path: root/drivers/usb/gadget/function/u_serial.c

// SPDX-License-Identifier: GPL-2.0+
/*
 * u_serial.c - utilities for USB gadget "serial port"/TTY support
 *
 * Copyright (C) 2003 Al Borchers (alborchers@steinerpoint.com)
 * Copyright (C) 2008 David Brownell
 * Copyright (C) 2008 by Nokia Corporation
 *
 * This code also borrows from usbserial.c, which is
 * Copyright (C) 1999 - 2002 Greg Kroah-Hartman (greg@kroah.com)
 * Copyright (C) 2000 Peter Berger (pberger@brimson.com)
 * Copyright (C) 2000 Al Borchers (alborchers@steinerpoint.com)
 */

/* #define VERBOSE_DEBUG */

#include <linux/kernel.h>
#include <linux/sched.h>
#include <linux/device.h>
#include <linux/delay.h>
#include <linux/tty.h>
#include <linux/tty_flip.h>
#include <linux/slab.h>
#include <linux/export.h>
#include <linux/module.h>
#include <linux/console.h>
#include <linux/kstrtox.h>
#include <linux/kthread.h>
#include <linux/workqueue.h>
#include <linux/kfifo.h>

#include "u_serial.h"


/*
 * This component encapsulates the TTY layer glue needed to provide basic
 * "serial port" functionality through the USB gadget stack.  Each such
 * port is exposed through a /dev/ttyGS