Linux-2.6.33.2/drivers/char/ip2/i2lib.c
/*******************************************************************************
*
* (c) 1999 by Computone Corporation
*
********************************************************************************
*
*
* PACKAGE: Linux tty Device Driver for IntelliPort family of multiport
* serial I/O controllers.
*
* DESCRIPTION: High-level interface code for the device driver. Uses the
* Extremely Low Level Interface Support (i2ellis.c). Provides an
* interface to the standard loadware, to support drivers or
* application code. (This is included source code, not a separate
* compilation module.)
*
*******************************************************************************/
//------------------------------------------------------------------------------
// Note on Strategy:
// Once the board has been initialized, it will interrupt us when:
// 1) It has something in the fifo for us to read (incoming data, flow control
// packets, or whatever).
// 2) It has stripped whatever we have sent last time in the FIFO (and
// consequently is ready for more).
//
// Note also that the buffer sizes declared in i2lib.h are VERY SMALL. This
// worsens performance considerably, but is done so that a great many channels
// might use only a little memory.
//------------------------------------------------------------------------------
//------------------------------------------------------------------------------
// Revision History:
//
// 0.00 - 4/16/91 --- First Draft
// 0.01 - 4/29/91 --- 1st beta release
// 0.02 - 6/14/91 --- Changes to allow small model compilation
// 0.03 - 6/17/91 MAG Break reporting protected from interrupts routines with
// in-line asm added for moving data to/from ring buffers,
// replacing a variety of methods used previously.
// 0.04 - 6/21/91 MAG Initial flow-control packets not queued until
// i2_enable_interrupts time. Former versions would enqueue
// them at i2_init_channel time, before we knew how many
// channels were supposed to exist!
// 0.05 - 10/12/91 MAG Major changes: works through the ellis.c routines now;
// supports new 16-bit protocol and expandable boards.
// - 10/24/91 MAG Most changes in place and stable.
// 0.06 - 2/20/92 MAG Format of CMD_HOTACK corrected: the command takes no
// argument.
// 0.07 -- 3/11/92 MAG Support added to store special packet types at interrupt
// level (mostly responses to specific commands.)
// 0.08 -- 3/30/92 MAG Support added for STAT_MODEM packet
// 0.09 -- 6/24/93 MAG i2Link... needed to update number of boards BEFORE
// turning on the interrupt.
// 0.10 -- 6/25/93 MAG To avoid gruesome death from a bad board, we sanity check
// some incoming.
//
// 1.1 - 12/25/96 AKM Linux version.
// - 10/09/98 DMC Revised Linux version.
//------------------------------------------------------------------------------
//************
//* Includes *
//************
#include <linux/sched.h>
#include "i2lib.h"
//***********************
//* Function Prototypes *
//***********************
static void i2QueueNeeds(i2eBordStrPtr, i2ChanStrPtr, int);
static i2ChanStrPtr i2DeQueueNeeds(i2eBordStrPtr, int );
static void i2StripFifo(i2eBordStrPtr);
static void i2StuffFifoBypass(i2eBordStrPtr);
static void i2StuffFifoFlow(i2eBordStrPtr);
static void i2StuffFifoInline(i2eBordStrPtr);
static int i2RetryFlushOutput(i2ChanStrPtr);
// Not a documented part of the library routines (careful...) but the Diagnostic
// i2diag.c finds them useful to help the throughput in certain limited
// single-threaded operations.
static void iiSendPendingMail(i2eBordStrPtr);
static void serviceOutgoingFifo(i2eBordStrPtr);
// Functions defined in ip2.c as part of interrupt handling
static void do_input(struct work_struct *);
static void do_status(struct work_struct *);
//***************
//* Debug Data *
//***************
#ifdef DEBUG_FIFO
unsigned char DBGBuf[0x4000];
unsigned short I = 0;
static void
WriteDBGBuf(char *s, unsigned char *src, unsigned short n )
{
char *p = src;
// XXX: We need a spin lock here if we ever use this again
while (*s) { // copy label
DBGBuf[I] = *s++;
I = I++ & 0x3fff;
}
while (n--) { // copy data
DBGBuf[I] = *p++;
I = I++ & 0x3fff;
}
}
static void
fatality(i2eBordStrPtr pB )
{
int i;
for (i=0;i<sizeof(DBGBuf);i++) {
if ((i%16) == 0)
printk("\n%4x:",i);
printk("%02x ",DBGBuf[i]);
}
printk("\n");
for (i=0;i<sizeof(DBGBuf);i++) {
if ((i%16) == 0)
printk("\n%4x:",i);
if (DBGBuf[i] >= ' ' && DBGBuf[i] <= '~') {
printk(" %c ",DBGBuf[i]);
} else {
printk(" . ");
}
}
printk("\n");
printk("Last index %x\n",I);
}
#endif /* DEBUG_FIFO */
//********
//* Code *
//********
static inline int
i2Validate ( i2ChanStrPtr pCh )
{
//ip2trace(pCh->port_index, ITRC_VERIFY,ITRC_ENTER,2,pCh->validity,
// (CHANNEL_MAGIC | CHANNEL_SUPPORT));
return ((pCh->validity & (CHANNEL_MAGIC_BITS | CHANNEL_SUPPORT))
== (CHANNEL_MAGIC | CHANNEL_SUPPORT));
}
static void iiSendPendingMail_t(unsigned long data)
{
i2eBordStrPtr pB = (i2eBordStrPtr)data;
iiSendPendingMail(pB);
}
//******************************************************************************
// Function: iiSendPendingMail(pB)
// Parameters: Pointer to a board structure
// Returns: Nothing
//
// Description:
// If any outgoing mail bits are set and there is outgoing mailbox is empty,
// send the mail and clear the bits.
//******************************************************************************
static void
iiSendPendingMail(i2eBordStrPtr pB)
{
if (pB->i2eOutMailWaiting && (!pB->i2eWaitingForEmptyFifo) )
{
if (iiTrySendMail(pB, pB->i2eOutMailWaiting))
{
/* If we were already waiting for fifo to empty,
* or just sent MB_OUT_STUFFED, then we are
* still waiting for it to empty, until we should
* receive an MB_IN_STRIPPED from the board.
*/
pB->i2eWaitingForEmptyFifo |=
(pB->i2eOutMailWaiting & MB_OUT_STUFFED);
pB->i2eOutMailWaiting = 0;
pB->SendPendingRetry = 0;
} else {
/* The only time we hit this area is when "iiTrySendMail" has
failed. That only occurs when the outbound mailbox is
still busy with the last message. We take a short breather
to let the board catch up with itself and then try again.
16 Retries is the limit - then we got a borked board.
/\/\|=mhw=|\/\/ */
if( ++pB->SendPendingRetry < 16 ) {
setup_timer(&pB->SendPendingTimer,
iiSendPendingMail_t, (unsigned long)pB);
mod_timer(&pB->SendPendingTimer, jiffies + 1);
} else {
printk( KERN_ERR "IP2: iiSendPendingMail unable to queue outbound mail\n" );
}
}
}
}
//******************************************************************************
// Function: i2InitChannels(pB, nChannels, pCh)
// Parameters: Pointer to Ellis Board structure
// Number of channels to initialize
// Pointer to first element in an array of channel structures
// Returns: Success or failure
//
// Description:
//
// This function patches pointers, back-pointers, and initializes all the
// elements in the channel structure array.
//
// This should be run after the board structure is initialized, through having
// loaded the standard loadware (otherwise it complains).
//
// In any case, it must be done before any serious work begins initializing the
// irq's or sending commands...
//
//******************************************************************************
static int
i2InitChannels ( i2eBordStrPtr pB, int nChannels, i2ChanStrPtr pCh)
{
int index, stuffIndex;
i2ChanStrPtr *ppCh;
if (pB->i2eValid != I2E_MAGIC) {
I2_COMPLETE(pB, I2EE_BADMAGIC);
}
if (pB->i2eState != II_STATE_STDLOADED) {
I2_COMPLETE(pB, I2EE_BADSTATE);
}
rwlock_init(&pB->read_fifo_spinlock);
rwlock_init(&pB->write_fifo_spinlock);
rwlock_init(&pB->Dbuf_spinlock);
rwlock_init(&pB->Bbuf_spinlock);
rwlock_init(&pB->Fbuf_spinlock);
// NO LOCK needed yet - this is init
pB->i2eChannelPtr = pCh;
pB->i2eChannelCnt = nChannels;
pB->i2Fbuf_strip = pB->i2Fbuf_stuff = 0;
pB->i2Dbuf_strip = pB->i2Dbuf_stuff = 0;
pB->i2Bbuf_strip = pB->i2Bbuf_stuff = 0;
pB->SendPendingRetry = 0;
memset ( pCh, 0, sizeof (i2ChanStr) * nChannels );
for (index = stuffIndex = 0, ppCh = (i2ChanStrPtr *)(pB->i2Fbuf);
nChannels && index < ABS_MOST_PORTS;
index++)
{
if ( !(pB->i2eChannelMap[index >> 4] & (1 << (index & 0xf)) ) ) {
continue;
}
rwlock_init(&pCh->Ibuf_spinlock);
rwlock_init(&pCh->Obuf_spinlock);
rwlock_init(&pCh->Cbuf_spinlock);
rwlock_init(&pCh->Pbuf_spinlock);
// NO LOCK needed yet - this is init
// Set up validity flag according to support level
if (pB->i2eGoodMap[index >> 4] & (1 << (index & 0xf)) ) {
pCh->validity = CHANNEL_MAGIC | CHANNEL_SUPPORT;
} else {
pCh->validity = CHANNEL_MAGIC;
}
pCh->pMyBord = pB; /* Back-pointer */
// Prepare an outgoing flow-control packet to send as soon as the chance
// occurs.
if ( pCh->validity & CHANNEL_SUPPORT ) {
pCh->infl.hd.i2sChannel = index;
pCh->infl.hd.i2sCount = 5;
pCh->infl.hd.i2sType = PTYPE_BYPASS;
pCh->infl.fcmd = 37;
pCh->infl.asof = 0;
pCh->infl.room = IBUF_SIZE - 1;
pCh->whenSendFlow = (IBUF_SIZE/5)*4; // when 80% full
// The following is similar to calling i2QueueNeeds, except that this
// is done in longhand, since we are setting up initial conditions on
// many channels at once.
pCh->channelNeeds = NEED_FLOW; // Since starting from scratch
pCh->sinceLastFlow = 0; // No bytes received since last flow
// control packet was queued
stuffIndex++;
*ppCh++ = pCh; // List this channel as needing
// initial flow control packet sent
}
// Don't allow anything to be sent until the status packets come in from
// the board.
pCh->outfl.asof = 0;
pCh->outfl.room = 0;
// Initialize all the ring buffers
pCh->Ibuf_stuff = pCh->Ibuf_strip = 0;
pCh->Obuf_stuff = pCh->Obuf_strip = 0;
pCh->Cbuf_stuff = pCh->Cbuf_strip = 0;
memset( &pCh->icount, 0, sizeof (struct async_icount) );
pCh->hotKeyIn = HOT_CLEAR;
pCh->channelOptions = 0;
pCh->bookMarks = 0;
init_waitqueue_head(&pCh->pBookmarkWait);
init_waitqueue_head(&pCh->open_wait);
init_waitqueue_head(&pCh->close_wait);
init_waitqueue_head(&pCh->delta_msr_wait);
// Set base and divisor so default custom rate is 9600
pCh->BaudBase = 921600; // MAX for ST654, changed after we get
pCh->BaudDivisor = 96; // the boxids (UART types) later
pCh->dataSetIn = 0;
pCh->dataSetOut = 0;
pCh->wopen = 0;
pCh->throttled = 0;
pCh->speed = CBR_9600;
pCh->flags = 0;
pCh->ClosingDelay = 5*HZ/10;
pCh->ClosingWaitTime = 30*HZ;
// Initialize task queue objects
INIT_WORK(&pCh->tqueue_input, do_input);
INIT_WORK(&pCh->tqueue_status, do_status);
#ifdef IP2DEBUG_TRACE
pCh->trace = ip2trace;
#endif
++pCh;
--nChannels;
}
// No need to check for wrap here; this is initialization.
pB->i2Fbuf_stuff = stuffIndex;
I2_COMPLETE(pB, I2EE_GOOD);
}
//******************************************************************************
// Function: i2DeQueueNeeds(pB, type)
// Parameters: Pointer to a board structure
// type bit map: may include NEED_INLINE, NEED_BYPASS, or NEED_FLOW
// Returns:
// Pointer to a channel structure
//
// Description: Returns pointer struct of next channel that needs service of
// the type specified. Otherwise returns a NULL reference.
//
//******************************************************************************
static i2ChanStrPtr
i2DeQueueNeeds(i2eBordStrPtr pB, int type)
{
unsigned short queueIndex;
unsigned long flags;
i2ChanStrPtr pCh = NULL;
switch(type) {
case NEED_INLINE:
write_lock_irqsave(&pB->Dbuf_spinlock, flags);
if ( pB->i2Dbuf_stuff != pB->i2Dbuf_strip)
{
queueIndex = pB->i2Dbuf_strip;
pCh = pB->i2Dbuf[queueIndex];
queueIndex++;
if (queueIndex >= CH_QUEUE_SIZE) {
queueIndex = 0;
}
pB->i2Dbuf_strip = queueIndex;
pCh->channelNeeds &= ~NEED_INLINE;
}
write_unlock_irqrestore(&pB->Dbuf_spinlock, flags);
break;
case NEED_BYPASS:
write_lock_irqsave(&pB->Bbuf_spinlock, flags);
if (pB->i2Bbuf_stuff != pB->i2Bbuf_strip)
{
queueIndex = pB->i2Bbuf_strip;
pCh = pB->i2Bbuf[queueIndex];
queueIndex++;
if (queueIndex >= CH_QUEUE_SIZE) {
queueIndex = 0;
}
pB->i2Bbuf_strip = queueIndex;
pCh->channelNeeds &= ~NEED_BYPASS;
}
write_unlock_irqrestore(&pB->Bbuf_spinlock, flags);
break;
case NEED_FLOW:
write_lock_irqsave(&pB->Fbuf_spinlock, flags);
if (pB->i2Fbuf_stuff != pB->i2Fbuf_strip)
{
queueIndex = pB->i2Fbuf_strip;
pCh = pB->i2Fbuf[queueIndex];
queueIndex++;
if (queueIndex >= CH_QUEUE_SIZE) {
queueIndex = 0;
}
pB->i2Fbuf_strip = queueIndex;
pCh->channelNeeds &= ~NEED_FLOW;
}
write_unlock_irqrestore(&pB->Fbuf_spinlock, flags);
break;
default:
printk(KERN_ERR "i2DeQueueNeeds called with bad type:%x\n",type);
break;
}
return pCh;
}
//******************************************************************************
// Function: i2QueueNeeds(pB, pCh, type)
// Parameters: Pointer to a board structure
// Pointer to a channel structure
// type bit map: may include NEED_INLINE, NEED_BYPASS, or NEED_FLOW
// Returns: Nothing
//
// Description:
// For each type of need selected, if the given channel is not already in the
// queue, adds it, and sets the flag indicating it is in the queue.
//******************************************************************************
static void
i2QueueNeeds(i2eBordStrPtr pB, i2ChanStrPtr pCh, int type)
{
unsigned short queueIndex;
unsigned long flags;
// We turn off all the interrupts during this brief process, since the
// interrupt-level code might want to put things on the queue as well.
switch (type) {
case NEED_INLINE:
write_lock_irqsave(&pB->Dbuf_spinlock, flags);
if ( !(pCh->channelNeeds & NEED_INLINE) )
{
pCh->channelNeeds |= NEED_INLINE;
queueIndex = pB->i2Dbuf_stuff;
pB->i2Dbuf[queueIndex++] = pCh;
if (queueIndex >= CH_QUEUE_SIZE)
queueIndex = 0;
pB->i2Dbuf_stuff = queueIndex;
}
write_unlock_irqrestore(&pB->Dbuf_spinlock, flags);
break;
case NEED_BYPASS:
write_lock_irqsave(&pB->Bbuf_spinlock, flags);
if ((type & NEED_BYPASS) && !(pCh->channelNeeds & NEED_BYPASS))
{
pCh->channelNeeds |= NEED_BYPASS;
queueIndex = pB->i2Bbuf_stuff;
pB->i2Bbuf[queueIndex++] = pCh;
if (queueIndex >= CH_QUEUE_SIZE)
queueIndex = 0;
pB->i2Bbuf_stuff = queueIndex;
}
write_unlock_irqrestore(&pB->Bbuf_spinlock, flags);
break;
case NEED_FLOW:
write_lock_irqsave(&pB->Fbuf_spinlock, flags);
if ((type & NEED_FLOW) && !(pCh->channelNeeds & NEED_FLOW))
{
pCh->channelNeeds |= NEED_FLOW;
queueIndex = pB->i2Fbuf_stuff;
pB->i2Fbuf[queueIndex++] = pCh;
if (queueIndex >= CH_QUEUE_SIZE)
queueIndex = 0;
pB->i2Fbuf_stuff = queueIndex;
}
write_unlock_irqrestore(&pB->Fbuf_spinlock, flags);
break;
case NEED_CREDIT:
pCh->channelNeeds |= NEED_CREDIT;
break;
default:
printk(KERN_ERR "i2QueueNeeds called with bad type:%x\n",type);
break;
}
return;
}
//******************************************************************************
// Function: i2QueueCommands(type, pCh, timeout, nCommands, pCs,...)
// Parameters: type - PTYPE_BYPASS or PTYPE_INLINE
// pointer to the channel structure
// maximum period to wait
// number of commands (n)
// n commands
// Returns: Number of commands sent, or -1 for error
//
// get board lock before calling
//
// Description:
// Queues up some commands to be sent to a channel. To send possibly several
// bypass or inline commands to the given channel. The timeout parameter
// indicates how many HUNDREDTHS OF SECONDS to wait until there is room:
// 0 = return immediately if no room, -ive = wait forever, +ive = number of
// 1/100 seconds to wait. Return values:
// -1 Some kind of nasty error: bad channel structure or invalid arguments.
// 0 No room to send all the commands
// (+) Number of commands sent
//******************************************************************************
static int
i2QueueCommands(int type, i2ChanStrPtr pCh, int timeout, int nCommands,
cmdSyntaxPtr pCs0,...)
{
int totalsize = 0;
int blocksize;
int lastended;
cmdSyntaxPtr *ppCs;
cmdSyntaxPtr pCs;
int count;
int flag;
i2eBordStrPtr pB;
unsigned short maxBlock;
unsigned short maxBuff;
short bufroom;
unsigned short stuffIndex;
unsigned char *pBuf;
unsigned char *pInsert;
unsigned char *pDest, *pSource;
unsigned short channel;
int cnt;
unsigned long flags = 0;
rwlock_t *lock_var_p = NULL;
// Make sure the channel exists, otherwise do nothing
if ( !i2Validate ( pCh ) ) {
return -1;
}
ip2trace (CHANN, ITRC_QUEUE, ITRC_ENTER, 0 );
pB = pCh->pMyBord;
// Board must also exist, and THE INTERRUPT COMMAND ALREADY SENT
if (pB->i2eValid != I2E_MAGIC || pB->i2eUsingIrq == I2_IRQ_UNDEFINED)
return -2;
// If the board has gone fatal, return bad, and also hit the trap routine if
// it exists.
if (pB->i2eFatal) {
if ( pB->i2eFatalTrap ) {
(*(pB)->i2eFatalTrap)(pB);
}
return -3;
}
// Set up some variables, Which buffers are we using? How big are they?
switch(type)
{
case PTYPE_INLINE:
flag = INL;
maxBlock = MAX_OBUF_BLOCK;
maxBuff = OBUF_SIZE;
pBuf = pCh->Obuf;
break;
case PTYPE_BYPASS:
flag = BYP;
maxBlock = MAX_CBUF_BLOCK;
maxBuff = CBUF_SIZE;
pBuf = pCh->Cbuf;
break;
default:
return -4;
}
// Determine the total size required for all the commands
totalsize = blocksize = sizeof(i2CmdHeader);
lastended = 0;
ppCs = &pCs0;
for ( count = nCommands; count; count--, ppCs++)
{
pCs = *ppCs;
cnt = pCs->length;
// Will a new block be needed for this one?
// Two possible reasons: too
// big or previous command has to be at the end of a packet.
if ((blocksize + cnt > maxBlock) || lastended) {
blocksize = sizeof(i2CmdHeader);
totalsize += sizeof(i2CmdHeader);
}
totalsize += cnt;
blocksize += cnt;
// If this command had to end a block, then we will make sure to
// account for it should there be any more blocks.
lastended = pCs->flags & END;
}
for (;;) {
// Make sure any pending flush commands go out before we add more data.
if ( !( pCh->flush_flags && i2RetryFlushOutput( pCh ) ) ) {
// How much room (this time through) ?
switch(type) {
case PTYPE_INLINE:
lock_var_p = &pCh->Obuf_spinlock;
write_lock_irqsave(lock_var_p, flags);
stuffIndex = pCh->Obuf_stuff;
bufroom = pCh->Obuf_strip - stuffIndex;
break;
case PTYPE_BYPASS:
lock_var_p = &pCh->Cbuf_spinlock;
write_lock_irqsave(lock_var_p, flags);
stuffIndex = pCh->Cbuf_stuff;
bufroom = pCh->Cbuf_strip - stuffIndex;
break;
default:
return -5;
}
if (--bufroom < 0) {
bufroom += maxBuff;
}
ip2trace (CHANN, ITRC_QUEUE, 2, 1, bufroom );
// Check for overflow
if (totalsize <= bufroom) {
// Normal Expected path - We still hold LOCK
break; /* from for()- Enough room: goto proceed */
}
ip2trace(CHANN, ITRC_QUEUE, 3, 1, totalsize);
write_unlock_irqrestore(lock_var_p, flags);
} else
ip2trace(CHANN, ITRC_QUEUE, 3, 1, totalsize);
/* Prepare to wait for buffers to empty */
serviceOutgoingFifo(pB); // Dump what we got
if (timeout == 0) {
return 0; // Tired of waiting
}
if (timeout > 0)
timeout--; // So negative values == forever
if (!in_interrupt()) {
schedule_timeout_interruptible(1); // short nap
} else {
// we cannot sched/sleep in interrupt silly
return 0;
}
if (signal_pending(current)) {
return 0; // Wake up! Time to die!!!
}
ip2trace (CHANN, ITRC_QUEUE, 4, 0 );
} // end of for(;;)
// At this point we have room and the lock - stick them in.
channel = pCh->infl.hd.i2sChannel;
pInsert = &pBuf[stuffIndex]; // Pointer to start of packet
pDest = CMD_OF(pInsert); // Pointer to start of command
// When we start counting, the block is the size of the header
for (blocksize = sizeof(i2CmdHeader), count = nCommands,
lastended = 0, ppCs = &pCs0;
count;
count--, ppCs++)
{
pCs = *ppCs; // Points to command protocol structure
// If this is a bookmark request command, post the fact that a bookmark
// request is pending. NOTE THIS TRICK ONLY WORKS BECAUSE CMD_BMARK_REQ
// has no parameters! The more general solution would be to reference
// pCs->cmd[0].
if (pCs == CMD_BMARK_REQ) {
pCh->bookMarks++;
ip2trace (CHANN, ITRC_DRAIN, 30, 1, pCh->bookMarks );
}
cnt = pCs->length;
// If this command would put us over the maximum block size or
// if the last command had to be at the end of a block, we end
// the existing block here and start a new one.
if ((blocksize + cnt > maxBlock) || lastended) {
ip2trace (CHANN, ITRC_QUEUE, 5, 0 );
PTYPE_OF(pInsert) = type;
CHANNEL_OF(pInsert) = channel;
// count here does not include the header
CMD_COUNT_OF(pInsert) = blocksize - sizeof(i2CmdHeader);
stuffIndex += blocksize;
if(stuffIndex >= maxBuff) {
stuffIndex = 0;
pInsert = pBuf;
}
pInsert = &pBuf[stuffIndex]; // Pointer to start of next pkt
pDest = CMD_OF(pInsert);
blocksize = sizeof(i2CmdHeader);
}
// Now we know there is room for this one in the current block
blocksize += cnt; // Total bytes in this command
pSource = pCs->cmd; // Copy the command into the buffer
while (cnt--) {
*pDest++ = *pSource++;
}
// If this command had to end a block, then we will make sure to account
// for it should there be any more blocks.
lastended = pCs->flags & END;
} // end for
// Clean up the final block by writing header, etc
PTYPE_OF(pInsert) = type;
CHANNEL_OF(pInsert) = channel;
// count here does not include the header
CMD_COUNT_OF(pInsert) = blocksize - sizeof(i2CmdHeader);
stuffIndex += blocksize;
if(stuffIndex >= maxBuff) {
stuffIndex = 0;
pInsert = pBuf;
}
// Updates the index, and post the need for service. When adding these to
// the queue of channels, we turn off the interrupt while doing so,
// because at interrupt level we might want to push a channel back to the
// end of the queue.
switch(type)
{
case PTYPE_INLINE:
pCh->Obuf_stuff = stuffIndex; // Store buffer pointer
write_unlock_irqrestore(&pCh->Obuf_spinlock, flags);
pB->debugInlineQueued++;
// Add the channel pointer to list of channels needing service (first
// come...), if it's not already there.
i2QueueNeeds(pB, pCh, NEED_INLINE);
break;
case PTYPE_BYPASS:
pCh->Cbuf_stuff = stuffIndex; // Store buffer pointer
write_unlock_irqrestore(&pCh->Cbuf_spinlock, flags);
pB->debugBypassQueued++;
// Add the channel pointer to list of channels needing service (first
// come...), if it's not already there.
i2QueueNeeds(pB, pCh, NEED_BYPASS);
break;
}
ip2trace (CHANN, ITRC_QUEUE, ITRC_RETURN, 1, nCommands );
return nCommands; // Good status: number of commands sent
}
//******************************************************************************
// Function: i2GetStatus(pCh,resetBits)
// Parameters: Pointer to a channel structure
// Bit map of status bits to clear
// Returns: Bit map of current status bits
//
// Description:
// Returns the state of data set signals, and whether a break has been received,
// (see i2lib.h for bit-mapped result). resetBits is a bit-map of any status
// bits to be cleared: I2_BRK, I2_PAR, I2_FRA, I2_OVR,... These are cleared
// AFTER the condition is passed. If pCh does not point to a valid channel,
// returns -1 (which would be impossible otherwise.
//******************************************************************************
static int
i2GetStatus(i2ChanStrPtr pCh, int resetBits)
{
unsigned short status;
i2eBordStrPtr pB;
ip2trace (CHANN, ITRC_STATUS, ITRC_ENTER, 2, pCh->dataSetIn, resetBits );
// Make sure the channel exists, otherwise do nothing */
if ( !i2Validate ( pCh ) )
return -1;
pB = pCh->pMyBord;
status = pCh->dataSetIn;
// Clear any specified error bits: but note that only actual error bits can
// be cleared, regardless of the value passed.
if (resetBits)
{
pCh->dataSetIn &= ~(resetBits & (I2_BRK | I2_PAR | I2_FRA | I2_OVR));
pCh->dataSetIn &= ~(I2_DDCD | I2_DCTS | I2_DDSR | I2_DRI);
}
ip2trace (CHANN, ITRC_STATUS, ITRC_RETURN, 1, pCh->dataSetIn );
return status;
}
//******************************************************************************
// Function: i2Input(pChpDest,count)
// Parameters: Pointer to a channel structure
// Pointer to data buffer
// Number of bytes to read
// Returns: Number of bytes read, or -1 for error
//
// Description:
// Strips data from the input buffer and writes it to pDest. If there is a
// collosal blunder, (invalid structure pointers or the like), returns -1.
// Otherwise, returns the number of bytes read.
//******************************************************************************
static int
i2Input(i2ChanStrPtr pCh)
{
int amountToMove;
unsigned short stripIndex;
int count;
unsigned long flags = 0;
ip2trace (CHANN, ITRC_INPUT, ITRC_ENTER, 0);
// Ensure channel structure seems real
if ( !i2Validate( pCh ) ) {
count = -1;
goto i2Input_exit;
}
write_lock_irqsave(&pCh->Ibuf_spinlock, flags);
// initialize some accelerators and private copies
stripIndex = pCh->Ibuf_strip;
count = pCh->Ibuf_stuff - stripIndex;
// If buffer is empty or requested data count was 0, (trivial case) return
// without any further thought.
if ( count == 0 ) {
write_unlock_irqrestore(&pCh->Ibuf_spinlock, flags);
goto i2Input_exit;
}
// Adjust for buffer wrap
if ( count < 0 ) {
count += IBUF_SIZE;
}
// Don't give more than can be taken by the line discipline
amountToMove = pCh->pTTY->receive_room;
if (count > amountToMove) {
count = amountToMove;
}
// How much could we copy without a wrap?
amountToMove = IBUF_SIZE - stripIndex;
if (amountToMove > count) {
amountToMove = count;
}
// Move the first block
pCh->pTTY->ldisc->ops->receive_buf( pCh->pTTY,
&(pCh->Ibuf[stripIndex]), NULL, amountToMove );
// If we needed to wrap, do the second data move
if (count > amountToMove) {
pCh->pTTY->ldisc->ops->receive_buf( pCh->pTTY,
pCh->Ibuf, NULL, count - amountToMove );
}
// Bump and wrap the stripIndex all at once by the amount of data read. This
// method is good regardless of whether the data was in one or two pieces.
stripIndex += count;
if (stripIndex >= IBUF_SIZE) {
stripIndex -= IBUF_SIZE;
}
pCh->Ibuf_strip = stripIndex;
// Update our flow control information and possibly queue ourselves to send
// it, depending on how much data has been stripped since the last time a
// packet was sent.
pCh->infl.asof += count;
if ((pCh->sinceLastFlow += count) >= pCh->whenSendFlow) {
pCh->sinceLastFlow -= pCh->whenSendFlow;
write_unlock_irqrestore(&pCh->Ibuf_spinlock, flags);
i2QueueNeeds(pCh->pMyBord, pCh, NEED_FLOW);
} else {
write_unlock_irqrestore(&pCh->Ibuf_spinlock, flags);
}
i2Input_exit:
ip2trace (CHANN, ITRC_INPUT, ITRC_RETURN, 1, count);
return count;
}
//******************************************************************************
// Function: i2InputFlush(pCh)
// Parameters: Pointer to a channel structure
// Returns: Number of bytes stripped, or -1 for error
//
// Description:
// Strips any data from the input buffer. If there is a collosal blunder,
// (invalid structure pointers or the like), returns -1. Otherwise, returns the
// number of bytes stripped.
//******************************************************************************
static int
i2InputFlush(i2ChanStrPtr pCh)
{
int count;
unsigned long flags;
// Ensure channel structure seems real
if ( !i2Validate ( pCh ) )
return -1;
ip2trace (CHANN, ITRC_INPUT, 10, 0);
write_lock_irqsave(&pCh->Ibuf_spinlock, flags);
count = pCh->Ibuf_stuff - pCh->Ibuf_strip;
// Adjust for buffer wrap
if (count < 0) {
count += IBUF_SIZE;
}
// Expedient way to zero out the buffer
pCh->Ibuf_strip = pCh->Ibuf_stuff;
// Update our flow control information and possibly queue ourselves to send
// it, depending on how much data has been stripped since the last time a
// packet was sent.
pCh->infl.asof += count;
if ( (pCh->sinceLastFlow += count) >= pCh->whenSendFlow )
{
pCh->sinceLastFlow -= pCh->whenSendFlow;
write_unlock_irqrestore(&pCh->Ibuf_spinlock, flags);
i2QueueNeeds(pCh->pMyBord, pCh, NEED_FLOW);
} else {
write_unlock_irqrestore(&pCh->Ibuf_spinlock, flags);
}
ip2trace (CHANN, ITRC_INPUT, 19, 1, count);
return count;
}
//******************************************************************************
// Function: i2InputAvailable(pCh)
// Parameters: Pointer to a channel structure
// Returns: Number of bytes available, or -1 for error
//
// Description:
// If there is a collosal blunder, (invalid structure pointers or the like),
// returns -1. Otherwise, returns the number of bytes stripped. Otherwise,
// returns the number of bytes available in the buffer.
//******************************************************************************
#if 0
static int
i2InputAvailable(i2ChanStrPtr pCh)
{
int count;
// Ensure channel structure seems real
if ( !i2Validate ( pCh ) ) return -1;
// initialize some accelerators and private copies
read_lock_irqsave(&pCh->Ibuf_spinlock, flags);
count = pCh->Ibuf_stuff - pCh->Ibuf_strip;
read_unlock_irqrestore(&pCh->Ibuf_spinlock, flags);
// Adjust for buffer wrap
if (count < 0)
{
count += IBUF_SIZE;
}
return count;
}
#endif
//******************************************************************************
// Function: i2Output(pCh, pSource, count)
// Parameters: Pointer to channel structure
// Pointer to source data
// Number of bytes to send
// Returns: Number of bytes sent, or -1 for error
//
// Description:
// Queues the data at pSource to be sent as data packets to the board. If there
// is a collosal blunder, (invalid structure pointers or the like), returns -1.
// Otherwise, returns the number of bytes written. What if there is not enough
// room for all the data? If pCh->channelOptions & CO_NBLOCK_WRITE is set, then
// we transfer as many characters as we can now, then return. If this bit is
// clear (default), routine will spin along until all the data is buffered.
// Should this occur, the 1-ms delay routine is called while waiting to avoid
// applications that one cannot break out of.
//******************************************************************************
static int
i2Output(i2ChanStrPtr pCh, const char *pSource, int count)
{
i2eBordStrPtr pB;
unsigned char *pInsert;
int amountToMove;
int countOriginal = count;
unsigned short channel;
unsigned short stuffIndex;
unsigned long flags;
int bailout = 10;
ip2trace (CHANN, ITRC_OUTPUT, ITRC_ENTER, 2, count, 0 );
// Ensure channel structure seems real
if ( !i2Validate ( pCh ) )
return -1;
// initialize some accelerators and private copies
pB = pCh->pMyBord;
channel = pCh->infl.hd.i2sChannel;
// If the board has gone fatal, return bad, and also hit the trap routine if
// it exists.
if (pB->i2eFatal) {
if (pB->i2eFatalTrap) {
(*(pB)->i2eFatalTrap)(pB);
}
return -1;
}
// Proceed as though we would do everything
while ( count > 0 ) {
// How much room in output buffer is there?
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;
}
// Subtract off the headers size and see how much room there is for real
// data. If this is negative, we will discover later.
amountToMove -= sizeof (i2DataHeader);
// Don't move more (now) than can go in a single packet
if ( amountToMove > (int)(MAX_OBUF_BLOCK - sizeof(i2DataHeader)) ) {
amountToMove = MAX_OBUF_BLOCK - sizeof(i2DataHeader);
}
// Don't move more than the count we were given
if (amountToMove > count) {
amountToMove = count;
}
// Now we know how much we must move: NB because the ring buffers have
// an overflow area at the end, we needn't worry about wrapping in the
// middle of a packet.
// Small WINDOW here with no LOCK but I can't call Flush with LOCK
// We would be flushing (or ending flush) anyway
ip2trace (CHANN, ITRC_OUTPUT, 10, 1, amountToMove );
if ( !(pCh->flush_flags && i2RetryFlushOutput(pCh) )
&& amountToMove > 0 )
{
write_lock_irqsave(&pCh->Obuf_spinlock, flags);
stuffIndex = pCh->Obuf_stuff;
// Had room to move some data: don't know whether the block size,
// buffer space, or what was the limiting factor...
pInsert = &(pCh->Obuf[stuffIndex]);
// Set up the header
CHANNEL_OF(pInsert) = channel;
PTYPE_OF(pInsert) = PTYPE_DATA;
TAG_OF(pInsert) = 0;
ID_OF(pInsert) = ID_ORDINARY_DATA;
DATA_COUNT_OF(pInsert) = amountToMove;
// Move the data
memcpy( (char*)(DATA_OF(pInsert)), pSource, amountToMove );
// Adjust pointers and indices
pSource += amountToMove;
pCh->Obuf_char_count += amountToMove;
stuffIndex += amountToMove + sizeof(i2DataHeader);
count -= amountToMove;
if (stuffIndex >= OBUF_SIZE) {
stuffIndex = 0;
}
pCh->Obuf_stuff = stuffIndex;
write_unlock_irqrestore(&pCh->Obuf_spinlock, flags);
ip2trace (CHANN, ITRC_OUTPUT, 13, 1, stuffIndex );
} else {
// Cannot move data
// becuz we need to stuff a flush
// or amount to move is <= 0
ip2trace(CHANN, ITRC_OUTPUT, 14, 3,
amountToMove, pB->i2eFifoRemains,
pB->i2eWaitingForEmptyFifo );
// Put this channel back on queue
// this ultimatly gets more data or wakes write output
i2QueueNeeds(pB, pCh, NEED_INLINE);
if ( pB->i2eWaitingForEmptyFifo ) {
ip2trace (CHANN, ITRC_OUTPUT, 16, 0 );
// or schedule
if (!in_interrupt()) {
ip2trace (CHANN, ITRC_OUTPUT, 61, 0 );
schedule_timeout_interruptible(2);
if (signal_pending(current)) {
break;
}
continue;
} else {
ip2trace (CHANN, ITRC_OUTPUT, 62, 0 );
// let interrupt in = WAS restore_flags()
// We hold no lock nor is irq off anymore???
break;
}
break; // from while(count)
}
else if ( pB->i2eFifoRemains < 32 && !pB->i2eTxMailEmpty ( pB ) )
{
ip2trace (CHANN, ITRC_OUTPUT, 19, 2,
pB->i2eFifoRemains,
pB->i2eTxMailEmpty );
break; // from while(count)
} else if ( pCh->channelNeeds & NEED_CREDIT ) {
ip2trace (CHANN, ITRC_OUTPUT, 22, 0 );
break; // from while(count)
} else if ( --bailout) {
// Try to throw more things (maybe not us) in the fifo if we're
// not already waiting for it.
ip2trace (CHANN, ITRC_OUTPUT, 20, 0 );
serviceOutgoingFifo(pB);
//break; CONTINUE;
} else {
ip2trace (CHANN, ITRC_OUTPUT, 21, 3,
pB->i2eFifoRemains,
pB->i2eOutMailWaiting,
pB->i2eWaitingForEmptyFifo );
break; // from while(count)
}
}
} // End of while(count)
i2QueueNeeds(pB, pCh, NEED_INLINE);
// We drop through either when the count expires, or when there is some
// count left, but there was a non-blocking write.
if (countOriginal > count) {
ip2trace (CHANN, ITRC_OUTPUT, 17, 2, countOriginal, count );
serviceOutgoingFifo( pB );
}
ip2trace (CHANN, ITRC_OUTPUT, ITRC_RETURN, 2, countOriginal, count );
return countOriginal - count;
}
//******************************************************************************
// Function: i2FlushOutput(pCh)
// Parameters: Pointer to a channel structure
// Returns: Nothing
//
// Description:
// Sends bypass command to start flushing (waiting possibly forever until there
// is room), then sends inline command to stop flushing output, (again waiting
// possibly forever).
//******************************************************************************
static inline void
i2FlushOutput(i2ChanStrPtr pCh)
{
ip2trace (CHANN, ITRC_FLUSH, 1, 1, pCh->flush_flags );
if (pCh->flush_flags)
return;
if ( 1 != i2QueueCommands(PTYPE_BYPASS, pCh, 0, 1, CMD_STARTFL) ) {
pCh->flush_flags = STARTFL_FLAG; // Failed - flag for later
ip2trace (CHANN, ITRC_FLUSH, 2, 0 );
} else if ( 1 != i2QueueCommands(PTYPE_INLINE, pCh, 0, 1, CMD_STOPFL) ) {
pCh->flush_flags = STOPFL_FLAG; // Failed - flag for later
ip2trace (CHANN, ITRC_FLUSH, 3, 0 );
}
}
static int
i2RetryFlushOutput(i2ChanStrPtr pCh)
{
int old_flags = pCh->flush_flags;
ip2trace (CHANN, ITRC_FLUSH, 14, 1, old_flags );
pCh->flush_flags = 0; // Clear flag so we can avoid recursion
// and queue the commands
if ( old_flags & STARTFL_FLAG ) {
if ( 1 == i2QueueCommands(PTYPE_BYPASS, pCh, 0, 1, CMD_STARTFL) ) {
old_flags = STOPFL_FLAG; //Success - send stop flush
} else {
old_flags = STARTFL_FLAG; //Failure - Flag for retry later
}
ip2trace (CHANN, ITRC_FLUSH, 15, 1, old_flags );
}
if ( old_flags & STOPFL_FLAG ) {
if (1 == i2QueueCommands(PTYPE_INLINE, pCh, 0, 1, CMD_STOPFL)) {
old_flags = 0; // Success - clear flags
}
ip2trace (CHANN, ITRC_FLUSH, 16, 1, old_flags );
}
pCh->flush_flags = old_flags;
ip2trace (CHANN, ITRC_FLUSH, 17, 1, old_flags );
return old_flags;
}
//******************************************************************************
// Function: i2DrainOutput(pCh,timeout)
// Parameters: Pointer to a channel structure
// Maximum period to wait
// Returns: ?
//
// Description:
// Uses the bookmark request command to ask the board to send a bookmark back as
// soon as all the data is completely sent.
//******************************************************************************
static void
i2DrainWakeup(unsigned long d)
{
i2ChanStrPtr pCh = (i2ChanStrPtr)d;
ip2trace (CHANN, ITRC_DRAIN, 10, 1, pCh->BookmarkTimer.expires );
pCh->BookmarkTimer.expires = 0;
wake_up_interruptible( &pCh->pBookmarkWait );
}
static void
i2DrainOutput(i2ChanStrPtr pCh, int timeout)
{
wait_queue_t wait;
i2eBordStrPtr pB;
ip2trace (CHANN, ITRC_DRAIN, ITRC_ENTER, 1, pCh->BookmarkTimer.expires);
pB = pCh->pMyBord;
// If the board has gone fatal, return bad,
// and also hit the trap routine if it exists.
if (pB->i2eFatal) {
if (pB->i2eFatalTrap) {
(*(pB)->i2eFatalTrap)(pB);
}
return;
}
if ((timeout > 0) && (pCh->BookmarkTimer.expires == 0 )) {
// One per customer (channel)
setup_timer(&pCh->BookmarkTimer, i2DrainWakeup,
(unsigned long)pCh);
ip2trace (CHANN, ITRC_DRAIN, 1, 1, pCh->BookmarkTimer.expires );
mod_timer(&pCh->BookmarkTimer, jiffies + timeout);
}
i2QueueCommands( PTYPE_INLINE, pCh, -1, 1, CMD_BMARK_REQ );
init_waitqueue_entry(&wait, current);
add_wait_queue(&(pCh->pBookmarkWait), &wait);
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) );
tty_wakeup(tp);
}
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 (I2_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->tqueue_input);
#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 */
case STAT_STATUS:
pCh->channelStatus = *((debugStatPtr)pc);
pc += sizeof(debugStat);
break;
case STAT_TXCNT:
pCh->channelTcount = *((cntStatPtr)pc);
pc += sizeof(cntStat);
break;
case STAT_RXCNT:
pCh->channelRcount = *((cntStatPtr)pc);
pc += sizeof(cntStat);
break;
case STAT_BOXIDS:
pB->channelBtypes = *((bidStatPtr)pc);
pc += sizeof(bidStat);
set_baud_params(pB);
break;
case STAT_HWFAIL:
i2QueueCommands (PTYPE_INLINE, pCh, 0, 1, CMD_HW_TEST);
pCh->channelFail = *((failStatPtr)pc);
pc += sizeof(failStat);
break;
/* No explicit match? then
* Might be an error packet...
*/
default:
switch (uc & STAT_MOD_ERROR)
{
case STAT_ERROR:
if (uc & STAT_E_PARITY) {
pCh->dataSetIn |= I2_PAR;
pCh->icount.parity++;
}
if (uc & STAT_E_FRAMING){
pCh->dataSetIn |= I2_FRA;
pCh->icount.frame++;
}
if (uc & STAT_E_OVERRUN){
pCh->dataSetIn |= I2_OVR;
pCh->icount.overrun++;
}
break;
case STAT_MODEM:
// the answer to DSS_NOW request (not change)
pCh->dataSetIn = (pCh->dataSetIn
& ~(I2_RI | I2_CTS | I2_DCD | I2_DSR) )
| xlatDss[uc & 0xf];
wake_up_interruptible ( &pCh->dss_now_wait );
default:
break;
}
} /* End of switch on status type */
if (dss_change) {
#ifdef USE_IQ
schedule_work(&pCh->tqueue_status);
#else
do_status(&pCh->tqueue_status);
#endif
}
}
else /* Or else, channel is invalid */
{
// Even though the channel is invalid, we must test the
// status to see how much additional data it has (to be
// skipped)
switch (*pc++)
{
case STAT_FLOW:
pc += 4; /* Skip the data */
break;
default:
break;
}
}
} // End of while (there is still some status packet left)
break;
default: // Neither packet? should be impossible
ip2trace (ITRC_NO_PORT, ITRC_SFIFO, 5, 1,
PTYPE_OF(pB->i2eLeadoffWord) );
write_unlock_irqrestore(&pB->read_fifo_spinlock,
bflags);
break;
} // End of switch on type of packets
} /*while(board I2_HAS_INPUT)*/
ip2trace (ITRC_NO_PORT, ITRC_SFIFO, ITRC_RETURN, 0 );
// Send acknowledgement to the board even if there was no data!
pB->i2eOutMailWaiting |= MB_IN_STRIPPED;
return;
}
//******************************************************************************
// Function: i2Write2Fifo(pB,address,count)
// Parameters: Pointer to a board structure, source address, byte count
// Returns: bytes written
//
// Description:
// Writes count bytes to board io address(implied) from source
// Adjusts count, leaves reserve for next time around bypass cmds
//******************************************************************************
static int
i2Write2Fifo(i2eBordStrPtr pB, unsigned char *source, int count,int reserve)
{
int rc = 0;
unsigned long flags;
write_lock_irqsave(&pB->write_fifo_spinlock, flags);
if (!pB->i2eWaitingForEmptyFifo) {
if (pB->i2eFifoRemains > (count+reserve)) {
pB->i2eFifoRemains -= count;
iiWriteBuf(pB, source, count);
pB->i2eOutMailWaiting |= MB_OUT_STUFFED;
rc = count;
}
}
write_unlock_irqrestore(&pB->write_fifo_spinlock, flags);
return rc;
}
//******************************************************************************
// Function: i2StuffFifoBypass(pB)
// Parameters: Pointer to a board structure
// Returns: Nothing
//
// Description:
// Stuffs as many bypass commands into the fifo as possible. This is simpler
// than stuffing data or inline commands to fifo, since we do not have
// flow-control to deal with.
//******************************************************************************
static inline void
i2StuffFifoBypass(i2eBordStrPtr pB)
{
i2ChanStrPtr pCh;
unsigned char *pRemove;
unsigned short stripIndex;
unsigned short packetSize;
unsigned short paddedSize;
unsigned short notClogged = 1;
unsigned long flags;
int bailout = 1000;
// Continue processing so long as there are entries, or there is room in the
// fifo. Each entry represents a channel with something to do.
while ( --bailout && notClogged &&
(NULL != (pCh = i2DeQueueNeeds(pB,NEED_BYPASS))))
{
write_lock_irqsave(&pCh->Cbuf_spinlock, flags);
stripIndex = pCh->Cbuf_strip;
// as long as there are packets for this channel...
while (stripIndex != pCh->Cbuf_stuff) {
pRemove = &(pCh->Cbuf[stripIndex]);
packetSize = CMD_COUNT_OF(pRemove) + sizeof(i2CmdHeader);
paddedSize = roundup(packetSize, 2);
if (paddedSize > 0) {
if ( 0 == i2Write2Fifo(pB, pRemove, paddedSize,0)) {
notClogged = 0; /* fifo full */
i2QueueNeeds(pB, pCh, NEED_BYPASS); // Put back on queue
break; // Break from the channel
}
}
#ifdef DEBUG_FIFO
WriteDBGBuf("BYPS", pRemove, paddedSize);
#endif /* DEBUG_FIFO */
pB->debugBypassCount++;
pRemove += packetSize;
stripIndex += packetSize;
if (stripIndex >= CBUF_SIZE) {
stripIndex = 0;
pRemove = pCh->Cbuf;
}
}
// Done with this channel. Move to next, removing this one from
// the queue of channels if we cleaned it out (i.e., didn't get clogged.
pCh->Cbuf_strip = stripIndex;
write_unlock_irqrestore(&pCh->Cbuf_spinlock, flags);
} // Either clogged or finished all the work
#ifdef IP2DEBUG_TRACE
if ( !bailout ) {
ip2trace (ITRC_NO_PORT, ITRC_ERROR, 1, 0 );
}
#endif
}
//******************************************************************************
// Function: i2StuffFifoFlow(pB)
// Parameters: Pointer to a board structure
// Returns: Nothing
//
// Description:
// Stuffs as many flow control packets into the fifo as possible. This is easier
// even than doing normal bypass commands, because there is always at most one
// packet, already assembled, for each channel.
//******************************************************************************
static inline void
i2StuffFifoFlow(i2eBordStrPtr pB)
{
i2ChanStrPtr pCh;
unsigned short paddedSize = roundup(sizeof(flowIn), 2);
ip2trace (ITRC_NO_PORT, ITRC_SFLOW, ITRC_ENTER, 2,
pB->i2eFifoRemains, paddedSize );
// Continue processing so long as there are entries, or there is room in the
// fifo. Each entry represents a channel with something to do.
while ( (NULL != (pCh = i2DeQueueNeeds(pB,NEED_FLOW)))) {
pB->debugFlowCount++;
// NO Chan LOCK needed ???
if ( 0 == i2Write2Fifo(pB,(unsigned char *)&(pCh->infl),paddedSize,0)) {
break;
}
#ifdef DEBUG_FIFO
WriteDBGBuf("FLOW",(unsigned char *) &(pCh->infl), paddedSize);
#endif /* DEBUG_FIFO */
} // Either clogged or finished all the work
ip2trace (ITRC_NO_PORT, ITRC_SFLOW, ITRC_RETURN, 0 );
}
//******************************************************************************
// Function: i2StuffFifoInline(pB)
// Parameters: Pointer to a board structure
// Returns: Nothing
//
// Description:
// Stuffs as much data and inline commands into the fifo as possible. This is
// the most complex fifo-stuffing operation, since there if now the channel
// flow-control issue to deal with.
//******************************************************************************
static inline void
i2StuffFifoInline(i2eBordStrPtr pB)
{
i2ChanStrPtr pCh;
unsigned char *pRemove;
unsigned short stripIndex;
unsigned short packetSize;
unsigned short paddedSize;
unsigned short notClogged = 1;
unsigned short flowsize;
unsigned long flags;
int bailout = 1000;
int bailout2;
ip2trace (ITRC_NO_PORT, ITRC_SICMD, ITRC_ENTER, 3, pB->i2eFifoRemains,
pB->i2Dbuf_strip, pB->i2Dbuf_stuff );
// Continue processing so long as there are entries, or there is room in the
// fifo. Each entry represents a channel with something to do.
while ( --bailout && notClogged &&
(NULL != (pCh = i2DeQueueNeeds(pB,NEED_INLINE))) )
{
write_lock_irqsave(&pCh->Obuf_spinlock, flags);
stripIndex = pCh->Obuf_strip;
ip2trace (CHANN, ITRC_SICMD, 3, 2, stripIndex, pCh->Obuf_stuff );
// as long as there are packets for this channel...
bailout2 = 1000;
while ( --bailout2 && stripIndex != pCh->Obuf_stuff) {
pRemove = &(pCh->Obuf[stripIndex]);
// Must determine whether this be a data or command packet to
// calculate correctly the header size and the amount of
// flow-control credit this type of packet will use.
if (PTYPE_OF(pRemove) == PTYPE_DATA) {
flowsize = DATA_COUNT_OF(pRemove);
packetSize = flowsize + sizeof(i2DataHeader);
} else {
flowsize = CMD_COUNT_OF(pRemove);
packetSize = flowsize + sizeof(i2CmdHeader);
}
flowsize = CREDIT_USAGE(flowsize);
paddedSize = roundup(packetSize, 2);
ip2trace (CHANN, ITRC_SICMD, 4, 2, pB->i2eFifoRemains, paddedSize );
// If we don't have enough credits from the board to send the data,
// flag the channel that we are waiting for flow control credit, and
// break out. This will clean up this channel and remove us from the
// queue of hot things to do.
ip2trace (CHANN, ITRC_SICMD, 5, 2, pCh->outfl.room, flowsize );
if (pCh->outfl.room <= flowsize) {
// Do Not have the credits to send this packet.
i2QueueNeeds(pB, pCh, NEED_CREDIT);
notClogged = 0;
break; // So to do next channel
}
if ( (paddedSize > 0)
&& ( 0 == i2Write2Fifo(pB, pRemove, paddedSize, 128))) {
// Do Not have room in fifo to send this packet.
notClogged = 0;
i2QueueNeeds(pB, pCh, NEED_INLINE);
break; // Break from the channel
}
#ifdef DEBUG_FIFO
WriteDBGBuf("DATA", pRemove, paddedSize);
#endif /* DEBUG_FIFO */
pB->debugInlineCount++;
pCh->icount.tx += flowsize;
// Update current credits
pCh->outfl.room -= flowsize;
pCh->outfl.asof += flowsize;
if (PTYPE_OF(pRemove) == PTYPE_DATA) {
pCh->Obuf_char_count -= DATA_COUNT_OF(pRemove);
}
pRemove += packetSize;
stripIndex += packetSize;
ip2trace (CHANN, ITRC_SICMD, 6, 2, stripIndex, pCh->Obuf_strip);
if (stripIndex >= OBUF_SIZE) {
stripIndex = 0;
pRemove = pCh->Obuf;
ip2trace (CHANN, ITRC_SICMD, 7, 1, stripIndex );
}
} /* while */
if ( !bailout2 ) {
ip2trace (CHANN, ITRC_ERROR, 3, 0 );
}
// Done with this channel. Move to next, removing this one from the
// queue of channels if we cleaned it out (i.e., didn't get clogged.
pCh->Obuf_strip = stripIndex;
write_unlock_irqrestore(&pCh->Obuf_spinlock, flags);
if ( notClogged )
{
ip2trace (CHANN, ITRC_SICMD, 8, 0 );
if ( pCh->pTTY ) {
ip2_owake(pCh->pTTY);
}
}
} // Either clogged or finished all the work
if ( !bailout ) {
ip2trace (ITRC_NO_PORT, ITRC_ERROR, 4, 0 );
}
ip2trace (ITRC_NO_PORT, ITRC_SICMD, ITRC_RETURN, 1,pB->i2Dbuf_strip);
}
//******************************************************************************
// Function: serviceOutgoingFifo(pB)
// Parameters: Pointer to a board structure
// Returns: Nothing
//
// Description:
// Helper routine to put data in the outgoing fifo, if we aren't already waiting
// for something to be there. If the fifo has only room for a very little data,
// go head and hit the board with a mailbox hit immediately. Otherwise, it will
// have to happen later in the interrupt processing. Since this routine may be
// called both at interrupt and foreground time, we must turn off interrupts
// during the entire process.
//******************************************************************************
static void
serviceOutgoingFifo(i2eBordStrPtr pB)
{
// If we aren't currently waiting for the board to empty our fifo, service
// everything that is pending, in priority order (especially, Bypass before
// Inline).
if ( ! pB->i2eWaitingForEmptyFifo )
{
i2StuffFifoFlow(pB);
i2StuffFifoBypass(pB);
i2StuffFifoInline(pB);
iiSendPendingMail(pB);
}
}
//******************************************************************************
// Function: i2ServiceBoard(pB)
// Parameters: Pointer to a board structure
// Returns: Nothing
//
// Description:
// Normally this is called from interrupt level, but there is deliberately
// nothing in here specific to being called from interrupt level. All the
// hardware-specific, interrupt-specific things happen at the outer levels.
//
// For example, a timer interrupt could drive this routine for some sort of
// polled operation. The only requirement is that the programmer deal with any
// atomiticity/concurrency issues that result.
//
// This routine responds to the board's having sent mailbox information to the
// host (which would normally cause an interrupt). This routine reads the
// incoming mailbox. If there is no data in it, this board did not create the
// interrupt and/or has nothing to be done to it. (Except, if we have been
// waiting to write mailbox data to it, we may do so.
//
// Based on the value in the mailbox, we may take various actions.
//
// No checking here of pB validity: after all, it shouldn't have been called by
// the handler unless pB were on the list.
//******************************************************************************
static inline int
i2ServiceBoard ( i2eBordStrPtr pB )
{
unsigned inmail;
unsigned long flags;
/* This should be atomic because of the way we are called... */
if (NO_MAIL_HERE == ( inmail = pB->i2eStartMail ) ) {
inmail = iiGetMail(pB);
}
pB->i2eStartMail = NO_MAIL_HERE;
ip2trace (ITRC_NO_PORT, ITRC_INTR, 2, 1, inmail );
if (inmail != NO_MAIL_HERE) {
// If the board has gone fatal, nothing to do but hit a bit that will
// alert foreground tasks to protest!
if ( inmail & MB_FATAL_ERROR ) {
pB->i2eFatal = 1;
goto exit_i2ServiceBoard;
}
/* Assuming no fatal condition, we proceed to do work */
if ( inmail & MB_IN_STUFFED ) {
pB->i2eFifoInInts++;
i2StripFifo(pB); /* There might be incoming packets */
}
if (inmail & MB_OUT_STRIPPED) {
pB->i2eFifoOutInts++;
write_lock_irqsave(&pB->write_fifo_spinlock, flags);
pB->i2eFifoRemains = pB->i2eFifoSize;
pB->i2eWaitingForEmptyFifo = 0;
write_unlock_irqrestore(&pB->write_fifo_spinlock,
flags);
ip2trace (ITRC_NO_PORT, ITRC_INTR, 30, 1, pB->i2eFifoRemains );
}
serviceOutgoingFifo(pB);
}
ip2trace (ITRC_NO_PORT, ITRC_INTR, 8, 0 );
exit_i2ServiceBoard:
return 0;
}