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, 31 insertions, 48 deletions

diff --git a/drivers/usb/serial/pl2303.c b/drivers/usb/serial/pl2303.c
index 751a533a4347..e02dc3d643c7 100644
--- a/drivers/usb/serial/pl2303.c
+++ b/drivers/usb/serial/pl2303.c
@@ -652,69 +652,41 @@ static void pl2303_set_termios(struct tty_struct *tty,
         kfree(buf);
 }
 
-static void pl2303_close(struct tty_struct *tty,
-                        struct usb_serial_port *port, struct file *filp)
+static void pl2303_dtr_rts(struct usb_serial_port *port, int on)
+{
+        struct pl2303_private *priv = usb_get_serial_port_data(port);
+        unsigned long flags;
+        u8 control;
+
+        spin_lock_irqsave(&priv->lock, flags);
+        /* Change DTR and RTS */
+        if (on)
+                priv->line_control |= (CONTROL_DTR | CONTROL_RTS);
+        else
+                priv->line_control &= ~(CONTROL_DTR | CONTROL_RTS);
+        control = priv->line_control;
+        spin_unlock_irqrestore(&priv->lock, flags);
+        set_control_lines(port->serial->dev, control);
+}
+
+static void pl2303_close(struct usb_serial_port *port)
 {
         struct pl2303_private *priv = usb_get_serial_port_data(port);
         unsigned long flags;
-        unsigned int c_cflag;
-        int bps;
-        long timeout;
-        wait_queue_t wait;
 
         dbg("%s - port %d", __func__, port->number);
 
-        /* wait for data to drain from the buffer */
         spin_lock_irqsave(&priv->lock, flags);
-        timeout = PL2303_CLOSING_WAIT;
-        init_waitqueue_entry(&wait, current);
-        add_wait_queue(&tty->write_wait, &wait);
-        for (;;) {
-                set_current_state(TASK_INTERRUPTIBLE);
-                if (pl2303_buf_data_avail(priv->buf) == 0 ||
-                    timeout == 0 || signal_pending(current) ||
-                    port->serial->disconnected)
-                        break;
-                spin_unlock_irqrestore(&priv->lock, flags);
-                timeout = schedule_timeout(timeout);
-                spin_lock_irqsave(&priv->lock, flags);
-        }
-        set_current_state(TASK_RUNNING);
-        remove_wait_queue(&tty->write_wait, &wait);
         /* clear out any remaining data in the buffer */
         pl2303_buf_clear(priv->buf);
         spin_unlock_irqrestore(&priv->lock, flags);
 
-        /* wait for characters to drain from the device */
-        /* (this is long enough for the entire 256 byte */
-        /* pl2303 hardware buffer to drain with no flow */
-        /* control for data rates of 1200 bps or more, */
-        /* for lower rates we should really know how much */
-        /* data is in the buffer to compute a delay */
-        /* that is not unnecessarily long) */
-        bps = tty_get_baud_rate(tty);
-        if (bps > 1200)
-                timeout = max((HZ*2560)/bps, HZ/10);
-        else
-                timeout = 2*HZ;
-        schedule_timeout_interruptible(timeout);
-
         /* shutdown our urbs */
         dbg("%s - shutting down urbs", __func__);
         usb_kill_urb(port->write_urb);
         usb_kill_urb(port->read_urb);
         usb_kill_urb(port->interrupt_in_urb);
 
-        if (tty) {
-                c_cflag = tty->termios->c_cflag;
-                if (c_cflag & HUPCL) {
-                        /* drop DTR and RTS */
-                        spin_lock_irqsave(&priv->lock, flags);
-                        priv->line_control = 0;
-                        spin_unlock_irqrestore(&priv->lock, flags);
-                        set_control_lines(port->serial->dev, 0);
-                }
-        }
 }
 
 static int pl2303_open(struct tty_struct *tty,
@@ -748,7 +720,7 @@ static int pl2303_open(struct tty_struct *tty,
         if (result) {
                 dev_err(&port->dev, "%s - failed submitting read urb,"
                         " error %d\n", __func__, result);
-                pl2303_close(tty, port, NULL);
+                pl2303_close(port);
                 return -EPROTO;
         }
 
@@ -758,9 +730,10 @@ static int pl2303_open(struct tty_struct *tty,
         if (result) {
                 dev_err(&port->dev, "%s - failed submitting interrupt urb,"
                         " error %d\n", __func__, result);
-                pl2303_close(tty, port, NULL);
+                pl2303_close(port);
                 return -EPROTO;
         }
+        port->port.drain_delay = 256;
         return 0;
 }
 
@@ -821,6 +794,14 @@ static int pl2303_tiocmget(struct tty_struct *tty, struct file *file)
         return result;
 }
 
+static int pl2303_carrier_raised(struct usb_serial_port *port)
+{
+        struct pl2303_private *priv = usb_get_serial_port_data(port);
+        if (priv->line_status & UART_DCD)
+                return 1;
+        return 0;
+}
+
 static int wait_modem_info(struct usb_serial_port *port, unsigned int arg)
 {
         struct pl2303_private *priv = usb_get_serial_port_data(port);
@@ -1125,6 +1106,8 @@ static struct usb_serial_driver pl2303_device = {
         .num_ports =            1,
         .open =                 pl2303_open,
         .close =                pl2303_close,
+        .dtr_rts =              pl2303_dtr_rts,
+        .carrier_raised =       pl2303_carrier_raised,
         .write =                pl2303_write,
         .ioctl =                pl2303_ioctl,
         .break_ctl =            pl2303_break_ctl,