Linux中终端设备驱动

核心层

1、在tty_io.c文件（drivers/char/ ）

 

static const struct file_operations tty_fops = {
	.llseek		= no_llseek,
	.read		= tty_read,
	.write		= tty_write,
	.poll		= tty_poll,
	.unlocked_ioctl	= tty_ioctl,
	.compat_ioctl	= tty_compat_ioctl,
	.open		= tty_open,
	.release	= tty_release,
	.fasync		= tty_fasync,
};

static ssize_t tty_write(struct file *file, const char __user *buf,
						size_t count, loff_t *ppos)
{
	struct tty_struct *tty;
	struct inode *inode = file->f_path.dentry->d_inode;
	ssize_t ret;
	struct tty_ldisc *ld;

	tty = (struct tty_struct *)file->private_data;
	if (tty_paranoia_check(tty, inode, "tty_write"))
		return -EIO;
	if (!tty || !tty->ops->write ||
		(test_bit(TTY_IO_ERROR, &tty->flags)))
			return -EIO;
	/* Short term debug to catch buggy drivers */
	if (tty->ops->write_room == NULL)
		printk(KERN_ERR "tty driver %s lacks a write_room method.\n",
			tty->driver->name);
	ld = tty_ldisc_ref_wait(tty);
	if (!ld->ops->write)
		ret = -EIO;
	else
		ret = do_tty_write(ld->ops->write, tty, file, buf, count);
	tty_ldisc_deref(ld);
	return ret;
}

 

在tty_write（）函数中，调用了线路规程：

其中在 tty_struct 结构中，有成员  tty_ldsic：

struct tty_struct {
	int	magic;
	struct kref kref;
	struct tty_driver *driver;
	const struct tty_operations *ops;
	int index;
	/* The ldisc objects are protected by tty_ldisc_lock at the moment */
	struct tty_ldisc ldisc;
	struct mutex termios_mutex;
	spinlock_t ctrl_lock;
	/* Termios values are protected by the termios mutex */
	struct ktermios *termios, *termios_locked;
	struct termiox *termiox;	/* May be NULL for unsupported */
	char name[64];
	struct pid *pgrp;		/* Protected by ctrl lock */
	struct pid *session;
	unsigned long flags;
	int count;
	struct winsize winsize;		/* termios mutex */
	unsigned char stopped:1, hw_stopped:1, flow_stopped:1, packet:1;
	unsigned char low_latency:1, warned:1;
	unsigned char ctrl_status;	/* ctrl_lock */
	unsigned int receive_room;	/* Bytes free for queue */

	struct tty_struct *link;
	struct fasync_struct *fasync;
	struct tty_bufhead buf;		/* Locked internally */
	int alt_speed;		/* For magic substitution of 38400 bps */
	wait_queue_head_t write_wait;
	wait_queue_head_t read_wait;
	struct work_struct hangup_work;
	void *disc_data;
	void *driver_data;
	struct list_head tty_files;

#define N_TTY_BUF_SIZE 4096

	/*
	 * The following is data for the N_TTY line discipline.  For
	 * historical reasons, this is included in the tty structure.
	 * Mostly locked by the BKL.
	 */
	unsigned int column;
	unsigned char lnext:1, erasing:1, raw:1, real_raw:1, icanon:1;
	unsigned char closing:1;
	unsigned char echo_overrun:1;
	unsigned short minimum_to_wake;
	unsigned long overrun_time;
	int num_overrun;
	unsigned long process_char_map[256/(8*sizeof(unsigned long))];
	char *read_buf;
	int read_head;
	int read_tail;
	int read_cnt;
	unsigned long read_flags[N_TTY_BUF_SIZE/(8*sizeof(unsigned long))];
	unsigned char *echo_buf;
	unsigned int echo_pos;
	unsigned int echo_cnt;
	int canon_data;
	unsigned long canon_head;
	unsigned int canon_column;
	struct mutex atomic_read_lock;
	struct mutex atomic_write_lock;
	struct mutex output_lock;
	struct mutex echo_lock;
	unsigned char *write_buf;
	int write_cnt;
	spinlock_t read_lock;
	/* If the tty has a pending do_SAK, queue it here - akpm */
	struct work_struct SAK_work;
	struct tty_port *port;
};

 

在源码中，搜索 “tty_ldisc_ops” ，就可以，找到所有的 线路规程； 典型的 /drviers/char/n_tty.c文件针对 N_TTY线路规程实现了 tty_disc结构体中的成员。

struct tty_ldisc_ops tty_ldisc_N_TTY = {
	.magic           = TTY_LDISC_MAGIC,
	.name            = "n_tty",
	.open            = n_tty_open,
	.close           = n_tty_close,
	.flush_buffer    = n_tty_flush_buffer,
	.chars_in_buffer = n_tty_chars_in_buffer,
	.read            = n_tty_read,
	.write           = n_tty_write,
	.ioctl           = n_tty_ioctl,
	.set_termios     = n_tty_set_termios,
	.poll            = n_tty_poll,
	.receive_buf     = n_tty_receive_buf,
	.write_wakeup    = n_tty_write_wakeup
};

其中的 write 方法实现如下：

static ssize_t n_tty_write(struct tty_struct *tty, struct file *file,
			   const unsigned char *buf, size_t nr)
{
	const unsigned char *b = buf;
	DECLARE_WAITQUEUE(wait, current);
	int c;
	ssize_t retval = 0;

	/* Job control check -- must be done at start (POSIX.1 7.1.1.4). */
	if (L_TOSTOP(tty) && file->f_op->write != redirected_tty_write) {
		retval = tty_check_change(tty);
		if (retval)
			return retval;
	}

	/* Write out any echoed characters that are still pending */
	process_echoes(tty);

	add_wait_queue(&tty->write_wait, &wait);
	while (1) {
		set_current_state(TASK_INTERRUPTIBLE);
		if (signal_pending(current)) {
			retval = -ERESTARTSYS;
			break;
		}
		if (tty_hung_up_p(file) || (tty->link && !tty->link->count)) {
			retval = -EIO;
			break;
		}
		if (O_OPOST(tty) && !(test_bit(TTY_HW_COOK_OUT, &tty->flags))) {
			while (nr > 0) {
				ssize_t num = process_output_block(tty, b, nr);
				if (num < 0) {
					if (num == -EAGAIN)
						break;
					retval = num;
					goto break_out;
				}
				b += num;
				nr -= num;
				if (nr == 0)
					break;
				c = *b;
				if (process_output(c, tty) < 0)
					break;
				b++; nr--;
			}
			if (tty->ops->flush_chars)
				tty->ops->flush_chars(tty);  //刷新缓冲区并丢弃任何剩下的数据。
		} else {
			while (nr > 0) {
				c = tty->ops->write(tty, b, nr); //跳转到tty 驱动着一层。
				if (c < 0) {
					retval = c;
					goto break_out;
				}
				if (!c)
					break;
				b += c;
				nr -= c;
			}
		}
		if (!nr)
			break;
		if (file->f_flags & O_NONBLOCK) {
			retval = -EAGAIN;
			break;
		}
		schedule();
	}
break_out:
	__set_current_state(TASK_RUNNING);
	remove_wait_queue(&tty->write_wait, &wait);
	if (b - buf != nr && tty->fasync)
		set_bit(TTY_DO_WRITE_WAKEUP, &tty->flags);
	return (b - buf) ? b - buf : retval;
}

通过上面的调用流程后，就通过指针，线路规程这一层，调用了tty驱动着一层。

 

尽管一个特定的UAR设备驱动完全可以按照 前面的方法就行设计， 即 定义tty_driver并实现 tty_operation 其中的成员函数，但是linux已经在一个文件   serial_core.c 中实现了 UART 设备的通用 tyy驱动层（姑且称为串口驱动层）。这样子，UART驱动的主要任务就 演变成  实现 serial-core.c中定义的一组 uart_xxx皆苦并非 tty_xxx接口。

1、在serial_core.h中 ，定义了 uart_driver结构

struct uart_driver {
	struct module		*owner;
	const char		*driver_name;
	const char		*dev_name;
	int			 major;
	int			 minor;
	int			 nr;
	struct console		*cons;

	/*
	 * these are private; the low level driver should not
	 * touch these; they should be initialised to NULL
	 */
	struct uart_state	*state;
	struct tty_driver	*tty_driver;
};

而注册函数演变成 uart_register_driver( ). ,在注册uart driver 的函数 ，实际上也调用了 tty_register_driver （);

int uart_register_driver(struct uart_driver *drv)
{
	struct tty_driver *normal = NULL;
	int i, retval;

	BUG_ON(drv->state);

	/*
	 * Maybe we should be using a slab cache for this, especially if
	 * we have a large number of ports to handle.
	 */
	drv->state = kzalloc(sizeof(struct uart_state) * drv->nr, GFP_KERNEL);
	retval = -ENOMEM;
	if (!drv->state)
		goto out;

	normal  = alloc_tty_driver(drv->nr);
	if (!normal)
		goto out;

	drv->tty_driver = normal;

	normal->owner		= drv->owner;
	normal->driver_name	= drv->driver_name;
	normal->name		= drv->dev_name;
	normal->major		= drv->major;
	normal->minor_start	= drv->minor;
	normal->type		= TTY_DRIVER_TYPE_SERIAL;
	normal->subtype		= SERIAL_TYPE_NORMAL;
	normal->init_termios	= tty_std_termios;
	normal->init_termios.c_cflag = B9600 | CS8 | CREAD | HUPCL | CLOCAL;
	normal->init_termios.c_ispeed = normal->init_termios.c_ospeed = 9600;
	normal->flags		= TTY_DRIVER_REAL_RAW | TTY_DRIVER_DYNAMIC_DEV;
	normal->driver_state    = drv;
	tty_set_operations(normal, &uart_ops);

	/*
	 * Initialise the UART state(s).
	 */
	for (i = 0; i < drv->nr; i++) {
		struct uart_state *state = drv->state + i;

		state->close_delay     = 500;	/* .5 seconds */
		state->closing_wait    = 30000;	/* 30 seconds */
		mutex_init(&state->mutex);

		tty_port_init(&state->info.port);       
		init_waitqueue_head(&state->info.delta_msr_wait);
		tasklet_init(&state->info.tlet, uart_tasklet_action,
			     (unsigned long)state);
	}

	retval = tty_register_driver(normal);
 out:
	if (retval < 0) {
		put_tty_driver(normal);
		kfree(drv->state);
	}
	return retval;
}

uart_port 结构如下 ：

struct uart_port {
	spinlock_t		lock;			/* port lock */
	unsigned long		iobase;			/* in/out[bwl] */
	unsigned char __iomem	*membase;		/* read/write[bwl] */
	unsigned int		(*serial_in)(struct uart_port *, int);
	void			(*serial_out)(struct uart_port *, int, int);
	unsigned int		irq;			/* irq number */
	unsigned int		uartclk;		/* base uart clock */
	unsigned int		fifosize;		/* tx fifo size */
	unsigned char		x_char;			/* xon/xoff char */
	unsigned char		regshift;		/* reg offset shift */
	unsigned char		iotype;			/* io access style */
	unsigned char		unused1;

#define UPIO_PORT		(0)
#define UPIO_HUB6		(1)
#define UPIO_MEM		(2)
#define UPIO_MEM32		(3)
#define UPIO_AU			(4)			/* Au1x00 type IO */
#define UPIO_TSI		(5)			/* Tsi108/109 type IO */
#define UPIO_DWAPB		(6)			/* DesignWare APB UART */
#define UPIO_RM9000		(7)			/* RM9000 type IO */

	unsigned int		read_status_mask;	/* driver specific */
	unsigned int		ignore_status_mask;	/* driver specific */
	struct uart_info	*info;			/* pointer to parent info */
	struct uart_icount	icount;			/* statistics */

	struct console		*cons;			/* struct console, if any */
#ifdef CONFIG_SERIAL_CORE_CONSOLE
	unsigned long		sysrq;			/* sysrq timeout */
#endif

	upf_t			flags;

#define UPF_FOURPORT		((__force upf_t) (1 << 1))
#define UPF_SAK			((__force upf_t) (1 << 2))
#define UPF_SPD_MASK		((__force upf_t) (0x1030))
#define UPF_SPD_HI		((__force upf_t) (0x0010))
#define UPF_SPD_VHI		((__force upf_t) (0x0020))
#define UPF_SPD_CUST		((__force upf_t) (0x0030))
#define UPF_SPD_SHI		((__force upf_t) (0x1000))
#define UPF_SPD_WARP		((__force upf_t) (0x1010))
#define UPF_SKIP_TEST		((__force upf_t) (1 << 6))
#define UPF_AUTO_IRQ		((__force upf_t) (1 << 7))
#define UPF_HARDPPS_CD		((__force upf_t) (1 << 11))
#define UPF_LOW_LATENCY		((__force upf_t) (1 << 13))
#define UPF_BUGGY_UART		((__force upf_t) (1 << 14))
#define UPF_NO_TXEN_TEST	((__force upf_t) (1 << 15))
#define UPF_MAGIC_MULTIPLIER	((__force upf_t) (1 << 16))
#define UPF_CONS_FLOW		((__force upf_t) (1 << 23))
#define UPF_SHARE_IRQ		((__force upf_t) (1 << 24))
/* The exact UART type is known and should not be probed.  */
#define UPF_FIXED_TYPE		((__force upf_t) (1 << 27))
#define UPF_BOOT_AUTOCONF	((__force upf_t) (1 << 28))
#define UPF_FIXED_PORT		((__force upf_t) (1 << 29))
#define UPF_DEAD		((__force upf_t) (1 << 30))
#define UPF_IOREMAP		((__force upf_t) (1 << 31))

#define UPF_CHANGE_MASK		((__force upf_t) (0x17fff))
#define UPF_USR_MASK		((__force upf_t) (UPF_SPD_MASK|UPF_LOW_LATENCY))

	unsigned int		mctrl;			/* current modem ctrl settings */
	unsigned int		timeout;		/* character-based timeout */
	unsigned int		type;			/* port type */
	const struct uart_ops	*ops;
	unsigned int		custom_divisor;
	unsigned int		line;			/* port index */
	resource_size_t		mapbase;		/* for ioremap */
	struct device		*dev;			/* parent device */
	unsigned char		hub6;			/* this should be in the 8250 driver */
	unsigned char		suspended;
	unsigned char		unused[2];
	void			*private_data;		/* generic platform data pointer */
};

在serial_core.c 中，提供了下面一个函数来 添加一个端口: uart_add_one_port（）函数。在uart_register_dirver之后，uart_add_one_port 一个重要作用就是 封装了  tty_register_device( );

int uart_add_one_port(struct uart_driver *drv, struct uart_port *port)
{
	struct uart_state *state;
	int ret = 0;
	struct device *tty_dev;

	BUG_ON(in_interrupt());

	if (port->line >= drv->nr)
		return -EINVAL;

	state = drv->state + port->line;

	mutex_lock(&port_mutex);
	mutex_lock(&state->mutex);
	if (state->port) {
		ret = -EINVAL;
		goto out;
	}

	state->port = port;
	state->pm_state = -1;

	port->cons = drv->cons;
	port->info = &state->info;

	/*
	 * If this port is a console, then the spinlock is already
	 * initialised.
	 */
	if (!(uart_console(port) && (port->cons->flags & CON_ENABLED))) {
		spin_lock_init(&port->lock);
		lockdep_set_class(&port->lock, &port_lock_key);
	}

	uart_configure_port(drv, state, port);

	/*
	 * Register the port whether it's detected or not.  This allows
	 * setserial to be used to alter this ports parameters.
	 */
	tty_dev = tty_register_device(drv->tty_driver, port->line, port->dev);
	if (likely(!IS_ERR(tty_dev))) {
		device_init_wakeup(tty_dev, 1);
		device_set_wakeup_enable(tty_dev, 0);
	} else
		printk(KERN_ERR "Cannot register tty device on line %d\n",
		       port->line);

	/*
	 * Ensure UPF_DEAD is not set.
	 */
	port->flags &= ~UPF_DEAD;

 out:
	mutex_unlock(&state->mutex);
	mutex_unlock(&port_mutex);

	return ret;
}

 

uart_ops定义了一系列的操作，如果说，tty_operation对于串口还比较抽象的话，那么 uart_ops则直接面向  了 串口的UART 。这非常类似于面向对象中的 基类和派生类的关系。

struct uart_ops {
	unsigned int	(*tx_empty)(struct uart_port *);
	void		(*set_mctrl)(struct uart_port *, unsigned int mctrl);
	unsigned int	(*get_mctrl)(struct uart_port *);
	void		(*stop_tx)(struct uart_port *);
	void		(*start_tx)(struct uart_port *);
	void		(*send_xchar)(struct uart_port *, char ch);
	void		(*stop_rx)(struct uart_port *);
	void		(*enable_ms)(struct uart_port *);
	void		(*break_ctl)(struct uart_port *, int ctl);
	int		(*startup)(struct uart_port *);
	void		(*shutdown)(struct uart_port *);
	void		(*flush_buffer)(struct uart_port *);
	void		(*set_termios)(struct uart_port *, struct ktermios *new,
				       struct ktermios *old);
	void		(*set_ldisc)(struct uart_port *);
	void		(*pm)(struct uart_port *, unsigned int state,
			      unsigned int oldstate);
	int		(*set_wake)(struct uart_port *, unsigned int state);
	void		(*wake_peer)(struct uart_port *);

	/*
	 * Return a string describing the type of the port
	 */
	const char *(*type)(struct uart_port *);

	/*
	 * Release IO and memory resources used by the port.
	 * This includes iounmap if necessary.
	 */
	void		(*release_port)(struct uart_port *);

	/*
	 * Request IO and memory resources used by the port.
	 * This includes iomapping the port if necessary.
	 */
	int		(*request_port)(struct uart_port *);
	void		(*config_port)(struct uart_port *, int);
	int		(*verify_port)(struct uart_port *, struct serial_struct *);
	int		(*ioctl)(struct uart_port *, unsigned int, unsigned long);
#ifdef CONFIG_CONSOLE_POLL
	void	(*poll_put_char)(struct uart_port *, unsigned char);
	int		(*poll_get_char)(struct uart_port *);
#endif
};

在 serial_console.ｃ　文件中　定义了　ｔｔｙ＿ｏｐｅｒａｔｉｏｎ的事例，

static const struct tty_operations uart_ops = {
	.open		= uart_open,
	.close		= uart_close,
	.write		= uart_write,
	.put_char	= uart_put_char,
	.flush_chars	= uart_flush_chars,
	.write_room	= uart_write_room,
	.chars_in_buffer= uart_chars_in_buffer,
	.flush_buffer	= uart_flush_buffer,
	.ioctl		= uart_ioctl,
	.throttle	= uart_throttle,
	.unthrottle	= uart_unthrottle,
	.send_xchar	= uart_send_xchar,
	.set_termios	= uart_set_termios,
	.set_ldisc	= uart_set_ldisc,
	.stop		= uart_stop,
	.start		= uart_start,
	.hangup		= uart_hangup,
	.break_ctl	= uart_break_ctl,
	.wait_until_sent= uart_wait_until_sent,
#ifdef CONFIG_PROC_FS
	.read_proc	= uart_read_proc,
#endif
	.tiocmget	= uart_tiocmget,
	.tiocmset	= uart_tiocmset,
#ifdef CONFIG_CONSOLE_POLL
	.poll_init	= uart_poll_init,
	.poll_get_char	= uart_poll_get_char,
	.poll_put_char	= uart_poll_put_char,
#endif
};

这些函数会借助　ｕａｒ＿ｏｐｓ结构体中的成员来完成具体的操作。

比如：：ｔｔｙ＿ｏｐｅｒａｔｉｏｎｓ的　ｕａｒｔ＿ｓｅｎｄ＿ｘｃｈａｒ（）成员函数利用了　ｕａｒｔ＿ｏｐｓ结构体的ｓｔａｒ＿ｔｘ来进行初始化。

static void uart_send_xchar(struct tty_struct *tty, char ch)
{
	struct uart_state *state = tty->driver_data;
	struct uart_port *port = state->port;
	unsigned long flags;

	if (port->ops->send_xchar)
		port->ops->send_xchar(port, ch);
	else {
		port->x_char = ch;
		if (ch) {
			spin_lock_irqsave(&port->lock, flags);
			port->ops->start_tx(port);
			spin_unlock_irqrestore(&port->lock, flags);
		}
	}
}

在使用了串口核心层ｔｔｙ接口后，一个串口的要完成的主要工作是

１＼　定义ｕａｒｔ＿ｄｉｖｅｒ　　ｕａｒｔ＿ｏｐｓ　ｕａｒｔ＿ｐｏｒｔ

２＼　ｕａｒｔ＿ｒｅｇｉｓｔｅｒ＿ｄｉｖｅｒ（）　ｕａｒｔ＿ａｄｄ＿ｏｎｅ＿ｐｏｒｔ，注册驱动并添加端口。

３＼　根据具体的ｄａｔａｓｈｅｅｔ　实现　ｕａｒｔ＿ｏｐｓ中的成员。这些函数成了实现ＵＡＲＴ驱动的主体工作。

下面根据这三部来分析　Ｓ３Ｃ６４１０的串口驱动：

１＼　Ｓ３Ｃ６４１０具有４路高速串口。具体见开发板硬件手册。

在ｓａｍｓｕｎｇ．ｃ文件，在官方下的内核改文件已经添加了进来。

static int __init s3c24xx_serial_modinit(void)
{
	int ret;

	ret = uart_register_driver(&s3c24xx_uart_drv);
	if (ret < 0) {
		printk(KERN_ERR "failed to register UART driver\n");
		return -1;
	}

	return 0;
}

 

但是　在同一目录下的　Ｓ３Ｃ６４００。.Ｃ　文件并不存在。

static int __init s3c6400_serial_init(void)
{
	return s3c24xx_serial_init(&s3c6400_serial_drv, &s3c6400_uart_inf);
}

－－＞

static struct platform_driver s3c6400_serial_drv = {
	.probe		= s3c6400_serial_probe,
	.remove		= s3c24xx_serial_remove,
	.driver		= {
		.name	= "s3c6400-uart",
		.owner	= THIS_MODULE,
	},
}

 

static int s3c6400_serial_probe(struct platform_device *dev)
{
	dbg("s3c6400_serial_probe: dev=%p\n", dev);
	return s3c24xx_serial_probe(dev, &s3c6400_uart_inf);
}

 

int s3c24xx_serial_probe(struct platform_device *dev,
			 struct s3c24xx_uart_info *info)
{
	struct s3c24xx_uart_port *ourport;
	int ret;

	dbg("s3c24xx_serial_probe(%p, %p) %d\n", dev, info, probe_index);

	ourport = &s3c24xx_serial_ports[probe_index];
	probe_index++;

	dbg("%s: initialising port %p...\n", __func__, ourport);

	ret = s3c24xx_serial_init_port(ourport, info, dev);
	if (ret < 0)
		goto probe_err;

	dbg("%s: adding port\n", __func__);
	uart_add_one_port(&s3c24xx_uart_drv, &ourport->port);
	platform_set_drvdata(dev, &ourport->port);

	ret = device_create_file(&dev->dev, &dev_attr_clock_source);
	if (ret < 0)
		printk(KERN_ERR "%s: failed to add clksrc attr.\n", __func__);

	ret = s3c24xx_serial_cpufreq_register(ourport);
	if (ret < 0)
		dev_err(&dev->dev, "failed to add cpufreq notifier\n");

	return 0;

 probe_err:
	return ret;
}

 

被添加的　ｕａｒｔ＿ｐｏｒｔ　ｕａｒｔ＿ｏｐｓ成员　定义在　ｓａｍｓｕｎｇ．ｃ文件中

static struct uart_ops s3c24xx_serial_ops = {
	.pm		= s3c24xx_serial_pm,
	.tx_empty	= s3c24xx_serial_tx_empty,
	.get_mctrl	= s3c24xx_serial_get_mctrl,
	.set_mctrl	= s3c24xx_serial_set_mctrl,
	.stop_tx	= s3c24xx_serial_stop_tx,
	.start_tx	= s3c24xx_serial_start_tx,
	.stop_rx	= s3c24xx_serial_stop_rx,
	.enable_ms	= s3c24xx_serial_enable_ms,
	.break_ctl	= s3c24xx_serial_break_ctl,
	.startup	= s3c24xx_serial_startup,
	.shutdown	= s3c24xx_serial_shutdown,
	.set_termios	= s3c24xx_serial_set_termios,
	.type		= s3c24xx_serial_type,
	.release_port	= s3c24xx_serial_release_port,
	.request_port	= s3c24xx_serial_request_port,
	.config_port	= s3c24xx_serial_config_port,
	.verify_port	= s3c24xx_serial_verify_port,
};

从源代码中发现：

tatic struct s3c24xx_uart_port s3c24xx_serial_ports[CONFIG_SERIAL_SAMSUNG_UARTS] = {
	[0] = {
		.port = {
			.lock		= __SPIN_LOCK_UNLOCKED(s3c24xx_serial_ports[0].port.lock),
			.iotype		= UPIO_MEM,
			.irq		= IRQ_S3CUART_RX0,
			.uartclk	= 0,
			.fifosize	= 16,
			.ops		= &s3c24xx_serial_ops,
			.flags		= UPF_BOOT_AUTOCONF,
			.line		= 0,
		}
	},
	[1] = {
		.port = {
			.lock		= __SPIN_LOCK_UNLOCKED(s3c24xx_serial_ports[1].port.lock),
			.iotype		= UPIO_MEM,
			.irq		= IRQ_S3CUART_RX1,
			.uartclk	= 0,
			.fifosize	= 16,
			.ops		= &s3c24xx_serial_ops,
			.flags		= UPF_BOOT_AUTOCONF,
			.line		= 1,
		}
	},
#if CONFIG_SERIAL_SAMSUNG_UARTS > 2

	[2] = {
		.port = {
			.lock		= __SPIN_LOCK_UNLOCKED(s3c24xx_serial_ports[2].port.lock),
			.iotype		= UPIO_MEM,
			.irq		= IRQ_S3CUART_RX2,
			.uartclk	= 0,
			.fifosize	= 16,
			.ops		= &s3c24xx_serial_ops,
			.flags		= UPF_BOOT_AUTOCONF,
			.line		= 2,
		}
	},
#endif
#if CONFIG_SERIAL_SAMSUNG_UARTS > 3
	[3] = {
		.port = {
			.lock		= __SPIN_LOCK_UNLOCKED(s3c24xx_serial_ports[3].port.lock),
			.iotype		= UPIO_MEM,
			.irq		= IRQ_S3CUART_RX3,
			.uartclk	= 0,
			.fifosize	= 16,
			.ops		= &s3c24xx_serial_ops,
			.flags		= UPF_BOOT_AUTOCONF,
			.line		= 3,
		}
	}
#endif
};