epca.c

来自「linux 内核源代码」· C语言 代码 · 共 2,328 行 · 第 1/5 页

			ch->m_dcd = 0x80;
			ch->m_dsr = 0x20;
			ch->m_cts = 0x10;
			ch->m_ri  = 0x40;
			ch->m_dtr = 0x01;
			break;

		case PCXE:
		case PCXEVE:
		case PCXI:
		case PC64XE:
			ch->m_rts = 0x02;
			ch->m_dcd = 0x08;
			ch->m_dsr = 0x10;
			ch->m_cts = 0x20;
			ch->m_ri  = 0x40;
			ch->m_dtr = 0x80;
			break;
		}

		if (boards[crd].altpin) {
			ch->dsr = ch->m_dcd;
			ch->dcd = ch->m_dsr;
			ch->digiext.digi_flags |= DIGI_ALTPIN;
		} else {
			ch->dcd = ch->m_dcd;
			ch->dsr = ch->m_dsr;
		}

		ch->boardnum   = crd;
		ch->channelnum = i;
		ch->magic      = EPCA_MAGIC;
		ch->tty        = NULL;

		if (shrinkmem) {
			fepcmd(ch, SETBUFFER, 32, 0, 0, 0);
			shrinkmem = 0;
		}

		tseg = readw(&bc->tseg);
		rseg = readw(&bc->rseg);

		switch (bd->type) {
		case PCIXEM:
		case PCIXRJ:
		case PCIXR:
			/* Cover all the 2MEG cards */
			ch->txptr = memaddr + ((tseg << 4) & 0x1fffff);
			ch->rxptr = memaddr + ((rseg << 4) & 0x1fffff);
			ch->txwin = FEPWIN | (tseg >> 11);
			ch->rxwin = FEPWIN | (rseg >> 11);
			break;

		case PCXEM:
		case EISAXEM:
			/* Cover all the 32K windowed cards */
			/* Mask equal to window size - 1 */
			ch->txptr = memaddr + ((tseg << 4) & 0x7fff);
			ch->rxptr = memaddr + ((rseg << 4) & 0x7fff);
			ch->txwin = FEPWIN | (tseg >> 11);
			ch->rxwin = FEPWIN | (rseg >> 11);
			break;

		case PCXEVE:
		case PCXE:
			ch->txptr = memaddr + (((tseg - bd->memory_seg) << 4) & 0x1fff);
			ch->txwin = FEPWIN | ((tseg - bd->memory_seg) >> 9);
			ch->rxptr = memaddr + (((rseg - bd->memory_seg) << 4) & 0x1fff);
			ch->rxwin = FEPWIN | ((rseg - bd->memory_seg) >>9 );
			break;

		case PCXI:
		case PC64XE:
			ch->txptr = memaddr + ((tseg - bd->memory_seg) << 4);
			ch->rxptr = memaddr + ((rseg - bd->memory_seg) << 4);
			ch->txwin = ch->rxwin = 0;
			break;
		}

		ch->txbufhead = 0;
		ch->txbufsize = readw(&bc->tmax) + 1;

		ch->rxbufhead = 0;
		ch->rxbufsize = readw(&bc->rmax) + 1;

		lowwater = ch->txbufsize >= 2000 ? 1024 : (ch->txbufsize / 2);

		/* Set transmitter low water mark */
		fepcmd(ch, STXLWATER, lowwater, 0, 10, 0);

		/* Set receiver low water mark */
		fepcmd(ch, SRXLWATER, (ch->rxbufsize / 4), 0, 10, 0);

		/* Set receiver high water mark */
		fepcmd(ch, SRXHWATER, (3 * ch->rxbufsize / 4), 0, 10, 0);

		writew(100, &bc->edelay);
		writeb(1, &bc->idata);

		ch->startc  = readb(&bc->startc);
		ch->stopc   = readb(&bc->stopc);
		ch->startca = readb(&bc->startca);
		ch->stopca  = readb(&bc->stopca);

		ch->fepcflag = 0;
		ch->fepiflag = 0;
		ch->fepoflag = 0;
		ch->fepstartc = 0;
		ch->fepstopc = 0;
		ch->fepstartca = 0;
		ch->fepstopca = 0;

		ch->close_delay = 50;
		ch->count = 0;
		ch->blocked_open = 0;
		init_waitqueue_head(&ch->open_wait);
		init_waitqueue_head(&ch->close_wait);

		spin_unlock_irqrestore(&epca_lock, flags);
	}

	printk(KERN_INFO
	        "Digi PC/Xx Driver V%s:  %s I/O = 0x%lx Mem = 0x%lx Ports = %d\n",
	        VERSION, board_desc[bd->type], (long)bd->port, (long)bd->membase, bd->numports);
	memwinoff(bd, 0);
}

static void epcapoll(unsigned long ignored)
{
	unsigned long flags;
	int crd;
	volatile unsigned int head, tail;
	struct channel *ch;
	struct board_info *bd;

	/*
	 * This routine is called upon every timer interrupt. Even though the
	 * Digi series cards are capable of generating interrupts this method
	 * of non-looping polling is more efficient. This routine checks for
	 * card generated events (Such as receive data, are transmit buffer
	 * empty) and acts on those events.
	 */
	for (crd = 0; crd < num_cards; crd++) {
		bd = &boards[crd];
		ch = card_ptr[crd];

		if ((bd->status == DISABLED) || digi_poller_inhibited)
			continue;

		/*
		 * assertmemoff is not needed here; indeed it is an empty
		 * subroutine. It is being kept because future boards may need
		 * this as well as some legacy boards.
		 */
		spin_lock_irqsave(&epca_lock, flags);

		assertmemoff(ch);

		globalwinon(ch);

		/*
		 * In this case head and tail actually refer to the event queue
		 * not the transmit or receive queue.
		 */
		head = readw(&ch->mailbox->ein);
		tail = readw(&ch->mailbox->eout);

		/* If head isn't equal to tail we have an event */
		if (head != tail)
			doevent(crd);
		memoff(ch);

		spin_unlock_irqrestore(&epca_lock, flags);
	} /* End for each card */
	mod_timer(&epca_timer, jiffies + (HZ / 25));
}

static void doevent(int crd)
{
	void __iomem *eventbuf;
	struct channel *ch, *chan0;
	static struct tty_struct *tty;
	struct board_info *bd;
	struct board_chan __iomem *bc;
	unsigned int tail, head;
	int event, channel;
	int mstat, lstat;

	/*
	 * This subroutine is called by epcapoll when an event is detected
	 * in the event queue. This routine responds to those events.
	 */
	bd = &boards[crd];

	chan0 = card_ptr[crd];
	epcaassert(chan0 <= &digi_channels[nbdevs - 1], "ch out of range");
	assertgwinon(chan0);
	while ((tail = readw(&chan0->mailbox->eout)) != (head = readw(&chan0->mailbox->ein))) { /* Begin while something in event queue */
		assertgwinon(chan0);
		eventbuf = bd->re_map_membase + tail + ISTART;
		/* Get the channel the event occurred on */
		channel = readb(eventbuf);
		/* Get the actual event code that occurred */
		event = readb(eventbuf + 1);
		/*
		 * The two assignments below get the current modem status
		 * (mstat) and the previous modem status (lstat). These are
		 * useful becuase an event could signal a change in modem
		 * signals itself.
		 */
		mstat = readb(eventbuf + 2);
		lstat = readb(eventbuf + 3);

		ch = chan0 + channel;
		if ((unsigned)channel >= bd->numports || !ch)  {
			if (channel >= bd->numports)
				ch = chan0;
			bc = ch->brdchan;
			goto next;
		}

		if ((bc = ch->brdchan) == NULL)
			goto next;

		if (event & DATA_IND)  { /* Begin DATA_IND */
			receive_data(ch);
			assertgwinon(ch);
		} /* End DATA_IND */
		/* else *//* Fix for DCD transition missed bug */
		if (event & MODEMCHG_IND) {
			/* A modem signal change has been indicated */
			ch->imodem = mstat;
			if (ch->asyncflags & ASYNC_CHECK_CD) {
				if (mstat & ch->dcd)  /* We are now receiving dcd */
					wake_up_interruptible(&ch->open_wait);
				else
					pc_sched_event(ch, EPCA_EVENT_HANGUP); /* No dcd; hangup */
			}
		}
		tty = ch->tty;
		if (tty) {
			if (event & BREAK_IND) {
				/* A break has been indicated */
				tty_insert_flip_char(tty, 0, TTY_BREAK);
				tty_schedule_flip(tty);
			} else if (event & LOWTX_IND)  {
				if (ch->statusflags & LOWWAIT) {
					ch->statusflags &= ~LOWWAIT;
					tty_wakeup(tty);
				}
			} else if (event & EMPTYTX_IND) {
				/* This event is generated by setup_empty_event */
				ch->statusflags &= ~TXBUSY;
				if (ch->statusflags & EMPTYWAIT) {
					ch->statusflags &= ~EMPTYWAIT;
					tty_wakeup(tty);
				}
			}
		}
	next:
		globalwinon(ch);
		BUG_ON(!bc);
		writew(1, &bc->idata);
		writew((tail + 4) & (IMAX - ISTART - 4), &chan0->mailbox->eout);
		globalwinon(chan0);
	} /* End while something in event queue */
}

static void fepcmd(struct channel *ch, int cmd, int word_or_byte,
                   int byte2, int ncmds, int bytecmd)
{
	unchar __iomem *memaddr;
	unsigned int head, cmdTail, cmdStart, cmdMax;
	long count;
	int n;

	/* This is the routine in which commands may be passed to the card. */

	if (ch->board->status == DISABLED)
		return;
	assertgwinon(ch);
	/* Remember head (As well as max) is just an offset not a base addr */
	head = readw(&ch->mailbox->cin);
	/* cmdStart is a base address */
	cmdStart = readw(&ch->mailbox->cstart);
	/*
	 * We do the addition below because we do not want a max pointer
	 * relative to cmdStart. We want a max pointer that points at the
	 * physical end of the command queue.
	 */
	cmdMax = (cmdStart + 4 + readw(&ch->mailbox->cmax));
	memaddr = ch->board->re_map_membase;

	if (head >= (cmdMax - cmdStart) || (head & 03))  {
		printk(KERN_ERR "line %d: Out of range, cmd = %x, head = %x\n", __LINE__,  cmd, head);
		printk(KERN_ERR "line %d: Out of range, cmdMax = %x, cmdStart = %x\n", __LINE__,  cmdMax, cmdStart);
		return;
	}
	if (bytecmd)  {
		writeb(cmd, memaddr + head + cmdStart + 0);
		writeb(ch->channelnum,  memaddr + head + cmdStart + 1);
		/* Below word_or_byte is bits to set */
		writeb(word_or_byte,  memaddr + head + cmdStart + 2);
		/* Below byte2 is bits to reset */
		writeb(byte2, memaddr + head + cmdStart + 3);
	}  else {
		writeb(cmd, memaddr + head + cmdStart + 0);
		writeb(ch->channelnum,  memaddr + head + cmdStart + 1);
		writeb(word_or_byte,  memaddr + head + cmdStart + 2);
	}
	head = (head + 4) & (cmdMax - cmdStart - 4);
	writew(head, &ch->mailbox->cin);
	count = FEPTIMEOUT;

	for (;;) {
		count--;
		if (count == 0)  {
			printk(KERN_ERR "<Error> - Fep not responding in fepcmd()\n");
			return;
		}
		head = readw(&ch->mailbox->cin);
		cmdTail = readw(&ch->mailbox->cout);
		n = (head - cmdTail) & (cmdMax - cmdStart - 4);
		/*
		 * Basically this will break when the FEP acknowledges the
		 * command by incrementing cmdTail (Making it equal to head).
		 */
		if (n <= ncmds * (sizeof(short) * 4))
			break;
	}
}

/*
 * Digi products use fields in their channels structures that are very similar
 * to the c_cflag and c_iflag fields typically found in UNIX termios
 * structures. The below three routines allow mappings between these hardware
 * "flags" and their respective Linux flags.
 */
static unsigned termios2digi_h(struct channel *ch, unsigned cflag)
{
	unsigned res = 0;

	if (cflag & CRTSCTS) {
		ch->digiext.digi_flags |= (RTSPACE | CTSPACE);
		res |= ((ch->m_cts) | (ch->m_rts));
	}

	if (ch->digiext.digi_flags & RTSPACE)
		res |= ch->m_rts;

	if (ch->digiext.digi_flags & DTRPACE)
		res |= ch->m_dtr;

	if (ch->digiext.digi_flags & CTSPACE)
		res |= ch->m_cts;

	if (ch->digiext.digi_flags & DSRPACE)
		res |= ch->dsr;

	if (ch->digiext.digi_flags & DCDPACE)
		res |= ch->dcd;

	if (res & (ch->m_rts))
		ch->digiext.digi_flags |= RTSPACE;

	if (res & (ch->m_cts))
		ch->digiext.digi_flags |= CTSPACE;

	return res;
}

static unsigned termios2digi_i(struct channel *ch, unsigned iflag)
{
	unsigned res = iflag & (IGNBRK | BRKINT | IGNPAR | PARMRK |
	                        INPCK | ISTRIP|IXON|IXANY|IXOFF);
	if (ch->digiext.digi_flags & DIGI_AIXON)
		res |= IAIXON;
	return res;
}

static unsigned termios2digi_c(struct channel *ch, unsigned cflag)
{
	unsigned res = 0;
	if (cflag & CBAUDEX) {
		ch->digiext.digi_flags |= DIGI_FAST;
		/*
		 * HUPCL bit is used by FEP to indicate fast baud table is to
		 * be used.
		 */
		res |= FEP_HUPCL;
	} else
		ch->digiext.digi_flags &= ~DIGI_FAST;
	/*
	 * CBAUD has bit position 0x1000 set these days to indicate Linux
	 * baud rate remap. Digi hardware can't handle the bit assignment.
	 * (We use a different bit assignment for high speed.). Clear this
	 * bit out.
	 */
	res |= cflag & ((CBAUD ^ CBAUDEX) | PARODD | PARENB | CSTOPB | CSIZE);
	/*
	 * This gets a little confusing. The Digi cards have their own
	 * representation of c_cflags controling baud rate. For the most part
	 * this is identical to the Linux implementation. However; Digi
	 * supports one rate (76800) that Linux doesn't. This means that the
	 * c_cflag entry that would normally mean 76800 for Digi actually means
	 * 115200 under Linux. Without the below mapping, a stty 115200 would
	 * only drive the board at 76800. Since the rate 230400 is also found
	 * after 76800, the same problem afflicts us when we choose a rate of
	 * 230400. Without the below modificiation stty 230400 would actually
	 * give us 115200.
	 *
	 * There are two additional differences. The Linux value for CLOCAL
	 * (0x800; 0004000) has no meaning to the Digi hardware. Also in later
	 * releases of Linux; the CBAUD define has CBAUDEX (0x1000; 0010000)
	 * ored into it (CBAUD = 0x100f as opposed to 0xf). CBAUDEX should be
	 * checked for a screened out prior to termios2digi_c returning. Since
	 * CLOCAL isn't used by the board this can be ignored as long as the
	 * returned value is used only by Digi hardware.
	 */
	if (cflag & CBAUDEX) {
		/*
		 * The below code is trying to guarantee that only baud rates
		 * 115200 and 230400 are remapped. We use exclusive or because
		 * the various baud rates share common bit positions and
		 * therefore can't be tested for easily.
		 */
		if ((!((cflag & 0x7) ^ (B115200 & ~CBAUDEX))) ||
		    (!((cflag & 0x7) ^ (B230400 & ~CBAUDEX))))
			res += 1;
	}
	return res;
}

/* Caller must hold the locks */
static void epcaparam(struct tty_struct *tty, struct channel *ch)
{
	unsigned int cmdHead;
	struct ktermios *ts;
	struct board_chan __iomem *bc;
	unsigned mval, hflow, cflag, iflag;

	bc = ch->brdchan;
	epcaassert(bc !=0, "bc out of range");

	assertgwinon(ch);
	ts = tty->termios;
	if ((ts->c_cflag & CBAUD) == 0)  { /* Begin CBAUD detected */
		cmdHead = readw(&bc->rin);
		writew(cmdHead, &bc->rout);
		cmdHead = readw(&bc->tin);
		/* Changing baud in mid-stream transmission can be wonderful */
		/*
		 * Flush current transmit buffer by setting cmdTail pointer
		 * (tout) to cmdHead pointer (tin). Hopefully the transmit
		 * buffer is empty.
		 */
		fepcmd(ch, STOUT, (unsigned) cmdHead, 0, 0, 0);
		mval = 0;
	} else { /* Begin CBAUD not detected */
		/*
		 * c_cflags have changed but that change had nothing to do with
		 * BAUD. Propagate the change to the card.
		 */
		cflag = termios2digi_c(ch, ts->c_cflag);
		if (cflag != ch->fepcflag)  {
			ch->fepcflag = cflag;