USB: cypress_m8: fix potential scheduling while atomic

Remove erroneous call to usb_clear_halt which is blocking and cannot be
used in interrupt context.

This code has possibly never been executed as it would cause an oops if
it was. Simply treat a stalled-endpoint error as any other error
condition.
Signed-off-by: Johan Hovold <jhovold@gmail.com>
Signed-off-by: Greg Kroah-Hartman <greg@kroah.com>

drivers/usb/serial/cypress_m8.c

@@ -1224,7 +1224,6 @@ static void cypress_write_int_callback(struct urb *urb)
 	struct usb_serial_port *port = urb->context;
 	struct cypress_private *priv = usb_get_serial_port_data(port);
 	struct device *dev = &urb->dev->dev;
-	int result;
 	int status = urb->status;
 
 	switch (status) {
@@ -1239,21 +1238,9 @@ static void cypress_write_int_callback(struct urb *urb)
 			__func__, status);
 		priv->write_urb_in_use = 0;
 		return;
-	case -EPIPE: /* no break needed; clear halt and resubmit */
-		if (!priv->comm_is_ok)
-			break;
-		usb_clear_halt(port->serial->dev, 0x02);
-		/* error in the urb, so we have to resubmit it */
-		dev_dbg(dev, "%s - nonzero write bulk status received: %d\n",
-			__func__, status);
-		port->interrupt_out_urb->transfer_buffer_length = 1;
-		result = usb_submit_urb(port->interrupt_out_urb, GFP_ATOMIC);
-		if (!result)
-			return;
-		dev_err(dev, "%s - failed resubmitting write urb, error %d\n",
-			__func__, result);
-		cypress_set_dead(port);
-		break;
+	case -EPIPE:
+		/* Cannot call usb_clear_halt while in_interrupt */
+		/* FALLTHROUGH */
 	default:
 		dev_err(dev, "%s - unexpected nonzero write status received: %d\n",
 			__func__, status);