_icount = usb_serial_generic_get_icount,
         .port_probe = mos7840_port_probe,
         .port_remove = mos7840_port_remove,