i2lib.c

linux-2.6.15.6

	set_current_state( TASK_INTERRUPTIBLE );

	serviceOutgoingFifo( pB );
	
	schedule();	// Now we take our interruptible sleep on

	// Clean up the queue
	set_current_state( TASK_RUNNING );
	remove_wait_queue(&(pCh->pBookmarkWait), &wait);

	// if expires == 0 then timer poped, then do not need to del_timer
	if ((timeout > 0) && pCh->BookmarkTimer.expires && 
	                     time_before(jiffies, pCh->BookmarkTimer.expires)) {
		del_timer( &(pCh->BookmarkTimer) );
		pCh->BookmarkTimer.expires = 0;

		ip2trace (CHANN, ITRC_DRAIN, 3, 1, pCh->BookmarkTimer.expires );

	}
	ip2trace (CHANN, ITRC_DRAIN, ITRC_RETURN, 1, pCh->BookmarkTimer.expires );
	return;
}

//******************************************************************************
// Function:   i2OutputFree(pCh)
// Parameters: Pointer to a channel structure
// Returns:    Space in output buffer
//
// Description:
// Returns -1 if very gross error. Otherwise returns the amount of bytes still
// free in the output buffer.
//******************************************************************************
static int
i2OutputFree(i2ChanStrPtr pCh)
{
	int amountToMove;
	unsigned long flags;

	// Ensure channel structure seems real
	if ( !i2Validate ( pCh ) ) {
		return -1;
	}
	READ_LOCK_IRQSAVE(&pCh->Obuf_spinlock,flags);
	amountToMove = pCh->Obuf_strip - pCh->Obuf_stuff - 1;
	READ_UNLOCK_IRQRESTORE(&pCh->Obuf_spinlock,flags);

	if (amountToMove < 0) {
		amountToMove += OBUF_SIZE;
	}
	// If this is negative, we will discover later
	amountToMove -= sizeof(i2DataHeader);

	return (amountToMove < 0) ? 0 : amountToMove;
}
static void

ip2_owake( PTTY tp)
{
	i2ChanStrPtr  pCh;

	if (tp == NULL) return;

	pCh = tp->driver_data;

	ip2trace (CHANN, ITRC_SICMD, 10, 2, tp->flags,
			(1 << TTY_DO_WRITE_WAKEUP) );

	wake_up_interruptible ( &tp->write_wait );
	if ( ( tp->flags & (1 << TTY_DO_WRITE_WAKEUP) ) 
	  && tp->ldisc.write_wakeup )
	{
		(tp->ldisc.write_wakeup) ( tp );

		ip2trace (CHANN, ITRC_SICMD, 11, 0 );

	}
}

static inline void
set_baud_params(i2eBordStrPtr pB) 
{
	int i,j;
	i2ChanStrPtr  *pCh;

	pCh = (i2ChanStrPtr *) pB->i2eChannelPtr;

	for (i = 0; i < ABS_MAX_BOXES; i++) {
		if (pB->channelBtypes.bid_value[i]) {
			if (BID_HAS_654(pB->channelBtypes.bid_value[i])) {
				for (j = 0; j < ABS_BIGGEST_BOX; j++) {
					if (pCh[i*16+j] == NULL)
						break;
					(pCh[i*16+j])->BaudBase    = 921600;	// MAX for ST654
					(pCh[i*16+j])->BaudDivisor = 96;
				}
			} else {	// has cirrus cd1400
				for (j = 0; j < ABS_BIGGEST_BOX; j++) {
					if (pCh[i*16+j] == NULL)
						break;
					(pCh[i*16+j])->BaudBase    = 115200;	// MAX for CD1400
					(pCh[i*16+j])->BaudDivisor = 12;
				}
			}
		}
	}
}

//******************************************************************************
// Function:   i2StripFifo(pB)
// Parameters: Pointer to a board structure
// Returns:    ?
//
// Description:
// Strips all the available data from the incoming FIFO, identifies the type of
// packet, and either buffers the data or does what needs to be done.
//
// Note there is no overflow checking here: if the board sends more data than it
// ought to, we will not detect it here, but blindly overflow...
//******************************************************************************

// A buffer for reading in blocks for unknown channels
static unsigned char junkBuffer[IBUF_SIZE];

// A buffer to read in a status packet. Because of the size of the count field
// for these things, the maximum packet size must be less than MAX_CMD_PACK_SIZE
static unsigned char cmdBuffer[MAX_CMD_PACK_SIZE + 4];

// This table changes the bit order from MSR order given by STAT_MODEM packet to
// status bits used in our library.
static char xlatDss[16] = {
0      | 0     | 0      | 0      ,
0      | 0     | 0      | I2_CTS ,
0      | 0     | I2_DSR | 0      ,
0      | 0     | I2_DSR | I2_CTS ,
0      | I2_RI | 0      | 0      ,
0      | I2_RI | 0      | I2_CTS ,
0      | I2_RI | I2_DSR | 0      ,
0      | I2_RI | I2_DSR | I2_CTS ,
I2_DCD | 0     | 0      | 0      ,
I2_DCD | 0     | 0      | I2_CTS ,
I2_DCD | 0     | I2_DSR | 0      ,
I2_DCD | 0     | I2_DSR | I2_CTS ,
I2_DCD | I2_RI | 0      | 0      ,
I2_DCD | I2_RI | 0      | I2_CTS ,
I2_DCD | I2_RI | I2_DSR | 0      ,
I2_DCD | I2_RI | I2_DSR | I2_CTS };

static inline void
i2StripFifo(i2eBordStrPtr pB)
{
	i2ChanStrPtr pCh;
	int channel;
	int count;
	unsigned short stuffIndex;
	int amountToRead;
	unsigned char *pc, *pcLimit;
	unsigned char uc;
	unsigned char dss_change;
	unsigned long bflags,cflags;

//	ip2trace (ITRC_NO_PORT, ITRC_SFIFO, ITRC_ENTER, 0 );

	while (HAS_INPUT(pB)) {
//		ip2trace (ITRC_NO_PORT, ITRC_SFIFO, 2, 0 );

		// Process packet from fifo a one atomic unit
		WRITE_LOCK_IRQSAVE(&pB->read_fifo_spinlock,bflags);
   
		// The first word (or two bytes) will have channel number and type of
		// packet, possibly other information
		pB->i2eLeadoffWord[0] = iiReadWord(pB);

		switch(PTYPE_OF(pB->i2eLeadoffWord))
		{
		case PTYPE_DATA:
			pB->got_input = 1;

//			ip2trace (ITRC_NO_PORT, ITRC_SFIFO, 3, 0 );

			channel = CHANNEL_OF(pB->i2eLeadoffWord); /* Store channel */
			count = iiReadWord(pB);          /* Count is in the next word */

// NEW: Check the count for sanity! Should the hardware fail, our death
// is more pleasant. While an oversize channel is acceptable (just more
// than the driver supports), an over-length count clearly means we are
// sick!
			if ( ((unsigned int)count) > IBUF_SIZE ) {
				pB->i2eFatal = 2;
				WRITE_UNLOCK_IRQRESTORE(&pB->read_fifo_spinlock,bflags);
				return;     /* Bail out ASAP */
			}
			// Channel is illegally big ?
			if ((channel >= pB->i2eChannelCnt) ||
				(NULL==(pCh = ((i2ChanStrPtr*)pB->i2eChannelPtr)[channel])))
			{
				iiReadBuf(pB, junkBuffer, count);
				WRITE_UNLOCK_IRQRESTORE(&pB->read_fifo_spinlock,bflags);
				break;         /* From switch: ready for next packet */
			}

			// Channel should be valid, then

			// If this is a hot-key, merely post its receipt for now. These are
			// always supposed to be 1-byte packets, so we won't even check the
			// count. Also we will post an acknowledgement to the board so that
			// more data can be forthcoming. Note that we are not trying to use
			// these sequences in this driver, merely to robustly ignore them.
			if(ID_OF(pB->i2eLeadoffWord) == ID_HOT_KEY)
			{
				pCh->hotKeyIn = iiReadWord(pB) & 0xff;
				WRITE_UNLOCK_IRQRESTORE(&pB->read_fifo_spinlock,bflags);
				i2QueueCommands(PTYPE_BYPASS, pCh, 0, 1, CMD_HOTACK);
				break;   /* From the switch: ready for next packet */
			}

			// Normal data! We crudely assume there is room for the data in our
			// buffer because the board wouldn't have exceeded his credit limit.
			WRITE_LOCK_IRQSAVE(&pCh->Ibuf_spinlock,cflags);
													// We have 2 locks now
			stuffIndex = pCh->Ibuf_stuff;
			amountToRead = IBUF_SIZE - stuffIndex;
			if (amountToRead > count)
				amountToRead = count;

			// stuffIndex would have been already adjusted so there would 
			// always be room for at least one, and count is always at least
			// one.

			iiReadBuf(pB, &(pCh->Ibuf[stuffIndex]), amountToRead);
			pCh->icount.rx += amountToRead;

			// Update the stuffIndex by the amount of data moved. Note we could
			// never ask for more data than would just fit. However, we might
			// have read in one more byte than we wanted because the read
			// rounds up to even bytes. If this byte is on the end of the
			// packet, and is padding, we ignore it. If the byte is part of
			// the actual data, we need to move it.

			stuffIndex += amountToRead;

			if (stuffIndex >= IBUF_SIZE) {
				if ((amountToRead & 1) && (count > amountToRead)) {
					pCh->Ibuf[0] = pCh->Ibuf[IBUF_SIZE];
					amountToRead++;
					stuffIndex = 1;
				} else {
					stuffIndex = 0;
				}
			}

			// If there is anything left over, read it as well
			if (count > amountToRead) {
				amountToRead = count - amountToRead;
				iiReadBuf(pB, &(pCh->Ibuf[stuffIndex]), amountToRead);
				pCh->icount.rx += amountToRead;
				stuffIndex += amountToRead;
			}

			// Update stuff index
			pCh->Ibuf_stuff = stuffIndex;
			WRITE_UNLOCK_IRQRESTORE(&pCh->Ibuf_spinlock,cflags);
			WRITE_UNLOCK_IRQRESTORE(&pB->read_fifo_spinlock,bflags);

#ifdef USE_IQ
			schedule_work(&pCh->tqueue_input);
#else
			do_input(pCh);
#endif

			// Note we do not need to maintain any flow-control credits at this
			// time:  if we were to increment .asof and decrement .room, there
			// would be no net effect. Instead, when we strip data, we will
			// increment .asof and leave .room unchanged.

			break;   // From switch: ready for next packet

		case PTYPE_STATUS:
			ip2trace (ITRC_NO_PORT, ITRC_SFIFO, 4, 0 );
      
			count = CMD_COUNT_OF(pB->i2eLeadoffWord);

			iiReadBuf(pB, cmdBuffer, count);
			// We can release early with buffer grab
			WRITE_UNLOCK_IRQRESTORE(&pB->read_fifo_spinlock,bflags);

			pc = cmdBuffer;
			pcLimit = &(cmdBuffer[count]);

			while (pc < pcLimit) {
				channel = *pc++;

				ip2trace (channel, ITRC_SFIFO, 7, 2, channel, *pc );

				/* check for valid channel */
				if (channel < pB->i2eChannelCnt
					 && 
					 (pCh = (((i2ChanStrPtr*)pB->i2eChannelPtr)[channel])) != NULL
					)
				{
					dss_change = 0;

					switch (uc = *pc++)
					{
					/* Breaks and modem signals are easy: just update status */
					case STAT_CTS_UP:
						if ( !(pCh->dataSetIn & I2_CTS) )
						{
							pCh->dataSetIn |= I2_DCTS;
							pCh->icount.cts++;
							dss_change = 1;
						}
						pCh->dataSetIn |= I2_CTS;
						break;

					case STAT_CTS_DN:
						if ( pCh->dataSetIn & I2_CTS )
						{
							pCh->dataSetIn |= I2_DCTS;
							pCh->icount.cts++;
							dss_change = 1;
						}
						pCh->dataSetIn &= ~I2_CTS;
						break;

					case STAT_DCD_UP:
						ip2trace (channel, ITRC_MODEM, 1, 1, pCh->dataSetIn );

						if ( !(pCh->dataSetIn & I2_DCD) )
						{
							ip2trace (CHANN, ITRC_MODEM, 2, 0 );
							pCh->dataSetIn |= I2_DDCD;
							pCh->icount.dcd++;
							dss_change = 1;
						}
						pCh->dataSetIn |= I2_DCD;

						ip2trace (channel, ITRC_MODEM, 3, 1, pCh->dataSetIn );
						break;

					case STAT_DCD_DN:
						ip2trace (channel, ITRC_MODEM, 4, 1, pCh->dataSetIn );
						if ( pCh->dataSetIn & I2_DCD )
						{
							ip2trace (channel, ITRC_MODEM, 5, 0 );
							pCh->dataSetIn |= I2_DDCD;
							pCh->icount.dcd++;
							dss_change = 1;
						}
						pCh->dataSetIn &= ~I2_DCD;

						ip2trace (channel, ITRC_MODEM, 6, 1, pCh->dataSetIn );
						break;

					case STAT_DSR_UP:
						if ( !(pCh->dataSetIn & I2_DSR) )
						{
							pCh->dataSetIn |= I2_DDSR;
							pCh->icount.dsr++;
							dss_change = 1;
						}
						pCh->dataSetIn |= I2_DSR;
						break;

					case STAT_DSR_DN:
						if ( pCh->dataSetIn & I2_DSR )
						{
							pCh->dataSetIn |= I2_DDSR;
							pCh->icount.dsr++;
							dss_change = 1;
						}
						pCh->dataSetIn &= ~I2_DSR;
						break;

					case STAT_RI_UP:
						if ( !(pCh->dataSetIn & I2_RI) )
						{
							pCh->dataSetIn |= I2_DRI;
							pCh->icount.rng++;
							dss_change = 1;
						}
						pCh->dataSetIn |= I2_RI ;
						break;

					case STAT_RI_DN:
						// to be compat with serial.c
						//if ( pCh->dataSetIn & I2_RI )
						//{
						//	pCh->dataSetIn |= I2_DRI;
						//	pCh->icount.rng++; 
						//	dss_change = 1;
						//}
						pCh->dataSetIn &= ~I2_RI ;
						break;

					case STAT_BRK_DET:
						pCh->dataSetIn |= I2_BRK;
						pCh->icount.brk++;
						dss_change = 1;
						break;

					// Bookmarks? one less request we're waiting for
					case STAT_BMARK:
						pCh->bookMarks--;
						if (pCh->bookMarks <= 0 ) {
							pCh->bookMarks = 0;
							wake_up_interruptible( &pCh->pBookmarkWait );

						ip2trace (channel, ITRC_DRAIN, 20, 1, pCh->BookmarkTimer.expires );
						}
						break;

					// Flow control packets? Update the new credits, and if
					// someone was waiting for output, queue him up again.
					case STAT_FLOW:
						pCh->outfl.room =
							((flowStatPtr)pc)->room -
							(pCh->outfl.asof - ((flowStatPtr)pc)->asof);

						ip2trace (channel, ITRC_STFLW, 1, 1, pCh->outfl.room );

						if (pCh->channelNeeds & NEED_CREDIT)
						{
							ip2trace (channel, ITRC_STFLW, 2, 1, pCh->channelNeeds);

							pCh->channelNeeds &= ~NEED_CREDIT;
							i2QueueNeeds(pB, pCh, NEED_INLINE);
							if ( pCh->pTTY )
								ip2_owake(pCh->pTTY);
						}

						ip2trace (channel, ITRC_STFLW, 3, 1, pCh->channelNeeds);

						pc += sizeof(flowStat);
						break;

					/* Special packets: */
					/* Just copy the information into the channel structure */