synclink_gt.c

linux 内核源代码

	 * Note: use tight timings here to satisfy the NIST-PCTS.
	 */

	if (info->params.data_rate) {
	       	char_time = info->timeout/(32 * 5);
		if (!char_time)
			char_time++;
	} else
		char_time = 1;

	if (timeout)
		char_time = min_t(unsigned long, char_time, timeout);

	while (info->tx_active) {
		msleep_interruptible(jiffies_to_msecs(char_time));
		if (signal_pending(current))
			break;
		if (timeout && time_after(jiffies, orig_jiffies + timeout))
			break;
	}

exit:
	DBGINFO(("%s wait_until_sent exit\n", info->device_name));
}

static int write_room(struct tty_struct *tty)
{
	struct slgt_info *info = tty->driver_data;
	int ret;

	if (sanity_check(info, tty->name, "write_room"))
		return 0;
	ret = (info->tx_active) ? 0 : HDLC_MAX_FRAME_SIZE;
	DBGINFO(("%s write_room=%d\n", info->device_name, ret));
	return ret;
}

static void flush_chars(struct tty_struct *tty)
{
	struct slgt_info *info = tty->driver_data;
	unsigned long flags;

	if (sanity_check(info, tty->name, "flush_chars"))
		return;
	DBGINFO(("%s flush_chars entry tx_count=%d\n", info->device_name, info->tx_count));

	if (info->tx_count <= 0 || tty->stopped ||
	    tty->hw_stopped || !info->tx_buf)
		return;

	DBGINFO(("%s flush_chars start transmit\n", info->device_name));

	spin_lock_irqsave(&info->lock,flags);
	if (!info->tx_active && info->tx_count) {
		tx_load(info, info->tx_buf,info->tx_count);
	 	tx_start(info);
	}
	spin_unlock_irqrestore(&info->lock,flags);
}

static void flush_buffer(struct tty_struct *tty)
{
	struct slgt_info *info = tty->driver_data;
	unsigned long flags;

	if (sanity_check(info, tty->name, "flush_buffer"))
		return;
	DBGINFO(("%s flush_buffer\n", info->device_name));

	spin_lock_irqsave(&info->lock,flags);
	if (!info->tx_active)
		info->tx_count = 0;
	spin_unlock_irqrestore(&info->lock,flags);

	tty_wakeup(tty);
}

/*
 * throttle (stop) transmitter
 */
static void tx_hold(struct tty_struct *tty)
{
	struct slgt_info *info = tty->driver_data;
	unsigned long flags;

	if (sanity_check(info, tty->name, "tx_hold"))
		return;
	DBGINFO(("%s tx_hold\n", info->device_name));
	spin_lock_irqsave(&info->lock,flags);
	if (info->tx_enabled && info->params.mode == MGSL_MODE_ASYNC)
	 	tx_stop(info);
	spin_unlock_irqrestore(&info->lock,flags);
}

/*
 * release (start) transmitter
 */
static void tx_release(struct tty_struct *tty)
{
	struct slgt_info *info = tty->driver_data;
	unsigned long flags;

	if (sanity_check(info, tty->name, "tx_release"))
		return;
	DBGINFO(("%s tx_release\n", info->device_name));
	spin_lock_irqsave(&info->lock,flags);
	if (!info->tx_active && info->tx_count) {
		tx_load(info, info->tx_buf, info->tx_count);
	 	tx_start(info);
	}
	spin_unlock_irqrestore(&info->lock,flags);
}

/*
 * Service an IOCTL request
 *
 * Arguments
 *
 * 	tty	pointer to tty instance data
 * 	file	pointer to associated file object for device
 * 	cmd	IOCTL command code
 * 	arg	command argument/context
 *
 * Return 0 if success, otherwise error code
 */
static int ioctl(struct tty_struct *tty, struct file *file,
		 unsigned int cmd, unsigned long arg)
{
	struct slgt_info *info = tty->driver_data;
	struct mgsl_icount cnow;	/* kernel counter temps */
	struct serial_icounter_struct __user *p_cuser;	/* user space */
	unsigned long flags;
	void __user *argp = (void __user *)arg;

	if (sanity_check(info, tty->name, "ioctl"))
		return -ENODEV;
	DBGINFO(("%s ioctl() cmd=%08X\n", info->device_name, cmd));

	if ((cmd != TIOCGSERIAL) && (cmd != TIOCSSERIAL) &&
	    (cmd != TIOCMIWAIT) && (cmd != TIOCGICOUNT)) {
		if (tty->flags & (1 << TTY_IO_ERROR))
		    return -EIO;
	}

	switch (cmd) {
	case MGSL_IOCGPARAMS:
		return get_params(info, argp);
	case MGSL_IOCSPARAMS:
		return set_params(info, argp);
	case MGSL_IOCGTXIDLE:
		return get_txidle(info, argp);
	case MGSL_IOCSTXIDLE:
		return set_txidle(info, (int)arg);
	case MGSL_IOCTXENABLE:
		return tx_enable(info, (int)arg);
	case MGSL_IOCRXENABLE:
		return rx_enable(info, (int)arg);
	case MGSL_IOCTXABORT:
		return tx_abort(info);
	case MGSL_IOCGSTATS:
		return get_stats(info, argp);
	case MGSL_IOCWAITEVENT:
		return wait_mgsl_event(info, argp);
	case TIOCMIWAIT:
		return modem_input_wait(info,(int)arg);
	case MGSL_IOCGIF:
		return get_interface(info, argp);
	case MGSL_IOCSIF:
		return set_interface(info,(int)arg);
	case MGSL_IOCSGPIO:
		return set_gpio(info, argp);
	case MGSL_IOCGGPIO:
		return get_gpio(info, argp);
	case MGSL_IOCWAITGPIO:
		return wait_gpio(info, argp);
	case TIOCGICOUNT:
		spin_lock_irqsave(&info->lock,flags);
		cnow = info->icount;
		spin_unlock_irqrestore(&info->lock,flags);
		p_cuser = argp;
		if (put_user(cnow.cts, &p_cuser->cts) ||
		    put_user(cnow.dsr, &p_cuser->dsr) ||
		    put_user(cnow.rng, &p_cuser->rng) ||
		    put_user(cnow.dcd, &p_cuser->dcd) ||
		    put_user(cnow.rx, &p_cuser->rx) ||
		    put_user(cnow.tx, &p_cuser->tx) ||
		    put_user(cnow.frame, &p_cuser->frame) ||
		    put_user(cnow.overrun, &p_cuser->overrun) ||
		    put_user(cnow.parity, &p_cuser->parity) ||
		    put_user(cnow.brk, &p_cuser->brk) ||
		    put_user(cnow.buf_overrun, &p_cuser->buf_overrun))
			return -EFAULT;
		return 0;
	default:
		return -ENOIOCTLCMD;
	}
	return 0;
}

/*
 * support for 32 bit ioctl calls on 64 bit systems
 */
#ifdef CONFIG_COMPAT
static long get_params32(struct slgt_info *info, struct MGSL_PARAMS32 __user *user_params)
{
	struct MGSL_PARAMS32 tmp_params;

	DBGINFO(("%s get_params32\n", info->device_name));
	tmp_params.mode            = (compat_ulong_t)info->params.mode;
	tmp_params.loopback        = info->params.loopback;
	tmp_params.flags           = info->params.flags;
	tmp_params.encoding        = info->params.encoding;
	tmp_params.clock_speed     = (compat_ulong_t)info->params.clock_speed;
	tmp_params.addr_filter     = info->params.addr_filter;
	tmp_params.crc_type        = info->params.crc_type;
	tmp_params.preamble_length = info->params.preamble_length;
	tmp_params.preamble        = info->params.preamble;
	tmp_params.data_rate       = (compat_ulong_t)info->params.data_rate;
	tmp_params.data_bits       = info->params.data_bits;
	tmp_params.stop_bits       = info->params.stop_bits;
	tmp_params.parity          = info->params.parity;
	if (copy_to_user(user_params, &tmp_params, sizeof(struct MGSL_PARAMS32)))
		return -EFAULT;
	return 0;
}

static long set_params32(struct slgt_info *info, struct MGSL_PARAMS32 __user *new_params)
{
	struct MGSL_PARAMS32 tmp_params;

	DBGINFO(("%s set_params32\n", info->device_name));
	if (copy_from_user(&tmp_params, new_params, sizeof(struct MGSL_PARAMS32)))
		return -EFAULT;

	spin_lock(&info->lock);
	info->params.mode            = tmp_params.mode;
	info->params.loopback        = tmp_params.loopback;
	info->params.flags           = tmp_params.flags;
	info->params.encoding        = tmp_params.encoding;
	info->params.clock_speed     = tmp_params.clock_speed;
	info->params.addr_filter     = tmp_params.addr_filter;
	info->params.crc_type        = tmp_params.crc_type;
	info->params.preamble_length = tmp_params.preamble_length;
	info->params.preamble        = tmp_params.preamble;
	info->params.data_rate       = tmp_params.data_rate;
	info->params.data_bits       = tmp_params.data_bits;
	info->params.stop_bits       = tmp_params.stop_bits;
	info->params.parity          = tmp_params.parity;
	spin_unlock(&info->lock);

 	change_params(info);

	return 0;
}

static long slgt_compat_ioctl(struct tty_struct *tty, struct file *file,
			 unsigned int cmd, unsigned long arg)
{
	struct slgt_info *info = tty->driver_data;
	int rc = -ENOIOCTLCMD;

	if (sanity_check(info, tty->name, "compat_ioctl"))
		return -ENODEV;
	DBGINFO(("%s compat_ioctl() cmd=%08X\n", info->device_name, cmd));

	switch (cmd) {

	case MGSL_IOCSPARAMS32:
		rc = set_params32(info, compat_ptr(arg));
		break;

	case MGSL_IOCGPARAMS32:
		rc = get_params32(info, compat_ptr(arg));
		break;

	case MGSL_IOCGPARAMS:
	case MGSL_IOCSPARAMS:
	case MGSL_IOCGTXIDLE:
	case MGSL_IOCGSTATS:
	case MGSL_IOCWAITEVENT:
	case MGSL_IOCGIF:
	case MGSL_IOCSGPIO:
	case MGSL_IOCGGPIO:
	case MGSL_IOCWAITGPIO:
	case TIOCGICOUNT:
		rc = ioctl(tty, file, cmd, (unsigned long)(compat_ptr(arg)));
		break;

	case MGSL_IOCSTXIDLE:
	case MGSL_IOCTXENABLE:
	case MGSL_IOCRXENABLE:
	case MGSL_IOCTXABORT:
	case TIOCMIWAIT:
	case MGSL_IOCSIF:
		rc = ioctl(tty, file, cmd, arg);
		break;
	}

	DBGINFO(("%s compat_ioctl() cmd=%08X rc=%d\n", info->device_name, cmd, rc));
	return rc;
}
#else
#define slgt_compat_ioctl NULL
#endif /* ifdef CONFIG_COMPAT */

/*
 * proc fs support
 */
static inline int line_info(char *buf, struct slgt_info *info)
{
	char stat_buf[30];
	int ret;
	unsigned long flags;

	ret = sprintf(buf, "%s: IO=%08X IRQ=%d MaxFrameSize=%u\n",
		      info->device_name, info->phys_reg_addr,
		      info->irq_level, info->max_frame_size);

	/* output current serial signal states */
	spin_lock_irqsave(&info->lock,flags);
	get_signals(info);
	spin_unlock_irqrestore(&info->lock,flags);

	stat_buf[0] = 0;
	stat_buf[1] = 0;
	if (info->signals & SerialSignal_RTS)
		strcat(stat_buf, "|RTS");
	if (info->signals & SerialSignal_CTS)
		strcat(stat_buf, "|CTS");
	if (info->signals & SerialSignal_DTR)
		strcat(stat_buf, "|DTR");
	if (info->signals & SerialSignal_DSR)
		strcat(stat_buf, "|DSR");
	if (info->signals & SerialSignal_DCD)
		strcat(stat_buf, "|CD");
	if (info->signals & SerialSignal_RI)
		strcat(stat_buf, "|RI");

	if (info->params.mode != MGSL_MODE_ASYNC) {
		ret += sprintf(buf+ret, "\tHDLC txok:%d rxok:%d",
			       info->icount.txok, info->icount.rxok);
		if (info->icount.txunder)
			ret += sprintf(buf+ret, " txunder:%d", info->icount.txunder);
		if (info->icount.txabort)
			ret += sprintf(buf+ret, " txabort:%d", info->icount.txabort);
		if (info->icount.rxshort)
			ret += sprintf(buf+ret, " rxshort:%d", info->icount.rxshort);
		if (info->icount.rxlong)
			ret += sprintf(buf+ret, " rxlong:%d", info->icount.rxlong);
		if (info->icount.rxover)
			ret += sprintf(buf+ret, " rxover:%d", info->icount.rxover);
		if (info->icount.rxcrc)
			ret += sprintf(buf+ret, " rxcrc:%d", info->icount.rxcrc);
	} else {
		ret += sprintf(buf+ret, "\tASYNC tx:%d rx:%d",
			       info->icount.tx, info->icount.rx);
		if (info->icount.frame)
			ret += sprintf(buf+ret, " fe:%d", info->icount.frame);
		if (info->icount.parity)
			ret += sprintf(buf+ret, " pe:%d", info->icount.parity);
		if (info->icount.brk)
			ret += sprintf(buf+ret, " brk:%d", info->icount.brk);
		if (info->icount.overrun)
			ret += sprintf(buf+ret, " oe:%d", info->icount.overrun);
	}

	/* Append serial signal status to end */
	ret += sprintf(buf+ret, " %s\n", stat_buf+1);

	ret += sprintf(buf+ret, "\ttxactive=%d bh_req=%d bh_run=%d pending_bh=%x\n",
		       info->tx_active,info->bh_requested,info->bh_running,
		       info->pending_bh);

	return ret;
}

/* Called to print information about devices
 */
static int read_proc(char *page, char **start, off_t off, int count,
		     int *eof, void *data)
{
	int len = 0, l;
	off_t	begin = 0;
	struct slgt_info *info;

	len += sprintf(page, "synclink_gt driver:%s\n", driver_version);

	info = slgt_device_list;
	while( info ) {
		l = line_info(page + len, info);
		len += l;
		if (len+begin > off+count)
			goto done;
		if (len+begin < off) {
			begin += len;
			len = 0;
		}
		info = info->next_device;
	}

	*eof = 1;
done:
	if (off >= len+begin)
		return 0;
	*start = page + (off-begin);
	return ((count < begin+len-off) ? count : begin+len-off);
}

/*
 * return count of bytes in transmit buffer
 */
static int chars_in_buffer(struct tty_struct *tty)
{
	struct slgt_info *info = tty->driver_data;
	if (sanity_check(info, tty->name, "chars_in_buffer"))
		return 0;
	DBGINFO(("%s chars_in_buffer()=%d\n", info->device_name, info->tx_count));
	return info->tx_count;
}

/*
 * signal remote device to throttle send data (our receive data)
 */
static void throttle(struct tty_struct * tty)
{
	struct slgt_info *info = tty->driver_data;
	unsigned long flags;

	if (sanity_check(info, tty->name, "throttle"))
		return;
	DBGINFO(("%s throttle\n", info->device_name));
	if (I_IXOFF(tty))
		send_xchar(tty, STOP_CHAR(tty));
 	if (tty->termios->c_cflag & CRTSCTS) {
		spin_lock_irqsave(&info->lock,flags);
		info->signals &= ~SerialSignal_RTS;
	 	set_signals(info);
		spin_unlock_irqrestore(&info->lock,flags);
	}
}

/*
 * signal remote device to stop throttling send data (our receive data)
 */
static void unthrottle(struct tty_struct * tty)
{
	struct slgt_info *info = tty->driver_data;
	unsigned long flags;

	if (sanity_check(info, tty->name, "unthrottle"))
		return;
	DBGINFO(("%s unthrottle\n", info->device_name));
	if (I_IXOFF(tty)) {
		if (info->x_char)
			info->x_char = 0;
		else
			send_xchar(tty, START_CHAR(tty));
	}
 	if (tty->termios->c_cflag & CRTSCTS) {
		spin_lock_irqsave(&info->lock,flags);
		info->signals |= SerialSignal_RTS;
	 	set_signals(info);
		spin_unlock_irqrestore(&info->lock,flags);
	}
}

/*
 * set or clear transmit break condition
 * break_state	-1=set break condition, 0=clear
 */
static void set_break(struct tty_struct *tty, int break_state)
{
	struct slgt_info *info = tty->driver_data;
	unsigned short value;
	unsigned long flags;

	if (sanity_check(info, tty->name, "set_break"))
		return;
	DBGINFO(("%s set_break(%d)\n", info->device_name, break_state));

	spin_lock_irqsave(&info->lock,flags);
	value = rd_reg16(info, TCR);
 	if (break_state == -1)
		value |= BIT6;