ip2main.c

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			(pCh->flags & ASYNC_CLOSING)?"True":"False");
		printk(KERN_DEBUG "OpenBlock: waiting for CD or signal\n");
#endif
#ifdef IP2DEBUG_TRACE
		ip2trace (CHANN, ITRC_OPEN, 3, 2, (pCh->flags & ASYNC_CALLOUT_ACTIVE),
								(pCh->flags & ASYNC_CLOSING) );
#endif
		/* check for signal */
		if (signal_pending(current)) {
			rc = (( pCh->flags & ASYNC_HUP_NOTIFY ) ? -EAGAIN : -ERESTARTSYS);
			break;
		}
		interruptible_sleep_on(&pCh->open_wait);
	}
	--pCh->wopen; //why count?
#ifdef IP2DEBUG_TRACE
	ip2trace (CHANN, ITRC_OPEN, 4, 0 );
#endif
	if (rc != 0 ) {
		return rc;
	}
	pCh->flags |= ASYNC_NORMAL_ACTIVE;

noblock:

	/* first open - Assign termios structure to port */
	if ( tty->count == 1 ) {
		i2QueueCommands(PTYPE_INLINE, pCh, 0, 2, CMD_CTSFL_DSAB, CMD_RTSFL_DSAB);
		if ( pCh->flags & ASYNC_SPLIT_TERMIOS ) {
			if ( tty->driver.subtype == SERIAL_TYPE_NORMAL ) {
				*tty->termios = pCh->NormalTermios;
			} else {
				*tty->termios = pCh->CalloutTermios;
			}
		}
		/* Now we must send the termios settings to the loadware */
		set_params( pCh, NULL );
	}

	/* override previous and never reset ??? */
	pCh->session = current->session;
	pCh->pgrp = current->pgrp;

	/*
	 * Now set any i2lib options. These may go away if the i2lib code ends
	 * up rolled into the mainline.
	 */
	pCh->channelOptions |= CO_NBLOCK_WRITE;

#ifdef IP2DEBUG_OPEN
	printk (KERN_DEBUG "IP2: open completed\n" );
#endif
	serviceOutgoingFifo( pCh->pMyBord );

#ifdef IP2DEBUG_TRACE
	ip2trace (CHANN, ITRC_OPEN, ITRC_RETURN, 0 );
#endif
	return 0;
}

/******************************************************************************/
/* Function:   ip2_close()                                                    */
/* Parameters: Pointer to tty structure                                       */
/*             Pointer to file structure                                      */
/* Returns:    Nothing                                                        */
/*                                                                            */
/* Description:                                                               */
/*                                                                            */
/*                                                                            */
/******************************************************************************/
static void
ip2_close( PTTY tty, struct file *pFile )
{
	i2ChanStrPtr  pCh = tty->driver_data;

	if ( !pCh ) {
		return;
	}

#ifdef IP2DEBUG_TRACE
	ip2trace (CHANN, ITRC_CLOSE, ITRC_ENTER, 0 );
#endif

#ifdef IP2DEBUG_OPEN
	printk(KERN_DEBUG "IP2:close ttyF%02X:\n",MINOR(tty->device));
#endif

	if ( tty_hung_up_p ( pFile ) ) {
		MOD_DEC_USE_COUNT;

#ifdef IP2DEBUG_TRACE
		ip2trace (CHANN, ITRC_CLOSE, 2, 1, 2 );
#endif
		return;
	}
	if ( tty->count > 1 ) { /* not the last close */
		MOD_DEC_USE_COUNT;
#ifdef IP2DEBUG_TRACE
		ip2trace (CHANN, ITRC_CLOSE, 2, 1, 3 );
#endif
		return;
	}
	pCh->flags |= ASYNC_CLOSING;	// last close actually

	/*
	 * Save the termios structure, since this port may have separate termios
	 * for callout and dialin.
	 */
	if (pCh->flags & ASYNC_NORMAL_ACTIVE)
		pCh->NormalTermios = *tty->termios;
	if (pCh->flags & ASYNC_CALLOUT_ACTIVE)
		pCh->CalloutTermios = *tty->termios;

	tty->closing = 1;

	if (pCh->ClosingWaitTime != ASYNC_CLOSING_WAIT_NONE) {
		/*
		 * Before we drop DTR, make sure the transmitter has completely drained.
		 * This uses an timeout, after which the close
		 * completes.
		 */
		ip2_wait_until_sent(tty, pCh->ClosingWaitTime );
	}
	/*
	 * At this point we stop accepting input. Here we flush the channel
	 * input buffer which will allow the board to send up more data. Any
	 * additional input is tossed at interrupt/poll time.
	 */
	i2InputFlush( pCh );

	/* disable DSS reporting */
	i2QueueCommands(PTYPE_INLINE, pCh, 100, 4,
				CMD_DCD_NREP, CMD_CTS_NREP, CMD_DSR_NREP, CMD_RI_NREP);
	if ( !tty || (tty->termios->c_cflag & HUPCL) ) {
		i2QueueCommands(PTYPE_INLINE, pCh, 100, 2, CMD_RTSDN, CMD_DTRDN);
		pCh->dataSetOut &= ~(I2_DTR | I2_RTS);
		i2QueueCommands( PTYPE_INLINE, pCh, 100, 1, CMD_PAUSE(25));
	}

	serviceOutgoingFifo ( pCh->pMyBord );

	if ( tty->driver.flush_buffer ) 
		tty->driver.flush_buffer(tty);
	if ( tty->ldisc.flush_buffer )  
		tty->ldisc.flush_buffer(tty);
	tty->closing = 0;
	
	pCh->pTTY = NULL;

	if (pCh->wopen) {
		if (pCh->ClosingDelay) {
			current->state = TASK_INTERRUPTIBLE;
			schedule_timeout(pCh->ClosingDelay);
		}
		wake_up_interruptible(&pCh->open_wait);
	}

	pCh->flags &=~(ASYNC_NORMAL_ACTIVE|ASYNC_CALLOUT_ACTIVE|ASYNC_CLOSING);
	wake_up_interruptible(&pCh->close_wait);

#ifdef IP2DEBUG_OPEN
	DBG_CNT("ip2_close: after wakeups--");
#endif

	MOD_DEC_USE_COUNT;

#ifdef IP2DEBUG_TRACE
	ip2trace (CHANN, ITRC_CLOSE, ITRC_RETURN, 1, 1 );
#endif
	return;
}

/******************************************************************************/
/* Function:   ip2_hangup()                                                   */
/* Parameters: Pointer to tty structure                                       */
/* Returns:    Nothing                                                        */
/*                                                                            */
/* Description:                                                               */
/*                                                                            */
/*                                                                            */
/******************************************************************************/
static void
ip2_hangup ( PTTY tty )
{
	i2ChanStrPtr  pCh = tty->driver_data;

#ifdef IP2DEBUG_TRACE
	ip2trace (CHANN, ITRC_HANGUP, ITRC_ENTER, 0 );
#endif

	ip2_flush_buffer(tty);

	/* disable DSS reporting */

	i2QueueCommands(PTYPE_BYPASS, pCh, 0, 1, CMD_DCD_NREP);
	i2QueueCommands(PTYPE_INLINE, pCh, 0, 2, CMD_CTSFL_DSAB, CMD_RTSFL_DSAB);
	if ( !tty || (tty->termios->c_cflag & HUPCL) ) {
		i2QueueCommands(PTYPE_BYPASS, pCh, 0, 2, CMD_RTSDN, CMD_DTRDN);
		pCh->dataSetOut &= ~(I2_DTR | I2_RTS);
		i2QueueCommands( PTYPE_INLINE, pCh, 100, 1, CMD_PAUSE(25));
	}
	i2QueueCommands(PTYPE_INLINE, pCh, 1, 3, 
				CMD_CTS_NREP, CMD_DSR_NREP, CMD_RI_NREP);
	serviceOutgoingFifo ( pCh->pMyBord );

	wake_up_interruptible ( &pCh->delta_msr_wait );

	pCh->flags &= ~(ASYNC_NORMAL_ACTIVE|ASYNC_CALLOUT_ACTIVE);
	pCh->pTTY = NULL;
	wake_up_interruptible ( &pCh->open_wait );

#ifdef IP2DEBUG_TRACE
	ip2trace (CHANN, ITRC_HANGUP, ITRC_RETURN, 0 );
#endif
}

/******************************************************************************/
/******************************************************************************/
/* Device Output Section                                                      */
/******************************************************************************/
/******************************************************************************/

/******************************************************************************/
/* Function:   ip2_write()                                                    */
/* Parameters: Pointer to tty structure                                       */
/*             Flag denoting data is in user (1) or kernel (0) space          */
/*             Pointer to data                                                */
/*             Number of bytes to write                                       */
/* Returns:    Number of bytes actually written                               */
/*                                                                            */
/* Description: (MANDATORY)                                                   */
/*                                                                            */
/*                                                                            */
/******************************************************************************/
static int
ip2_write( PTTY tty, int user, const unsigned char *pData, int count)
{
	i2ChanStrPtr  pCh = tty->driver_data;
	int bytesSent = 0;
	unsigned long flags;

#ifdef IP2DEBUG_TRACE
   ip2trace (CHANN, ITRC_WRITE, ITRC_ENTER, 2, count, -1 );
#endif

	/* Flush out any buffered data left over from ip2_putchar() calls. */
	ip2_flush_chars( tty );

	/* This is the actual move bit. Make sure it does what we need!!!!! */
	WRITE_LOCK_IRQSAVE(&pCh->Pbuf_spinlock,flags);
	bytesSent = i2Output( pCh, pData, count, user );
	WRITE_UNLOCK_IRQRESTORE(&pCh->Pbuf_spinlock,flags);

#ifdef IP2DEBUG_TRACE
   ip2trace (CHANN, ITRC_WRITE, ITRC_RETURN, 1, bytesSent );
#endif
	return bytesSent > 0 ? bytesSent : 0;
}

/******************************************************************************/
/* Function:   ip2_putchar()                                                  */
/* Parameters: Pointer to tty structure                                       */
/*             Character to write                                             */
/* Returns:    Nothing                                                        */
/*                                                                            */
/* Description:                                                               */
/*                                                                            */
/*                                                                            */
/******************************************************************************/
static void
ip2_putchar( PTTY tty, unsigned char ch )
{
	i2ChanStrPtr  pCh = tty->driver_data;
	unsigned long flags;

#ifdef IP2DEBUG_TRACE
//	ip2trace (CHANN, ITRC_PUTC, ITRC_ENTER, 1, ch );
#endif

	WRITE_LOCK_IRQSAVE(&pCh->Pbuf_spinlock,flags);
	pCh->Pbuf[pCh->Pbuf_stuff++] = ch;
	if ( pCh->Pbuf_stuff == sizeof pCh->Pbuf ) {
		WRITE_UNLOCK_IRQRESTORE(&pCh->Pbuf_spinlock,flags);
		ip2_flush_chars( tty );
	} else
		WRITE_UNLOCK_IRQRESTORE(&pCh->Pbuf_spinlock,flags);

#ifdef IP2DEBUG_TRACE
//	ip2trace (CHANN, ITRC_PUTC, ITRC_RETURN, 1, ch );
#endif
}

/******************************************************************************/
/* Function:   ip2_flush_chars()                                              */
/* Parameters: Pointer to tty structure                                       */
/* Returns:    Nothing                                                        */
/*                                                                            */
/* Description:                                                               */
/*                                                                            */
/******************************************************************************/
static void
ip2_flush_chars( PTTY tty )
{
	int   strip;
	i2ChanStrPtr  pCh = tty->driver_data;
	unsigned long flags;

	WRITE_LOCK_IRQSAVE(&pCh->Pbuf_spinlock,flags);
	if ( pCh->Pbuf_stuff ) {
#ifdef IP2DEBUG_TRACE
//	ip2trace (CHANN, ITRC_PUTC, 10, 1, strip );
#endif
		//
		// We may need to restart i2Output if it does not fullfill this request
		//
		strip = i2Output( pCh, pCh->Pbuf, pCh->Pbuf_stuff, 0 );
		if ( strip != pCh->Pbuf_stuff ) {
			memmove( pCh->Pbuf, &pCh->Pbuf[strip], pCh->Pbuf_stuff - strip );
		}
		pCh->Pbuf_stuff -= strip;
	}
	WRITE_UNLOCK_IRQRESTORE(&pCh->Pbuf_spinlock,flags);
}

/******************************************************************************/
/* Function:   ip2_write_room()                                               */
/* Parameters: Pointer to tty structure                                       */
/* Returns:    Number of bytes that the driver can accept                     */
/*                                                                            */
/* Description:                                                               */
/*                                                                            */
/******************************************************************************/
static int
ip2_write_room ( PTTY tty )
{
	int bytesFree;
	i2ChanStrPtr  pCh = tty->driver_data;
	unsigned long flags;

	READ_LOCK_IRQSAVE(&pCh->Pbuf_spinlock,flags);
	bytesFree = i2OutputFree( pCh ) - pCh->Pbuf_stuff;
	READ_UNLOCK_IRQRESTORE(&pCh->Pbuf_spinlock,flags);

#ifdef IP2DEBUG_TRACE
	ip2trace (CHANN, ITRC_WRITE, 11, 1, bytesFree );
#endif

	return ((bytesFree > 0) ? bytesFree : 0);
}

/******************************************************************************/
/* Function:   ip2_chars_in_buf()                                             */
/* Parameters: Pointer to tty structure                                       */
/* Returns:    Number of bytes queued for transmission                        */
/*                                                                            */
/* Description:                                                               */
/*                                                                            */
/*                                                                            */
/******************************************************************************/
static int
ip2_chars_in_buf ( PTTY tty )
{
	i2ChanStrPtr  pCh = tty->driver_data;
	int rc;
	unsigned long flags;
#ifdef IP2DEBUG_TRACE
	ip2trace (CHANN, ITRC_WRITE, 12, 1, pCh->Obuf_char_count + pCh->Pbuf_stuff );
#endif
#ifdef IP2DEBUG_WRITE
	printk (KERN_DEBUG "IP2: chars in buffer = %d (%d,%d)\n",
				 pCh->Obuf_char_count + pCh->Pbuf_stuff,
				 pCh->Obuf_char_count, pCh->Pbuf_stuff );
#endif
	READ_LOCK_IRQSAVE(&pCh->Obuf_spinlock,flags);
	rc =  pCh->Obuf_char_count;
	READ_UNLOCK_IRQRESTORE(&pCh->Obuf_spinlock,flags);
	READ_LOCK_IRQSAVE(&pCh->Pbuf_spinlock,flags);
	rc +=  pCh->Pbuf_stuff;
	READ_UNLOCK_IRQRESTORE(&pCh->Pbuf_spinlock,flags);
	return rc;
}

/******************************************************************************/
/* Function:   ip2_flush_buffer()                                             */
/* Parameters: Pointer to tty structure                                       */
/* Returns:    Nothing                                                        */
/*                                                                            */
/* Description:                                                               */
/*                                                                            */
/*                                                                            */
/******************************************************************************/
static void
ip2_flush_buffer( PTTY tty )
{
	i2ChanStrPtr  pCh = tty->driver_data;
	unsigned long flags;

#ifdef IP2DEBUG_TRACE
	ip2trace (CHANN, ITRC_FLUSH, ITRC_ENTER, 0 );
#endif
#ifdef IP2DEBUG_WRITE
	printk (KERN_DEBUG "IP2: flush buffer\n" );
#endif
	WRITE_LOCK_IRQSAVE(&pCh->Pbuf_spinlock,flags);
	pCh->Pbuf_stuff = 0;
	WRITE_U