specialix.c

来自「linux 内核源代码」· C语言 代码 · 共 2,562 行 · 第 1/5 页

		func_exit();
		return;
	}

	bp = port_Board(port);
	if ((tty->count == 1) && (port->count != 1)) {
		printk(KERN_ERR "sx%d: sx_close: bad port count;"
		       " tty->count is 1, port count is %d\n",
		       board_No(bp), port->count);
		port->count = 1;
	}

	if (port->count > 1) {
		port->count--;
		bp->count--;

		spin_unlock_irqrestore(&port->lock, flags);

		func_exit();
		return;
	}
	port->flags |= ASYNC_CLOSING;
	/*
	 * Now we wait for the transmit buffer to clear; and we notify
	 * the line discipline to only process XON/XOFF characters.
	 */
	tty->closing = 1;
	spin_unlock_irqrestore(&port->lock, flags);
	dprintk (SX_DEBUG_OPEN, "Closing\n");
	if (port->closing_wait != ASYNC_CLOSING_WAIT_NONE) {
		tty_wait_until_sent(tty, port->closing_wait);
	}
	/*
	 * At this point we stop accepting input.  To do this, we
	 * disable the receive line status interrupts, and tell the
	 * interrupt driver to stop checking the data ready bit in the
	 * line status register.
	 */
	dprintk (SX_DEBUG_OPEN, "Closed\n");
	port->IER &= ~IER_RXD;
	if (port->flags & ASYNC_INITIALIZED) {
		port->IER &= ~IER_TXRDY;
		port->IER |= IER_TXEMPTY;
		spin_lock_irqsave(&bp->lock, flags);
		sx_out(bp, CD186x_CAR, port_No(port));
		sx_out(bp, CD186x_IER, port->IER);
		spin_unlock_irqrestore(&bp->lock, flags);
		/*
		 * Before we drop DTR, make sure the UART transmitter
		 * has completely drained; this is especially
		 * important if there is a transmit FIFO!
		 */
		timeout = jiffies+HZ;
		while(port->IER & IER_TXEMPTY) {
			set_current_state (TASK_INTERRUPTIBLE);
			msleep_interruptible(jiffies_to_msecs(port->timeout));
			if (time_after(jiffies, timeout)) {
				printk (KERN_INFO "Timeout waiting for close\n");
				break;
			}
		}

	}

	if (--bp->count < 0) {
		printk(KERN_ERR "sx%d: sx_shutdown_port: bad board count: %d port: %d\n",
		       board_No(bp), bp->count, tty->index);
		bp->count = 0;
	}
	if (--port->count < 0) {
		printk(KERN_ERR "sx%d: sx_close: bad port count for tty%d: %d\n",
		       board_No(bp), port_No(port), port->count);
		port->count = 0;
	}

	sx_shutdown_port(bp, port);
	if (tty->driver->flush_buffer)
		tty->driver->flush_buffer(tty);
	tty_ldisc_flush(tty);
	spin_lock_irqsave(&port->lock, flags);
	tty->closing = 0;
	port->event = 0;
	port->tty = NULL;
	spin_unlock_irqrestore(&port->lock, flags);
	if (port->blocked_open) {
		if (port->close_delay) {
			msleep_interruptible(jiffies_to_msecs(port->close_delay));
		}
		wake_up_interruptible(&port->open_wait);
	}
	port->flags &= ~(ASYNC_NORMAL_ACTIVE|ASYNC_CLOSING);
	wake_up_interruptible(&port->close_wait);

	func_exit();
}


static int sx_write(struct tty_struct * tty,
                    const unsigned char *buf, int count)
{
	struct specialix_port *port = (struct specialix_port *)tty->driver_data;
	struct specialix_board *bp;
	int c, total = 0;
	unsigned long flags;

	func_enter();
	if (sx_paranoia_check(port, tty->name, "sx_write")) {
		func_exit();
		return 0;
	}

	bp = port_Board(port);

	if (!port->xmit_buf) {
		func_exit();
		return 0;
	}

	while (1) {
		spin_lock_irqsave(&port->lock, flags);
		c = min_t(int, count, min(SERIAL_XMIT_SIZE - port->xmit_cnt - 1,
				   SERIAL_XMIT_SIZE - port->xmit_head));
		if (c <= 0) {
			spin_unlock_irqrestore(&port->lock, flags);
			break;
		}
		memcpy(port->xmit_buf + port->xmit_head, buf, c);
		port->xmit_head = (port->xmit_head + c) & (SERIAL_XMIT_SIZE-1);
		port->xmit_cnt += c;
		spin_unlock_irqrestore(&port->lock, flags);

		buf += c;
		count -= c;
		total += c;
	}

	spin_lock_irqsave(&bp->lock, flags);
	if (port->xmit_cnt && !tty->stopped && !tty->hw_stopped &&
	    !(port->IER & IER_TXRDY)) {
		port->IER |= IER_TXRDY;
		sx_out(bp, CD186x_CAR, port_No(port));
		sx_out(bp, CD186x_IER, port->IER);
	}
	spin_unlock_irqrestore(&bp->lock, flags);
	func_exit();

	return total;
}


static void sx_put_char(struct tty_struct * tty, unsigned char ch)
{
	struct specialix_port *port = (struct specialix_port *)tty->driver_data;
	unsigned long flags;
	struct specialix_board  * bp;

	func_enter();

	if (sx_paranoia_check(port, tty->name, "sx_put_char")) {
		func_exit();
		return;
	}
	dprintk (SX_DEBUG_TX, "check tty: %p %p\n", tty, port->xmit_buf);
	if (!port->xmit_buf) {
		func_exit();
		return;
	}
	bp = port_Board(port);
	spin_lock_irqsave(&port->lock, flags);

	dprintk (SX_DEBUG_TX, "xmit_cnt: %d xmit_buf: %p\n", port->xmit_cnt, port->xmit_buf);
	if ((port->xmit_cnt >= SERIAL_XMIT_SIZE - 1) || (!port->xmit_buf)) {
		spin_unlock_irqrestore(&port->lock, flags);
		dprintk (SX_DEBUG_TX, "Exit size\n");
		func_exit();
		return;
	}
	dprintk (SX_DEBUG_TX, "Handle xmit: %p %p\n", port, port->xmit_buf);
	port->xmit_buf[port->xmit_head++] = ch;
	port->xmit_head &= SERIAL_XMIT_SIZE - 1;
	port->xmit_cnt++;
	spin_unlock_irqrestore(&port->lock, flags);

	func_exit();
}


static void sx_flush_chars(struct tty_struct * tty)
{
	struct specialix_port *port = (struct specialix_port *)tty->driver_data;
	unsigned long flags;
	struct specialix_board  * bp = port_Board(port);

	func_enter();

	if (sx_paranoia_check(port, tty->name, "sx_flush_chars")) {
		func_exit();
		return;
	}
	if (port->xmit_cnt <= 0 || tty->stopped || tty->hw_stopped ||
	    !port->xmit_buf) {
		func_exit();
		return;
	}
	spin_lock_irqsave(&bp->lock, flags);
	port->IER |= IER_TXRDY;
	sx_out(port_Board(port), CD186x_CAR, port_No(port));
	sx_out(port_Board(port), CD186x_IER, port->IER);
	spin_unlock_irqrestore(&bp->lock, flags);

	func_exit();
}


static int sx_write_room(struct tty_struct * tty)
{
	struct specialix_port *port = (struct specialix_port *)tty->driver_data;
	int	ret;

	func_enter();

	if (sx_paranoia_check(port, tty->name, "sx_write_room")) {
		func_exit();
		return 0;
	}

	ret = SERIAL_XMIT_SIZE - port->xmit_cnt - 1;
	if (ret < 0)
		ret = 0;

	func_exit();
	return ret;
}


static int sx_chars_in_buffer(struct tty_struct *tty)
{
	struct specialix_port *port = (struct specialix_port *)tty->driver_data;

	func_enter();

	if (sx_paranoia_check(port, tty->name, "sx_chars_in_buffer")) {
		func_exit();
		return 0;
	}
	func_exit();
	return port->xmit_cnt;
}


static void sx_flush_buffer(struct tty_struct *tty)
{
	struct specialix_port *port = (struct specialix_port *)tty->driver_data;
	unsigned long flags;
	struct specialix_board  * bp;

	func_enter();

	if (sx_paranoia_check(port, tty->name, "sx_flush_buffer")) {
		func_exit();
		return;
	}

	bp = port_Board(port);
	spin_lock_irqsave(&port->lock, flags);
	port->xmit_cnt = port->xmit_head = port->xmit_tail = 0;
	spin_unlock_irqrestore(&port->lock, flags);
	tty_wakeup(tty);

	func_exit();
}


static int sx_tiocmget(struct tty_struct *tty, struct file *file)
{
	struct specialix_port *port = (struct specialix_port *)tty->driver_data;
	struct specialix_board * bp;
	unsigned char status;
	unsigned int result;
	unsigned long flags;

	func_enter();

	if (sx_paranoia_check(port, tty->name, __FUNCTION__)) {
		func_exit();
		return -ENODEV;
	}

	bp = port_Board(port);
	spin_lock_irqsave (&bp->lock, flags);
	sx_out(bp, CD186x_CAR, port_No(port));
	status = sx_in(bp, CD186x_MSVR);
	spin_unlock_irqrestore(&bp->lock, flags);
	dprintk (SX_DEBUG_INIT, "Got msvr[%d] = %02x, car = %d.\n",
		port_No(port), status, sx_in (bp, CD186x_CAR));
	dprintk (SX_DEBUG_INIT, "sx_port = %p, port = %p\n", sx_port, port);
	if (SX_CRTSCTS(port->tty)) {
		result  = /*   (status & MSVR_RTS) ? */ TIOCM_DTR /* : 0) */
		          |   ((status & MSVR_DTR) ? TIOCM_RTS : 0)
		          |   ((status & MSVR_CD)  ? TIOCM_CAR : 0)
		          |/* ((status & MSVR_DSR) ? */ TIOCM_DSR /* : 0) */
		          |   ((status & MSVR_CTS) ? TIOCM_CTS : 0);
	} else {
		result  = /*   (status & MSVR_RTS) ? */ TIOCM_RTS /* : 0) */
		          |   ((status & MSVR_DTR) ? TIOCM_DTR : 0)
		          |   ((status & MSVR_CD)  ? TIOCM_CAR : 0)
		          |/* ((status & MSVR_DSR) ? */ TIOCM_DSR /* : 0) */
		          |   ((status & MSVR_CTS) ? TIOCM_CTS : 0);
	}

	func_exit();

	return result;
}


static int sx_tiocmset(struct tty_struct *tty, struct file *file,
		       unsigned int set, unsigned int clear)
{
	struct specialix_port *port = (struct specialix_port *)tty->driver_data;
	unsigned long flags;
	struct specialix_board *bp;

	func_enter();

	if (sx_paranoia_check(port, tty->name, __FUNCTION__)) {
		func_exit();
		return -ENODEV;
	}

	bp = port_Board(port);

	spin_lock_irqsave(&port->lock, flags);
   /*	if (set & TIOCM_RTS)
		port->MSVR |= MSVR_RTS; */
   /*   if (set & TIOCM_DTR)
		port->MSVR |= MSVR_DTR; */

	if (SX_CRTSCTS(port->tty)) {
		if (set & TIOCM_RTS)
			port->MSVR |= MSVR_DTR;
	} else {
		if (set & TIOCM_DTR)
			port->MSVR |= MSVR_DTR;
	}

  /*	if (clear & TIOCM_RTS)
		port->MSVR &= ~MSVR_RTS; */
  /*    if (clear & TIOCM_DTR)
		port->MSVR &= ~MSVR_DTR; */
	if (SX_CRTSCTS(port->tty)) {
		if (clear & TIOCM_RTS)
			port->MSVR &= ~MSVR_DTR;
	} else {
		if (clear & TIOCM_DTR)
			port->MSVR &= ~MSVR_DTR;
	}
	spin_lock_irqsave(&bp->lock, flags);
	sx_out(bp, CD186x_CAR, port_No(port));
	sx_out(bp, CD186x_MSVR, port->MSVR);
	spin_unlock_irqrestore(&bp->lock, flags);
	spin_unlock_irqrestore(&port->lock, flags);
	func_exit();
	return 0;
}


static inline void sx_send_break(struct specialix_port * port, unsigned long length)
{
	struct specialix_board *bp = port_Board(port);
	unsigned long flags;

	func_enter();

	spin_lock_irqsave (&port->lock, flags);
	port->break_length = SPECIALIX_TPS / HZ * length;
	port->COR2 |= COR2_ETC;
	port->IER  |= IER_TXRDY;
	spin_lock_irqsave(&bp->lock, flags);
	sx_out(bp, CD186x_CAR, port_No(port));
	sx_out(bp, CD186x_COR2, port->COR2);
	sx_out(bp, CD186x_IER, port->IER);
	spin_unlock_irqrestore(&bp->lock, flags);
	spin_unlock_irqrestore (&port->lock, flags);
	sx_wait_CCR(bp);
	spin_lock_irqsave(&bp->lock, flags);
	sx_out(bp, CD186x_CCR, CCR_CORCHG2);
	spin_unlock_irqrestore(&bp->lock, flags);
	sx_wait_CCR(bp);

	func_exit();
}


static inline int sx_set_serial_info(struct specialix_port * port,
                                     struct serial_struct __user * newinfo)
{
	struct serial_struct tmp;
	struct specialix_board *bp = port_Board(port);
	int change_speed;

	func_enter();
	/*
	if (!access_ok(VERIFY_READ, (void *) newinfo, sizeof(tmp))) {
		func_exit();
		return -EFAULT;
	}
	*/
	if (copy_from_user(&tmp, newinfo, sizeof(tmp))) {
		func_enter();
		return -EFAULT;
	}

#if 0
	if ((tmp.irq != bp->irq) ||
	    (tmp.port != bp->base) ||
	    (tmp.type != PORT_CIRRUS) ||
	    (tmp.baud_base != (SX_OSCFREQ + CD186x_TPC/2) / CD186x_TPC) ||
	    (tmp.custom_divisor != 0) ||
	    (tmp.xmit_fifo_size != CD186x_NFIFO) ||
	    (tmp.flags & ~SPECIALIX_LEGAL_FLAGS)) {
		func_exit();
		return -EINVAL;
	}
#endif

	change_speed = ((port->flags & ASYNC_SPD_MASK) !=
			(tmp.flags & ASYNC_SPD_MASK));
	change_speed |= (tmp.custom_divisor != port->custom_divisor);

	if (!capable(CAP_SYS_ADMIN)) {
		if ((tmp.close_delay != port->close_delay) ||
		    (tmp.closing_wait != port->closing_wait) ||
		    ((tmp.flags & ~ASYNC_USR_MASK) !=
		     (port->flags & ~ASYNC_USR_MASK))) {
			func_exit();
			return -EPERM;
		}
		port->flags = ((port->flags & ~ASYNC_USR_MASK) |
		                  (tmp.flags & ASYNC_USR_MASK));
		port->custom_divisor = tmp.custom_divisor;
	} else {
		port->flags = ((port->flags & ~ASYNC_FLAGS) |
		                  (tmp.flags & ASYNC_FLAGS));
		port->close_delay = tmp.close_delay;
		port->closing_wait = tmp.closing_wait;
		port->custom_divisor = tmp.custom_divisor;
	}
	if (change_speed) {
		sx_change_speed(bp, port);
	}
	func_exit();
	return 0;
}


static inline int sx_get_serial_info(struct specialix_port * port,
				     struct serial_struct __user *retinfo)
{
	struct serial_struct tmp;
	struct specialix_board *bp = port_Board(port);

	func_enter();

	/*
	if (!access_ok(VERIFY_WRITE, (void *) retinfo, sizeof(tmp)))
		return -EFAULT;
	*/

	memset(&tmp, 0, sizeof(tmp));
	tmp.type = PORT_CIRRUS;
	tmp.line = port - sx_port;
	tmp.port = bp->base;
	tmp.irq  = bp->irq;
	tmp.flags = port->flags;
	tmp.baud_base = (SX_OSCFREQ + CD186x_TPC/2) / CD186x_TPC;
	tmp.close_delay = port->close_delay * HZ/100;
	tmp.closing_wait = port->closing_wait * HZ/100;
	tmp.custom_divisor =  port->custom_divisor;
	tmp.xmit_fifo_size = CD186x_NFIFO;
	if (copy_to_user(retinfo, &tmp, sizeof(tmp))) {
		func_exit();
		return -EFAULT;
	}

	func_exit();
	return 0;
}


static int sx_ioctl(struct tty_struct * tty, struct file * filp,
                    unsigned int cmd, unsigned long arg)
{
	struct specialix_port *port = (struct specialix_port *)tty->driver_data;
	int retval;
	void __user *argp = (void __user *)arg;

	func_enter();

	if (sx_paranoia_check(port, tty->name, "sx_ioctl")) {
		func_exit();
		return -ENODEV;
	}

	switch (cmd) {
	 case TCSBRK:	/* SVID version: non-zero arg --> no break */
		retval = tty_check_change(tty);
		if (retval) {
			func_exit();
			return retval;
		}
		tty_wait_until_sent(tty, 0);
		if (!arg)