synclink_cs.c

这个linux源代码是很全面的~基本完整了~使用c编译的~由于时间问题我没有亲自测试~但就算用来做参考资料也是非常好的

	}
}

/* Signal remote device to stop throttling send data (our receive data)
 */
static void mgslpc_unthrottle(struct tty_struct * tty)
{
	MGSLPC_INFO *info = (MGSLPC_INFO *)tty->driver_data;
	unsigned long flags;
	
	if (debug_level >= DEBUG_LEVEL_INFO)
		printk("%s(%d):mgslpc_unthrottle(%s) entry\n",
			 __FILE__,__LINE__, info->device_name );

	if (mgslpc_paranoia_check(info, tty->device, "mgslpc_unthrottle"))
		return;
	
	if (I_IXOFF(tty)) {
		if (info->x_char)
			info->x_char = 0;
		else
			mgslpc_send_xchar(tty, START_CHAR(tty));
	}
	
 	if (tty->termios->c_cflag & CRTSCTS) {
		spin_lock_irqsave(&info->lock,flags);
		info->serial_signals |= SerialSignal_RTS;
	 	set_signals(info);
		spin_unlock_irqrestore(&info->lock,flags);
	}
}

/* get the current serial statistics
 */
static int get_stats(MGSLPC_INFO * info, struct mgsl_icount *user_icount)
{
	int err;
	if (debug_level >= DEBUG_LEVEL_INFO)
		printk("get_params(%s)\n", info->device_name);
	COPY_TO_USER(err,user_icount, &info->icount, sizeof(struct mgsl_icount));
	if (err)
		return -EFAULT;
	return 0;
}

/* get the current serial parameters
 */
static int get_params(MGSLPC_INFO * info, MGSL_PARAMS *user_params)
{
	int err;
	if (debug_level >= DEBUG_LEVEL_INFO)
		printk("get_params(%s)\n", info->device_name);
	COPY_TO_USER(err,user_params, &info->params, sizeof(MGSL_PARAMS));
	if (err)
		return -EFAULT;
	return 0;
}

/* set the serial parameters
 * 	
 * Arguments:
 * 
 * 	info		pointer to device instance data
 * 	new_params	user buffer containing new serial params
 *
 * Returns:	0 if success, otherwise error code
 */
static int set_params(MGSLPC_INFO * info, MGSL_PARAMS *new_params)
{
 	unsigned long flags;
	MGSL_PARAMS tmp_params;
	int err;
 
	if (debug_level >= DEBUG_LEVEL_INFO)
		printk("%s(%d):set_params %s\n", __FILE__,__LINE__,
			info->device_name );
	COPY_FROM_USER(err,&tmp_params, new_params, sizeof(MGSL_PARAMS));
	if (err) {
		if ( debug_level >= DEBUG_LEVEL_INFO )
			printk( "%s(%d):set_params(%s) user buffer copy failed\n",
				__FILE__,__LINE__,info->device_name);
		return -EFAULT;
	}
	
	spin_lock_irqsave(&info->lock,flags);
	memcpy(&info->params,&tmp_params,sizeof(MGSL_PARAMS));
	spin_unlock_irqrestore(&info->lock,flags);
	
 	mgslpc_change_params(info);
	
	return 0;
}

static int get_txidle(MGSLPC_INFO * info, int*idle_mode)
{
	int err;
	if (debug_level >= DEBUG_LEVEL_INFO)
		printk("get_txidle(%s)=%d\n", info->device_name, info->idle_mode);
	COPY_TO_USER(err,idle_mode, &info->idle_mode, sizeof(int));
	if (err)
		return -EFAULT;
	return 0;
}

static int set_txidle(MGSLPC_INFO * info, int idle_mode)
{
 	unsigned long flags;
	if (debug_level >= DEBUG_LEVEL_INFO)
		printk("set_txidle(%s,%d)\n", info->device_name, idle_mode);
	spin_lock_irqsave(&info->lock,flags);
	info->idle_mode = idle_mode;
	tx_set_idle(info);
	spin_unlock_irqrestore(&info->lock,flags);
	return 0;
}

static int get_interface(MGSLPC_INFO * info, int*if_mode)
{
	int err;
	if (debug_level >= DEBUG_LEVEL_INFO)
		printk("get_interface(%s)=%d\n", info->device_name, info->if_mode);
	COPY_TO_USER(err,if_mode, &info->if_mode, sizeof(int));
	if (err)
		return -EFAULT;
	return 0;
}

static int set_interface(MGSLPC_INFO * info, int if_mode)
{
 	unsigned long flags;
	unsigned char val;
	if (debug_level >= DEBUG_LEVEL_INFO)
		printk("set_interface(%s,%d)\n", info->device_name, if_mode);
	spin_lock_irqsave(&info->lock,flags);
	info->if_mode = if_mode;

	val = read_reg(info, PVR) & 0x0f;
	switch (info->if_mode)
	{
	case MGSL_INTERFACE_RS232: val |= PVR_RS232; break;
	case MGSL_INTERFACE_V35:   val |= PVR_V35;   break;
	case MGSL_INTERFACE_RS422: val |= PVR_RS422; break;
	}
	write_reg(info, PVR, val);

	spin_unlock_irqrestore(&info->lock,flags);
	return 0;
}

static int set_txenable(MGSLPC_INFO * info, int enable)
{
 	unsigned long flags;
 
	if (debug_level >= DEBUG_LEVEL_INFO)
		printk("set_txenable(%s,%d)\n", info->device_name, enable);
			
	spin_lock_irqsave(&info->lock,flags);
	if (enable) {
		if (!info->tx_enabled)
			tx_start(info);
	} else {
		if (info->tx_enabled)
			tx_stop(info);
	}
	spin_unlock_irqrestore(&info->lock,flags);
	return 0;
}

static int tx_abort(MGSLPC_INFO * info)
{
 	unsigned long flags;
 
	if (debug_level >= DEBUG_LEVEL_INFO)
		printk("tx_abort(%s)\n", info->device_name);
			
	spin_lock_irqsave(&info->lock,flags);
	if (info->tx_active && info->tx_count &&
	    info->params.mode == MGSL_MODE_HDLC) {
		/* clear data count so FIFO is not filled on next IRQ.
		 * This results in underrun and abort transmission.
		 */
		info->tx_count = info->tx_put = info->tx_get = 0;
		info->tx_aborting = TRUE;
	}
	spin_unlock_irqrestore(&info->lock,flags);
	return 0;
}

static int set_rxenable(MGSLPC_INFO * info, int enable)
{
 	unsigned long flags;
 
	if (debug_level >= DEBUG_LEVEL_INFO)
		printk("set_rxenable(%s,%d)\n", info->device_name, enable);
			
	spin_lock_irqsave(&info->lock,flags);
	if (enable) {
		if (!info->rx_enabled)
			rx_start(info);
	} else {
		if (info->rx_enabled)
			rx_stop(info);
	}
	spin_unlock_irqrestore(&info->lock,flags);
	return 0;
}

/* wait for specified event to occur
 * 	
 * Arguments:	 	info	pointer to device instance data
 * 			mask	pointer to bitmask of events to wait for
 * Return Value:	0 	if successful and bit mask updated with
 *				of events triggerred,
 * 			otherwise error code
 */
static int wait_events(MGSLPC_INFO * info, int * mask_ptr)
{
 	unsigned long flags;
	int s;
	int rc=0;
	struct mgsl_icount cprev, cnow;
	int events;
	int mask;
	struct	_input_signal_events oldsigs, newsigs;
	DECLARE_WAITQUEUE(wait, current);

	COPY_FROM_USER(rc,&mask, mask_ptr, sizeof(int));
	if (rc)
		return  -EFAULT;
		 
	if (debug_level >= DEBUG_LEVEL_INFO)
		printk("wait_events(%s,%d)\n", info->device_name, mask);

	spin_lock_irqsave(&info->lock,flags);

	/* return immediately if state matches requested events */
	get_signals(info);
	s = info->serial_signals;
	events = mask &
		( ((s & SerialSignal_DSR) ? MgslEvent_DsrActive:MgslEvent_DsrInactive) +
 		  ((s & SerialSignal_DCD) ? MgslEvent_DcdActive:MgslEvent_DcdInactive) +
		  ((s & SerialSignal_CTS) ? MgslEvent_CtsActive:MgslEvent_CtsInactive) +
		  ((s & SerialSignal_RI)  ? MgslEvent_RiActive :MgslEvent_RiInactive) );
	if (events) {
		spin_unlock_irqrestore(&info->lock,flags);
		goto exit;
	}

	/* save current irq counts */
	cprev = info->icount;
	oldsigs = info->input_signal_events;
	
	if ((info->params.mode == MGSL_MODE_HDLC) &&
	    (mask & MgslEvent_ExitHuntMode))
		irq_enable(info, CHA, IRQ_EXITHUNT);
	
	set_current_state(TASK_INTERRUPTIBLE);
	add_wait_queue(&info->event_wait_q, &wait);
	
	spin_unlock_irqrestore(&info->lock,flags);
	
	
	for(;;) {
		schedule();
		if (signal_pending(current)) {
			rc = -ERESTARTSYS;
			break;
		}
			
		/* get current irq counts */
		spin_lock_irqsave(&info->lock,flags);
		cnow = info->icount;
		newsigs = info->input_signal_events;
		set_current_state(TASK_INTERRUPTIBLE);
		spin_unlock_irqrestore(&info->lock,flags);

		/* if no change, wait aborted for some reason */
		if (newsigs.dsr_up   == oldsigs.dsr_up   &&
		    newsigs.dsr_down == oldsigs.dsr_down &&
		    newsigs.dcd_up   == oldsigs.dcd_up   &&
		    newsigs.dcd_down == oldsigs.dcd_down &&
		    newsigs.cts_up   == oldsigs.cts_up   &&
		    newsigs.cts_down == oldsigs.cts_down &&
		    newsigs.ri_up    == oldsigs.ri_up    &&
		    newsigs.ri_down  == oldsigs.ri_down  &&
		    cnow.exithunt    == cprev.exithunt   &&
		    cnow.rxidle      == cprev.rxidle) {
			rc = -EIO;
			break;
		}

		events = mask &
			( (newsigs.dsr_up   != oldsigs.dsr_up   ? MgslEvent_DsrActive:0)   +
			  (newsigs.dsr_down != oldsigs.dsr_down ? MgslEvent_DsrInactive:0) +
			  (newsigs.dcd_up   != oldsigs.dcd_up   ? MgslEvent_DcdActive:0)   +
			  (newsigs.dcd_down != oldsigs.dcd_down ? MgslEvent_DcdInactive:0) +
			  (newsigs.cts_up   != oldsigs.cts_up   ? MgslEvent_CtsActive:0)   +
			  (newsigs.cts_down != oldsigs.cts_down ? MgslEvent_CtsInactive:0) +
			  (newsigs.ri_up    != oldsigs.ri_up    ? MgslEvent_RiActive:0)    +
			  (newsigs.ri_down  != oldsigs.ri_down  ? MgslEvent_RiInactive:0)  +
			  (cnow.exithunt    != cprev.exithunt   ? MgslEvent_ExitHuntMode:0) +
			  (cnow.rxidle      != cprev.rxidle     ? MgslEvent_IdleReceived:0) );
		if (events)
			break;
		
		cprev = cnow;
		oldsigs = newsigs;
	}
	
	remove_wait_queue(&info->event_wait_q, &wait);
	set_current_state(TASK_RUNNING);

	if (mask & MgslEvent_ExitHuntMode) {
		spin_lock_irqsave(&info->lock,flags);
		if (!waitqueue_active(&info->event_wait_q))
			irq_disable(info, CHA, IRQ_EXITHUNT);
		spin_unlock_irqrestore(&info->lock,flags);
	}
exit:
	if (rc == 0)
		PUT_USER(rc, events, mask_ptr);
	return rc;
}

static int modem_input_wait(MGSLPC_INFO *info,int arg)
{
 	unsigned long flags;
	int rc;
	struct mgsl_icount cprev, cnow;
	DECLARE_WAITQUEUE(wait, current);

	/* save current irq counts */
	spin_lock_irqsave(&info->lock,flags);
	cprev = info->icount;
	add_wait_queue(&info->status_event_wait_q, &wait);
	set_current_state(TASK_INTERRUPTIBLE);
	spin_unlock_irqrestore(&info->lock,flags);

	for(;;) {
		schedule();
		if (signal_pending(current)) {
			rc = -ERESTARTSYS;
			break;
		}

		/* get new irq counts */
		spin_lock_irqsave(&info->lock,flags);
		cnow = info->icount;
		set_current_state(TASK_INTERRUPTIBLE);
		spin_unlock_irqrestore(&info->lock,flags);

		/* if no change, wait aborted for some reason */
		if (cnow.rng == cprev.rng && cnow.dsr == cprev.dsr &&
		    cnow.dcd == cprev.dcd && cnow.cts == cprev.cts) {
			rc = -EIO;
			break;
		}

		/* check for change in caller specified modem input */
		if ((arg & TIOCM_RNG && cnow.rng != cprev.rng) ||
		    (arg & TIOCM_DSR && cnow.dsr != cprev.dsr) ||
		    (arg & TIOCM_CD  && cnow.dcd != cprev.dcd) ||
		    (arg & TIOCM_CTS && cnow.cts != cprev.cts)) {
			rc = 0;
			break;
		}

		cprev = cnow;
	}
	remove_wait_queue(&info->status_event_wait_q, &wait);
	set_current_state(TASK_RUNNING);
	return rc;
}

/* Return state of the serial control/status signals
 * 	
 * Arguments:	 	info	pointer to device instance data
 * 			value	pointer to int to hold returned info
 * 	
 * Return Value:	0 if success, otherwise error code
 */
static int get_modem_info(MGSLPC_INFO * info, unsigned int *value)
{
	unsigned int result;
 	unsigned long flags;
	int err;
 
	spin_lock_irqsave(&info->lock,flags);
 	get_signals(info);
	spin_unlock_irqrestore(&info->lock,flags);

	result = ((info->serial_signals & SerialSignal_RTS) ? TIOCM_RTS:0) |
		 ((info->serial_signals & SerialSignal_DTR) ? TIOCM_DTR:0) |
		 ((info->serial_signals & SerialSignal_DCD) ? TIOCM_CAR:0) |
		 ((info->serial_signals & SerialSignal_RI)  ? TIOCM_RNG:0) |
		 ((info->serial_signals & SerialSignal_DSR) ? TIOCM_DSR:0) |
		 ((info->serial_signals & SerialSignal_CTS) ? TIOCM_CTS:0);

	if (debug_level >= DEBUG_LEVEL_INFO)
		printk("mgslpc_get_modem_info %s value=%08X\n", info->device_name, result);
			
	PUT_USER(err,result,value);
	return err ? -EFAULT : 0;
}

/* Set the state of the modem control signals (DTR/RTS)
 * 	
 * Arguments:
 * 
 * 	info	pointer to device instance data
 * 	cmd	signal command: TIOCMBIS = set bit TIOCMBIC = clear bit
 *		TIOCMSET = set/clear signal values
 * 	value	bit mask for command
 * 	
 * Return Value:	0 if success, otherwise error code
 */
static int set_modem_info(MGSLPC_INFO * info, unsigned int cmd,
			  unsigned int *value)
{
 	int error;
 	unsigned int arg;
 	unsigned long flags;
 
	if (debug_level >= DEBUG_LEVEL_INFO)
		printk("mgslpc_set_modem_info %s\n", info->device_name);
			
 	GET_USER(error,arg,value);
 	if (error)
 		return error;
		
 	switch (cmd) {
 	case TIOCMBIS: 
 		if (arg & TIOCM_RTS)
 			info->serial_signals |= SerialSignal_RTS;
 		if (arg & TIOCM_DTR)
 			info->serial_signals |= SerialSignal_DTR;
 		break;
 	case TIOCMBIC:
 		if (arg & TIOCM_RTS)
 			info->serial_signals &= ~SerialSignal_RTS;
 		if (arg & TIOCM_DTR)
 			info->serial_signals &= ~SerialSignal_DTR;
 		break;
 	case TIOCMSET:
 		if (arg & TIOCM_RTS)
 			info->serial_signals |= SerialSignal_RTS;
		else
 			info->serial_signals &= ~SerialSignal_RTS;
		
 		if (arg & TIOCM_DTR)
 			info->serial_signals |= SerialSignal_DTR;
		else
 			info->serial_signals &= ~SerialSignal_DTR;
 		break;
 	default:
 		return -EINVAL;
 	}
	
	spin_lock_irqsave(&info->lock,flags);
 	set_signals(info);
	spin_unlock_irqrestore(&info->lock,flags);
	
	return 0;
}

/* Set or clear transmit break condition
 *
 * Arguments:		tty		pointer to tty instance data
 *			break_state	-1=set break condition, 0=clear
 */
static void mgslpc_break(struct tty_struct *tty, int break_state)
{
	MGSLPC_INFO * info = (MGSLPC_INFO *)tty->driver_data;
	unsigned long flags;
	
	if (debug_level >= DEBUG_LEVEL_INFO)
		printk("%s(%d):mgslpc_break(%s,%d)\n",
			 __FILE__,__LINE__, info->device_name, break_state);
			 
	if (mgslpc_paranoia_check(info, tty->device, "mgslpc_break"))
		return;

	spin_lock_irqsave(&info->lock,flags);
 	if (break_state == -1)
		set_reg_bits(info, CHA+DAFO, BIT6);
	else 
		clear_reg_bit