USB: removal of tty->low_latency hack dating back to the old serial code

This removes tty->low_latency from all USB serial drivers that push
data into the tty layer at hard interrupt context. It's no longer needed
and actually harmful.

Signed-off-by: Oliver Neukum <oliver@neukum.org>
Cc: Alan Cox <alan@lxorguk.ukuu.org.uk>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>

1 files changed, 0 insertions, 8 deletions

diff --git a/drivers/usb/serial/visor.c b/drivers/usb/serial/visor.c
index 4facce3d9364..5ac414bda718 100644
--- a/drivers/usb/serial/visor.c
+++ b/drivers/usb/serial/visor.c
@@ -296,14 +296,6 @@ static int visor_open(struct tty_struct *tty, struct usb_serial_port *port,
         priv->throttled = 0;
         spin_unlock_irqrestore(&priv->lock, flags);
 
-        /*
-         * Force low_latency on so that our tty_push actually forces the data
-         * through, otherwise it is scheduled, and with high data rates (like
-         * with OHCI) data can get lost.
-         */
-        if (tty)
-                tty->low_latency = 1;
-
         /* Start reading from the device */
         usb_fill_bulk_urb(port->read_urb, serial->dev,
                            usb_rcvbulkpipe(serial->dev,