tty: Bring the usb tty port structure into more use

This allows us to clean stuff up, but is probably also going to cause
some app breakage with buggy apps as we now implement proper POSIX behaviour
for USB ports matching all the other ports. This does also mean other apps
that break on USB will now work properly.

Signed-off-by: Alan Cox <alan@lxorguk.ukuu.org.uk>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

1 files changed, 19 insertions, 18 deletions

diff --git a/drivers/usb/serial/mct_u232.c b/drivers/usb/serial/mct_u232.c
index 82930a7d5093..873795548fc0 100644
--- a/drivers/usb/serial/mct_u232.c
+++ b/drivers/usb/serial/mct_u232.c
@@ -95,8 +95,8 @@ static int  mct_u232_startup(struct usb_serial *serial);
 static void mct_u232_shutdown(struct usb_serial *serial);
 static int  mct_u232_open(struct tty_struct *tty,
                         struct usb_serial_port *port, struct file *filp);
-static void mct_u232_close(struct tty_struct *tty,
-                        struct usb_serial_port *port, struct file *filp);
+static void mct_u232_close(struct usb_serial_port *port);
+static void mct_u232_dtr_rts(struct usb_serial_port *port, int on);
 static void mct_u232_read_int_callback(struct urb *urb);
 static void mct_u232_set_termios(struct tty_struct *tty,
                         struct usb_serial_port *port, struct ktermios *old);
@@ -140,6 +140,7 @@ static struct usb_serial_driver mct_u232_device = {
         .num_ports =         1,
         .open =              mct_u232_open,
         .close =             mct_u232_close,
+        .dtr_rts =           mct_u232_dtr_rts,
         .throttle =          mct_u232_throttle,
         .unthrottle =        mct_u232_unthrottle,
         .read_int_callback = mct_u232_read_int_callback,
@@ -496,29 +497,29 @@ error:
         return retval;
 } /* mct_u232_open */
 
-
-static void mct_u232_close(struct tty_struct *tty,
-                        struct usb_serial_port *port, struct file *filp)
+static void mct_u232_dtr_rts(struct usb_serial_port *port, int on)
 {
-        unsigned int c_cflag;
         unsigned int control_state;
         struct mct_u232_private *priv = usb_get_serial_port_data(port);
-        dbg("%s port %d", __func__, port->number);
 
-        if (tty) {
-                c_cflag = tty->termios->c_cflag;
-                mutex_lock(&port->serial->disc_mutex);
-                if (c_cflag & HUPCL && !port->serial->disconnected) {
-                        /* drop DTR and RTS */
-                        spin_lock_irq(&priv->lock);
+        mutex_lock(&port->serial->disc_mutex);
+        if (!port->serial->disconnected) {
+                /* drop DTR and RTS */
+                spin_lock_irq(&priv->lock);
+                if (on)
+                        priv->control_state |= TIOCM_DTR | TIOCM_RTS;
+                else
                         priv->control_state &= ~(TIOCM_DTR | TIOCM_RTS);
-                        control_state = priv->control_state;
-                        spin_unlock_irq(&priv->lock);
-                        mct_u232_set_modem_ctrl(port->serial, control_state);
-                }
-                mutex_unlock(&port->serial->disc_mutex);
+                control_state = priv->control_state;
+                spin_unlock_irq(&priv->lock);
+                mct_u232_set_modem_ctrl(port->serial, control_state);
         }
+        mutex_unlock(&port->serial->disc_mutex);
+}
 
+static void mct_u232_close(struct usb_serial_port *port)
+{
+        dbg("%s port %d", __func__, port->number);
 
         if (port->serial->dev) {
                 /* shutdown our urbs */